Chen He-Ping, Liao Zhang-Ping, Huang Qi-Ren, He Ming
Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang, PR China.
Eur J Pharmacol. 2009 Jan 28;603(1-3):86-92. doi: 10.1016/j.ejphar.2008.12.003. Epub 2008 Dec 9.
Development of intracellular calcium overload is an important pathophysiological factor in myocardial ischemia/reperfusion or anoxia/reoxygenation injury. Recent studies have shown that Sodium Ferulate (SF) stimulates nitric oxide (NO) production and exerts a cardioprotective effect in the ischemia-reperfused heart. However, it has not been determined whether the cardioprotection of SF is associated with suppression of Ca(2+) overload via NO/cyclic GMP (cGMP)/cGMP-dependent protein kinase (PKG) pathway. In this work, after cardiomyocytes were incubated with 100, 200, 400, or 800 microM SF for 3 h, anoxia/reoxygenation injury was induced and intracellular Ca(2+) concentration, NO synthase (NOS) activity, guanylate cyclase activity, NO, and cGMP formation were measured appropriately. The results showed that treatment with SF concentration-dependently inhibited calcium overload induced by anoxia/reoxygenation. We also demonstrated that SF (100-800 microM) concentration dependently enhanced NO and cGMP formation through increasing NOS activity and guanylate cyclase activity in the cardiomyocytes. On the contrary, inhibition of calcium overload by SF was markedly attenuated by addition of an NOS inhibitor, an NO scavenger, an soluble guanylate cyclase inhibitor, and a PKG inhibitor: N(G)-nitro-l-arginine methyl ester (L-NAME, 100 microM), 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazole-1-oxyl-3-oxide (c-PTIO, 1.0 microM), 1H-[1, 2, 4] oxadiazolo [4, 3-alpha] quinoxalin-1-one (ODQ, 20 microM) and KT5823 (0.2 microM), respectively. Our findings indicate that SF significantly attenuates anoxia/reoxygenation-induced Ca(2+) overload and improves cell survival in cultured cardiomyocytes through NO/cGMP/PKG signal pathway.
细胞内钙超载的发生是心肌缺血/再灌注或缺氧/复氧损伤中的一个重要病理生理因素。最近的研究表明，阿魏酸（SF）可刺激一氧化氮（NO）生成，并对缺血再灌注心脏发挥心脏保护作用。然而，SF的心脏保护作用是否与通过NO/环磷酸鸟苷（cGMP）/cGMP依赖性蛋白激酶（PKG）途径抑制Ca(2+)超载有关尚未确定。在本研究中，心肌细胞分别用100、200、400或800微摩尔/升的SF孵育3小时后，诱导缺氧/复氧损伤，并适当测量细胞内Ca(2+)浓度、一氧化氮合酶（NOS）活性、鸟苷酸环化酶活性、NO和cGMP生成。结果表明，SF处理可浓度依赖性地抑制缺氧/复氧诱导的钙超载。我们还证明，SF（100 - 800微摩尔/升）可通过增加心肌细胞中的NOS活性和鸟苷酸环化酶活性，浓度依赖性地增强NO和cGMP生成。相反，添加NOS抑制剂、NO清除剂、可溶性鸟苷酸环化酶抑制剂和PKG抑制剂：N(G)-硝基-L-精氨酸甲酯（L-NAME，100微摩尔/升）、2-(4-羧基苯基)-4,4,5,5-四甲基咪唑-1-氧基-3-氧化物（c-PTIO，1.0微摩尔/升）、1H-[1, 2, 4]恶二唑并[4, 3-α]喹喔啉-1-酮（ODQ，20微摩尔/升）和KT5823（0.2微摩尔/升）后，SF对钙超载的抑制作用明显减弱。我们的研究结果表明，SF可通过NO/cGMP/PKG信号通路显著减轻缺氧/复氧诱导的Ca(2+)超载，并提高培养心肌细胞的存活率。
