HDL和阿托伐他汀对oxLDL刺激下脂肪细胞炎症反应的影响

Influences of high density lipoprotein and atorvastatin on inflammatory reaction in 3T3-L1 adipocytes stimulated by oxLDL

目的观察高密度脂蛋白(HDL)及阿托伐他汀对氧化型低密度脂蛋白(oxLDL)刺激下3T3-L1脂肪细胞肿瘤坏死因子-α(TNFα)分泌及mRNA表达的影响,并探讨其可能的作用机制。方法 3T3-L1脂肪细胞促分化成熟后,oxLDL刺激脂肪细胞,给予不同浓度的HDL(10～100μg/mL)和阿托伐他汀(0.1～10μM),及H-89(10μM)+HDL(100μg/mL)干预,收集细胞,测定脂肪细胞TNFα水平、TNFα mRNA表达水平、核因子-κB(NF-κB)活性及NF-κB抑制单位(IκB)蛋白浓度。结果 oxLDL刺激使3T3-L1脂肪细胞TNFα分泌、mRNA表达水平及NF-κB活性明显增强。阿托伐他汀浓度依赖性降低TNFα分泌及mRNA表达,抑制NF-κB活化。10μM阿托伐他汀使oxLDL诱导的脂肪细胞TNFαmRNA表达降低56.5%,NF-κB活性减少41.2%。HDL也呈浓度依赖性抑制TNFα分泌及mRNA表达,降低NF-κB活性,减少IκB降解。与oxLDL刺激组比较,100μg/mlHDL使TNFαmRNA表达降低64.5%,NF-κB活性减少49%,并明显增加IκB蛋白水平。HDL的这些抗炎效应能被蛋白激酶A(PKA)抑制剂(应放在H89第一次出现之处)H-89部分抑制。结论 HDL能抑制oxLDL诱导的3T3-L1脂肪细胞TNFα分泌和mRNA表达,PKA-IκB-NF-κB信号通路可能是其中作用途径之一,该效应不需要HDL与oxLDL的直接接触作用。阿托伐他汀亦通过NF-κB途径抑制oxLDL诱导的3T3-L1脂肪细胞TNFα分泌和mRNA表达。HDL的抗炎作用强度与阿托伐他汀相似。

Objective To observe high density lipoprotein （HDL） and atorvastatin on the secretion and mR- NA expression of tumor necrosis factor-or （TNF-α） in 3T3-L1 adipocytes stimulated by oxidized low density lipoprotein （oxLDL）, and discuss the possible mechanism. Methods After differentiating and maturing, T3-L1 adipocytes were stimulated by oxLDL and given different doses of HDL （10-100 μg/mL） and atorvastatin （0. 1-10 μM ）, and then intervened with H-89 [ the inhibitor of protein kinase A （PKA）, 10 μM] and HDL （100 μg/mL）. 3T3-L1 adi- pocytes were collected for detecting TNF-α level, expression of TNF-α mRNA, activity of nuclear factor-kappa B （ NF- κB） and protein concentration of NF-κB inhibition unit-IκB. Results The stimulation of oxLDL improved signifi- cantly the secretion of TNF-α, expression of TNF-α mRNA and activity of NF-κB in 3T3-L1 adipocytes. Atorvastatin reduced the secretion of TNF-α, expression of TNF-α mRNA and activation of NF-κB in a dose-dependent manner. Atorvastatin in the dose of 10 μM reduced the expression of TNF-α mRNA by 56.5% and activity of NF-κB by 41.2%. HDL also inhibited the secretion of TNF-α, expression of TNF-α mRNA and activity of NF-κB, and reduced the degradation of IκB in a dose-dependent manner. Compared with the stimulation of oxLDL, HDL in the dose of 100 μg/mL reduced the expression of TNF-α mRNA by 64.5% , activity of NF-κB by 49% and increased significantly pro- tein level of IκB. The anti-inflammatory effect of HDL could be partially inhibited by H-89. Conclusion HDL can inhibit the secretion of TNF-α and expression of TNF-α mRNA induced by oxLDL in 3T3-L1 adipocytes, and the signal pathway of PKA-IκB-NF-κB maybe one of its function ways, in which HDL and oxLDL have no any contact. Atorvasta- tin inhibits the secretion of TNF-α and expression of TNF-α mRNA induced by oxLDL in 3T3-L1 adipoeytes through NF-κB pathway. The intensity of anti-inflammatory effect of HDL is similar to that of atorvastatin.