黄精多糖调控SIRT1/AMPK/PGC-1α信号通路改善H2O2诱导的HT22细胞氧化损伤

Regulation of SIRT1/AMPK/PGC-1α Signaling Pathway by Polygonatum Polysaccharide Improves H2O2-induced Oxidative Damage in HT22 Cells

关键词:  黄精多糖  氧化应激  AMPK  SIRT1  PGC-1a

Key words:  Polygonatum polysaccharides  oxidative injury  AMPK  SIRT1  PGC-1a

摘要:

目的 研究黄精多糖对H₂O₂诱导的HT22细胞氧化应激损伤及其对SIRT1/AMPK/PGC-1α信号通路关键信号分子的影响。方法 建立H₂O₂诱导HT22细胞氧化损伤模型，黄精多糖干预后，观察黄精多糖对HT22细胞活性乳酸脱氢酶（lactate dehydrogenase，LDH）释放的影响，检测超氧化物歧化酶（superoxide dismutase，SOD）活性、丙二醛（malondialdehyde，MDA）含量、还原型谷胱甘肽（glutathione，GSH）含量、线粒体呼吸链酶复合体Ⅰ活性、腺嘌呤核苷三磷酸（adenosine triphosphate，ATP）含量，Western blotting检测细胞中SIRT1、AMPK、p-AMPK及PGC-1α蛋白的表达。结果 与模型组相比，黄精多糖（100，200，400 μmicro；g·mL^-1）明显提高细胞活性（P<0.05或P<0.01），降低LDH释放（P<0.05或P<0.01），减少MDA的产生（P<0.05或P<0.01），增加SOD活力和GSH含量（P<0.05或P<0.01），可提高ATP含量及线粒体呼吸链酶复合体Ⅰ活性。此外，黄精多糖还能够上调细胞中SIRT1、p-AMPK及PGC-1α蛋白的表达。结论 黄精多糖能通过增强细胞内抗氧化活性，提高HT22细胞的存活率，改善线粒体功能，从而保护细胞抗氧化损伤，其作用机制与激活SIRT1/AMPK/PGC-1α信号通路有关。

Abstract:

OBJECTIVE To study the effects of Polygonatum polysaccharides on H₂O₂-induced oxidative injury in HT22 cells, and effect on key signaling molecules in SIRT1/AMPK/PGC-1α signaling pathway. METHODS The oxidative injury model of HT22 cells induced by H₂O₂ was established. The effect of Polygonatum polysaccharides on the cell viability and lactate dehydrogenase(LDH) release of HT22 cells were observed. The levels of antioxidant enzyme activities of superoxide dismutase(SOD), malondialdehyde(MDA) activity and glutathione(GSH) activity, mitochondrial respiratory chain enzyme complexes Ⅰ activity and adenosine triphosphate(ATP) were determined by respective kits. Meanwhile, Western blotting was used to detect the protein expression of SIRT1, AMPK, p-AMPK and PGC-1α. RESULTS Compared with the model group, Polygonatum polysaccharides(100, 200, 400 µg·mL^-1) could significantly enhance the cell vitality(P<0.05 or P<0.01), reduce the release of LDH(P<0.05 or P<0.01), reduce the production of MDA(P<0.05 or P<0.01), increase the activities of SOD and GSH(P<0.05 or P<0.01), increase the contents of ATP and the activity of mitochondrial respiratory chain enzyme complexes Ⅰ. In addition, SIRT1, p-AMPK and PGC-1α protein expressions in cells were up-regulated by Polygonatum polysaccharides. CONCLUSION Polygonatum polysaccharides can enhance the intracellular antioxidant activity to enhance the survival rate of HT22 cells, improve mitochondrial function, thus protect the cells from oxidative injury. And its mechanism is related to the activation of SIRT1/AMPK/PGC-1α signaling pathway.