Is the protection against ischemia induced by red wine linked to its antioxidant capacity?

To establish whether the total antioxidant capacity of nonalcoholic extracts of three Argentine red wines (RWE) is correlated with their protection against ischemia-reperfusion injury.

The antioxidant properties of three RWE were determined using different free radical-generating systems. To examine the effects of these RWE during a 20 min global ischemic period followed by 30 min of reperfusion, isolated rat hearts received 50 mug/mL of RWE 1 (cabernet-sauvignon), RWE 2 (malbec) or RWE 3 (a commercial mixture of cabernet-sauvignon, malbec and merlot) 10 min before and after ischemia. Left ventricular developed pressure (LVDP), maximal velocity of rise of left ventricular pressure (+dP/dt(max)) and left ventricular end-diastolic pressure (LVEDP) were used to assess contractility and diastolic function.

All RWE inhibited lipid peroxidation induced by the Cl(4)C/NADPH system in a similar proportion (42+/-4%, 47+/-9% and 43+/-14% for RWE 1, RWE 2 and RWE 3, respectively). The scavenging activity of superoxide anion and 2,2-diphenyl-1-picryl-hydrazyl radical was about the same with the three RWE. In hearts without RWE treatment, LVDP and +dP/dt(max) were 61+/-4% and 62+/-5%, respectively, at the end of the reperfusion period. Infusion of RWE 1 and RWE 2 significantly improved postischemic recovery (LVDP and +dP/dt(max) were 102+/-4% and 101+/-4% for RWE 1 and 92+/-5% and 91+/-5% for RWE 2, respectively) and attenuated the increase of LVEDP. RWE 3 did not improve either systolic or diastolic dysfunction.

These data show that although the three non-alcoholic RWE exhibit a similar total antioxidant capacity, only two of them protect the heart against myocardial stunning, suggesting that the protective effect is not primarily linked to the anti-oxidant properties of the extracts.