Inhibition of adipocyte differentiation by phytoestrogen genistein through a potential downregulation of extracellular signal-regulated kinases 1/2 activity.
In the current study, we investigated the effects of genistein on adipogenic differentiation of mouse bone marrow-derived mesenchymal stem cell (BMSC) cultures and its potential signaling pathway. The terminal adipogenic differentiation was assessed by western-blotting analysis of adipogenic-specific proteins such as PPARgamma, C/EBPalpha, and aP2 and the formation of adipocytes. Treatment of mouse BMSC cultures with adipogenic cocktail resulted in sustained activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), which are members of the mitogen-activated protein kinase (MAPK) family, at the early phase of adipogenesis (from days 3 to 9). Inhibition of ERK1/2 activation by PD98059, a specific MEK inhibitor, reversed the induced adipogenic differentiation. Genistein dose-dependently decreased the phosphorylation of ERK1/2 in mouse BMSC cultures. Genistein incubation for the entire culture period, as well as that applied during the early phase of the culture period, significantly inhibited the adipogenic differentiation of mouse BMSC cultures. While genistein was incubated at the late stage (after day 9), no inhibitory effect on adipogenic differentiation was observed. BMSC cultures treated with genistein in the presence of fibroblast growth factor-2 (FGF-2), an activator of the ERK1/2 signaling pathway, expressed normal levels of ERK1/2 activity, and, in so doing, are capable of undergoing adipogenesis. Our results suggest that activation of the ERK1/2 signaling pathway during the early phase of adipogenesis (from days 3 to 9) is essential to adipogenic differentiation of BMSC cultures, and that genistein inhibits the adipogenic differentiation through a potential downregulation of ERK1/2 activity at this early phase of adipogenesis.
Liao
Qing-Chuan
QC
Nanjing Children's Hospital, Nanjing Medical University, Nanjing 210008, China.
Li
Ya-Lin
YL
Qin
Yan-Fang
YF
Quarles
L Darryl
LD
Xu
Kang-Kang
KK
Li
Rong
R
Zhou
Hong-Hao
HH
Xiao
Zhou-Sheng
ZS
D017667:Adipocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D050156:Adipogenesis / Q000187:drug effects; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects*; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology*; D020935:MAP Kinase Signaling System / Q000187:drug effects; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047495:PPAR gamma; D010766:Phosphorylation / Q000187:drug effects; D048789:Phytoestrogens / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology
D047495:PPAR gamma; D048789:Phytoestrogens; D047428:Protein Kinase Inhibitors; D016222:Fibroblast Growth Factor 2; D019833:Genistein; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3