Zhou Qian, Sun Yan, Tan Wangxiao, Liu Xiao, Qian Yuchen, Ma Xianghui, Wang Ting, Wang Xiaoying, Gao Xiumei
State Key Laboratory of Modern Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China.
College of Traditional Chinese Medicine, Tianjin University of Traditional Chinese Medicine, Tianjin, China.
PLoS One. 2017 Apr 28;12(4):e0176777. doi: 10.1371/journal.pone.0176777. eCollection 2017.
Long-term nitroglycerin (NTG) therapy causes tolerance to its effects attributing to increased oxidative stress and endothelial dysfunction. Shenmai injection (SMI), which is clinically used to treat cardiovascular diseases, consists of two herbal medicines, Ginseng Rubra and Ophiopogonjaponicas, and is reported to have antioxidant effects. The present study was designed to investigate the potential preventive effects of Shenmai injection on development of nitroglycerin-induced tolerance. The present study involves both in vivo and in vitro experiments to investigate nitroglycerin-induced tolerance. We examined the effect of Shenmai injection on the cardiovascular oxidative stress by measuring the serum levels of malondialdehyde (MDA) and superoxide dismutase (SOD). Endothelial dysfunction was determined by an endothelium-dependent vasorelaxation method in aortic rings and NOS activity. Inhibition of the cGMP/cGK-I signalling pathway was determined from released serum levels of cGMP and the protein expression levels of sGC, cGK-I, PDE1A and P-VASP by western blot. Here, we showed that SMI ameliorated the decrease in AV Peak Vel, the attenuation in the vasodilation response to nitroglycerin and endothelial dysfunction. SMI also reduced the cardiovascular oxidative stress by reducing the release of MDA and increasing the activity of SOD. Shenmai injection further ameliorated inhibition of the cGMP/cGK-I signalling pathway triggered by nitroglycerin-induced tolerance through up-regulating the protein expression of sGC, cGK-I, and P-VASP and down- regulating the proteins expression of PDE1A. In vitro studies showed that Shenmai injection could recover the attenuated vasodilation response to nitroglycerin following incubation (of aortic rings) with nitroglycerin via activating the enzymes of sGC and cGK-I. Therefore, we conclude that Shenmai injection could prevent NTG nitroglycerin-induced tolerance at least in part by decreasing the cardiovascular oxidative stress, meliorating the endothelial dysfunction and ameliorating the inhibition of the cGMP/cGK-I signalling pathway. These findings indicate the potential of Shenmai injection (SMI) as a promising medicine for preventing the development of nitroglycerin-induced tolerance.
长期使用硝酸甘油（NTG）治疗会导致对其作用产生耐受性，这归因于氧化应激增加和内皮功能障碍。参麦注射液（SMI）临床上用于治疗心血管疾病，由两种草药红参和麦冬组成，据报道具有抗氧化作用。本研究旨在探讨参麦注射液对硝酸甘油诱导的耐受性发展的潜在预防作用。本研究涉及体内和体外实验以研究硝酸甘油诱导的耐受性。我们通过测量血清丙二醛（MDA）和超氧化物歧化酶（SOD）水平来检测参麦注射液对心血管氧化应激的影响。通过主动脉环中内皮依赖性血管舒张方法和一氧化氮合酶（NOS）活性来确定内皮功能障碍。通过检测血清中环鸟苷酸（cGMP）释放水平以及通过蛋白质印迹法检测可溶性鸟苷酸环化酶（sGC）、蛋白激酶G-I（cGK-I）、磷酸二酯酶1A（PDE1A）和磷酸化血管舒张刺激蛋白（P-VASP）的蛋白表达水平来确定cGMP/cGK-I信号通路的抑制情况。在此，我们表明参麦注射液改善了主动脉峰值流速（AV Peak Vel）的降低、对硝酸甘油血管舒张反应的减弱以及内皮功能障碍。参麦注射液还通过减少MDA释放和增加SOD活性来降低心血管氧化应激。参麦注射液通过上调sGC、cGK-I和P-VASP的蛋白表达以及下调PDE1A的蛋白表达，进一步改善了由硝酸甘油诱导的耐受性引发的cGMP/cGK-I信号通路的抑制。体外研究表明，参麦注射液可通过激活sGC和cGK-I酶，使（主动脉环）与硝酸甘油孵育后对硝酸甘油减弱的血管舒张反应恢复。因此，我们得出结论，参麦注射液至少部分地通过降低心血管氧化应激,改善内皮功能障碍以及改善对cGMP/cGK-I信号通路的抑制来预防硝酸甘油诱导的耐受性。这些发现表明参麦注射液（SMI）作为一种有前景的药物在预防硝酸甘油诱导的耐受性发展方面具有潜力。
