Sex‐dependent effect of prenatal and early postnatal red palm oil supplementation on cardiac ischemic tolerance of adult rats

Abstract

Female Wistar rats were fed a standard diet supplemented with 0.25 ml/day of red palm oil (RPO) for 4 wks before mating, during pregnancy and until weaning at the offspring age of 4 wks; the second group was fed a control diet. Body mass of supplemented male and female offspring was higher compared to their respective controls and the faster growth continued after the cessation of RPO supplementation till adulthood. At the age of 14 wks, myocardial antioxidant enzyme levels were assessed and separate groups of offspring were subjected to 20 min of coronary artery occlusion and 3 h of reperfusion. RPO supplementation resulted in a more pronounced down‐regulation of superoxide dismutase 2 and glutathione peroxidase 1 in females than in males. The incidence and severity of ischemic ventricular arrhythmias was much lower in control females than in males. RPO markedly reduced the total number of arrhythmias and arrhythmia score in males to the same level as observed in control females, mainly due to a suppression of ventricular tachycardia. In contrast, RPO had no additive antiarrhythmic effect in females. Myocardial infarct size did not significantly differ between males and females and was not affected by RPO. The results indicate that RPO supplementation during early ontogeny may protect the adult rat heart against malignant ischemic arrhythmias in a sex‐dependent manner.Supported by URF, CPUT, SA and Carotino Malaysia.