1. Academic Validation
  2. PP2Acα promotes macrophage accumulation and activation to exacerbate tubular cell death and kidney fibrosis through activating Rap1 and TNFα production

PP2Acα promotes macrophage accumulation and activation to exacerbate tubular cell death and kidney fibrosis through activating Rap1 and TNFα production

  • Cell Death Differ. 2021 Sep;28(9):2728-2744. doi: 10.1038/s41418-021-00780-5.
Yan Liang 1 Xiaoli Sun 2 Mingjie Wang 1 Qingmiao Lu 1 Mengru Gu 1 Lu Zhou 1 Qing Hou 1 Mengzhu Tan 1 Sudan Wang 1 Xian Xue 2 Chunsun Dai 3 4
Affiliations

Affiliations

  • 1 Center for Kidney Disease, the 2nd Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
  • 2 Department of Clinical Genetics, the 2nd Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China.
  • 3 Center for Kidney Disease, the 2nd Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China. [email protected].
  • 4 Department of Clinical Genetics, the 2nd Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu, China. [email protected].
Abstract

Macrophage accumulation and activation play an essential role in kidney fibrosis; however, the underlying mechanisms remain to be explored. By analyzing the kidney tissues from patients and animal models with kidney fibrosis, we found a large induction of PP2Acα in macrophages. We then generated a mouse model with inducible macrophage ablation of PP2Acα. The knockouts developed less renal fibrosis, macrophage accumulation, or tubular cell death after unilateral ureter obstruction or ischemic reperfusion injury compared to control littermates. In cultured macrophages, PP2Acα deficiency resulted in decreased cell motility by inhibiting Rap1 activity. Moreover, co-culture of PP2Acα-/- macrophages with tubular cells resulted in less tubular cell death attributed to downregulated Stat6-mediated tumor necrosis factor α (TNFα) production in macrophages. Together, this study demonstrates that PP2Acα promotes macrophage accumulation and activation, hence accelerates tubular cell death and kidney fibrosis through regulating Rap1 activation and TNFα production.

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