In this study, we investigated the cardioprotective mechanisms of action of DT-010, a novel danshensutetramethylpyrazine conjugate. DT-010 significantly preserved cell viability and suppressed cell apoptosis in H9c2 cells injured by tert-butylhydroperoxide (t-BHP), iodoacetic acid (IAA) and hypoxia-reoxygenation. In addition, DT-010 pre-treatment reduced the intracellular level of free radicals including superoxide anion (·O 2 ), hydroxyl radical (·OH) and peroxynitrite anion (ONOO ) after t-BHP exposure. Moreover, DT-010 up-regulated the protein expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) and nuclear factor-E2-related factor 2 (Nrf2) as well as mitochondrial transcription factor A (Tfam) and heme oxygenase-1 (HO-1) in H9c2 cells. DT-010 also triggered Nrf2 nuclear translocation. In a rat myocardial ischemia-reperfusion model, DT-010 significantly alleviated myocardial infarction. The results indicated that DT-010 may be a promising candidate for the treatment of cardiovascular diseases, particularly myocardial ischemia and reperfusion injury.Key words Danshensu derivative; oxidative stress; apoptosis; myocardial ischemia reperfusion injury; peroxisome proliferator-activated receptor gamma coactivator 1 alpha/nuclear factor-E2-related factor 2/heme oxygenase-1 (PGC-1α/Nrf2/HO-1) pathway Myocardial ischemia is a primary cause of sudden death worldwide. Myocardial ischemia results from a decreased blood flow to the heart, preventing the heart from receiving adequate supply of energy. The reduced blood flow is usually caused by a partial or complete blockade of the arteries. Traditional treatments focus on restoring blood supply, such as by pass-graft surgery, dilation of coronary artery and coronary thrombolysis, and etc. 1) Although restoration of blood flow to the ischemic heart tissues is important, it is not adequate because myocardial ischemic damage is progressively developed following reperfusion due to an over-production of a large number of biospecies. 2,3) Compelling evidence demonstrated that free radicals generated during ischemia and reperfusion play pivotal roles in myocardial apoptosis. Free radical scavengers can effectively inhibit myocardial apoptosis. The previous studies have demonstrated that agents that combine anti-thrombolytic and anti-oxidative activities showed promising therapeutic efficacy in the treatment of myocardial ischemia. 4,5) In China, many traditional herbs have been used to prevent and treat myocardial ischemia. Among them are Salvia miltiorrhiza (Danshen) and Ligusticum wallichii (Chuanxiong). As the major active ingredients, (3-(3,4-dihydroxyphenyl) lactic acid) (Danshensu, DSS, Fig. 1) isolated from Danshen and tetramethylpyrazine (TMP, Fig. 1) isolated from Chuanxiong have a variety of biological activities. They lyse blood clot, dilate coronary arteries, inhibit platelet aggregation, scavenge free radicals, improve microcirculation and have anti-inflammatory properties. 6,7) Both of them are widely used in clinic for treatm...
