Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience...Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders.展开更多
Microglia are the resident macrophages of the central nervous system.Microglia possess varied morphologies and functions.Under normal physiological conditions,microglia mainly exist in a resting state and constantly m...Microglia are the resident macrophages of the central nervous system.Microglia possess varied morphologies and functions.Under normal physiological conditions,microglia mainly exist in a resting state and constantly monitor their microenvironment and survey neuronal and synaptic activity.Through the C1 q,C3 and CR3"Eat Me"and CD47 and SIRPα"Don't Eat Me"complement pathways,as well as other pathways such as CX3 CR1 signaling,resting microglia regulate synaptic pruning,a process crucial for the promotion of synapse formation and the regulation of neuronal activity and synaptic plasticity.By mediating synaptic pruning,resting microglia play an important role in the regulation of experience-dependent plasticity in the barrel cortex and visual cortex after whisker removal or monocular deprivation,and also in the regulation of learning and memory,including the modulation of memory strength,forgetfulness,and memory quality.As a response to brain injury,infection or neuroinflammation,microglia become activated and increase in number.Activated microglia change to an amoeboid shape,migrate to sites of inflammation and secrete proteins such as cytokines,chemokines and reactive oxygen species.These molecules released by microglia can lead to synaptic plasticity and learning and memory deficits associated with aging,Alzheimer's disease,traumatic brain injury,HIV-associated neurocognitive disorder,and other neurological or mental disorders such as autism,depression and post-traumatic stress disorder.With a focus mainly on recently published literature,here we reviewed the studies investigating the role of resting microglia in synaptic plasticity and learning and memory,as well as how activated microglia modulate disease-related plasticity and learning and memory deficits.By summarizing the function of microglia in these processes,we aim to provide an overview of microglia regulation of synaptic plasticity and learning and memory,and to discuss the possibility of microglia manipulation as a therapeutic to ameliorate cognitive deficits associated with aging,Alzheimer's disease,traumatic brain injury,HIV-associated neurocognitive disorder,and mental disorders.展开更多
Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fig...Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fight or flee is barely known. Here, we review our work on crickets that reveals the roles of biogenic amines, primarily octopamine (the insect analog of noradrenaline) and nitric oxide (NO). Using aminergic drugs, we found that amines are not essential for actually initiating aggres- sion. However, octopamine is necessary for mediating the aggression-promoting effects of poten- tially rewarding experiences including stimulation with a male antenna, physical exertion, winning, and resource possession. Hence, octopamine can be considered as the motivational component of aggression. Imposed handicaps that impede aggressive signaling revealed that the agonistic actions of an opponent perceived during fighting act to reduce aggression, and that crickets make the deci- sion to flee the moment the accumulated sum of such aversive experiences exceeds some critical level. Treatment with nitridergic drugs revealed that the impact of the opponent's aggressive actions is mediated by NO. NO acts to suppress aggression by promoting the tendency to flee and is primarily responsible for the depressed aggressiveness of subordinates after social defeat. Octopamine and dopamine can each restore aggression in subordinates, but only dopamine is necessary for normal recovery. The role of serotonin remains unclear, and is discussed. We conclude that octopamine and NO control the decision to fight or flee by mediating the effects of potentially rewarding and aversive experiences, respectively.展开更多
Critical periods(CPs)are defined as postnatal developmental windows during which brain circuits exhibit heightened sensitivity to altered experiences or sensory inputs,particularly during brain development in humans a...Critical periods(CPs)are defined as postnatal developmental windows during which brain circuits exhibit heightened sensitivity to altered experiences or sensory inputs,particularly during brain development in humans and animals.During the CP,experience-induced refinements of neural connections are crucial for establishing adaptive and mature brain functions,and aberrant CPs are often accompanied by many neurodevelopmental disorders(NDDs),including autism spectrum disorders and schizophrenia.Understanding neural mechanisms underlying the CP regulation is key to delineating the etiology of NDDs caused by abnormal postnatal neurodevelopment.Recent evidence from studies using innovative experimental tools has continuously revisited the inhibition-gating theory of CP to systematically elucidate the differential roles of distinct inhibitory circuits.Here,we provide a comprehensive review of classical experimental findings and emerging inhibitory-circuit regulation mechanisms of the CP,and further discuss how aberrant CP plasticity is associated with NDDs.展开更多
基金supported by the National Natural Science Foundation of China,No.31760290,82160688the Key Development Areas Project of Ganzhou Science and Technology,No.2022B-SF9554(all to XL)。
文摘Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders.
文摘Microglia are the resident macrophages of the central nervous system.Microglia possess varied morphologies and functions.Under normal physiological conditions,microglia mainly exist in a resting state and constantly monitor their microenvironment and survey neuronal and synaptic activity.Through the C1 q,C3 and CR3"Eat Me"and CD47 and SIRPα"Don't Eat Me"complement pathways,as well as other pathways such as CX3 CR1 signaling,resting microglia regulate synaptic pruning,a process crucial for the promotion of synapse formation and the regulation of neuronal activity and synaptic plasticity.By mediating synaptic pruning,resting microglia play an important role in the regulation of experience-dependent plasticity in the barrel cortex and visual cortex after whisker removal or monocular deprivation,and also in the regulation of learning and memory,including the modulation of memory strength,forgetfulness,and memory quality.As a response to brain injury,infection or neuroinflammation,microglia become activated and increase in number.Activated microglia change to an amoeboid shape,migrate to sites of inflammation and secrete proteins such as cytokines,chemokines and reactive oxygen species.These molecules released by microglia can lead to synaptic plasticity and learning and memory deficits associated with aging,Alzheimer's disease,traumatic brain injury,HIV-associated neurocognitive disorder,and other neurological or mental disorders such as autism,depression and post-traumatic stress disorder.With a focus mainly on recently published literature,here we reviewed the studies investigating the role of resting microglia in synaptic plasticity and learning and memory,as well as how activated microglia modulate disease-related plasticity and learning and memory deficits.By summarizing the function of microglia in these processes,we aim to provide an overview of microglia regulation of synaptic plasticity and learning and memory,and to discuss the possibility of microglia manipulation as a therapeutic to ameliorate cognitive deficits associated with aging,Alzheimer's disease,traumatic brain injury,HIV-associated neurocognitive disorder,and mental disorders.
文摘Aggression is a common behavioral strategy employed by animals to secure limited resources, but must be applied with restraint to limit potential costs including injury. How animals make the adap- tive decision to fight or flee is barely known. Here, we review our work on crickets that reveals the roles of biogenic amines, primarily octopamine (the insect analog of noradrenaline) and nitric oxide (NO). Using aminergic drugs, we found that amines are not essential for actually initiating aggres- sion. However, octopamine is necessary for mediating the aggression-promoting effects of poten- tially rewarding experiences including stimulation with a male antenna, physical exertion, winning, and resource possession. Hence, octopamine can be considered as the motivational component of aggression. Imposed handicaps that impede aggressive signaling revealed that the agonistic actions of an opponent perceived during fighting act to reduce aggression, and that crickets make the deci- sion to flee the moment the accumulated sum of such aversive experiences exceeds some critical level. Treatment with nitridergic drugs revealed that the impact of the opponent's aggressive actions is mediated by NO. NO acts to suppress aggression by promoting the tendency to flee and is primarily responsible for the depressed aggressiveness of subordinates after social defeat. Octopamine and dopamine can each restore aggression in subordinates, but only dopamine is necessary for normal recovery. The role of serotonin remains unclear, and is discussed. We conclude that octopamine and NO control the decision to fight or flee by mediating the effects of potentially rewarding and aversive experiences, respectively.
基金supported by grants from the National Natural Science Foundation of China(32130043 to X.Z.)the Scientific&Technological Innovation(STI)2030-Major Project(2022ZD0204900 to X.Z.)+1 种基金the National Natural Science Foundation of China(32400870 to Z.S.)the Fundamental Research Funds for the Central Universities(2243300002 to Z.S.).
文摘Critical periods(CPs)are defined as postnatal developmental windows during which brain circuits exhibit heightened sensitivity to altered experiences or sensory inputs,particularly during brain development in humans and animals.During the CP,experience-induced refinements of neural connections are crucial for establishing adaptive and mature brain functions,and aberrant CPs are often accompanied by many neurodevelopmental disorders(NDDs),including autism spectrum disorders and schizophrenia.Understanding neural mechanisms underlying the CP regulation is key to delineating the etiology of NDDs caused by abnormal postnatal neurodevelopment.Recent evidence from studies using innovative experimental tools has continuously revisited the inhibition-gating theory of CP to systematically elucidate the differential roles of distinct inhibitory circuits.Here,we provide a comprehensive review of classical experimental findings and emerging inhibitory-circuit regulation mechanisms of the CP,and further discuss how aberrant CP plasticity is associated with NDDs.