Cyclic GMP Kinase and RhoA Ser188 Phosphorylation Integrate Pro- and Antifibrotic Signals in Blood Vessels ▿ †
AUTOR(ES)
Sawada, Naoki
FONTE
American Society for Microbiology (ASM)
RESUMO
Vascular fibrosis is a major complication of hypertension and atherosclerosis, yet it is largely untreatable. Natriuretic peptides (NPs) repress fibrogenic activation of vascular smooth muscle cells (VSMCs), but the intracellular mechanism mediating this effect remains undetermined. Here we show that inhibition of RhoA through phosphorylation at Ser188, the site targeted by the NP effector cyclic GMP (cGMP)-dependent protein kinase I (cGK I), is critical to fully exert antifibrotic potential. cGK I+/− mouse blood vessels exhibited an attenuated P-RhoA level and concurrently increased RhoA/ROCK signaling. Importantly, cGK I insufficiency caused dynamic recruitment of ROCK into the fibrogenic programs, thereby eliciting exaggerated vascular hypertrophy and fibrosis. Transgenic expression of cGK I-unphosphorylatable RhoAA188 in VSMCs augmented ROCK activity, vascular hypertrophy, and fibrosis more prominently than did that of wild-type RhoA, consistent with the notion that RhoAA188 escapes the intrinsic inhibition by cGK I. Additionally, VSMCs expressing RhoAA188 became refractory to the antifibrotic effects of NPs. Our results identify cGK I-mediated Ser188 phosphorylation of RhoA as a converging node for pro- and antifibrotic signals and may explain how diminished cGMP signaling, commonly associated with vascular malfunction, predisposes individuals to vascular fibrosis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2772562Documentos Relacionados
- Protein kinase A phosphorylation of RhoA mediates the morphological and functional effects of cyclic AMP in cytotoxic lymphocytes.
- The Insert Region of RhoA Is Essential for Rho Kinase Activation and Cellular Transformation
- Salicylates dilate blood vessels through inhibiting PYK2-mediated RhoA/Rho-kinase activation
- Angiotensin II type-1 receptor regulates RhoA and Rho-kinase/ROCK activation via multiple mechanisms. Focus on “Angiotensin II induces RhoA activation through SHP2-dependent dephosphorylation of the RhoGAP p190A in vascular smooth muscle cells”
- RhoGEF Specificity Mutants Implicate RhoA as a Target for Dbs Transforming Activity