General anesthesia severely affects the metabolites in the brain.Glycogen,principally stored in astrocytes and providing the short-term delivery of substrates to neurons,has been implicated as an affected molecule.How...General anesthesia severely affects the metabolites in the brain.Glycogen,principally stored in astrocytes and providing the short-term delivery of substrates to neurons,has been implicated as an affected molecule.However,whether glycogen plays a pivotal role in modulating anesthesia-arousal remains unclear.Here,we demonstrated that isoflurane-anesthetized mice exhibited dynamic changes in the glycogen levels in various brain regions.Glycogen synthase(GS)and glycogen phosphorylase(GP),key enzymes of glycogen metabolism,showed increased activity after isoflurane exposure.Upon blocking glycogenolysis with 1,4-dideoxy-1,4-imino-Darabinitol(DAB),a GP antagonist,we found a prolonged time of emergence from anesthesia and an enhancedδfrequency in the EEG(electroencephalogram).In addition,augmented expression of glycogenolysis genes in glycogen phosphorylase,brain(Pygb)knock-in(PygbH11/H11)mice resulted in delayed induction of anesthesia,a shortened emergence time,and a lower ratio of EEG-δ.Our findings revealed a role of brain glycogen in regulating anesthesiaarousal,providing a potential target for modulating anesthesia.展开更多
Myocardial ischemia/reperfusion injury can lead to severe brain injury.Glycogen synthase kinase 3 beta is known to be involved in myocardial ischemia/reperfusion injury and diabetes mellitus.However,the precise role o...Myocardial ischemia/reperfusion injury can lead to severe brain injury.Glycogen synthase kinase 3 beta is known to be involved in myocardial ischemia/reperfusion injury and diabetes mellitus.However,the precise role of glycogen synthase kinase 3 beta in myocardial ischemia/reperfusion injury-induced brain injury is unclear.In this study,we observed the effects of glycogen synthase kinase 3 beta on brain injury induced by myocardial ischemia/reperfusion injury in diabetic rats.Rat models of diabetes mellitus were generated via intraperitoneal injection of streptozotocin.Models of myocardial ischemia/reperfusion injury were generated by occluding the anterior descending branch of the left coronary artery.Post-conditioning comprised three cycles of ischemia/reperfusion.Immunohistochemical staining and western blot assays demonstrated that after 48 hours of reperfusion,the structure of the brain was seriously damaged in the experimental rats compared with normal controls.Expression of Bax,interleukin-6,interleukin-8,terminal deoxynucleotidyl transferase d UTP nick end labeling,and cleaved caspase-3 in the brain was significantly increased,while expression of Bcl-2,interleukin-10,and phospho-glycogen synthase kinase 3 beta was decreased.Diabetes mellitus can aggravate inflammatory reactions and apoptosis.Ischemic post-conditioning with glycogen synthase kinase 3 beta inhibitor lithium chloride can effectively reverse these changes.Our results showed that myocardial ischemic post-conditioning attenuated myocardial ischemia/reperfusion injury-induced brain injury by activating glycogen synthase kinase 3 beta.According to these results,glycogen synthase kinase 3 beta appears to be an important factor in brain injury induced by myocardial ischemia/reperfusion injury.展开更多
Decreased expression of brain-derived neurotrophic factor（BDNF） plays an important role in the pathogenesis of Alzheimer＇s disease, and a typical pathological change in Alzheimer＇s disease is neurofibrillary tangl...Decreased expression of brain-derived neurotrophic factor（BDNF） plays an important role in the pathogenesis of Alzheimer＇s disease, and a typical pathological change in Alzheimer＇s disease is neurofibrillary tangles caused by hyperphosphorylation of tau. An in vivo model of Alzheimer＇s disease was developed by injecting okadaic acid（2 μL） and exogenous BDNF（2 μL） into the hippocampi of adult male Wister rats. Spatial learning and memory abilities were assessed using the Morris water maze. The expression levels of protein phosphatase 2 A（PP2 A）, PP2 Ac-Yp307, p-tau（Thr231）, and p-tau（Ser396/404） were detected by western blot assay. The expression levels of BDNF, TrkB, and synaptophysin mRNA were measured by quantitative real-time polymerase chain reaction. Our results indicated that BDNF expression was suppressed in the hippocampus of OA-treated rats, which resulted in learning and memory deficits. Intra-hippocampal injection of BDNF attenuated this OA-induced cognitive impairment. Finally, our findings indicated an involvement of the PI3 K/GSK-3β/AKT pathway in the mechanism of BDNF in regulating cognitive function. These results indicate that BDNF has beneficial effect on Alzheimer＇s disease, and highlight the potential of BDNF as a drug target for treatment of Alzheimer＇s disease.展开更多
Transient brain ischemia has been shown to induce hyperphosphorylation of the micro- tubule-associated protein tau. To further determine the mechanisms underlying these processes, we investigated the interaction betwe...Transient brain ischemia has been shown to induce hyperphosphorylation of the micro- tubule-associated protein tau. To further determine the mechanisms underlying these processes, we investigated the interaction between tau, glycogen synthase kinase （GSK）-313 and protein phos- phatase 2A. The results confirmed that tau protein was dephosphorylated during brain ischemia; in addition, the activity of GSK-3β was increased and the activity of protein phosphatase 2A was de- creased. After reperfusion, tau protein was hyperphosphorylated, the activity of GSK-3β was de- creased and the activity of protein phosphatase 2A remained low. Importantly, the interaction of tau with GSK-3β and protein phosphatase 2A was altered during ischemia and reperfusion. Lithium chloride could affect tau phosphorylation by regulating the interaction of tau with GSK-3β and pro- tein phosphatase 2A, and improve learning and memory ability of rats after transient brain ischemia. The present study demonstrated that it was the interaction of tau with GSK-3β and protein phos- phatase 2A, rather than their individual activities, that dominates the phosphorylation of tau in tran- sient brain ischemia. Hyperphosphorylated tau protein may play an important role in the evolution of brain injury in ischemic stroke. The neuroprotective effects of lithium chloride partly depend on the inhibition of tau phosphorylation during transient brain ischemia.展开更多
【目的】观察电针百会、风府、双侧肾俞穴联合人脐带间充质干细胞(hUC-MSCs)移植对缺血性脑损伤大鼠的脑保护作用及机制。【方法】将40只SD大鼠随机分为正常组、模型组、移植组、联合组,每组10只。除正常组,其他各组大鼠建立脑缺血再灌...【目的】观察电针百会、风府、双侧肾俞穴联合人脐带间充质干细胞(hUC-MSCs)移植对缺血性脑损伤大鼠的脑保护作用及机制。【方法】将40只SD大鼠随机分为正常组、模型组、移植组、联合组,每组10只。除正常组,其他各组大鼠建立脑缺血再灌注损伤模型。在造模结束24 h后,移植组大鼠给予0.5 m L 2×10^(6)个hUC-MSCs细胞悬液一次性尾静脉植入,联合组在移植组治疗基础上,给予电针百会穴、风府穴、双侧肾俞穴,每次30 min,每日1次,连续针刺3周。治疗结束后,苏木素-伊红(HE)染色法观察海马组织病理形态,脱氧核糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)法观察脑组织细胞凋亡情况,免疫荧光法检测脑组织腺苷A2A受体(ADORA2A)表达,免疫组织化学法检测脑组织糖原合酶激酶3β(GSK-3β)、β-连环蛋白(β-catenin)表达,Western Blot法检测脑组织跨膜蛋白闭锁蛋白(Occludin)、胞质附着蛋白(ZO-1)表达。【结果】与正常组比较,模型组脑组织细胞凋亡率升高,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平升高,Occludin、ZO-1、β-catenin蛋白表达水平降低(P<0.05),HE染色结果显示,模型组海马组织结构明显异常;与模型组比较,移植组和联合组大鼠脑组织细胞凋亡率降低,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平降低,Occludin、ZO-1、β-catenin蛋白表达水平升高(P<0.05),海马组织病理程度明显减轻;与移植组比较,联合组脑组织细胞凋亡率降低,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平降低,Occludin、ZO-1、β-catenin蛋白表达水平升高(P<0.05)。【结论】电针百会、风府、双侧肾俞穴联合hUC-MSCs可改善缺血性脑损伤大鼠血脑屏障,抑制脑组织ADORA2A、GSK-3β表达,提高β-catenin表达,抑制脑组织细胞凋亡,起到脑保护作用,且作用效果优于单纯hUC-MSCs移植。展开更多
基金the Major Program of the National Natural Science Foundation of China(81590954)the International Cooperation and Exchange of the National Natural Science Foundation of China(81420108013)the State Key Program of National Natural Science Foundation of China(81730032)。
文摘General anesthesia severely affects the metabolites in the brain.Glycogen,principally stored in astrocytes and providing the short-term delivery of substrates to neurons,has been implicated as an affected molecule.However,whether glycogen plays a pivotal role in modulating anesthesia-arousal remains unclear.Here,we demonstrated that isoflurane-anesthetized mice exhibited dynamic changes in the glycogen levels in various brain regions.Glycogen synthase(GS)and glycogen phosphorylase(GP),key enzymes of glycogen metabolism,showed increased activity after isoflurane exposure.Upon blocking glycogenolysis with 1,4-dideoxy-1,4-imino-Darabinitol(DAB),a GP antagonist,we found a prolonged time of emergence from anesthesia and an enhancedδfrequency in the EEG(electroencephalogram).In addition,augmented expression of glycogenolysis genes in glycogen phosphorylase,brain(Pygb)knock-in(PygbH11/H11)mice resulted in delayed induction of anesthesia,a shortened emergence time,and a lower ratio of EEG-δ.Our findings revealed a role of brain glycogen in regulating anesthesiaarousal,providing a potential target for modulating anesthesia.
基金supported by the National Natural Science Foundation of China,No.81471844the Natural Science Foundation of Hubei Province of China,No.2016CFB167the Basic Scientific Research Foundation of Central Universities,No.2042017kf0147
文摘Myocardial ischemia/reperfusion injury can lead to severe brain injury.Glycogen synthase kinase 3 beta is known to be involved in myocardial ischemia/reperfusion injury and diabetes mellitus.However,the precise role of glycogen synthase kinase 3 beta in myocardial ischemia/reperfusion injury-induced brain injury is unclear.In this study,we observed the effects of glycogen synthase kinase 3 beta on brain injury induced by myocardial ischemia/reperfusion injury in diabetic rats.Rat models of diabetes mellitus were generated via intraperitoneal injection of streptozotocin.Models of myocardial ischemia/reperfusion injury were generated by occluding the anterior descending branch of the left coronary artery.Post-conditioning comprised three cycles of ischemia/reperfusion.Immunohistochemical staining and western blot assays demonstrated that after 48 hours of reperfusion,the structure of the brain was seriously damaged in the experimental rats compared with normal controls.Expression of Bax,interleukin-6,interleukin-8,terminal deoxynucleotidyl transferase d UTP nick end labeling,and cleaved caspase-3 in the brain was significantly increased,while expression of Bcl-2,interleukin-10,and phospho-glycogen synthase kinase 3 beta was decreased.Diabetes mellitus can aggravate inflammatory reactions and apoptosis.Ischemic post-conditioning with glycogen synthase kinase 3 beta inhibitor lithium chloride can effectively reverse these changes.Our results showed that myocardial ischemic post-conditioning attenuated myocardial ischemia/reperfusion injury-induced brain injury by activating glycogen synthase kinase 3 beta.According to these results,glycogen synthase kinase 3 beta appears to be an important factor in brain injury induced by myocardial ischemia/reperfusion injury.
文摘Decreased expression of brain-derived neurotrophic factor（BDNF） plays an important role in the pathogenesis of Alzheimer＇s disease, and a typical pathological change in Alzheimer＇s disease is neurofibrillary tangles caused by hyperphosphorylation of tau. An in vivo model of Alzheimer＇s disease was developed by injecting okadaic acid（2 μL） and exogenous BDNF（2 μL） into the hippocampi of adult male Wister rats. Spatial learning and memory abilities were assessed using the Morris water maze. The expression levels of protein phosphatase 2 A（PP2 A）, PP2 Ac-Yp307, p-tau（Thr231）, and p-tau（Ser396/404） were detected by western blot assay. The expression levels of BDNF, TrkB, and synaptophysin mRNA were measured by quantitative real-time polymerase chain reaction. Our results indicated that BDNF expression was suppressed in the hippocampus of OA-treated rats, which resulted in learning and memory deficits. Intra-hippocampal injection of BDNF attenuated this OA-induced cognitive impairment. Finally, our findings indicated an involvement of the PI3 K/GSK-3β/AKT pathway in the mechanism of BDNF in regulating cognitive function. These results indicate that BDNF has beneficial effect on Alzheimer＇s disease, and highlight the potential of BDNF as a drug target for treatment of Alzheimer＇s disease.
基金supported by the National High Technology Research and Development Program of China(863 Program),No.2012AA020905the Biological Industry Development Funds of Shenzhen,No.JC201005260093A+1 种基金the National Natural Science Foundation of China/Research Grants Council Joint Research Scheme,No.81161160570the National Natural Science Foundation of China,No.81171143the Tsinghua-Yue-Yuen Medical Sciences Fund
文摘Transient brain ischemia has been shown to induce hyperphosphorylation of the micro- tubule-associated protein tau. To further determine the mechanisms underlying these processes, we investigated the interaction between tau, glycogen synthase kinase （GSK）-313 and protein phos- phatase 2A. The results confirmed that tau protein was dephosphorylated during brain ischemia; in addition, the activity of GSK-3β was increased and the activity of protein phosphatase 2A was de- creased. After reperfusion, tau protein was hyperphosphorylated, the activity of GSK-3β was de- creased and the activity of protein phosphatase 2A remained low. Importantly, the interaction of tau with GSK-3β and protein phosphatase 2A was altered during ischemia and reperfusion. Lithium chloride could affect tau phosphorylation by regulating the interaction of tau with GSK-3β and pro- tein phosphatase 2A, and improve learning and memory ability of rats after transient brain ischemia. The present study demonstrated that it was the interaction of tau with GSK-3β and protein phos- phatase 2A, rather than their individual activities, that dominates the phosphorylation of tau in tran- sient brain ischemia. Hyperphosphorylated tau protein may play an important role in the evolution of brain injury in ischemic stroke. The neuroprotective effects of lithium chloride partly depend on the inhibition of tau phosphorylation during transient brain ischemia.
文摘【目的】观察电针百会、风府、双侧肾俞穴联合人脐带间充质干细胞(hUC-MSCs)移植对缺血性脑损伤大鼠的脑保护作用及机制。【方法】将40只SD大鼠随机分为正常组、模型组、移植组、联合组,每组10只。除正常组,其他各组大鼠建立脑缺血再灌注损伤模型。在造模结束24 h后,移植组大鼠给予0.5 m L 2×10^(6)个hUC-MSCs细胞悬液一次性尾静脉植入,联合组在移植组治疗基础上,给予电针百会穴、风府穴、双侧肾俞穴,每次30 min,每日1次,连续针刺3周。治疗结束后,苏木素-伊红(HE)染色法观察海马组织病理形态,脱氧核糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)法观察脑组织细胞凋亡情况,免疫荧光法检测脑组织腺苷A2A受体(ADORA2A)表达,免疫组织化学法检测脑组织糖原合酶激酶3β(GSK-3β)、β-连环蛋白(β-catenin)表达,Western Blot法检测脑组织跨膜蛋白闭锁蛋白(Occludin)、胞质附着蛋白(ZO-1)表达。【结果】与正常组比较,模型组脑组织细胞凋亡率升高,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平升高,Occludin、ZO-1、β-catenin蛋白表达水平降低(P<0.05),HE染色结果显示,模型组海马组织结构明显异常;与模型组比较,移植组和联合组大鼠脑组织细胞凋亡率降低,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平降低,Occludin、ZO-1、β-catenin蛋白表达水平升高(P<0.05),海马组织病理程度明显减轻;与移植组比较,联合组脑组织细胞凋亡率降低,脑组织ADORA2A阳性表达率及GSK-3β蛋白表达水平降低,Occludin、ZO-1、β-catenin蛋白表达水平升高(P<0.05)。【结论】电针百会、风府、双侧肾俞穴联合hUC-MSCs可改善缺血性脑损伤大鼠血脑屏障,抑制脑组织ADORA2A、GSK-3β表达,提高β-catenin表达,抑制脑组织细胞凋亡,起到脑保护作用,且作用效果优于单纯hUC-MSCs移植。
