Regular alcohol consumption mimics cardiac preconditioning by protecting against ischemia–reperfusion injury

Abstract

Epidemiologic studies indicate that longterm alcohol consumption decreases the incidence of coronary disease and may improve outcome after myocardial infarction. Attenuation of ischemia-reperfusion injury after myocardial infarction improves survival. This study investigates the possibility that alcohol consumption can improve survival after myocardial infarction by reducing ischemia-reperfusion injury. Hearts were isolated from guinea pigs after drinking ethanol for 3-12 weeks and subjected to global ischemia and reperfusion. Hearts from animals drinking ethanol showed improved functional recovery and decreased myocyte damage when compared with controls. Adenosine A 1 receptor blockade abolished the protection provided by ethanol consumption. These findings indicate that long-term alcohol consumption reduces myocardial ischemia-reperfusion injury and that adenosine A 1 receptors are required for this protective effect of ethanol. This cardioprotective effect of long-term alcohol consumption mimics preconditioning and may, in part, account for the beneficial effect of moderate drinking on cardiac health.

Activation of ɛ protein kinase C correlates with a cardioprotective effect of regular ethanol consumption

“…Male Hartley guinea pigs (275-300 g; n ϭ 9 ethanol; n ϭ 9 control) were given 10% (a dose more consistent with moderate consumption) or 0% ethanol and solid food ad libitum (Lab Diet: PMI Feeds, St. Louis) for 8 wk as described previously (14). Isolated hearts were perfused for 10 min with Krebs-Henseleit perfusate (pH 7.4, 37°C) bubbled with 95%O 2 /5%CO 2 .…”

“…The increasing use of emergent reperfusion therapies during acute MI, including thrombolysis and coronary angioplasty, provides impetus for finding therapies to reduce ischemia-reperfusion injury. We recently found that regular ethanol consumption induces long-term protection against ischemia-reperfusion injury in guinea pig hearts (14). We showed that this cardioprotective effect of ethanol requires adenosine A 1 receptor activation at the time of ischemia (14), like experimental ischemic preconditioning (15)(16)(17)(18)(19).…”

“…We recently found that regular ethanol consumption induces long-term protection against ischemia-reperfusion injury in guinea pig hearts (14). We showed that this cardioprotective effect of ethanol requires adenosine A 1 receptor activation at the time of ischemia (14), like experimental ischemic preconditioning (15)(16)(17)(18)(19). Ischemic preconditioning occurs when brief periods of ischemia and reperfusion protect hearts against injury from subsequent prolonged ischemia-reperfusion.…”

“…Future studies will further elucidate the role of PKC in this long-term cardioprotective effect of regular ethanol consumption and its relationship to adenosine A 1 receptor activation (14).…”

Alcohol and the heart: To abstain or not to abstain?

“…[28,118] Ischemic preconditioning (IPC) is the most potent form of endogenous myocardial protection against irreversible ischemia-reperfusion injury. In an animal models, longterm alcohol consumption reduced myocardial ischemia-reperfusion injury possibly through repeated myocyte adenosine receptor activation, [119] and sustained translocation of epsilon protein kinase C (εPKC). [120] In situ studies in rabbit showed, ethanol exposure followed by washout or sufficient time to metabolize the alcohol prior to ischemia, induces preconditioning-like myocardial protection.…”