目的评估miR-338-3p对氧糖剥夺(OGD)/复糖复氧(R)神经元损伤的影响及其机制。方法建立小鼠脑中动脉阻塞(MCAO)和神经元氧糖剥夺(OGD)模型;Western blot检测1 h MCAO/R 24、48和72 h小鼠脑梗死区周围皮质(n=5)和1 h OGD/R 0、6、12和24 ...目的评估miR-338-3p对氧糖剥夺(OGD)/复糖复氧(R)神经元损伤的影响及其机制。方法建立小鼠脑中动脉阻塞(MCAO)和神经元氧糖剥夺(OGD)模型;Western blot检测1 h MCAO/R 24、48和72 h小鼠脑梗死区周围皮质(n=5)和1 h OGD/R 0、6、12和24 h神经元(n=5)cPKCγ蛋白表达量;实时定量PCR检测cPKCγ及miR-338-3p mRNA水平;生物信息学分析cPKCγ3′UTR与miR-338-3p结合位点;噻唑兰(MTT)比色法和乳酸脱氢酶(LDH)法测定神经元(n=6)的存活率和凋亡率。采用免疫荧光与高内涵细胞成像分析技术(HCA)检测caspase-3蛋白表达情况。结果1 h MCAO/R 24、48和72 h小鼠脑梗死区周围皮层和1 h OGD/R 0、6、12和24 h神经元中cPKCγ蛋白及mRNA水平均明显上升(P<0.001);cPKCγ3′UTR存在1个miR-338-3p结合位点,miR-338-3p与cPKCγmRNA水平呈相反趋势;过表达miR-338-3p后1 h OGD/R 24 h神经元存活率下降(P<0.001),调亡率上升(P<0.001),caspase-3蛋白平均荧光强度值增高(P<0.001),抑制miR-338-3p后1 h OGD/R 24 h神经元存活率上升(P<0.001),调亡率下降(P<0.001),caspase-3蛋白平均荧光强度值降低(P<0.001)。结论miR-338-3p通过负性调节cPKCγ表达而使神经元存活率上升,凋亡率下降,减轻缺血神经元损伤。展开更多
Type 1 diabetes mellitus(T1DM)-induced cognitive dysfunction is common,but its underlying mechanisms are still poorly understood.In this study,we found that knockout of conventional protein kinase C(cPKC)γsignificant...Type 1 diabetes mellitus(T1DM)-induced cognitive dysfunction is common,but its underlying mechanisms are still poorly understood.In this study,we found that knockout of conventional protein kinase C(cPKC)γsignificantly increased the phosphorylation of Tau at Ser214 and neurofibrillary tangles,but did not affect the activities of GSK-3βand PP2A in the hippocampal neurons of T1DM mice.cPKCγdeficiency significantly decreased the level of autophagy in the hippocampal neurons of T1DM mice.Activation of autophagy greatly alleviated the cognitive impairment induced by cPKCγdeficiency in T1DM mice.Moreover,cPKCγdeficiency reduced the AMPK phosphorylation levels and increased the phosphorylation levels of mTOR in vivo and in vitro.The high glucose-induced Tau phosphorylation at Ser214 was further increased by the autophagy inhibitor and was significantly decreased by an mTOR inhibitor.In conclusion,these results indicated that cPKCγpromotes autophagy through the AMPK/mTOR signaling pathway,thus reducing the level of phosphorylated Tau at Ser214 and neurofibrillary tangles.展开更多
基金This work was supported by the Excellent Young Teachers Program of Ministry of Education of Chian Scientific Developing Program of Beijing Municipal Commission of Education (200KJ080+2 种基金 KM200310025100) Beijing Natural Science Foundation (7032005) Nati
文摘目的评估miR-338-3p对氧糖剥夺(OGD)/复糖复氧(R)神经元损伤的影响及其机制。方法建立小鼠脑中动脉阻塞(MCAO)和神经元氧糖剥夺(OGD)模型;Western blot检测1 h MCAO/R 24、48和72 h小鼠脑梗死区周围皮质(n=5)和1 h OGD/R 0、6、12和24 h神经元(n=5)cPKCγ蛋白表达量;实时定量PCR检测cPKCγ及miR-338-3p mRNA水平;生物信息学分析cPKCγ3′UTR与miR-338-3p结合位点;噻唑兰(MTT)比色法和乳酸脱氢酶(LDH)法测定神经元(n=6)的存活率和凋亡率。采用免疫荧光与高内涵细胞成像分析技术(HCA)检测caspase-3蛋白表达情况。结果1 h MCAO/R 24、48和72 h小鼠脑梗死区周围皮层和1 h OGD/R 0、6、12和24 h神经元中cPKCγ蛋白及mRNA水平均明显上升(P<0.001);cPKCγ3′UTR存在1个miR-338-3p结合位点,miR-338-3p与cPKCγmRNA水平呈相反趋势;过表达miR-338-3p后1 h OGD/R 24 h神经元存活率下降(P<0.001),调亡率上升(P<0.001),caspase-3蛋白平均荧光强度值增高(P<0.001),抑制miR-338-3p后1 h OGD/R 24 h神经元存活率上升(P<0.001),调亡率下降(P<0.001),caspase-3蛋白平均荧光强度值降低(P<0.001)。结论miR-338-3p通过负性调节cPKCγ表达而使神经元存活率上升,凋亡率下降,减轻缺血神经元损伤。
基金This work was supported by the Beijing Natural Science Foundation(7192016 and 7222064)the Scientific Research Common Program of Beijing Municipal Commission of Education(KM201910025029)the National Natural Science Foundation of China(82071539 and 31972911).
文摘Type 1 diabetes mellitus(T1DM)-induced cognitive dysfunction is common,but its underlying mechanisms are still poorly understood.In this study,we found that knockout of conventional protein kinase C(cPKC)γsignificantly increased the phosphorylation of Tau at Ser214 and neurofibrillary tangles,but did not affect the activities of GSK-3βand PP2A in the hippocampal neurons of T1DM mice.cPKCγdeficiency significantly decreased the level of autophagy in the hippocampal neurons of T1DM mice.Activation of autophagy greatly alleviated the cognitive impairment induced by cPKCγdeficiency in T1DM mice.Moreover,cPKCγdeficiency reduced the AMPK phosphorylation levels and increased the phosphorylation levels of mTOR in vivo and in vitro.The high glucose-induced Tau phosphorylation at Ser214 was further increased by the autophagy inhibitor and was significantly decreased by an mTOR inhibitor.In conclusion,these results indicated that cPKCγpromotes autophagy through the AMPK/mTOR signaling pathway,thus reducing the level of phosphorylated Tau at Ser214 and neurofibrillary tangles.
