苦参素通过p38/JNK信号途径对海马神经元凋亡的影响(1)
[摘要] 探讨苦参素(oxymatrine，OMT)对海马神经元凋亡的影响及其机制。采用MTT法测定OMT对海马神经元存活率的影响；生物化学法测定OMT对LPS诱导的海马神经元乳酸脱氢酶(lactate dehydrogenase，LDH)释放率的影响；Hochest 33342染色观察海马神经元凋亡形态；实时定量PCR(Real-time quantitative PCR，RT-qPCR)方法检测海马神经元中Bax，Bcl-2，Caspase-3 mRNA的表达；蛋白免疫印迹法(Western blot，WB)检测海马神经元中p38，p-p38，JNK，p-JNK，Bax，Bcl-2和Caspase-3的表达。结果发现，不同剂量的OMT(0.37～6.0 g·L-1)和海马神经元共培养24 h，海马神经元生长状态良好；LPS刺激后，海马神经元LDH释放率增加(P<0.01)，JNK和p38的磷酸化水平明显增加(P<0.01)，Bax/Bcl-2的比例及Caspase-3的表达上调(P<0.01)，海马神经元凋亡增加。OMT预处理后，能明显降低海马神经元经LPS刺激后的LDH释放(P<0.05或P<0.01)，减少p38和JNK磷酸化水平，降低Bax/Bcl-2的比例及Caspase-3的表达(P<0.01)，海马神经元凋亡减少。综上，OMT能降低经LPS激活的p38和JNK磷酸化水平，下调Bax/Bcl-2的比例和Caspase-3的表达，从而抑制海马神经元凋亡。OMT通过p38/JNK信号途径抑制海马神经元的凋亡。
, 百拇医药
[关键词] 苦参素； 海马神经元； 细胞凋亡； p38/JNK
[Abstract] To investigate the effect and mechanism of oxymatrine(OMT) on hippocampal neurons apoptosis. Effect of OMT on survival of hippocampal neurons was measured by MTT.Effect of OMT on LPS-induced lactate dehydrogenase(LDH) release rate in hippocampal neurons was measured by biochemical methods. Hoechst 33342 staining was used to observe the apoptotic morphology of hippocampal neurons.The mRNA expression levels of Bax， Bcl-2， and Caspase-3 were detected by Real-time quantitative PCR(RT-qPCR)， and the protein expression levels of p38， p-p38， JNK， p-JNK， Bax， Bcl-2 and Caspase-3 were detected by Western blot.The results showed that， hippocampal neurons all grew well after treatment by different doses (0.37-6.0 g·L-1) of OMT for 24 h. Stimulation from LPS increased the release of LDH(P<0.01)， improved the JNK and p38 phosphorylation levels(P<0.01)， increased the proportion of Bax/Bcl-2 and the expression of Caspase-3(P<0.01)， and promoted the apoptosis of hippocampal neurons. OMT pretreatment could significantly reduce the release of LDH induced by LPS stimulation(P<0.05 or P<0.01)， reduce the p38 and JNK phosphorylation， decrease the expression of Caspase-3 and Bax/Bcl-2(P<0.01)， and diminish the apoptosis of hippocampal neurons.In conclusion， OMT could reduce the LPS-induced phosphorylation of p38 and JNK， down-regulate the Bax/Bcl-2 ratio and expression of Caspase-3， thus inhibiting apoptosis of hippocampal neurons. The mechanism may be associated with p38/JNK signaling pathway.
[Key words] oxymatrine； hippocampal neurons； apoptosis； p38/JNK
神經退行性疾病(neurodegenerative disease，ND)是一类慢性、进行性神经系统疾病，神经细胞退行性病变是它们的共同特点。在大多数ND中，尤其是阿尔茨海默病(Alzheimer′s disease，AD) 特征性病理变化之一是脑内神经元数目明显减少，以海马区和基底前脑受累最为严重，神经元减少平均可达47%。近年来认为细胞凋亡(apoptosis)是引起AD神经元数目减少的重要原因[1-3]。, 百拇医药(蔡艳 蒋伟 周爱玲 赵敏 徐玲)
, 百拇医药
[关键词] 苦参素； 海马神经元； 细胞凋亡； p38/JNK
[Abstract] To investigate the effect and mechanism of oxymatrine(OMT) on hippocampal neurons apoptosis. Effect of OMT on survival of hippocampal neurons was measured by MTT.Effect of OMT on LPS-induced lactate dehydrogenase(LDH) release rate in hippocampal neurons was measured by biochemical methods. Hoechst 33342 staining was used to observe the apoptotic morphology of hippocampal neurons.The mRNA expression levels of Bax， Bcl-2， and Caspase-3 were detected by Real-time quantitative PCR(RT-qPCR)， and the protein expression levels of p38， p-p38， JNK， p-JNK， Bax， Bcl-2 and Caspase-3 were detected by Western blot.The results showed that， hippocampal neurons all grew well after treatment by different doses (0.37-6.0 g·L-1) of OMT for 24 h. Stimulation from LPS increased the release of LDH(P<0.01)， improved the JNK and p38 phosphorylation levels(P<0.01)， increased the proportion of Bax/Bcl-2 and the expression of Caspase-3(P<0.01)， and promoted the apoptosis of hippocampal neurons. OMT pretreatment could significantly reduce the release of LDH induced by LPS stimulation(P<0.05 or P<0.01)， reduce the p38 and JNK phosphorylation， decrease the expression of Caspase-3 and Bax/Bcl-2(P<0.01)， and diminish the apoptosis of hippocampal neurons.In conclusion， OMT could reduce the LPS-induced phosphorylation of p38 and JNK， down-regulate the Bax/Bcl-2 ratio and expression of Caspase-3， thus inhibiting apoptosis of hippocampal neurons. The mechanism may be associated with p38/JNK signaling pathway.
[Key words] oxymatrine； hippocampal neurons； apoptosis； p38/JNK
神經退行性疾病(neurodegenerative disease，ND)是一类慢性、进行性神经系统疾病，神经细胞退行性病变是它们的共同特点。在大多数ND中，尤其是阿尔茨海默病(Alzheimer′s disease，AD) 特征性病理变化之一是脑内神经元数目明显减少，以海马区和基底前脑受累最为严重，神经元减少平均可达47%。近年来认为细胞凋亡(apoptosis)是引起AD神经元数目减少的重要原因[1-3]。, 百拇医药(蔡艳 蒋伟 周爱玲 赵敏 徐玲)