ROCK1 mediates leukocyte recruitment and neointima formation following vascular injury.
ABSTRACT Although Rho-associated kinase (ROCK) activity has been implicated in cardiovascular diseases, the tissue- and isoform-specific roles of ROCKs in the vascular response to injury are not known. To address the role of ROCKs in this process, we generated haploinsufficient Rock1 (Rock1(+/-)) and Rock2 (Rock2(+/-)) mice and performed carotid artery ligations. Following this intervention, we found reduced neointima formation in Rock1(+/-) mice compared with that of WT or Rock2(+/-) mice. This correlated with decreased vascular smooth muscle cell proliferation and survival, decreased levels proinflammatory adhesion molecule expression, and reduced leukocyte infiltration. In addition, thioglycollate-induced peritoneal leukocyte recruitment and accumulation were substantially reduced in Rock1(+/-) mice compared with those of WT and Rock2(+/-) mice. To determine the role of leukocyte-derived ROCK1 in neointima formation, we performed reciprocal bone marrow transplantation (BMT) in WT and Rock1(+/-) mice. Rock1(+/-) to WT BMT led to reduced neointima formation and leukocyte infiltration following carotid ligation compared with those of WT to WT BMT. In contrast, WT to Rock1(+/-) BMT resulted in increased neointima formation. These findings indicate that ROCK1 in BM-derived cells mediates neointima formation following vascular injury and suggest that ROCK1 may represent a promising therapeutic target in vascular inflammatory diseases.
- SourceAvailable from: Rong Jin[Show abstract] [Hide abstract]
ABSTRACT: Although TAK1 has been implicated in inflammation and oxidative stress, its roles in vascular smooth muscle cells (VSMCs) and in response to vascular injury have not been investigated. The present study aimed to investigate the role of TAK1 in modulating oxidative stress in VSMCs and its involvement in neointima formation after vascular injury. Double immunostaining reveals that vascular injury induces a robust phosphorylation of TAK1 (Thr187) in the medial VSMCs of injured arteries in wildtype mice, but this effect is blocked in CD40-deficient mice. Upregulation of TAK1 in VSMCs is functionally important, as it is critically involved in pro-oxidative and pro-inflammatory effects on VSMCs and eventual neointima formation. In vivo, pharmacological inhibition of TAK1 with 5Z-7-oxozeaenol blocked the injury-induced phosphorylation of both TAK1 (Thr187) and NF-kB/p65 (Ser536), associated with marked inhibition of superoxide production, 3-nitrotyrosine, and MCP-1 in the injured arteries. Cell culture experiments demonstrated that either siRNA knockdown or 5Z-7-oxozeaenol inhibition of TAK1 significantly attenuated NADPH oxidase activation and superoxide production induced by CD40L/CD40 stimulation. Co-immunoprecipitation experiments indicate that blockade of TAK1 disrupted the CD40L-induced complex formation of p22phox with p47phox, p67phox, or Nox4. Blockade of TAK1 also inhibited CD40L-induced NF-kB activation by modulating IKKα/β and NF-kB p65 phosphorylation and this was related to reduced expression of proinflammatory genes (IL-6, MCP-1 and ICAM-1) in VSMCs. Lastly, treatment with 5Z-7-oxozeaenol attenuated neointimal formation in wire-injured femoral arteries. Our findings demonstrate previously uncharacterized roles of TAK1 in vascular oxidative stress and the contribution to neointima formation after vascular injury.PLoS ONE 07/2014; 9(7):e101671. · 3.53 Impact Factor
- International Journal of Cardiology 07/2014; · 6.18 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Rho-associated kinase (ROCK) signaling pathway has been shown to mediate various cellular functions including cell proliferation, migration, adhesion, apoptosis, and contraction, all of which may be involved in pathogenesis of atherosclerosis. Endogenous nitric oxide (NO) is well known to have an anti-atherosclerotic effect, whereas the exogenous NO-mediated cardiovascular effect still remains controversial. The purpose of this study was to evaluate the effect of exogenous NO on ROCK activity in vascular smooth muscle cells (VSMCs) in vitro and in vivo.PLoS ONE 10/2014; 9(10):e109017. · 3.53 Impact Factor