C反应蛋白对3T3-L1脂肪细胞内高分子量多聚体脂联素表达和脂联素多聚化水平的影响

Effects of C-reactive protein on the expression of high-molecular-weight adiponectin and assembly of adiponectin

目的 C反应蛋白(C-reactive protein,CRP)作为炎症因子在糖尿病等代谢相关疾病早期即显著升高,而脂联素具有抗炎、抗糖尿病、抗动脉粥样硬化,在糖尿病疾病中表达水平下降。探讨CRP对3T_3-L1脂肪细胞内高分子量多聚体脂联素(high molecular weight adiponectin,HMWA)和脂联素多聚化水平的影响。方法选用3T_3-L1脂肪前体细胞株,诱导分化成熟后,50μg/m L CRP刺激0、6、12、24 h后或0、5、25、50μg/m L刺激24 h分别收集蛋白,通过Western blot方法检测HMWA表达。0、50μg/m L刺激24 h后,实时定量PCR检测脂联素多聚化相关调控基因(Ero1-L、Dsb A-L、ERp44)水平。结果与0μg/m L的CRP对HMWA的表达量(1.00±0.00)比较,5μg/m L的表达量(0.88±0.17)有所下降(P>0.05),而25、50μg/m L的相对表达量(0.70±0.07、0.44±0.07)明显下降(P<0.05)。与CRP诱导0 h脂联素表达(1.00±0.00)比较,诱导6 h的表达(0.84±0.07)差异无统计学意义(P>0.05),而诱导12、24 h后,脂联素表达(0.71±0.06、0.48±0.11)明显下降(P<0.05)。与CRP 0μg/m L相比,CRP 50μg/m L刺激24 h后,Ero1-L基因、Dsb A-L表达降低,而ERp44显著升高(P<0.05)。结论 CRP通过减少HMWA的表达以及抑制脂联素多聚化以减弱脂联素在疾病中所起的积极作用,从而部分参与了CRP加速炎症相关代谢疾病的发生发展。

Objective C reactive protein（ CRP）,an inflammatory maker, increased significantly among diabetes mellitus and other metabolic diseases. Meanwhile,adiponectin plays a vital role in anti-atherogenic,anti-inflammatory and anti-diabetic potentials. Further,it decreased in diabetes mellitus. To investigate the effects of C-reactive protein in the expression of high-molecular-weight adiponectin（ HMWA） and adiponectin multimerization. Methods The fully differentiated 3T_3-L1 cells were respectively treated with 50μg /m L CRP for 0 h、6 h、12 h and 24 h,and different doses of CRP with 0 μg / m L、5 μg / m L、25 μg / m L、50 μg / m L for 24 h. The expression of HMWA was further detected by Western blot. Additionally,the mRNA expressions of adiponectin assembly related genes（ Ero1-L、Dsb A-L、ERp44） were detected by Real time PCR after 50μg /m L CRP treatment for 24 h. Results After 24 h treatment,25 μg /m L CRP and 50μg /m L CRP resulted in a substantial reduction（ [70 ± 7]% vs [44 ± 7]%,P 0. 05） while 5 μg/m L CRP revealed no change. With the dose of 50 μg/m L CRP treated,the expression of HWMA were both inhibited after the 12 h and 24 h CRP treatment（ [71 ± 6]% vs [48 ± 11]%,P 0. 05）,but for the 6h CRP treatment group,HWMA remained unchanged. Additionally,CRP inhibited Ero1-L（ 86 ± 10） % and Dsb A-L（ 72 ± 6） % gene expression and upregulated the expression of ERp44（ 141 ± 23） %. Conclusion CRP decreases HMWA expression in a dose and time-dependent manner and inhibits the multimerization of adiponectin,thus weaken the benefits of adiponectin in diabetes.