Adult hippocampal neurogenesis is linked to memory formation in the adult brain,with new neurons in the hippocampus exhibiting greater plasticity during their immature stages compared to mature neurons.Abnormal adult ...Adult hippocampal neurogenesis is linked to memory formation in the adult brain,with new neurons in the hippocampus exhibiting greater plasticity during their immature stages compared to mature neurons.Abnormal adult hippocampal neurogenesis is closely associated with cognitive impairment in central nervous system diseases.Targeting and regulating adult hippocampal neurogenesis have been shown to improve cognitive deficits.This review aims to expand the current understanding and prospects of targeting neurogenesis in the treatment of cognitive impairment.Recent research indicates the presence of abnormalities in AHN in several diseases associated with cognitive impairment,including cerebrovascular diseases,Alzheimer's disease,aging-related conditions,and issues related to anesthesia and surgery.The role of these abnormalities in the cognitive deficits caused by these diseases has been widely recognized,and targeting AHN is considered a promising approach for treating cognitive impairment.However,the underlying mechanisms of this role are not yet fully understood,and the effectiveness of targeting abnormal adult hippocampal neurogenesis for treatment remains limited,with a need for further development of treatment methods and detection techniques.By reviewing recent studies,we classify the potential mechanisms of adult hippocampal neurogenesis abnormalities into four categories:immunity,energy metabolism,aging,and pathological states.In immunity-related mechanisms,abnormalities in meningeal,brain,and peripheral immunity can disrupt normal adult hippocampal neurogenesis.Lipid metabolism and mitochondrial function disorders are significant energy metabolism factors that lead to abnormal adult hippocampal neurogenesis.During aging,the inflammatory state of the neurogenic niche and the expression of aging-related microRNAs contribute to reduced adult hippocampal neurogenesis and cognitive impairment in older adult patients.Pathological states of the body and emotional disorders may also result in abnormal adult hippocampal neurogenesis.Among the current strategies used to enhance this form of neurogenesis,physical therapies such as exercise,transcutaneous electrical nerve stimulation,and enriched environments have proven effective.Dietary interventions,including energy intake restriction and nutrient optimization,have shown efficacy in both basic research and clinical trials.However,drug treatments,such as antidepressants and stem cell therapy,are primarily reported in basic research,with limited clinical application.The relationship between abnormal adult hippocampal neurogenesis and cognitive impairment has garnered widespread attention,and targeting the former may be an important strategy for treating the latter.However,the mechanisms underlying abnormal adult hippocampal neurogenesis remain unclear,and treatments are lacking.This highlights the need for greater focus on translating research findings into clinical practice.展开更多
Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within t...Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within the ischemic brain,these mechanisms are often insufficient to restore neuronal functionality.This has led to intensive investigation into the use of exogenous stem cells as a potential therapeutic option.This comprehensive review outlines the ontogeny and mechanisms of activation of endogenous neural stem cells within the adult brain following ischemic events,with focus on the impact of stem cell-based therapies on neural stem cells.Exogenous stem cells have been shown to enhance the proliferation of endogenous neural stem cells via direct cell-tocell contact and through the secretion of growth factors and exosomes.Additionally,implanted stem cells may recruit host stem cells from their niches to the infarct area by establishing so-called“biobridges.”Furthermore,xenogeneic and allogeneic stem cells can modify the microenvironment of the infarcted brain tissue through immunomodulatory and angiogenic effects,thereby supporting endogenous neuroregeneration.Given the convergence of regulatory pathways between exogenous and endogenous stem cells and the necessity for a supportive microenvironment,we discuss three strategies to simultaneously enhance the therapeutic efficacy of both cell types.These approaches include:(1)co-administration of various growth factors and pharmacological agents alongside stem cell transplantation to reduce stem cell apoptosis;(2)synergistic administration of stem cells and their exosomes to amplify paracrine effects;and(3)integration of stem cells within hydrogels,which provide a protective scaffold for the implanted cells while facilitating the regeneration of neural tissue and the reconstitution of neural circuits.This comprehensive review highlights the interactions and shared regulatory mechanisms between endogenous neural stem cells and exogenously implanted stem cells and may offer new insights for improving the efficacy of stem cell-based therapies in the treatment of ischemic stroke.展开更多
Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive impairment.However,the mechanism underlying this neurogenesis impairment remains unknown.In ...Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive impairment.However,the mechanism underlying this neurogenesis impairment remains unknown.In this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain injury.Our results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and spines.Mice with repetitive traumatic brain injuryalso showed deficits in spatial memory retrieval.Moreover,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was downregulated.An inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological function.These findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.展开更多
Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rode...Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rodents and improves memory and slows cognitive decline in patients with Alzheimer’s disease.However,the molecular pathways for exercise-induced adult hippocampal neurogenesis and improved cognition in Alzheimer’s disease are poorly understood.Recently,regulator of G protein signaling 6(RGS6)was identified as the mediator of voluntary running-induced adult hippocampal neurogenesis in mice.Here,we generated novel RGS6fl/fl;APP_(SWE) mice and used retroviral approaches to examine the impact of RGS6 deletion from dentate gyrus neuronal progenitor cells on voluntary running-induced adult hippocampal neurogenesis and cognition in an amyloid-based Alzheimer’s disease mouse model.We found that voluntary running in APP_(SWE) mice restored their hippocampal cognitive impairments to that of control mice.This cognitive rescue was abolished by RGS6 deletion in dentate gyrus neuronal progenitor cells,which also abolished running-mediated increases in adult hippocampal neurogenesis.Adult hippocampal neurogenesis was reduced in sedentary APP_(SWE) mice versus control mice,with basal adult hippocampal neurogenesis reduced by RGS6 deletion in dentate gyrus neural precursor cells.RGS6 was expressed in neurons within the dentate gyrus of patients with Alzheimer’s disease with significant loss of these RGS6-expressing neurons.Thus,RGS6 mediated voluntary running-induced rescue of impaired cognition and adult hippocampal neurogenesis in APP_(SWE) mice,identifying RGS6 in dentate gyrus neural precursor cells as a possible therapeutic target in Alzheimer’s disease.展开更多
After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact...After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact are not well understood.In this work,we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury.To this end,we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms.First,using the Tg(fli1:EGFP×mpeg1.1:mCherry)zebrafish line,which enables visualization of blood vessels and microglia respectively,we analyzed regenerative angiogenesis from 1 to 21 days post-lesion.In parallel,we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry.We found that after brain damage,the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor(vegfaa and vegfbb)were increased.At the same time,neural stem cell proliferation was also increased,peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis,along with the recruitment of microglia.Then,through pharmacological manipulation by injecting an anti-angiogenic drug(Tivozanib)or Vegf at the lesion site,we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes,as well as microglial recruitment.Finally,we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis,as previously described,as well as injury-induced angiogenesis.In conclusion,we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process.In addition,we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes.This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury.展开更多
Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. T...Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier function.However, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could provide valuable insights into potential therapeutic strategies for Alzheimer's disease and related conditions.展开更多
Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inh...Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior.展开更多
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne...The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.展开更多
Loss-of-function variants in CSDE1 have been strongly linked to neuropsychiatric disorders,yet the precise role of CSDE1 in neurogenesis remains elusive.In this study,we demonstrate that knockout of Csde1 during corti...Loss-of-function variants in CSDE1 have been strongly linked to neuropsychiatric disorders,yet the precise role of CSDE1 in neurogenesis remains elusive.In this study,we demonstrate that knockout of Csde1 during cortical development in mice results in impaired neural progenitor proliferation,leading to abnormal cortical lamination and embryonic lethality.Transcriptomic analysis revealed that Csde1 upregulates the transcription of genes involved in the cell cycle network.Applying a dual thymidine-labelling approach,we further revealed prolonged cell cycle durations of neuronal progenitors in Csde1-knockout mice,with a notable extension of the G1 phase.Intersection with CLIP-seq data demonstrated that Csde1 binds to the 3′untranslated region(UTR)of mRNA transcripts encoding cell cycle genes.Particularly,we uncovered that Csde1 directly binds to the 3′UTR of mRNA transcripts encoding Cdk6,a pivotal gene in regulating the transition from the G1 to S phases of the cell cycle,thereby maintaining its stability.Collectively,this study elucidates Csde1 as a novel regulator of Cdk6,sheds new light on its critical roles in orchestrating brain development,and underscores how mutations in Csde1 may contribute to the pathogenesis of neuropsychiatric disorders.展开更多
Current scientific endeavours in the field of geroscience have begun to reveal how factors such as exercise could modulate the brain aging process.In this review,we ask how exercise could potentially modulate aging,an...Current scientific endeavours in the field of geroscience have begun to reveal how factors such as exercise could modulate the brain aging process.In this review,we ask how exercise could potentially modulate aging,and by extension,the development of Alzheimer’s Disease(AD).Furthermore,we discuss how exercise could mitigate the cascade of debilitating manifestations in AD.Mechanistically,we discuss how biomolecules such as brain-derived neurotrophic factor(BDNF)and its cognate receptor,tropomyosin receptor kinase B(TrkB)could change during the life course and how its signalling pathways could be altered with exercise(acute sessions or chronic training).Tackling these questions could help the scientific and medical community mitigate age-related decline in terms of neurological functions.展开更多
This article focused on the recent contribution by Jiang et al,who demonstrated that voluntary exercise can significantly potentiate the effects of induced pluripotent stem cell transplantation in a Parkinson’s disea...This article focused on the recent contribution by Jiang et al,who demonstrated that voluntary exercise can significantly potentiate the effects of induced pluripotent stem cell transplantation in a Parkinson’s disease(PD)model through activation of the Wnt1-Lmx1a signaling cascade.Jiang et al’s findings highlight the role of exercise as a molecular modulator of neurogenesis and support the development of integrated strategies combining physical activity,stem cell transplantation,and biomaterials to improve outcomes in PD.We highlight exercise as a molecular modulator that fosters a neurogenic milieu,recommend examining additional developmental signals(sonic hedgehog,fibroblast growth factor 8,bone morphogenetic protein),and suggest biomaterial-based strategies to support graft survival and integration.We also stress the need to optimize exercise regimens in relation to transplantation,framing these insights within a translational strategy for advancing regenerative therapies in PD.展开更多
Background:Chronic Gulf War Illness(GWI)is characterized by cognitive and mood impairments,as well as persistent neuroinflammation and oxidative stress.This study aimed to investigate the efficacy of Epidiolex®,a...Background:Chronic Gulf War Illness(GWI)is characterized by cognitive and mood impairments,as well as persistent neuroinflammation and oxidative stress.This study aimed to investigate the efficacy of Epidiolex®,a Food and Drug Administration(FDA)-approved cannabidiol(CBD),in improving brain function in a rat model of chronic GWI.Methods:Six months after exposure to low doses of GWI-related chemicals[pyridostigmine bromide,N,N-diethyl-meta-toluamide(DEET),and permethrin(PER)]along with moderate stress,rats with chronic GWI were administered either vehicle(VEH)or CBD(20 mg/kg,oral)for 16 weeks.Neurobehavioral tests were conducted on 11 weeks after treatment initiation to evaluate the performance of rats in tasks related to associative recognition memory,object location memory,pattern separation,and sucrose preference.The effect of CBD on hyperalgesia was also examined.The brain tissues were processed for immunohistochemical and molecular studies following behavioral tests.Results:GWI rats treated with VEH exhibited impairments in all cognitive tasks and anhedonia,whereas CBD-treated GWI rats showed improvements in all cognitive tasks and no anhedonia.Additionally,CBD treatment alleviated hyperalgesia in GWI rats.Analysis of hippocampal tissues from VEH-treated rats revealed astrocyte hypertrophy and increased percentages of activated microglia presenting NOD-,LRR-and pyrin domain-containing protein 3(NLRP3)complexes as well as elevated levels of proteins involved in NLRP3 inflammasome activation and Janus kinase/signal transducers and activators of the transcription(JAK/STAT)signaling.Furthermore,there were increased concentrations of proinflammatory and oxidative stress markers along with decreased neurogenesis.In contrast,the hippocampus from CBD-treated GWI rats displayed reduced levels of proteins mediating the activation of NLRP3 inflammasomes and JAK/STAT signaling,normalized concentrations of proinflammatory cytokines and oxidative stress markers,and improved neurogenesis.Notably,CBD treatment did not alter the concentration of endogenous cannabinoid anandamide in the hippocampus.Conclusions:The use of an FDA-approved CBD(Epidiolex®)has been shown to effectively alleviate cognitive and mood impairments as well as hyperalgesia associated with chronic GWI.Importantly,the improvements observed in rats with chronic GWI in this study were attributed to the ability of CBD to significantly suppress signaling pathways that perpetuate chronic neuroinflammation.展开更多
The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DNA synthesis.Since the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immuno...The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DNA synthesis.Since the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating DNA.BrdU labeling is widely used for identifying neuron precursors and following their fate during the embryonic,perinatal,and adult neurogenesis in a variety of vertebrate species including birds,reptiles,and mammals.Due to BrdU toxicity,its incorporation into replicating DNA presents adverse consequences on the generation,survival,and settled patterns of cells.This may lead to false results and misinterpretation in the identification of proliferative neuroblasts.In this review,I will indicate the detrimental effects of this nucleoside during the development of the central nervous system,as well as the reliability of BrdU labeling to detect proliferating neuroblasts.Moreover,it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal,perinatal,and adult neurogenesis.Human adult neurogenesis will also be discussed.It is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.展开更多
To study the effects of oestrogcn on ischemia-induced neurogenesis in the hippocampal dentate gyms, thirty-two adult male rats were randomly divided into four groups: the control surgery group with eestrogen administ...To study the effects of oestrogcn on ischemia-induced neurogenesis in the hippocampal dentate gyms, thirty-two adult male rats were randomly divided into four groups: the control surgery group with eestrogen administration (SE), the control surgery group with normal saline administration (SN), the middle cerebral artery occlusion (MCAO) group with oestrogen administration (ME) and the MCAO group with normal saline administration (MN). The MCAO rats were occluded for 90 rain by an intraluminal filament and then recirculated. After 1, 3, 12, 24 and 28 h of MCAO, the rats of the four groups were killed to investigate the infarct volume, apoptosis and neurogenesis. The cerebral infarct volume in the ME group was significantly smaller than that of the MN group (P 〈 0.05). No significant cell loss was seen in the dentate gyms. Cerebral ischemia led to increased neurogenosis, which is independent of cell death in the ipsilateral dentate gyrus(P 〈 0.05). BrdU-pesitive cells in the ipsilateral dentate gyms of the ME group were significantly increased when compared with those of the MN group(P 〈 0.05). In the SE group, BrdU-positive cells in both the ipsilateral and contralateral dentate gyms, were increased when compared with those of the SN group ( P 〈 0.05 ). We concluded that ocstregen plays an important role in neurogenesis, which is independent of ischemia-induced by MCAO in the hippocampal dentate gyms of rats.展开更多
Neural stem cells give rise to neurons through the process of neurogenesis, which includes neural stem cell proliferation, fate deter- mination of new neurons, as well as the new neuron's migration, maturation and in...Neural stem cells give rise to neurons through the process of neurogenesis, which includes neural stem cell proliferation, fate deter- mination of new neurons, as well as the new neuron's migration, maturation and integration. Currently, neurogenesis is divided into two phases: embryonic and adult phases. Embryonic neurogenesis occurs at high levels to form the central nervous system. Adult neurogenesis has been consistently identified only in restricted regions and occurs at low levels. As the basic process for embryonic neurodevelopment and adult brain maintenance, neurogenesis is tightly regulated by many factors and pathways. MicroRNA, short non-coding RNA that regulates gene expression at the post-transcriptional level, appears to be involved in multiple steps of neurogenesis. This review summarizes the emerging role of microRNAs in regulating embryonic and adult neurogenesis, with a particular emphasis on the proliferation and differentiation of neural stem cells.展开更多
Embryonic neurogenesis is the process of generating neurons,the functional units of the brain.Because of its sensitivity to adverse intrauterine environment such as infection,dysregulation of this process has emerged ...Embryonic neurogenesis is the process of generating neurons,the functional units of the brain.Because of its sensitivity to adverse intrauterine environment such as infection,dysregulation of this process has emerged as a key mechanism underlying many neurodevelopmental disorders such as autism spectrum disorders(ASD).Adult neurogenesis,although is restricted to a few neurogenic niches,plays pivotal roles in brain plasticity and repair.Increasing evidence suggests that impairments in adult neurogenesis are involved in major neurodegenerative disorders such as Alzheimer's disease.A hallmark feature of these brain disorders is neuroinflammation,which can either promote or inhibit neurogenesis depending upon the context of brain microenvironment.In this review paper,we present evidence from both experimental and human studies to show a complex picture of relationship between these two events,and discussed potential factors contributing to different or even opposing actions of neuroinflammation on neurogenesis in neurodevelopmental and neurological disorders.展开更多
Mechanisms regulating neurogenesis involve broad and complex processes that represent intriguing therapeutic targets in the field of regenerative medicine.One influential factor guiding neural stem cell proliferation ...Mechanisms regulating neurogenesis involve broad and complex processes that represent intriguing therapeutic targets in the field of regenerative medicine.One influential factor guiding neural stem cell proliferation and cellular differentiation during neurogenesis are epigenetic mechanisms.We present an overview of epigenetic mechanisms including chromatin structure and histone modifications;and discuss novel roles of two histone modifiers,Ezh2 and Suv4-20h1/Suv4-20h2(collectively referred to as Suv4-20h),in neurodevelopment and neurogenesis.This review will focus on broadly reviewing epigenetic regulatory components,the roles of epigenetic components during neurogenesis,and potential applications in regenerative medicine.展开更多
We investigated the distribution of gamma aminobutyric acid, tyrosine hydroxylase and nitric oxide-producing elements in a cherry salmon Oncorhynchus masou brain at various stages of postnatal ontogenesis by immunohis...We investigated the distribution of gamma aminobutyric acid, tyrosine hydroxylase and nitric oxide-producing elements in a cherry salmon Oncorhynchus masou brain at various stages of postnatal ontogenesis by immunohistochemical staining and histochemical staining. The periventricular region cells exhibited the morphology of neurons and glia including radial glia-like cells and contained several neurochemical substances. Heterogeneous populations of tyrosine hydroxylase-, gamma aminobutyric acid-immunoreactive, as well as nicotinamide adenine dinucleotide phosphate diaphorase-positive cells were observed in proliferating cell nuclear antigen-immunoreactive proliferative zones in periventricular area of diencephalon, central grey layer of dorsomedial tegmentum, medulla and spinal cord. Immunolocalization of Pax6 in the cherry salmon brain revealed a neuromeric construction of the brain at various stages of postnatal ontogenesis, and this was confirmed by tyrosine hydroxylase and gamma aminobutyric acid labeling.展开更多
Objective Statins inhibit hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase activity and lower total serum cholesterol levels. We investigated the effects of Pravastatin on neuroprotection and neurogenesis in the...Objective Statins inhibit hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase activity and lower total serum cholesterol levels. We investigated the effects of Pravastatin on neuroprotection and neurogenesis in the dentate gyrus (DG), subventricular zone (SVZ) and striatum after cerebral ischemia in rats. Methods The filament method was used for temporary middle cerebral artery occlusion (tMCAO). Pravastatin or saline post-ischemically were administered at subsequent time points: 6 h after tMCAO, and then on every subsequent day up to day 14 after tMCAO. Neurological outcome was investigated by using a neuroscore, the beam balance test and the rotarod test. Cholesterol and triglycerides levels were determined by blood sample analysis prior to sacrifice. Infarct area was calculated by microtubule-associated protein 2 (MAP2) staining. Neurogenesis was evaluated by triple staining with bromodeoxyuridine (BrdU), doublecortin (DCX), and neuronal nuclei (NeuN). Results Compared with the control groups, Pravastatin treated animals were significantly improved in neurological outcome in rotarod test, with smaller infarct size. Pravastatin increased BrdU- positive cells number in the DG (P = 0.0029) and the SVZ (P = 0.0280) but not in the striatum (P = 0.3929). Furthermore, Pravastatin increased BrdU-labeled DCX positive cells number in the DG (P = 0.0031), SVZ (P = 0.0316) and striatum (P = 0.0073). We also observed a DCX-positive cells stream from the SVZ to the striatum, suggesting a migration route of those immature neurons. No significant differences of total serum cholesterol and triglycerides were observed between groups. Conclusion The Pravastatin administration strategy is safe and could promote neurological recovery in ischemic stroke. Pravastatin induces neurogenesis in the DG and SVZ, and increases the number of migration cells in the striatum. These effects are independent of the cholesterol-lowering property of Pravastatin.展开更多
Studies have shown that mesenchymal stem cell-derived exosomes can enhance neural plasticity and improve cognitive impairment.The purpose of this study was to investigate the effects of mesenchymal stem cell-derived e...Studies have shown that mesenchymal stem cell-derived exosomes can enhance neural plasticity and improve cognitive impairment.The purpose of this study was to investigate the effects of mesenchymal stem cell-derived exosomes on neurogenesis and cognitive capacity in a mouse model of Alzheimer’s disease.Alzheimer’s disease mouse models were established by injection of beta amyloid 1?42 aggregates into dentate gyrus bilaterally.Morris water maze and novel object recognition tests were performed to evaluate mouse cognitive deficits at 14 and 28 days after administration.Afterwards,neurogenesis in the subventricular zone was determined by immunofluorescence using doublecortin and PSA-NCAM antibodies.Results showed that mesenchymal stem cells-derived exosomes stimulated neurogenesis in the subventricular zone and alleviated beta amyloid 1?42-induced cognitive impairment,and these effects are similar to those shown in the mesenchymal stem cells.These findings provide evidence to validate the possibility of developing cell-free therapeutic strategies for Alzheimer’s disease.All procedures and experiments were approved by Institutional Animal Care and Use Committee(CICUAL)(approval No.CICUAL 2016-011)on April 25,2016.展开更多
基金supported by Technological Innovation 2030-Major Projects of“Brain Science and Brain-like Research,”No.2022ZD0206200(to XG)the National Natural Science Foundation of China,No.82371245(to SJ),82102246(to XD),81701092(to XG)+2 种基金the Natural Science Foundation of Shandong Province,No.ZR2020MH129(to SJ)Shanghai Municipal Key Clinical Specialty,No.shslczdzk03601Shanghai Engineering Research Center of Peri-operative Organ Support and Function Preservation,No.20DZ2254200。
文摘Adult hippocampal neurogenesis is linked to memory formation in the adult brain,with new neurons in the hippocampus exhibiting greater plasticity during their immature stages compared to mature neurons.Abnormal adult hippocampal neurogenesis is closely associated with cognitive impairment in central nervous system diseases.Targeting and regulating adult hippocampal neurogenesis have been shown to improve cognitive deficits.This review aims to expand the current understanding and prospects of targeting neurogenesis in the treatment of cognitive impairment.Recent research indicates the presence of abnormalities in AHN in several diseases associated with cognitive impairment,including cerebrovascular diseases,Alzheimer's disease,aging-related conditions,and issues related to anesthesia and surgery.The role of these abnormalities in the cognitive deficits caused by these diseases has been widely recognized,and targeting AHN is considered a promising approach for treating cognitive impairment.However,the underlying mechanisms of this role are not yet fully understood,and the effectiveness of targeting abnormal adult hippocampal neurogenesis for treatment remains limited,with a need for further development of treatment methods and detection techniques.By reviewing recent studies,we classify the potential mechanisms of adult hippocampal neurogenesis abnormalities into four categories:immunity,energy metabolism,aging,and pathological states.In immunity-related mechanisms,abnormalities in meningeal,brain,and peripheral immunity can disrupt normal adult hippocampal neurogenesis.Lipid metabolism and mitochondrial function disorders are significant energy metabolism factors that lead to abnormal adult hippocampal neurogenesis.During aging,the inflammatory state of the neurogenic niche and the expression of aging-related microRNAs contribute to reduced adult hippocampal neurogenesis and cognitive impairment in older adult patients.Pathological states of the body and emotional disorders may also result in abnormal adult hippocampal neurogenesis.Among the current strategies used to enhance this form of neurogenesis,physical therapies such as exercise,transcutaneous electrical nerve stimulation,and enriched environments have proven effective.Dietary interventions,including energy intake restriction and nutrient optimization,have shown efficacy in both basic research and clinical trials.However,drug treatments,such as antidepressants and stem cell therapy,are primarily reported in basic research,with limited clinical application.The relationship between abnormal adult hippocampal neurogenesis and cognitive impairment has garnered widespread attention,and targeting the former may be an important strategy for treating the latter.However,the mechanisms underlying abnormal adult hippocampal neurogenesis remain unclear,and treatments are lacking.This highlights the need for greater focus on translating research findings into clinical practice.
基金supported by the National Key Research and Development Program of China,No.2018YFA0108602the CAMS Initiative for Innovative Medicine,No.2021-1-I2M-019National High-Level Hospital Clinical Research Funding,No.2022-PUMCH-C-042(all to XB)。
文摘Ischemic stroke is a significant global health crisis,frequently resulting in disability or death,with limited therapeutic interventions available.Although various intrinsic reparative processes are initiated within the ischemic brain,these mechanisms are often insufficient to restore neuronal functionality.This has led to intensive investigation into the use of exogenous stem cells as a potential therapeutic option.This comprehensive review outlines the ontogeny and mechanisms of activation of endogenous neural stem cells within the adult brain following ischemic events,with focus on the impact of stem cell-based therapies on neural stem cells.Exogenous stem cells have been shown to enhance the proliferation of endogenous neural stem cells via direct cell-tocell contact and through the secretion of growth factors and exosomes.Additionally,implanted stem cells may recruit host stem cells from their niches to the infarct area by establishing so-called“biobridges.”Furthermore,xenogeneic and allogeneic stem cells can modify the microenvironment of the infarcted brain tissue through immunomodulatory and angiogenic effects,thereby supporting endogenous neuroregeneration.Given the convergence of regulatory pathways between exogenous and endogenous stem cells and the necessity for a supportive microenvironment,we discuss three strategies to simultaneously enhance the therapeutic efficacy of both cell types.These approaches include:(1)co-administration of various growth factors and pharmacological agents alongside stem cell transplantation to reduce stem cell apoptosis;(2)synergistic administration of stem cells and their exosomes to amplify paracrine effects;and(3)integration of stem cells within hydrogels,which provide a protective scaffold for the implanted cells while facilitating the regeneration of neural tissue and the reconstitution of neural circuits.This comprehensive review highlights the interactions and shared regulatory mechanisms between endogenous neural stem cells and exogenously implanted stem cells and may offer new insights for improving the efficacy of stem cell-based therapies in the treatment of ischemic stroke.
基金supported by the Fundamental Research Program of Shanxi Province of China,No.20210302124277the Science Foundation of Shanxi Bethune Hospital,No.2021YJ13(both to JW)。
文摘Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive impairment.However,the mechanism underlying this neurogenesis impairment remains unknown.In this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain injury.Our results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and spines.Mice with repetitive traumatic brain injuryalso showed deficits in spatial memory retrieval.Moreover,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was downregulated.An inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological function.These findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.
基金supported by the National Institutes of Health,Nos.AA025919,AA025919-03S1,and AA025919-05S1(all to RAF).
文摘Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s disease.Adult hippocampal neurogenesis is reduced in patients with Alzheimer’s disease.Exercise stimulates adult hippocampal neurogenesis in rodents and improves memory and slows cognitive decline in patients with Alzheimer’s disease.However,the molecular pathways for exercise-induced adult hippocampal neurogenesis and improved cognition in Alzheimer’s disease are poorly understood.Recently,regulator of G protein signaling 6(RGS6)was identified as the mediator of voluntary running-induced adult hippocampal neurogenesis in mice.Here,we generated novel RGS6fl/fl;APP_(SWE) mice and used retroviral approaches to examine the impact of RGS6 deletion from dentate gyrus neuronal progenitor cells on voluntary running-induced adult hippocampal neurogenesis and cognition in an amyloid-based Alzheimer’s disease mouse model.We found that voluntary running in APP_(SWE) mice restored their hippocampal cognitive impairments to that of control mice.This cognitive rescue was abolished by RGS6 deletion in dentate gyrus neuronal progenitor cells,which also abolished running-mediated increases in adult hippocampal neurogenesis.Adult hippocampal neurogenesis was reduced in sedentary APP_(SWE) mice versus control mice,with basal adult hippocampal neurogenesis reduced by RGS6 deletion in dentate gyrus neural precursor cells.RGS6 was expressed in neurons within the dentate gyrus of patients with Alzheimer’s disease with significant loss of these RGS6-expressing neurons.Thus,RGS6 mediated voluntary running-induced rescue of impaired cognition and adult hippocampal neurogenesis in APP_(SWE) mice,identifying RGS6 in dentate gyrus neural precursor cells as a possible therapeutic target in Alzheimer’s disease.
基金supported by European Regional Development Funds RE0022527 ZEBRATOX(EU-Région Réunion-French State national counterpart,to Nicolas Diotel and Jean-Loup Bascands).
文摘After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact are not well understood.In this work,we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury.To this end,we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms.First,using the Tg(fli1:EGFP×mpeg1.1:mCherry)zebrafish line,which enables visualization of blood vessels and microglia respectively,we analyzed regenerative angiogenesis from 1 to 21 days post-lesion.In parallel,we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry.We found that after brain damage,the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor(vegfaa and vegfbb)were increased.At the same time,neural stem cell proliferation was also increased,peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis,along with the recruitment of microglia.Then,through pharmacological manipulation by injecting an anti-angiogenic drug(Tivozanib)or Vegf at the lesion site,we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes,as well as microglial recruitment.Finally,we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis,as previously described,as well as injury-induced angiogenesis.In conclusion,we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process.In addition,we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes.This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury.
基金supported by the National Natural Science Foundation of China,Nos.31871477,32170971 (both to SQ)the Qing-Feng Scholar Research Foundation of Shanghai Medical College,Fudan University,No.QF2212 (to HT)。
文摘Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier function.However, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could provide valuable insights into potential therapeutic strategies for Alzheimer's disease and related conditions.
文摘Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior.
基金supported by the National Natural Science Foundation of China,Nos.82272171(to ZY),82271403(to XL),81941011(to XL),31971279(to ZY),31730030(to XL)the Natural Science Foundation of Beijing,No.7222004(to HD).
文摘The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.
基金supported by STI 2030-Major Project(2021ZD0201704)the National Natural Science Foundation of China(32271141,82222025,82130043,82330035,82361138573,82160219,and 82401388)+3 种基金Hunan Provincial Grants(2023SK2084,2023RC1020,2023SK2114,2021SK1010,and 2024JJ6545)China Postdoctoral Science Foundation(2023M733969)Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZB20230875)National Key Research and Development Program of China(2021YFA0805200)。
文摘Loss-of-function variants in CSDE1 have been strongly linked to neuropsychiatric disorders,yet the precise role of CSDE1 in neurogenesis remains elusive.In this study,we demonstrate that knockout of Csde1 during cortical development in mice results in impaired neural progenitor proliferation,leading to abnormal cortical lamination and embryonic lethality.Transcriptomic analysis revealed that Csde1 upregulates the transcription of genes involved in the cell cycle network.Applying a dual thymidine-labelling approach,we further revealed prolonged cell cycle durations of neuronal progenitors in Csde1-knockout mice,with a notable extension of the G1 phase.Intersection with CLIP-seq data demonstrated that Csde1 binds to the 3′untranslated region(UTR)of mRNA transcripts encoding cell cycle genes.Particularly,we uncovered that Csde1 directly binds to the 3′UTR of mRNA transcripts encoding Cdk6,a pivotal gene in regulating the transition from the G1 to S phases of the cell cycle,thereby maintaining its stability.Collectively,this study elucidates Csde1 as a novel regulator of Cdk6,sheds new light on its critical roles in orchestrating brain development,and underscores how mutations in Csde1 may contribute to the pathogenesis of neuropsychiatric disorders.
文摘Current scientific endeavours in the field of geroscience have begun to reveal how factors such as exercise could modulate the brain aging process.In this review,we ask how exercise could potentially modulate aging,and by extension,the development of Alzheimer’s Disease(AD).Furthermore,we discuss how exercise could mitigate the cascade of debilitating manifestations in AD.Mechanistically,we discuss how biomolecules such as brain-derived neurotrophic factor(BDNF)and its cognate receptor,tropomyosin receptor kinase B(TrkB)could change during the life course and how its signalling pathways could be altered with exercise(acute sessions or chronic training).Tackling these questions could help the scientific and medical community mitigate age-related decline in terms of neurological functions.
文摘This article focused on the recent contribution by Jiang et al,who demonstrated that voluntary exercise can significantly potentiate the effects of induced pluripotent stem cell transplantation in a Parkinson’s disease(PD)model through activation of the Wnt1-Lmx1a signaling cascade.Jiang et al’s findings highlight the role of exercise as a molecular modulator of neurogenesis and support the development of integrated strategies combining physical activity,stem cell transplantation,and biomaterials to improve outcomes in PD.We highlight exercise as a molecular modulator that fosters a neurogenic milieu,recommend examining additional developmental signals(sonic hedgehog,fibroblast growth factor 8,bone morphogenetic protein),and suggest biomaterial-based strategies to support graft survival and integration.We also stress the need to optimize exercise regimens in relation to transplantation,framing these insights within a translational strategy for advancing regenerative therapies in PD.
基金supported by grants from Jazz Pharmaceuticals Inc.the Texas A&M University of School of Medicine to AKS
文摘Background:Chronic Gulf War Illness(GWI)is characterized by cognitive and mood impairments,as well as persistent neuroinflammation and oxidative stress.This study aimed to investigate the efficacy of Epidiolex®,a Food and Drug Administration(FDA)-approved cannabidiol(CBD),in improving brain function in a rat model of chronic GWI.Methods:Six months after exposure to low doses of GWI-related chemicals[pyridostigmine bromide,N,N-diethyl-meta-toluamide(DEET),and permethrin(PER)]along with moderate stress,rats with chronic GWI were administered either vehicle(VEH)or CBD(20 mg/kg,oral)for 16 weeks.Neurobehavioral tests were conducted on 11 weeks after treatment initiation to evaluate the performance of rats in tasks related to associative recognition memory,object location memory,pattern separation,and sucrose preference.The effect of CBD on hyperalgesia was also examined.The brain tissues were processed for immunohistochemical and molecular studies following behavioral tests.Results:GWI rats treated with VEH exhibited impairments in all cognitive tasks and anhedonia,whereas CBD-treated GWI rats showed improvements in all cognitive tasks and no anhedonia.Additionally,CBD treatment alleviated hyperalgesia in GWI rats.Analysis of hippocampal tissues from VEH-treated rats revealed astrocyte hypertrophy and increased percentages of activated microglia presenting NOD-,LRR-and pyrin domain-containing protein 3(NLRP3)complexes as well as elevated levels of proteins involved in NLRP3 inflammasome activation and Janus kinase/signal transducers and activators of the transcription(JAK/STAT)signaling.Furthermore,there were increased concentrations of proinflammatory and oxidative stress markers along with decreased neurogenesis.In contrast,the hippocampus from CBD-treated GWI rats displayed reduced levels of proteins mediating the activation of NLRP3 inflammasomes and JAK/STAT signaling,normalized concentrations of proinflammatory cytokines and oxidative stress markers,and improved neurogenesis.Notably,CBD treatment did not alter the concentration of endogenous cannabinoid anandamide in the hippocampus.Conclusions:The use of an FDA-approved CBD(Epidiolex®)has been shown to effectively alleviate cognitive and mood impairments as well as hyperalgesia associated with chronic GWI.Importantly,the improvements observed in rats with chronic GWI in this study were attributed to the ability of CBD to significantly suppress signaling pathways that perpetuate chronic neuroinflammation.
文摘The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DNA synthesis.Since the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating DNA.BrdU labeling is widely used for identifying neuron precursors and following their fate during the embryonic,perinatal,and adult neurogenesis in a variety of vertebrate species including birds,reptiles,and mammals.Due to BrdU toxicity,its incorporation into replicating DNA presents adverse consequences on the generation,survival,and settled patterns of cells.This may lead to false results and misinterpretation in the identification of proliferative neuroblasts.In this review,I will indicate the detrimental effects of this nucleoside during the development of the central nervous system,as well as the reliability of BrdU labeling to detect proliferating neuroblasts.Moreover,it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal,perinatal,and adult neurogenesis.Human adult neurogenesis will also be discussed.It is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.
文摘To study the effects of oestrogcn on ischemia-induced neurogenesis in the hippocampal dentate gyms, thirty-two adult male rats were randomly divided into four groups: the control surgery group with eestrogen administration (SE), the control surgery group with normal saline administration (SN), the middle cerebral artery occlusion (MCAO) group with oestrogen administration (ME) and the MCAO group with normal saline administration (MN). The MCAO rats were occluded for 90 rain by an intraluminal filament and then recirculated. After 1, 3, 12, 24 and 28 h of MCAO, the rats of the four groups were killed to investigate the infarct volume, apoptosis and neurogenesis. The cerebral infarct volume in the ME group was significantly smaller than that of the MN group (P 〈 0.05). No significant cell loss was seen in the dentate gyms. Cerebral ischemia led to increased neurogenosis, which is independent of cell death in the ipsilateral dentate gyrus(P 〈 0.05). BrdU-pesitive cells in the ipsilateral dentate gyms of the ME group were significantly increased when compared with those of the MN group(P 〈 0.05). In the SE group, BrdU-positive cells in both the ipsilateral and contralateral dentate gyms, were increased when compared with those of the SN group ( P 〈 0.05 ). We concluded that ocstregen plays an important role in neurogenesis, which is independent of ischemia-induced by MCAO in the hippocampal dentate gyms of rats.
基金supported by the grants from the Chinese Academy of Sciences(No.XDA01020301)the Hundred Talent Program
文摘Neural stem cells give rise to neurons through the process of neurogenesis, which includes neural stem cell proliferation, fate deter- mination of new neurons, as well as the new neuron's migration, maturation and integration. Currently, neurogenesis is divided into two phases: embryonic and adult phases. Embryonic neurogenesis occurs at high levels to form the central nervous system. Adult neurogenesis has been consistently identified only in restricted regions and occurs at low levels. As the basic process for embryonic neurodevelopment and adult brain maintenance, neurogenesis is tightly regulated by many factors and pathways. MicroRNA, short non-coding RNA that regulates gene expression at the post-transcriptional level, appears to be involved in multiple steps of neurogenesis. This review summarizes the emerging role of microRNAs in regulating embryonic and adult neurogenesis, with a particular emphasis on the proliferation and differentiation of neural stem cells.
基金supported by grants from NIH(R01NS080844)(LWF)Michael J.Fox foundation(YP)+1 种基金Intramural Research Support Program(YP)the Department of Pediatrics,University of Mississippi Medical Center
文摘Embryonic neurogenesis is the process of generating neurons,the functional units of the brain.Because of its sensitivity to adverse intrauterine environment such as infection,dysregulation of this process has emerged as a key mechanism underlying many neurodevelopmental disorders such as autism spectrum disorders(ASD).Adult neurogenesis,although is restricted to a few neurogenic niches,plays pivotal roles in brain plasticity and repair.Increasing evidence suggests that impairments in adult neurogenesis are involved in major neurodegenerative disorders such as Alzheimer's disease.A hallmark feature of these brain disorders is neuroinflammation,which can either promote or inhibit neurogenesis depending upon the context of brain microenvironment.In this review paper,we present evidence from both experimental and human studies to show a complex picture of relationship between these two events,and discussed potential factors contributing to different or even opposing actions of neuroinflammation on neurogenesis in neurodevelopmental and neurological disorders.
文摘Mechanisms regulating neurogenesis involve broad and complex processes that represent intriguing therapeutic targets in the field of regenerative medicine.One influential factor guiding neural stem cell proliferation and cellular differentiation during neurogenesis are epigenetic mechanisms.We present an overview of epigenetic mechanisms including chromatin structure and histone modifications;and discuss novel roles of two histone modifiers,Ezh2 and Suv4-20h1/Suv4-20h2(collectively referred to as Suv4-20h),in neurodevelopment and neurogenesis.This review will focus on broadly reviewing epigenetic regulatory components,the roles of epigenetic components during neurogenesis,and potential applications in regenerative medicine.
基金supported by a grant from Far Eastern Branch of Russian Academy of Sciences, No.12-Ⅲ-A-06-095
文摘We investigated the distribution of gamma aminobutyric acid, tyrosine hydroxylase and nitric oxide-producing elements in a cherry salmon Oncorhynchus masou brain at various stages of postnatal ontogenesis by immunohistochemical staining and histochemical staining. The periventricular region cells exhibited the morphology of neurons and glia including radial glia-like cells and contained several neurochemical substances. Heterogeneous populations of tyrosine hydroxylase-, gamma aminobutyric acid-immunoreactive, as well as nicotinamide adenine dinucleotide phosphate diaphorase-positive cells were observed in proliferating cell nuclear antigen-immunoreactive proliferative zones in periventricular area of diencephalon, central grey layer of dorsomedial tegmentum, medulla and spinal cord. Immunolocalization of Pax6 in the cherry salmon brain revealed a neuromeric construction of the brain at various stages of postnatal ontogenesis, and this was confirmed by tyrosine hydroxylase and gamma aminobutyric acid labeling.
文摘Objective Statins inhibit hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase activity and lower total serum cholesterol levels. We investigated the effects of Pravastatin on neuroprotection and neurogenesis in the dentate gyrus (DG), subventricular zone (SVZ) and striatum after cerebral ischemia in rats. Methods The filament method was used for temporary middle cerebral artery occlusion (tMCAO). Pravastatin or saline post-ischemically were administered at subsequent time points: 6 h after tMCAO, and then on every subsequent day up to day 14 after tMCAO. Neurological outcome was investigated by using a neuroscore, the beam balance test and the rotarod test. Cholesterol and triglycerides levels were determined by blood sample analysis prior to sacrifice. Infarct area was calculated by microtubule-associated protein 2 (MAP2) staining. Neurogenesis was evaluated by triple staining with bromodeoxyuridine (BrdU), doublecortin (DCX), and neuronal nuclei (NeuN). Results Compared with the control groups, Pravastatin treated animals were significantly improved in neurological outcome in rotarod test, with smaller infarct size. Pravastatin increased BrdU- positive cells number in the DG (P = 0.0029) and the SVZ (P = 0.0280) but not in the striatum (P = 0.3929). Furthermore, Pravastatin increased BrdU-labeled DCX positive cells number in the DG (P = 0.0031), SVZ (P = 0.0316) and striatum (P = 0.0073). We also observed a DCX-positive cells stream from the SVZ to the striatum, suggesting a migration route of those immature neurons. No significant differences of total serum cholesterol and triglycerides were observed between groups. Conclusion The Pravastatin administration strategy is safe and could promote neurological recovery in ischemic stroke. Pravastatin induces neurogenesis in the DG and SVZ, and increases the number of migration cells in the striatum. These effects are independent of the cholesterol-lowering property of Pravastatin.
基金sponsored by CONACYT scholarship#487713Fondo Mixto de Ciencia y Tecnología del Estado de Jalisco grant JAL-2014-0-250508
文摘Studies have shown that mesenchymal stem cell-derived exosomes can enhance neural plasticity and improve cognitive impairment.The purpose of this study was to investigate the effects of mesenchymal stem cell-derived exosomes on neurogenesis and cognitive capacity in a mouse model of Alzheimer’s disease.Alzheimer’s disease mouse models were established by injection of beta amyloid 1?42 aggregates into dentate gyrus bilaterally.Morris water maze and novel object recognition tests were performed to evaluate mouse cognitive deficits at 14 and 28 days after administration.Afterwards,neurogenesis in the subventricular zone was determined by immunofluorescence using doublecortin and PSA-NCAM antibodies.Results showed that mesenchymal stem cells-derived exosomes stimulated neurogenesis in the subventricular zone and alleviated beta amyloid 1?42-induced cognitive impairment,and these effects are similar to those shown in the mesenchymal stem cells.These findings provide evidence to validate the possibility of developing cell-free therapeutic strategies for Alzheimer’s disease.All procedures and experiments were approved by Institutional Animal Care and Use Committee(CICUAL)(approval No.CICUAL 2016-011)on April 25,2016.