Ventricular remodeling induced by tissue vitamin A deficiency in rats.

Abstract

BACKGROUND/AIMS: Experimental studies suggest that vitamin A plays a role in regulating cardiac structure and function. We tested the hypothesis that cardiac vitamin A deficiency is associated with adverse myocardial remodeling in young adult rats. METHODS: Two groups of young female rats, control (C - n = 29) and tissue vitamin A deficient (RVA - n = 31), were subjected to transthoracic echocardiography exam, isolated rat heart study and biochemical study. RESULTS: The RVA rats showed a reduced total vitamin A concentration in both the liver and heart [vitamin A in heart, micromol/kg (C = 0.95 +/- 0.44 and RVA = 0.24 +/- 0.16, p = 0.01)] with the same serum retinol levels (C = 0.73 +/- 0.29 micromol/L e RVA = 0.62 +/- 0.17 micromol/L, p = 0.34). The RVA rats showed higher left ventricular diameters and reduced systolic function. The RVA rats also demonstrated increased lipid hydroperoxide/total antioxidant capacity ratio and cardiac levels of IFN-gamma and TNF-alpha but not of metalloproteinase (MMP)-2 and -9 activity. On the other hand, the RVA rats had decreased levels of beta-hydroxyacylcoenzyme A dehydrogenase and lactate dehydrogenase. CONCLUSIONS: Tissue vitamin A deficiency stimulated cardiac remodeling and ventricular dysfunction. Additionally, the data support the involvement of oxidative stress, energy metabolism, and cytokine production in this remodeling process.