Kaempferide Improves Glycolipid Metabolism Disorder by Activating PPARγ in High-Fat-Diet-Fed Mice

Abstract Background: Kaempferide (Ka, 3,5,7-trihydroxy-4′-methoxyflavone), an active ingredient of Tagetes erecta L has been demonstrated to possess many pharmacological effects, including antioxidant, anti-inflammation, anticancer and antihypertension in previous study. However, there is no evidence of Ka on metabolic disorder in former studies. This study investigated the effects of Ka on glycolipid metabolism and explored the underlying mechanisms of action in vivo and vitro. Methods: High-fat diet (HFD) was used to induce the model of glycolipid metabolism disorder in mice.The hypolipidemic and hypoglycemic effect was detected by several indicators, like blood sample analysis blood glucose, serum insulin, HOMA index and intraperitoneal glucose tolerance tests (IPGTT). The signaling pathways of lipid metabolism (PPARγ/LXRα/ABCA1) and glucose metabolism (PPARγ/PI3K/AKT) were evaluated using Real-Time PCR and Western blot. The primary culture of hepatocytes was prepared to confirm the target of Ka by co-culturing with PPARγ agonist or inhibitor.Results: Administration of Ka at a dose of 10mg/kg for 16 weeks effectively attenuated obesity, hyperlipidemia, hyperglycemia and insulin resistance in HFD mice. Further studies revealed the hypolipidemic and hypoglycemic effects of Ka depended on the activation of PPARγ/LXRα/ABCA1 pathway and PPARγ/PI3K/AKT pathway, respectively. The primary hepatocyte test, co-cultured with PPARγ agonists or inhibitors, further confirmed the above signaling pathway and key protein. Conclusion: Ka played an important role in improving glycolipid metabolism disorder, which were causally associated with weight loss. The underlying mechanisms might are associated with the activation of PPARγ and its downstream signaling pathway. Our study helped to understand the pharmacological actions of Ka, and provides theoretical basis for Ka in the effective treatment of obesity, diabetes and other metabolic diseases.