Altered heart and kidney phospholipid fatty acid composition are associated with cardiac hypertrophy in hypertensive rats

Abstract

Objective: We examined the association of cardiac hypertrophy or fibrosis with the phospholipid fatty acid (FA) composition of heart and kidney in hypertensive rats. Design and methods: Eight-week-old spontaneously hypertensive rats (SHRs) (n = 8) and Wistar Kyoto rats (WKYs, n = 8) as a normotensive control, were fed ad libitum for 6 weeks with regular AIN-76 diet. Phospholipid FA compositions in the left ventricle and kidney were measured and histological analyses were performed. Results: Compared with VVKYs, SHRs had lower proportions of gamma-linolenic acid, alpha-linolenic acid, eicosadienoic acid, eicosatrienoic acid, dihomo-gamma-linoleic acid, docosadienoic acid and nervonic acid in heart, and stearic acid (SA), gamma-linolenic acid, and eicosapentaenoic acid (EPA) in kidney. After adjusting for food intake, SHRs still maintained higher proportions of SA, and total saturated FAs in the heart and a lower proportion of eicosapentaenoic acid in the kidney. Additionally, compared with WKYs, SHRs showed larger cardiomyocyte diameters in the left ventricles, indicating cardiac hypertrophy and interstitial fibrosis. Cardiomyocyte diameters also positively correlated with cardiac SA (r = 0.550, p < 0.05) and negatively with kidney EPA (r = -0.575, p < 0.05). Conclusion: Tissue FA compositions were associated with cardiac hypertrophy in a hypertensive setting, implicating the pathogenic role of tissue FAs in hypertension and related complications. (C) 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.