Relative contribution of G-protein-coupled pathways to protease-activated receptor-mediated Akt phosphorylation in platelets

AbstractProtease-activated receptors (PARs) activate Gq and G12/13 pathways, as well as Akt (protein kinase B [PKB/Akt]) in platelets. However, the relative contribution of different G-protein pathways to Akt phosphorylation has not been elucidated. We investigated the contribution of Gq and G12/13 to Gi/Gz-mediated Akt phosphorylation downstream of PAR activation. Selective G12/13 activation failed to cause Akt phosphorylation in human and Gαq-deficient mouse platelets. However, supplementing Gi/Gz signaling to G12/13 caused significant increase in Akt phosphorylation, confirming that G12/13 potentiates Akt phosphorylation. Inhibition of PAR-mediated Akt phosphorylation in the presence of the Gq-selective inhibitor YM-254890 was restored to the normal extent achieved by PAR agonists if supplemented with Gi signaling, indicating that Gq does not have any direct effect on Akt phosphorylation. Selective G12/13 activation resulted in Src kinase activation, and Akt phosphorylation induced by costimulation of G12/13 and Gi/Gz was inhibited by a Src kinase inhibitor but not by a Rho kinase inhibitor. These data demonstrate that G12/13, but not Gq, is essential for thrombin-induced Akt phosphorylation in platelets, whereas Gq indirectly contributes to Akt phosphorylation through Gi stimulation by secreted ADP. G12/13 activation might mediate its potentiating effect through Src activation, and Src kinases play an important role in thrombin-mediated Akt phosphorylation.

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Crucial role of Rho-nuclear factor-κB axis in angiotensin II-induced renal injury

AJP Renal Physiology ◽

10.1152/ajprenal.00520.2006 ◽

2007 ◽

Vol 293 (1) ◽

pp. F100-F109 ◽

Cited By ~ 34

Author(s):

Yuri Ozawa ◽

Hiroyuki Kobori

Keyword(s):

Renal Injury ◽

Kinase Inhibitor ◽

Urinary Albumin Excretion ◽

Rho Kinase ◽

Urinary Albumin ◽

Ang Ii ◽

Kinase Activation ◽

Protein Excretion ◽

Rho Kinase Inhibitor ◽

Tgf Β1

This study was performed to determine the effectiveness of the Rho kinase inhibitor and NF-κB inhibitor in renal injury of ANG II-infused hypertensive rats. Male Sprague-Dawley rats, maintained on a normal diet, received either a sham operation ( n = 7) or continuous ANG II infusion (120 ng/min) subcutaneously via minipumps. The ANG II-infused rats were further subdivided into three subgroups ( n = 7 each) to receive one of the following treatments during the entire period: vehicle, Rho kinase inhibitor (fasudil; 3 mg·kg−1·day−1 ip), or NF-κB inhibitor (parthenolide; 1 mg·kg−1·day−1 ip). After 12 days of ANG II infusion, systolic blood pressure (BP; 208 ± 7 vs. 136 ± 3 mmHg), Rho kinase activity, NF-κB activity, renal ANG II contents (160 ± 25 vs. 84 ± 14 pg/g), monocytic chemotactic protein (MCP) 1 mRNA, interstitial macrophage infiltration, transforming growth factor-β1 (TGF-β1) mRNA, interstitial collagen-positive area, urinary protein excretion (43 ± 6 vs. 11 ± 2 mg/day), and urinary albumin excretion were significantly enhanced compared with the Sham group. While fasudil or parthenolide did not alter systolic BP (222 ± and 190 ± 21, respectively), both treatments completely blocked ANG II-induced enhancement of NF-κB activity, renal ANG II contents (103 ± 11 and 116 ± 21 pg/g, respectively), MCP1 mRNA, interstitial macrophage infiltration, TGF-β1 mRNA, interstitial collagen-positive area, urinary protein excretion (28 ± 6 and 23 ± 3 mg/day, respectively), and urinary albumin excretion. Importantly, parthenolide did not alter ANG II-induced Rho kinase activation although fasudil abolished ANG II-induced Rho kinase activation. These data indicate that the Rho-NF-κB axis plays crucial roles in the development of ANG IIinduced renal injury independently from BP regulation.

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Mechanical Stress Induces Osteopontin via ATP/P2Y1 in Periodontal Cells

Journal of Dental Research ◽

10.1177/154405910808700601 ◽

2008 ◽

Vol 87 (6) ◽

pp. 564-568 ◽

Cited By ~ 38

Author(s):

S. Wongkhantee ◽

T. Yongchaitrakul ◽

P. Pavasant

Keyword(s):

Mechanical Stress ◽

Alveolar Bone ◽

Kinase Inhibitor ◽

Inductive Effect ◽

Rho Kinase ◽

Chain Reaction ◽

Kinase Activation ◽

Rho Kinase Inhibitor ◽

Polymerase Chain ◽

Kinase Pathway

Our previous study showed that mechanical stress induced the expression of osteopontin (OPN) in human periodontal ligament (HPDL) cells through the Rho kinase pathway. The increase of OPN expression via Rho kinase has been demonstrated to be triggered by nucleotide. Therefore, we hypothesized that nucleotides, particularly adenosine triphosphate (ATP), participated in the stress-induced OPN expression in HPDL cells. In the present study, the roles of ATP and P2Y1 purinoceptor were examined. Reverse-transcription polymerase chain-reaction and Western blot analysis revealed that the stress-induced ATP exerted its stimulatory effect on OPN expression. The inductive effect was attenuated by apyrase and completely inhibited by the Rho kinase inhibitor, as well as by the P2Y1 antagonist. We here propose that stress induces release of ATP, which in turn mediates Rho kinase activation through the P2Y1 receptor, resulting in the up-regulation of OPN. Stress-induced ATP could play a significant role in alveolar bone resorption.

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Mechanism of RhoA/Rho kinase activation in endothelin-1- induced contraction in rabbit basilar artery

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00141.2002 ◽

2002 ◽

Vol 283 (3) ◽

pp. H983-H989 ◽

Cited By ~ 58

Author(s):

Liyan Miao ◽

Yun Dai ◽

John Zhang

Keyword(s):

Tyrosine Kinase ◽

Basilar Artery ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Kinase Activation ◽

Rhoa Activity ◽

Rhoa Activation ◽

Rho Kinase Inhibitor ◽

Mlc Phosphorylation

This study was undertaken to demonstrate the role of the RhoA/Rho kinase pathway in endothelin-1 (ET-1)-induced contraction of the rabbit basilar artery. Isometric tension and Western blot were used to examine ET-1-induced contraction and RhoA activation. The upstream effect on ET-1-induced RhoA activity was determined by using ETA and ETB receptor antagonists, protein kinase C (PKC), tyrosine kinase, and phosphatidylinositol-3 kinase inhibitors. The downstream effect of ET-1-induced contraction and RhoA activity was studied in the presence of the Rho kinase inhibitor Y-27632. The effect of Rho kinase inhibitor on ET-1-induced myosin light chain (MLC) phosphorylation was investigated by using urea-glycerol-PAGE immunoblotting. We found 1) ET-1 increased RhoA activity (membrane binding RhoA) in a concentration-dependent manner; 2) ETA, but not ETB, receptor antagonist abolished the effect of ET-1 on RhoA activation; 3) phosphodylinositol-3 kinase inhibitor, but not PKC and tyrosine kinase inhibitors, reduced ET-1-induced RhoA activation; 4) Rho kinase inhibitor Y-27632 (10 μM) inhibited ET-1-induced contraction; and 5) ET-1 increased the level of MLC phosphorylation. Rho kinase inhibitor Y-27632 reduced the effect of ET-1 on MLC phosphorylation. This study demonstrated that RhoA/Rho kinase activation is involved in ET-1-induced contraction in the rabbit basilar artery. Phosphodylinositol-3 kinase and MLC might be the upstream and downstream factors of RhoA activation.

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1444: Functional Effect of the Novel Rho-Kinase Inhibitor H-1152 in the Erectile Machinery

The Journal of Urology ◽

10.1016/s0022-5347(18)38669-5 ◽

2004 ◽

Vol 171 (4S) ◽

pp. 380-380

Author(s):

Cleber E. Teixeira ◽

R. Clinton Webb

Keyword(s):

Kinase Inhibitor ◽

Rho Kinase ◽

The Novel ◽

Functional Effect ◽

Rho Kinase Inhibitor

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Faculty Opinions recommendation of Effect of the rho-kinase inhibitor hydroxyfasudil on bladder overactivity: an experimental rat model.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1205957.671055 ◽

2009 ◽

Author(s):

Rodolfo Testa

Keyword(s):

Rat Model ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Rho Kinase Inhibitor ◽

Experimental Rat Model

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Pleiotropic Effects of the Rho-kinase Inhibitor Fasudil After Subarachnoid Hemorrhage: A Review of Preclinical and Clinical Studies

Current Vascular Pharmacology ◽

10.2174/1570161112666140613115813 ◽

2014 ◽

Vol 12 (5) ◽

pp. 758-765 ◽

Cited By ~ 21

Author(s):

Shin-ichi Satoh ◽

Ichiro Ikegaki ◽

Koh Kawasaki ◽

Toshio Asano ◽

Masato Shibuya

Keyword(s):

Subarachnoid Hemorrhage ◽

Clinical Studies ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Pleiotropic Effects ◽

Rho Kinase Inhibitor ◽

Preclinical And Clinical Studies

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A Rho kinase inhibitor (Fasudil) suppresses TGF-β mediated autophagy in urethra fibroblasts to attenuate traumatic urethral stricture (TUS) through re-activating Akt/mTOR pathway: An in vitro study

Life Sciences ◽

10.1016/j.lfs.2020.118960 ◽

2021 ◽

Vol 267 ◽

pp. 118960

Author(s):

Huan Feng ◽

Xiaobing Huang ◽

Weihua Fu ◽

Xingyou Dong ◽

Fengxia Yang ◽

...

Keyword(s):

Urethral Stricture ◽

Kinase Inhibitor ◽

Rho Kinase ◽

In Vitro Study ◽

Mtor Pathway ◽

Vitro Study ◽

Rho Kinase Inhibitor

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Rho-kinase inhibitor hydroxyfasudil protects against HIV-1 Tat-induced dysfunction of tight junction and neprilysin/Aβ transfer receptor expression in mouse brain microvessels

Molecular and Cellular Biochemistry ◽

10.1007/s11010-021-04056-x ◽

2021 ◽

Vol 476 (5) ◽

pp. 2159-2170

Author(s):

Qiangtang Chen ◽

Yu Wu ◽

Yachun Yu ◽

Junxiang Wei ◽

Wen Huang

Keyword(s):

Tight Junction ◽

Signaling Pathway ◽

Mouse Brain ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Receptor Expression ◽

Mrna Levels ◽

Brain Microvessels ◽

Rho Kinase Inhibitor ◽

Hiv 1

AbstractHIV-1 transactivator protein (Tat) induces tight junction (TJ) dysfunction and amyloid-beta (Aβ) clearance dysfunction, contributing to the development and progression of HIV-1-associated neurocognitive disorder (HAND). The Rho/ROCK signaling pathway has protective effects on neurodegenerative disease. However, the underlying mechanisms of whether Rho/ROCK protects against HIV-1 Tat-caused dysfunction of TJ and neprilysin (NEP)/Aβ transfer receptor expression have not been elucidated. C57BL/6 mice were administered sterile saline (i.p., 100 μL) or Rho-kinase inhibitor hydroxyfasudil (HF) (i.p., 10 mg/kg) or HIV-1 Tat (i.v., 100 μg/kg) or HF 30 min before being exposed to HIV-1 Tat once a day for seven consecutive days. Evans Blue (EB) leakage was detected via spectrophotometer and brain slides in mouse brains. The protein and mRNA levels of zonula occludens-1 (ZO-1), occludin, NEP, receptor for advanced glycation end products (RAGE), and low-density lipoprotein receptor-related protein 1 (LRP1) in mouse brain microvessels were, respectively, analyzed by Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) analyses. Exposure of the mice to HIV-1 Tat increased the amount of EB leakage, EB fluorescence intensity, blood–brain barrier (BBB) permeability, as well as the RAGE protein and mRNA levels, and decreased the protein and mRNA levels of ZO-1, occludin, NEP, and LRP1 in mouse brain microvessels. However, these effects were weakened by Rho-kinase inhibitor HF. Taken together, these results provide information that the Rho/ROCK signaling pathway is involved in HIV-1 Tat-induced dysfunction of TJ and NEP/Aβ transfer receptor expression in the C57BL/6 mouse brain. These findings shed some light on potentiality of inhibiting Rho/Rock signaling pathway in handling HAND.

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