Rayalam Srujana, Della-Fera Mary Anne, Ambati Suresh, Yang Jeong-Yeh, Park Hea Jin, Baile Clifton A
Department of Animal and Dairy Science, University of Georgia, Athens, GA, USA.
Obesity (Silver Spring). 2008 Mar;16(3):539-46. doi: 10.1038/oby.2007.90. Epub 2008 Jan 17.
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.
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.
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).
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.
研究1,25(OH)₂D₃（D）和染料木黄酮（G）单独及联合使用时抑制3T3-L1脂肪细胞脂肪生成和诱导其凋亡的能力。
将3T3-L1前脂肪细胞和成熟脂肪细胞分别用不同浓度的D和G单独及联合处理48小时。使用细胞增殖检测试剂盒（Cell Titer 96 Aqueous One Solution Cell Proliferation Assay）测定细胞活力。在脂肪生成过程中，将汇合后的前脂肪细胞与D和G孵育长达6天，并用尼罗红染料定量脂质含量；通过测量单链DNA定量凋亡情况。通过蛋白质免疫印迹法分析脂肪细胞特异性蛋白和维生素D受体（VDR）的表达。
D和G联合使用对前脂肪细胞或成熟脂肪细胞的细胞活力均未产生增强作用。在正在成熟的前脂肪细胞中，0.5 nmol/l的D（D0.5）使凋亡增加47±10.25%（P<0.05），脂质积累抑制28±10%（P<0.001），而25 μmol/l的G（G25）无显著影响。然而，D+G使凋亡增加136±12.6%（P<0.001），脂质积累抑制增强82.46±2.95%（P<0.001）。同样，单独的D0.5使脂肪特异性基因422（aP2）表达降至34.2±2.3%，VDR表达水平增加41.8±11%（P<0.001），但G25无作用。然而，D0.5+G25使aP2表达降至52±4.2%（P<0.05），VDR表达水平增加131±14.5%（P<0.0001）。
这些发现表明，1,25(OH)₂D₃与染料木黄酮联合使用可增强对正在成熟的3T3-L1前脂肪细胞脂质积累的抑制作用并诱导其凋亡。
