RESUMEN
Moderate ethanol drinking (ED) and n-3 fatty acids have both been associated with low cardiac mortality. However, there are few data evaluating the interactions of ED with n-3. We recently reported that moderate ED results in increased n-3 in cardiac patients. The main aim of the present study was, through a well-controlled experimental model, to confirm that chronic ED actually results in increased n-3. Secondary aims were to examine the effects of chronic ED on cardiac mitochondria, cardiac function and experimental myocardial infarction. We studied the fatty acid profiles of plasma, cell membranes and cardiac mitochondria phospholipids in a rat model of chronic ED. In plasma and cell membranes, ED actually resulted in higher n-3 (P = 0.005). In mitochondria phospholipids of ED rats, n-3 were also increased (P < 0.05) but quite modestly. Cardiac mitochondrial function and left ventricular function were not significantly different in ED and control rats, while infarct size after 30 min ischaemia and reperfusion was smaller (P < 0.0001) in ED rats. This is the first animal study confirming interaction of alcohol drinking with n-3. We found no harmful effect of chronic ED on the heart in that model but a significant cardioprotection. Further studies are warranted to investigate the mechanisms by which moderate ED alters the metabolism of n-3 and whether n-3 are the mediators of the ED-induced cardioprotection.
Asunto(s)
Consumo de Bebidas Alcohólicas/sangre , Ácidos Grasos Omega-3/sangre , Animales , Membrana Celular/metabolismo , Modelos Animales de Enfermedad , Etanol/administración & dosificación , Etanol/farmacología , Ácidos Grasos/sangre , Lípidos/sangre , Masculino , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/fisiología , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/prevención & control , Fosfolípidos/metabolismo , Ratas , Ratas Wistar , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
BACKGROUND AND AIM: There are only little data about the effects of lipid-lowering drugs (LLDs) on the metabolism of essential n-6 and n-3 fatty acids in patients with established coronary heart disease (CHD). METHODS AND RESULTS: Male patients with CHD and high cholesterol levels (>6.2 mmol/L) were randomized (double-blind protocol) to receive either simvastatin 20mg (S) or fenofibrate 200mg daily (F) for 3 months. Dietary habits and plasma fatty acids were not different in the two groups at baseline. After treatment, there were significant changes in both the groups for the main n-6 fatty acids, with an increase in arachidonate (from 6.5+/-1.7% of total fatty acids to 7.5+/-2.1, p<0.001 in S and from 6.2+/-1.4 to 6.8+/-1.4, p<0.005 in F) and a decrease in linoleate (from 26.9+/-3.9 to 24.2+/-3.6, p<0.001, and from 27.8+/-3.4 to 26.1+/-4.2, p<0.05, in S and F, respectively). In addition, there was a decrease in two major n-3 fatty acids (alpha-linolenate and docosahexanoate, both p<0.05), but only in F. CONCLUSIONS: For the first time in a double-blind randomized study in CHD patients, we report that LLDs significantly alter the metabolism of essential fatty acids that are critically important for the pathogenesis and prevention of CHD. Further studies are urgently needed to examine the effects of higher dosages of statins (as currently proposed to reduce more cholesterol) on these essential fatty acids in the clinical setting and the crucial questions of whether specific dietary intervention (combining low intake of n-6 fatty acids and high intake of n-3 fatty acids) may improve the effectiveness of these drugs.