目的观察小鼠学习记忆能力及其海马区突触功能相关蛋白脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及GluA1表达的增龄性变化。方法观察10周龄(青年组)和21...目的观察小鼠学习记忆能力及其海马区突触功能相关蛋白脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及GluA1表达的增龄性变化。方法观察10周龄(青年组)和21月龄(老年组)C57BL/6雄性小鼠Morris水迷宫训练和测试表现,并应用Western blot技术检测两组小鼠海马区BDNF、PSD95、GluA1的蛋白表达。结果与青年组相比,老年组小鼠水迷宫测试中的学习记忆能力明显下降(P均<0.05),其海马区总蛋白BDNF、PSD95、GluA1的表达量均显著下降(P均<0.05),海马区膜蛋白GluA1的表达量也明显下降(P<0.05)。结论老年小鼠学习记忆能力下降伴随着海马区突触功能相关蛋白BDNF、PSD95、GluA1表达的一致下降。展开更多
Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitizat...Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitization （a specific form of synaptic plasticity） that is associated with persistent pain. Recent studies have shown that peripheral inflammation drives changes in ct-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor （AMPAR） subunit trafficking in the dorsal horn and that such changes contribute to the hypersensitivity that underlies persistent pain. Here, we review current evi- dence to illustrate how spinal cord AMPARs participate in the dorsal hom central sensitization associated with persistent pain. Understanding these mechanisms may allow the development of novel therapeutic strategies for treating persistent pain.展开更多
钙/钙调蛋白依赖的蛋白激酶Ⅱ(Ca2+/calmodulin-dependent protein kinase Ⅱ,CaMKⅡ)在脑内兴奋性突触部位丰富表达。通过催化谷氨酸受体和众多突触蛋白磷酸化,CaMKⅡ调节磷酸化蛋白在基础或细胞兴奋时的转运、分布和功能。谷氨酸NMDA...钙/钙调蛋白依赖的蛋白激酶Ⅱ(Ca2+/calmodulin-dependent protein kinase Ⅱ,CaMKⅡ)在脑内兴奋性突触部位丰富表达。通过催化谷氨酸受体和众多突触蛋白磷酸化,CaMKⅡ调节磷酸化蛋白在基础或细胞兴奋时的转运、分布和功能。谷氨酸NMDA受体是CaMKⅡ的直接底物,有证据表明CaMKⅡ直接与NMDA受体胞内C末端相互结合,催化一特定丝氨酸(S1303)的磷酸化。CaMKⅡ也加强谷氨酸AMPA受体的磷酸化,通过磷酸化AMPA受体C末端特定的丝氨酸(S831),CaMKⅡ增强AMPA受体的功能。此外,CaMKⅡ可与代谢型谷氨酸受体mGluR1亚型的胞内C末端结合,促进一特定苏氨酸(T871)的磷酸化,从而促进受体兴奋后脱敏。CaMKⅡ在正常状态下与mGluR5受体结合以储存于突触内,刺激mGluR5受体时,CaMKⅡ与mGluR5受体分离,转运至NMDA受体,以介导mGluR5信号对NMDA受体的增强作用。总之,CaMKⅡ与谷氨酸受体相互作用,改变受体磷酸化水平,参与受体的数量和功能以及突触传导活动的调节。展开更多
Background Ribosomal protein S6 kinase 1(S6K1)is a serine-threonine kinase that has two main isoforms:p70S6K(70-kDa isoform)and p85S6K(85-kDa isoform).p70S6K,with its upstream mammalian target of rapamycin(mTOR),has b...Background Ribosomal protein S6 kinase 1(S6K1)is a serine-threonine kinase that has two main isoforms:p70S6K(70-kDa isoform)and p85S6K(85-kDa isoform).p70S6K,with its upstream mammalian target of rapamycin(mTOR),has been shown to be involved in learning and memory and participate in the pathophysiology of Alzheimer’s dis-ease(AD).However,the function of p85S6K has long been neglected due to its high similarity to p70S6k.The role of p85S6K in learning and memory is still largely unknown.Methods We fractionated the postsynaptic densities to illustrate the differential distribution of p85S6K and p70S6K.Coimmunoprecipitation was performed to unveil interactions between p85S6K and the GluA1 subunit of AMPA receptor.The roles of p85S6K in synaptic targeting of GluA1 and learning and memory were evaluated by specific knockdown or overexpression of p85S6K followed by a broad range of methodologies including immunofluorescence,Western blot,in situ proximity ligation assay,morphological staining and behavioral examination.Further,the expression level of p85S6K was measured in brains from AD patients and AD model mice.Results p85S6K,but not p70S6K,was enriched in the postsynaptic densities.Moreover,knockdown of p85S6K resulted in defective spatial and recognition memory.In addition,p85S6K could interact with the GluA1 subunit of AMPA receptor through synapse-associated protein 97 and A-kinase anchoring protein 79/150.Mechanistic studies demonstrated that p85S6K could directly phosphorylate GluA1 at Ser845 and increase the amount of GluA1 in syn-apses,thus sustaining synaptic function and spine densities.Moreover,p85S6K was found to be specifically decreased in the synaptosomal compartment in the brains of AD patients and AD mice.Overexpression of p85S6K ameliorated the synaptic deficits and cognitive impairment in transgenic AD model mice.Conclusions These results strongly imply a significant role for p85S6K in maintaining synaptic and cognitive function by interacting with GluA1.The findings provide an insight into the r展开更多
Adolescent alcohol abuse is a substantive public health problem that has been the subject of intensive study in recent years.Despite reports of a wide range of effects of adolescent intermittent ethanol(AIE)exposure o...Adolescent alcohol abuse is a substantive public health problem that has been the subject of intensive study in recent years.Despite reports of a wide range of effects of adolescent intermittent ethanol(AIE)exposure on brain and behavior,little is known about the mechanisms that may underlie those effects,and even less about treatments that might reverse them.Recent studies from our laboratory have indicated that AIE produced enduring changes in astrocyte function and synaptic activity in the hippocampal formation,suggesting the possibility of an alteration in astrocyte-neuronal connectivity and function.We utilized astrocyte-specific,membrane restricted viral labeling paired with immunohistochemistry to perform confocal single cell astrocyte imaging,three-dimensional reconstruction,and quantification of astrocyte morphology in hippocampal area CA1 from adult rats after AIE.Additionally,we assessed the colocalization of astrocyte plasma membrane labeling with immunoreactivity for AMPA-(α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)glutamate receptor 1,an AMPA receptor subunit and established neuronal marker of excitatory synapses,as a metric of astrocyte-synapse proximity.AIE significantly reduced the colocalization of the astrocyte plasma membrane with synaptic marker puncta in adulthood.This is striking in that it suggests not only an alteration of the physical association of astrocytes with synapses by AIE,but one that lasts into adulthood-well after the termination of alcohol exposure.Perhaps even more notable,the AIE-induced reduction of astrocyte-synapse interaction was reversed by sub-chronic treatment with the clinically used agent,gabapentin(Neurontin),in adulthood.This suggests that a medication in common clinical use may have the potential to reverse some of the enduring effects of adolescent alcohol exposure on brain function.All animal experiments conducted were approved by the Duke University Institutional Animal Care and Use Committee(Protocol Registry Number A159-18-07)on July 27,2018.展开更多
Objective:To explore the changes of cannabinoid receptor(CB1)and AMPA receptor subunit GluA1 in the medial prefrontal cortex(mPFC)of depression model rats induced by chronic unpredictable mild stress(CUMS).Methods:30 ...Objective:To explore the changes of cannabinoid receptor(CB1)and AMPA receptor subunit GluA1 in the medial prefrontal cortex(mPFC)of depression model rats induced by chronic unpredictable mild stress(CUMS).Methods:30 rats were randomly divided into three groups.The three-week model group was given a three-week CUMS model,the four-week model group was given a four-week CUMS model,and the control group was given no treatment.The behavior of rats were detected in each group,and the expression of CB1 and GluA1 protein in synaptosomes in mPFC brain region was detected by Western blot.Results:Compared with the control group,the surcose preference decreased,the feeding latency increased in the novel inhibition feeding test,and the immobility time increased in the forced swimming test in the four-week model group.However,after three weeks of CUMS,there was no obvious change in the behavior of rats compared with the control group,suggesting that four-week model of CUMS was successful.CUMS can reduce the expression level of CB1 and GluA1 protein in synaptosomes of mPFC brain area in four-week model group(P<0.05),but there was no significant difference between three-week model group and control group.Conclusion:Four-week CUMS was more likely to lead to depressive-like behavior in rats,which may be closely related to the expression of CB1 and GluA1 in mPFC.展开更多
文摘目的观察小鼠学习记忆能力及其海马区突触功能相关蛋白脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)、突触后致密蛋白95(postsynaptic density protein 95,PSD95)及GluA1表达的增龄性变化。方法观察10周龄(青年组)和21月龄(老年组)C57BL/6雄性小鼠Morris水迷宫训练和测试表现,并应用Western blot技术检测两组小鼠海马区BDNF、PSD95、GluA1的蛋白表达。结果与青年组相比,老年组小鼠水迷宫测试中的学习记忆能力明显下降(P均<0.05),其海马区总蛋白BDNF、PSD95、GluA1的表达量均显著下降(P均<0.05),海马区膜蛋白GluA1的表达量也明显下降(P<0.05)。结论老年小鼠学习记忆能力下降伴随着海马区突触功能相关蛋白BDNF、PSD95、GluA1表达的一致下降。
文摘目的观察电针“百会”“神庭”对血管性痴呆(vascular dementia,VD)大鼠学习和记忆功能的影响,并从突触结构及突触相关蛋白表达水平的角度揭示其作用机制。方法将35只雄性SD大鼠随机分为假手术组、模型组、电针穴位组、电针非穴位组和奥拉西坦组,每组7只。采用改良双侧颈动脉结扎模型,电针穴位组大鼠选择“百会”“神庭”两穴治疗,电针非穴位组大鼠选择固定非穴位刺激,每次电针30 min,每日1次,连续干预14 d;奥拉西坦组大鼠选择腹腔注射奥拉西坦,50 mg/kg,每日1次,连续14 d。采用Morris水迷宫检测各组大鼠学习和空间记忆能力;透射电子显微镜观察各组大鼠海马CA1区突触结构;Western blot检测各组大鼠海马突触后致密蛋白95(postsynaptic density protein 95,PSD95)、GluA1、GluN2B和磷酸化GluN2B蛋白表达水平。结果与假手术组比较,模型组大鼠学习期逃避潜伏时间延长,测试期跨越平台次数减少,目标象限停留时间显著缩短,大脑质量显著增加,海马CA1区突触结构数明显减少,海马PSD95、GluA1、GluN2B和磷酸化GluN2B蛋白表达水平均显著降低,差异均有统计学意义(P<0.05);与模型组比较,电针穴位组大鼠的学习期逃避潜伏时间缩短,测试期跨越平台次数增加,目标象限停留时间延长,大脑质量降低,CA1区突触结构数增多,海马PSD95、GluA1、GluN2B和磷酸化GluN2B蛋白表达水平增加,差异均有统计学意义(P<0.05)。结论电针“百会”“神庭”能改善VD大鼠的学习记忆功能,改变海马突触结构,分子机制可能和增加突触蛋白PSD95、GluA1和GluN2B的蛋白表达水平相关。
基金supported by grants from the National Institutes of Health (NS058886 and NS072206)Rita Allen Foundation+1 种基金Mr. David Koch and the Patrick C. Walsh Prostate Cancer Research Fundthe Blaustein Pain Research Fund
文摘Activity-dependent postsynaptic receptor trafficking is critical for long-term synaptic plasticity in the brain, but it is unclear whether this mechanism actually mediates the spinal cord dorsal hom central sensitization （a specific form of synaptic plasticity） that is associated with persistent pain. Recent studies have shown that peripheral inflammation drives changes in ct-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor （AMPAR） subunit trafficking in the dorsal horn and that such changes contribute to the hypersensitivity that underlies persistent pain. Here, we review current evi- dence to illustrate how spinal cord AMPARs participate in the dorsal hom central sensitization associated with persistent pain. Understanding these mechanisms may allow the development of novel therapeutic strategies for treating persistent pain.
文摘钙/钙调蛋白依赖的蛋白激酶Ⅱ(Ca2+/calmodulin-dependent protein kinase Ⅱ,CaMKⅡ)在脑内兴奋性突触部位丰富表达。通过催化谷氨酸受体和众多突触蛋白磷酸化,CaMKⅡ调节磷酸化蛋白在基础或细胞兴奋时的转运、分布和功能。谷氨酸NMDA受体是CaMKⅡ的直接底物,有证据表明CaMKⅡ直接与NMDA受体胞内C末端相互结合,催化一特定丝氨酸(S1303)的磷酸化。CaMKⅡ也加强谷氨酸AMPA受体的磷酸化,通过磷酸化AMPA受体C末端特定的丝氨酸(S831),CaMKⅡ增强AMPA受体的功能。此外,CaMKⅡ可与代谢型谷氨酸受体mGluR1亚型的胞内C末端结合,促进一特定苏氨酸(T871)的磷酸化,从而促进受体兴奋后脱敏。CaMKⅡ在正常状态下与mGluR5受体结合以储存于突触内,刺激mGluR5受体时,CaMKⅡ与mGluR5受体分离,转运至NMDA受体,以介导mGluR5信号对NMDA受体的增强作用。总之,CaMKⅡ与谷氨酸受体相互作用,改变受体磷酸化水平,参与受体的数量和功能以及突触传导活动的调节。
基金supported by the National Natural Science Foundation of China(81802840,81473217)Shanghai Natural Science Foundation(20ZR1430100)Shanghai High Level Local University Construction Project(PT21002).
文摘Background Ribosomal protein S6 kinase 1(S6K1)is a serine-threonine kinase that has two main isoforms:p70S6K(70-kDa isoform)and p85S6K(85-kDa isoform).p70S6K,with its upstream mammalian target of rapamycin(mTOR),has been shown to be involved in learning and memory and participate in the pathophysiology of Alzheimer’s dis-ease(AD).However,the function of p85S6K has long been neglected due to its high similarity to p70S6k.The role of p85S6K in learning and memory is still largely unknown.Methods We fractionated the postsynaptic densities to illustrate the differential distribution of p85S6K and p70S6K.Coimmunoprecipitation was performed to unveil interactions between p85S6K and the GluA1 subunit of AMPA receptor.The roles of p85S6K in synaptic targeting of GluA1 and learning and memory were evaluated by specific knockdown or overexpression of p85S6K followed by a broad range of methodologies including immunofluorescence,Western blot,in situ proximity ligation assay,morphological staining and behavioral examination.Further,the expression level of p85S6K was measured in brains from AD patients and AD model mice.Results p85S6K,but not p70S6K,was enriched in the postsynaptic densities.Moreover,knockdown of p85S6K resulted in defective spatial and recognition memory.In addition,p85S6K could interact with the GluA1 subunit of AMPA receptor through synapse-associated protein 97 and A-kinase anchoring protein 79/150.Mechanistic studies demonstrated that p85S6K could directly phosphorylate GluA1 at Ser845 and increase the amount of GluA1 in syn-apses,thus sustaining synaptic function and spine densities.Moreover,p85S6K was found to be specifically decreased in the synaptosomal compartment in the brains of AD patients and AD mice.Overexpression of p85S6K ameliorated the synaptic deficits and cognitive impairment in transgenic AD model mice.Conclusions These results strongly imply a significant role for p85S6K in maintaining synaptic and cognitive function by interacting with GluA1.The findings provide an insight into the r
基金supported by the National Institute on Alcohol Abuse and Alcoholism(NIAAA)Neurobiology of Adolescent Drinking In Adulthood(NADIA)Grant#2U01AA019925(to HSS)the National Institute on Alcohol Abuse and Alcoholism(NIAAA)R00AA022651(to TAW)the National Institute on Drug Abuse(NIDA)R01DA041455(to KJR)
文摘Adolescent alcohol abuse is a substantive public health problem that has been the subject of intensive study in recent years.Despite reports of a wide range of effects of adolescent intermittent ethanol(AIE)exposure on brain and behavior,little is known about the mechanisms that may underlie those effects,and even less about treatments that might reverse them.Recent studies from our laboratory have indicated that AIE produced enduring changes in astrocyte function and synaptic activity in the hippocampal formation,suggesting the possibility of an alteration in astrocyte-neuronal connectivity and function.We utilized astrocyte-specific,membrane restricted viral labeling paired with immunohistochemistry to perform confocal single cell astrocyte imaging,three-dimensional reconstruction,and quantification of astrocyte morphology in hippocampal area CA1 from adult rats after AIE.Additionally,we assessed the colocalization of astrocyte plasma membrane labeling with immunoreactivity for AMPA-(α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)glutamate receptor 1,an AMPA receptor subunit and established neuronal marker of excitatory synapses,as a metric of astrocyte-synapse proximity.AIE significantly reduced the colocalization of the astrocyte plasma membrane with synaptic marker puncta in adulthood.This is striking in that it suggests not only an alteration of the physical association of astrocytes with synapses by AIE,but one that lasts into adulthood-well after the termination of alcohol exposure.Perhaps even more notable,the AIE-induced reduction of astrocyte-synapse interaction was reversed by sub-chronic treatment with the clinically used agent,gabapentin(Neurontin),in adulthood.This suggests that a medication in common clinical use may have the potential to reverse some of the enduring effects of adolescent alcohol exposure on brain function.All animal experiments conducted were approved by the Duke University Institutional Animal Care and Use Committee(Protocol Registry Number A159-18-07)on July 27,2018.
基金National Natural Science Foundation of China(No.81803857)Autonomous Subject of Beijing University of Chinese Medicine(No.2018-JYBZZ-XJSJJ002)。
文摘Objective:To explore the changes of cannabinoid receptor(CB1)and AMPA receptor subunit GluA1 in the medial prefrontal cortex(mPFC)of depression model rats induced by chronic unpredictable mild stress(CUMS).Methods:30 rats were randomly divided into three groups.The three-week model group was given a three-week CUMS model,the four-week model group was given a four-week CUMS model,and the control group was given no treatment.The behavior of rats were detected in each group,and the expression of CB1 and GluA1 protein in synaptosomes in mPFC brain region was detected by Western blot.Results:Compared with the control group,the surcose preference decreased,the feeding latency increased in the novel inhibition feeding test,and the immobility time increased in the forced swimming test in the four-week model group.However,after three weeks of CUMS,there was no obvious change in the behavior of rats compared with the control group,suggesting that four-week model of CUMS was successful.CUMS can reduce the expression level of CB1 and GluA1 protein in synaptosomes of mPFC brain area in four-week model group(P<0.05),but there was no significant difference between three-week model group and control group.Conclusion:Four-week CUMS was more likely to lead to depressive-like behavior in rats,which may be closely related to the expression of CB1 and GluA1 in mPFC.
