The cardiac effects of prolonged vitamin B12 and folate deficiency in rats.

In the recent past, hyperhomocysteinemia (HHCY) has been linked to chronic heart failure. Folate and vitamin B12 deficiencies are the common causes of HHCY. The impact of these vitamins on cardiac function and morphology has scarcely been investigated. The aim of this study was to conduct an analysis of the cardiac effect of folate and vitamin B12 deficiency in vivo. Two groups of rats, a control (Co, n = 10) and a vitamin-deficient group (VitDef, n = 10), were fed for 12 weeks with a folate and vitamin B12-free diet or an equicaloric control diet. Plasma and tissue concentrations of HCY, S-adenosyl-homocysteine (SAH), S-adenosyl-methionine (SAM), and brain natriuretic peptide (BNP) were measured. Moreover, echocardiographic and histomorphometric analyses were performed. VitDef animals developed a significant HHCY (Co vs VitDef: 6.8 +/- 2.7 vs 61.1 +/- 12.8 micromol/l, P < 0.001). Fractional shortening, left ventricular dimension at end-diastole and end-systole, posterior wall thickness, perivascular collagen, mast cell number, and BNP tissue levels were comparable in VitDef and Co animals. Interstitial collagen (Co vs VitDef: 6.8 +/- 3.0 vs 4.5 +/- 2.1%, P < 0.05), plasma BNP (Co vs VitDef: 180 +/- 80 vs 70 +/- 60 ng/l, P < 0.05), and tissue HCY (Co vs VitDef: 0.13 +/- 0.07 vs 0.07 +/- 0.04 micromol/g protein, P < 0.05) were lower in VitDef animals. Folate and vitamin B12 deficiency do not affect cardiac function and morphology.