Effects of ω-3 PUFA-Rich Oil Supplementation on Cardiovascular Morphology and Aortic Vascular Reactivity of Adult Male Rats Submitted to an Hypercholesterolemic Diet

SIMPLE SUMMARY: Currently, processed and ultraprocessed foods represent a significant component of the diet of modern societies, increasing the risk of developing obesity, diabetes and atherosclerosis. Therefore, replacing saturated fats with mono- and polyunsaturated fats, such as omega-3 polyunsaturated fatty acids (ω-3 PUFAs), has been considered as a dietary strategy to reduce clinical events related to atherosclerosis. In the present study, the effects of 56-day ω-3 PUFA-rich oil supplementation on liver function, lipid profile, and oxidative stress in hypercholesterolemic rats were investigated, as well as its impact on cardiovascular health. Interestingly, we observed a positive effect in reducing hepatic markers, preserving cardiovascular morphology, and increasing vasodilator responsiveness. These findings contribute to the generation of consistent recommendations for the therapeutic use of ω-3 PUFAs in the treatment of atherosclerosis, leading to a consequent reduction in related morbidity and mortality. ABSTRACT: Atherosclerosis is a cardiovascular disease associated with abnormalities of vascular functions. The consumption of mono- and polyunsaturated fatty acids can be considered a strategy to reduce clinical events related to atherosclerosis. In the present study, we investigated the effects of supplementation with 310 mg of ω-3 PUFAs (2:1 eicosapentaenoic/docosahexaenoic acids) for 56 days on rats with hypercholesterolemia induced by a diet containing cholesterol (0.1%), cholic acid (0.5%), and egg yolk. Serum biochemical parameters were determined by the enzymatic colorimetric method. Assessment of vascular effects was performed by analysis of histological sections of the heart and aortic arch stained with hematoxylin and eosin and vascular reactivity of the aorta artery. We observed that treatment with ω-3 PUFAs did not promote alterations in lipid profile. On the other hand, we documented a favorable reduction in liver biomarkers, as well as contributions to the preservation of heart and aortic arch morphologies. Interestingly, the vascular reactivity of rat thoracic aortic preparations was improved after treatment with ω-3 PUFAs, with a decrease in hyperreactivity to phenylephrine and increased vasorelaxation promoted by acetylcholine. Our findings suggest that the supplementation of hypercholesterolemic rats with ω-3 PUFAs promoted improvement in liver and vascular endothelial function as well as preserving heart and aortic tissue, reinforcing the early health benefits of ω-3 PUFAs in the development of atherosclerotic plaque and further related events.