Intake of stigmasterol and β-sitosterol alters lipid metabolism and alleviates NAFLD in mice fed a high-fat western-style diet. - GreenMedInfo Summary

OBJECTIVE: To investigate and compare the effects of two common dietary phytosterols, stigmasterol andβ-sitosterol, in altering lipid metabolism and attenuating nonalcoholic fatty liver disease (NAFLD).

METHODS: Stigmasterol andβ-sitosterol were administered to mice at 0.4% in a high-fat western-style diet (HFWD) for 17 weeks.

RESULTS: Stigmasterol andβ-sitosterol significantly ameliorated HFWD-induced fatty liver and metabolic abnormalities, including elevated levels of hepatic total lipids, triacylglycerols, cholesterol and liver histopathology. Both phytosterols decreased the levels of intestinal bile acids, accompanied by markedly increasedfecal lipid levels. In addition, they altered the expression of genes involved in lipid metabolism. β-Sitosterol was less effective in affecting most of these parameters. Lipidomic analysis of liver and serum samples showed that stigmasterol prevented the HFWD-induced elevation of some di- and triacylglycerol species and lowering of some phospholipid species. Stigmasterol also decreased serum levels of ceramides.

CONCLUSION: Stigmasterol andβ-sitosterol, at a dose corresponding to that suggested for humans by the FDA for lowering cholesterol levels, are shown to alleviate HFWD-induced NAFLD. Stigmasterol was more effective than β-sitosterol, possibly because of its suppression of hepatic lipogenic gene expression and modulation of circulating ceramide levels.