Chronic dietary intake of quercetin alleviates hepatic fat accumulation associated with consumption of a Western-style diet in C57/BL6J mice

Scope: To determine the effect of consumption of a quercetin-rich diet on obesity and dysregulated hepatic gene expression. Methods and results: C56BL/6J mice were fed for 20wk on AIN93G (control) or a Western diet high in fat, cholesterol and sucrose, both with or without 0.05% quercetin. Triglyceride levels in plasma, thiobarbituric acid-reactive substances (oxidative stress marker) and glutathione levels and peroxisome proliferator-activated receptor alpha expression in livers of mice fed with the Western diet were all improved after 8wk feeding with quercetin. After 20 wk, further reductions of visceral and liver fat accumulation and improved hyperglycemia, hyperinsulinemia, dyslipidemia and plasma adiponectin and TNF alpha levels in these mice fed with quercetin were observed. The expression of hepatic genes related to steatosis, such as peroxisome proliferator-activated receptor gamma and sterol regulatory element-binding protein-1c was also normalized by quercetin. In mice fed with the control diet, quercetin did not affect body weight but reduces the plasma TNF alpha and hepatic thiobarbituric acid-reactive substance levels. Conclusion: In mice fed with a Western diet, chronic dietary intake of quercetin reduces liver fat accumulation and improves systemic parameters related to metabolic syndrome, probably mainly through decreasing oxidative stress and reducing PPAR alpha expression, and the subsequent reduced expression in the liver of genes related to steatosis.