FAT/CD36在高脂喂养小鼠脂肪组织炎症中的作用

目的:探讨脂肪酸转运酶/白细胞分化抗原36(fatty acid translocase/CD36,FAT/CD36)在高脂饮食诱导的小鼠脂肪组织炎症中的作用。方法:将6周龄雄性C57BL/6J小鼠分别随机分为普通饮食组和高脂饮食组,喂养14周后,ELISA测定血清游离脂肪酸(FFA)含量,应用荧光实时定量PCR和Western blotting检测脂肪组织中FAT/CD36及炎症/趋化因子(IL-1β、IL-6、TNF-α、MCP-1、MIP-1)mRNA和蛋白的表达,免疫组织化学染色检测脂肪组织巨噬细胞浸润,比较高脂喂养14周的野生型小鼠和CD36基因敲除小鼠的脂肪组织炎症反应情况。结果:与普通饮食组相比,高脂饮食能增强C57BL/6J小鼠脂肪组织的FAT/CD36及炎症/趋化因子的表达,促进巨噬细胞在脂肪组织的浸润。与高脂饮食喂养的野生型小鼠相比,CD36基因敲除小鼠的脂肪组织炎症因子、趋化因子表达明显降低,脂肪组织巨噬细胞浸润减少。结论:高脂饮食通过上调脂肪组织FAT/CD36的表达激活了脂肪组织炎症。

Role of FAT/CD36 in high-fat diet-induced adipose tissue inflammation

AIM: To investigate the role of fatty acid translocase/CD36 (FAT/CD36) in adipose tissue inflammation induced by a high-fat diet. METHODS: C57BL/6J mice were fed with a normal-chow diet (NCD) or a high-fat diet (HFD) for 14 weeks. The content of free fatty acid (FFA) in the serum was measured by ELISA. The expression of CD36, cytokines and chemokines at mRNA and protein levels in the adipose tissues was determined by real-time polymerase chain reaction and Western blotting. Immunohistochemical staining was used to examine the macrophages infiltration in the adipose tissues. The inflammatory responses in CD36 knockout mice and wild type mice with high-fat diet were analyzed. RESULTS: The levels of FAT/CD36 were higher in HFD group than that in NCD group. HFD feeding enhanced the mRNA and protein expression of IL-1β, IL-6, TNF-α, MCP-1 and MIP-1, as well as promoted macrophage infiltration in the adipose tissues. Interestingly, as fed with HFD, the expression of cytokines/chemokines and macrophage infiltration were significantly reduced in adipose tissues of the CD36 knockout mice, compared with the wild type mice. CONCLUSION: High-fat diet promotes adipose tissue inflammation in the mice in a FAT/CD36-dependent manner.