Enhanced effects of 1,25(OH)(2)D(3) plus genistein on adipogenesis and apoptosis in 3T3-L1 adipocytes.
OBJECTIVE
To investigate the ability of 1,25(OH)(2)D(3) (D) and genistein (G), alone and in combination, to inhibit adipogenesis and induce apoptosis in 3T3-L1 adipocytes.


METHODS
3T3-L1 preadipocytes and mature adipocytes were incubated with various concentrations of D and G, alone and in combination, for 48 h. Viability was determined using the Cell Titer 96 Aqueous One Solution Cell Proliferation Assay. Post-confluent preadipocytes were incubated with D and G for up to 6 days during adipogenesis and lipid content was quantified by Nile Red dye; apoptosis was quantified by measurement of single-stranded DNA. Expression of adipocyte-specific proteins and VDR was analyzed by western blotting.


RESULTS
Combining D and G did not cause an enhanced effect on cell viability in either preadipocytes or mature adipocytes. In maturing preadipocytes, D at 0.5 nmol/l (D0.5) increased apoptosis by 47 +/- 10.25% (P < 0.05) and inhibited lipid accumulation by 28 +/- 10% (P < 0.001), while G at 25 micromol/l (G25) had no significant effect. However, D+G caused an enhanced apoptosis by 136 +/- 12.6% (P < 0.001) and enhanced inhibition of lipid accumulation by 82.46 +/- 2.95% (P < 0.001). Similarly, D0.5 alone decreased adipose-specific gene 422 (aP2) expression to 34.2 +/- 2.3% and increased VDR expression levels by 41.8 +/- 11% (P < 0.001), but G25 showed no effect. However, D0.5+G25 decreased aP2 expression to 52 +/- 4.2% (P < 0.05) and increased VDR expression levels by 131 +/- 14.5% (P < 0.0001).


CONCLUSIONS
These findings suggest that combining 1,25(OH)(2)D(3) with genistein results in an enhanced inhibition of lipid accumulation and induction of apoptosis in maturing 3T3-L1 preadipocytes.
Rayalam
Srujana
S
Department of Animal and Dairy Science, University of Georgia, Athens, GA, USA.
Della-Fera
Mary Anne
MA
Ambati
Suresh
S
Yang
Jeong-Yeh
JY
Park
Hea Jin
HJ
Baile
Clifton A
CA
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D050156:Adipogenesis / Q000187:drug effects*; D000818:Animals; D019440:Anti-Obesity Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D022763:CCAAT-Enhancer-Binding Protein-alpha / Q000378:metabolism; D002117:Calcitriol / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D050556:Fatty Acid-Binding Proteins / Q000378:metabolism; D019833:Genistein / Q000494:pharmacology*; D050356:Lipid Metabolism / Q000187:drug effects; D051379:Mice; D047495:PPAR gamma / Q000378:metabolism; D018167:Receptors, Calcitriol / Q000378:metabolism; D013997:Time Factors
D019440:Anti-Obesity Agents; D022763:CCAAT-Enhancer-Binding Protein-alpha; C493411:Fabp4 protein, mouse; D050556:Fatty Acid-Binding Proteins; D047495:PPAR gamma; D018167:Receptors, Calcitriol; D019833:Genistein; D002117:Calcitriol