Magnesium lithospermate B improves metabolic changes in high-fat diet-fed rats with metabolic syndrome

Danshen, the roots of Salvia miltiorrhiza, is a natural food and traditional Chinese herb possessing antidiabetic and antilipidaemic activities. In the present study, the beneficial effects and possible mechanisms of Magnesium lithospermate B (MLB), the major soluble constituent in Danshen, were investigated in a rodent model of metabolic syndrome induced by a high-fat diet (HFD). Daily supplementation of MLB improved obesity, hyperlipidaemia, hyperglycaemia, glucose intolerance, insulin resistance, and hepatic steatosis caused by HFD. Mechanistic studies showed that MLB caused a down-regulation of fatty acid transporter CD36 and lipogenic transcription factor sterol regulatory element-binding transcription factor 1c (SREBP1c) expression and an up-regulation of lipolytic transcription factor peroxisome proliferator-activated receptor-α (PPARα) expression and post-receptor insulin signalling. In addition, MLB supplementation attenuated proinflammatory cytokine and adipokine expression. These results suggest that MLB may be an active ingredient contributing to the beneficial effects of Danshen on insulin resistance as well as on metabolic syndrome.