6'-O-acetyl mangiferin from Iris rossii Baker inhibits lipid accumulation partly via AMPK activation in adipogenesis.

Effective control of white adipose tissue accumulation would provide a therapeutic strategy for obesity, which poses a growing global problem. The plant chemical mangiferin stimulates adenosine monophosphate-activated protein kinase (AMPK), which inhibits adipogenesis and has therefore been considered a therapeutic target for obesity and related diseases. We previously reported the anti-inflammatory properties of 6'-O-acetyl mangiferin (OAM). In this study, we evaluated the potential of OAM as an AMPK activator in vitro in 3T3-L1 preadipocytes. OAM inhibited adipogenesis as indicated by lower intracellular lipid and triglyceride accumulation as well as reduced adipogenic gene and protein expression upon treatment. OAM-treated 3T3-L1 cells excreted more glycerol, indicating increased lipolysis, which was supported by increased expression of lipolysis-related genes, including adipose triglyceride lipase and hormone-sensitive lipase. We determined that OAM upregulates lipolysis via phosphorylation-dependent activation of AMPK. Further, OAM upregulated the β-oxidation pathway as indicated by enhanced expression of phosphorylated acetyl-CoA-carboxylase and long-chain acyl-CoA synthetase 1. In conclusion, OAM markedly decreased intracellular lipid accumulation by enhancing lipolysis via AMPK activation and by upregulating β-oxidation. Thus, OAM has potential as a drug for the prevention and/or improvement of obesity and related diseases and deserves further study.