Modulation of cardiac function by the chronic supplementation with ω-3 polyunsaturated fatty acids

ZAVALA MR,; VÉLEZ RUEDA O; LONGARZO L; MATÉ SM; ALMADA MJ; VILLA-ABRILLE MC.

Rosario

Congreso; Reunión anual SAFIS; 2019

Modulation of cardiac function by the chronic supplementation with n-3 polyunsaturated fatty acids Maite R. Zavala, Lucrecia Longarzo, María J Almada, Omar Vélez Rueda Sabina M. Maté, María C. Villa-Abrille.Several studies have shown that supplementation with polyunsaturated n-3 fatty acids (PUFAs) leads to modifications on the cardiac physiology. Dietary fatty acids have been found to affect lipid raft composition, affecting cell function. The Na+/H+ exchanger (NHE1), an integral membrane protein, is involved in the maintenance of the intracellular pH (pHi). Its activity is regulated by allosteric site sensitivity for H+, phosphorylation and by the union of ATP, lipids, growth factors in its cytoplasmic tail. The objective of the present work was evaluate the effect of two major PUFAs, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on the modulation of NHE1 activity and cardiac function in normo (Wistar, W) and spontaneously hypertensive rats (SHR). The animals received orally 200 mg/kg body mass/day of EPA and DHA. After 3 months of treatment we measured: systolic blood pressure (SP), echocardiographic parameters (left ventricular mass index LVMI, fractional shortening FS%, and ejection fraction EF %). The rats were sacrificed and obtain ventricular cardiomyocytes for measured the NHE1 activity. The SHR rats showed a significant increase in the SP compared with the Wistar rats. However, although the treatment with PUFAs did not affect the SP in SHR, we observed a modestly, but not significant, reduction in the cardiac hypertrophic index (LVMI). The activity of NHE1 measured as the velocity of pHi recovery (dpHi/dt) after intracellular acidification, was significantly higher in SHR compared with the Wistar rats. The dietary PUFAs did not affect the activity of the exchanger in Wistar rats. On the other hand in SHR, we observed a modest, although not significant, decrease in the NHE1 activity, showing a velocity recovery similar to Wistar rats.Together, these preliminary results allow us to suggest that the PUFAs supplement in hypertensive rats could improve the cardiac function through the decrease in the NHE1 activity and the cardiac hypertrophy, despite similar values of SP (afterload).