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Background and purpose: Stress is a stimulus that leads to a physical or psychological reaction. Stress affects memory and cognition. Common drugs for treating stress and memory disorders have limited effects and many side effects, so the search for new effective compounds with natural origin and fewer side effects is of interest. Various studies have shown that Terminalia chebula) T. chebula (and crocin are effective in improving memory. Several proteins, including synapsin-1, synaptophysin, and PSD95, are involved in the transmission of nerve messages in synapses involved in memory. In this study, the effect of the hydroalcoholic extract of T. chebula and crocin in improving memory and stress and the expression of synaptophysin, PSD 95, and synapsin-1 genes in the hippocampal tissue of male rats of the immobility stress model has been evaluated. Materials and methods: 25 adult male Wistar rats were randomly divided into five groups, including a control group, a stress group, treated with hydroalcoholic extract of T. chebula group, treated with crocin group, simultaneously treated with hydroalcoholic extract of T. chebula, and crocin group. All groups except the control group were subjected to immobility stress for 14 days. Crocin was injected intraperitoneally (30 mg/kg) and hydroalcoholic extract of T. chebula was given as intragastric gavage (50 mg/kg). After fourteen days, the shuttle box test was performed to check the memory, then the animals were anesthetized and their hippocampal tissue was isolated, and the expression changes of synapsin-1, synaptophysin, and PSD 95 genes in the tissue were analyzed by Real-time PCR method. Results: Immobility stress caused disruption in two memory indicators, i.e. increased the duration of staying in the dark chamber (P˂0.01) and decreased the latency time to enter the dark chamber compared to the control group (P˂0.0001). Treatment with the alcoholic extract of T. chebula did not affect the duration of staying in the dark chamber (P>0.05), but crocin decreased it compared to the stress group (P˂0.05). The hydroalcoholic extract of T. chebula and crocin increased the latency time to enter the dark chamber compared to the stress group (P˂0.01 and P˂0.001, respectively). As a result, both of them affected memory improvement parameters. The combination of the hydroalcoholic extract of T. chebula and crocin decreased the duration of staying in the dark chamber (P˂0.05) and increased the latency time to enter the dark chamber compared to the stress group (P˂0.001). Also, Immobility stress decreased the expression of synaptophysin, synapsin-1, and PSD95 genes in the hippocampus tissue compared to the control group (P˂0.001 for all genes). The expression of synaptophysin, synapsin-1, and PSD95 genes in the hippocampus tissue of groups treated with hydroalcoholic extract of T. chebula (P˂0.01, P˂0.01 and P˂0.001, respectively), crocin (P˂0.001, P˂0.01 and P˂0.001, respectively), and their combination (P˂0.001, P˂0.001 and P˂0.01, respectively), increased compared to the stress group. Conclusion: treatment with crocin and hydroalcoholic extract of T. chebula separately or their combination was effective in improving memory and reducing stress by increasing the expression of synapsin 1, synaptophysin, and PSD95 genes.

Background and purpose: Stress is a stimulus that leads to a physical or psychological reaction. Stress affects memory and cognition. Common drugs for treating stress and memory disorders have limited effects and many side effects, so the search for new effective compounds with natural origin and fewer side effects is of interest. Various studies have shown that Terminalia chebula )T. chebula( and crocin are effective in improving memory. Several proteins, including synapsin-1, synaptophysin, and PSD95, are involved in the transmission of nerve messages in synapses involved in memory .In this study, the effect of the hydroalcoholic extract of T. chebula and crocin in improving memory and stress and the expression of synaptophysin, PSD 95, and synapsin-1 genes in the hippocampal tissue of male rats of the immobility stress model has been evaluated. Materials and methods: 25 adult male Wistar rats were randomly divided into five groups, including a control group, a stress group, treated with hydroalcoholic extract of T. chebula group, treated with crocin group, simultaneously treated with hydroalcoholic extract of T. chebula, and crocin group. All groups except the control group were subjected to immobility stress for 14 days. Crocin was injected intraperitoneally (30 mg/kg) and hydroalcoholic extract of T. chebula was given as intragastric gavage (50 mg/kg). After fourteen days, the shuttle box test was performed to check the memory, then the animals were anesthetized and their hippocampal tissue was isolated, and the expression changes of synapsin-1, synaptophysin, and PSD 95 genes in the tissue were analyzed by Real-time PCR method. Results: Immobility stress caused disruption in two memory indicators, i.e. increased the duration of staying in the dark chamber (P˂0.01) and decreased the latency time to enter the dark chamber compared to the control group (P˂0.0001). Treatment with the alcoholic extract of T. chebula did not affect the duration of staying in the dark chamber (P>0.05), but crocin decreased it compared to the stress group (P˂0.05). The hydroalcoholic extract of T. chebula and crocin increased the latency time to enter the dark chamber compared to the stress group (P˂0.01 and P˂0.001, respectively). As a result, both of them affected memory improvement parameters. The combination of the hydroalcoholic extract of T. chebula and crocin decreased the duration of staying in the dark chamber (P˂0.05) and increased the latency time to enter the dark chamber compared to the stress group (P˂0.001). Also, Immobility stress decreased the expression of synaptophysin, synapsin-1, and PSD95 genes in the hippocampus tissue compared to the control group (P˂0.001 for all genes). The expression of synaptophysin, synapsin-1, and PSD95 genes in the hippocampus tissue of groups treated with hydroalcoholic extract of T. chebula (P˂0.01, P˂0.01 and P˂0.001, respectively), crocin (P˂0.001, P˂0.01 and P˂0.001, respectively), and their combination (P˂0.001, P˂0.001 and P˂0.01, respectively), increased compared to the stress group. Conclusion: treatment with crocin and hydroalcoholic extract of T. chebula separately or their combination was effective in improving memory and reducing stress by increasing the expression of synapsin 1, synaptophysin, and PSD95 genes. [ABSTRACT FROM AUTHOR]

Abstract Background Bidirectional communication between presynaptic and postsynaptic components contribute to the homeostasis of the synapse. In the neuromuscular synapse, the arrival of the nerve impulse at the presynaptic terminal triggers the molecular mechanisms associated with ACh release, which can be retrogradely regulated by the resulting muscle contraction. This retrograde regulation, however, has been poorly studied. At the neuromuscular junction (NMJ), protein kinase A (PKA) enhances neurotransmitter release, and the phosphorylation of the molecules of the release machinery including synaptosomal associated protein of 25 kDa (SNAP-25) and Synapsin-1 could be involved. Methods Accordingly, to study the effect of synaptic retrograde regulation of the PKA subunits and its activity, we stimulated the rat phrenic nerve (1 Hz, 30 min) resulting or not in contraction (abolished by µ-conotoxin GIIIB). Changes in protein levels and phosphorylation were detected by western blotting and cytosol/membrane translocation by subcellular fractionation. Synapsin-1 was localized in the levator auris longus (LAL) muscle by immunohistochemistry. Results Here we show that synaptic PKA Cβ subunit regulated by RIIβ or RIIα subunits controls activity-dependent phosphorylation of SNAP-25 and Synapsin-1, respectively. Muscle contraction retrogradely downregulates presynaptic activity-induced pSynapsin-1 S9 while that enhances pSNAP-25 T138. Both actions could coordinately contribute to decreasing the neurotransmitter release at the NMJ. Conclusion This provides a molecular mechanism of the bidirectional communication between nerve terminals and muscle cells to balance the accurate process of ACh release, which could be important to characterize molecules as a therapy for neuromuscular diseases in which neuromuscular crosstalk is impaired.

Background: Ketamine and psychedelics have abuse liability. They can also induce "transformative experiences" where individuals experience enhanced states of awareness. This enhanced awareness can lead to changes in preexisting behavioral patterns which could be beneficial in the treatment of substance use disorders (SUDs). Preclinical and clinical studies suggest that ketamine and psychedelics may alter markers associated with synaptic density, and that these changes may underlie effects such as sensitization, conditioned place preference, drug self-administration, and verbal memory performance. In this scoping review, we examined studies that measured synaptic markers in animals and humans after exposure to ketamine and/or psychedelics. Methods: A systematic search was conducted following PRISMA guidelines, through PubMed, EBSCO, Scopus, and Web of Science, based on a published protocol (Open Science Framework, DOI: 10.17605/OSF.IO/43FQ9). Both in vivo and in vitro studies were included. Studies on the following synaptic markers were included: dendritic structural changes, PSD-95, synapsin-1, synaptophysin-1, synaptotagmin-1, and SV2A. Results: Eighty-four studies were included in the final analyses. Seventy-one studies examined synaptic markers following ketamine treatment, nine examined psychedelics, and four examined both. Psychedelics included psilocybin/psilocin, lysergic acid diethylamide, N, N-dimethyltryptamine, 2,5-dimethoxy-4- iodoamphetamine, and ibogaine/noribogaine. Mixed findings regarding synaptic changes in the hippocampus and prefrontal cortex (PFC) have been reported when ketamine was administered in a single dose under basal conditions. Similar mixed findings were seen under basal conditions in studies that used repeated administration of ketamine. However, studies that examined animals during stressful conditions found that a single dose of ketamine counteracted stressrelated reductions in synaptic markers in the hippocampus and PFC. Repeated administration of ketamine also counteracted stress effects in the hippocampus. Psychedelics generally increased synaptic markers, but results were more consistently positive for certain agents. Conclusion: Ketamine and psychedelics can increase synaptic markers under certain conditions. Heterogeneous findings may relate to methodological differences, agents administered (or different formulations of the same agent), sex, and type of markers. Future studies could address seemingly mixed results by using meta-analytical approaches or study designs that more fully consider individual differences. [ABSTRACT FROM AUTHOR]

BackgroundKetamine and psychedelics have abuse liability. They can also induce “transformative experiences” where individuals experience enhanced states of awareness. This enhanced awareness can lead to changes in preexisting behavioral patterns which could be beneficial in the treatment of substance use disorders (SUDs). Preclinical and clinical studies suggest that ketamine and psychedelics may alter markers associated with synaptic density, and that these changes may underlie effects such as sensitization, conditioned place preference, drug self-administration, and verbal memory performance. In this scoping review, we examined studies that measured synaptic markers in animals and humans after exposure to ketamine and/or psychedelics.MethodsA systematic search was conducted following PRISMA guidelines, through PubMed, EBSCO, Scopus, and Web of Science, based on a published protocol (Open Science Framework, DOI: 10.17605/OSF.IO/43FQ9). Both in vivo and in vitro studies were included. Studies on the following synaptic markers were included: dendritic structural changes, PSD-95, synapsin-1, synaptophysin-1, synaptotagmin-1, and SV2A.ResultsEighty-four studies were included in the final analyses. Seventy-one studies examined synaptic markers following ketamine treatment, nine examined psychedelics, and four examined both. Psychedelics included psilocybin/psilocin, lysergic acid diethylamide, N,N-dimethyltryptamine, 2,5-dimethoxy-4-iodoamphetamine, and ibogaine/noribogaine. Mixed findings regarding synaptic changes in the hippocampus and prefrontal cortex (PFC) have been reported when ketamine was administered in a single dose under basal conditions. Similar mixed findings were seen under basal conditions in studies that used repeated administration of ketamine. However, studies that examined animals during stressful conditions found that a single dose of ketamine counteracted stress-related reductions in synaptic markers in the hippocampus and PFC. Repeated administration of ketamine also counteracted stress effects in the hippocampus. Psychedelics generally increased synaptic markers, but results were more consistently positive for certain agents.ConclusionKetamine and psychedelics can increase synaptic markers under certain conditions. Heterogeneous findings may relate to methodological differences, agents administered (or different formulations of the same agent), sex, and type of markers. Future studies could address seemingly mixed results by using meta-analytical approaches or study designs that more fully consider individual differences.

Background: Bidirectional communication between presynaptic and postsynaptic components contribute to the homeostasis of the synapse. In the neuromuscular synapse, the arrival of the nerve impulse at the presynaptic terminal triggers the molecular mechanisms associated with ACh release, which can be retrogradely regulated by the resulting muscle contraction. This retrograde regulation, however, has been poorly studied. At the neuromuscular junction (NMJ), protein kinase A (PKA) enhances neurotransmitter release, and the phosphorylation of the molecules of the release machinery including synaptosomal associated protein of 25 kDa (SNAP-25) and Synapsin-1 could be involved. Methods: Accordingly, to study the effect of synaptic retrograde regulation of the PKA subunits and its activity, we stimulated the rat phrenic nerve (1 Hz, 30 min) resulting or not in contraction (abolished by µ-conotoxin GIIIB). Changes in protein levels and phosphorylation were detected by western blotting and cytosol/membrane translocation by subcellular fractionation. Synapsin-1 was localized in the levator auris longus (LAL) muscle by immunohistochemistry. Results: Here we show that synaptic PKA Cβ subunit regulated by RIIβ or RIIα subunits controls activity-dependent phosphorylation of SNAP-25 and Synapsin-1, respectively. Muscle contraction retrogradely downregulates presynaptic activity-induced pSynapsin-1 S9 while that enhances pSNAP-25 T138. Both actions could coordinately contribute to decreasing the neurotransmitter release at the NMJ. Conclusion: This provides a molecular mechanism of the bidirectional communication between nerve terminals and muscle cells to balance the accurate process of ACh release, which could be important to characterize molecules as a therapy for neuromuscular diseases in which neuromuscular crosstalk is impaired. [ABSTRACT FROM AUTHOR]

• Axon growth of hippocampal neurons was interfered by MA exposure during pregnancy. • Prenatal MA exposure disrupted synaptogenesis in embryos and infantile mice. • Effects of prenatal MA treatment on BDNF-TrkB signaling pathway was transiently exhibited in early ages. • MA-induced alterations in neuronal development resulted in memory impairment in adolescent and adult mice. Synaptogenesis plays critical roles in learning and memory processes and is susceptible to substance abuse toxicity. The present study aimed to elucidate the long-lasting effects of prenatal methamphetamine exposure on synaptogenesis and learning and memory. The involvement of BDNF-TrkB signaling was also investigated. Pregnant mice (C57BL/6 JNc) were administered methamphetamine (5 mg/kg, s.c.) on gestation days 8−15. Primary hippocampal cultures were prepared from fetuses at gestational day 16.5 to study neuronal morphology and synaptogenesis. The expression of synaptic proteins, BDNF and TrkB receptor was determined in postnatal day 14 (PND14), adolescent and adult mice; memory tests were also conducted. MA exposure decreased axon length and diameter, and synaptic areas in the primary cultures. Presynaptic protein was decreased in the hippocampus of PND14 mice prenatally exposed to MA, while increases in postsynaptic protein (PSD-95) were found in MA-exposed adolescent and adult mice. BDNF expression was enhanced in the prefrontal cortex and striatum of MA-exposed PND14 mice. Memory impairment was observed in MA-exposed adolescent and adult mice compared to control mice. Prenatal MA exposure disrupted neuronal growth and synapse formation in the developing brain with only short-term interference of the BDNF-TrkB signaling pathway, resulting in the adaptation of postsynaptic neurons. Alterations in the developing brain and synaptogenesis lead to long-lasting learning and memory impairment. [ABSTRACT FROM AUTHOR]

Background and Purpose: A significant number of HIV‐1 patients on antiretroviral therapy develop HIV‐associated neurocognitive disorders (HAND). Evidence indicate that biological sex may regulate HAND pathogenesis, but the mechanisms remain unknown. We investigated synaptic mechanisms associated with sex differences in HAND, using the HIV‐1‐transgenic 26 (Tg26) mouse model. Experimental Approach Contextual‐ and cue‐dependent memories of male and female Tg26 mice and littermate wild type mice were assessed in a fear conditioning paradigm. Hippocampal electrophysiology, immunohistochemistry, western blot, qRT‐PCR and ELISA techniques were used to investigate cellular, synaptic and molecular impairments. Key Results: Cue‐dependent memory was unaltered in male and female Tg26 mice, when compared to wild type mice. Male, but not female, Tg26 mice showed deficits in contextual fear memory. Consistently, only male Tg26 mice showed depressed hippocampal basal synaptic transmission and impaired LTP induction in area CA1. These deficits in male Tg26 mice were independent of hippocampal neuronal loss and microglial activation but were associated with increased HIV‐1 long terminal repeat mRNA expression, reduced hippocampal synapsin‐1 protein, reduced BDNF mRNA and protein, reduced AMPA glutamate receptor (GluA1) phosphorylation levels and increased glycogen synthase kinase 3 (GSK3) activity. Importantly, selective GSK3 inhibition using 4‐benzyl‐2‐methyl‐1,2,4‐thiadiazolidine‐3,5‐dione increased levels of synapsin‐1, BDNF and phosphorylated‐GluA1 proteins, restored hippocampal basal synaptic transmission and LTP, and improved contextual fear memory in male Tg26 mice. Conclusion and Implications: Sex‐dependent impairments in contextual fear memory and synaptic plasticity in Tg26 mice are associated with increased GSK3 activity. This implicates GSK3 inhibition as a potential therapeutic strategy to improve cognition in HIV‐1 patients. [ABSTRACT FROM AUTHOR]

Quercetin is a polyphenol with multiple biological activities, and results of our preliminary study showed that it could shorten the immobility time of mice in the forced swimming test and tail suspending test. The aim of this study was to investigate its effects on the behavioral performance of lipopolysaccharide (LPS)-challenged rats and explore the potential mechanism. The results showed that intragastrical administration of quercetin (40 mg/kg) could improve the bodyweight gain of LPS-challenged rats, increase the saccharin preference index in the saccharin preference test and the novel arm preference index in the Y-maze, and decrease the immobility time in the FST. However, it showed no significant effect on the performance of LPS-challenged rats in the Morris water maze and the plasma concentrations of nesfatin-1, C-reactive protein (CRP), and IL-6. Results of western blot showed that the expression levels of BDNF, Copine 6, p-TrkB, and the triggering receptors expressed on myeloid cells (TREM) 1 were decreased in both the hippocampus and the prefrontal cortex (PFC) of LPS-challenged rats, while the expression of TREM2 was increased. The protein expression of synapsin-1 was decreased in the hippocampus without significant changes in the PFC. These imbalance protein expressions could be balanced by treatment with quercetin. The results suggested that quercetin could alleviate LPS-induced depression-like behaviors and impairment of learning and memory in rats, the mechanism of which might be involved with regulating the BDNF-related imbalance expression of Copine 6 and TREM1/2 in the hippocampus and the PFC.

Oxidative stress triggers a lethal cascade, leading to Parkinson’s disease by causing degeneration of dopaminergic neurons. In this study, eight antioxidants were screened for their neuroprotective effect on PC12 cells (pheochromocytoma cell line) under oxidative stress induced by salsolinol (OSibS). Hydroxytyrosol was found to be the strongest neuroprotective agent; it improved viability of PC12 cells by up to 81.69% under OSibS. Afterward, two synaptic vesicle proteins, synapsin-1 and septin-5, were screened for their neuroprotective role; the overexpression of synapsin-1 and the downregulation of septin-5 separately improved the viability of PC12 cells by up to 71.17% and 67.00%, respectively, compared to PC12 cells only treated with salsolinol (PoTwS) under OSibS. Subsequently, the PC12+syn++sep− cell line was constructed and pretreated with 100 µM hydroxytyrosol, which improved its cell viability by up to 99.03% and led to 14.71- and 6.37-fold reductions in the levels of MDA and H2O2, respectively, and 6.8-, 12.97-, 10.57-, and 7.57-fold increases in the activity of catalase, glutathione reductase, superoxide dismutase, and glutathione peroxidase, respectively, compared to PoTwS under OSibS. Finally, alcohol dehydrogenase-6 from Saccharomyces cerevisiae was expressed in PC12+syn++sep− cells to convert 3,4-dihydroxyphenylacetaldehyde (an endogenous neurotoxin) into hydroxytyrosol. The PC12+syn++sep−+ADH6+ cell line also led to 22.38- and 12.33-fold decreases in the production of MDA and H2O2, respectively, and 7.15-, 13.93-, 12.08-, and 8.11-fold improvements in the activity of catalase, glutathione reductase, superoxide dismutase, and glutathione peroxidase, respectively, compared to PoTwS under OSibS. Herein, we report the endogenous production of a powerful antioxidant, hydroxytyrosol, from 3,4-dihydroxyphenylacetaldehyde, and evaluate its synergistic neuroprotective effect, along with synapsin-1 and septin-5, on PC12 cells under OSibS.

Occupational and environmental exposure to vanadium has been associated with toxicities in reproductive, respiratory, and cardiovascular systems. The knowledge on whether and how vanadium exposure caused neurobehavioral changes remains incomplete. This study was designed to investigate the changes in learning and memory following drinking water exposure to vanadium, and to conduct the preliminary study on underlying mechanisms. Male Sprague-Dawley rats were exposed to vanadium dissolved in drinking water at the concentration of 0.0, 0.5, 1.0 and 2.0 g/L, as the control, low-, medium-, and high- dose groups, respectively, for 12 weeks. The results by the Morris water maze test showed that the time for the testing animal to find the platform in the high exposed group was increased by 82.9% and 49.7%, as compared to animals in control and low-dose groups ( p < 0.05). There were significantly fewer rats in the medium- and high- dose groups than in the control group who were capable of crossing the platform ( p < 0.05). Quantitation of vanadium by atomic absorption spectrophotometry revealed a significant dose-dependent accumulation of vanadium in striatum ( r = 0.931, p < 0.01). Histopathological examination further demonstrated a degenerative damage in vanadium-exposed striatum. Interestingly, with the increase of the dose of vanadium, the contents of neurotransmitter ACh, 5-HT and GABA in the striatum increased; however, the levels of Syn1 was significantly reduced in the exposed groups compared with controls ( p < 0.05). These data suggest that vanadium exposure apparently reduces the animals’ learning ability. This could be due partly to vanadium’s accumulation in striatum and the ensuing toxicity to striatal structure and synaptic plasticity. Further research is warranted for mechanistic understanding of vanadium-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

Postchemotherapy cognitive impairment (PCCI) is commonly exhibited by cancer patients treated with a variety of chemotherapeutic agents, including the endocrine disruptor tamoxifen (TAM). The etiology of PCCI is poorly understood. Our goal was to develop high-throughput assay methods to test the effects of chemicals on neuronal function applicable to PCCI. Rat hippocampal neurons (RHNs) were plated in 96- or 384-well dishes and exposed to test compounds (forskolin [FSK], 17β-estradiol [ES]), TAM or fulvestrant [FUL], aka ICI 182,780) for 6-14 days. Kinetic Image Cytometry™ (KIC™) methods were developed to quantify spontaneously occurring intracellular calcium transients representing the activity of the neurons, and high-content analysis (HCA) methods were developed to quantify the expression, colocalization, and puncta formed by synaptic proteins (postsynaptic density protein-95 [PSD-95] and presynaptic protein Synapsin-1 [Syn-1]). As quantified by KIC, FSK increased the occurrence and synchronization of the calcium transients indicating stimulatory effects on RHN activity, whereas TAM had inhibitory effects. As quantified by HCA, FSK also increased PSD-95 puncta and PSD-95:Syn-1 colocalization, whereas ES increased the puncta of both PSD-95 and Syn-1 with little effect on colocalization. The estrogen receptor antagonist FUL also increased PSD-95 puncta. In contrast, TAM reduced Syn-1 and PSD-95:Syn-1 colocalization, consistent with its inhibitory effects on the calcium transients. Thus TAM reduced activity and synapse formation by the RHNs, which may relate to the ability of this agent to cause PCCI. The results illustrate that KIC and HCA can be used to quantify neurotoxic and neuroprotective effects of chemicals in RHNs to investigate mechanisms and potential therapeutics for PCCI. [ABSTRACT FROM AUTHOR]

Transcranial low-level laser (light) therapy (LLLT) is a new non-invasive approach to treating a range of brain disorders including traumatic brain injury (TBI). We (and others) have shown that applying near-infrared light to the head of animals that have suffered TBI produces improvement in neurological functioning, lessens the size of the brain lesion, reduces neuroinflammation, and stimulates the formation of new neurons. In the present study we used a controlled cortical impact TBI in mice and treated the mice either once (4 h post-TBI, 1-laser), or three daily applications (3-laser) with 810 nm CW laser 36 J/cm2 at 50 mW/cm2. Similar to previous studies, the neurological severity score improved in laser-treated mice compared to untreated TBI mice at day 14 and continued to further improve at days 21 and 28 with 3-laser being better than 1-laser. Mice were sacrificed at days 7 and 28 and brains removed for immunofluorescence analysis. Brain-derived neurotrophic factor (BDNF) was significantly upregulated by laser treatment in the dentate gyrus of the hippocampus (DG) and the subventricular zone (SVZ) but not in the perilesional cortex (lesion) at day 7 but not at day 28. Synapsin-1 (a marker for synaptogenesis, the formation of new connections between existing neurons) was significantly upregulated in lesion and SVZ but not DG, at 28 days but not 7 days. The data suggest that the benefit of LLLT to the brain is partly mediated by stimulation of BDNF production, which may in turn encourage synaptogenesis. Moreover the pleiotropic benefits of BDNF in the brain suggest LLLT may have wider applications to neurodegenerative and psychiatric disorders. [ABSTRACT FROM AUTHOR]

Neuroendocrine (NE)-like tumors secrete various signaling molecules to establish paracrine communication within the tumor milieu and to create a therapy-resistant environment. It is important to identify molecular mediators that regulate this secretory phenotype in NE-like cancer. The current study highlights the importance of a cell surface molecule, Neuropilin-2 (NRP2), for the secretory function of NE-like prostate cancer (PCa). Our analysis on different patient cohorts suggests that NRP2 is high in NE-like PCa. We have developed cell line models to investigate NRP2's role in NE-like PCa. Our bioinformatics, mass spectrometry, cytokine array, and other supporting experiments reveal that NRP2 regulates robust secretory phenotype in NE-like PCa and controls the secretion of factors promoting cancer cell survival. Depletion of NRP2 reduces the secretion of these factors and makes resistant cancer cells sensitive to chemotherapy in vitro and in vivo. Therefore, targeting NRP2 can revert cellular secretion and sensitize PCa cells toward therapy. [Display omitted] • NRP2 is highly expressed in NE-like prostate cancer • NRP2 regulates the fusion of secretory vesicles to plasma membrane • The secretion of several cytokines, including IL-8, is regulated by NRP2 • NRP2-depletion from NE-like cells sensitizes adjacent adenocarcinoma to chemotherapy Islam et al. observe high expression of a cell surface receptor, neuropilin-2 (NRP2), in neuroendocrine-like prostate cancer. NRP2 regulates the secretion of cytokines by facilitating the fusion of secretory vesicles to cell membrane. The secretory products protect not only the neuroendocrine cells but also the adjacent adenocarcinoma from chemotherapies. [ABSTRACT FROM AUTHOR]

Abstract: Pregnant rats (starting on E5) were exposed chronically to carbon monoxide (CO) from gestational days 5–20. In the postnatal period, rat pups were grouped as follows: group A: prenatal exposure to CO only; group B: prenatal exposure to CO then exposed to CO from postnatal day (P) 5 to P20; group C, control (air without CO). Groups A and B showed similar deleterious effects after CO exposure. At P3, rat pup cochlea from group A showed a normal organization of the organ of Corti. There was no morphological deterioration, or loss of inner or outer hair cells. At P20, animals from group A and B showed vacuolization on the afferent terminals at the basal portion of the cochlea. We found synapsin-1 immunoreactivity (IR) to be decreased in efferent nerve terminals in CO-exposed pups at P3. From P12 to P20, synapsin-1-IR is low in efferent terminals. At P20, type I spiral ganglia neurons and afferent nerve fibers showed decreased neurofilament-IR in CO-exposed groups when compared with controls. Heme oxygenase-1 and superoxide dismutase-1-IR were elevated in the stria vascularis and blood vessels from CO-exposed rat pups at P12 and P20 in group B; in contrast group A showed a comparable expression to controls. Inducible nitric oxide synthase (iNOS) and nitrotyrosine-IR were increased in blood vessels of the cochlea in CO-exposed groups, from P3 to P20. iNOS up-regulation and the presence of nitrotyrosine in blood vessels of the cochlea indicated that CO exposure activates the production of nitric oxide via increased iNOS activity. Prenatal chronic CO exposure promotes oxidative stress in the cochlea blood vessels that in turn is reflected in damage to spiral ganglia neurons and inner hair cells, suggesting for the first time that prenatal exposure to CO at concentrations expected in poorly ventilated environments impairs the development of the inner ear. [Copyright &y& Elsevier]

Keywords: quercetin; nesfatin-1; brain derived neurotrophic factor (BDNF); Copine 6; the triggering receptors expressed on myeloid cells (TREMs); synapsin-1 EN quercetin nesfatin-1 brain derived neurotrophic factor (BDNF) Copine 6 the triggering receptors expressed on myeloid cells (TREMs) synapsin-1 1 1 1 04/17/20 20200415 NES 200415 An author name was incorrectly spelled as "Fang Ke." Quercetin, nesfatin-1, brain derived neurotrophic factor (BDNF), Copine 6, the triggering receptors expressed on myeloid cells (TREMs), synapsin-1. [Extracted from the article]

Oxidative stress triggers a lethal cascade, leading to Parkinson's disease by causing degeneration of dopaminergic neurons. In this study, eight antioxidants were screened for their neuroprotective effect on PC12 cells (pheochromocytoma cell line) under oxidative stress induced by salsolinol (OSibS). Hydroxytyrosol was found to be the strongest neuroprotective agent; it improved viability of PC12 cells by up to 81.69% under OSibS. Afterward, two synaptic vesicle proteins, synapsin-1 and septin-5, were screened for their neuroprotective role; the overexpression of synapsin-1 and the downregulation of septin-5 separately improved the viability of PC12 cells by up to 71.17% and 67.00%, respectively, compared to PC12 cells only treated with salsolinol (PoTwS) under OSibS. Subsequently, the PC12+syn++sep− cell line was constructed and pretreated with 100 µM hydroxytyrosol, which improved its cell viability by up to 99.03% and led to 14.71- and 6.37-fold reductions in the levels of MDA and H2O2, respectively, and 6.8-, 12.97-, 10.57-, and 7.57-fold increases in the activity of catalase, glutathione reductase, superoxide dismutase, and glutathione peroxidase, respectively, compared to PoTwS under OSibS. Finally, alcohol dehydrogenase-6 from Saccharomyces cerevisiae was expressed in PC12+syn++sep− cells to convert 3,4-dihydroxyphenylacetaldehyde (an endogenous neurotoxin) into hydroxytyrosol. The PC12+syn++sep−+ADH6+ cell line also led to 22.38- and 12.33-fold decreases in the production of MDA and H2O2, respectively, and 7.15-, 13.93-, 12.08-, and 8.11-fold improvements in the activity of catalase, glutathione reductase, superoxide dismutase, and glutathione peroxidase, respectively, compared to PoTwS under OSibS. Herein, we report the endogenous production of a powerful antioxidant, hydroxytyrosol, from 3,4-dihydroxyphenylacetaldehyde, and evaluate its synergistic neuroprotective effect, along with synapsin-1 and septin-5, on PC12 cells under OSibS. [ABSTRACT FROM AUTHOR]

Aggregation of immuno-proteomic data reveals that i) herpesviruses and synaptic proteins –in particular Synapsin-1 and Bassoon - share a large number of hexapeptides that also recur in hundreds of epitopes experimentally validated as immunopositive in the human host, and ii) the shared peptides are also spread among human epilepsy-related proteins. The data indicate that cross-reactive processes may be associated with pathogenetic mechanisms in epilepsy, thus suggesting a role of autoimmunity in etiopathology of epilepsies after herpesvirus-infections. • Herpesviruses and synaptic proteins related to epilepsy share a high number of hexapeptide sequences. • The peptide sharing mainly involves the synaptic proteins Synapsin-1 and Bassoon. • The shared peptides are also part of immunopositive epitopes, thus suggesting cross-reactivity as a causal mechanism that connects herpesviral infections to epilepsies. • On the whole, the data support the concept of epilepsy as an autoimmune disease [ABSTRACT FROM AUTHOR]

Neuromodulators bind to pre- and postsynaptic G protein-coupled receptors (GPCRs), are able to quickly change intracellular cyclic AMP (cAMP) and Ca 2+ levels, and are thought to play important roles in neuropsychiatric and neurodegenerative diseases. Here, we discovered in human neurons an unanticipated presynaptic mechanism that acutely changes synaptic ultrastructure and regulates synaptic communication. Activation of neuromodulator receptors bidirectionally controlled synaptic vesicle numbers within nerve terminals. This control correlated with changes in the levels of cAMP-dependent protein kinase A-mediated phosphorylation of synapsin-1. Using a conditional deletion approach, we reveal that the neuromodulator-induced control of synaptic vesicle numbers was largely dependent on synapsin-1. We propose a mechanism whereby non-phosphorylated synapsin-1 "latches" synaptic vesicles to presynaptic clusters at the active zone. cAMP-dependent phosphorylation of synapsin-1 then removes the vesicles. cAMP-independent dephosphorylation of synapsin-1 in turn recruits vesicles. Synapsin-1 thereby bidirectionally regulates synaptic vesicle numbers and modifies presynaptic neurotransmitter release as an effector of neuromodulator signaling in human neurons., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Development of an optogenetically controllable human neural network model in three-dimensional (3D) cultures can provide an investigative system that is more physiologically relevant and better able to mimic aspects of human brain function. Light-sensitive neurons were generated by transducing channelrhodopsin-2 (ChR2) into human induced pluripotent stem cell (hiPSC) derived neural progenitor cells (Axol) using lentiviruses and cell-type specific promoters. A mixed population of human iPSC-derived cortical neurons, astrocytes and progenitor cells were obtained (Axol-ChR2) upon neural differentiation. Pan-neuronal promoter synapsin-1 (SYN1) and excitatory neuron-specific promoter calcium-calmodulin kinase II (CaMKII) were used to drive reporter gene expression in order to assess the differentiation status of the targeted cells. Expression of ChR2 and characterisation of subpopulations in differentiated Axol-ChR2 cells were evaluated using flow cytometry and immunofluorescent staining. These cells were transferred from 2D culture to 3D alginate hydrogel functionalised with arginine-glycine-aspartate (RGD) and small molecules (Y-27632). Improved RGD-alginate hydrogel was physically characterised and assessed for cell viability to serve as a generic 3D culture system for human pluripotent stem cells (hPSCs) and neuronal cells. Prior to cell encapsulation, neural network activities of Axol-ChR2 cells and primary neurons were investigated using calcium imaging. Results demonstrate that functional activities were successfully achieved through expression of ChR2- by both the CaMKII and SYN1 promoters. The RGD-alginate hydrogel system supports the growth of differentiated Axol-ChR2 cells whilst allowing detection of ChR2 expression upon light stimulation. This allows precise and non-invasive control of human neural networks in 3D., (© 2018 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.)