基于p53线粒体凋亡通路研究绞股蓝皂苷改善奥沙利铂所致大鼠周围神经毒性的作用

Protective Effect of Gypenoside on Peripheral Nerve Toxicity Induced by Oxaliplatin in Rats Based on p53 Mediated Mitochondrial Apoptotic Pathway

目的:基于p53线粒体凋亡通路探讨绞股蓝皂苷(gypenoside,GPS)改善奥沙利铂所致大鼠周围神经毒性的可能作用机制。方法:选用雄性SD大鼠,随机分为5组:正常对照组、模型组、GPS低剂量组(50 mg/kg)、GPS中剂量组(100 mg/kg)和GPS高剂量组(200 mg/kg)。除正常对照组腹腔注射溶媒5%葡萄糖外,其他组均腹腔注射奥沙利铂4 mg/kg。除正常对照组和模型组外,GPS给药组分别给予不同浓度GPS灌胃。给药周期结束后处死大鼠,HE染色观察大鼠L4-5外周神经组织形态学变化,TUNEL检测L4-5脊髓神经元细胞凋亡情况。Western blot检测L4-5脊髓神经元凋亡相关蛋白细胞色素C(Cyt C)、Cleaved-caspase-9、Cleaved-caspase-3、Bax、Bcl-2和p-p53表达水平变化。结果:与正常对照组相比,模型组大鼠L4-5脊髓神经节部分神经元胞体缩小、出现核固缩、核膜轮廓模糊甚至消失、染色质凝聚、凋亡细胞显著增多,Bcl-2和蛋白表达水平显著下降,Cyt C、Cleaved-caspase-9、Cleaved-caspase-3、Bax和p-p53蛋白表达水平显著升高;而GPS可改善奥沙利铂所致L4-5脊髓神经元的形态异常,显著提高L4-5脊髓神经元Bcl-2蛋白表达水平,并降低Cyt C、Cleaved-caspase-9、Cleaved-caspase-3、Bax和p-p53蛋白表达水平。结论:GPS能显著改善奥沙利铂所致大鼠脊髓神经元细胞凋亡,其作用可能与抑制p53介导的线粒体凋亡通路有关。

Objective:To explore the possible molecular mechanism of gypenoside(GPS)on improvement of peripheral nerve toxicity induced by oxaliplatin in rats based on p53 mediated mitochondrial apoptotic pathway.Methods:Male SD rats were randomly divided into the control group,the model group,the low-,medium-and high-dose of GPS groups.Except of the control group,peripheral nerve toxicity rat models were established by intraperitoneal injection with oxaliplatin at a dose of 4 mg/kg.Meanwhile,different doses of GPS were given by gavage.The neurons morphology of L4-5 spinal cord was observed by HE staining,and the cell apoptosis was evaluated by TUNEL assay,and the protein levels of Cyt C,Cleaved-caspase-9,Cleaved-caspase-3,Bax,Bcl-2 and p-p53 were detected by western blot.Results:When compared with the control group,L4-5 spinal cord performed with significant morphology changes,including cell body shrinked,pyknotic nucleolus appeared,nuclear membrane contour blurred or even disappeared,chromatin condensed,and apoptotic cells increased in the model group.In addition,the protein expression of Bcl-2 was significantly reduced,consistent with increase of CytC,Cleaved-caspase-9,Cleaved-caspase-3,Bax and p-p53 in the model group.However,GPS reversed the oxaliplatin-induced morphology changes in L4-5 spinal cord,and inhibited cell apoptosis,accompanied by upregulation of Bcl-2,and downregulation of Bax,Cyt C,Cleaved-caspase-9,Cleaved-caspase-3 and p-p53 in L4-5 spinal cord.Conclusion:GPS can improve the apoptosis of rat spinal cord neurons induced by oxaliplatin,which may be related to the inhibition of p53-mediated mitochondrial apoptosis pathway.