Wednesday, May 13, 2015

Betaine alleviates hepatic lipid accumulation via enhancing hepatic lipid export and fatty acid oxidation in rats fed with a high-fat diet

To assess the effects of betaine on hepatic lipid accumulation and investigate the underlying mechanism, thirty-two male Sprague-Dawley rats weighing 100 (sd 2.50) g were divided into four groups, and started on one of four treatments: basal diet, basal diet with betaine administration, high-fat diet and high-fat diet with betaine administration. The results showed that no significant difference of body weight was found among experimental groups. Compared with high-fat diet-fed rats, a betaine supplementation decreased (P< 0.05) hepatic TAG accumulation induced by high-fat diet, which was also supported by hepatic histology results. Additionally, hepatic betaine-homocysteine methyltransferase activity as well as its mRNA abundance and lecithin level were found increased (P< 0.05) by betaine supplementation in both basal diet-fed rats and high-fat diet-fed rats. Betaine administration in high-fat diet-fed rats exhibited a higher (P< 0.05) activity of hepatic carnitine palmitoyltransferase 1 (CPT1) compared with high-fat diet-fed rats. High-fat diet inhibited (P< 0.05) the gene expression of hepatic PPARalpha and CPT1. However, betaine administration in high-fat diet-fed rats elevated (P< 0.05) the gene expression of PPARalpha and CPT1. Moreover, concentration, gene and protein expressions of hepatic fibroblast growth factor 21 (FGF21) were increased (P< 0.05) in response to betaine administration in high-fat diet group; meanwhile the gene expression of hepatic AMP-activated protein kinase was increased (P< 0.05) as well. The results suggest that betaine administration enhanced hepatic lipid export and fatty acid oxidation in high-fat diet-fed rats, thus effectively alleviating fat accumulation in the liver.

Xu, L., et al., Betaine alleviates hepatic lipid accumulation via enhancing hepatic lipid export and fatty acid oxidation in rats fed with a high-fat diet. Br J Nutr, 2015: p. 1-9