Drynaria rhizome water extract alleviates high-fat diet-induced obesity in mice

Drynaria rhizome is a herbal medicine used for strengthening bones and treating bone diseases in East Asia. Although obesity is considered to benefit bone formation, it has been revealed that visceral fat accumulation can promote osteoporosis. Given the complex relationship between bone metabolism and obesity, bone-strengthening medicines should be evaluated while considering the effects of obesity. The present study investigated the effects of Drynaria rhizome extract (DRE) on high-fat diet (HFD)-induced obese mice. DRE was supplemented with the HFD. Body weight, food intake, the expression levels of lipogenesis transcription factors, including sterol regulatory element binding protein (SREBP)-1, peroxisome proliferator-activated receptor (PPAR)-gamma and adenosine monophosphate-activated protein kinase (AMPK)-alpha, and AMPK activation were evaluated. Mice fed DRE and a HFD exhibited reduced body weight without differences in food intake compared with those in the HFD group. Furthermore, DRE; upregulated AMPK-alpha of epididymal one; down-regulated SREBP-1 and PPAR-gamma, as determined using western blotting and quantitative polymerase chain reaction, respectively. Decreased lipid accumulation were observed in both fat pad and liver of HFD-fed mice, which were suppressed by DRE treatment. These results demonstrated the potential of DRE as a dietary natural product for strengthening bones and managing obesity.