Previous studies on the prenatal organophosphate ester(OPE)exposure's effect on children's neurodevelopment have yielded inconsistent results.In this study,we employed a longitudinal approach,capitalizing on m...Previous studies on the prenatal organophosphate ester(OPE)exposure's effect on children's neurodevelopment have yielded inconsistent results.In this study,we employed a longitudinal approach,capitalizing on multitime-point evaluations of exposure to OPEs and two-stage assessments of children's brain development.The study included 508 mother-child pairs.We measured seven OPEs in maternal serum throughout pregnancy and assessed children's mental health and developmental mile-stones at the age of 2 and 5.The group-based trajectory model identified pregnancy exposure trajectories.Generalized estimated equations and quantile-based g-computation were employed to evaluate the effects of OPEs on children's brain development.Four OPEs,including 2-ethylhexyl diphenyl phosphate(EHDPP),were detected in over 50%of the maternal samples.Each ln-unit increment of EHDPP was associated with an increased peer problem scores(IRR:1.104,95%CI:1.038-1.174)in mental health.Regarding development milestones,EHDPP was related to lower scores in communication,gross motor,personal-social,and total score of the ages and stages questionnaires(ASQ)(IRR:0.963-0.976).Trajectory analysis confirmed these associations.Notably,boys were more affected in terms of mental health,while girls were more vulnerable in terms of developmental milestones.Prenatal exposure to OPEs,particularly EHDPP,is associated with adverse brain development in early childhood with notable sex-specific differences in vulnerability.展开更多
Glial cells are crucial for maintaining central nervous system(CNS)homeostasis.They actively participate in immune responses,as well as form functional barriers,such as blood-brain barrier(BBB),which restrict the entr...Glial cells are crucial for maintaining central nervous system(CNS)homeostasis.They actively participate in immune responses,as well as form functional barriers,such as blood-brain barrier(BBB),which restrict the entry of pathogens and inflammatory mediators into the CNS.In general,viral infections during the gestational period can alter the embryonic and fetal environment,and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life,as highlighted by our group for Zika virus infection.Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)induces a cytokine storm and,during pregnancy,may be related to a more severe form of the coronavirus disease-19(COVID-19)and also to higher preterm birth rates.SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells,which can compromise neuronal plasticity and synaptic function.However,the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS,including brain development during childhood and adulthood,remains undetermined.Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders,which are strongly related to the inflammatory response.Thus,based on these relationships,we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life,focusing on the potential role of glial cells.Thus,it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.展开更多
With the advent of modern techniques, drugs, and monitoring, general anesthesia has come to be considered an unlikely cause of harm, particularly for healthy patients. While this is largely true, newly emerging clinic...With the advent of modern techniques, drugs, and monitoring, general anesthesia has come to be considered an unlikely cause of harm, particularly for healthy patients. While this is largely true, newly emerging clinical and laboratory studies have sug- gested that exposure to anesthetic agents during early childhood may have long-lasting adverse effects on cognitive function. This concern has been the focus of intense study in the field of anesthesia research. A recent high-profile review by Rappaport et al. （2015） concluded that while many questions remain un- answered, there is strong evidence from laboratory studies that commonly used anesthetics interfere with brain development and that clinical studies suggest a correlation between early childhood exposure to these agents and subsequent effects on learning and cognition. The issue is of sufficient public health importance that a public-private partnership known as Smar- Tots （Strategies for Mitigating Anesthesia-Related Neurotoxicity in Tots） was developed by the FDA to study pediatric anesthetic neurotoxicity. The mechanism of injury underlying this phe- nomenon has yet to be fully elucidated, and there is evidence to suggest that anesthetics may have direct cytotoxic effects on neurons leading to cell death or suppressed neurogenesis （Strat- mann et al., 2010） and that they may interfere with key pro- cesses in neuronal growth and development that underlie brain circuit development （Wagner et al., 2014）.展开更多
Tetrabromobisphenol A(TBBPA)is a widely used brominated flame retardant.There is evidence showing that TBBPA can exert thyroid disrupting effects in mammals,but different results were also reported,along with inconsis...Tetrabromobisphenol A(TBBPA)is a widely used brominated flame retardant.There is evidence showing that TBBPA can exert thyroid disrupting effects in mammals,but different results were also reported,along with inconsistent reports regarding its neurotoxicity.Here,we investigated thyroid disrupting effects and neurotoxicity of TBBPA(5,50,500μg/(kg·day))to male mice following maternal and direct exposure through drinking water,with the antithyroid drug propylthiouracil(PTU)as the positive control.On postnatal day(PND)15,we expectedly observed severe thyroid compensatory hyperplasia and cerebellar developmental retardation in PTU-treated pups.The highest dose of TBBPA also caused thyroid histological alteration but had no effects on cerebellar development in terms of Purkinje cell morphology and the thickness of the internal granular layer and the molecular layer of the cerebellum.During puberty and adulthood,the thyroid morphological alterations became more pronounced in the TBBPA-treated animals,accompanied by decreased serum thyroid hormone levels.Furthermore,the 50 and 500μg/(kg·day)TBBPA groups showed a significant decrease in the serum level of serotonin,a neurotransmitter associated with anxiety behaviors.Correspondingly,the highest dose group displayed anxiety-like behaviors in the elevated plus-maze test on PND 35,but this neurobehavioral alteration disappeared on PND 56.Moreover,no changes in neurobehavioral parameters tested were found in TBBPAtreated animals at puberty and adulthood.Altogether,all observations show that TBBPA can exert thyroid disrupting effects but has little overt impact on brain development and neurobehaviors in mice,suggesting that thyroid disruption does not necessarily cause overtly adverse neurodevelopmental outcomes.展开更多
Microglia are the resident immune cells of the central nervous system （CNS）, In the normal state, microglia have a ramified shape and con- tinuously survey the conditions of the brain.
A major basic research projectin the field of neurosciencewas launched on November26 last year at the Shanghai-basedInstitute of Neuroscience of the Chi-nese Academy of Sciences(CAS).
Brain organoids are artificial neural tissues derived in vitro,containing a variety of cell types,as well as structural and/or functional brain regions.They can partially mimic brain physiological activities and disea...Brain organoids are artificial neural tissues derived in vitro,containing a variety of cell types,as well as structural and/or functional brain regions.They can partially mimic brain physiological activities and diseased processes.Owing to their operability and sample accessibility,brain organoids serve as a bridge between in vitro monolayer cell culture models and in vivo animal models.An increasing number of induction protocols for brain organoids have been developed over the preceding decade.A key future research direction will focus on ensuring the complexity and quality of brain organoids.The integration of powerful technologies,such as the CRISP R/Cas9 genome editing and lineage tra cing systems,shall precipitate practical and broad applications of brain organoids.In this review,we discuss the generation and application of brain organoids,as well as their integration with genome editing technologies,in the study of neural development,disease modeling,and mechanistic investigations.The innovative combination of these two technologies may offer a fresh perspective for exploring the fundamental aspects of the human nervous system and related diseases.展开更多
Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine （BrdU） was injected into the brains ...Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine （BrdU） was injected into the brains in different development periods once a day for 7 d. The brains were retrieved 4 weeks after the last BrdU injection. Immunohistochemical and immunofluorescent studies were carried out for detecting cell proliferation （BrdU） and cell differentiation （NeuN, APC, lbal, and S 100β）, respectively. Results The number of BrdU labeled cells decreased significantly with the development of the brain. Cell proliferation was prominent in the cortex and striatum. A small portion of BrdU and NeuN double labeled cells could be detected in the cortex at the early stage of development, and in the striatum and CA of the hippocampus in all groups. The majority of BrdU labeled cells were neuroglia, and the number of neuroglia cells decreased dramatically with brain maturation. Neurogenesis is the major cytogenesis in the dentate gyrus. Conclusion These results demonstrated that cell proliferation, differentiation and survival were age and brain region related.展开更多
Neurodevelopmental processes represent a finely tuned interplay between genetic and environmental factors,shaping the dynamic landscape of the developing brain.A major component of the developing brain that enables th...Neurodevelopmental processes represent a finely tuned interplay between genetic and environmental factors,shaping the dynamic landscape of the developing brain.A major component of the developing brain that enables this dynamic is the white matter(WM),known to be affected in neurodevelopmental disorders(NDDs)(Rokach et al.,2024).WM formation is mediated by myelination,a multifactorial process driven by neuro-glia interactions dependent on proper neuronal functionality(Simons and Trajkovic,2006).Another key aspect of neurodevelopmental abnormalities involves neuronal dynamics and function,with recent advances significantly enhancing our understanding of both neuronal and glial mitochondrial function(Devine and Kittler,2018;Rojas-Charry et al.,2021).Energy homeostasis in neurons,attributed largely to mitochondrial function,is critical for proper functionality and interactions with oligodendrocytes(OLs),the cells forming myelin in the brain’s WM.We herein discuss the interplay between these processes and speculate on potential dysfunction in NDDs.展开更多
Brain development and aging are associated with alterations in multiple epigenetic systems, including DNA methylation and demethylation patterns. Here, we observed that the levels of the 5- hydroxymethylcytosine （5hm...Brain development and aging are associated with alterations in multiple epigenetic systems, including DNA methylation and demethylation patterns. Here, we observed that the levels of the 5- hydroxymethylcytosine （5hmC） ten-eleven transtocation （TET） enzyme-mediated active DNA demethylation products were dynamically changed and involved in postnatal brain development and aging in tree shrews （Tupaia belangeri chinensis）. The levels of 5hmC in multiple anatomic structures showed a gradual increase throughout postnatal development, whereas a significant decrease in 5hmC was found in several brain regions in aged tree shrews, including in the prefrontal cortex and hippocampus, but not the cerebellum. Active changes in Tet mRNA levels indicated that TET2 and TET3 predominantly contributed to the changes in 5hmC levels. Our findings provide new insight into the dynamic changes in 5hmC levels in tree shrew brains during postnatal development and aging processes.展开更多
Objective To study the developmental changes of glutamic acid decarboxylase-67 （ GAD-67, a GABA synthetic enzyme） in normal and hypoxic ischemic （HI） brain. Methods C57/BL6 mice on postnatal day （P） 5, 9, 21 and...Objective To study the developmental changes of glutamic acid decarboxylase-67 （ GAD-67, a GABA synthetic enzyme） in normal and hypoxic ischemic （HI） brain. Methods C57/BL6 mice on postnatal day （P） 5, 9, 21 and 60, corresponding developmentally to premature, term, juvenile and adult human brain were investigated by using both Western blot and immunohistochemistry methods either in normal condition or after hypoxic ischemic insult. Results The immunoreactivity of GAD67 was up regulated with brain development and significant difference was seen between mature （P21, P60） and immature （P5, P9） brain. GAD67 immunoreactivity decreased in the ipsilateral hemisphere in all the ages after hypoxia ischemia （HI） insult, but, significant decrease was only seen in the immature brain. Double labeling of GAD67 and cell death marker, TUNEL, in the cortex at 8h post-HI in the P9 mice showed that （15.6±7.0）% TUNEL positive cells were GAD67 positive which was higher than that of P60 mice. Conclusion These data suggest that GABAergic neurons in immature brain were more vulnerable to HI insult than that of mature brain.展开更多
Neurogenesis is the process in which neurons are generated from neural stem/progenitor cells(NSCs/NPCs).It involves the proliferation and neuronal fate specification/differentiation of NSCs,as well as migration,maturat...Neurogenesis is the process in which neurons are generated from neural stem/progenitor cells(NSCs/NPCs).It involves the proliferation and neuronal fate specification/differentiation of NSCs,as well as migration,maturation and functional integration of the neuronal progeny into neuronal network.NSCs exhibit the two essential properties of stem cells:self-renewal and multi-potency.Contrary to previous dogma that neurogenesis happens only during development,it is generally accepted now that neurogenesis can take place throughout life in mammalian brains.This raises a new therapeutic potential of applying stem cell therapy for stroke,neurodegenerative diseases and other diseases.However,the maintenance and differentiation of NSCs/NPCs are tightly controlled by the extremely intricate molecular networks.Uncovering the underlying mechanisms that drive the differentiation,migration and maturation of specific neuronal lineages for use in regenerative medicine is,therefore,crucial for the application of stem cell for clinical therapy as well as for providing insight into the mechanisms of human neurogenesis.Here,we focus on the role of bone morphogenetic protein(BMP)signaling in NSCs during mammalian brain development.展开更多
Maternal health during pregnancy has a direct impact on the risk and severity of neurodevelopmental disorders(NDDs)in the offspring,especially in the case of drug exposure.However,little progress has been made to asse...Maternal health during pregnancy has a direct impact on the risk and severity of neurodevelopmental disorders(NDDs)in the offspring,especially in the case of drug exposure.However,little progress has been made to assess the risk of drug exposure during pregnancy due to ethical constraints and drug use factors.We collected and manually curated sub-pathways and pathways(sub-/pathways)and drug information to propose an analytical framework for predicting drug candidates.This framework linked sub-/pathway activity and drug response scores derived from gene transcription data and was applied to human fetal brain development and six NDDs.Further,specific and pleiotropic sub-/pathways/drugs were identified using entropy,and sex bias was analyzed in conjunction with logistic regression and random forest models.We identified 19 disorder-associated and 256 regionally pleiotropic and specific candidate drugs that targeted risk sub-/pathways in NDDs,showing temporal or spatial changes across fetal development.Moreover,5443 differential drug-sub-/pathways exhibited sex-biased differences after filling in the gender labels.A user-friendly NDDP visualization website(https://ndd-lab.shinyapps.io/NDDP)was developed to allow researchers and clinicians to access and retrieve data easily.Our framework overcame data gaps and identified numerous pleiotropic and specific candidates across six disorders and fetal developmental trajectories.This could significantly contribute to drug discovery during pregnancy and can be applied to a wide range of traits.展开更多
BACKGROUND： Studies have explored changes in neonatal rat glucocorticoid receptor （GR） expression changes following mature brain injury. OBJECTIVE： To investigate the temporal and special changes of GR during brai...BACKGROUND： Studies have explored changes in neonatal rat glucocorticoid receptor （GR） expression changes following mature brain injury. OBJECTIVE： To investigate the temporal and special changes of GR during brain development in rats with recurrent seizures. DESIGN, TIME AND SE＇n＇ING： A randomized, controlled animal experiment was performed at the Department of Pediatrics, Second Xiangya Hospital of Central South University, from February 2008 to March 2009. MATERIALS： Rabbit anti-rat GR monoclonal antibody was purchased from Santa Cruz Biotechnology, USA; goat anti-rabbit IgG was purchased from Zhongshan Goldenbridge Biotechnology, China. METHODS： A total of 48 Sprague-Dawley rats, 7 days old, were randomly assigned to control and seizure groups, with 24 animals in each group. Seizures were induced by inhalant flurothyl. MAIN OUTCOME MEASURES： Changes in GR protein expression in the rat cerebral cortex were detected by Western blotting analysis and immunohistochemistry. RESULTS： GR expression in the cerebral cortex of control rats significantly increased with aging （P 〈 0.05）, and varied in the frontal lobe, temporal lobe, and parietal lobe. GR was predominantly expressed in the cytoplasm early and rapidly increased in the nuclei. GR protein expression in the cerebral cortex after seizure was lower in the cytoplasm at 15 days and in nuclear protein at 19 days. CONCLUSION： GR expression displayed temporal and spatial changes in brain development. Recurrent seizures in neonatal rats cause abnormal GR expression and might play an important role in developing brain injury.展开更多
Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the...Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep cond让ions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory” of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circu让 and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, no des and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB- 131115-H0075 on November 15, 2013.展开更多
Tree shrews（also named banxrings）,the small mammals native to Southeast Asia,are featured by moderate size,easy breeding,high reproductivity and close genetic background to primates（Xu et al.,2012;Xiao et al.,2017...Tree shrews（also named banxrings）,the small mammals native to Southeast Asia,are featured by moderate size,easy breeding,high reproductivity and close genetic background to primates（Xu et al.,2012;Xiao et al.,2017）.Tiee shrews possess both conserved and unique features compared to primates,and thus will become a suitable animal model with modest cost-effciency（Yao,2017）.展开更多
Target of research in subarachnoid hemorrhage（SAH）：The outcome of aneurysmal SAH remains poor despite advances in the diagnosis and treatment.Although many factors related to patients,aneurysms,and institutions,as ...Target of research in subarachnoid hemorrhage（SAH）：The outcome of aneurysmal SAH remains poor despite advances in the diagnosis and treatment.Although many factors related to patients,aneurysms,and institutions,as well as physiological parameters and medical complications were reported as prognostic factors,展开更多
In the present study, 7 day postnatal C57/BL6 wild-type mice （hyperoxia group） and 7 day postnatal N-methyI-D-aspartate receptor subtype 3A knockout mice （NR3A KO group） were exposed to 75% oxygen and 15% nitrogen...In the present study, 7 day postnatal C57/BL6 wild-type mice （hyperoxia group） and 7 day postnatal N-methyI-D-aspartate receptor subtype 3A knockout mice （NR3A KO group） were exposed to 75% oxygen and 15% nitrogen in a closed container for 5 days. Wild-type mice raised in normoxia served as controls. TdT-mediated dUTP nick end labeling （TUNEL）/neuron-specific nuclear protein （NeuN） and 5-bromo-2＇-deoxyuridine （BrdU）/NeuN immunofluorescence staining showed that the number of apoptotic cells and the number of proliferative cells in the dentate subgranular zone significantly increased in the hyperoxia group compared with the control group. However, in the same hyperoxia environment, the number of apoptotic cells and the number of proliferative cells significantly decreased in the NR3A KO group compared with hyperoxia group. TUNEL＋/NeuN＋ and BrdU＋/NeuN~ cells were observed in the NR3A KO and the hyperoxia groups. These results demonstrated that the NR3A gene can promote cell apoptosis and mediate the potential damage in the developing brain induced by exposure to non-physiologically high concentrations of oxygen.展开更多
BACKGROUND： Cell culture in vitro trials have demonstrated that neurotrophin-3 （NT-3） can enhance the survival of sensory neurons and sympathetic neurons, and can also support embryo-derived motor neurons. This eff...BACKGROUND： Cell culture in vitro trials have demonstrated that neurotrophin-3 （NT-3） can enhance the survival of sensory neurons and sympathetic neurons, and can also support embryo-derived motor neurons. This effect is dependent on nerve growth factor on the surface of cells. Understanding the role of NT-3 and its receptor in the early development of human embryonic brains will help to investigate the correlation between early survival of nerve cells and the microenvironment of neural regeneration. OBJECTIVE： To observe the proliferation of cerebral neurons in the development of human embryonic brain, and to investigate the location, expression and distribution of NT-3 and its receptor TrkC during human brain development. DESIGN, TIME AND SETTING： An observation study on cells was performed in the Department of ttuman Anatomy, Histology and Embryology, Chengdu Medical College in September 2007. MATERIALS： Fifteen specimens of flesh human embryo, aged 6 weeks, were used in this study. METHODS： The proliferation of cerebral neurons was detected using proliferating cell nuclear antigen, and the immunocytochemistry ABC technique was applied to observe the location, expression and distribution of NT-3 and its receptor TrkC in the brain of the human embryo. MAIN OUTCOME MEASURES： Location, expression and distribution of NT-3 and its receptor in the brain of the human embryo. RESULTS： In the early period （aged 6 weeks） of human embryonic development, proliferating cell nuclear antigen-positive reactive substances were mainly observed in the nucleus of the forebrain ventricular zone and subventricular zone, and the intensity was stronger in the subventricular zone than the forebrain ventricle. NT-3 positive reactive substance was mainly distributed in the cytoblastema of the forebrain neuroepithelial layer and nerve cell process, while TrkC was mainly distributed in the cell membrane of the forebrain ventricular zone and subventricular zone. During embryonic development, NT-3 and TrkC showed a positive immune reaction to a greater or lesser extent in ependymal epithelium. CONCLUSION： During early human embryonic development, cerebral nerve cells proliferate in the ventricular zone and subventricular zone, and NT-3 is expressed in the neural axon. The results show that the highly expressed NT-3 could promote the proliferation of neural axons and maintain the neuron body＇s survival.展开更多
基金supported by the National Natural Science Foundation of China[Grant numbers:82273585,81872581]the Shanghai 3-year Public Health Action Plan(Grant number:GWVI-11.1-39).
文摘Previous studies on the prenatal organophosphate ester(OPE)exposure's effect on children's neurodevelopment have yielded inconsistent results.In this study,we employed a longitudinal approach,capitalizing on multitime-point evaluations of exposure to OPEs and two-stage assessments of children's brain development.The study included 508 mother-child pairs.We measured seven OPEs in maternal serum throughout pregnancy and assessed children's mental health and developmental mile-stones at the age of 2 and 5.The group-based trajectory model identified pregnancy exposure trajectories.Generalized estimated equations and quantile-based g-computation were employed to evaluate the effects of OPEs on children's brain development.Four OPEs,including 2-ethylhexyl diphenyl phosphate(EHDPP),were detected in over 50%of the maternal samples.Each ln-unit increment of EHDPP was associated with an increased peer problem scores(IRR:1.104,95%CI:1.038-1.174)in mental health.Regarding development milestones,EHDPP was related to lower scores in communication,gross motor,personal-social,and total score of the ages and stages questionnaires(ASQ)(IRR:0.963-0.976).Trajectory analysis confirmed these associations.Notably,boys were more affected in terms of mental health,while girls were more vulnerable in terms of developmental milestones.Prenatal exposure to OPEs,particularly EHDPP,is associated with adverse brain development in early childhood with notable sex-specific differences in vulnerability.
基金The authors are supported by Universidade Federal do Rio Grande do Sul(UFRGS),Conselho Nacional de Desenvolvimento Científico e Tecnológico(CNPq),Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES),Fundação de AmparoàPesquisa do Estado do Rio Grande do Sul(FAPERGS),and Instituto Nacional de Ciência e Tecnologia para Excitotoxicidade e Neuroproteção(INCTEN/CNPq).
文摘Glial cells are crucial for maintaining central nervous system(CNS)homeostasis.They actively participate in immune responses,as well as form functional barriers,such as blood-brain barrier(BBB),which restrict the entry of pathogens and inflammatory mediators into the CNS.In general,viral infections during the gestational period can alter the embryonic and fetal environment,and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life,as highlighted by our group for Zika virus infection.Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)induces a cytokine storm and,during pregnancy,may be related to a more severe form of the coronavirus disease-19(COVID-19)and also to higher preterm birth rates.SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells,which can compromise neuronal plasticity and synaptic function.However,the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS,including brain development during childhood and adulthood,remains undetermined.Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders,which are strongly related to the inflammatory response.Thus,based on these relationships,we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life,focusing on the potential role of glial cells.Thus,it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.
文摘With the advent of modern techniques, drugs, and monitoring, general anesthesia has come to be considered an unlikely cause of harm, particularly for healthy patients. While this is largely true, newly emerging clinical and laboratory studies have sug- gested that exposure to anesthetic agents during early childhood may have long-lasting adverse effects on cognitive function. This concern has been the focus of intense study in the field of anesthesia research. A recent high-profile review by Rappaport et al. （2015） concluded that while many questions remain un- answered, there is strong evidence from laboratory studies that commonly used anesthetics interfere with brain development and that clinical studies suggest a correlation between early childhood exposure to these agents and subsequent effects on learning and cognition. The issue is of sufficient public health importance that a public-private partnership known as Smar- Tots （Strategies for Mitigating Anesthesia-Related Neurotoxicity in Tots） was developed by the FDA to study pediatric anesthetic neurotoxicity. The mechanism of injury underlying this phe- nomenon has yet to be fully elucidated, and there is evidence to suggest that anesthetics may have direct cytotoxic effects on neurons leading to cell death or suppressed neurogenesis （Strat- mann et al., 2010） and that they may interfere with key pro- cesses in neuronal growth and development that underlie brain circuit development （Wagner et al., 2014）.
基金supported by the National Key Research and Development Program of China(No.2018YFA0901103)the National Natural Science Foundation of China(No.21876196)。
文摘Tetrabromobisphenol A(TBBPA)is a widely used brominated flame retardant.There is evidence showing that TBBPA can exert thyroid disrupting effects in mammals,but different results were also reported,along with inconsistent reports regarding its neurotoxicity.Here,we investigated thyroid disrupting effects and neurotoxicity of TBBPA(5,50,500μg/(kg·day))to male mice following maternal and direct exposure through drinking water,with the antithyroid drug propylthiouracil(PTU)as the positive control.On postnatal day(PND)15,we expectedly observed severe thyroid compensatory hyperplasia and cerebellar developmental retardation in PTU-treated pups.The highest dose of TBBPA also caused thyroid histological alteration but had no effects on cerebellar development in terms of Purkinje cell morphology and the thickness of the internal granular layer and the molecular layer of the cerebellum.During puberty and adulthood,the thyroid morphological alterations became more pronounced in the TBBPA-treated animals,accompanied by decreased serum thyroid hormone levels.Furthermore,the 50 and 500μg/(kg·day)TBBPA groups showed a significant decrease in the serum level of serotonin,a neurotransmitter associated with anxiety behaviors.Correspondingly,the highest dose group displayed anxiety-like behaviors in the elevated plus-maze test on PND 35,but this neurobehavioral alteration disappeared on PND 56.Moreover,no changes in neurobehavioral parameters tested were found in TBBPAtreated animals at puberty and adulthood.Altogether,all observations show that TBBPA can exert thyroid disrupting effects but has little overt impact on brain development and neurobehaviors in mice,suggesting that thyroid disruption does not necessarily cause overtly adverse neurodevelopmental outcomes.
文摘Microglia are the resident immune cells of the central nervous system （CNS）, In the normal state, microglia have a ramified shape and con- tinuously survey the conditions of the brain.
文摘A major basic research projectin the field of neurosciencewas launched on November26 last year at the Shanghai-basedInstitute of Neuroscience of the Chi-nese Academy of Sciences(CAS).
基金Special Projectfor Clinical Research of Shanghai Municipal Health Commission,No.202140403Key Disciplines Group Construction Project of Pudong Health Bureau of Shanghai,No.PWZxq2022-05+2 种基金Natural Science Foundation of Ningxia Hui Autonomous Region,No.2024AAC05084Ningxia Hui Autonomous Region Key Research and Development Program,No.2021BEG03084National Natural Science Foundation of China,Nos.32370895,32070862。
文摘Brain organoids are artificial neural tissues derived in vitro,containing a variety of cell types,as well as structural and/or functional brain regions.They can partially mimic brain physiological activities and diseased processes.Owing to their operability and sample accessibility,brain organoids serve as a bridge between in vitro monolayer cell culture models and in vivo animal models.An increasing number of induction protocols for brain organoids have been developed over the preceding decade.A key future research direction will focus on ensuring the complexity and quality of brain organoids.The integration of powerful technologies,such as the CRISP R/Cas9 genome editing and lineage tra cing systems,shall precipitate practical and broad applications of brain organoids.In this review,we discuss the generation and application of brain organoids,as well as their integration with genome editing technologies,in the study of neural development,disease modeling,and mechanistic investigations.The innovative combination of these two technologies may offer a fresh perspective for exploring the fundamental aspects of the human nervous system and related diseases.
基金This work was supported by the grant of National Natural Science Foundation of China （No. 30470598）.
文摘Objective To investigate the cell proliferation and differentiation in the developing brain of mouse. Methods C57/BL6 mice were divided into 3 groups at random. Bromodeoxyuridine （BrdU） was injected into the brains in different development periods once a day for 7 d. The brains were retrieved 4 weeks after the last BrdU injection. Immunohistochemical and immunofluorescent studies were carried out for detecting cell proliferation （BrdU） and cell differentiation （NeuN, APC, lbal, and S 100β）, respectively. Results The number of BrdU labeled cells decreased significantly with the development of the brain. Cell proliferation was prominent in the cortex and striatum. A small portion of BrdU and NeuN double labeled cells could be detected in the cortex at the early stage of development, and in the striatum and CA of the hippocampus in all groups. The majority of BrdU labeled cells were neuroglia, and the number of neuroglia cells decreased dramatically with brain maturation. Neurogenesis is the major cytogenesis in the dentate gyrus. Conclusion These results demonstrated that cell proliferation, differentiation and survival were age and brain region related.
文摘Neurodevelopmental processes represent a finely tuned interplay between genetic and environmental factors,shaping the dynamic landscape of the developing brain.A major component of the developing brain that enables this dynamic is the white matter(WM),known to be affected in neurodevelopmental disorders(NDDs)(Rokach et al.,2024).WM formation is mediated by myelination,a multifactorial process driven by neuro-glia interactions dependent on proper neuronal functionality(Simons and Trajkovic,2006).Another key aspect of neurodevelopmental abnormalities involves neuronal dynamics and function,with recent advances significantly enhancing our understanding of both neuronal and glial mitochondrial function(Devine and Kittler,2018;Rojas-Charry et al.,2021).Energy homeostasis in neurons,attributed largely to mitochondrial function,is critical for proper functionality and interactions with oligodendrocytes(OLs),the cells forming myelin in the brain’s WM.We herein discuss the interplay between these processes and speculate on potential dysfunction in NDDs.
基金supported by the Hundred-Talent Program of Chinese Academy of Sciences(Y4065411411100050210)to J.L.+3 种基金the National Natural Science Foundation of China(8147131391649119)to J.L.the National Natural Science Foundation of China(31260242 to)F.Lthe National Science and Technology Infrastructure Program(2014BAI01B01-04)to S.L.
文摘Brain development and aging are associated with alterations in multiple epigenetic systems, including DNA methylation and demethylation patterns. Here, we observed that the levels of the 5- hydroxymethylcytosine （5hmC） ten-eleven transtocation （TET） enzyme-mediated active DNA demethylation products were dynamically changed and involved in postnatal brain development and aging in tree shrews （Tupaia belangeri chinensis）. The levels of 5hmC in multiple anatomic structures showed a gradual increase throughout postnatal development, whereas a significant decrease in 5hmC was found in several brain regions in aged tree shrews, including in the prefrontal cortex and hippocampus, but not the cerebellum. Active changes in Tet mRNA levels indicated that TET2 and TET3 predominantly contributed to the changes in 5hmC levels. Our findings provide new insight into the dynamic changes in 5hmC levels in tree shrew brains during postnatal development and aging processes.
基金This work was supported by the Natural Science Foundation of China （30470598）.
文摘Objective To study the developmental changes of glutamic acid decarboxylase-67 （ GAD-67, a GABA synthetic enzyme） in normal and hypoxic ischemic （HI） brain. Methods C57/BL6 mice on postnatal day （P） 5, 9, 21 and 60, corresponding developmentally to premature, term, juvenile and adult human brain were investigated by using both Western blot and immunohistochemistry methods either in normal condition or after hypoxic ischemic insult. Results The immunoreactivity of GAD67 was up regulated with brain development and significant difference was seen between mature （P21, P60） and immature （P5, P9） brain. GAD67 immunoreactivity decreased in the ipsilateral hemisphere in all the ages after hypoxia ischemia （HI） insult, but, significant decrease was only seen in the immature brain. Double labeling of GAD67 and cell death marker, TUNEL, in the cortex at 8h post-HI in the P9 mice showed that （15.6±7.0）% TUNEL positive cells were GAD67 positive which was higher than that of P60 mice. Conclusion These data suggest that GABAergic neurons in immature brain were more vulnerable to HI insult than that of mature brain.
文摘Neurogenesis is the process in which neurons are generated from neural stem/progenitor cells(NSCs/NPCs).It involves the proliferation and neuronal fate specification/differentiation of NSCs,as well as migration,maturation and functional integration of the neuronal progeny into neuronal network.NSCs exhibit the two essential properties of stem cells:self-renewal and multi-potency.Contrary to previous dogma that neurogenesis happens only during development,it is generally accepted now that neurogenesis can take place throughout life in mammalian brains.This raises a new therapeutic potential of applying stem cell therapy for stroke,neurodegenerative diseases and other diseases.However,the maintenance and differentiation of NSCs/NPCs are tightly controlled by the extremely intricate molecular networks.Uncovering the underlying mechanisms that drive the differentiation,migration and maturation of specific neuronal lineages for use in regenerative medicine is,therefore,crucial for the application of stem cell for clinical therapy as well as for providing insight into the mechanisms of human neurogenesis.Here,we focus on the role of bone morphogenetic protein(BMP)signaling in NSCs during mammalian brain development.
基金supported by the National Natural Science Foundation of China[81701350 and 31671252]the Health Technology Plan of Zhejiang Province[2023RC205].
文摘Maternal health during pregnancy has a direct impact on the risk and severity of neurodevelopmental disorders(NDDs)in the offspring,especially in the case of drug exposure.However,little progress has been made to assess the risk of drug exposure during pregnancy due to ethical constraints and drug use factors.We collected and manually curated sub-pathways and pathways(sub-/pathways)and drug information to propose an analytical framework for predicting drug candidates.This framework linked sub-/pathway activity and drug response scores derived from gene transcription data and was applied to human fetal brain development and six NDDs.Further,specific and pleiotropic sub-/pathways/drugs were identified using entropy,and sex bias was analyzed in conjunction with logistic regression and random forest models.We identified 19 disorder-associated and 256 regionally pleiotropic and specific candidate drugs that targeted risk sub-/pathways in NDDs,showing temporal or spatial changes across fetal development.Moreover,5443 differential drug-sub-/pathways exhibited sex-biased differences after filling in the gender labels.A user-friendly NDDP visualization website(https://ndd-lab.shinyapps.io/NDDP)was developed to allow researchers and clinicians to access and retrieve data easily.Our framework overcame data gaps and identified numerous pleiotropic and specific candidates across six disorders and fetal developmental trajectories.This could significantly contribute to drug discovery during pregnancy and can be applied to a wide range of traits.
基金the National Natural Science Foundation of China,No.30400483the Natural Science Foundation of Hunan Province,No.07JJ5020
文摘BACKGROUND： Studies have explored changes in neonatal rat glucocorticoid receptor （GR） expression changes following mature brain injury. OBJECTIVE： To investigate the temporal and special changes of GR during brain development in rats with recurrent seizures. DESIGN, TIME AND SE＇n＇ING： A randomized, controlled animal experiment was performed at the Department of Pediatrics, Second Xiangya Hospital of Central South University, from February 2008 to March 2009. MATERIALS： Rabbit anti-rat GR monoclonal antibody was purchased from Santa Cruz Biotechnology, USA; goat anti-rabbit IgG was purchased from Zhongshan Goldenbridge Biotechnology, China. METHODS： A total of 48 Sprague-Dawley rats, 7 days old, were randomly assigned to control and seizure groups, with 24 animals in each group. Seizures were induced by inhalant flurothyl. MAIN OUTCOME MEASURES： Changes in GR protein expression in the rat cerebral cortex were detected by Western blotting analysis and immunohistochemistry. RESULTS： GR expression in the cerebral cortex of control rats significantly increased with aging （P 〈 0.05）, and varied in the frontal lobe, temporal lobe, and parietal lobe. GR was predominantly expressed in the cytoplasm early and rapidly increased in the nuclei. GR protein expression in the cerebral cortex after seizure was lower in the cytoplasm at 15 days and in nuclear protein at 19 days. CONCLUSION： GR expression displayed temporal and spatial changes in brain development. Recurrent seizures in neonatal rats cause abnormal GR expression and might play an important role in developing brain injury.
基金supported by the Natural Science Foundation of Guangdong Province,No.2016A030313180(to FCJ)
文摘Previous studies on brain functional connectivity networks in children have mainly focused on changes in function in specific brain regions, as opposed to whole brain connectivity in healthy children. By analyzing the independent components of activation and network connectivity between brain regions, we examined brain activity status and development trends in children aged 3 and 5 years. These data could provide a reference for brain function rehabilitation in children with illness or abnormal function. We acquired functional magnetic resonance images from 15 3-year-old children and 15 5-year-old children under natural sleep cond让ions. The participants were recruited from five kindergartens in the Nanshan District of Shenzhen City, China. The parents of the participants signed an informed consent form with the premise that they had been fully informed regarding the experimental protocol. We used masked independent component analysis and BrainNet Viewer software to explore the independent components of the brain and correlation connections between brain regions. We identified seven independent components in the two groups of children, including the executive control network, the dorsal attention network, the default mode network, the left frontoparietal network, the right frontoparietal network, the salience network, and the motor network. In the default mode network, the posterior cingulate cortex, medial frontal gyrus, and inferior parietal lobule were activated in both 3- and 5-year-old children, supporting the "three-brain region theory” of the default mode network. In the frontoparietal network, the frontal and parietal gyri were activated in the two groups of children, and functional connectivity was strengthened in 5-year-olds compared with 3-year-olds, although the nodes and network connections were not yet mature. The high-correlation network connections in the default mode networks and dorsal attention networks had been significantly strengthened in 5-year-olds vs. 3-year-olds. Further, the salience network in the 3-year-old children included an activated insula/inferior frontal gyrus-anterior cingulate cortex network circu让 and an activated thalamus-parahippocampal-posterior cingulate cortex-subcortical regions network circuit. By the age of 5 years, no des and high-correlation network connections (edges) were reduced in the salience network. Overall, activation of the dorsal attention network, default mode network, left frontoparietal network, and right frontoparietal network increased (the volume of activation increased, the signals strengthened, and the high-correlation connections increased and strengthened) in 5-year-olds compared with 3-year-olds, but activation in some brain nodes weakened or disappeared in the salience network, and the network connections (edges) were reduced. Between the ages of 3 and 5 years, we observed a tendency for function in some brain regions to be strengthened and for the generalization of activation to be reduced, indicating that specialization begins to develop at this time. The study protocol was approved by the local ethics committee of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences in China with approval No. SIAT-IRB- 131115-H0075 on November 15, 2013.
基金supported by the National Natural Science Foundation of China(No.31600841)the Shanghai brain-intelligence project from STCSM(16JC1420500)the Beijing brain project (Z161100002616004)
文摘Tree shrews（also named banxrings）,the small mammals native to Southeast Asia,are featured by moderate size,easy breeding,high reproductivity and close genetic background to primates（Xu et al.,2012;Xiao et al.,2017）.Tiee shrews possess both conserved and unique features compared to primates,and thus will become a suitable animal model with modest cost-effciency（Yao,2017）.
基金supported by a Grant-in-Aid for Scientific Research from Mie Medical Research Foundation to HS
文摘Target of research in subarachnoid hemorrhage（SAH）：The outcome of aneurysmal SAH remains poor despite advances in the diagnosis and treatment.Although many factors related to patients,aneurysms,and institutions,as well as physiological parameters and medical complications were reported as prognostic factors,
基金supported by the National Institutes of Health, USA, No. NS 045810, NS 057255the BasicClinical Scientific Research Foundation Program of the Capital Medical University, China, No. 2006JL19
文摘In the present study, 7 day postnatal C57/BL6 wild-type mice （hyperoxia group） and 7 day postnatal N-methyI-D-aspartate receptor subtype 3A knockout mice （NR3A KO group） were exposed to 75% oxygen and 15% nitrogen in a closed container for 5 days. Wild-type mice raised in normoxia served as controls. TdT-mediated dUTP nick end labeling （TUNEL）/neuron-specific nuclear protein （NeuN） and 5-bromo-2＇-deoxyuridine （BrdU）/NeuN immunofluorescence staining showed that the number of apoptotic cells and the number of proliferative cells in the dentate subgranular zone significantly increased in the hyperoxia group compared with the control group. However, in the same hyperoxia environment, the number of apoptotic cells and the number of proliferative cells significantly decreased in the NR3A KO group compared with hyperoxia group. TUNEL＋/NeuN＋ and BrdU＋/NeuN~ cells were observed in the NR3A KO and the hyperoxia groups. These results demonstrated that the NR3A gene can promote cell apoptosis and mediate the potential damage in the developing brain induced by exposure to non-physiologically high concentrations of oxygen.
文摘BACKGROUND： Cell culture in vitro trials have demonstrated that neurotrophin-3 （NT-3） can enhance the survival of sensory neurons and sympathetic neurons, and can also support embryo-derived motor neurons. This effect is dependent on nerve growth factor on the surface of cells. Understanding the role of NT-3 and its receptor in the early development of human embryonic brains will help to investigate the correlation between early survival of nerve cells and the microenvironment of neural regeneration. OBJECTIVE： To observe the proliferation of cerebral neurons in the development of human embryonic brain, and to investigate the location, expression and distribution of NT-3 and its receptor TrkC during human brain development. DESIGN, TIME AND SETTING： An observation study on cells was performed in the Department of ttuman Anatomy, Histology and Embryology, Chengdu Medical College in September 2007. MATERIALS： Fifteen specimens of flesh human embryo, aged 6 weeks, were used in this study. METHODS： The proliferation of cerebral neurons was detected using proliferating cell nuclear antigen, and the immunocytochemistry ABC technique was applied to observe the location, expression and distribution of NT-3 and its receptor TrkC in the brain of the human embryo. MAIN OUTCOME MEASURES： Location, expression and distribution of NT-3 and its receptor in the brain of the human embryo. RESULTS： In the early period （aged 6 weeks） of human embryonic development, proliferating cell nuclear antigen-positive reactive substances were mainly observed in the nucleus of the forebrain ventricular zone and subventricular zone, and the intensity was stronger in the subventricular zone than the forebrain ventricle. NT-3 positive reactive substance was mainly distributed in the cytoblastema of the forebrain neuroepithelial layer and nerve cell process, while TrkC was mainly distributed in the cell membrane of the forebrain ventricular zone and subventricular zone. During embryonic development, NT-3 and TrkC showed a positive immune reaction to a greater or lesser extent in ependymal epithelium. CONCLUSION： During early human embryonic development, cerebral nerve cells proliferate in the ventricular zone and subventricular zone, and NT-3 is expressed in the neural axon. The results show that the highly expressed NT-3 could promote the proliferation of neural axons and maintain the neuron body＇s survival.
