[Show abstract][Hide abstract] ABSTRACT: The RhoA/Rho-associated kinase (ROCK) pathway has a key physiological role in the pathogenesis of atherosclerosis. Increased ROCK activity is associated with cardiovascular diseases. Endogenous nitric oxide (NO) has 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 patients with angina pectoris. This is a prospective, open-label, randomized, controlled study. A total of 30 patients with angina pectoris were randomly assigned to receive 40 mg day(-1) of isosorbide mononitrate (n=15, 12 men and 3 women, mean age of 63±12 years, isosorbide mononitrate group) or conventional treatment (n=15, 13 men and 2 women, mean age of 64±13 years, control group) for 12 weeks. ROCK activity in peripheral leukocytes was measured by western blot analysis. ROCK activities at 4 and 12 weeks after treatment were decreased in the isosorbide mononitrate group (0.82±0.33 at 0 week, 0.62±0.20 at 4 weeks, 0.61±0.19 at 12 weeks, n=15 in each group, P<0.05, respectively) but not altered in the control group. ROCK1 and ROCK2 expression levels were similar in all treatment periods in the two groups. These findings suggest that the administration of exogenous NO can inhibit ROCK activity, indicating that the usage of exogenous NO could have a protective effect in patients with angina pectoris.Hypertension Research advance online publication, 5 March 2015; doi:10.1038/hr.2015.24.
No preview · Article · Mar 2015 · Hypertension Research
[Show abstract][Hide abstract] ABSTRACT: Idiopathic pulmonary fibrosis (IPF) is characterized by progressive lung scarring, short median survival, and limited therapeutic options, creating great need for new pharmacologic therapies. IPF is thought to result from repetitive environmental injury to the lung epithelium, in the context of aberrant host wound healing responses. Tissue responses to injury fundamentally involve reorganization of the actin cytoskeleton of participating cells, including epithelial cells, fibroblasts, endothelial cells, and macrophages. Actin filament assembly and actomyosin contraction are directed by the Rho-associated coiled-coil forming protein kinase (ROCK) family of serine/threonine kinases (ROCK1 and ROCK2). As would therefore be expected, lung ROCK activation has been demonstrated in humans with IPF and in animal models of this disease. ROCK inhibitors can prevent fibrosis in these models, and more importantly, induce the regression of already established fibrosis. Here we review ROCK structure and function, upstream activators and downstream targets of ROCKs in pulmonary fibrosis, contributions of ROCKs to profibrotic cellular responses to lung injury, ROCK inhibitors and their efficacy in animal models of pulmonary fibrosis, and potential toxicities of ROCK inhibitors in humans, as well as involvement of ROCKs in fibrosis in other organs. As we discuss, ROCK activation is required for multiple profibrotic responses, in the lung and multiple other organs, suggesting ROCK participation in fundamental pathways that contribute to the pathogenesis of a broad array of fibrotic diseases. Multiple lines of evidence therefore indicate that ROCK inhibition has great potential to be a powerful therapeutic tool in the treatment of fibrosis, both in the lung and beyond.
No preview · Article · Jan 2015 · Pharmacological reviews
[Show abstract][Hide abstract] ABSTRACT: Objective
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.
VSMCs migration was evaluated using a modified Boyden chamber assay. ROCK activities were measured by Western blot analysis in murine and human VSMCs and aorta of mice treated with or without angiotensin II (Ang II) and/or sodium nitroprusside (SNP), an NO donor.
Co-treatment with SNP inhibited the Ang II-induced cell migration and increases in ROCK activity in murine and human VSMCs. Similarly, the increased ROCK activity 2 weeks after Ang II infusion in the mouse aorta was substantially inhibited by subcutaneous injection of SNP.
These findings suggest that administration of exogenous NO can inhibit ROCK activity in VSMCs in vitro and in vivo.
[Show abstract][Hide abstract] ABSTRACT: Background
Major features of allergic asthma include airway hyperresponsiveness (AHR), eosinophilic inflammation, and goblet cell metaplasia. Rho kinase (ROCK) is a serine/threonine protein kinase that regulates the actin cytoskeleton. By doing so, it can modulate airway smooth muscle cell contraction and leukocyte migration and proliferation. This study was designed to determine the contributions of the two ROCK isoforms, ROCK1 and ROCK2, to AHR, inflammation and goblet cell metaplasia in a mast-cell dependent model of allergic airways disease.Methods and ResultsRepeated intranasal challenges with OVA caused AHR, eosinophilic inflammation, and goblet cell hyperplasia in wildtype (WT) mice. OVA- induced AHR was partially or completely abrogated in mice haploinsufficient for ROCK2 (ROCK2+/-) or ROCK1 (ROCK1+/-), respectively. In contrast, there was no effect of ROCK insufficiency on allergic airways inflammation, although both ROCK1 and ROCK2 insufficiency attenuated mast cell degranulation. Goblet cell hyperplasia, as indicated by PAS staining, was not different in ROCK1+/- versus WT mice. However, in ROCK2+/- mice, goblet cell hyperplasia was reduced in medium but not large airways. Maximal acetylcholine-induced force generation was reduced in tracheal rings from ROCK1+/- and ROCK2+/- versus WT mice. The ROCK inhibitor, fasudil, also reduced airway responsiveness in OVA-challenged mice, without affecting inflammatory responses.Conclusion
In a mast cell model of allergic airways disease, ROCK1 and ROCK2 both contribute to AHR, likely through direct effects on smooth muscle cell and effects on mast-cell degranulation. In addition, ROCK2 but not ROCK1 plays a role in allergen-induced goblet cell hyperplasia.This article is protected by copyright. All rights reserved.
No preview · Article · Oct 2014 · Clinical & Experimental Allergy
[Show abstract][Hide abstract] ABSTRACT: Stroke is a leading cause of death and serious long-term disability. Ischemic stroke is the major subtype of stroke. Currently, its diagnosis is mainly dependent upon clinical symptoms and neuroimaging techniques. Despite these clinical and imaging modalities, often strokes are not recognized after initial onset. As early intervention of medical or surgical therapy is often associated with improved outcomes, there is an urgent need to improve the speed and accuracy of stroke diagnosis. Stroke is a complex pathophysiological process involving; energy failure, imbalance of ion homeostasis, acidosis, intracellular calcium overload, neuronal excitotoxicity, free radical-mediated lipid oxidation, inflammatory cell infiltration, and glial cell activation. These events ultimately lead to neuronal apoptotic cell death or necrosis. In this review, we have summarized the serum biomarkers according to the pathophysiological processes of stroke, which have been intensively studied in clinical trials of stroke over the past five years, and also used Medline's 'related article' option to identify further articles. We focused on the potential biomarkers pertaining to vascular injury, metabolic changes, oxidative injury, and inflammation, and newly studied biomarkers, and discussed how these biomarkers could be used for the diagnosis or determining the prognosis of stroke.
No preview · Article · Jan 2014 · Expert Review of Neurotherapeutics
[Show abstract][Hide abstract] ABSTRACT: Cardiovascular diseases are associated with chronic activation of Rho-associated kinase. Rho-associated kinase activity is significantly correlated with endothelial function and Framingham risk score. However, there is no information on the prognostic value of Rho-associated kinase activity. We evaluated Rho-associated kinase activity in peripheral leukocytes by Western blot analysis in 633 subjects who underwent health-screening examination at Hiroshima University Hospital. We assessed the associations between Rho-associated kinase activity and first major cardiovascular events (death from cardiovascular causes, myocardial infarction, and stroke), death from cardiovascular causes, acute myocardial infarction, stroke, revascularization (percutaneous coronary intervention, coronary artery bypass grafting), and hospitalization for heart failure. During a median period of 42.0 months (interquartile range, 24.4-56.6 months) of follow-up, 29 subjects died (10 from cardiovascular causes), 2 myocardial infarction, 20 revascularization, 15 stroke, and 17 hospitalization for heart failure. After adjustment for age, sex, cardiovascular risk factors, and other relevant variables, Rho-associated kinase activity remained a strong independent indicator of first major cardiovascular events (hazard ratio, 2.19; 95% confidence interval, 1.35-3.70; P=0.002), death from cardiovascular disease (hazard ratio, 2.57; 95% confidence interval, 1.18-6.60; P=0.002), stroke (hazard ratio, 2.14; 95% confidence interval, 1.24-3.86; P=0.006), and revascularization (hazard ratio, 2.68; 95% confidence interval, 1.60-4.66; P<0.001). Leukocyte Rho-associated kinase activity may be a new biomarker of cardiovascular events. These findings suggest that inhibition of Rho-associated kinase activity may be a therapeutic target for prevention of cardiovascular events.
[Show abstract][Hide abstract] ABSTRACT: Recent animal and human studies have demonstrated the importance of RhoA/Rho-associated kinases (ROCKs) pathway in ischemic stroke (IsST). Whether the genetic variation within ROCKs-associated genes modulates IsST risk remains elusive. The association between 66 tag-SNPs (tSNPs) of 3 ROCKs-associated genes (ROCK1, ROCK2 and ARHGEF10) and incident IsST was investigated in 23,294 Caucasian female participants of the prospective Women's Genome Health Study. All were free of known cancer and cardiovascular disease at baseline. During a 15-year follow-up period, 323 participants developed a first ever IsST. Multivariable Cox regression analysis was performed to investigate the relationship between genotypes and IsST risk assuming an additive genetic model. Haplotype-block analysis was also performed. A total of ten tSNPs were associated with IsST risk (three in ARHGEF10, and seven in ROCK1; all p<0.050). Further investigation using the haplotype-block analysis revealed similar significant association of pre-specified haplotypes of ROCK1 with IsST risk (p=0.005). If corroborated in other large prospective studies, the present findings suggest that genetic variation within the ROCKs-associated pathway gene loci examined, in particular, the ROCK1 gene variation may influence IsST risk.
No preview · Article · Dec 2013 · Clinical Science
[Show abstract][Hide abstract] ABSTRACT: Significance:
The 3-hydroxy-methylglutaryl coenzyme A reductase inhibitors or statins are important therapeutic agents for lowering serum cholesterol levels. However, recent studies suggest that statins may exert atheroprotective effects beyond cholesterol lowering. These so-called "pleiotropic effects" include effects of statins on vascular and inflammatory cells. Thus, it is important to understand whether other signaling pathways that are involved in atherosclerosis could be targets of statins, and if so, whether individuals with "overactivity" of these pathways could benefit from statin therapy, regardless of serum cholesterol level.
Statins inhibit the synthesis of isoprenoids, which are important for the function of the Rho/Rho-associated coiled-coil containing kinase (ROCK) pathway. Indeed, recent studies suggest that inhibition of the Rho/ROCK pathway by statins could lead to improved endothelial function and decreased vascular inflammation and atherosclerosis. Thus, the Rho/ROCK pathway has emerged as an important target of statin therapy for reducing atherosclerosis and possibly cardiovascular disease.
Because atherosclerosis is both a lipid and an inflammatory disease, it is important to understand how inhibition of Rho/ROCK pathway could contribute to statins' antiatherosclerotic effects.
The role of ROCKs (ROCK1 and ROCK2) in endothelial, smooth muscle, and inflammatory cells needs to be determined in the context of atherogenesis. This could lead to the development of specific ROCK1 or ROCK2 inhibitors, which could have greater therapeutic benefits with less toxicity. Also, clinical trials will need to be performed to determine whether inhibition of ROCKs, with and without statins, could lead to further reduction in atherosclerosis and cardiovascular disease.
No preview · Article · Aug 2013 · Antioxidants & Redox Signaling
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Recent evidence suggests that Rho-kinase (ROCK) plays an important role in the pathogenesis of atherosclerosis and a marker of atherosclerotic burden. Polyvascular disease with concomitant peripheral arterial disease (PAD) and coronary artery disease (CAD) is common and associated with a worse prognosis. The aim of this study was to evaluate ROCK activity as a marker of polyvascular disease. HYPOTHESIS: METHODS: We retrospectively analyzed patients undergoing coronary angiography at our institution between February 2009 and May 2009. Patients with only CAD (n = 40) defined by coronary artery stenosis of ≥50% by angiography, only PAD (n = 40) defined by an ankle brachial index (ABI) <0.9, and combined CAD/PAD (n = 40) were matched by age and sex to control patients (n = 40) without CAD or PAD. ROCK activity was determined by phosphorylation of the myosin binding subunit in leukocytes and then compared between each group. Multivariate analysis was used to determine independent predictors of polyvascular disease. Discriminative ability of elevated ROCK activity was assessed using receiver operator characteristics (ROC) curves. RESULTS: Patients (age 68 ± 12 years, 79% male) with CAD, PAD, and CAD/PAD had a mean ABI of 1.08, 0.62, and 0.65, respectively, compared to 1.08 in the control group. There was an incremental increase in ROCK activity in patients with CAD (4.61 ± 2.11), PAD (4.27 ± 1.39), and CAD/PAD (5.96 ± 1.94) compared to control (2.40 ± 0.43) (all P < 0.05). ROCK activity (odds ratio: 4.53, 95% confidence interval: 1.26-6.30) was an independent predictor of polyvascular disease. The ROCK cutoff value of 4.85 had a sensitivity of 72.7% and a specificity of 65.7%, with an area under ROC curve of 0.71 for polyvascular disease. CONCLUSIONS: Patients with concomitant peripheral and coronary arterial disease are associated with increased Rho-kinase activity. Rho-kinase activity may be a potential marker of atherosclerotic burden for patients with polyvascular disease.
Preview · Article · Jun 2013 · Clinical Cardiology