Tributyltin triggers lipogenesis in macrophages via modifying PPARγ pathway. (15th February 2021)

• Record Type: Journal Article
• Authors: Jie, Jiapeng; Ling, Ling; Yi, Yuguo; Tao, Liang; Liao, Xin; Gao, Pingshi; Xu, Qian; Zhang, Weigao; Chen, Yuxin; Zhang, Jianfa; Weng, Dan
• Is Part Of: Environmental pollution. Volume 271(2021)
• Publication Date: 2021-02-15
• Subjects: TBT -- PPARγ -- Macrophages -- Lipogenesis; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.116331
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Tributyltin (TBT), a bioaccumulative and persistent environmental pollutant, has been proposed as a metabolism disruptor and obesogen through targeting peroxisome proliferator-activated receptor gamma (PPARγ) receptor pathway. However, it remains unknown whether this biological effect occurs in macrophage, a cell type which cooperates closely with hepatocytes and adipocytes to regulate lipid metabolism. This study for the first time investigated the effect of TBT on PPARγ pathway in macrophages. Our results indicated that nanomolar levels of TBT was able to strongly activate PPARγ in human macrophages. TBT treatment also markedly increased the intracellular lipid accumulation, and enhanced the expression of lipid metabolism-related genes in macrophages, while these effects were all significantly down-regulated in PPARγ-deficient macrophages, confirming the involvement of PPARγ in TBT-induced lipogenesis. Next, a mouse model that C57BL/6 mice were orally exposed to TBT with the doses (250 and 500 μg/kg body weight) lower than NOAEL (no observed adverse effect level) was used to further investigate the in vivo mechanisms. And the in vivo results were consistent with cellular assays, confirming the induction of PPARγ and the increased expression of lipogenesis-regulating and lipid metabolism-related genes by TBT in vivo. In conclusion, this study not only provided the first evidence that TBT stimulated lipogenesis, activated PPARγ and related genes in human macrophages, but also provided insight into the mechanism of TBT-induced metabolism disturbance and obesity through targeting PPARγ via both in vitro cellular assays and in vivo animal models. Graphical abstract: Image 1 Highlights: Nanomolar levels of TBT strongly activated PPARγ in human macrophages. TBT prompted lipid accumulation in macrophages via PPARγ and lipogenesis pathway. Subchronic TBT exposure increased the mouse body weight gain. TBT induced the expression of PPARγ and its target genes in mouse Kupffer cells.