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Objective To investigate the effects of lycopene (Lyc) on hippocampal inflammation, social deficits and repetitive stereotyped behaviors in BTBR T+ Itpr3tf/J autistic mice (BTBR, a mouse strain showing lower sociability as a model for autism spectrum disorder). Methods Adult male C57BL/6J (C57) and BTBR mice aged 7-8 weeks were randomly divided into (n=8): C57+Veh group, C57+Lyc group, BTBR+Veh group and BTBR+Lyc group. The mice from the C57+Lyc group and BTBR+Lyc group were given 20 mg/kg Lyc by gavage once a day for 7 d, and those of the C57+Veh group and BTBR+Veh mice were given equal volume of corn oil. Then three-chamber social test, male-female reciprocal social interactions, self-grooming, marble buying, open field test, object recognition test, nest building, and Y-maze test were conducted in these mice. Immediately after the behavioral tests, the mice were sacrificed and their brain samples were harvested for RT-qPCR and Western blotting. Results Behavioral results showed that in the three-chamber social test, the mice of the BTBR+Veh group spent longer time in the chamber with the object, showing much curiosity about the object (P < 0.05), while the mice after Lyc treatment showed a preference for strange mice (P < 0.05). In the self-grooming and marble burying behavior test, the BTBR+Veh group showed markedly increased repeated stereotyped behaviors than the C57+Veh group mice (P < 0.05), which could be alleviated by Lyc treatment (P < 0.05). The hippocampal expression of NLRP3 at mRNA and protein levels (P < 0.05), and the mRNA levels of IL-1β, IL-18, IL-6, NF-κB, and TNF-α were significantly increased in the BTBR+Veh group mice when compared with the C57+Veh group mice, and Lyc treatment obviously reversed above changes (P < 0.05). Conclusion Lyc treatment improves three-chamber social deficits and repetitive stereotyped behaviors in BTBR mice by reducing NLRP3 inflammasome in the hippocampus of BTBR mice.

Objective To investigate the effects of neonatal aluminum hydroxide [Al(OH)3] exposure in mice on social behavior and cognitive function in their adulthood. Methods Sixteen newborn C57BL/6 male mice of SPF class with body mass of 2~3 g were divided into 2 groups (n=8): the normal control group (C57+Sal) and the neonatal Al(OH)3 treated group [C57+ Al(OH)3]. Al(OH)3 was administered by intramuscular injection at doses of 290, 75, 100, 110 and 50 μg/kg on postnatal days of 3, 5, 7, 10 and 12, respectively. The control group received intramuscular injections of equal volumes of saline. The open field test, light-dark box test, elevated plus maze test were used to evaluate the motor function and anxiety-like behavior of mice; The grooming test and marble burying test were used to assess the repetitive stereotypic behavior of mice; The three-chamber social test was used to evaluate the social ability of mice; The novel object recognition, Y-maze and nest building test were used to evaluate the short-term memory function and cognitive function of mice; The Morris water maze test was used to evaluate the spatial memory ability and learning ability of mice. Sox2, GFAP, PCNA immunofluorescence assay was used to detect the number of neural stem cells and proliferating cells in the hippocampus; NeuN, S100β, Iba1 immunofluorescence assay was used to detect the differentiation of neurons, astrocytes and microglia in the hippocampus. Results Compared with the C57+Sal group, the C57+ Al(OH)3 group showed no significant changes in total distance, total center time and segmental distance in the open field test, as well as no significant changes in open arm time percentage in the elevated plus maze test and the percentage of dark box time in the light-dark box test. In the three-box socialization test, the C57+ Al(OH)3 group showed no difference in chamber time, a preference for unfamiliar objects in both chamber preference index and sniffing preference index (P < 0.05), and significantly higher grooming time than the control group (P < 0.05); The results of novel object recognition test and Y-maze test showed the C57+Al(OH)3 group had a significantly lower novel object recognition index and spontaneous alternation exploration behavior ratio than those in the control group (P < 0.05); In the morris water maze test, the C57+Al(OH)3 group had a significantly lower target quadrant time than those in the control group (P < 0.05). Compared with the C57+Sal group, the C57+Al(OH)3 group had a significantly reduced number of neural stem cells in the hippocampal dentate gyrus (P < 0.05), thinner granule layer thickness (P < 0.01) and increased differentiation of mature astrocytes (P < 0.05). Conclusion Neonatal Al(OH)3 exposure can lead to social and cognitive dysfunction in adult mice, which may be related to hippocampal developmental defects.

Objective To investigate the effects of naringin (Nar) on lipopolysaccharide (LPS)-induced depression-like behaviors in mice. Methods Thirty C57BL/6 male mice (8 weeks old, SPF grade, weighting 20~23 g) were randomly divided into 3 groups (n=10): control group, saline (Sal)+LPS group, and Nar+LPS group. The mice of the last group were pretreated with Nar (80 mg/kg, i.p., once a day for 8 consecutive days). The exploratory behavior and anxiety-like behavior in mice were assessed by open field test, light and dark box experiment and elevated plus maze test. Sugar water preference test, hanging tail test and forced swimming test were used to evaluate the depression-like behaviors of the mice. Immunohistochemical assay for Iba1 was adopted to detect the effects of Nar and LPS treatments on the number of microglia in the hippocampus of mice. Western blotting and qRT-PCR were performed to determine the protein expression of NF-κB and the mRNA levels of IL-1β, TNF-α and NF-κB in mouse hippocampus, respectively. Results As compared with the control group, the mice in the Sal+LPS group showed decreased preference for sugar water (P < 0.05), and increased immobile time in the forced swimming test (P < 0.01) as well as in the hanging tail test (P < 0.05). The number of microglia in the hippocampus was elevated (P < 0.01), the protein level of NF-κB and the mRNA levels of IL-1β, TNF-α and NF-κB were also up-regulated (P < 0.05). When compared with the Sal+LPS group, the mice in the Nar+LPS group presented increased preference for sugar water (P < 0.01), and decreased immobility time in the forced swimming test (P < 0.01) and hanging tail test (P < 0.05), with higher number of microglia in the hippocampus (P < 0.01), and lower protein levels of NF-κB and mRNA levels of IL-1β, TNF-α and NF-κB (P < 0.01). Conclusion Nar may ameliorate LPS-induced depression-like behaviors in mice by inhibiting inflammation in the hippocampus.

In the past 5 years, the MOOC-based teaching method has been extensively applied as an experimental educational method in medical education in China. However, the effects of this teaching method on medical education are still controversial and ambiguous. To assess the effectiveness of the MOOC-based teaching method in medical education in China, we conducted the meta-analysis. Literature search was performed through the PubMed, Embase, Web of Knowledge and CNKI databases through March 3, 2020. Studies evaluating the effectiveness of the MOOC-based teaching method in medical education in China were included in our meta-analysis. All data were pooled using a fixed- or random-effect model based on a heterogeneity test. Hedges' g was calculated to evaluate the effectiveness of the MOOC-based teaching method on the final exam knowledge scores of participants. Subgroup analyses were also carried out. There were 27 studies (25 records) identified in our meta-analysis. The final exam knowledge scores of participants were statistically higher in the MOOC group compared with the controls in medical courses in China (Hedges' g = 1.080, 95%CI 0.592-1.567, p < 0.001). Obvious heterogeneity across studies was found in the study. Further analysis demonstrated that a significant difference in favor of the MOOC-based teaching method compared with the traditional teaching method in medical students and doctors. The MOOC-based teaching method may be applicable to medical education in China, strengthening the roles of MOOCs in medical education.

Objective To investigate the effects of Chaihu Oral Liquid (CHOL) on the neurogenesis in hippocampal dentate gyrus (DG) and short-term memory defects in BTBR T+ Itpr3tf/J (BTBR) autism model mice. Methods Healthy adult male C57BL/6J(C57) mice (7~8 weeks old, 24.72±1.35 g) and BTBR mice (7~ 8 weeks old, 27.7±1.42 g) were randomly divided into groups as follows (n=4 in each group): C57 control, C57 drug treatment, BTBR control, and BTBR drug treatment. Mice in the treatment groups were given CHOL solution gavage (10 μL/g) once a day for 7 consecutive days, while those of the control group received equal volume of normal saline. Daily changes of body weight were recorded. After the last administration, hair grooming, bead embedding, new object recognition and open field experiments were conducted on the next day and lasted for 4 d. Finally, the samples of mice brain tissue were harvested, and immunofluorescence staining was performed to detect the NeuN, DCX, SOX2/GFAP labeled nerve cells in hippocampal DG. Results Behavioral results suggested that mice in the BTBR control group showed a more obvious preference for old objects in the new object recognition experiment (P < 0.01), as compared with the C57 control group, while the new object recognition index was significantly improved in the BTBR drug treatment group (P < 0.05). Moreover, the BTBR control group presented more repetitive behavior and longer movement distance than the C57 control during the hair grooming, bead embedding and open field experiments, as well as higher body weight (P < 0.05), whereas the BTBR treatment group had no significant changes in comparison with the BTBR control regarding these aspects. There were no notable differences between the C57 control and C57 treatment groups in terms of new object recognition index, repetitive behavior, motor ability and body weight. Immunofluorescence staining results indicated that the numbers of NeuN labeled mature neurons and DCX labeled newborn neurons in hippocampal DG were greatly decreased in the BTBR control group, so as the number of SOX/GFAP labeled neural progenitor cells (P < 0.01), while the number of neurocytes was remarkably increased in the BTBR drug treatment group (P < 0.05). There were no significant differences in the numbers of NeuN, DCX and SOX2/GFAP labeled neurocytes between the C57 control and the C57 treatment groups. Conclusion CHOL promotes the generation of hippocampal DG nerve progenitor cells, new and mature neurons in adult BTBR mice, and improves the short-term learning and memory dysfunction.

Objective To investigate the effects of specific liver X receptor β (LXRβ) knockout in astrocytes on early postnatal hippocampal neurogenesis in mice. Methods Cre/loxP system was used to construct a mouse model with specific LXRβ knockout in astrocyte. Then the mice were divided into control group (LXRβfl/fl, n=3) and astrocyte specific LXRβ knockout group (LXRβ cKOGFAP, n=3). On postnatal day 7 (P7), both groups were intraperitoneally injected with 5-Bromo-2'-deoxyuridine (BrdU), and the brain samples of mice were collected 2 h after drug administration. HE staining was performed on brain samples of the P2 and P7 mice to compare the changes of hippocampal structure between the 2 groups. The expression levels of BrdU, SOX2/GFAP, NeuN and Prox1 in the hippocampal dentate gyrus (DG) were detected in the P7 mice by immunofluorescence staining, so as the levels of NeuN and Prox1 in the P14 mice. Results HE staining showed no great changes in the structure and area of hippocampal DG between the LXRβfl/fl and LXRβ cKOGFAP groups at P2 and P7. For the P7 mice, the LXRβ cKOGFAP group had larger number of BrdU-labeled positive cells in DG of the hippocampus (P < 0.05), while less numbers of Sox2-labeled neural precursor cells (P < 0.01) and SOX2/GFAP co-labeled radial glial cells (RGCs) (P < 0.05) in DG layer as compared with the LXRβfl/fl group. There was no statistical significance in the expression of immature neuron marker Prox1 and mature neuron marker NeuN between the 2 groups. At P14, the expression of NeuN in the DG of LXRβ cKOGFAP mice was remarkably reduced (P < 0.05), whilse the level of Prox1 between the 2 groups was not significant. Conclusion Specific knockout of LXRβ in astrocytes inhibits early postnatal neurogenesis of hippocampal DG in mice.

Objective To determine the effects of simulated altitude hypoxia conditions on anxiety- and depression-like behaviors in mice. Methods C57 adult male mice were divided into 3 groups (n=10): plain control group, 24 h plateau hypoxia group, and 7 d plateau hypoxia group. Behavioral observations were used to detect anxiety-like behaviors, short-term memory, and depression-like behaviors in the mice. Immunohistochemical assay was applied to measure the number of C-Fos, AVP and GR immunoreactive cells in the paraventricular nucleus of the hypothalamus. Enzyme linked immunosorbent assay (ELISA) was adopted to detect the concentrations of adrenocorticotropic hormone (ACTH) and corticosterone in the blood. Results The Results of the elevated plus maze test showed that the mice in the 7 d plateau hypoxia group had a lower percentage of open arm time and increased anxiety-like behavior than those of the control group. Tail suspension test indicated that the mice of the 7 d plateau hypoxia group had more immobile time and increased depression-like behavior than those of the control group (P < 0.01). In the forced swimming test, the 24 h hypoxia group had significantly longer immobility time and increased depression-like behavior than the control group (P < 0.05). Immunohistochemical assay showed that the C-Fos protein in the paraventricular nucleus of the hypothalamus was significantly activated in the 7-d plateau hypoxia group. The numbers of AVP and GR positive neurons were increased in the paraventricular nucleus of the hypothalamus in the 7 d plateau hypoxia group (P < 0.01). Compared with the control group, the ACTH concentration of mice was elevated in the 7 d plateau hypoxia group (P < 0.05), so was the corticosterone concentration in the mice in the 24 h plateau hypoxia group (P < 0.05). Conclusion Rapidly entering the high altitude can cause anxiety- and depression-like behaviors in mice, and the stress responses are regulated by the hypothalamic-pituitary-adrenal axis.

Objective To investigate the effects of metformin (MET) treatment during early postnatal period on hippocampal neurogenesis of neonatal BTBR T+Itpr3tf/J (BTBR) mouse model of autism. Methods Healthy C57BL/6J (C57) and BTBR male pups were randomly divided into C57 normal saline group (C57+NS), C57 MET treatment group (C57+MET), BTBR+NS, and BTBR+MET group, with 5 animals in each group. From postnatal day 7 (P7) to P14, MET (200 mg/kg) or normal saline (same volume of sterile saline solution) were intraperitoneally injected into the corresponding mice, once per day. In 2 h after the last injection on P14, all mice were sacrificed, and the brains were collected and sliced coronally. Fluorescent immunostaining was performed to detect the expression of 5-bromo-2'-deoxyuridine (BrdU), Ki67, Sox2/GFAP and Prox1 in the dentate gyrus (DG). Results On P14, the numbers of BrdU-labeled cells and Ki67-labeled cells were significantly less in the DG of BTBR+NS group than the C57+NS group (P < 0.05), while the numbers were obviously increased in BTBR+MET group than the C57+MET group (P < 0.05). Although there were remarkably less Sox2 and GFAP double-positive cells (neural stem cells) and Prox1-positive cells (newborn neurons) in BTBR+NS group than the C57+NS group (P < 0.05), the 2 kinds of cells were increased obviously in BTBR+MET group than the BTBR+NS group (P < 0.05). However, MET treatment showed no effect on the hippocampal neurons, and there were no significant differences in the numbers of BrdU-, Ki67-, Sox2/GFAP- and Prox1-labeled cells between the C57+MET and C57+NS groups. Conclusion MET treatment in early postnatal period significantly improves the defects of hippocampal neurogenesis, and promotes the proliferation of hippocampal DG neurons and neural stem cells in BTBR mice.

Retinal degeneration (RD), a group of diseases leading to irreversible vision loss, is characterised by retinal pigment epithelium (RPE) or retinal neuron damage and loss. With fewer risks of immune rejection and tumorigenesis, stem cell‐secreted extracellular vesicles (EVs) offer a new cell‐free therapeutic paradigm for RD, which remains to be investigated. Human retinal organoid‐derived retinal progenitor cells (hERO‐RPCs) are an easily accessible and advanced cell source for RD treatment. However, hERO‐RPCs‐derived EVs require further characterisation. Here, we compared the characteristics of EVs from hERO‐RPCs (hRPC‐EVs) with those of human embryonic stem cell (hESC)‐derived EVs (hESC‐EVs) as controls. Based on in‐depth proteomic analysis, we revealed remarkable differences between hRPC‐EVs and hESC‐EVs. A comparison between EVs and their respective cells of origin demonstrated that the protein loading of hRPC‐EVs was more selective than that of hESC‐EVs. In particular, hESC‐EVs were enriched with proteins related to angiogenesis and cell cycle, whereas hRPC‐EVs were enriched with proteins associated with immune modulation and retinal development. More importantly, compared with that of hESC‐EVs, hRPC‐EVs exhibited a lower correlation with cell proliferation and a unique capacity to regulate lipid metabolism. It was further confirmed that hRPC‐EVs potentially eliminated lipid deposits, inhibited lipotoxicity and oxidative stress, and enhanced phagocytosis and survival of oleic acid‐treated ARPE‐19 cells. Mechanistically, hRPC‐EVs are integrated into the mitochondrial network of oleic acid‐treated ARPE‐19 cells, and increased the level of mitochondrial fatty acid β‐oxidation‐related proteins. Thus, organoid‐derived hRPC‐EVs represent a promising source of cell‐free therapy for RD, especially for blinding diseases related to abnormal lipid metabolism in RPE cells. [ABSTRACT FROM AUTHOR]

Objective To explore the therapeutic effect of estrogen receptor β agonist ly3201 on autism-like behaviors in BTBR mice. Methods Healthy neonatal (2 days old) C57BL/6J(C57) and BTBR littermate mice were both divided into 2 groups and subjected to intraperitoneal injections of estrogen receptor β agonist ly3201 at the dose of 1.6 mg/kg or normal saline of an equivalent volume. We measured the expression levels of estrogen receptor β in the cerebral cortex and hippocampus of the mice on day 14 after birth with immunohistochemistry and real-time PCR, and tested the mice for autism-like behaviors at 2 months of age. Results At 14 d after birth, the expression levels of estrogen receptor β in the cerebral cortex and hippocampus were significantly lower in BTBR mice than in C57 mice (P < 0.05), and treatment with ly3201 obviously enhanced estrogen receptor β expression in both BTBR and C57 mice (P < 0.01). In the three-chambered social test, BTBR mice with ly3201 treatment spent significantly longer time in the chamber with other mice than in the chamber with a new object (P < 0.05); they also spent significantly longer time for exploratory sniffing of other mice than of the new object (P < 0.05). In the male-female reciprocal social interaction test, compared with the saline-treated mice, BTBR mice with ly3201 treatment exhibited longer time of nose-to-nose sniffing (P < 0.05) and anogenital sniffing (P < 0.05) with a significantly reduced time for cage exploration (P < 0.05). Conclusion Estrogen receptor β agonist ly3201 activates the expression of endogenous estrogen receptor in the hippocampus and cortex to alleviate social deficits in BTBR mice.

The presynaptic release apparatus can be specialized to enable specific synaptic functions. Habituation is the diminishing of a physiological response to a frequently repeated stimulus and in Aplysia, habituation to touch is mediated by a decrease in transmitter release from the sensory neurons that respond to touch even after modest rates of action potential firing. This synaptic depression is not common among Aplysia synaptic connections suggesting the presence of a release apparatus specialized for this depression. We found that specific splice forms of ApCaV2, the calcium channel required for transmitter release, are preferentially used in sensory neurons, consistent with a specialized release apparatus. However, we were not able to find a specific ApCaV2 splice uniquely required for synaptic depression. The C-terminus of ApCaV2 alpha1 subunit retains conserved binding to Aplysia rab-3 interacting molecule (ApRIM) and ApRIM-binding protein (ApRBP) and the C-terminus is required for full synaptic expression of ApCaV2. We also identified a splice form of ApRIM that did not interact with the ApCav2 alpha 1 subunit, but it was not preferentially used in sensory neurons. [ABSTRACT FROM AUTHOR]

Retinal organoids (ROs) derived from human pluripotent stem cells (hPSCs) have become a promising model in vitro to recapitulate human retinal development, which can be further employed to explore the mechanisms of retinal diseases. However, the current culture systems for ROs lack physiologically relevant microenvironments, such as controllable mechano-physiological cues and dynamic feedback between cells and the extracellular matrix (ECM), which limits the accurate control of RO development. Therefore, we designed a controllable perfusion microfluidic chip (CPMC) with the advantages of precisely controlling fluidic shear stress (FSS) and oxygen concentration distribution in a human embryonic stem cell (hESC)-derived RO culture system. We found that ROs cultured under this system allow for expanding the retinal progenitor cell (RPC) pool, orchestrating the retinal ganglion cell (RGC) specification, and axon growth without disturbing the spatial and temporal patterning events at the early stage of RO development. Furthermore, RNA sequencing data revealed that the activation of voltage-gated ion channels and the increased expression of ECM components synergistically improve the growth of ROs and facilitate the differentiation of RGCs. This study elaborates on the advantages of the designed CPMC to promote RO growth and provide a controllable and reliable platform for the efficient maturity of RGCs in the ROs, promising applications in modeling RGC-related disorders, drug screening, and cell transplantation. [ABSTRACT FROM AUTHOR]