The Memory Orchestra: Contribution of Astrocytes / 神经科学通报·英文版

For decades, memory research has centered on the role of neurons, which do not function in isolation. However, astrocytes play important roles in regulating neuronal recruitment and function at the local and network levels, forming the basis for information processing as well as memory formation and storage. In this review, we discuss the role of astrocytes in memory functions and their cellular underpinnings at multiple time points. We summarize important breakthroughs and controversies in the field as well as potential avenues to further illuminate the role of astrocytes in memory processes.

The Structure and Function of Glial Networks: Beyond the Neuronal Connections / 神经科学通报·英文版

Glial cells, consisting of astrocytes, oligodendrocyte lineage cells, and microglia, account for >50% of the total number of cells in the mammalian brain. They play key roles in the modulation of various brain activities under physiological and pathological conditions. Although the typical morphological features and characteristic functions of these cells are well described, the organization of interconnections of the different glial cell populations and their impact on the healthy and diseased brain is not completely understood. Understanding these processes remains a profound challenge. Accumulating evidence suggests that glial cells can form highly complex interconnections with each other. The astroglial network has been well described. Oligodendrocytes and microglia may also contribute to the formation of glial networks under various circumstances. In this review, we discuss the structure and function of glial networks and their pathological relevance to central nervous system diseases. We also highlight opportunities for future research on the glial connectome.

Roles of NG2 Glia in Cerebral Small Vessel Disease / 神经科学通报·英文版

Cerebral small vessel disease (CSVD) is one of the most prevalent pathologic processes affecting 5% of people over 50 years of age and contributing to 45% of dementia cases. Increasing evidence has demonstrated the pathological roles of chronic hypoperfusion, impaired cerebral vascular reactivity, and leakage of the blood-brain barrier in CSVD. However, the pathogenesis of CSVD remains elusive thus far, and no radical treatment has been developed. NG2 glia, also known as oligodendrocyte precursor cells, are the fourth type of glial cell in addition to astrocytes, microglia, and oligodendrocytes in the mammalian central nervous system. Many novel functions for NG2 glia in physiological and pathological states have recently been revealed. In this review, we discuss the role of NG2 glia in CSVD and the underlying mechanisms.

Astrocytes in Chronic Pain: Cellular and Molecular Mechanisms / 神经科学通报·英文版

Chronic pain is challenging to treat due to the limited therapeutic options and adverse side-effects of therapies. Astrocytes are the most abundant glial cells in the central nervous system and play important roles in different pathological conditions, including chronic pain. Astrocytes regulate nociceptive synaptic transmission and network function via neuron-glia and glia-glia interactions to exaggerate pain signals under chronic pain conditions. It is also becoming clear that astrocytes play active roles in brain regions important for the emotional and memory-related aspects of chronic pain. Therefore, this review presents our current understanding of the roles of astrocytes in chronic pain, how they regulate nociceptive responses, and their cellular and molecular mechanisms of action.

Interactions Between Astrocytes and Oligodendroglia in Myelin Development and Related Brain Diseases / 神经科学通报·英文版

Astrocytes (ASTs) and oligodendroglial lineage cells (OLGs) are major macroglial cells in the central nervous system. ASTs communicate with each other through connexin (Cx) and Cx-based network structures, both of which allow for quick transport of nutrients and signals. Moreover, ASTs interact with OLGs through connexin (Cx)-mediated networks to modulate various physiological processes in the brain. In this article, following a brief description of the infrastructural basis of the glial networks and exocrine factors by which ASTs and OLGs may crosstalk, we focus on recapitulating how the interactions between these two types of glial cells modulate myelination, and how the AST-OLG interactions are involved in protecting the integrity of the blood-brain barrier (BBB) and regulating synaptogenesis and neural activity. Recent studies further suggest that AST-OLG interactions are associated with myelin-related diseases, such as multiple sclerosis. A better understanding of the regulatory mechanisms underlying AST-OLG interactions may inspire the development of novel therapeutic strategies for related brain diseases.

Immunological Markers for Central Nervous System Glia / 神经科学通报·英文版

Glial cells in the central nervous system (CNS) are composed of oligodendrocytes, astrocytes and microglia. They contribute more than half of the total cells of the CNS, and are essential for neural development and functioning. Studies on the fate specification, differentiation, and functional diversification of glial cells mainly rely on the proper use of cell- or stage-specific molecular markers. However, as cellular markers often exhibit different specificity and sensitivity, careful consideration must be given prior to their application to avoid possible confusion. Here, we provide an updated overview of a list of well-established immunological markers for the labeling of central glia, and discuss the cell-type specificity and stage dependency of their expression.

Spatiotemporal Dynamics of the Molecular Expression Pattern and Intercellular Interactions in the Glial Scar Response to Spinal Cord Injury / 神经科学通报·英文版

Nerve regeneration in adult mammalian spinal cord is poor because of the lack of intrinsic regeneration of neurons and extrinsic factors - the glial scar is triggered by injury and inhibits or promotes regeneration. Recent technological advances in spatial transcriptomics (ST) provide a unique opportunity to decipher most genes systematically throughout scar formation, which remains poorly understood. Here, we first constructed the tissue-wide gene expression patterns of mouse spinal cords over the course of scar formation using ST after spinal cord injury from 32 samples. Locally, we profiled gene expression gradients from the leading edge to the core of the scar areas to further understand the scar microenvironment, such as neurotransmitter disorders, activation of the pro-inflammatory response, neurotoxic saturated lipids, angiogenesis, obstructed axon extension, and extracellular structure re-organization. In addition, we described 21 cell transcriptional states during scar formation and delineated the origins, functional diversity, and possible trajectories of subpopulations of fibroblasts, glia, and immune cells. Specifically, we found some regulators in special cell types, such as Thbs1 and Col1a2 in macrophages, CD36 and Postn in fibroblasts, Plxnb2 and Nxpe3 in microglia, Clu in astrocytes, and CD74 in oligodendrocytes. Furthermore, salvianolic acid B, a blood-brain barrier permeation and CD36 inhibitor, was administered after surgery and found to remedy fibrosis. Subsequently, we described the extent of the scar boundary and profiled the bidirectional ligand-receptor interactions at the neighboring cluster boundary, contributing to maintain scar architecture during gliosis and fibrosis, and found that GPR37L1_PSAP, and GPR37_PSAP were the most significant gene-pairs among microglia, fibroblasts, and astrocytes. Last, we quantified the fraction of scar-resident cells and proposed four possible phases of scar formation: macrophage infiltration, proliferation and differentiation of scar-resident cells, scar emergence, and scar stationary. Together, these profiles delineated the spatial heterogeneity of the scar, confirmed the previous concepts about scar architecture, provided some new clues for scar formation, and served as a valuable resource for the treatment of central nervous system injury.

Clinical features of autoimmune glial fibrillary acidic protein astrocytopathy in children: an analysis of 34 cases / 中国当代儿科杂志

OBJECTIVES@#To study the clinical features of children with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A).@*METHODS@#A retrospective analysis was performed on the medical data of 34 children with GFAP-A who attended the Department of Neurology, Children's Hospital of Chongqing Medical University, from January 2020 to February 2022. The medical data included clinical manifestations, cerebrospinal fluid features, imaging examination results, treatment, and prognosis.@*RESULTS@#The median age of onset was 8.4 (range 1.9-14.9) years for the 34 children with GFAP-A. The main clinical manifestations included headache (50%, 17/34), fever (47%, 16/34), visual impairment (47%, 16/34), and disturbance of consciousness (44%, 15/34). Abnormal cerebrospinal fluid results were observed in 19 children (56%, 19/34), among whom 8 children had positive autoantibody. The children with overlap syndrome had significantly higher recurrence rate and rate of use of immunosuppressant than those without overlap syndrome (P<0.05). About 77% (24/31) of the children had good response to immunotherapy, and only 1 child had poor prognosis.@*CONCLUSIONS@#Children with GFAP-A often have non-specific clinical symptoms and show good response to immunotherapy. Children with overlap syndrome have a high recurrence rate, and early application of immunosuppressants may help to prevent recurrence and alleviate symptoms.

Os impactos da neuroinflamação na doença de Alzheimer / The impacts of neuroinflamation on Alzheimer's disease

A Doença de Alzheimer (DA) consiste em um grande problema de saúde pública no Brasil e no mundo. Trata-se de uma doença neurodegenerativa, em que ocorre perda progressiva de neurônios e atrofia das regiões cerebrais. Essa degeneração está associada principalmente ao depósito de duas proteínas tóxicas: a proteína beta-amiloide e a proteína Tau, uma vez que estas proteínas se encontram acumuladas, elas prejudicam a ocorrência de sinapses nervosas. Apesar de extremamente prevalente na população mais idosa, suas causas ainda não estão bem esclarecidas, sendo que vários fatores já foram apontados como possíveis motivos para o surgimento do depósito destas proteínas, levando assim a neurodegeneração. Recentemente, tem se estudado o papel da inflamação, que é fundamental durante todo o curso da doença, tanto para a eliminação das proteínas tóxicas quanto para a proteção de neurônios. Um funcionamento anormal do processo inflamatório poderia dificultar a eliminação das proteínas e acentuar a perda neuronal. Com isso essa revisão de literatura tem como objetivo descrever os principais fatores imunológico que se encontram alterados na Doença de Alzheimer e como isso pode contribuir para o quadro neurodegenerativo.

Alzheimer's Disease (AD) is a major public health problem in Brazil and worldwide. It is a neurodegenerative disease, in which there is a progressive loss of neurons and atrophy of brain regions. This degeneration is mainly associated with the deposition of two toxic proteins, the beta-amyloid protein and the Tau protein, once these proteins are accumulated, they impair the occurrence of nerve synapses. Despite being extremely prevalent in the older population, its causes are still not well understood, and several factors have already been pointed out as possible reasons for the emergence of the deposit of these proteins, thus leading to neurodegeneration. Recently, the role of inflammation, which is fundamental throughout the course of the disease, has been studied, both for the elimination of toxic proteins and for the protection of neurons. An abnormal functioning of the inflammatory process could hinder the elimination of proteins and accentuate the neuronal loss Thus, this literature review aims to describe the main immunological factors that are altered in Alzheimer's Disease and how this can contribute to the neurodegenerative picture.

Targeting GATA1 and p2x7r Locus Binding in Spinal Astrocytes Suppresses Chronic Visceral Pain by Promoting DNA Demethylation / 神经科学通报·英文版

Irritable bowel syndrome is a gastrointestinal disorder of unknown etiology characterized by widespread, chronic abdominal pain associated with altered bowel movements. Increasing amounts of evidence indicate that injury and inflammation during the neonatal period have long-term effects on tissue structure and function in the adult that may predispose to gastrointestinal diseases. In this study we aimed to investigate how the epigenetic regulation of DNA demethylation of the p2x7r locus guided by the transcription factor GATA binding protein 1 (GATA1) in spinal astrocytes affects chronic visceral pain in adult rats with neonatal colonic inflammation (NCI). The spinal GATA1 targeting to DNA demethylation of p2x7r locus in these rats was assessed by assessing GATA1 function with luciferase assay, chromatin immunoprecipitation, patch clamp, and interference in vitro and in vivo. In addition, a decoy oligodeoxynucleotide was designed and applied to determine the influence of GATA1 on the DNA methylation of a p2x7r CpG island. We showed that NCI caused the induction of GATA1, Ten-eleven translocation 3 (TET3), and purinergic receptors (P2X7Rs) in astrocytes of the spinal dorsal horn, and demonstrated that inhibiting these molecules markedly increased the pain threshold, inhibited the activation of astrocytes, and decreased the spinal sEPSC frequency. NCI also markedly demethylated the p2x7r locus in a manner dependent on the enhancement of both a GATA1-TET3 physical interaction and GATA1 binding at the p2x7r promoter. Importantly, we showed that demethylation of the p2x7r locus (and the attendant increase in P2X7R expression) was reversed upon knockdown of GATA1 or TET3 expression, and demonstrated that a decoy oligodeoxynucleotide that selectively blocked the GATA1 binding site increased the methylation of a CpG island in the p2x7r promoter. These results demonstrate that chronic visceral pain is mediated synergistically by GATA1 and TET3 via a DNA-demethylation mechanism that controls p2x7r transcription in spinal dorsal horn astrocytes, and provide a potential therapeutic strategy by targeting GATA1 and p2x7r locus binding.

Entrainment of Astrocytic and Neuronal Ca2+ Population Dynamics During Information Processing of Working Memory in Mice / 神经科学通报·英文版

Astrocytes are increasingly recognized to play an active role in learning and memory, but whether neural inputs can trigger event-specific astrocytic Ca2+ dynamics in real time to participate in working memory remains unclear due to the difficulties in directly monitoring astrocytic Ca2+ dynamics in animals performing tasks. Here, using fiber photometry, we showed that population astrocytic Ca2+ dynamics in the hippocampus were gated by sensory inputs (centered at the turning point of the T-maze) and modified by the reward delivery during the encoding and retrieval phases. Notably, there was a strong inter-locked and antagonistic relationship between the astrocytic and neuronal Ca2+ dynamics with a 3-s phase difference. Furthermore, there was a robust synchronization of astrocytic Ca2+ at the population level among the hippocampus, medial prefrontal cortex, and striatum. The inter-locked, bidirectional communication between astrocytes and neurons at the population level may contribute to the modulation of information processing in working memory.

Developmental Origins of Human Cortical Oligodendrocytes and Astrocytes / 神经科学通报·英文版

Human cortical radial glial cells are primary neural stem cells that give rise to cortical glutaminergic projection pyramidal neurons, glial cells (oligodendrocytes and astrocytes) and olfactory bulb GABAergic interneurons. One of prominent features of the human cortex is enriched with glial cells, but there are major gaps in understanding how these glial cells are generated. Herein, by integrating analysis of published human cortical single-cell RNA-Seq datasets with our immunohistochemistical analyses, we show that around gestational week 18, EGFR-expressing human cortical truncated radial glial cells (tRGs) give rise to basal multipotent intermediate progenitors (bMIPCs) that express EGFR, ASCL1, OLIG2 and OLIG1. These bMIPCs undergo several rounds of mitosis and generate cortical oligodendrocytes, astrocytes and olfactory bulb interneurons. We also characterized molecular features of the cortical tRG. Integration of our findings suggests a general picture of the lineage progression of cortical radial glial cells, a fundamental process of the developing human cerebral cortex.

Baicalin treats cerebral ischemia reperfusion-induced brain edema in rats by inhibiting TRPV4 and AQP4 of astrocytes / 中国中药杂志

This study aims to explore the pharmacodynamic effect of baicalin on rat brain edema induced by cerebral ischemia reperfusion injury and discuss the mechanism from the perspective of inhibiting astrocyte swelling, which is expected to serve as a refe-rence for the treatment of cerebral ischemia with Chinese medicine. To be specific, middle cerebral artery occlusion(suture method) was used to induce cerebral ischemia in rats. Rats were randomized into normal group, model group, high-dose baicalin(20 mg·kg~(-1)) group, and low-dose baicalin(10 mg·kg~(-1)) group. The neurobehavior, brain index, brain water content, and cerebral infarction area of rats were measured 6 h and 24 h after cerebral ischemia. Brain slices were stained with hematoxylin and eosin(HE) for the observation of pathological morphology of cerebral cortex after baicalin treatment. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the content of total L-glutathione(GSH) and glutamic acid(Glu) in brain tissue, Western blot to measure the content of glial fibrillary acidic protein(GFAP), aquaporin-4(AQP4), and transient receptor potential vanilloid type 4(TRPV4), and immunohistochemical staining to observe the expression of GFAP. The low-dose baicalin was used for exploring the mechanism. The experimental results showed that the neurobehavioral scores(6 h and 24 h of cerebral ischemia), brain water content, and cerebral infarction area of the model group were increased, and both high-dose and low-dose baicalin can lower the above three indexes. The content of GSH dropped but the content of Glu raised in brain tissue of rats in the model group. Low-dose baicalin can elevate the content of GSH and lower the content of Glu. According to the immunohistochemical staining result, the model group demonstrated the increase in GFAP expression, and swelling and proliferation of astrocytes, and the low-dose baicalin can significantly improve this situation. The results of Western blot showed that the expression of GFAP, TRPV4, and AQP4 in the cerebral cortex of the model group increased, and the low-dose baicalin reduce their expression. The cerebral cortex of rats in the model group was severely damaged, and the low-dose baicalin can significantly alleviate the damage. The above results indicate that baicalin can effectively relieve the brain edema caused by cerebral ischemia reperfusion injury in rats, possibly by suppressing astrocyte swelling and TRPV4 and AQP4.

Rol de la neuroglia en el trastorno del espectro autista / Role of neuroglia in autism spectrum disorder

RESUMEN: El trastorno del espectro autista (TEA) se caracteriza por presentar déficits persistentes en la comunicación y en la interacción social. Además, patrones de comportamiento, intereses o actividades de tipo restrictivo o repetitivo. Su etiología es compleja y heterogenia, y los mecanismos neurobiológicos que dan lugar al fenotipo clínico aún no se conocen por completo. Las investigaciones apuntan a factores genéticos y ambientales que afectan el cerebro en desarrollo. Estos avances coinciden con un aumento en la comprensión de las funciones fisiológicas y el potencial patológico de la neuroglia en el sistema nervioso central (SNC) que llevó a la noción de la contribución fundamental de estas células en el TEA. Así, el objetivo de este artículo fue revisar brevemente los factores de riesgo clave asociados al TEA y luego, explorar la contribución de la neuroglia en este trastorno. Se destaca el rol de los astrocitos, los microglocitos y los oligodendrocitos en el control homeostático del SNC, en la regulación inmunitaria del cerebro y en la mielinización axonal, así como el mal funcionamiento y las alteraciones morfológicas de estas células en los cerebros autistas.

SUMMARY: Autism spectrum disorder (ASD) is characterized by persistent deficits in communication and social interaction, as well as restrictive or repetitive activities or interests. Its etiology is complex and heterogeneous, and the neurobiological mechanisms that give rise to the clinical phenotype are not yet fully understood. Research points to genetic and environmental factors that affect the developing brain. These advances are consistent with an enhanced understanding of the physiological functions and pathological potential of neuroglia in the central nervous system (CNS) which supports the conclusion of the contribution of these cells in ASD. Therefore, the objective of this article was to briefly review the key risk factors associated with ASD and then explore the contribution of glia in this disorder. The role of astrocytes, microgliocytes and oligodendrocytes in the homeostatic control of the CNS in the immune regulation of the brain and in axonal myelination, as well as malfunction and morphological alterations of these cells in autistic brains are emphasized.

Active lifestyle enhances protein expression profile in subjects with Lewy body pathology / O estilo de vida ativo melhora o perfil de expressão de proteínas em indivíduos com a patologia de corpos de lewy

ABSTRACT. Clinical trials of the effects of physical activity have reported improvements in symptoms and quality of life in patients with Parkinson's disease (PD). Additionally, morphological brain changes after exercising were reported in PD animal models. However, these lifestyle-related changes were not evaluated in postmortem brain tissue. Objective: We aimed to evaluate, by immunohistochemistry, astrocytes, tyrosine hydroxylase (TH) and structural proteins expression (neurofilaments and microtubules — MAP2) changes in postmortem brain samples of individuals with Lewy body pathology. Methods: Braak PD stage≥III samples, classified by neuropathology analysis, from The Biobank for Aging Studies were classified into active (n=12) and non-active (n=12) groups, according to physical activity lifestyle, and paired by age, sex and Braak staging. Substantia nigra and basal ganglia were evaluated. Results: Groups were not different in terms of age or gender and had similar PD neuropathological burden (p=1.00). We observed higher TH expression in the active group in the substantia nigra and the basal ganglia (p=0.04). Astrocytes was greater in the non-active subjects in the midbrain (p=0.03) and basal ganglia (p=0.0004). MAP2 levels were higher for non-active participants in the basal ganglia (p=0.003) and similar between groups in the substantia nigra (p=0.46). Neurofilament levels for non-active participants were higher in the substantia nigra (p=0.006) but not in the basal ganglia (p=0.24). Conclusion: Active lifestyle seems to promote positive effects on brain by maintaining dopamine synthesis and structural protein expression in the nigrostriatal system and decrease astrogliosis in subjects with the same PD neuropathology burden.

RESUMO. Estudos dos efeitos da atividade física relataram melhora nos sintomas e na qualidade de vida de pacientes com doença de Parkinson (DP). Além disso, alterações morfológicas do cérebro após o exercício físico foram relatadas em modelos animais da DP. No entanto, essas mudanças relacionadas ao estilo de vida não foram avaliadas em tecido cerebral post-mortem. Objetivo: Avaliar a expressão de astrócitos, tirosina hidroxilase (TH) e a expressão de proteínas estruturais (neurofilamentos e microtúbulos — MAP2) por imuno-histoquímica, em amostras cerebrais post-mortem de indivíduos com corpos de Lewy. Métodos: Amostras com estágio de Braak para DP≥III, classificação neuropatológica, fornecidas pelo biobanco de estudos do envelhecimento foram classificadas em grupos ativos (n=12) e não ativos (n=12), de acordo com o estilo de vida (atividade física), e pareados por idade, sexo e estadiamento de Braak. Analisou-se a substância negra e gânglios da base. Resultados: Idade, sexo e classificação para DP foram semelhantes (p=1,00). Observou-se maior expressão de TH no grupo ativo (p=0,04). Amostras de não ativos revelaram maior expressão de astrócitos no mesencéfalo (p=0,03) e nos gânglios da base (p=0,0004); MAP2 nos gânglios da base (p=0,003); os níveis de neurofilamentos foram maiores na substância negra (p=0,006). Conclusão: O estilo de vida ativo parece promover efeitos positivos no cérebro, mantendo a síntese de dopamina e a expressão estrutural de proteínas no sistema nigrostriatal e com diminuição da ativação de astrócitos em indivíduos com a mesma classificação neuropatológica para a DP.

Rapid and long-lasting antidepressant-like effects of ketamine and their relationship with the expression of brain enzymes, BDNF, and astrocytes

Ketamine (KET) is an N-methyl-D-aspartate (NMDA) antagonist with rapid and long-lasting antidepressant effects, but how the drug shows its sustained effects is still a matter of controversy. The objectives were to evaluate the mechanisms for KET rapid (30 min) and long-lasting (15 and 30 days after) antidepressant effects in mice. A single dose of KET (2, 5, or 10 mg/kg, po) was administered to male Swiss mice and the forced swim test (FST) was performed 30 min, 15, or 30 days later. Imipramine (IMI, 30 mg/kg, ip), a tricyclic antidepressant drug, was used as reference. The mice were euthanized, separated into two time-point groups (D1, first day after KET injection; D30, 30 days later), and brain sections were processed for glycogen synthase kinase-3 (GSK-3), histone deacetylase (HDAC), brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP) immunohistochemical assays. KET (5 and 10 mg/kg) presented rapid and long-lasting antidepressant-like effects. As expected, the immunoreactivities for brain GSK-3 and HDAC decreased compared to control groups in all areas (striatum, DG, CA1, CA3, and mainly pre-frontal cortex, PFC) after KET injection. Increases in BDNF immunostaining were demonstrated in the PFC, DG, CA1, and CA3 areas at D1 and D30 time-points. GFAP immunoreactivity was also increased in the PFC and striatum at both time-points. In conclusion, KET changed brain BDNF and GFAP expressions 30 days after a single administration. Although neuroplasticity could be involved in the observed effects of KET, more studies are needed to explain the mechanisms for the drug's sustained antidepressant-like effects.

Transcriptomic Changes of Astrocytes in the Brain of Rats with Subacute METH Exposure / 法医学杂志

OBJECTIVES@#To study the transcriptomic changes of astrocytes in the brain of rats exposed to methamphetamine (METH) and its possible mechanism in neurotoxicity.@*METHODS@#The rats were intraperitoneally injected with METH (15 mg/kg) every 12 h for 8 times in total to establish the subacute rat model of METH. After the model was successfully established, the striatum was extracted, and astrocytes were separated by the magnetic bead method. Transcriptome sequencing was performed on selected astrocytes, and the differentially expressed genes were analyzed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis.@*RESULTS@#A total of 876 differentially expressed genes were obtained by transcriptome sequencing, including 321 up-regulated genes and 555 down-regulated genes. GO analysis revealed that differentially expressed genes were mainly concentrated in cell structure, biological process regulation, extracellular matrix and organelle functions. KEGG pathway enrichment analysis showed that steroids biosynthesis, fatty acid biosynthesis, peroxisome proliferators-activated receptor (PPAR), adenosine 5'-monophosphate-activated protein kinase (AMPK) and other signaling pathways were significantly changed.@*CONCLUSIONS@#METH can cause structural changes of astrocytes through multiple targets, among which cellular structure, steroids biosynthesis and fatty acid biosynthesis may play an important role in nerve injury, providing a new idea for forensic identification of METH related death.

Nuclear Factor-κB Signaling Mediates Antimony-induced Astrocyte Activation / 生物医学与环境科学（英文）

Objective@#Antimony (Sb) has recently been identified as a novel nerve poison, although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear. This study aimed to assess the effects of the nuclear factor kappa B (NF-κB) signaling pathway on antimony-induced astrocyte activation.@*Methods@#Protein expression levels were detected by Western blotting. Immunofluorescence, cytoplasmic and nuclear fractions separation were used to assess the distribution of p65. The expression of protein in brain tissue sections was detected by immunohistochemistry. The levels of mRNAs were detected by Quantitative real-time polymerase chain reaction (qRT-PCR) and reverse transcription-polymerase chain reaction (RT-PCR).@*Results@#Antimony exposure triggered astrocyte proliferation and increased the expression of two critical protein markers of reactive astrogliosis, inducible nitric oxide synthase (iNOS) and glial fibrillary acidic protein (GFAP), indicating that antimony induced astrocyte activation @*Conclusion@#Antimony activated astrocytes by activating the NF-κB signaling pathway.

Absence of BAX differentially affects astrocyte density in the mouse cortex and hippocampus / 生理学报

Astrocytes are a heterogenous group of macroglia present in all regions of the brain and play critical roles in many aspects of brain development, function and disease. Previous studies suggest that the B-cell lymphoma-2 associated X protein (BAX)-dependent apoptosis plays essential roles in regulating neuronal number and achieving optimal excitation/inhibition ratio. The aim of the present paper was to study whether BAX regulates astrocyte distribution in a region-specific manner. Immunofluorescence staining of SOX9 was used to analyze and compare astrocyte density in primary somatosensory cortex, motor cortex, retrosplenial cortex and hippocampus in heterozygous and homozygous BAX knockout mice at age of six weeks when cortical development has finished and glia development has reached a relatively steady state. The results showed that astrocyte density varied significantly among different cortical subdivisions and between cortex and hippocampus. In contrast to the significant increase in GABAergic interneurons, the overall and region-specific astrocyte density remained unchanged in the cortex when BAX was absent. Interestingly, a significant reduction of astrocyte density was observed in the hippocampus of BAX knockout mice. These data suggest that BAX differentially regulates neurons and astrocytes in cortex as well as astrocytes in different brain regions during development. This study provided important information about the regional heterogeneity of astrocyte distribution and the potential contribution of BAX gene during development.

Complement C3 Aggravates Post-epileptic Neuronal Injury Via Activation of TRPV1 / 神经科学通报·英文版

Epilepsy is a brain condition characterized by the recurrence of unprovoked seizures. Recent studies have shown that complement component 3 (C3) aggravate the neuronal injury in epilepsy. And our previous studies revealed that TRPV1 (transient receptor potential vanilloid type 1) is involved in epilepsy. Whether complement C3 regulation of neuronal injury is related to the activation of TRPV1 during epilepsy is not fully understood. We found that in a mouse model of status epilepticus (SE), complement C3 derived from astrocytes was increased and aggravated neuronal injury, and that TRPV1-knockout rescued neurons from the injury induced by complement C3. Circular RNAs are abundant in the brain, and the reduction of circRad52 caused by complement C3 promoted the expression of TRPV1 and exacerbated neuronal injury. Mechanistically, disorders of neuron-glia interaction mediated by the C3-TRPV1 signaling pathway may be important for the induction of neuronal injury. This study provides support for the hypothesis that the C3-TRPV1 pathway is involved in the prevention and treatment of neuronal injury and cognitive disorders.