JOSD2 inhibits angiotensin II-induced vascular remodeling by deubiquitinating and stabilizing SMAD7

Increased level of angiotensin II (Ang II) plays a central role in the development of hypertensive vascular remodeling. Here, we identify the deubiquitinating enzyme JOSD2 as a protective factor and investigate its molecular mechanism in Ang II-induced vascular remodeling. Firstly, we found that JOSD2 was up-regulated in aortic smooth muscle cells but not endothelial cells of Ang II-challenged mouse vascular tissues. Whole-body knockout of JOSD2 significantly deteriorated Ang II-induced vascular remodeling in mice. Conversely, Ang II-induced vascular remodeling was reversed by VSMC-specific JOSD2 overexpression. In vitro, JOSD2 deficiency aggravated the fibrosis, proliferation, and migration induced by Ang II in vascular smooth muscle cells (VSMCs), while these changes were reversed by JOSD2 overexpression. RNA-seq analysis showed that the protective effects of JOSD2 in VSMCs were related to TGFβ-SMAD pathway. Furthermore, the LC-MS/MS analysis identified SMAD7, a negative regulator in TGFβ-SMAD pathway, as the substrate of JOSD2. JOSD2 specifically bound to the MH1 domain of SMAD7 to removed K48-linked Ub chains of SMAD7 at lysine 220 to sustain SMAD7 stability. Taken together, our finding reveals that JOSD2-SMAD7 axis is critical for relieving Ang II-induced vascular remodeling and JOSD2 maybe a novel and potential therapeutic target for hypertensive vascular remodeling.