摘要
目的探究黏膜相关恒定T(MAIT)细胞与脂肪棕色化之间的关系以及调节脂肪棕色化的分子机制。方法构建MAIT细胞功能缺陷小鼠模型,对比野生型小鼠及MAIT细胞缺陷小鼠,通过Westernblot和RT-PCR检测冷刺激前后小鼠脂肪棕色化标志物的水平差异,并通过流式细胞术检测了小鼠脂肪组织内MAIT细胞在冷刺激前后数量、活化水平以及细胞因子分泌能力的差异。采用MAIT细胞与脂肪细胞共培养的方式,通过Westernblot和RT-PCR检测是否存在MAIT细胞以及是否加入白介素4(IL-4)封闭抗体的条件下脂肪细胞棕色化标志物的表达差异。利用MAIT细胞缺陷的小鼠模型,通过代谢笼、免疫组化、Westernblot和Seahorse方法检测MAIT细胞缺陷小鼠在冷刺激条件下的脂肪棕色化相关指标。结果Westernblot和RT-PCR结果显示小鼠冷刺激后脂肪组织棕色化标志物UCP-1、PGC1-α的表达水平均上调,在此情景下小鼠脂肪组织内MAIT细胞数量差异无统计学意义(P>0.05),CD69的表达水平上调(P<0.05),效应细胞因子IL-4的表达水平上调(P<0.05)。体外共培养实验显示,脂肪细胞与MAIT细胞共培养后的棕色化水平上调(P<0.05),若阻断IL-4信号则棕色化水平下调(P<0.05)。对MAIT细胞缺陷的小鼠进行冷刺激后,其能量消耗水平低于野生型小鼠(P<0.05),脂肪棕色化水平低于野生型小鼠(P<0.05),且脂肪细胞代谢水平低于野生型小鼠。结论本研究首次通过MAIT细胞功能缺陷小鼠模型验证MAIT细胞参与脂肪棕色化,动物实验及体外实验进一步显示冷刺激通过促进MAIT细胞分泌IL-4调控脂肪细胞棕色化。
Objective To investigate the role of mucosal-associated invariant T(MAIT)cells in the regulatory mechanism of adipose browning.Methods A mouse model with functional deficiency of MAIT cells was established for comparison with the wild-type mice for levels of brown adipose tissue markers in response to cold stimulation using Western blotting and RT-PCR.Flow cytometry was used to analyze the changes in the number,activation level and cytokine secretion ability of MAIT cells in mouse adipose tissue after cold stimulation.In a co-culture system of MAIT cells and adipocytes,the effect of interleukin-4(IL-4)blocking antibodies on the expressions of brown adipose tissue markers in the adipocytes was evaluated using Western blotting and RT-PCR.In a mouse model of MAIT cell deficiency,the changes in adipose browning-related indicators in response to cold stimulation were analyzed using metabolic cages,immunohistochemistry,Western blotting and the Seahorse method.Results In both the mouse models of functional deficiency of MAIT cells and wild-type mice,cold stimulation significantly increased the expression levels of brown adipose tissue markers UCP-1 and PGC1-αand upregulated CD69 and IL-4 expressions in the adipose tissue without significantly affecting the number of MAIT cells in the adipose tissue.In the co culture experiment,the adipocytes showed obviously increased browning level after co-culture with MAIT cells(P<0.05),but blocking IL-4 signaling strongly downregulated the browning level(P<0.05).The MAIT cell-deficient mice showed obviously lower levels of energy expenditure,adipose browning and metabolism of the adipocytes compared with the wild-type mice in response to cold stimulation(P<0.05).Conclusion MAIT cells participate in adipose browning in mice,and cold stimulation promotes MAIT cell secretion of IL-4 to positively regulate adipose browning.
作者
叶潇
宋迎香
赵瑜
朱大龙
YE Xiao;SONG Yingxiang;ZHAO Yu;ZHU Dalong(Department of Endocrinology,Drum Tower Hospital Clinical College of Nanjing Medical University,Nanjing 210008,China;Department of Endocrinology,Zhejiang Provincial People's Hospital(Affiliated People's Hospital of Hangzhou Medical College),Hangzhou 310014,China)
出处
《南方医科大学学报》
CAS
CSCD
北大核心
2023年第11期1881-1885,共5页
Journal of Southern Medical University
基金
国家自然科学基金(82100911)
浙江省自然科学基金(LY19H070002)。
关键词
黏膜相关恒定T细胞
肥胖
棕色脂肪
mucosal-associated invariant T cells
obesity
brown adipose tissue
