Ginsenoside-Rb1 promotes adipogenesis through regulation of PPARγ and microRNA-27b.
Ginsenoside-Rb1 (Rb1), one of the bioactive components in ginseng extract, is recently reported to be able to promote adipogenesis and peroxisome proliferator-activated receptor gamma (PPARγ) expression. Meanwhile, microRNA-27b (miR-27b) is also identified to regulate adipogenesis by targeting PPARγ2. In the present study, we attempted to link up the Rb1-promoted adipogenesis with PPARγ binding and miR-27b regulation. First, we demonstrated that GW9662, an antagonist of PPARγ, could block Rb1-induced 3T3-L1 differentiation with little toxicity towards cell proliferation. Then, expression levels for both of miR-27b and its primary transcript, pri-mir-27b, were found to decrease upon Rb1 treatment. Again, GW9662 could attenuate the inhibitory effect of Rb1 on both miR-27 and pri-mir-27b expression. Since Rb1 was demonstrated to have binding activity towards PPARγ, we thus speculate that Rb1 may act though PPARγ to downregulate mir-27b gene transcription and mature miR-27b activity, which in turn promotes PPARγ expression and adipogenesis. Enhancement on adipogenesis of adipose tissues is expected to prevent lipotoxicty in nonadipose tissues. Our data may give a better illustration to explain the antidiabetic effect of Rb1 and provide a hint on treatment of lipid related metabolic diseases in the future.
Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong.
L-S
LS
Chan
P Y-K
PY
Yue
T-W
TW
Kok
M-H
MH
Keung
N-K
NK
Mak
R N-S
RN
Wong
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D050156:Adipogenesis / Q000187:drug effects*; D000818:Animals; D005786:Gene Expression Regulation / Q000187:drug effects; D036145:Ginsenosides / Q000494:pharmacology*; D051379:Mice; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D047495:PPAR gamma / Q000235:genetics* / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects*
D036145:Ginsenosides; D035683:MicroRNAs; C540674:Mirn27 microRNA, mouse; D047495:PPAR gamma; D010936:Plant Extracts; C442759:ginsenoside Rb1