Coumarin-derived imino sulfonate 5h ameliorates cardiac injury induced
by myocardial infarction via activating Sirt1/Nrf2 signaling pathway
Abstract
Background and Purpose: Myocardial infarction (MI) is an irreversible
damage caused by ischemia and hypoxia in coronary arteries accompanied
with elevated levels of catecholamine, leading to the accumulation of
free radicals. Our previous study discovered coumarin-derived imino
sulfonates as a novel class of potential cardioprotective agents
possessing strong anti-oxidative effect in cardimyocytes. Therefore, the
identification of the compound with the highest cardioprotective
activity, 5h, and the mechanism involved was necessary. Experimental
Approach: As a kind of catecholamine, isoproterenol induces MI injury
mimicking symptoms of MI patients in clinic. Cardiac function, nfarct
area, histopathological changes were evaluated. The potential mechanism
underlying such action of compound 5h was explored via transfection with
adenovirus to downregulate Sirt1 in vitro, and by administration of
Ex527, the specific inhibitor for Sirt1, in vivo. Key Results: Compound
5h exhibited strong cardioprotective actions in vivo and in vitro via
improving cell survival, cardiac function and decreasing the cellular
oxidative stress and cardiac infarct size against MI. Furthermore,
compound 5h significantly enhanced cardiac expression of Sirt1,
subsequently activating the Nrf2/NQO1 signaling pathway. However,
adenovirus induced Sirt1 downregulation or Sirt1 specific inhibitor
largely blocked such beneficial effects of 5h in vitro and in vivo,
respectively. Conclusions and Implications: Our results demonstrated,
for the first time, that the cardioprotective action of 5h against MI
was mediated by reducing oxidative stress and apoptosis through the
Sirt1/Nrf2 signaling pathway. Our findings proposed novel insights in
the development and evaluation of coumarin-derived imino sulfonate
compounds as epigenetics-targeted drug therapy for MI.