Extra Virgin Olive Oil Protected Against Hyperthyroidism-Induced Cardiac Dysfunction Via Reduced Angiotensin-II Receptor Expression in Adult Male Rats

Background: Hyperthyroidism-induced cardiac dysfunction is a common disorder that was linked to the interplay between oxidative stress and activated renin-angiotensin system. Studies related the consumption of extra virgin olive oil (EVOO) to the lower risk of cardiovascular diseases.Aim of the Work: So, this study aimed to evaluate the cardioprotective effects of extra virgin olive oil (EVOO) in experimentally induced hyperthyroidism with possible involvement of angiotensin-II receptor 1 (Ang-II-R1) and the antioxidant hemeoxygenase-1 (HO-1) enzyme.Methods: Thirty adults male Wistar rats, allocated into 3 groups, control, Hyperthyroid group; received intraperitoneal injection of 100μg/kg L-thyroxine daily for 4 consecutive weeks, EVOO-treated hyperthyroid group; received L-thyroxine as in group II, then by the beginning of the third week, 1ml/100g EVOO by gavage daily for 2 weeks.Results: EVOO-treated hyperthyroid rats showed significant body weight reduction with PR interval restoration near the control level. EVOO resulted in significant reduction in Ang-II-R mean % area and optical density with consequent reduction in the cardiac HO-1. This reduction was correlated with the improvement in basal cardiac inotropic function and cardiac inotropic response following isoproterenol infusion together with partial reversal of the hyperthyroid induced histological changes.Conclusion: Prophylactic use of EVOO in hyperthyroidism could minimize the cardiac dysfunction and structural alterations by reducing Ang-II-R1 overexpression and mitigating oxidative stress.