TMEM16A inhibits angiotensin II-induced basilar artery smooth muscle cell migration in a WNK1-dependent manner

Acta Pharm Sin B. 2021 Dec;11(12):3994-4007. doi: 10.1016/j.apsb.2021.04.013. Epub 2021 Apr 22.

Abstract

Vascular smooth muscle cell (VSMC) migration plays a critical role in the pathogenesis of many cardiovascular diseases. We recently showed that TMEM16A is involved in hypertension-induced cerebrovascular remodeling. However, it is unclear whether this effect is related to the regulation of VSMC migration. Here, we investigated whether and how TMEM16A contributes to migration in basilar artery smooth muscle cells (BASMCs). We observed that AngII increased the migration of cultured BASMCs, which was markedly inhibited by overexpression of TMEM16A. TMEM16A overexpression inhibited AngII-induced RhoA/ROCK2 activation, and myosin light chain phosphatase (MLCP) and myosin light chain (MLC20) phosphorylation. But AngII-induced myosin light chain kinase (MLCK) activation was not affected by TMEM16A. Furthermore, a suppressed activation of integrinβ3/FAK pathway, determined by reduced integrinβ3 expression, FAK phosphorylation and F-actin rearrangement, was observed in TMEM16A-overexpressing BASMCs upon AngII stimulation. Contrary to the results of TMEM16A overexpression, silencing of TMEM16A showed the opposite effects. These in vitro results were further demonstrated in vivo in basilar arteries from VSMC-specific TMEM16A transgenic mice during AngII-induced hypertension. Moreover, we observed that the inhibitory effect of TMEM16A on BASMC migration was mediated by decreasing the activation of WNK1, a Cl--sensitive serine/threonine kinase. In conclusion, this study demonstrated that TMEM16A suppressed AngII-induced BASMC migration, thus contributing to the protection against cerebrovascular remodeling during AngII-infused hypertension. TMEM16A may exert this effect by suppressing the RhoA/ROCK2/MLCP/MLC20 and integrinβ3/FAK signaling pathways via inhibiting WNK1. Our results suggest that TMEM16A may serve as a novel therapeutic target for VSMC migration-related diseases, such as vascular remodeling.

Keywords: AngII, angiotensin II; BASMCs, basilar artery smooth muscle cells; CaCC, Ca2+-activated chloride channel; F-actin, filamentous actin; FAK; FAK, focal adhesion kinase; Hypertension; Integrin; MLC20, myosin light chain 20; MLCK, myosin light chain kinase; MLCP, myosin light chain phosphates; MYPT1, myosin phosphatase target subunit 1; RhoA/ROCK; SMTg, smooth muscle-specific TMEM16A transgenic mice; TMEM16A; VSMC migration; VSMCs, vascular smooth muscle cells; Vascular remodeling; WNK1; WNK1, with-no-lysine kinase 1.