Ⅱ型钙调蛋白激酶δ亚基基因在3T3-L1脂肪细胞诱导分化中的表达及肿瘤坏死因子-α调控作用

Expression of Calcium/Calmodulin - Dependent Protein Kinase Ⅱ Gene in 3T3 - L1 Preadipocyte Differentiation and Regulation of Timor Necrosis Factor- α

目的观察3T3-L1前体脂肪细胞诱导分化过程中Ⅱ型钙调蛋白激酶δ亚基基因表达水平及肿瘤坏死因子-α对成熟脂肪细胞中Ⅱ型钙调蛋白激酶δ亚基((2AMKⅡD)基因表达的调控作用。方法检测3T3-L1前体脂肪细胞体外诱导分化不同时段CAMKⅡD基因的mRNA表达水平;采用不同浓度TNF-α干预成熟脂肪细胞,检测干预后不同时间点CAMKⅡD基因的表达水平。结果3T3-L1前体脂肪细胞中CAMKⅡD基因mRNA表达,于d1显著下调,与d0比较具有显著差异(P< 0.01);d2其表达水平显著上调,并明显高于d0表达水平(P<0.01);d2-10表达一直维持在较高水平(P>0.05)。0.1、1.0 μg/L的TNF-α干预后,成熟脂肪细胞该基因各时段的表达水平无显著变化(P>0.05);10.0 μg/L的TNF-α干预后,在12 h 始,其表达水平有显著性下调(P<0.01);其他各时段之间无显著变化(P>0.05)。结论CAMKⅡD基因参与脂肪细胞分化的调控,与肥胖发生相关,其在3T3-L1细胞分化过程中的表达变化可能有利于脂肪细胞的分化成熟和脂质积聚。TNF-α对成熟脂肪细胞中CAMKⅡD基因表达可能不具有调控作用。

Objective To investigate the changes of calcium /ealnlodulin- dependent proteinkinase Ⅱ（CAMK ⅡD） geneexpression in 3T3 - L1 preadipocyte diffe-rentiation and TNF - α regulation of CAMK ]ID gene expression on matured adipocytes. Methods 3T3 - L1 preadipocytes were cultured and differentiated into adipocytes. The levels of CAMK Ⅱ D gene mRNA expression at various times were evaluated by RT - PCR. Matured adipocytes were interfered with 0.1,1.0,10.0 p.g/L TNF- c~ and the levels of CAMK ⅡD gene mRNA expression were evaluated. Results The levels of CAMK ⅡD gene mRNA expression in 3T3 - L1 adipocytes were significantly down - regulated at first day, compared with those at zero day （P〈0.01）. However, the subsequently marked up- regulation of it was observed at .second day. Compatred with that at zero day, it was significantly higher（ P〈 0.01 ） at second day. Thereafter, it renmined high from .second day to tenth day, without signific.ant difference between two detected phases（ P 〉 0.05 ）. CAMK Ⅱ D gene mRNA expresion deereased significantly at 12 hours after treatment with 10.0 p.g/L TNF- α, treatment of matured adipocytes with TNF - α did not have any regulation role on it. Conclusions CAIVIK ⅡD gene is involved in the differentiation of adipocytes and related to the etiology of obesity. The changes in the level of CAMK ⅡD gene mRNA expression during 3T3 - L1 preadlpocyte differentation may comribute to the differentiation and aditx,genesis of adipocytes. It seems that TNF- α does not have any regulalion role on the expression of CAMK ⅡD genes.