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Although cigarette smoking is known to be a critical risk factor for various organ systems and cancers, accumulating evidence indicates that nicotine - a main constituent of cigarette smoking - can exert neuroprotective effects on neuronal cells through nicotinic acetylcholine receptors (nAChRs). However, the precise molecular mechanisms for nicotinic neuroprotective actions remain to be fully elucidated. In this study, we examine the effects of agonists, such as nicotine and PNU282987, on tropomyosin-related kinase (Trk)-dependent neuroprotective pathways in PC12 cells overexpressing a Trk neurotrophin receptor (PCtrk cells). We found that even considerably higher concentrations (mM range for nicotine and µM range for PN282987) of nAChR agonists exert favorable effects, such as the augmentation of nerve growth factor (NGF)-induced Trk neurotrophin receptor autophosphorylation of tyrosine residues and NGF-induced neurite extension. Moreover, nicotine upregulated reactive oxygen species (ROS) levels in the cells. ROS production was completely cancelled by pretreatment with Mito-Tempo, a mitochondria-targeted antioxidant, indicating that the main source of ROS production by nicotine was mitochondria. Furthermore, treatment with nAChR agonists appeared to induce autophagic flux, as evidenced by the upregulation of LC3-II expression in cells. Furthermore, sucrose density ultracentrifugation of nicotine-treated cells clearly disclosed the augmented recruitment of α7nAChR protein into the lipid rafts fraction of the membrane. Intriguingly, a pull-down assay of anti-Trk antibody immunoprecipitates clearly included α7nAChR protein, indicating that Trk and α7nAChR proteins form a complex. These results reveal a new molecular interaction between activated α7nAChR and Trk protein that may serve as a new molecular basis of nicotine-induced neuroprotective action., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tatsuro Mutoh reports financial support was provided by the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan. Tatsuro Mutoh reports a relationship with the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan that includes: funding grants. If there are other authors, they 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 B.V. All rights reserved.)

Background: Our previous studies indicated that changes in the functioning of the brain glutamatergic system involving the NMDA receptor may affect cytochrome P450 2D (CYP2D) in the brain. Since CYP2D may contribute to the metabolism of neurotransmitters and neurosteroids engaged in the pathology and pharmacology of neuropsychiatric diseases, in the present work we have investigated the effect of compound LY354740, an agonist of glutamatergic metabotropic receptor mGlu 2/3 , on brain and liver CYP2D., Methods: The activity (high performance liquid chromatography with fluorescence detection) and protein levels (Western blotting) of CYP2D were measured in the microsomes from the liver and different brain areas of male Wistar rats after 5 day-treatment with LY354740 (10 mg/kg ip). The results were analyzed statistically using Student's t-test., Results: Among the investigated brain areas, the highest CYP2D activity was found in the cerebellum and brainstem, which exceeded that in the thalamus, cortex, hippocampus and frontal cortex. The mGlu 2/3 receptor agonist LY354740 administered for five consecutive days significantly increased the protein level and activity of CYP2D in the frontal cortex. Such a tendency was also observed in the other brain areas. LY354740 did not affect the CYP2D activity in the liver., Conclusions: Repeated administration of the mGlu 2/3 receptor agonist, the compound LY354740 specifically increases the protein level and activity of CYP2D in the frontal cortex, which may accelerate dopamine synthesis via an alternative CYP2D-mediated route in the mesocortical dopaminergic pathway, and thus may contribute to the beneficial pharmacological effect on negative symptoms of schizophrenia., Competing Interests: Declarations. Conflict of interest: The authors declare no competing interests., (© 2024. The Author(s).)

Background: Acute liver injury is a disease characterized by severe liver dysfunction, caused by significant infiltration of immune cells and extensive cell death with a high mortality. Previous studies demonstrated that the α7 nicotinic acetylcholine receptor (α7nAChR) played a crucial role in various liver diseases. The hypothesis of this study was that activating α7nAChR could alleviate acute liver injury and investigate its possible mechanisms., Methods: Acute liver injury was induced by intraperitoneal injection of lipopolysaccharide (LPS)/D-galactosamine (D-Gal) in wild type, α7nAChR knockout (α7nAChR-/-) and stimulator of interferon gene (STING) mutation (Stinggt/gt) mice in the presence or absence of a pharmacologic selective α7nAChR agonist (PNU-282987). The effects of α7nAChR on hepatic injury, inflammatory response, mitochondrial damage, necroptosis, and infiltration of immune cells during acute liver injury were assessed., Results: The expression of α7nAChR in liver tissue was increased in LPS/D-Gal-induced acute liver injury mice. Compared to the age-matched wild-type mice, α7nAChR deficiency decreased the survival rate, exacerbated the hepatic injury accompanied with enhanced inflammatory response and oxidative stress, and aggravated hepatic mitochondrial damage and necroptosis. Conversely, pharmacologic activation of α7nAChR by PNU-282987 displayed the opposite trends. Furthermore, PNU-282987 significantly reduced the proportion of infiltrating monocyte-derived macrophages (CD45+CD11bhiF4/80int), M1 macrophages (CD45+CD11b+F4/80+CD86hiCD163low), and Ly6Chi monocytes (CD45+CD11b+MHC [major histocompatibility complex] ⅡlowLy6Chi), but increased the resident Kupffer cells (CD45+CD11bintF4/80hiTIM4hi) in the damaged hepatic tissues caused by LPS/D-Gal. Interestingly, α7nAChR deficiency promoted the STING signaling pathway under LPS/D-Gal stimulation, while PNU-282987 treatment significantly prevented its activation. Finally, it was found that Sting mutation abolished the protective effects against hepatic injury by activating α7nAChR., Conclusions: The authors' study revealed that activating α7nAChR could protect against LPS/D-Gal-induced acute liver injury by inhibiting hepatic inflammation and necroptosis possibly via regulating immune cells infiltration and inhibiting STING signaling pathway., (Copyright © 2024 American Society of Anesthesiologists. All Rights Reserved.)

Consumption of palatable food (PF) can alleviate anxiety, and pain in humans. Contrary, spontaneous withdrawal of long-term PF intake produces anxiogenic-like behavior and abnormal pain sensation, causing challenges to weight-loss diet and anti-obesity agents. Thus, we examined α7-nicotinic acetylcholine receptors (α7nAChR) involvement since it plays essential role in nociception and psychological behaviors., Methods: Adult male C57BL/6 mice were placed on a Standard Chow (SC) alone or with PF on intermittent or continuous regimen for 6 weeks. Then, mice were replaced with normal SC (spontaneous withdrawal). Body weight, food intake, and calories intake with and without the obesogenic diet were measured throughout the study. During PF withdrawal, anxiety-like behaviors and pain sensitivity were measured with PNU-282987 (α7nAChR agonist) administration., Results: Six weeks of SC + PF-intermittent and continuous paradigms produced a significant weight gain. PF withdrawal displayed hyperalgesia and anxiety-like behaviors. During withdrawal, PNU-282987 significantly attenuated hyperalgesia and anxiety-like behaviors., Conclusion: The present study shows that a PF can increase food intake and body weight. Also, enhanced pain sensitivity and anxiety-like behavior were observed during PF withdrawal. α7nAChR activation attenuated anxiolytic-like behavior and hyperalgesia in PF abstinent mice. These data suggest potential therapeutic effects of targeting α7 nAChRs for obesity-withdrawal symptoms in obese subjects., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

The aim of this study was to analyse the essential oil of Lavandula dentata from Algeria and to test the antioxidant and antimicrobial properties of this plant. The essential oil (EO) (57 constituents) included mainly α-pinene, β-pinene, nopinone, linalool, cryptone, and limonene. The plant polyphenolic contents and the antioxidant activity were determined. The antimicrobial effect of the EO and the methanolic extract (ME) was assessed against referenced and clinical bacterial strains, and also foodborne fungal isolates. The EO minimal inhibitory concentration (MIC) values varied from 0.25 to 4 mg/mL and minimal bactericidal concentrations (MBCs) were less than 8 mg/mL except for S. aureus , clinical Klebsiella, S. epidermidis , and B. subtilis . The mould strains were significantly inhibited by the EO (87.50% to 88.33%). The MIC values were 3.60-15.62 mg/mL and 0.5-4 mg/mL for ME and EO, respectively. The minimal fungicidal concentration (MFC) values ranged from 31 to 125 mg/mL and from 2 to 8 mg/mL for ME and EO, respectively.

Co-administration of mirogabalin besylate and nonsteroidal anti-inflammatory drugs is effective for neuropathic pain; however, mechanism of its action remains unknown. We aimed to evaluate the mechanism of this synergistic effect of the concomitant administration for neuropathic pain using chronic constriction injury model rats. Fifty male Wister rats of 7-week-old were used. Right sciatic nerve ligation was performed in 40 rats and they were sub-divided into four groups: vehicle, mirogabalin, diclofenac sodium and co-administration of them. Ten rats underwent sham surgery. Fluorogold was attached to sciatic nerve during surgery. Von Frey filament and weight bearing tests were performed on postoperative Day 6 as behavioral assessments and drug was administrated intraperitoneally. Half rats in each group underwent behavioral assessment and perfusion fixation using 4% paraformaldehyde on postoperative Day 7 and remaining on postoperative Day 14. Subsequently, dorsal root ganglion at L4 to L6 was collected and examined immunohistochemistry for calcitonin gene-related peptide, and their immunoreactivity in fluorogold-labeled neurons was measured. Spinal cord at lumbar swelling was resected, immunostained for ionized-calcium-binding adapter molecule-1 and glial fibrillary acidic protein, and immunoreactive neurons in dorsal horn of spinal cords were calculated as the occupancy of them. Mirogabalin suppresses the neuropeptide-release from presynaptic afferent neuron directly and it resulted in suppressing glia cells activation. Diclofenac sodium inhibits cyclooxygenase-2 and prostaglandin production, related to allodynia. These effects of mirogabalin and diclofenac sodium, respectively, inhibited glia cells strongly, which is presumed to be one of the mechanisms for the effectiveness of their co-administration for neuropathic pain., (© 2024 Orthopaedic Research Society.)

Background: Neonatal necrotizing enterocolitis (NEC) is one of the most prevalent and severe intestinal emergencies in newborns. The inflammatory activation of macrophages is associated with the intestinal injury of NEC. The neuroimmune regulation mediated by α7 nicotinic acetylcholine receptor (α7nAChR) plays an important role in regulating macrophage activation and inflammation progression, but in NEC remains unclear. This study aims to explore the effect of macrophage α7nAChR on NEC., Methods: Mice NEC model were conducted with high-osmolarity formula feeding, hypoxia, and cold stimulation. The α7nAChR agonist PNU-282987 and mTOR inhibitor rapamycin were treated by intraperitoneal injections in mice. The expression and distribution of macrophages, α7nAChR, and phospho-mammalian target of rapamycin (p-mTOR) in the intestines of NEC patients and mice was assessed using immunohistochemistry, immunofluorescence, and flow cytometry. The expression of NLRP3, activated caspase-1 and IL-1β in mice intestines was detected by flow cytometry, western blot or ELISA. In vitro, the mouse RAW264.7 macrophage cell line was also cultured followed by various treatments. Expression of p-mTOR, NLRP3, activated caspase-1, and IL-1β in macrophages was determined., Results: Macrophages accumulated in the intestines and the expression of α7nAChR in the mucosal and submucosal layers of the intestines was increased in both the NEC patients and mice. The p-mTOR and CD68 were increased and co-localized in intestines of NEC patients. In vitro, α7nAChR agonist PNU-282987 significantly reduced the increase of NLRP3, activated caspase-1, and IL-1β in macrophages. PNU-282987 also significantly reduced the increase of p-mTOR. The effect was blocked by AMPK inhibitor compound C. The expression of NLRP3, activated caspase-1, and IL-1β was inhibited after mTOR inhibitor rapamycin treatment. In NEC model mice, PNU-282987 reduced the expression of p-mTOR, NLRP3, activated caspase-1, and IL-1β in the intestine. Meanwhile, rapamycin significantly attenuated NLRP3 activation and the release of IL-1β. Moreover, the proportion of intestinal macrophages and intestinal injury decreased after PNU-282987 treatment., Conclusion: Macrophage α7nAChR activation mitigates NLRP3 inflammasome activation by modulating mTOR phosphorylation, and subsequently alleviates intestinal inflammation and injury in NEC., 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.)

There are presently no acknowledged therapeutic targets or official drugs for the treatment of muscle fatigue. The alpha7 nicotinic acetylcholine receptor (α7nAChR) is expressed in skeletal muscle, with an unknown role in muscle endurance. Here, we try to explore whether α7nAChR could act as a potential therapeutic target for the treatment of muscle fatigue. Results showed that nicotine and PNU-282987 (PNU), as nonspecific and specific agonists of α7nAChR, respectively, could both significantly increase C57BL6/J mice treadmill-running time in a time- and dose-dependent manner. The improvement effect of PNU on running time and ex vivo muscle fatigue index disappeared when α7nAChR deletion. RNA sequencing revealed that the differential mRNAs affected by PNU were enriched in glycolysis/gluconeogenesis signaling pathways. Further studies found that PNU treatment significantly elevates glycogen content and ATP level in the muscle tissues of α7nAChR +/+ mice but not α7nAChR -/- mice. α7nAChR activation specifically increased endogenous glycogen-targeting protein orosomucoid (ORM) expression both in vivo skeletal muscle tissues and in vitro C2C12 skeletal muscle cells. In ORM1 deficient mice, the positive effects of PNU on running time, glycogen and ATP content, as well as muscle fatigue index, were abolished. Therefore, the activation of α7nAChR could enhance muscle endurance via elevating endogenous anti-fatigue protein ORM and might act as a promising therapeutic strategy for the treatment of muscle fatigue., (© 2024 Wiley Periodicals LLC.)

Purpose of Review: Mirogabalin is a novel gabapentinoid medication for the treatment of neuropathic pain. The purpose of this review is to discuss current evidence for its use. Gabapentinoids are widely prescribed for neuropathic pain. Mirogabalin offers theoretical advantages over traditional gabapentinoids due to its specificity for the α2δ-1 subunit of voltage-gated calcium channels. It is theorised that this specificity may reduce adverse drug reactions by minimising binding to the α2δ-2 subunit which is responsible for many of the gabapentinoid side effects., Recent Findings: Mirogabalin's slower dissociation from the α2δ-1 compared with α2δ-2, and its higher potency may also impart an efficacy benefit over traditional gabapentinoids. These theoretical advantages of mirogabalin remain inconclusive in clinical practice, with mixed evidence regarding mirogabalin versus traditional gabapentinoids. Some studies suggest a reduced side effect profile yet, others fail to demonstrate significant differences. Regarding efficacy, mirogabalin may be superior to placebo for several neuropathic pain syndromes, but evidence of widespread benefit over traditional gabapentinoids is currently lacking., Summary: Mirogabalin offers theoretical promise, but large, independent studies are required to further assess its performance versus traditional gabapentinoids., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

We investigated the impact of the human-specific gene CHRFAM7A on the function of α7 nicotinic acetylcholine receptors (α7 nAChRs) in two different types of neurons: human-induced pluripotent stem cell (hiPSC)-derived cortical neurons, and superior cervical ganglion (SCG) neurons, taken from transgenic mice expressing CHRFAM7A. dupα7, the gene product of CHRFAM7A, which lacks a major part of the extracellular N-terminal ligand-binding domain, co-assembles with α7, the gene product of CHRNA7. We assessed the receptor function in hiPSC-derived cortical and SCG neurons with Fura-2 calcium imaging and three different α7-specific ligands: PNU282987, choline, and 4BP-TQS. Given the short-lived open state of α7 receptors, we combined the two orthosteric agonists PNU282987 and choline with the type-2 positive allosteric modulator (PAM II) PNU120596. In line with different cellular models used previously, we demonstrate that CHRFAM7A has a major impact on nicotinic α7 nAChRs by reducing calcium transients in response to all three agonists., (© 2024 The Author(s). European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Alzheimer's disease (AD) is an age-dependent incurable neurodegenerative disorder accompanied by neuroinflammation, amyloid accumulation, and memory impairment. It begins decades before the first clinical symptoms appear, and identifying early biomarkers is key for developing disease-modifying therapies. We show now in a mouse model of AD that before any amyloid deposition the brains of 1.5-month-old mice contain increased levels of pro-inflammatory cytokines IL-1β and IL-6, decreased levels of nicotinic acetylcholine receptors (nAChRs) in the brain and brain mitochondria and increased amounts of α7 nAChR-bound Aβ 1-42 , along with impaired episodic memory and increased risk of apoptosis. Both acute (1-week-long) and chronic (4-month-long) treatments with α7-selective agonist PNU282987, starting at 1.5 months of age, were well tolerated. The acute treatment did not affect the levels of soluble Aβ 1-42 but consistently upregulated the α7 nAChR expression, decreased the level of α7-Aβ 1-42 complexes, and improved episodic memory of 1.5-month-old mice. The chronic treatment, covering the disease development phase, strongly upregulated the expression of all abundant brain nAChRs, reduced both free and α7-coupled Aβ 1-42 within the brain, had anti-inflammatory and antiapoptotic effects, and potently upregulated cognition, thus identifying α7 nAChRs as both early biomarker and potent therapeutic target for fighting this devastating disease., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Olga Garaschuk, Maryna Skok reports financial support was provided by Alexander von Humboldt Foundation. If there are other authors, they 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 Masson SAS.. All rights reserved.)

Chronic diabetes mellitus compromises the vascular system, which causes organ injury, including in the lung. Due to the strong compensatory ability of the lung, patients always exhibit subclinical symptoms. Once sepsis occurs, the degree of lung injury is more severe under hyperglycemic conditions. The α7 nicotinic acetylcholine receptor (α7nAChR) plays an important role in regulating inflammation and metabolism and can improve endothelial progenitor cell (EPC) functions. In the present study, lung injury caused by sepsis was compared between diabetic rats and normal rats. We also examined whether α7nAChR activation combined with EPC transplantation could ameliorate lung injury in diabetic sepsis rats. A type 2 diabetic model was induced in rats via a high-fat diet and streptozotocin. Then, a rat model of septic lung injury was established by intraperitoneal injection combined with endotracheal instillation of LPS. The oxygenation indices, wet-to-dry ratios, and histopathological scores of the lungs were tested after PNU282987 treatment and EPC transplantation. IL-6, IL-8, TNF-α, and IL-10 levels were measured. Caspase-3, Bax, Bcl-2, and phosphorylated NF-κB (p-NF-κB) levels were determined by blotting. Sepsis causes obvious lung injury, which is exacerbated by diabetic conditions. α7nAChR activation and endothelial progenitor cell transplantation reduced lung injury in diabetic sepsis rats, alleviating inflammation and decreasing apoptosis. This treatment was more effective when PNU282987 and endothelial progenitor cells were administered together. p-NF-κB levels decreased following treatment with PNU282987 and EPCs. In conclusion, α7nAChR activation combined with EPC transplantation can alleviate lung injury in diabetic sepsis rats through the NF-κB signaling pathway., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Herpes simplex virus type 1 (HSV-1), a neurotropic DNA virus, establishes latency in neural tissues, with reactivation causing severe consequences like encephalitis. Emerging evidence links HSV-1 infection to chronic neuroinflammation and neurodegenerative diseases. Microglia, the central nervous system's (CNS) immune sentinels, express diverse receptors, including α7 nicotinic acetylcholine receptors (α7 nAChRs), critical for immune regulation. Recent studies suggest α7 nAChR activation protects against viral infections. Here, we show that α7 nAChR agonists, choline and PNU-282987, significantly inhibit HSV-1 replication in microglial BV2 cells. Notably, this inhibition is independent of the traditional ionotropic nAChR signaling pathway. mRNA profiling revealed that choline stimulates the expression of antiviral factors, IL-1β and Nos2, and down-regulates the apoptosis genes and type A Lamins in BV2 cells. These findings suggest a novel mechanism by which microglial α7 nAChRs restrict viral infections by regulating innate immune responses., 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., (Published by Elsevier B.V.)

GC/MS analysis of Murraya koenigii (L.) Spreng. and Murraya paniculata (L.) Jacq. leaves revealed the identification of 73 components, with an evident greater contribution of monoterpenes hydrocarbons to their total volatiles. α-Pinene (37.5%) and β-caryophyllene (27.4%) were the most abundant compounds in M. koenigii leaves and β-phellandrene (40.7%) in M. paniculata leaves, using headspace. β-Phellandrene (33.7%) was the major constituent by M. koenigii leaves where germacrene D (23.8%), and δ-elemene (22.0%) were predominant in M. paniculata leaves, using steam distillation. M. koenigii leaves oil showed quite remarkable cholinesterase inhibitory activity, where oil of M. paniculata leaves showed strong inhibitory activity against AChE (IC 50 =13.2 ± 0.9 µg/mL) and BChE (IC 50 =5.1 ± 0.3 µg/mL). Germacrene D, α-zingiberene, and δ-elemene showed higher affinity to BChE than AChE as revealed from docking scores (S = -5.65 to -6.03 Kcal/mol) for BChE and (S = -5.56 to -6.25 Kcal/mol) for AChE.

Pulmonary emphysema is a primary component of chronic obstructive pulmonary disease (COPD), a life-threatening disorder characterized by lung inflammation and restricted airflow, primarily resulting from the destruction of small airways and alveolar walls. Cumulative evidence suggests that nicotinic receptors, especially the α7 subtype (α7nAChR), is required for anti-inflammatory cholinergic responses. We postulated that the stimulation of α7nAChR could offer therapeutic benefits in the context of pulmonary emphysema. To investigate this, we assessed the potential protective effects of PNU-282987, a selective α7nAChR agonist, using an experimental emphysema model. Male mice (C57BL/6) were submitted to a nasal instillation of porcine pancreatic elastase (PPE) (50 µl, 0.667 IU) to induce emphysema. Treatment with PNU-282987 (2.0 mg/kg, ip) was performed pre and post-emphysema induction by measuring anti-inflammatory effects (inflammatory cells, cytokines) as well as anti-remodeling and anti-oxidant effects. Elastase-induced emphysema led to an increase in the number of α7nAChR-positive cells in the lungs. Notably, both groups treated with PNU-282987 (prior to and following emphysema induction) exhibited a significant decrease in the number of α7nAChR-positive cells. Furthermore, both groups treated with PNU-282987 demonstrated decreased levels of macrophages, IL-6, IL-1β, collagen, and elastic fiber deposition. Additionally, both groups exhibited reduced STAT3 phosphorylation and lower levels of SOCS3. Of particular note, in the post-treated group, PNU-282987 successfully attenuated alveolar enlargement, decreased IL-17 and TNF-α levels, and reduced the recruitment of polymorphonuclear cells to the lung parenchyma. Significantly, it is worth noting that MLA, an antagonist of α7nAChR, counteracted the protective effects of PNU-282987 in relation to certain crucial inflammatory parameters. In summary, these findings unequivocally demonstrate the protective abilities of α7nAChR against elastase-induced emphysema, strongly supporting α7nAChR as a pivotal therapeutic target for ameliorating pulmonary emphysema., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

LY-404,039 is an orthosteric agonist at metabotropic glutamate 2 and 3 (mGlu 2/3 ) receptors, with a possible additional agonist effect at dopamine D 2 receptors. LY-404,039 and its pro-drug, LY-2140023, have previously been tested in clinical trials for psychiatric indications and could therefore be repurposed if they were shown to be efficacious in other conditions. We have recently demonstrated that the mGlu 2/3 orthosteric agonist LY-354,740 alleviated L-3,4-dihydroxyphenylalanine (L-DOPA)-induced abnormal involuntary movements (AIMs) in the 6-hydroxydopamine (6-OHDA)-lesioned rat without hampering the anti-parkinsonian action of L-DOPA. Here, we seek to take advantage of a possible additional D 2 -agonist effect of LY-404,039 and see if an anti-parkinsonian benefit might be achieved in addition to the antidyskinetic effect of mGlu 2/3 activation. To this end, we have administered LY-404,039 (vehicle, 0.1, 1 and 10 mg/kg) to 6-OHDA-lesioned rats, after which the severity of axial, limbs and oro-lingual (ALO) AIMs was assessed. The addition of LY-404,039 10 mg/kg to L-DOPA resulted in a significant reduction of ALO AIMs over 60-100 min (54%, P  < 0.05). In addition, LY-404,039 significantly enhanced the antiparkinsonian effect of L-DOPA, assessed through the cylinder test (76%, P  < 0.01). These results provide further evidence that mGlu 2/3 orthosteric stimulation may alleviate dyskinesia in PD and, in the specific case of LY-404,039, a possible D 2 -agonist effect might also make it attractive to address motor fluctuations. Because LY-404,039 and its pro-drug have been administered to humans, they could possibly be advanced to Phase IIa trials rapidly for the treatment of motor complications in PD., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Diabetic peripheral neuropathic pain (DPNP) and postherpetic neuralgia (PHN) are challenging and often intractable complex medical conditions, with a substantial impact on the quality of life. Mirogabalin, a novel voltage-gated Ca 2+ channel α2δ ligand, was approved for the indication of DPNP and PHN. However, the time course of effects has not yet been clarified.We aimed to establish pharmacodynamic and placebo effect models of mirogabalin and pregabalin in DPNP and PHN, and to quantitatively compare the efficacy characteristics (maximum efficacy, onset time, and other pharmacodynamic parameters) and safety of mirogabalin and pregabalin. Public databases were comprehensively searched for randomized placebo-controlled clinical trials. A model-based meta-analysis (MBMA) was developed to describe the time course of drug efficacy and placebo effects. Adverse events were compared using a fixed-effects meta-analysis. Sixteen studies including 5,147 participants were eligible for this study. The placebo effect was relatively high and gradually increased with time, and it required at least eight weeks to reach a plateau. The pharmacodynamic model revealed that the maximum pure efficacy for mirogabalin and pregabalin was approximately -7.85 % and -8.86 %, respectively; the efficacy of mirogabalin to relieve DPNP and PHN was not superior to that of pregabalin, and both drugs had similar safety. While the rate constant of the onset rate of pregabalin was approximately thrice as high as that of mirogabalin. In addition, the baseline level of pain was an important factor affecting pregabalin efficacy. These findings are helpful in evaluating the clinical extension value of mirogabalin. They suggest that the high placebo effect and the baseline level of pain should be considered when grouping patients in future research and development of voltage-gated Ca 2+ channel neuroanalgesic., Competing Interests: Declaration of competing interest None, (Copyright © 2024. Published by Elsevier B.V.)

St. John's wort (SJW) extract, a herbal medicine with antidepressant effects, is a potent inducer of intestinal and/or hepatic cytochrome P450 (CYP) enzymes and P-glycoprotein (P-gp), which can cause clinically relevant drug interactions. It is currently not known whether SJW can also induce P-gp activity at the human blood-brain barrier (BBB), which may potentially lead to decreased brain exposure and efficacy of certain central nervous system (CNS)-targeted P-gp substrate drugs. In this study, we used a combination of positron emission tomography (PET) imaging and cocktail phenotyping to gain a comprehensive picture on the effect of SJW on central and peripheral P-gp and CYP activities. Before and after treatment of healthy volunteers (n = 10) with SJW extract with a high hyperforin content (3-6%) for 12-19 days (1800 mg/day), the activity of P-gp at the BBB was assessed by means of PET imaging with the P-gp substrate [ 11 C]metoclopramide and the activity of peripheral P-gp and CYPs was assessed by administering a low-dose phenotyping cocktail (caffeine, omeprazole, dextromethorphan, and midazolam or fexofenadine). SJW significantly increased peripheral P-gp, CYP3A, and CYP2C19 activity. Conversely, no significant changes in the peripheral metabolism, brain distribution, and P-gp-mediated efflux of [ 11 C]metoclopramide across the BBB were observed following the treatment with SJW extract. Our data suggest that SJW does not lead to significant P-gp induction at the human BBB despite its ability to induce peripheral P-gp and CYPs. Simultaneous intake of SJW with CNS-targeted P-gp substrate drugs is not expected to lead to P-gp-mediated drug interactions at the BBB., (© 2024 The Authors. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Both autonomic nervous system dysfunction and immune system activation are characteristic of chronic pain after limb injuries. Cholinergic agonists reduce immune system activation in many settings. We hypothesized, therefore, that alpha-7 nicotinic acetylcholine receptor (α7nAChR) agonist administration would reduce nociceptive and immune changes after tibia fracture and cast immobilization in mice. Fracture mice were treated with either vehicle, a low (.2 mg/kg) dose, or a high (1 mg/kg) dose of the selective α7nAChR agonist PNU-282987 for 4 weeks. We assessed hindpaw allodynia and weight bearing as behavioral outcomes. The assessment of adaptive immune responses included regional lymph node hypertrophy, germinal center formation, α7nAChR expression, and IgM deposition. Assessment of innate immune system activation focused on IL-1β and IL-6 generation in fractured hindlimb skin. We observed that mechanical allodynia and unweighting were alleviated by PNU-282987 treatment. Drug treatment also reduced popliteal lymph node hypertrophy and germinal center formation. Immunohistochemical studies localized α7nAChR to germinal center B lymphocytes, and this expression increased after fracture. Analysis of fracture limb hindpaw skin demonstrated increased inflammatory mediator (IL-1β and IL-6) levels and IgM deposition, which were abrogated by PNU-282987. Serum analyses demonstrated fracture-induced IgM reactivity against keratin 16, histone 3.2, GFAP, and NMDAR-2B. Administration of PNU-282987 reduced the enhancement of IgM reactivity. Collectively, these data suggest that the α7nAChR is involved in regulating posttraumatic innate and adaptive immune responses and the associated nociceptive sensitization. PERSPECTIVE: These studies evaluate the effects of a selective α7nAChR agonist in a tibial fracture/cast immobilization model of limb pain. Administration of the drug reduced nociceptive and functional changes 4 weeks after injury. These novel findings suggest that well-tolerated α7nAChR agonists may be viable analgesics for chronic pain after limb injuries., (Published by Elsevier Inc.)

mGluR2 receptors are widely expressed in limbic brain regions associated with memory, including the hippocampal formation, retrosplenial and frontal cortices, as well as subcortical regions including the mammillary bodies. mGluR2/3 agonists have been proposed as potential therapeutics for neurological and psychiatric disorders, however, there is still little known about the role of these receptors in cognitive processes, including memory consolidation. To address this, we assessed the effect of the mGluR2/3 agonist, eglumetad, on spatial memory consolidation in both mice and rats. Using the novel place preference paradigm, we found that post-sample injections of eglumetad impaired subsequent spatial discrimination when tested 6 h later. Using the immediate early gene c-fos as a marker of neural activity, we showed that eglumetad injections reduced activity in a network of limbic brain regions including the hippocampus and mammillary bodies. To determine whether the systemic effects could be replicated with more targeted manipulations, we performed post-sample infusions of the mGluR2/3 agonist 2R,4R-APDC into the mammillary bodies. This impaired novelty discrimination on a place preference task and an object-in-place task, again highlighting the role of mGluR2/3 transmission in memory consolidation and demonstrating the crucial involvement of the mammillary bodies in post-encoding processing of spatial information., (© 2024. The Author(s).)

Hyperforin is a phloroglucinol derivative isolated from the medicinal plant Hypericum perforatum (St John's wort, SJW). This lipophilic biomolecule displays antibacterial, pro-apoptotic, antiproliferative, and anti-inflammatory activities. In addition, in vitro and in vivo data showed that hyperforin is a promising molecule with potential applications in neurology and psychiatry. For instance, hyperforin possesses antidepressant properties, impairs the uptake of neurotransmitters, and stimulates the brain derived neurotrophic factor (BDNF)/TrkB neurotrophic signaling pathway, the adult hippocampal neurogenesis, and the brain homeostasis of zinc. In fact, hyperforin is a multi-target biomolecule with a complex neuropharmacological profile. However, one prominent pharmacological feature of hyperforin is its ability to influence the homeostasis of cations such as Ca 2+ , Na + , Zn 2+ , and H + . So far, the pathophysiological relevance of these actions is currently unknown. The main objective of the present work is to provide an overview of the cellular neurobiology of hyperforin, with a special focus on its effects on neuronal membranes and the movement of cations., (© 2023 John Wiley & Sons Ltd.)

Elevated expression of anti-apoptotic proteins, such as Bcl-2 and Mcl-1 contributes to poor prognosis and resistance to current treatment modalities in multiple cancers. Here, we report the design, synthesis and characterization of benzimidazole chalcone and flavonoid scaffold-derived bicyclic compounds targeting both Bcl-2 and Mcl-1 by optimizing the structural differences in the binding sites of both these proteins. Initial docking screen of Bcl-2 and Mcl-1 with pro-apoptotic protein Bim revealed possible hits with optimal binding energies. All the optimized bicyclic compounds were screened for their in vitro cytotoxic activity against two oral cancer cell lines (AW8507 and AW13516) which express high levels of Bcl-2 and Mcl-1. Compound 4d from the benzimidazole chalcone series and compound 6d from the flavonoid series exhibited significant cytotoxic activity (IC 50 7.12 μM and 17.18 μM, respectively) against AW13516 cell line. Time Resolved-Fluorescence Resonance Energy Transfer (TR-FRET) analysis further demonstrated that compound 4d and compound 6d could effectively inhibit the Bcl-2 and Mcl-1 proteins by displacing their BH3 binding partners. Both compounds exhibited potent activation of canonical pathway of apoptosis evident from appearance of cleaved Caspase-3 and PARP. Further, treatment of oral cancer cells with the inhibitors induced dissociation of the BH3 only protein Bim from Mcl-1 and Bak from Bcl-2 but failed to release Bax from Bcl-xL thereby confirming the nature of compounds as BH3-mimetics selectively targeting Bcl-2 and Mcl-1. Our study thus identifies bicyclic compounds as promising candidates for anti-apoptotic Bcl-2/Mcl-1 dual inhibitors with a potential for further development., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Neuropathic pain is a complex sort of pain that is detrimental to individuals' health, both physically and mentally, but merely a small portion of them could witness pain alleviation. Mirogabalin, by distinctive binding characteristics of voltage-gated calcium channels, has won approval from the Japanese authority as a third member of gabapentinoids in Japan. Our review was aimed at encompassing the bulk of clinical research on mirogabalin, which included clinical trials, special considerations, coadministration studies, case reports, and cost-effectiveness studies., Methods: A review was carried out on a series of platforms, such as PubMed, MEDLINE, and Scopus, up to December 2021 using the keywords as follows: "mirogabalin OR mirogabalin besylate OR Tarlige OR DS-5565" AND "neuropathic pain OR Neuropathy.", Results: Mirogabalin demonstrated analgesic activity and manageable adverse reactions and provides a new alternative for individuals with PHN or DPNP in 3 phase II and 4 III trials. Mirogabalin alleviated pain markedly in comparison with placebo. Administration of mirogabalin on a long-term basis is a flexible dosage regimen for patients with PHN. It is noteworthy that mirogabalin should be administrated cautiously when combined with probenecid and cimetidine on account of a slight increase in pharmacodynamics effects of mirogabalin., Conclusion: The development of mirogabalin allows further optimization of individual treatment strategies so as to provide more therapeutic choices in this medical domain., Competing Interests: No conflict of interest is involved in this study., (Copyright © 2023 Hui Tang et al.)

Currently, there is a lack of treatments for retinal neurotrauma. To address this issue, this study uses an alpha7 nAChR agonist, PNU-282987, to determine it effects on functional activity in the retina shortly after a traumatic blast exposure. The objectives of this research include: (1) examination of the cellular and functional damage associated with ocular blast exposure, and (2) evaluation of structural and functional changes that occur post PNU-282987 treatment. Significant ocular blast damage was induced in adult mice after exposure to a single blast of 35 psi to the left eye. Blast-exposed transgenic mice expressing tdTomato Müller glia were treated daily with eyedrops containing PNU-282987 for 4 weeks following the blast exposure. Antibody staining studies in these transgenic mice was conducted to examine lineage tracing and electroretinograms (ERGs) were obtained to examine functional changes. Blast exposure caused a significant loss of cells in all retinal layers after 4 weeks. Immunohistochemical analysis demonstrated tdTomato-positive labeled photoreceptors and retinal ganglion cells in blast-exposed mice treated with PNU-282987. ERG recordings were taken from control animals, from blast-damaged animals and from animals exposed to blast followed by 4 weeks of PNU-282987 treatment. Scotopic ERG recordings from blast-exposed mice had significantly decreased amplitudes of a-wave, b-wave, oscillatory potentials and flicker frequencies, which were prevented after PNU-282987 treatment. In photopic experiments, the PhNR response was reduced significantly after blast exposure but the decrease was prevented after treatment with PNU-282987. These are the first experiments that demonstrate preservation of retinal function after blast exposure using an alpha7 nAChR agonist., (Copyright © 2022 IBRO. Published by Elsevier Ltd. All rights reserved.)

Acetylcholine (ACh), which activates muscarinic ACh receptors (mAChRs) and nicotinic ACh receptors (nAChRs), enhances airway ciliary beating by increasing the intracellular Ca 2+ concentration ([Ca 2+ ] i ). The mechanisms enhancing airway ciliary beating by nAChRs have remained largely unknown, although those by mAChRs are well understood. In this study, we focused on the effects of α7-nAChRs and voltage-gated Ca 2+ channels (Ca V s) on the airway ciliary beating. The activities of ciliary beating were assessed by frequency (CBF, ciliary beat frequency) and amplitude (CBD, ciliary bend distance) measured by high-speed video microscopy. ACh enhanced CBF and CBD by 25% mediated by an [Ca 2+ ] i increase stimulated by mAChRs and α7-nAChRs (a subunit of nAChR) in airway ciliary cells of mice. Experiments using PNU282987 (an agonist of α7-nAChR) and MLA (an inhibitor of α7-nAChR) revealed that CBF and CBD enhanced by α7-nAChR are approximately 50% of those enhanced by ACh. CBF, CBD, and [Ca 2+ ] i enhanced by α7-nAChRs were inhibited by nifedipine, suggesting activation of Ca V s by α7-nAChRs. Experiments using a high K + solution with/without nifedipine (155.5 mM K + ) showed that the activation of Ca V s enhances CBF and CBD via an [Ca 2+ ] i increase. Immunofluorescence and immunoblotting studies demonstrated that Cav1.2 and α7-nAChR are expressed in airway cilia. Moreover, IL-13 stimulated MLA-sensitive increases in CBF and CBD in airway ciliary cells, suggesting an autocrine regulation of ciliary beating by Ca V 1.2/α7-nAChR/ACh. In conclusion, a novel Ca 2+ signalling pathway in airway cilia, Ca V 1.2/α7-nAChR, enhances CBF and CBD and activates mucociliary clearance maintaining healthy airways., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Ethnopharmacological Relevance: Ferula hermonis is a small shrub renowned for its aphrodisiac abilities. Middle East herbalists have utilized Ferula hermonis seed and root as an aphrodisiac folk medicine to treat women's frigidity and male erectile and sexual dysfunction., Aim of the Study: Assessment of follicle-stimulating hormone-like (FSH), luteinizing hormone-like (LH), and estrogenic activities of the methanolic extract (ME) of the roots of Ferula hermonis on female reproductive function., Materials and Methods: The methanolic extract was prepared from the root of F. hermonis and studied at dose level 6 mg/kg in immature female rats for FSH-like, LH-like, and estrogenic activities. These activities were determined by analyzing gross anatomical features, relative organ weight, and serum level of FSH, LH, progesterone and estrogen hormones, and histopathological characteristics. Quantification of the main phytoestrogenic component ferutinin carried out by HPLC. In addition, molecular docking for the binding affinity of ferutinin inside active sites of both estrogen receptor alpha (ERα) and FSH receptor (FSHR) was performed to predict the potential role of ferutinin in regulating the female reproductive process., Results: Ferula hermonis (ME) showed potent FSH-like, LH-like activities and moderate estrogenic effect at the dose of 6 mg/kg. The content of ferutinin in F. hermonis was estimated to be 92 ± 1.33 mg/g of the methanolic extract. Molecular docking of ferutinin with ERα and FSHR displayed strong interaction with target proteins., Conclusions: Based on results, it can be concluded that Ferula hermonis can be considered as a suitable female fertility improving agent., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Post-traumatic trigeminal neuropathy (PTTN) is a chronic sensory disorder that afflicts patients with nerve injury caused by orofacial and dental surgery or cervicofacial trauma. Currently, effective treatment strategies for PTTN are lacking, and patients treated with conventional drugs for PTTN experience adverse effects such as drowsiness and drug addiction. In the present study, we investigated whether mirogabalin, a novel gabapentinoid, could be an effective treatment for PTTN induced by distal infraorbital nerve chronic constriction injury (dIoN-CCI) in the mouse. Increased facial grooming time and hyper-responsiveness to acetone were observed in dIoN-CCI mice. These pain-related behaviors were attenuated by intraperitoneal injection of mirogabalin. In particular, mirogabalin significantly diminished the increase in facial grooming time. The analgesic effect of mirogabalin injection started 45 min after the injection and persisted for 6 h. Additionally, 10 mg/kg mirogabalin did not affect locomotor activity in the open field test, suggesting that it does not cause sedation. Together, the current findings suggest that mirogabalin could be a valuable therapeutic drug for PTTN following orofacial surgeries without sedative side effects., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The α7 nicotinic acetylcholine receptor (nAChR) is widely distributed in the central and peripheral nervous systems and is closely related to a variety of nervous system diseases and inflammatory responses. The α7 nAChR subtype plays a vital role in the cholinergic anti-inflammatory pathway. In vivo, ACh released from nerve endings stimulates α7 nAChR on macrophages to regulate the NF-κB and JAK2/STAT3 signaling pathways, thereby inhibiting the production and release of downstream proinflammatory cytokines and chemokines. Despite a considerable level of recent research on α7 nAChR-mediated immune responses, much is still unknown. In this study, we used an agonist (PNU282987) and antagonists (MLA and α-conotoxin [A10L]PnIA) of α7 nAChR as pharmacological tools to identify the molecular mechanism of the α7 nAChR-mediated cholinergic anti-inflammatory pathway in RAW264.7 mouse macrophages. The results of quantitative PCR, ELISAs, and transcriptome analysis were combined to clarify the function of α7 nAChR regulation in the inflammatory response. Our findings indicate that the agonist PNU282987 significantly reduced the expression of the IL-6 gene and protein in inflammatory macrophages to attenuate the inflammatory response, but the antagonists MLA and α-conotoxin [A10L]PnIA had the opposite effects. Neither the agonist nor antagonists of α7 nAChR changed the expression level of the α7 nAChR subunit gene; they only regulated receptor function. This study provides a reference and scientific basis for the discovery of novel α7 nAChR agonists and their anti-inflammatory applications in the future.

Chiral sp 3 -rich bicyclo[3.3.1]nonane scaffolds 10-12 were synthesized as single diastereomers from aldehyde 9, which was prepared from 4,4-dimethoxycyclohexa-2,5-dienone through a copper-catalyzed enantioselective reduction. Three different types of intramolecular addition reactions were studied: SmI 2 -mediated reductive cyclization, base-promoted aldol reaction, and one-pot Mannich reaction. We succeeded in introducing three side-chains to scaffold 11 and construct an sp 3 -rich compound library in both enantiomeric variants by simply changing the chirality of the ligands. The biological evaluation revealed that all synthesized compounds exhibited a concentration-dependent inhibition of hypoxia-inducible factor-1 (HIF-1) transcriptional activity, with IC 50 values in the range of 17.2-31.7 µM, whereas their effects on cell viability were varied (IC 50  = 3.5 to > 100 µM). The most active compound 16f inhibits the accumulation of HIF-1α protein and mRNA in hypoxia, indicating that it has a mechanism of action distinctly different from other known compounds bearing the common bicyclo[3.3.1]nonane skeleton., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

BACKGROUND To reveal the mechanism underlying the effect of alpha7 nicotinic acetylcholine receptor (nAChR) on neurodegeneration in Alzheimer disease (AD), the influence of the receptor on recognition in APP/PS1 mice was evaluated by using its selective agonist (PNU-282987). MATERIAL AND METHODS APP/PS1 and wild-type (WT) mice were treated with PNU or saline, respectively, for 7 days at the ages of 6 and 10 months. RESULTS Morris water maze analysis showed that both at 6 and 10 months of age, PNU treatment enhanced the learning and memory of APP/PS1 mice. However, PNU treatment did not alter the number of senile plaques. Furthermore, a higher protein expression of Nrf2/HO-1, ADAM10, SYP, and SNAP-25, and a lower level of oxidative stress, were observed in the hippocampus of APP/PS1 mice treated with PNU compared with the control group. CONCLUSIONS The results indicated that the activation of alpha7 nAChR by PNU improved the learning and memory of mice carrying the APP/PS1 mutation, regulated the levels of enzymes that mediate APP metabolization to reduce ß-amyloid peptide damage, and decreased the level of oxidative stress and maintained synaptic plasticity, in which the mechanism might be enhancement of the Nrf2/HO-1 pathway.

Osteoarthritis (OA) is a chronic degenerative joint disease characterized by cartilage degradation. Alpha 7 nicotinic acetylcholine receptor (α7nAChR) is associated with inflammatory and metabolic responses in OA. However, the mechanisms underlying the pathological process of OA remain unclear. The aim of the present study was to examine the role and mechanisms of α7nAChR-mediated autophagy and anti-inflammatory response in chondroprotection. Monosodium iodoacetate (MIA)-induced Wistar rat OA model was used to assess the in vivo effects of the ɑ7nAChR agonist (PNU-282987). The histopathological characteristics of OA were evaluated by immunohistochemistry (IHC), and the levels of autophagy markers were determined by western blotting and transmission electron microscopy. The anti-inflammatory effect of the ɑ7nAChR agonist was assessed by IHC, quantitative real-time polymerase chain reaction, and western blotting. Parallel experiments to determine the molecular mechanisms through which the ɑ7nAChR agonist prevents OA were performed using interleukin-1β (IL-1β)-treated chondrocytes. Our results showed that PNU-282987 reduced cartilage degeneration and matrix metalloproteinase (MMP)-1 and MMP-13 expressions. Activating α7nAChR with PNU-282987 significantly promoted MIA/IL-1β-induced chondrocyte autophagy, as demonstrated by the increase in LC3-II/LC3-I ratio, Beclin-1 levels, and autophagosome number. Furthermore, treating chondrocyte with ULK1 siRNA attenuated the PNU282987-induced enhancement of LC3-II/LC3-I ratio and Beclin-1 level. Additionally, PNU282987 suppressed NF-κB/NLRP3 inflammasome activation by inhibiting the ROS/TXNIP pathway and suppressed tumor necrosis factor-ɑ and IL-1β secretion in MIA/IL-1β-treated chondrocytes. Our results demonstrate that the activation of α7nAChR promotes chondrocyte autophagy and attenuates inflammation to mitigate OA progression, providing a novel target for the treatment of OA., Competing Interests: The authors have declared that no competing interests exist.

Purpose: Antagonising serotonin (5-HT) type 2A receptors (5-HT 2A R) is an effective strategy to alleviate both dyskinesia and psychosis in Parkinson's disease (PD). We have recently shown that activation of metabotropic glutamate 2 receptors (mGluR 2 ), via either orthosteric stimulation or positive allosteric modulation, enhances the anti-dyskinetic and anti-psychotic effects of 5-HT 2A R antagonism. Here, we investigated if greater therapeutic efficacy would be achieved by combining 5-HT 2A R antagonism with concurrent mGluR 2 orthosteric stimulation and mGluR 2 positive allosteric modulation., Methods: Five 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned marmosets exhibiting dyskinesia and psychosis-like behaviours (PLBs) were administered L-3,4-dihydroxyphenylalanine (L-DOPA) in combination with vehicle or the 5-HT 2A R antagonist EMD-281,014. EMD-281,014 was itself administered alone or with the mGluR 2 orthosteric agonist (OA) LY-354,740, the mGluR 2 positive allosteric modulator (PAM) LY-487,379 and combination thereof, after which the severity of dyskinesia, PLBs and parkinsonism was rated., Results: EMD-281,014 reduced dyskinesia and PLBs by up to 47% and 40%, respectively (both P < 0.001). The addition of LY-354,740, LY-487,379 and LY-354,740/LY-487,379 decreased dyskinesia by 56%, 65% and 77%, while PLBs were diminished by 55%, 63% and 71% (all P < 0.001). All treatment combinations provided anti-dyskinetic and anti-psychotic benefits significantly greater than those conferred by EMD-281,014 alone (all P < 0.05). The combination of EMD-281,014/LY-354,740/LY-487,379 resulted in anti-dyskinetic and anti-psychotic effects significantly greater than those conferred by EMD-281,014 with either LY-354,740 or LY-487,379 (both P < 0.05). No deleterious effects on L-DOPA anti-parkinsonian action were observed., Conclusion: Our results suggest that combining 5-HT 2A R antagonism with mGluR 2 activation results in greater reduction of L-DOPA-induced dyskinesia and PD psychosis. They also indicate that further additive effect can be achieved when a mGluR 2 OA and a mGluR 2 PAM are combined with a 5-HT 2A R antagonist than when a mGluR 2 OA or a mGluR 2 PAM are added to a 5-HT 2A R antagonist., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Cholinergic anti-inflammatory pathway (CAP) is implicated in cardioprotection in chronic heart failure (CHF) by downregulating inflammation response. Mitochondrial injuries play an important role in ventricular remodeling of the CHF process. Herein, we aim to investigate whether CAP elicitation prevents ventricular remodeling in CHF by protecting myocardial mitochondrial injuries and its underlying mechanisms., Methods and Results: CHF models were established by ligation of anterior descending artery for 5 weeks. Postoperative survival rats were assigned into 5 groups: the sham group (sham, n = 10), CHF group (CHF, n = 11), Vag group (CHF+vagotomy, n = 10), PNU group (CHF+PNU-282987 for 4 weeks, n = 11), and Vag+PNU group (CHF+vagotomy+PNU-282987 for 4 weeks, n = 10). The antiventricular remodeling effect of cholinergic elicitation was evaluated in vivo, and H9C2 cells were selected for the TNF- α gradient stimulation experiment in vitro. In vivo, CAP agitated by PNU-282987 alleviated the left ventricular dysfunction and inhibited the energy metabolism remodeling. Further, cholinergic elicitation increased myocardium ATP levels and reduced systemic inflammation. CAP induction alleviates macrophage infiltration and cardiac fibrosis, of which the effect is counteracted by vagotomy. Myocardial mitochondrial injuries were ameliorated by CAP activation, including the reserved ultrastructural integrity, declining ROS overload, reduced myocardial apoptosis, and enhanced mitochondrial fusion. In vitro, TNF- α intervention significantly exacerbated the mitochondrial damage in H9C2 cells., Conclusion: CAP elicitation effectively improves ischemic ventricular remodeling by suppressing systemic and cardiac inflammatory response, attenuating cardiac fibrosis and potentially alleviating the mitochondrial dysfunction linked to hyperinflammation reaction., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Yang Zhao et al.)

The dithiol reagents phenylarsine oxide (PAO) and dibromobimane (DBrB) have opposite effects on the F 1 F O -ATPase activity. PAO 20% increases ATP hydrolysis at 50 μM when the enzyme activity is activated by the natural cofactor Mg 2+ and at 150 μM when it is activated by Ca 2+ . The PAO-driven F 1 F O -ATPase activation is reverted to the basal activity by 50 μM dithiothreitol (DTE). Conversely, 300 μM DBrB decreases the F 1 F O -ATPase activity by 25% when activated by Mg 2+ and by 50% when activated by Ca 2+ . In both cases, the F 1 F O -ATPase inhibition by DBrB is insensitive to DTE. The mitochondrial permeability transition pore (mPTP) formation, related to the Ca 2+ -dependent F 1 F O -ATPase activity, is stimulated by PAO and desensitized by DBrB. Since PAO and DBrB apparently form adducts with different cysteine couples, the results highlight the crucial role of cross-linking of vicinal dithiols on the F 1 F O -ATPase, with (ir)reversible redox states, in the mPTP modulation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Spreading depolarization is a slowly propagating wave of massive cellular depolarization associated with acute brain injury and migraine aura. Genetic studies link depolarizing molecular defects in Ca2+ flux, Na+ current in interneurons, and glial Na+-K+ ATPase with spreading depolarization susceptibility, emphasizing the important roles of synaptic activity and extracellular ionic homeostasis in determining spreading depolarization threshold. In contrast, although gene mutations in voltage-gated potassium ion channels that shape intrinsic membrane excitability are frequently associated with epilepsy susceptibility, it is not known whether epileptogenic mutations that regulate membrane repolarization also modify spreading depolarization threshold and propagation. Here we report that the Kcnq2/Kv7.2 potassium channel subunit, frequently mutated in developmental epilepsy, is a spreading depolarization modulatory gene with significant control over the seizure-spreading depolarization transition threshold, bi-hemispheric cortical expression, and diurnal temporal susceptibility. Chronic DC-band cortical EEG recording from behaving conditional Kcnq2 deletion mice (Emx1cre/+::Kcnq2flox/flox) revealed spontaneous cortical seizures and spreading depolarization. In contrast to the related potassium channel deficient model, Kv1.1-KO mice, spontaneous cortical spreading depolarizations in Kcnq2 cKO mice are tightly coupled to the terminal phase of seizures, arise bilaterally, and are observed predominantly during the dark phase. Administration of the non-selective Kv7.2 inhibitor XE991 to Kv1.1-KO mice partly reproduced the Kcnq2 cKO-like spreading depolarization phenotype (tight seizure coupling and bilateral symmetry) in these mice, indicating that Kv7.2 currents can directly and actively modulate spreading depolarization properties. In vitro brain slice studies confirmed that Kcnq2/Kv7.2 depletion or pharmacological inhibition intrinsically lowers the cortical spreading depolarization threshold, whereas pharmacological Kv7.2 activators elevate the threshold to multiple depolarizing and hypometabolic spreading depolarization triggers. Together these results identify Kcnq2/Kv7.2 as a distinctive spreading depolarization regulatory gene, and point to spreading depolarization as a potentially significant pathophysiological component of KCNQ2-linked epileptic encephalopathy syndromes. Our results also implicate KCNQ2/Kv7.2 channel activation as a potential adjunctive therapeutic target to inhibit spreading depolarization incidence., (© The Author(s) (2021). Published by Oxford University Press on behalf of the Guarantors of Brain.)

Conformationally restricted bicyclic KOR agonists 10 with an endo -configured amino moiety were synthesized to analyze the bioactive conformation of conformationally flexible KOR agonists such as 2-5. A seven-step synthesis starting with ( S )-configured 4-oxopiperidine-2-carboxylate 13 was developed. cis - and trans -configured diesters 12 were obtained in a 3 : 1 ratio via hydrogenation of the α,β-unsaturated ester 14. After establishment of the bicyclic scaffold, a diastereoselective reductive amination of ketone 11 provided exclusively the endo -configured bicyclic amines 10a,b. The 3 : 1 mixtures of enantiomers were separated by chiral HPLC, respectively, leading to enantiomerically pure KOR agonists (1 S ,5 S ,7 R )-10a,b and (1 R ,5 R ,7 S )-10a,b ( ent -10a,b). The KOR affinity was determined in receptor binding studies with the radioligand [ 3 H]U-69 593. The high KOR affinity of endo -configured amines 10a ( K i = 7 nM) and 10b ( K i = 13 nM) indicates that the dihedral angle of the KOR pharmacophoric element N(pyrrolidine)-C-C-N(phenylacetyl) of 42° is close to the bioactive conformation of more flexible KOR agonists. It should be noted that changing the configuration of potent and selective KOR agonists 10a and 10b led to potent and selective σ 1 ligands ( e.g. ent -10a K i ( σ 1 ) = 10 nM).

Epidemiological and clinical studies have demonstrated that excessive salt intake causes severe hypertension and exacerbates organ derangement, such as in chronic kidney disease (CKD). In this study, we focused on evaluating the histological and gene expression effects in the kidneys of stroke-prone spontaneously hypertensive rats (SHRSP) with a high salt intake and the thromboxane A 2 / prostaglandin H 2 receptor (TPR) blocker ONO-8809. Six-week-old SHRSPs were divided into three groups and were fed normal chow containing 0.4% NaCl, 2.0%NaCl or 2.0%NaCl + ONO-8809 (0.6 mg/kg p.o. daily). Histological analyses with immunohistochemistry and a gene expression assay with a DNA kidney microarray were performed after 8 weeks. The following changes were observed in SHRSPs with the high salt intake. Glomerular sclerotic changes were remarkably observed in the juxtamedullary cortex areas. The ED1, monocyte chemoattractant protein-1 (MCP-1), nitrotyrosine and hypoxia inducible factor 1α (HIF-1α) staining areas were increased in the glomeruli and interstitial portion of the kidneys. The genes Tbxa2r (that encodes TPR), Prcp and Car7 were significantly underexpressed in the kidneys. The plasma 8-isoprostane level was significantly elevated and was attenuated with the ONO-8809 treatment. Thromboxane A 2 (TXA 2 ) and oxidative stress exaggerated renal dysfunction in the salt-loaded SHRSPs, and ONO-8809 as a TPR blocker suppressed these changes. Therefore, ONO-8809 is a candidate drug to prevent CKD in hypertensive patients when CKD is associated with a high salt intake., (© 2021 The Authors. Clinical and Experimental Pharmacology and Physiology published by John Wiley & Sons Australia, Ltd.)

Background: Though drugs binding to serotonergic 5-HT2A receptors have long been claimed to influence human anxiety, it remains unclear if this receptor subtype is best described as anxiety promoting or anxiety dampening. Whereas conditioned fear expressed as freezing in rats is modified by application of 5-HT2A-acting drugs locally into different brain regions, reports on the effect of systemic administration of 5-HT2A receptor agonists and 5-HT2A antagonists or inverse agonists on this behavior remain sparse., Methods: We assessed the possible impact of systemic administration of 5-HT2A receptor agonists, 5-HT2A receptor inverse agonists, and a selective serotonin reuptake inhibitor (SSRI)-per se or in combination-on the freezing displayed by male rats when re-exposed to a conditioning chamber in which they received foot shocks 7 days earlier., Results: The 5-HT2A receptor agonists psilocybin and 25CN-NBOH induced a reduction in conditioned fear that was countered by pretreatment with 5-HT2A receptor inverse agonist MDL 100907. While both MDL 100907 and another 5-HT2A receptor inverse agonist, pimavanserin, failed to impact freezing per se, both compounds unmasked a robust fear-reducing effect of an SSRI, escitalopram, which by itself exerted no such effect., Conclusions: The results indicate that 5-HT2A receptor activation is not a prerequisite for normal conditioned freezing in rats but that this receptor subtype, when selectively over-activated prior to expression, exerts a marked fear-reducing influence. However, in the presence of an SSRI, the 5-HT2A receptor, on the contrary, appears to counter an anti-freezing effect of the enhanced extracellular serotonin levels following reuptake inhibition., (© The Author(s) 2021. Published by Oxford University Press on behalf of CINP.)

Much hope in drug development comes from the discovery of positive allosteric modulators (PAM) that display target subtype selectivity and act by increasing agonist potency and efficacy. How such compounds can allosterically influence agonist action remains unclear. Metabotropic glutamate receptors (mGlu) are G protein-coupled receptors that represent promising targets for brain diseases, and for which PAMs acting in the transmembrane domain have been developed. Here, we explore the effect of a PAM on the structural dynamics of mGlu2 in optimized detergent micelles using single molecule FRET at submillisecond timescales. We show that glutamate only partially stabilizes the extracellular domains in the active state. Full activation is only observed in the presence of a PAM or the G i protein. Our results provide important insights on the role of allosteric modulators in mGlu activation, by stabilizing the active state of a receptor that is otherwise rapidly oscillating between active and inactive states., (© 2021. The Author(s).)

The adult mammal lacks the ability to regenerate neurons lost to retinal damage or disease in a meaningful capacity. However, previous studies from this laboratory have demonstrated that PNU-282987, an α7 nicotinic acetylcholine receptor agonist, elicits a robust neurogenic response in the adult murine retina. With eye drop application of PNU-282987, Müller glia cells re-enter the cell cycle and produce progenitor-like cells that can differentiate into various types of retinal neurons. In this study, we analyzed the regenerative capability of PNU-282987 in two retinal disease models and identified the source of newly regenerated neurons. Wild-type mice and mice with a transgenic Müller-glia lineage tracer were manipulated to mimic loss of retinal cells associated with glaucoma or photoreceptor degeneration. Following treatment with PNU-282987, the regenerative response of retinal neurons was quantified and characterized. After onset of photoreceptor degeneration, PNU-282987 was able to successfully regenerate both rod and cone photoreceptors. Quantification of this response demonstrated significant regeneration, restoring photoreceptors to near wild-type density. In mice that had glaucoma-like conditions induced, PNU-282987 treatment led to a significant increase in retinal ganglion cells. Retrograde labeling of optic nerve axon fibers demonstrated that newly regenerated axons projected into the optic nerve. Lineage tracing analysis demonstrated that these new neurons were derived from Müller glia. These results demonstrate that PNU-282987 can induce retinal regeneration in adult mice following onset of retinal damage. The ability of PNU-282987 to regenerate retinal neurons in a robust manner offers a new direction for developing novel and potentially transformative treatments to combat neurodegenerative disease., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Bacterial infections can cause serious problems that threaten public health over a long period of time. Moreover, the continuous emergence of drug-resistant bacteria necessitates the development of novel antibacterial agents. D-alanyl-D-alanine ligase (Ddl) is an indispensable adenosine triphosphate-dependent bacterial enzyme involved in the biosynthesis of peptidoglycan precursor, which catalyzes the ligation of two D-alanine molecules into one D-alanyl-D-alanine dipeptide. This dipeptide is an essential component of the intracellular peptidoglycan precursor, uridine diphospho-N-acetylmuramic acid (UDP-MurNAc)-pentapeptide, that maintains the integrity of the bacterial cell wall by cross-linking the peptidoglycan chain, and is crucial for the survival of pathogens. Consequently, Ddl is expected to be a promising target for the development of antibacterial agents. In this review, we present a brief introduction regarding the structure and function of Ddl, as well as an overview of the various Ddl inhibitors currently being used as antibacterial agents, specifically highlighting their inhibitory activities, structure-activity relationships and mechanisms of action., (© 2021 John Wiley & Sons A/S.)

Fall armyworm (Spodoptera frugiperda) is a major global pest of many crops, including maize (Zea mays). This insect is known to use host plant-derived volatile organic compounds to locate suitable hosts during both its adult and larval stages, yet the function of individual compounds remains mostly enigmatic. In this study, we use a combination of volatile profiling, electrophysiological assays, pair-wise choice behavioral assays, and chemical supplementation treatments to identify and assess specific compounds from maize that influence S. frugiperda host location. Our findings reveal that methyl salicylate and (E)-alpha-bergamotene are oviposition attractants for adult moths but do not impact larval behavior. While geranyl acetate can act as an oviposition attractant or repellent depending on the host volatile context and (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) is an oviposition deterrent. These compounds can also be attractive to the larvae when applied to specific maize inbreds. These data show that S. frugiperda uses different plant volatile cues for host location in its adult and larval stage and that the background volatile context that specific volatiles are perceived in, alters their impact as behavioral cues., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

A novel norditerpenoid, sinusiaetone A ( 1 ), featuring an uncommon bicyclo[11.3.0]hexadecane carbon skeleton, and four polyoxygenated cembranoids ( 2-5 ) were isolated from the Hainan soft coral Sinularia siaesensis . Their structures were established by spectroscopic analysis, X-ray diffraction, quantum chemical computational approaches, and/or a modified Mosher's method. A plausible biosynthetic pathway of 1 and its biogenetic relationship with 2-5 were proposed. New compounds 1-3 displayed an interesting inhibitory activity against lipopolysaccharide-induced inflammation in BV-2 microglial cells.

Osteoporosis is a common disease in post-menopausal women. The increased risk of breast cancer and malignancy with hormone replacement, hampers its wide-usage. Phytoestrogens are known to have selective estrogen receptor modulator activity. The present study aims to determine how ferutinin affects unrestricted human Somatic Stem Cells (USSCs) osteogenic differentiation. The effect of ferutinin on USSCs proliferation was assessed by MTT assay while osteogenesis was evaluated using Alkaline Phosphatase Activity (ALP), calcium deposition and Alizarin Red Staining. Quantitative real-time PCR was applied to examine the expression of bone specific genes such as osteocalcin, Runx 2 , and BMP- 2 . Ferutinin (5-15 µg/mL) could positively impact on the proliferation of cells in a dose-dependent manner. Also, ALP enzyme activity and calcium deposition were enhanced in the presence of ferutinin. Based on real-time PCR results, ferutinin could increase the expression of bone marker genes. The pattern of ferutinin effect on gene expression is similar to standard synthetic estrogen, 17-β-estradiol. In the presence of the estrogen activity inhibitor (ICI), the effect of ferutinin on ALP and gene level was diminished. In conclusion, ferutinin may be considered as a potential candidate for the stem cell therapy in osteoporosis., (Copyright © 2021 Elsevier Inc. All rights reserved.)

In recent decades, interest in natural compounds has increased exponentially due to their numerous beneficial properties in the treatment of various acute and chronic diseases. A group of plant derivatives with great scientific interest is terpenic compounds. Among the plants richest in terpenes, the genus Ferula L. is one of the most representative, and ferutinin, the most common sesquiterpene, is extracted from the leaves, rhizome, and roots of this plant. As reported in the scientific literature, ferutinin possesses antioxidant and anti-inflammatory properties, as well as valuable estrogenic properties. Neurodegenerative and demyelinating diseases are devastating conditions for which a definite cure has not yet been established. The mechanisms involved in these diseases are still poorly understood, and oxidative stress is considered to be both a key modulator and a common denominator. In the proposed experimental system, co-cultured human neurons (SH-SY5Y) and human oligodendrocytes (MO3.13) were treated with the pro-inflammatory agent lipopolysaccharide at a concentration of 1 μg/mL for 24 h or pretreated with ferutinin (33 nM) for 24 h and subsequently exposed to lipopolysaccharide 1 μg/mL for 24 h. Further studies would, however, be needed to establish whether this natural compound can be used as a support strategy in pathologies characterized by progressive inflammation and oxidative stress phenomena.

Inflammation as a host's excessive immune response to stimulation, is involved in the development of numerous diseases. To discover novel anti-inflammatory agents and based on our previous synthetic work on marine natural product Chrysamide B, it and a series of derivatives were synthesized and evaluated for their anti-inflammatory activity on inhibition of LPS-induced NO production. Then the preliminary structure-activity relationships were conducted. Among them, Chrysamide B is the most potent anti-inflammatory agent with low cytotoxicity and strong inhibition on the production of NO (IC 50  = 0.010 μM) and the activity of iNOS (IC 50  = 0.082 μM) in LPS-stimulated RAW 264.7 cells. Primary studies suggested that the mechanism of action may be that it interfered the formation of active dimeric iNOS but not affected transcription and translation. Furthermore, its good performance of anti-inflammatory effect on LPS-induced multiple inflammatory cytokines production, carrageenan-induced paw edema, and endotoxin-induced septic mice, was observed. We believe that these findings would provide an idea for the further modification and research of these analogs in the future., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

(1) Background: The lung cholinergic pathway is important for controlling pulmonary inflammation in acute lung injury, a condition that is characterized by a sudden onset and intense inflammation. This study investigated changes in the expression levels of nicotinic and muscarinic acetylcholine receptors (nAChR and mAChR) in the lung during acute lung injury. (2) Methods: acute lung injury (ALI) was induced in wild-type and cholinergic-deficient (VAChT-KD HOM ) mice using intratracheal lipopolysaccharide (LPS) instillation with or without concurrent treatment with nicotinic ligands. Bronchoalveolar lavage fluid was collected to evaluate markers of inflammation, and then the lung was removed and processed for isolation of membrane fraction and determination of acetylcholine receptors level using radioligand binding assays. (3) Results: LPS-induced increase in lung inflammatory markers (e.g., neutrophils and IL-1β) was significantly higher in VAChT-KD HOM than wild-type mice. In contrast, LPS treatment resulted in a significant increase in lung's α7 nicotinic receptor level in wild-type, but not in VAChT-KD HOM mice. However, treatment with PNU 282987, a selective α7 nicotinic receptor agonist, restored VAChT-KD HOM mice's ability to increase α7 nicotinic receptor levels in response to LPS-induced acute lung injury and reduced lung inflammation. LPS also increased muscarinic receptors level in VAChT-KD HOM mice, and PNU 282987 treatment reduced this response. (4) Conclusions: Our data indicate that the anti-inflammatory effects of the lung cholinergic system involve an increase in the level of α7 nicotinic receptors. Pharmacological agents that increase the expression or the function of lung α7 nicotinic receptors have potential clinical uses for treating acute lung injury.

Mirogabalin is a novel potent and selective ligand for the α 2 δ subunit of voltage-gated calcium channels, and shows potent and sustained analgesic effects in neuropathic pain and fibromyalgia models. Fibromyalgia is often associated with multiple comorbid symptoms, such as anxiety, depression and cognitive impairment. In the present study, we investigated the effects of mirogabalin on cognitive impairments in an experimental animal model for fibromyalgia, repeated intramuscular acidic saline injection model (Sluka model) rats. Male rats received two repeated intramuscular injections of pH 4 acidic saline into their gastrocnemius muscle. After developing mechanical hypersensitivity as identified in the von Frey test, the animals received the test substance orally once daily for 13 days and were subjected to four cognitive function tests, (Y-maze, novel object recognition, Morris water maze and step-through passive avoidance). Sluka model rats showed cognitive impairments in all four tests. Oral administration of mirogabalin (3 and 10 mg/kg) improved the cognitive impairments in these rats. In conclusion, mirogabalin improved the impaired cognitive function in Sluka model rats. It may thus also alleviate cognitive impairments as well as painful symptoms in fibromyalgia patients., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Marine natural products derived from special or extreme environment provide an important source for the development of anti-tumor drugs due to their special skeletons and functional groups. In this study, based on our previous work on the total synthesis and structure revision of the novel marine natural product Chrysamide B, a group of its derivatives were designed, synthesized, and subsequently of which the anti-cancer activity, structure-activity relationships and cellular mechanism were explored for the first time. Compared with Chrysamide B, better anti-cancer performance of some derivatives against five human cancer cell lines (SGC-7901, MGC-803, HepG2, HCT-116, MCF-7) was observed, especially for compound b-9 on MGC-803 and SGC-7901 cells with the IC 50 values of 7.88 ± 0.81 and 10.08 ± 1.08 μM, respectively. Subsequently, cellular mechanism study suggested that compound b-9 treatment could inhibit the cellular proliferation, reduce the migration and invasion ability of cells, and induce mitochondrial-dependent apoptosis in gastric cancer MGC-803 and SGC-7901 cells. Furthermore, the mitochondrial-dependent apoptosis induced by compound b-9 is related with the JAK2/STAT3/Bcl-2 signaling pathway. To conclude, our results offer a new structure for the discovery of anti-tumor lead compounds from marine natural products., (Copyright © 2021 Elsevier Inc. All rights reserved.)