基于Nrf2/HO-1通路探讨炮制降低雷公藤心毒性的作用机制

Preliminary exploration of detoxification mechanism of processing methods on cardiotoxicity induced by radix Tripterygium wilfordii in mice via Nrf2/HO-1 pathway

该研究考察了不同炮制方法对雷公藤诱导的心毒性的减毒作用,并基于核因子E2相关因子2(Nrf2)/血红素氧合酶1(HO-1)通路初探炮制减毒机制。雷公藤生品及其各炮制品(清炒品、金钱草炒炙品、绿豆炒炙品、白芍炒炙品、甘草炒炙品、醋炙品)均以2 g·kg^(-1)(以生药计)的剂量被灌胃给予小鼠连续28 d,末次给药后24 h,通过对小鼠血清生化指标的检测分析评价其减毒作用,通过蛋白免疫印迹法对心组织Nrf2/HO-1通路关键蛋白的表达、以及试剂盒法对部分氧化/抗氧化相关指标的检测分析,初探其减毒机制。雷公藤生品给药诱导小鼠血清肌酸激酶、乳酸脱氢酶、心脂质过氧化产物丙二醛的水平均显著升高(P<0.01),以及心Nrf2、HO-1蛋白表达水平及总超氧化物歧化酶、还原型谷胱甘肽、谷胱甘肽过氧化物酶、谷胱甘肽S-转移酶的水平均显著降低(P<0.01);而金钱草炒炙品、绿豆炒炙品、白芍炒炙品、甘草炒炙品、醋炙品给药后均在不同程度上逆转了雷公藤诱导的以上指标的异常(P<0.05,P<0.01),其中尤以金钱草炒炙品的逆转率为最高。综上,采用金钱草、绿豆、白芍、甘草分别炒炙,以及醋炙法炮制,均对雷公藤诱导的心毒性有减毒作用,且以金钱草炒炙法的减毒作用更佳,减毒机制可能与上调Nrf2所介导的心抗氧化防御并减轻氧化损伤有关。

This study aims to investigate the detoxification effects of different processing methods on the cardiotoxicity induced by radix Tripterygium wilfordii,and preliminarily explore the detoxification mechanism via the nuclear factor E2-related factor 2(Nrf2)/heme oxygenase 1(HO-1) pathway.The raw and processed products [stir-fried product,product stir-fried with Lysimachiae Herba(JQC),product stir-fried with Phaseoli Radiati Semen(LD),product stir-fried with Paeoniae Radix Alba(BS),product stir-fried with Glycyrrhizae Radix et Rhizoma(GC),and product stir-fried with vinegar(CZ)] of radix T.wilfordii were administrated to mice by gavage at a dose of 2 g·kg^(-1)(based on crude drugs) for 28 days.Twenty-four hours after the last administration,we measured the serum biochemical indexes of mice to evaluate the detoxification effect.Furthermore,we determined the expression of key proteins of Nrf2/HO-1 pathway in mouse heart tissue by Western blot and some oxidation/antioxidation-related indexes by corresponding kits to explore the detoxification mechanism.The administration of the raw product elevated the levels of serum creatine kinase,lactate dehydrogenase,and malondialdehyde,a product of cardiac lipid peroxidation(P<0.01),down-regulated the protein levels of Nrf2 and HO-1(P<0.01),and reduced the levels of total superoxide dismutase,glutathione,glutathione peroxidase,and glutathione S-transferase(P<0.01).However,after the administration of the products stir-fried with JQC,LD,BS,GC,and CZ,the abnormalities of the above indexes induced by the raw product were recovered(P<0.05 or P<0.01).In particular,the product stir-fried with JQC showed the best performance.Taken all together,the cardiotoxicity induced by radix T.wilfordii could be attenuated by stir-frying with JQC,LD,BS,GC,and CZ,and the stir-frying with JQC showed the best detoxification effect.The mechanism might be associated with the cardiac antioxidant defense and oxidative damage mitigation mediated by the up-regulated Nrf2.