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ObjectiveParenchymal arterioles (PAs) regulate perfusion of the cerebral microcirculation, and impaired PA endothelium-dependent dilation occurs in dementia models mimicking chronic cerebral hypoperfusion (CCH). Epoxyeicosatrienoic acids (EETs) are vasodilators; their actions are potentiated by soluble epoxide hydrolase (sEH) inhibition. We hypothesized that chronic sEH inhibition with trifluoromethoxyphenyl-3 (1-propionylpiperidin-4-yl) urea (TPPU) would prevent cognitive dysfunction and improve PA dilation in a hypertensive CCH model.MethodsBilateral carotid artery stenosis (BCAS) was used to induce CCH in twenty-week-old male stroke-prone spontaneously hypertensive rats (SHSRP) that were treated with vehicle or TPPU for 8 weeks. Cognitive function was assessed by novel object recognition. PA dilation and structure were assessed by pressure myography, and mRNA expression in brain tissue was assessed by qRT-PCR.ResultsTPPU did not enhance resting cerebral perfusion, but prevented CCH-induced memory deficits. TPPU improved PA endothelium-dependent dilation but reduced the sensitivity of PAs to a nitric oxide donor. TPPU treatment had no effect on PA structure or biomechanical properties. TPPU treatment increased brain mRNA expression of brain derived neurotrophic factor, doublecortin, tumor necrosis factor-alpha, sEH, and superoxide dismutase 3, CONCLUSIONS: These data suggest that sEH inhibitors may be viable treatments for cognitive impairments associated with hypertension and CCH.

BackgroundNeurogenesis is significantly impaired in the brains of both human patients and experimental animal models of Alzheimer's disease (AD). Although deep brain stimulation promotes neurogenesis, it is an invasive technique that may damage neural circuitry along the path of the electrode. To circumvent this problem, we assessed whether intracranial electrical stimulation to the brain affects neurogenesis in a mouse model of Alzheimer's disease (5xFAD).Methods and resultsWe used Ki67, Nestin, and doublecortin (DCX) as markers and determined that neurogenesis in both the subventricular zone (SVZ) and hippocampus were significantly reduced in the brains of 4-month-old 5xFAD mice. Guided by a finite element method (FEM) computer simulation to approximately estimate current and electric field in the mouse brain, electrodes were positioned on the skull that were likely to deliver stimulation to the SVZ and hippocampus. After a 4-week program of 40-Hz intracranial alternating current stimulation (iACS), neurogenesis indicated by expression of Ki67, Nestin, and DCX in both the SVZ and hippocampus were significantly increased compared to 5xFAD mice who received sham stimulation. The magnitude of neurogenesis was close to the wild-type (WT) age-matched unmanipulated controls.ConclusionOur results suggest that iACS is a promising, less invasive technique capable of effectively stimulating the SVZ and hippocampus regions in the mouse brain. Importantly, iACS can significantly boost neurogenesis in the brain and offers a potential treatment for AD.

The bHLH transcription factor Olig2 is required for sequential cell fate determination of both motor neurons and oligodendrocytes and for progenitor proliferation in the central nervous system. However, the role of Olig2 in peripheral sensory neurogenesis remains unknown. We report that Olig2 is transiently expressed in the newly differentiated olfactory sensory neurons (OSNs) and is down-regulated in the mature OSNs in mice from early gestation to adulthood. Genetic fate mapping demonstrates that Olig2-expressing cells solely give rise to OSNs in the peripheral olfactory system. Olig2 depletion does not affect the proliferation of peripheral olfactory progenitors and the fate determination of OSNs, sustentacular cells, and the olfactory ensheathing cells. However, the terminal differentiation and maturation of OSNs are compromised in either Olig2 single or Olig1/Olig2 double knockout mice, associated with significantly diminished expression of multiple OSN maturation and odorant signaling genes, including Omp, Gnal, Adcy3, and Olfr15. We further demonstrate that Olig2 binds to the E-box in the Omp promoter region to regulate its expression. Taken together, our results reveal a distinctly novel function of Olig2 in the periphery nervous system to regulate the terminal differentiation and maturation of olfactory sensory neurons.

We combined translating ribosome affinity purification (TRAP) with in utero electroporation (IUE), called iTRAP to identify the molecular profile of specific neuronal populations during neonatal development without the need for viral approaches and FACS sorting. We electroporated a plasmid encoding EGFP-tagged ribosomal protein L10a at embryonic day (E) 14-15 to target layer 2-4 cortical neurons of the somatosensory cortex. At three postnatal (P) ages-P0, P7, and P14-when morphogenesis occurs and synapses are forming, TRAP and molecular profiling was performed from electroporated regions. We found that ribosome bound (Ribo)-mRNAs from ∼7300 genes were significantly altered over time and included classical neuronal genes known to decrease (e.g., Tbr1, Dcx) or increase (e.g., Eno2, Camk2a, Syn1) as neurons mature. This approach led to the identification of specific developmental patterns for Ribo-mRNAs not previously reported to be developmentally regulated in neurons, providing rationale for future examination of their role in selective biological processes. These include upregulation of Lynx1, Nrn1, Cntnap1 over time; downregulation of St8sia2 and Draxin; and bidirectional changes to Fkbp1b. iTRAP is a versatile approach that allows researchers to easily assess the molecular profile of specific neuronal populations in selective brain regions under various conditions, including overexpression and knockdown of target genes, and in disease settings.

Docosahexaenoic acid (DHA) and neuroprotectin D1 (NPD1) are neuroprotective after experimental ischemic stroke. To explore underlying mechanisms, SD rats underwent 2 h of middle cerebral artery occlusion (MCAo) and treated with DHA (5 mg/kg, IV) or NPD1 (5 μg/per rat, ICV) and vehicles 1 h after. Neuro-behavioral assessments was conducted on days 1, 2, and 3, and on week 1, 2, 3, or 4. BrdU was injected on days 4, 5, and 6, immunohistochemistry was performed on week 2 or 4, MRI on day 7, and lipidomic analysis at 4 and 5 h after onset of stroke. DHA improved short- and long-term behavioral functions and reduced cortical, subcortical, and total infarct volumes (by 42, 47, and 31%, respectively) after 2 weeks and reduced tissue loss by 50% after 4 weeks. DHA increased the number of BrdU+/Ki-67+, BrdU+/DCX+, and BrdU+/NeuN+ cells in the cortex, subventricular zone, and dentate gyrus and potentiated NPD1 synthesis in the penumbra at 5 h after MCAo. NPD1 improved behavior, reduced lesion volumes, protected ischemic penumbra, increased NeuN, GFAP, SMI-71-positive cells and vessels, axonal regeneration in the penumbra, and attenuated blood-brain barrier (BBB) after MCAo. We conclude that docosanoid administration increases neurogenesis and angiogenesis, activates NPD1 synthesis in the penumbra, and diminishes BBB permeability, which correlates to long-term neurobehavioral recovery after experimental ischemic stroke.

Unilateral brain injury is known to disrupt the balance between the two cortices, as evidenced by an abnormally high interhemispheric inhibitory drive from motor cortex M1intact to M1lesioned transmitted transcallosally. Our previous work has shown that the deletion of homeobox gene Emx1 not only led to the agenesis of the corpus callosum (cc), but also to reduced hippocampal neurogenesis. The current study sought to determine whether lacking the cc affected the recovery of forelimb function and hippocampal plasticity following training of the affected limb in mice with unilateral traumatic brain injuries (TBI). One week after TBI, produced by a controlled cortical impact to impair the preferred limb, Emx1 wild type (WT) and knock out (KO) mice were subjected to the single-pellet reaching task with the affected limb for 4 weeks. Both TBI and Emx1 deletion had overall adverse effects on the successful rate of reaching. However, TBI significantly affected reaching performance only in the WT mice and not in the KO mice. Both TBI and Emx1 gene deletion also negatively affected hippocampal neurogenesis, demonstrated by a reduction in doublecortin (DCX)-expressing immature neurons, while limb training enhanced DCX expression. However, limb training increased DCX cells in KO mice only in the TBI-treated group, whereas it induced neurogenesis in both WT mice groups regardless of the treatment. Our finding also suggests that limb training enhances neuroplasticity after brain injury at functionally remote regions including the hippocampus, which may have implications for promoting overall recovery of function after TBI.

Background: Postoperative cognitive dysfunction (POCD) represents a post-surgical complication that features progressive cognitive impairment and memory loss, often occurring in elderly patients. This study aimed to investigate the potential biological mechanisms underlying POCD., Methods: Male C57BL/6 mice (2 and 17 months old) were randomly assigned to surgery or control groups. The surgery group underwent laparotomy under 1.5% isoflurane anesthesia, while controls received no intervention. Cognitive function was assessed 7-10 days post-surgery using open field, Y-maze, and novel object recognition tests. Hippocampal mRNA expression was analyzed using Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment. A competing endogenous RNA (ceRNA) network was constructed using microRNA (miRNA) target prediction databases (miRanda, miRTarbase, miRcode) and sequencing results. Key findings were validated by RT-qPCR and immunofluorescence. The Connectivity Map (CMap) database was queried to predict potential POCD treatments., Results: Aging significantly affected mice's spontaneous activity in the open field test (F1, 28 = 8.933, P < 0.01) and the proportion of time spent in the center area (F1, 28 = 5.387, P < 0.05). Surgery significantly reduced the rate of spontaneous alternations in the Y-maze (F1, 28 = 16.94, P < 0.001) and the recognition index in novel object recognition test (F1, 28 = 6.839, P < 0.05) in aging mice, but had no effect on young mice. Transcriptome analysis revealed that aging and surgery downregulated multiple neurogenesis-related genes in the hippocampus. Doublecortin (DCX) immunofluorescence staining confirmed reduced hippocampal neurogenesis in aging mice, which was further decreased after surgery. We identified several key lncRNAs and miRNAs implicated in neurogenesis regulation. Additionally, drugs were predicted as potential therapeutic candidates for POCD treatment., Conclusion: Both aging and surgery have complex effects on the hippocampal transcriptome in mice. The significant decrease in neurogenesis may be a potential reason for the increased susceptibility of aging mice to POCD. The identified key regulatory lncRNAs, miRNAs, and drugs provide potential therapeutic targets for POCD prevention and treatment., Competing Interests: Declarations. Ethics approval and consent to participate: All animal research used in this work were authorized by the Committee for the Protection and Use of Animals of Sun Yat-sen University (permission number: SYSU-IACUC-2023-000809) as well as the Experimental Animal Ethics Committee of Sun Yat-sen University. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Metabolic syndrome (MS) is the medical term for the combination of at least three of the following factors: obesity, hyperlipidemia, hyperglycemia, insulin resistance, and hypertension. The spontaneously hypertensive rat (SHR) is an accepted animal model for the study of human MS that reveals all the features of the syndrome when fed high-fat, high-carbohydrate diets. The intake of high-fat diets in rats has been shown to produce brain neuropathology. In humans, MS increases the risk of cognitive impairment, dementia, and Alzheimer's disease. Genistein (GEN) is a phytoestrogen found in soy that lacks feminizing and carcinogenic effects and was found to have neuroprotective and anti-inflammatory effects in many pathological conditions. Considering that multiple data support that natural phytoestrogens may be therapeutic options for CNS maladies, we aim to elucidate if these properties also apply to a rat model of MS. Thus, GEN effects on neuroinflammation, neurogenesis, and cognition were evaluated in SHR eating a fat/carbohydrate-enriched diet. To characterize the neuropathology and cognitive dysfunction of MS we fed SHR with a high-fat diet (4520 kcal/kg) along with a 20% sucrose solution to drink. MS rats displayed a significant increase in body weight, BMI and obesity indexes along with an increased in fasting glucose levels, glucose intolerance, high blood pressure, and high blood triglyceride levels. MS rats were injected with GEN during 2 weeks a dose of 10 mg/kg. We found that MS rats showed a decreased number of DCX+ neural progenitors in the dentate gyrus and treatment with GEN increased this parameter. Expression of GFAP was increased in the DG and CA1 areas of the hippocampus and treatment decreased astrogliosis in all of them. We measured the expression of IBA1+ microglia in the same regions and classified microglia according to their morphology: we found that MS rats presented an increased proportion of the hypertrophied phenotype and GEN produced a shift in microglial phenotypes toward a ramified type. Furthermore, colocalization of IBA1 with the proinflammatory marker TNFα showed increased proportion of proinflammatory microglia in MS and a reduction with GEN treatment. On the other hand, colocalization with the anti-inflammatory marker Arg1 showed that MS has decreased proportion of anti-inflammatory microglia and GEN treatment increased this parameter. Cognitive dysfunction was evaluated in rats with MS using a battery of behavioral tests that assessed hippocampus-dependent spatial and working memory, such as the novel object recognition test (NOR), the novel object location test (NOL), and the free-movement pattern Y-maze (FMP-YMAZE) and the d-YMAZE. In all of them, MS performed poorly and GEN was able to improve cognitive impairments. These results indicate that GEN was able to exert neuroprotective actions increasing neurogenesis and improving cognitive impairments while decreasing astrogliosis, microgliosis, and neuroinflammatory environment in MS rats. Together, these results open an interesting possibility for proposing this phytoestrogen as a neuroprotective therapy for MS., (© 2024 British Society for Neuroendocrinology.)

Increasing shreds of evidence suggest that neurogenic-to-gliogenic shift may be critical to the abnormal neurodevelopment observed in individuals with Down syndrome (DS). REST, the Repressor Element-1 Silencing Transcription factor, regulates the differentiation and development of neural cells. Downregulation of REST may lead to defects in post-differentiation neuronal morphology in the brain of the DS fetal. This study aims to elucidate the role of REST in DS-derived NPCs using bioinformatics analyses and laboratory validations. We identified and validated vital REST-targeted DEGs: CD44, TGFB1, FN1, ITGB1, and COL1A1. Interestingly, these genes are involved in neurogenesis and gliogenesis in DS-derived NPCs. Furthermore, we identified nuclear REST loss and the neuroblast marker, DCX, was downregulated in DS human trisomic induced pluripotent stem cells (hiPSCs)-derived NPCs, whereas the glioblast marker, NFIA, was upregulated. Our findings indicate that the loss of REST is critical in the neurogenic-to-gliogenic shift observed in DS-derived NPCs. REST and its target genes may collectively regulate the NPC phenotype., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Social isolation is a risk factor for cognitive impairment. Adolescents may be particularly vulnerable to these effects, because they are in a critical period of development marked by significant physical, hormonal, and social changes. However, it is unclear if the effects of social isolation on learning and memory are similar in both sexes or if they persist into adulthood after a period of recovery. We socially isolated male and female 129Sv/Ev mice throughout adolescence (postnatal days 29-56), provided a 2-week resocialization recovery period, and then tested spatial learning and cognitive flexibility in the active place avoidance task. After behavioral testing, mice were injected with 5'-bromo-2'-deoxyuridine (BrdU) so that lasting effects of social isolation on cell proliferation in the dentate gyrus could be examined. Tissue was also stained for doublecortin (DCX). We found that in males, isolation led to a modest impairment in the rate of initial spatial learning, whereas in females, initial learning was unaffected. However, when the location of the shock zone was switched during the conflict variant of the task, cognitive flexibility was impaired in females only. Similarly, social isolation reduced cell proliferation and the number of immature neurons in the ventral dentate gyrus only in females. Together, these findings indicate that social isolation during adolescence differentially impairs spatial processing in males and females, with effects that persist into adulthood., (© 2025 Hanif et al.; Published by Cold Spring Harbor Laboratory Press.)

Various dietary factors in human milk are important nutrients for the formation of the infant gut microbiota (GM). While promoting the growth of the GM, some human milk components that are difficult to absorb and utilize will be broken down by the GM, and converted into nutrients that the baby can use, such as breast milk oligosaccharides-the 'carbon source' for infant GM. This study reveals that nucleotides (NTs), significant non-protein nitrogen sources in human milk, can enhance the abundance of beneficial microbial genera such as g&#95;Bifidobacterium, g&#95;Bacteroides, and g&#95;Blautia in in vitro fecal fermentation fluids of infants at low doses (2 mg/mL). Conversely, high doses of NTs (20 mg/mL) increased the abundance of g&#95;Escherichia-Shigella. Furthermore, low-dose NTs fermentation broth significantly enhanced the expression of neurodevelopmental marker genes such as Tuj1, Sox2, Dcx, and NeuN in NE-4C neural stem cells, whereas a single NTs digestion broth did not exhibit significant activity. However, in vivo studies using neonatal rats as a model demonstrated that both low-dose NTs fermentation broth and NTs digestive juices promoted behavioral development in neonatal rats (PND 20) and neuron maturation in the prefrontal cortex and hippocampus. Non-targeted metabolomics results indicate that low-dose dietary NTs promote the production of certain neuroregulatory metabolites in infant fecal fermentation, such as uridine, L-tyrosine, L-glutamic acid, and succinic acid. These findings suggest that NTs may serve as an important "nitrogen source" during GM formation in early life and have a dose effect in driving the development of the microbiota-gut-brain axis in early life., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Exercise (Ex) and environmental enrichment (EE) as the nondrug solutions have positive effects on cognitive behaviors and also increase the ability to cope with anxiety, fear, and stress. In this research, we decided to investigate the simultaneous effect of Ex and EE on anxiety-like behaviors and hippocampal neurogenesis markers in healthy rats. A total of 40 male Wistar rats were divided into four treatment groups: control, EE, Ex, and EE + Ex. Animals in EE groups were housed in large cages (50 × 50 × 50 cm) equipped with toys and objects of different shapes for 3 weeks. Ex-animals were forced to run on a treadmill once a day for 3 consecutive weeks. Open field (OF) and elevated plus maze (EPM) tests were used to evaluate anxiety behaviors. The hippocampal expression of early neurogenesis markers, doublecortin, and sex determining region Y-box 2, were measured using real-time-PCR. Ex and EE animals separately did not show any significant performance in reducing anxiety levels, neither in EPM nor in OF compared with the control group. When animals were treated with EE and Ex simultaneously, they showed significantly reduced anxiety in both EPM and OF tests compared with the control as well as Ex and EE groups separately. Both treatments in combination were also more effective than individual groups in increasing the neurogenesis molecular markers within the hippocampus. This study proposes that Ex in combination with cognitive engagement is more efficient in alleviating anxiety responses and that can develop a nonpharmacological and multidomain policy that may prevent or delay psychophysiological symptoms., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Alzheimer's disease (AD) is linked to the accumulation of Aβ, increased tau hyperphosphorylation, persistent neuroinflammation, and a decline in neurotrophic factors, neurogenesis, and synaptic plasticity. Oxytocin (OT) has a significant impact on memory and learning. We examined the influence of intranasal (IN) OT on synaptic plasticity, neurogenesis, histone acetylation, and spatial and cognitive memories in rats., Methods: Aβ 25-35 (5 µg/2.5 µl) was administered bilaterally in the CA1 of male Wistar rats for four consecutive days. After seven days of recovery, OT (2 µg/µl, 10 µl in each nostril) was administered IN for seven consecutive days. Working, spatial, and cognitive memories, and gene expression of neurogenesis- and synaptic plasticity-involved factors were measured in the hippocampus. Histone acetylation (H3K9 and H4K8) was also measured using western blotting., Results: IN administration of OT significantly improved working and spatial memory impairment induced by Aβ and increased the factors involved in synaptic plasticity (MeCP2, REST, synaptophysin, and BDNF) and neurogenesis (Ki67 and DCX). We also found an enhancement in the levels of H3K9ac and H4K8ac following OT administration., Conclusion: These findings indicated that IN OT could improve hippocampus-related behaviors by increasing synaptic plasticity, stimulating neurogenesis, and chromatin plasticity., Competing Interests: Declaration of Competing Interest The authors have no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: Transcription factor EB (TFEB), a key regulator of autophagy and lysosomal biogenesis, has diverse roles in various physiological processes. Enhancing lysosomal function by TFEB activation has recently been implicated in restoring neural stem cell (NSC) function. Overexpression of TFEB can inhibit the cell cycle of newborn cortical NSCs. It has also been found that TFEB regulates the pluripotency transcriptional network in mouse embryonic stem cells independent of autophagy and lysosomal biogenesis. This study aims to explore the effects of TFEB activation on neurogenesis in vivo through transgenic mice., Methods: We developed a glial fibrillary acidic protein (GFAP)-driven TFEB overexpression mouse model (TFEB GoE) by crossing the floxed TFEB overexpression mice and hGFAP-Cre mice. We performed immunohistochemical and fluorescence staining on brain tissue from newborn mice to assess neurogenesis changes, employing markers such as GFAP, Nestin, Ki67, doublecortin (DCX), Tbr1, and NeuN to trace different stages of neural development and cell proliferation., Results: TFEB GoE mice exhibited premature mortality, dying 10-20 days after birth. Immunohistochemical analysis revealed significant abnormalities, including disrupted hippocampal structure and cortical layering. Compared to control mice, TFEB GoE mice showed a marked increase in radial glial cells (RGCs) in the hippocampus and cortex, with Ki67 staining indicating these cells were predominantly in a quiescent state. This suggests that TFEB overexpression suppresses RGC proliferation. Additionally, abnormal distributions of migrating neurons and mature neurons were observed, highlighted by DCX, Tbr1, and NeuN staining, indicating a disruption in normal neurogenesis., Conclusion: This study, using transgenic animals in vivo, revealed that GFAP-driven TFEB overexpression leads to abnormal neural layering in the hippocampus and cortex by dysregulating neurogenesis. Our study is the first to discover the detrimental impact of TFEB overexpression on neurogenesis during embryonic development, which has important reference significance for future TFEB overexpression interventions in NSCs for treatment., Introduction: Transcription factor EB (TFEB), a key regulator of autophagy and lysosomal biogenesis, has diverse roles in various physiological processes. Enhancing lysosomal function by TFEB activation has recently been implicated in restoring neural stem cell (NSC) function. Overexpression of TFEB can inhibit the cell cycle of newborn cortical NSCs. It has also been found that TFEB regulates the pluripotency transcriptional network in mouse embryonic stem cells independent of autophagy and lysosomal biogenesis. This study aims to explore the effects of TFEB activation on neurogenesis in vivo through transgenic mice., Methods: We developed a glial fibrillary acidic protein (GFAP)-driven TFEB overexpression mouse model (TFEB GoE) by crossing the floxed TFEB overexpression mice and hGFAP-Cre mice. We performed immunohistochemical and fluorescence staining on brain tissue from newborn mice to assess neurogenesis changes, employing markers such as GFAP, Nestin, Ki67, doublecortin (DCX), Tbr1, and NeuN to trace different stages of neural development and cell proliferation., Results: TFEB GoE mice exhibited premature mortality, dying 10-20 days after birth. Immunohistochemical analysis revealed significant abnormalities, including disrupted hippocampal structure and cortical layering. Compared to control mice, TFEB GoE mice showed a marked increase in radial glial cells (RGCs) in the hippocampus and cortex, with Ki67 staining indicating these cells were predominantly in a quiescent state. This suggests that TFEB overexpression suppresses RGC proliferation. Additionally, abnormal distributions of migrating neurons and mature neurons were observed, highlighted by DCX, Tbr1, and NeuN staining, indicating a disruption in normal neurogenesis., Conclusion: This study, using transgenic animals in vivo, revealed that GFAP-driven TFEB overexpression leads to abnormal neural layering in the hippocampus and cortex by dysregulating neurogenesis. Our study is the first to discover the detrimental impact of TFEB overexpression on neurogenesis during embryonic development, which has important reference significance for future TFEB overexpression interventions in NSCs for treatment., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Doublecortin (DCX) is a microtubule-associated protein known to be a key regulator of neuronal migration and differentiation during brain development. However, the role of DCX, particularly in regulating the survival and growth of glioma cells, remains unclear. In this study, we utilized CRISPR/Cas9 technology to knock down DCX in the human glioma cell line (U251). DCX depletion suppressed cell proliferation and enhanced the pro-apoptotic effects of temozolomide (TMZ) and γ-radiation treatment. DCX knockdown led to the translocation of Bax to the mitochondria and mitochondria dysfunction. Furthermore, DCX deficiency-induced apoptosis took place along with the generation of reactive oxygen species (ROS), which is crucial in triggering mitochondrial membrane depolarization, the release of cytochrome c (Cyt-c), and caspase activation. Importantly, the transcriptional inhibition of DCX downregulated Rho-A, Net-1, and activated p38-MAPK cue, critical for cell survival and proliferation. Subsequent treatment with TMZ and γ-radiation further increased p38-MAPK activity through the decreased expression of Rho-A/Net-1, resulting in a significant reduction in glioma cell migration and invasion. Additionally, intracranial xenograft tumors of DCX-modified U251 cells in nude mice demonstrated inhibited tumor growth. Tumor sections treated with TMZ and γ-radiation exhibited a higher number of TUNEL-positive cells compared to the control group, indicating increased apoptosis. Our finding suggests that DCX depletion reduces glioma cell proliferation and promotes mitochondria-dependent apoptosis by enhancing the chemo and radiotherapy response. Targeting DCX represents a potential therapeutic target for glioma treatment., Competing Interests: Declarations. Ethics approval and consent to participate: This study did not include human participants, data, or tissue. All animal experiments were compliant with the Xuzhou Medical University Ethics Committee. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Introduction: Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by deficits in social interaction and communication, along with restricted and repetitive behaviors. Both genetic and environmental factors contribute to ASD, with prenatal exposure to valproic acid (VPA) and nicotine being linked to increased risk. Impaired adult hippocampal neurogenesis, particularly in the ventral region, is thought to play a role in the social deficits observed in ASD., Methods: In this study, we investigated social behavior and adult hippocampal neurogenesis in C57BL/6J mice prenatally exposed to VPA or nicotine, as well as in genetically modified ASD models, including IQSEC2 knockout (KO) and NLGN3-R451C knock-in (KI) mice. Sociability and social novelty preference were evaluated using a three-chamber social interaction test. Adult hippocampal neurogenesis was assessed by BrdU and DCX immunofluorescence to identify newborn and immature neurons., Results: VPA-exposed mice displayed significant deficits in social interaction, while nicotine-exposed mice exhibited mild impairment in social novelty preference. Both IQSEC2 KO and NLGN3-R451C KI mice demonstrated reduced adult neurogenesis, particularly in the ventral hippocampus, a region associated with social behavior and emotion. Across all ASD mouse models, a significant reduction in BrdU+/NeuN+ cells in the ventral hippocampus was observed, while dorsal hippocampal neurogenesis remained relatively unaffected. Similar reductions in DCX-positive cells were identified in VPA, nicotine, and NLGN3-R451C KI mice, indicating impaired proliferation or differentiation of neuronal progenitors., Discussion: These findings suggest that impaired adult neurogenesis in the ventral hippocampus is a common hallmark across ASD mouse models and may underlie social behavior deficits. This study provides insight into region-specific neurogenic alterations linked to ASD pathophysiology and highlights potential targets for therapeutic interventions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Sun, Ohashi, Mori, Mizuno, Zang, Guo, Kouyama-Suzuki, Shirai and Tabuchi.)

Schizophrenia is a kind of neurodevelopmental mental disorder in which patients begin to experience changes early in their development, typically manifesting around or after puberty and has a fluctuating course. Environmental disturbances during adolescence may be a risk factor for schizophrenia-like deficits. As a better treatment option, preventive intervention prior to schizophrenia may be more beneficial than direct treatment. More effective stress-relieving interventions during the critical puberty period may prevent schizophrenia-like neuronal changes and the transition to schizophrenia in adulthood. Pyridoxine deficiency alters the function of NMDA (n-methyl-D-aspartic acid) receptors and plays a key role in learning and memory. In this study, we prepared a progeny model of schizophrenia by exposing pregnant rats to methoxymethanol acetate (MAM) on gestational day 17. The offspring rats were injected intraperitoneally with pyridoxine daily from birth to prepuberty PND12-PND21), and behavioral changes in the offspring rats were observed in adulthood. Cannabinoid receptor interacting protein 1 (CNRIP1) and cannabinoid receptor-1 (CB1R), which regulate memory, cognitive and motor activity, were detected in the prefrontal cortex (PFC) and hippocampus of the offspring rats, and the cell proliferation in the hippocampal dentate gyrus (DG) was also observed. The results showed that the MAM rats spent less time the open arm in the elevated plus maze test, decreased discrimination coefficient in novel object recognition test, and decreased prepulse inhibition, while the MAM rats supplemented with pyridoxine in prepuberty did not show any of the above abnormal behavioral changes in adulthood. By examining related proteins in the PFC and hippocampus, we found that only CB1R protein expression was downregulated in the PFC, whereas CNRIP1 expression was not only elevated in the hippocampus, but also significantly increased in pyridoxine- supplemented MAM rats. Meanwhile, pyridoxine supplementation alleviated the reduction of doublecortin (DCX)-positive cells and Ki67-positive cells in MAM rats. These results indicate that prepuberty pyridoxine supplementation has a positive effect on the prevention of cognitive deficits and sensorimotor gating impairment in MAM-induced schizophrenia-like rats, accompanied by changes in the CB1R and CNRIP1 expression in PFC and hippocampus, as well as the regeneration of neurons in the DG region., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Doublecortin (DCX) is a microtubule (MT)-associated protein in immature neurons. DCX is essential for early brain development, 1 and DCX mutations account for nearly a quarter of all cases of lissencephaly-spectrum brain malformations 2 , 3 that arise from a neuronal migration failure through the developing cortex. 4 By analyzing pathogenic DCX missense mutations in non-neuronal cells, we show that disruption of MT binding is central to DCX pathology. In human-induced pluripotent stem cell (hiPSC)-derived cortical i 3 Neurons, genome edited to express DCX-mEmerald from the endogenous locus, DCX-MT interactions polarize very early during neuron morphogenesis. DCX interacts with MTs through two conserved DCX domains 5 , 6 that bind between protofilaments and adjacent tubulin dimers, 7 a site that changes conformation during guanosine triphosphate (GTP) hydrolysis. 8 Consequently and consistent with our previous results, 5 DCX specifically binds straight growth cone MTs and is excluded from the GTP/guanosine diphosphate (GDP)-inorganic phosphate (Pi) cap recognized by end-binding proteins (EBs). Comparing MT-bound DCX fluorescence to mEmerald-tagged nanocage standards, we measure approximately one hundred DCX molecules per micrometer growth cone MT. DCX is required for i 3 Neuron growth cone advance in soft microenvironments that mimic the viscoelasticity of brain tissue, and using high-resolution traction force microscopy, we find that growth cones produce comparatively small and transient traction forces. Given our finding that DCX stabilizes MTs in the growth cone periphery by inhibiting MT depolymerization, we propose that DCX contributes to growth cone biomechanics and reinforces the growth cone cytoskeleton to counteract actomyosin-generated contractile forces in soft physiological environments in which weak and transient adhesion-mediated traction may be insufficient for productive growth cone advance., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Brain microvascular endothelial cells (BMECs), an important component of the neurovascular unit, can promote angiogenesis and synaptic formation in ischaemic mice after brain parenchyma transplantation. Since the therapeutic efficacy of cell-based therapies depends on the extent of transplanted cell residence in the target tissue and cell migration ability, the delivery route has become a hot research topic. In this study, we investigated the effects of carotid artery transplantation of BMECs on neuronal injury, neurorepair, and neurological dysfunction in rats after cerebral ischaemic attack. Purified passage 1 endothelial cells (P1-BMECs) were prepared from mouse brain tissue. Adult rats were subjected to transient middle cerebral artery occlusion (MCAO) for 30 min. Then, the rats were treated with 5 × 10 5 P1-BMECs through carotid artery infusion or tail vein injection. We observed that carotid artery transplantation of BMECs produced more potent neuroprotective effects than caudal injection in MCAO rats, including reducing infarct size and alleviating neurological deficits in behavioural tests. Carotid artery-transplanted BMECs displayed a wider distribution in the ischaemic rat brain. Immunostaining for endothelial progenitor cells and the mature endothelial cell markers CD34 and RECA-1 showed that carotid artery transplantation of BMECs significantly increased angiogenesis. Carotid artery transplantation of BMECs significantly increased the number of surviving neurons, decreased the cerebral infarction volume, and alleviated neurological deficits. In addition, we found that carotid artery transplantation of BMECs significantly enhanced ischaemia-induced hippocampal neurogenesis, as measured by doublecortin (DCX) and Ki67 double staining within 2 weeks after ischaemic injury. We conclude that carotid artery transplantation of BMECs can promote cerebral angiogenesis, neurogenesis, and neurological function recovery in adult rats after ischaemic stroke. Our results suggest that carotid injection of BMECs may be a promising new approach for treating acute brain injuries., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Shanghai Institute of Materia Medica, Chinese Academy of Sciences and Chinese Pharmacological Society.)

Neuronal injury, neurodegeneration, and neuroanatomical changes are key pathological features of various neurological disorders, including epilepsy, stroke, traumatic brain injury, Parkinson's disease, autism, and Alzheimer's disease. Accurate quantification of neurons and interneurons in different brain regions is critical for understanding the progression of neurodegenerative disorders in animal models. Traditional scoring methods are often superficial, biased, and unreliable for evaluating neuropathology. Stereology, a quantitative tool that uses 3-dimensional visualization of cells, provides a robust protocol for evaluating neuronal injury and neurodegeneration. This article presents a comprehensive and optimized stereology protocol for unbiased quantification of neuronal injury, neurodegeneration, and neurogenesis in rat and mouse models. This protocol involves precise counting of injured neurons, surviving neurons, and interneurons through immunohistochemical processing of brain sections for NeuN(+) principal neurons, parvalbumin (PV+) interneurons, doublecortin (DCX+) newborn neurons, and Fluoro-Jade B (FJB+)-stained injured cells. Predefined hippocampal and amygdala regions were identified and analyzed using a Visiopharm stereology software-driven compound microscope. Cell density and absolute cell numbers were determined using the optical fractionation method. Our stereology protocol accurately estimated 1.5 million total NeuN(+) principal neurons and 0.05 million PV(+) interneurons in the rat hippocampus, as well as 1.2 million total principal neurons and 0.025 million interneurons in the mouse hippocampus. FJB(+) counting provided a quantitative index of damaged neurons, and the stereology of DCX(+) neurons demonstrated the extent of neurogenesis. Overall, this stereology protocol enables precise, accurate, and unbiased counting of total neurons in any brain region. This offers a reliable quantitative tool for studying neuronal injury and protection in various models of acute brain injury, neurotoxicity, and chronic neurological disorders. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Stereological quantification of principal neurons, interneurons, and immature neurons in the hippocampus in rat brain sections Basic Protocol 2: Stereological quantification of principal neurons, interneurons, and immature neurons in the hippocampus in mouse brain sections Basic Protocol 3: Stereological quantification of injured or necrotized cells stained with Fluoro-Jade B in the hippocampus and amygdala in rats Basic Protocol 4: Stereological quantification of injured or necrotized cells stained with Fluoro-Jade B in the hippocampus and amygdala regions in mice Basic Protocol 5: Brain fixation and histology processing Basic Protocol 6: Immunochemistry of principal neurons, interneurons, and newborn neurons Basic Protocol 7: Fluoro-Jade B staining of injured neurons., (© 2024 Wiley Periodicals LLC.)

The neurogenic potential of the brain decreases during ageing, whereas the risk of neurodegenerative diseases and stroke rises. This creates a mismatch between the rate of neuron loss and the brain's capacity for replacement. Adult neurogenesis primarily occurs in the subgranular zone (SGZ) and the ventricular-subventricular zone (V-SVZ). Exercise enhances SGZ neurogenesis, and we previously showed that V-SVZ neurogenesis is induced by exercise via activation of the lactate receptor HCA 1 . Here, we investigated how high-intensity interval training (HIIT) and medium-intensity interval training (MIIT) affect neurogenesis in these niches. Wild-type (WT) and HCA 1 knockout (KO) mice were randomized to sedentary, HIIT or MIIT (n = 5-8 per group) for 3 weeks. In the SGZ, HIIT increased the density of doublecortin (DCX)-positive cells in WT mice by 85% (5.77±1.76 vs. 3.12±1.54 cells/100 µm, P = 0.013) and KO mice (67% increase; 7.91±2.92 vs. 4.73±1.63 cells/100 µm, P = 0.004). MIIT did not alter the density of DCX-positive cells in either genotype. HIIT increased the density of Ki-67-positive cells only in KO mice (P = 0.038), whereas no differences in nestin-positive cells were observed. In the V-SVZ, HIIT increased the density of DCX-positive cells in WT mice by 155% (117.79±39.72 vs. 46.25±19.96 cells/100 µm, P < 0.001) and MIIT increased the density of DCX-positive cells by 80% (83.26±39.48 vs. 46.25±19.96 cells/100µm, P = 0.027). No exercise-induced changes were observed in KO mice. Similar patterns were noted for Ki-67 positive and DCX/Ki-67 double-positive cells in the V-SVZ. These findings suggest that HIIT enhances neurogenesis more robustly than MIIT in both niches, with HCA 1 playing a crucial role in V-SVZ neurogenesis. KEY POINTS: The neurogenic potential of the brain decreases with age, whereas the risk of neurodegenerative diseases and stroke increases, highlighting a mismatch between neuronal loss and replacement capacity. Exercise enhances neurogenesis in both the subgranular zone and the ventricular-subventricular zone. High-intensity interval exercise is more effective than medium-intensity interval exercise at promoting neurogenesis in both the subgranular zone and the ventricular-subventricular zone of wild-type mice. The enhancement of neurogenesis in the ventricular-subventricular zone is dependent on the activation of the HCA 1 receptor, as evidenced by the ability of medium- and high-intensity interval exercise to induce neurogenesis in wild-type mice and the lack of this effect in HCA 1 knockout mice. By contrast, neurogenesis in the subgranular zone is independent on the activation of the HCA 1 receptor, highlighting that neurogenesis in the two major neurogenic niches are regulated differently., (© 2024 The Author(s). The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Lissencephaly is a rare brain malformation characterized by abnormal neuronal migration during cortical development. In this study, we performed a comprehensive genetic analysis using next-generation sequencing in 12 unsolved Japanese lissencephaly patients, in whom PAFAH1B1, DCX, TUBA1A, and ARX variants were excluded using the Sanger method. Exome sequencing (ES) was conducted on these 12 patients, identifying pathogenic variants in CEP85L, DYNC1H1, LAMC3, and DCX in four patients. Next, we performed genome sequencing (GS) on eight unsolved patients, and structural variants in PAFAH1B1, including an inversion and microdeletions involving several exons, were detected in three patients. Notably, these microdeletions in PAFAH1B1 could not to be detected by copy number variation (CNV) detection tools based on the depth of coverage methods using ES data. The density of repeat sequences, including Alu sequences or segmental duplications, which increase the susceptibility to structural variations, is very high in some lissencephaly spectrum genes (PAFAH1B1, TUBA1A, DYNC1H1). These missing CNVs were due to the limitations of detecting repeat sequences in ES-based CNV detection tools. Our study suggests that a combined approach integrating ES with GS can contribute to a higher diagnostic yield and a better understanding of the genetic landscape of the lissencephaly spectrum., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to The Japan Society of Human Genetics.)

Rationale: The literature indicates that nicotine exposure or its discontinuation impair adult hippocampal neurogenesis in rats, though the impact of exercise on this process remains unclear. We have previously shown that disturbances in the number of doublecortin (DCX, a marker of immature neurons)-positive (DCX + ) cells in the dentate gyrus (DG) of the hippocampus during nicotine deprivation may contribute to a depression-like state in rats., Objectives: This study aimed to investigate the effect of running on hippocampal neurogenesis, depression-like symptoms, and drug-seeking behaviour during nicotine deprivation., Methods: The rats were subjected to nicotine (0.03 mg/kg/inf) self-administration via an increasing schedule of reinforcement. After 21 sessions, the animals entered a 14-day abstinence phase during which they were housed in either standard home cages without wheels, cages equipped with running wheels, or cages with locked wheels., Results: Wheel running increased the number of K i -67 +  and DCX +  cells in the DG of both nicotine-deprived and nicotine-naive rats. Wheel-running exercise evoked an antidepressant effect on abstinence Day 14 but had no effect on nicotine-seeking behaviour on abstinence Day 15 compared to rats with locked-wheel access., Conclusions: In summary, long-term wheel running positively affected the number of immature neurons in the hippocampus, which corresponded with an antidepressant response in nicotine-weaned rats. One possible mechanism underlying the positive effect of running on the affective state during nicotine cessation may be the reduction in deficits in DCX +  cells in the hippocampus., Competing Interests: Declarations Ethics approval This research adhered to the principles outlined in the European Community Council Directive 2010/63/EU for animal experiments, and received approval from the II Local Ethics Committee at Maj Institute of Pharmacology, Polish Academy of Sciences (permission numbers: 1240/2015, 1273/2015, 186/2016, 161/2017, 353/2017, 354/2017). Conflict of interest The authors declare no conflict of interests., (© 2024. The Author(s).)

The hippocampus is one of the most vulnerable regions affected in disorders characterized by overt neuroinflammation such as neurodegenerative diseases. Pleiotrophin (PTN) is a neurotrophic factor that modulates acute neuroinflammation in different contexts. PTN is found highly upregulated in the brain in different chronic disorders characterized by neuroinflammation, suggesting an important role in the modulation of sustained neuroinflammation. To test this hypothesis, we studied the acute and long-term effects of a single lipopolysaccharide (LPS; 5 mg/kg) administration in Ptn +/+ and Ptn -/- mice, and in mice with Ptn-overexpression (Ptn-Tg). Endogenous PTN levels proportionally modulate LPS-induced increase in TNF-α plasma levels one hour after treatment. In the dentate gyrus (DG) of the hippocampus, a lower percentage of DCX+ cells were detected in saline-treated Ptn -/- mice compared to Ptn +/+ mice, suggesting a crucial role of PTN in the maintenance of hippocampal neuronal progenitors. The data show that PTN overexpression tends to potentiate acute microglial responses in the DG 16 hours after LPS treatment. Remarkably, a significant increase in the number of neuronal progenitors together with astrogliosis was detected 10 months after a single injection of LPS treatment in wild type mice. However, these LPS-induced long-term effects were prevented in Ptn -/- and Ptn-Tg mice, suggesting that PTN modulates LPS-induced long-term neurogenesis changes and astrocytic response in the hippocampus. The data presented here suggest that endogenous PTN levels are crucial in the regulation of acute LPS-induced systemic and hippocampal microglial responses in young mice. Furthermore, our findings provide evidence of the key role of PTN in the regulation of long-term LPS effects on astrocytic response and neurogenesis in the hippocampus., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Patients with lissencephaly typically present with severe psychomotor retardation and drug-resistant seizures. The aim of this study was to characterize the epileptic phenotype in a genotypically and radiologically well-defined patient cohort and to evaluate the response to antiseizure medication (ASM). Therefore, we retrospectively evaluated 47 patients of five genetic forms ( LIS1/PAFAH1B1 , DCX , DYNC1H1 , TUBA1A , TUBG1 ) using family questionnaires, standardized neuropediatric assessments, and patients' medical reports., Results: All but two patients were diagnosed with epilepsy. Median age at seizure onset was 6 months (range: 2.1-42.0), starting with epileptic spasms in 70%. Standard treatment protocols with hormonal therapy (ACTH or corticosteroids) and/or vigabatrin were the most effective approach for epileptic spasms, leading to seizure control in 47%. Seizures later in the disease course were most effectively treated with valproic acid and lamotrigine, followed by vigabatrin and phenobarbital, resulting in seizure freedom in 20%. Regarding psychomotor development, lissencephaly patients presenting without epileptic spasms were significantly more likely to reach various developmental milestones compared to patients with spasms., Conclusion: Classic lissencephaly is highly associated with drug-resistant epilepsy starting with epileptic spasms in most patients. The standard treatment protocols for infantile epileptic spasms syndrome lead to freedom from seizures in around half of the patients. Due to the association of epileptic spasms with an unfavorable course of psychomotor development, early and reliable diagnosis and treatment of spasms should be pursued. For epilepsies occurring later in childhood, ASM with valproic acid and lamotrigine, followed by vigabatrin and phenobarbital, appears to be most effective., Competing Interests: None declared., (Thieme. All rights reserved.)

Notch signaling, a classical signaling pathway of neurogenesis, is downregulated during the aging and age-related neurodegenerative diseases. Exercise has been proposed as an effective lifestyle intervention for delaying cognitive decline. However, it remains unclear whether exercise intervention could alleviate cognitive decline by modulating neurogenesis in naturally aging rats. In this study, 21-month-old natural aging rats were used to study brain aging. The natural aging rats underwent different forms of exercise training (aerobic exercise or strength training or comprehensive exercise with aerobic exercise and strength training) for 12 consecutive weeks. The cognitive function of natural aging rats was determined by Morris Water Maze. Notch signaling, autophagy-related proteins and hippocampal neurogenesis were examined by immunofluorescence, qRT-PCR and Western blot. Results showed that natural aging rats exhibited cognitive decline, accumulation of AD pathological proteins (APP and Aβ), and decreased neurogenesis (decreased DCX, Ki67 and GFAP), compared with the young control rats. Moreover, a significant decline in Notch signaling and autophagy was found in the hippocampus of natural aging rats. However, different forms of exercise upregulated Notch signaling and its downstream target genes, as well as autophagy-related proteins, including LC3, Beclin1, and p62. In summary, our data suggest that different forms of exercise can mitigate brain aging by upregulating Notch signaling and autophagy, thereby increasing hippocampal neurogenesis and improves spatial learning and memory abilities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Abnormal tryptophan metabolism is closely linked with neurological disorders. Research has shown that indoleamine 2,3-dioxygenase 1 (IDO-1), the first rate-limiting enzyme in tryptophan degradation, is upregulated in Parkinson's disease (PD). However, the precise role of IDO-1 in PD pathogenesis remains elusive. In this study, we administered 1-methyl-tryptophan (1-MT), an IDO-1 inhibitor, intraperitoneally at 15 mg/kg daily for 21 days to PD mice induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) at 30 mg/kg daily for 5 days. Our results show that IDO-1 inhibition improves behavioral performance, reduces dopaminergic neuron loss, and decreases serum quinolinic acid (QA) content and the aryl hydrocarbon receptor (AHR) expression in the striatum and colon. It also alleviates glial-associated neuroinflammation and mitigates colonic inflammation (decreasing iNOS, COX2) by suppressing the Toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway. Furthermore, IDO-1 inhibition promotes hippocampal neurogenesis (increasing doublecortin positive (DCX + ) cells and SOX2 + cells), which have recently been recognized as key pathological features and potential therapeutic targets in PD, likely through the activation of the BDNF/TrkB pathway. We further explored the gut-brain connection by depleting the gut microbiota in mice using antibiotics. Notably, the neuroprotective effects of IDO-1 inhibition were completely abolished in pseudo-germ-free mice (administrated an antibiotic mixture orally for 14 days prior to 1-MT treatment), highlighting the dependency of 1-MT's neuroprotective effects on the presence of gut microbiota. Finally, we found IDO-1 inhibition corrects the abnormal elevation of fecal short chain fatty acids (SCFAs). Collectively, these findings suggest that IDO-1 inhibition may represent a promising therapeutic approach for PD., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2025 Elsevier Inc. All rights reserved.)

Many microtubule (MT) functions are mediated by a diverse class of proteins (+TIPs) at growing MT plus ends that control intracellular MT interactions and dynamics and depend on end-binding proteins (EBs) [1]. Cryoelectron microscopy has recently identified the EB binding site as the interface of four tubulin dimers that undergoes a conformational change in response to β-tubulin GTP hydrolysis [2, 3]. Doublecortin (DCX), a MT-associated protein (MAP) required for neuronal migration during cortical development [4, 5], binds to the same site as EBs [6], and recent in vitro studies proposed DCX localization to growing MT ends independent of EBs [7]. Because this conflicts with observations in neurons [8, 9] and the molecular function of DCX is not well understood, we revisited intracellular DCX dynamics at low expression levels. Here, we report that DCX is not a +TIP in cells but, on the contrary, is excluded from the EB1 domain. In addition, we find that DCX-MT interactions are highly sensitive to MT geometry. In cells, DCX binding was greatly reduced at MT segments with high local curvature. Remarkably, this geometry-dependent binding to MTs was completely reversed in the presence of taxanes, which reconciles incompatible observations in cells [9] and in vitro [10]. We propose a model explaining DCX specificity for different MT geometries based on structural changes induced by GTP hydrolysis that decreases the spacing between adjacent tubulin dimers [11]. Our data are consistent with a unique mode of MT interaction in which DCX specifically recognizes this compacted GDP-like MT lattice.

Background: Reactive astrogliosis and microgliosis are coordinated responses to CNS insults and are pathological hallmarks of traumatic brain injury (TBI). In these conditions, persistent reactive gliosis can impede tissue repopulation and limit neurogenesis. Thus, modulating this phenomenon has been increasingly recognized as potential therapeutic approach., Methods: In this study, we investigated the potential of the flavonoid agathisflavone to modulate astroglial and microglial injury responses and promote neurogenesis in the subventricular zone (SVZ) neurogenic niche. Agathisflavone, or the vehicle in controls, was administered directly into the lateral ventricles in postnatal day (P)8-10 mice by twice daily intracerebroventricular (ICV) injections for 3 days, and brains were examined at P11., Results: In the controls, ICV injection caused glial reactivity along the needle track, characterised immunohistochemically by increased astrocyte expression of glial fibrillary protein (GFAP) and the number of Iba-1+ microglia at the lesion site. Treatment with agathisflavone decreased GFAP expression, reduced both astrocyte reactivity and the number of Iba-1 + microglia at the core of the lesion site and the penumbra, and induced a 2-fold increase on the ratio of anti-inflammatory CD206+ to pro-inflammatory CD16/32+ microglia. Notably, agathisflavone increased the population of neuroblasts (GFAP+ type B cells) in all SVZ microdomains by up to double, without significantly increasing the number of neuronal progenitors (DCX+)., Conclusions: Although future studies should investigate the underlying molecular mechanisms driving agathisflavone effects on microglial polarization and neurogenesis at different timepoints, these data indicate that agathisflavone could be a potential adjuvant treatment for TBI or central nervous system disorders that have reactive gliosis as a common feature.

High-fat diet (HFD) induced obesity is associated with depression-related behavioral and neurogenic changes and may lead to cognitive impairment. Fluoxetine (FXT), the most commonly used antidepressant, may alleviate depressive symptoms by increasing neurogenesis, but the potential efficacy of FXT for HFD-induced cognitive deficits is unclear. In this study, we established an obese HFD mouse model by feeding three-week-old male C57BL/6N mice with a chronic HFD for 18 weeks, then assessed adipose tissue morphology by magnetic resonance imaging and histopathology, assessed cognitive function by Morris water maze and novel object recognition tests, and detected DCX + and BrdU + expression in the hippocampal dentate gyrus (DG) region by immunofluorescence bioassay. Western blot detected brain-derived neurotrophic factor (BDNF) levels and CREB-BDNF pathway-related genes were assayed by Quantitative RT-PCR. The results of the study showed that HFD contributes to obesity and cognitive deficits, and more importantly, it also reduces BDNF expression and neurogenesis levels in the hippocampus. Subsequently, we found that treatment with FXT (10 mg/kg/day) ameliorated chronic HFD-induced cognitive deficits and increased the expression of Nestin, BrdU + , and DCX + in the DG, restored BDNF expression in the hippocampus and increased the expression of genes related to CREB , BDNF , NGF , and MAPK1 . In conclusion, our data elucidated that FXT ameliorates cognitive deficits and reduces chronic HFD-induced neurogenesis by restoring BDNF expression and CREB-BDNF signaling, this provides a good basis and scientific significance for future research on the clinical treatment of obesity.

Epigenetic modifications play a pivotal role in the process of neurogenesis. Among these modifications, reversible acetylation fine-tunes gene expression for both embryonic and adult neurogenesis. The CBP/KAT3A and its paralogue p300/KAT3B are well-known lysine acetyltransferases with transcriptional coactivation ability that engage in neural plasticity and memory. The exclusive role of their KAT activity in neurogenesis and memory could not be addressed due to the absence of a p300/CBP modulator, which can cross the blood-brain barrier. Previous work from our laboratory has shown that a small molecule activator, TTK21, specific to CBP/p300, when conjugated to glucose-derived carbon nanospheres (CSP), is efficiently delivered to the mouse brain and could induce dendritic branching and extend long-term memory. However, the molecular mechanisms of p300 acetyltransferase activity-dependent enhanced dendritogenesis are yet to be understood. Here, we report that CSP-TTK21 treatment to primary neuronal culture derived from mouse embryo enhances the expression of five critical genes: Neurod1 (central nervous system development), Tubb3 (immature neural marker), Camk2a (synaptic plasticity and LTP), Snap25 (spine morphogenesis plasticity), and Scn2a (propagation of the action potential). Activation of these genes by inducing the p300/CBP KAT activity presumably promotes the maturation and differentiation of adult neuronal progenitors and thereby the formation of long and highly branched doublecortin-positive functional neurons in the subgranular zone of the dentate gyrus.

Stem cell transplantation offers a promising therapy that can be administered days, weeks, or months after a stroke. We recognize 2 major mitigating factors that remain unresolved in cell therapy for stroke, notably: (1) well-defined donor stem cells and (2) mechanism of action. To this end, we advance the use of ProtheraCytes, a population of non-adherent CD34+ cells derived from human peripheral blood and umbilical cord blood, which have been processed under good manufacturing practice, with testing completed in a phase 2 clinical trial in post-acute myocardial infarction (NCT02669810). We also reveal a novel mechanism whereby ProtheraCytes secrete growth factors and extracellular vesicles (EVs) that are associated with angiogenesis and vasculogenesis. Our recent data revealed that intranasal transplantation of ProtheraCytes at 3 days after experimentally induced stroke in adult rats reduced stroke-induced behavioral deficits and histological damage up to 28 days post-stroke. Moreover, we detected upregulation of human CD63+ EVs in the ischemic brains of stroke animals that were transplanted with ProtheraCytes, which correlated with increased levels of DCX-labeled neurogenesis and VEGFR1-associated angiogenesis and vasculogenesis, as well as reduced Iba1-marked inflammation. Altogether, these findings overcome key laboratory-to-clinic translational hurdles, namely the identification of well-characterized, clinical grade ProtheraCytes and the elucidation of a potential CD63+ EV-mediated regenerative mechanism of action. We envision that additional translational studies will guide the development of clinical trials for intranasal ProtheraCytes allografts in stroke patients, with CD63 serving as a critical biomarker., (© The Author(s) 2024. Published by Oxford University Press.)

Estrone and estradiol differentially modulate neuroplasticity and cognition. How they influence the maturation of new neurons in the adult hippocampus, however, is not known. The present study assessed the effects of estrone and estradiol on the maturation timeline of neurogenesis in the dentate gyrus (DG) of ovariectomized (a model of surgical menopause) young adult Sprague-Dawley rats using daily subcutaneous injections of 17β-estradiol, estrone or vehicle. Rats were injected with a DNA synthesis marker, 5-bromo-2-deoxyuridine (BrdU), and were perfused 1, 2, or 3 weeks after BrdU injection and daily hormone treatment. Brains were sectioned and processed for various markers including: sex-determining region Y-box 2 (Sox2), glial fibrillary acidic protein (GFAP), antigen kiel 67 (Ki67), doublecortin (DCX), and neuronal nuclei (NeuN). Immunofluorescent labeling or co-labelling of BrdU with Sox2 (progenitor cells), Sox2/GFAP (neural progenitor cells), Ki67 (cell proliferation), DCX (immature neurons), NeuN (mature neurons) was used to examine the trajectory and maturation of adult-born neurons over time. Estrogens had early (1 week of exposure) effects on different stages of neurogenesis (neural progenitor cells, cell proliferation and early maturation of new cells into neurons) but these effects were less pronounced after prolonged treatment. Estradiol enhanced, whereas estrone reduced cell proliferation after 1 week but not after longer exposure to either estrogen. Both estrogens increased the density of immature neurons (BrdU/DCX-ir) after 1 week of exposure compared to vehicle treatment but this increased density was not sustained over longer durations of treatments to estrogens, suggesting that the enhancing effects of estrogens on neurogenesis were short-lived. Longer duration post-ovariectomy, without treatments with either of the estrogens, was associated with reduced neural progenitor cells in the DG. These results demonstrate that estrogens modulate several aspects of adult hippocampal neurogenesis differently in the short term, but may lose their ability to influence neurogenesis after long-term exposure. These findings have potential implications for treatments involving estrogens after surgical menopause., (© 2024 The Author(s). Hippocampus published by Wiley Periodicals LLC.)

Neurogenesis occurs throughout life in the hippocampus of the brain, and many environmental toxicants inhibit neural stem cell (NSC) function and neuronal generation. Bisphenol-A (BPA), an endocrine disrupter used for surface coating of plastic products causes injury in the developing and adult brain; thus, many countries have banned its usage in plastic consumer products. BPA analogs/alternatives such as bisphenol-F (BPF) and bisphenol-S (BPS) may also cause neurotoxicity; however, their effects on neurogenesis are still not known. We studied the effects of BPF and BPS exposure from gestational day 6 to postnatal day 21 on neurogenesis. We found that exposure to non-cytotoxic concentrations of BPF and BPS significantly decreased the number/size of neurospheres, BrdU + (proliferating NSC marker) and MAP-2 + (neuronal marker) cells and GFAP + astrocytes in the hippocampus NSC culture, suggesting reduced NSC stemness and self-renewal and neuronal differentiation and increased gliogenesis. These analogs also reduced the number of BrdU/Sox-2 + , BrdU/Dcx + , and BrdU/NeuN + co-labeled cells in the hippocampus of the rat brain, suggesting decreased NSC proliferation and impaired maturation of newborn neurons. BPF and BPS treatment increases BrdU/cleaved caspase-3 + cells and Bax-2 and cleaved caspase protein levels, leading to increased apoptosis in hippocampal NSCs. Transmission electron microscopy studies suggest that BPF and BPS also caused degeneration of neuronal myelin sheath, altered mitochondrial morphology, and reduced number of synapses in the hippocampus leading to altered cognitive functions. These results suggest that BPF and BPS exposure decreased the NSC pool, inhibited neurogenesis, induced apoptosis of NSCs, caused myelin degeneration/synapse degeneration, and impaired learning and memory in rats., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterised by cognitive dysfunction, memory loss and mood changes. Hippocampal neurogenesis has been suggested to play a role in learning and memory. Neurokinin 3 receptor (NK3R) has been shown to be prevalent in the hippocampus region. The aim of the project was to investigate the role of hippocampal neurogenesis in the promnestic effects of NK3R agonist administration in an amyloid beta-induced AD rat model. Wistar albino rats were divided into control, Alzheimer, NK3R agonist and Alzheimer + NK3R agonist groups. The open field (OF) test and Morris water maze (MWM) test were performed for locomotor activity and memory analysis. Peptide gene expression levels (Nestin, DCX, Neuritin, MASH1, Neun, BDNF) were analysed by quantitative reverse transcription polymerase chain reaction (RT-PCR). In the OF test, the group-time relationship was found to be statistically different in the parameters of distance travelled and percentage of movement (p < 0.05). In MWM, the time to reach the platform and the time spent in the target quadrant were statistically significant between the groups (p < 0.05). Statistically significant differences were observed in gene expression levels (Nestin, DCX, Neuritin, MASH1) in the hippocampal tissue of rats between the groups (p < 0.05). NK3 receptor agonism favourably affected hippocampal neurogenesis in AD model rats. It was concluded that NK3 receptor agonism in the hippocampus, which is the first affected region in the physiopathology of AD, may be effective in both the formation of neural precursor cells and the reduction of neuronal degeneration. The positive effect of NK3R on cognitive functions may be mediated by hippocampal neurogenesis., (© 2024 International Society for Developmental Neuroscience.)

Background: Adult hippocampal neurogenesis has been extensively characterized in rodent models, but its existence in humans remains controversial. We sought to assess the phenomenon in postmortem human hippocampal samples by combining spatial transcriptomics and multiplexed fluorescent in situ hybridization., Methods: We computationally examined the spatial expression of various canonical neurogenesis markers in postmortem dentate gyrus (DG) sections from young and middle-aged sudden-death males. We conducted in situ assessment of markers expressed in neural stem cells, proliferative cells, and immature granule neurons in postmortem DG sections from infant, adolescent, and middle-aged males., Results: We examined frozen DG tissue from infant ( n = 1, age 2 yr), adolescent ( n = 1, age 16 yr), young adult ( n = 2, mean age 23.5 yr), and middle-aged ( n = 2, mean age 42.5 yr) males, and frozen-fixed DG tissue from middle-aged males ( n = 6, mean age 43.5 yr). We detected very few cells expressing neural stem cell and proliferative markers in the human DG from childhood to middle age. However, at all ages, we observed a substantial number of DG cells expressing the immature neuronal marker DCX . Most DCX + cells displayed an inhibitory phenotype, while the remainder were non-committed or excitatory in nature., Limitations: The study was limited by small sample sizes and included samples only from males., Conclusion: Our findings indicate very low levels of hippocampal neurogenesis throughout life and the existence of a local reserve of plasticity in the adult human hippocampus. Overall, our study provides important insight into the distribution and phenotype of cells expressing neurogenesis markers in the adult human hippocampus., Competing Interests: Competing interests:: None declared., (© 2024 CMA Impact Inc. or its licensors.)

Our previous study demonstrated that the acute high-dose-rate (3.3 Gy/min) γ-ray irradiation (γ-irradiation) of postnatal day-3 (P3) mice with 5 Gy induced depression and drastic neuropathological changes in the dentate gyrus of the hippocampus of adult mice. The present study investigated the effects of chronic low-dose-rate (1.2 mGy/h) γ-irradiation from P3 to P180 with a cumulative dose of 5 Gy on animal behaviour, hippocampal cellular change, and miRNA and mRNA expression in the hippocampus and blood in female mice. The radiation exposure did not significantly affect the animal's body weight, and neuropsychiatric changes such as anxiety and depression were examined by neurobehavioural tests, including open field, light-dark box, elevated plus maze, tail suspension, and forced swim tests. Immunohistochemical staining did not detect any obvious loss of mature and immature neurons (NeuN and DCX) or any inflammatory glial response (IBA1, GFAP, and PDGFRα). Nevertheless, γH2AX foci in the stratum granulosum of the dentate gyrus were significantly increased, suggesting the chronic low-dose-rate irradiation induced persistent DNA damage foci in mice. miRNA sequencing and qRT-PCR indicated an increased expression of miR-448-3p and miR-361-5p but decreased expression of miR-193a-3p in the mouse hippocampus. Meanwhile, mRNA sequencing and qRT-PCR showed the changed expression of some genes, including Fli1 , Hs3st5 , and Eif4ebp2 . Database searching by miRDB and TargetScan predicted that Fli1 and Hs3st5 are the targets of miR-448-3p, and Eif4ebp2 is the target of miR-361-5p. miRNA/mRNA sequencing and qRT-PCR results in blood showed the increased expression of miR-6967-3p and the decreased expression of its target S1pr5 . The interactions of these miRNAs and mRNAs may be related to the chronic low-dose-rate radiation-induced persistent DNA damage.

Major depressive disorder (MDD) is a common disease affecting 300 million people worldwide. The existing drugs are ineffective for approximately 30% of patients, so it is urgent to develop new antidepressant drugs with novel mechanisms. Here, we found that norisoboldine (NOR) showed an antidepressant efficacy in the chronic social defeat stress (CSDS) depression model in the tail suspension, forced swimming, and sucrose consumption tests. We then utilized the drug-treated CSDS mice paradigm to segregate and gain differential protein groups of CSDS versus CON (CSDS CON ), imipramine (IMI)-treated versus CSDS (IMI CSDS ), and NOR-treated versus CSDS (NOR CSDS ) from the prefrontal cortex. These protein expression alterations were first analyzed by ANOVA with p < 0.05. The protein cluster 1 and cluster 3, in which the pattern of protein levels similar to the mood pattern, showed enrichment in functions and localizations related to mitochondrion, ribosome and synapses. Further GO analysis of the common proteins for NOR CSDS groups and NOR IMI groups supported the findings from ANOVA analysis. We employed Protein-Protein interaction (PPI) analysis to examine the proteins of NOR CSDS and NOR IMI, revealing an enrichment of the proteins associated with the mitochondrial ribosomal and synaptic functions. Further independent analysis using parallel reaction monitoring (PRM) revealed that Cox7c, Mrp142, Naa30, Ighm, Apoa4, Ssu72, Mrps30, Apoh, Acbd5, and Cdv3, exhibited regulation in the NOR-treated group to support the homeostasis of mitochondrial functions. Additionally, Dcx, Arid1b, Rnf112, and Fam3c, were also observed to undergo modulation in the NOR-treated groups to support the synaptic formation and functions. These findings suggest that the proteins involved in depression treatment exert effects in strengthen the mitochondrial and synaptic functions in the mice PFC. Western blot analysis supported the data that the levels of Mrpl42, Cox7c, Naa30, Rnf112, Dcx Apoa4, Apoh and Fam3c were altered in the CSDS mice, and rescued by NOR treatment, supporting the PRM data. NOR treatment also rescued the NLRP3 inflammasome activation in CSDS mice. In summary, the current proteomic research conducted on the prefrontal cortex has provided valuable insights into the specific and shared molecular mechanisms underlying pathophysiology and treatment to CSDS-induced depression, shedding light on the therapeutic effects of Norisoboldine., (© 2024. The Author(s).)

Peroxisome proliferator-activated receptors (PPARs) have emerged as a promising target for the treatment of various neurodegenerative disorders. Studies have shown that both PPAR α & γ individually modulate various pathophysiological events like neuroinflammation and insulin resistance, which are known to variedly affect neurogenesis. Our study aimed to evaluate the effect of saroglitazar (SGZR), a dual PPAR agonist, on adult neurogenesis and spatial learning and memory, in intracerebroventricular streptozotocin (ICV STZ)-induced dementia in rats. We have found that SGZR at the dose of 4 mg/kg per oral showed significant improvement in learning and memory compared to ICV STZ-treated rats. A substantial increase in neurogenesis was observed in the subventricular zone (SVZ) and the dentate gyrus (DG), as indicated by an increase in the number of 5-bromo-2'-deoxyuridine (BrdU) + cells, BrdU + nestin + cells, and doublecortin (DCX) + cells. Treatment with SGZR also decreased the active form of glycogen synthase kinase 3β (GSK3β) and hence enhanced the nuclear translocation of the β-catenin. Enhanced expression of Wnt transcription factors and target genes indicates that the up-regulation of Wnt signaling might be involved in the observed increase in neurogenesis. Hence, it can be concluded that the SGZR enhances memory functions and adult neurogenesis via the upregulation of Wnt β-catenin signaling in ICV STZ-treated rats.

Scope: Garlic extract (GE) has been shown to ameliorate hyperglycemia in diabetic rats (DRs) by increasing insulin production. However, the mechanism through which it exerts its effects remains unclear. Here, it investigates the molecular process and the origin of regenerating β-cell in rats with streptozotocin (STZ)-induced diabetes in response to GE., Methods and Results: In this study, quantitative RT-PCR (qRT-PCR), western blotting, and immunohistochemical analysis are carried out after pancreas isolation. These findings show that 1 week of GE treatment increases the expression of the endocrine progenitor cell markers Neurogenin3 (Neurog3), pancreatic and duodenal homeobox 1 (Pdx1), neurogenic differentiation factor 1 (Neurod1), paired box proteins (Pax)4, V-maf musculoaponeurotic fibrosarcoma oncogene homolog B (Mafb), and NK homeobox factors (Nkx)6-1 in STZ-induced DRs. Continuation with GE treatment for 8 weeks causes the expression of the mature β-cell markers insulin(Ins)2, urocortin3 (Ucn3), and glucose transporter 2 (Glut2) to peak. Comprehensive examination of the islet through immunohistochemical analysis reveals the presence of a heterogeneous cell population including INS+/GLUT2- and INS+/GLUT2+ β-cell subpopulations with few bihormonal INS+/GCG+ cells after 4 weeks. By week 8, islet architecture is reestablished, and glucose-stimulated insulin secretion was restored through the upregulation of Ucn3., Conclusion: GE induces β-cell neogenesis in DRs and restores islet architecture. The newly formed mature β-like cells could have originated through the differentiation of endocrine progenitor cells as well as α- to β-cell transdifferentiation., (© 2024 Wiley‐VCH GmbH.)

Traumatic brain injury (TBI) is an incurable and overwhelming disease accompanied with serve disability and huge financial burden, where the overproduced reactive oxygen species (ROS) can exacerbate the secondary injury, leading to massive apoptosis of neurons. In this study, β-cyclodextrin (CD)-capped hyperbranched polymers containing selenium element (HSE-CD) were crosslinked with CD-modified hyaluronic acid (HA-CD) and amantadine-modified hyaluronic acid (HA-AD) to obtain a ROS-responsive ointment (R-O). The structures of synthesized polymers were characterized with 1 H nuclear magnetic resonance, and the properties of ointment were investigated with rheology and antioxidation. Compared to non-ROS-responsive ointment (N-O), the R-O ointment had stronger efficiency in decreasing the ROS level in BV2 cells in vitro. In a controlled rat cortical impact (CCI) model, the R-O ointment could relieve the DNA damage and decrease apoptosis in injured area via reducing the ROS level. Besides, after the R-O treatment, the rats showed significantly less activated astrocytes and microglia, a lower level of pro-inflammatory cytokines and a higher ratio of M2/M1 macrophage and microglia. Moreover, compared to the TBI group the R-O ointment promoted the doublecortin (DCX) expression and tissue structure integrity around the cavity, and promoted the recovery of nerve function post TBI. STATEMENT OF SIGNIFICANCE: Traumatic brain injury (TBI) is an incurable and overwhelming disease, leading to severe disability and huge social burden, where reactive oxygen species (ROS) are considered as one of the most significant factors in the secondary injury of TBI. A ROS responsive supramolecular ointment containing di-selenide bonds was injected in rats with controlled cortical impact. It relieved the DNA damage and decreased apoptosis in the injured area via reducing the ROS levels, downregulated neuroinflammation, and improved neurological recovery of TBI in vivo. This designed self-adaptive biomaterial effectively regulated the pathological microenvironment in injured tissue, and achieved better therapeutic effect., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Neural stem/progenitor cells (NSPCs) persist in the mammalian subventricular zone (SVZ) throughout life, responding to various pathophysiological stimuli and playing a crucial role in central nervous system repair. Although numerous studies have elucidated the role of stanniocalcin 2 (STC2) in regulating cell differentiation processes, its specific function in NSPCs differentiation remains poorly understood. Clarifying the role of STC2 in NSPCs is essential for devising novel strategies to enhance the intrinsic potential for brain regeneration postinjury. Our study revealed the expression of STC2 in NSPCs derived from the SVZ of the C57BL/6N mouse. In cultured SVZ-derived NSPCs, STC2 treatment significantly increased the number of Tuj1 and DCX-positive cells. Furthermore, STC2 injection into the lateral ventricle promoted the neuronal differentiation of NSPCs and migration to the olfactory bulb. Conversely, the STC2 knockdown produced the opposite effect. Further investigation showed that STC2 treatment enhanced AKT phosphorylation in cultured NSPCs, whereas STC2 inhibition hindered AKT activation. Notably, the neuronal differentiation induced by STC2 was blocked by the AKT inhibitor GSK690693, whereas the AKT activator SC79 reversed the impact of STC2 knockdown on neuronal differentiation. Our findings indicate that enhancing STC2 expression in SVZ-derived NSPCs facilitates neuronal differentiation, with AKT regulation potentially serving as a key intracellular target of STC2 signaling.

Background: Presence of nerves in tumours, by axonogenesis and neurogenesis, is gaining increased attention for its impact on cancer initiation and development, and the new field of cancer neuroscience is emerging. A recent study in prostate cancer suggested that the tumour microenvironment may influence cancer progression by recruitment of Doublecortin (DCX)-expressing neural progenitor cells (NPCs). However, the presence of such cells in human breast tumours has not been comprehensively explored., Methods: Here, we investigate the presence of DCX-expressing cells in breast cancer stromal tissue from patients using Imaging Mass Cytometry. Single-cell analysis of 372,468 cells across histopathological images of 107 breast cancers enabled spatial resolution of neural elements in the stromal compartment in correlation with clinicopathological features of these tumours. In parallel, we established a 3D in vitro model mimicking breast cancer neural progenitor-innervation and examined the two cell types as they co-evolved in co-culture by using mass spectrometry-based global proteomics., Findings: Stromal presence of DCX + cells is associated with tumours of higher histological grade, a basal-like phenotype, and shorter patient survival in tumour tissue from patients with breast cancer. Global proteomics analysis revealed significant changes in the proteomic landscape of both breast cancer cells and neural progenitors in co-culture., Interpretation: These results support that neural involvement plays an active role in breast cancer and warrants further studies on the relevance of nerve elements for tumour progression., Funding: This work was supported by the Research Council of Norway through its Centre of Excellence funding scheme, project number 223250 (to L.A.A), the Norwegian Cancer Society (to L.A.A. and H.V.), the Regional Health Trust Western Norway (Helse Vest) (to L.A.A.), the Meltzer Research Fund (to H.V.) and the National Institutes of Health (NIH)/NIGMS grant R01 GM132129 (to J.A.P.)., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Modulation of in vivo adult neurogenesis (AN) is an evolving concept in managing neurodegenerative diseases. CDRI-08, a bacoside-enriched fraction of Bacopa monnieri, has been demonstrated for its neuroprotective actions, but its effect on AN remains unexplored. This article describes the status of AN by monitoring neuronal stem cells (NSCs) proliferation, differentiation/maturation markers and BDNF-TrkB levels (NSCs signalling players) vs. the level of neurodegeneration and their modulations by CDRI-08 in the hippocampal dentate gyrus (DG) of male rats with moderate grade hepatic encephalopathy (MoHE). For NSC proliferation, 10 mg/kg b.w. 5-bromo-2'-deoxyuridine (BrdU) was administered i.p. during the last 3 days, and for the NSC differentiation study, it was given during the first 3 days to the control, the MoHE (developed by 100 mg/kg b.w. of thioacetamide i.p. up to 10 days) and to the MoHE male rats co-treated with 350 mg/kg b.w. CDRI-08. Compared with the control rats, the hippocampus DG region of MoHE rats showed significant decreases in the number of Nestin + /BrdU + and SOX2 + /BrdU + (proliferating) and DCX + /BrdU + and NeuN + /BrdU + (differentiating) NSCs. This was consistent with a similar decline in BDNF + /TrkB + NSCs. However, all these NSC marker positive cells were observed to be recovered to their control levels, with a concordant restoration of total cell numbers in the DG of the CDRI-08-treated MoHE rats. The findings suggest that the restoration of hippocampal AN by CDRI-08 is consistent with the recovery of BDNF-TrkB-expressing NSCs in the MoHE rat model of neurodegeneration., (© 2024 International Society for Developmental Neuroscience.)

Objective: To make a preliminary investigation of the effect of the immune pathway mediated by live Lacticaseibacillus paracasei N1115 on the development of primary hippocampal neurons cultured in vitro ., Methods: Live Lacticaseibacillus paracasei N1115 suspension of an appropriate concentration was used as the experimental group. Peptidoglycan (PGN) and lipopolysaccharide (LPS) were used as positive controls, and RPMI1640 medium served as the blank control. These were co-cultured with RAW264.7 cells to obtain the co-culture mediums and the total cellular RNA, and to measure the expression and secretion of cytokines. After centrifugation, the supernatants were co-cultured with primary hippocampal neurons at appropriate ratios. The co-culture mediums were collected, and the total cellular RNA was extracted to measure the expression of genes related to synaptic development in neurons. Following immunofluorescence staining of the primary hippocampal neurons, the presynaptic and presynaptic membrane-associated proteins, including synaptophysin (SYP) and the postsynaptic density protein 95 (PSD95), and neuronal cell maturation markers, including microtubule-associated protein 2 (MAP-2), and doublecortin (DCX) were quantitatively analyzed. Additionally, the morphological development of the neurons were measured., Results: Compared with the blank control, the mRNA expression levels of interleukin (IL)-6 and tumor necrosis factor- α (TNF-α) increased by 7471% and 926%, respectively, after the RAW264.7 cells were treated with live Lacticaseibacillus paracasei N1115, while their secretion levels increased by 184.16 pg/mL and 12320.76 pg/mL, respectively, all showing statistically significant differences ( P <0.05). The activation ability of N1115 live bacteria was stronger than that of PGN but weaker than that of LPS, showing statistically significant differences ( P <0.05). Compared with the blank control, following the intervention with the supernatant from the co-culture of N1115 live bacteria and RAW264.7 cells, the viability of primary hippocampal neurons in the 10% supernatant intervention group increased by 19.25%, showing statistically significant differences ( P <0.05), and the mRNA expression of SYP and PSD95 increased by 137% and 159%, respectively, showing statistically significant differences ( P <0.05). The total neurite length (489.88 μm) of the neurons of the group intervened with the supernatant of N1115 live bacteria was increased compared to that of the blank control group (381.51 μm), and the cell body area (2092.22 μm 2 ), maximum neurite length (184.78 μm), total neurite length, average neurite length (108.38 μm), and branching points (4.84 s) were higher than those in the two positive control groups, showing statistically significant differences ( P <0.05)., Conclusion: Lacticaseibacillus paracasei N1115 can significantly activate the immune regulatory function of macrophages, thereby promoting the morphological development and synaptic function of nerve cells., Competing Interests: 利益冲突　所有作者均声明不存在利益冲突, (© 2024《四川大学学报（医学版）》编辑部 版权所有Copyright ©2024 Editorial Office of Journal of Sichuan University (Medical Sciences).)

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline and memory loss. Imipramine, a tricyclic antidepressant, has potent anti-inflammatory and antioxidant properties in the central nervous system. The aim of this study was to investigate the neuroprotective effects of imipramine on streptozotocin (STZ)-induced memory impairment. Male Wistar rats received an intracerebroventricular injection of STZ (3 mg/kg, 3 μl/ventricle) using the stereotaxic apparatus. The Morris water maze and passive avoidance tests were used to evaluate cognitive functions. 24 h after the STZ injection, imipramine was administered intraperitoneally at doses of 10 or 20 mg/kg for 14 consecutive days. The mRNA and protein levels of neurotrophic factors (BDNF and GDNF) and pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α) were measured in the hippocampus using real-time PCR and ELISA techniques, respectively. In addition, real-time PCR was used to evaluate the mRNA levels of markers associated with neurogenesis (Nestin, DCX, and Ki67) and mitochondrial biogenesis (PGC-1α, NRF-1, and TFAM). The results showed that imipramine, especially at a dose of 20 mg/kg, effectively improved STZ-induced memory impairment. This improvement was associated with an increase in neurogenesis and neurotrophic factors and a decrease in neuroinflammation and mitochondrial biogenesis dysfunction. Based on these results, imipramine appears to be a promising therapeutic option for improving cognitive functions in neurodegenerative diseases such as AD., Competing Interests: Declarations of interest none., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

It has been demonstrated that an enriched environment (EE) treatment can alter neuroplasticity in neurodegenerative diseases. However, the role of EE treatment in ischemic stroke remains unclear. Previous findings have revealed that EE treatment can promote cerebral activin-receptor-like-kinase-5 (ALK5) expression after cerebral ischemia/reperfusion (I/R) injury. ALK5 has been identified as a potential mediator of neuroplasticity through its modulation of Smad2/3 and Gadd45β. Therefore, the aim of this study was to investigate whether EE treatment could promote neurofunctional recovery by regulating the ALK5/Smad2/3/Gadd45β pathway. The study utilized the rat model of middle cerebral artery occlusion/reperfusion (MCAO/R). The ALK5/Smad2/3/Gadd45β signaling pathway changes were evaluated using western blotting (WB). Brain injury was assessed by infarct volume and neurobehavioral scores. The effect of EE treatment on neurogenesis was evaluated using Doublecortin (DCX) and Nestin, axonal plasticity with biotinylated dextran amine (BDA) nerve tracing, and dendritic plasticity was assessed using Golgi-Cox staining. EE treatment has been demonstrated to modulate the Smad2/3/Gadd45β pathway by regulating the expression of ALK5. The protective effects of EE treatment on brain infarct volume, neurological function, newborn neurons, dendritic and axonal plasticity following cerebral I/R injury were counteracted by ALK5 silencing. EE treatment can enhance neurofunctional recovery after cerebral I/R injury, which is achieved by regulating the ALK5/Smad2/3/Gadd45β signaling pathway to promote neuroplasticity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Promoting neural cell proliferation may represent an important strategy for enhancing brain repair after developmental brain injury. The present study aimed to assess the effects of melatonin on cell proliferation after an ischemic injury in the developing hippocampus, focusing on cell cycle dynamics. After in vivo neonatal hypoxia-ischemia (HI), hippocampal cell cycle dynamics were assessed by flow cytometry, together with histological evaluation of dentate gyrus cellularity and proliferation. Melatonin significantly increased the number of proliferating cells in the G2/M phase as well as the proliferating cell nuclear antigen (PCNA) and doublecortin (DCX) labeling reduced by HI. In vivo BrdU labeling revealed a higher BrdU-positivity in the dentate gyrus of ischemic rats treated with melatonin, an effect followed by increased cellularity and preserved hippocampal tissue integrity. These results indicate that the protective effect of melatonin after ischemic injury in neonatal rats may rely on the modulation of cell cycle dynamics of newborn hippocampal cells and increased cell proliferation., (© 2024. The Author(s).)

TALE-homeodomain proteins function as components of heteromeric complexes that contain one member each of the PBC and MEIS/PREP subclasses. We recently showed that MEIS2 cooperates with the neurogenic transcription factor PAX6 in the control of adult subventricular zone (SVZ) neurogenesis in rodents. Expression of the PBC protein PBX1 in the SVZ has been reported, but its functional role(s) has not been investigated. Using a genetic loss-of-function mouse model, we now show that Pbx1 is an early regulator of SVZ neurogenesis. Targeted deletion of Pbx1 by retroviral transduction of Cre recombinase into Pbx2-deficient SVZ stem and progenitor cells carrying floxed alleles of Pbx1 significantly reduced the production of neurons and increased the generation of oligodendrocytes. Loss of Pbx1 expression in neuronally committed neuroblasts in the rostral migratory stream in a Pbx2 null background, by contrast, severely compromised cell survival. By chromatin immunoprecipitation from endogenous tissues or isolated cells, we further detected PBX1 binding to known regulatory regions of the neuron-specific genes Dcx and Th days or even weeks before the respective genes are expressed during the normal program of SVZ neurogenesis, suggesting that PBX1 might act as a priming factor to mark these genes for subsequent activation. Collectively, our results establish that PBX1 regulates adult neural cell fate determination in a manner beyond that of its heterodimerization partner MEIS2.

Many genes involved in brain development have been associated with human neurodevelopmental disorders, but underlying pathophysiological mechanisms remain undefined. Human genetic and mouse behavioral analyses suggest that ENGRAILED-2 (EN2) contributes to neurodevelopmental disorders, especially autism spectrum disorder. In mouse, En2 exhibits dynamic spatiotemporal expression in embryonic mid-hindbrain regions where monoamine neurons emerge. Considering their importance in neuropsychiatric disorders, we characterized monoamine systems in relation to forebrain neurogenesis in En2-knockout (En2-KO) mice. Transmitter levels of serotonin, dopamine and norepinephrine (NE) were dysregulated from Postnatal day 7 (P7) to P21 in En2-KO, though NE exhibited the greatest abnormalities. While NE levels were reduced ∼35% in forebrain, they were increased 40 -: 75% in hindbrain and cerebellum, and these patterns paralleled changes in locus coeruleus (LC) fiber innervation, respectively. Although En2 promoter was active in Embryonic day 14.5 -: 15.5 LC neurons, expression diminished thereafter and gene deletion did not alter brainstem NE neuron numbers. Significantly, in parallel with reduced NE levels, En2-KO forebrain regions exhibited reduced growth, particularly hippocampus, where P21 dentate gyrus granule neurons were decreased 16%, suggesting abnormal neurogenesis. Indeed, hippocampal neurogenic regions showed increased cell death (+77%) and unexpectedly, increased proliferation. Excess proliferation was restricted to early Sox2/Tbr2 progenitors whereas increased apoptosis occurred in differentiating (Dcx) neuroblasts, accompanied by reduced newborn neuron survival. Abnormal neurogenesis may reflect NE deficits because intra-hippocampal injections of β-adrenergic agonists reversed cell death. These studies suggest that disruption of hindbrain patterning genes can alter monoamine system development and thereby produce forebrain defects that are relevant to human neurodevelopmental disorders.