Phytic acid actions on hepatic lipids and gut microbiota in rats fed a diet high in sucrose is influenced by dietary fat level.

Phytic acid (PA) or myoinositol intake was recently reported by our group to suppress hepatic lipogenic gene expression and modulate gut microbiota in rats fed a high-sucrose diet (HSC). The aim of this study was to investigate the effect of PA and dietary fat level on fatty liver and gut microbiota in rats fed an HSC diet. Male Sprague-Dawley rats were fed a high-fat (HF), HSC diet or a low-fat (LF), HSC diet with or without 1.02% sodium PA for 12 days. Hepatic lipid levels, hepatic enzyme activity, and expression of the enzymes and transcriptional factors related to lipid metabolism, cecal organic acids, and fecal microbiota were evaluated. PA intake depressed hepatic total lipid and triglyceride levels; reduced hepatic activity and expression of lipogenic enzymes; elevated fecal proportion of Lactobacillus spp; and increased cecal succinate level in rats fed the LF diet. The HF diet, when compared with the LF diet, depressed hepatic total lipid and triglyceride levels; reduced hepatic activity and expression of lipogenic enzymes; increased hepatic expression of carnitine palmitoyl-transferase 1a and cAMP-responsive element binding protein 3-like 3; and elevated fecal proportions of Lactobacillus spp and Bifidobacterium spp. In the HF diet groups, PA intake did not affect the factors associated with hepatic lipid metabolism and gut microbiota. In conclusion, dietary fat level could change the effect of PA on hepatic lipid metabolism and gut microbiota and, in turn, could alter the degree of nutritional importance of PA in rats fed an HSC diet.