Oilseeds ameliorate metabolic parameters in male mice, while contained lignans inhibit 3T3-L1 adipocyte differentiation in vitro.

PURPOSE AND BACKGROUND: The focus was directed to the study of two of the most lignan-rich food sources: sesame and flaxseeds. Recent epidemiological and experimental evidences suggesting that these foods may improve metabolic functions underlying metabolic syndrome (MetS). METHODS: To characterize the effect of these oilseeds on metabolic functions, we conducted an experimental study aimed at preventing adiposity and metabolic imbalance in a mouse model of high-fat diet (HFD)-induced MetS. Statistical analysis was performed by two-way analysis of variance test followed by post hoc Bonferroni analysis. RESULTS: We studied the effect of the oilseeds sesame and flaxseed on metabolic parameters in mice on a HFD. When the HFD was integrated with 20% of sesame or flaxseed flours, the mice showed a decrease in body fat, already at day 15, from time 0. The size of the adipocytes was smaller in epididymal fat, liver steatosis was inhibited, and insulin sensitivity was higher in mice on the supplemented diets. The supplemented diets also resulted in a significant increase in the serum levels of the lignan metabolites enterodiol and enterolactone compared with the controls. The expression of genes associated with the inflammatory response, glucose metabolism, adipose metabolism and nuclear receptor were altered by the oilseed-supplemented diets. Some of the most abundant lignans in these oilseeds were studied in 3T3-L1 preadipocyte cells and were effective in inhibiting adipocyte differentiation at the minimal dose of 1 nM. CONCLUSIONS: The consumption of sesame and flaxseed may be beneficial to decrease metabolic parameters that are generally altered in MetS.