Anti-obesity Effect of Raphani Semen Extract in Mice Fed a High-fat Diet

Abstract

Raphani Semen, a dried seed of radish, is used as a traditional Asian medicine to treat hypertension and digestive disorders. Sulforaphene (SFEN) is a main bioactive component in Raphani Semen, which has been shown to exhibit anti-adipogenesis effect in vitro. Here SFEN-enriched Raphani Semen extract (RSE) was prepared and effects of RSE on obesity, fatty liver and glucose intolerance were examined in mice fed a high-fat diet (HFD). Male C57BL/6J mice were fed a HFD for 16 weeks with or without RSE or black bean peptide (BBP) (n=9/group). Body weights of HFD-fed mice increased as compared to standard diet (SD), whereas both RSE and BBP suppressed HFD-induced increase in body weight after 16 weeks. In addition, RSE-supplementation inhibited HFD-induced fatty liver in mice by reducing hepatic triglyceride (TG) accumulation. To further investigate the underlying mechanisms involved in the reduction of body weight and liver TG in RES-supplemented mice, the expression levels of fatty acid metabolism related genes in epididymal white adipose tissue (eWAT) and liver were evaluated. HFD significantly decreased the expression levels of pgc1 as compared to SD, but RSE increased their levels in eWAT. HFD also reduced the expression levels of cpt-1a and acox1 in liver, whereas RSE significantly increased the levels of both genes. These data indicate that RSE suppressed HFD-induced obesity and fatty liver via upregulation of fatty acid metabolism. Moreover, RSE supplementation dramatically improved glucose tolerance as compared to HFD-fed mice. These results suggest that RSE can be used to prevent obesity and metabolic syndromes.