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

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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Animal model for angiotensin II effects in the internal anal sphincter smooth muscle: mechanism of action

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00207.2001 ◽

2002 ◽

Vol 282 (3) ◽

pp. G461-G469 ◽

Cited By ~ 13

Author(s):

Ya-Ping Fan ◽

Rajinder N. Puri ◽

Satish Rattan

Keyword(s):

Smooth Muscle ◽

Protein Kinase ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Ang Ii ◽

Kinase C ◽

Rho Kinase Inhibitor ◽

Isolated Smooth Muscle Cells

Effect of ANG II was investigated in in vitro smooth muscle strips and in isolated smooth muscle cells (SMC). Among different species, rat internal and sphincter (IAS) smooth muscle showed significant and reproducible contraction that remained unmodified by different neurohumoral inhibitors. The AT1antagonist losartan but not AT2 antagonist PD-123319 antagonized ANG II-induced contraction of the IAS smooth muscle and SMC. ANG II-induced contraction of rat IAS smooth muscle and SMC was attenuated by tyrosine kinase inhibitors genistein and tyrphostin, protein kinase C (PKC) inhibitor H-7, Ca2+ channel blocker nicardipine, Rho kinase inhibitor Y-27632 or p44/42mitogen-activating protein kinase (MAPK44/42) inhibitor PD-98059. Combinations of nicardipine and H-7, Y-27632, and PD-98059 caused further attenuation of the ANG II effects. Western blot analyses revealed the presence of both AT1 and AT2receptors. We conclude that ANG II causes contraction of rat IAS smooth muscle by the activation of AT1 receptors at the SMC and involves multiple intracellular pathways, influx of Ca2+, and activation of PKC, Rho kinase, and MAPK44/42.

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The absence of sympathoexcitation during the development of hypertension in Cyp1a1 Ren-2 transgenic rats

Physiological Research ◽

10.33549/physiolres.934151 ◽

2019 ◽

pp. 329-334

Author(s):

J. Zicha ◽

J. Hojná ◽

L. Kopkan ◽

L. Červenka ◽

I. Vaněčková

Keyword(s):

Blood Pressure ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Renin Angiotensin System ◽

Ang Ii ◽

Transgenic Rats ◽

Calcium Sensitization ◽

Sympathetic Vasoconstriction ◽

Rho Kinase Inhibitor ◽

Dependent Form

The insertion of mouse renin gene (Ren-2) into the genome of normotensive rats causes a spontaneous rise of blood pressure (BP), leading to an angiotensin II (Ang II)-dependent form of hypertension in transgenic (mRen-2)27 rats (TGR). However, enhanced sympathetic BP component was demonstrated in heterozygous TGR aged 20 weeks. In the present study we used another model, i.e. Cyp1a1-Ren-2 transgenic rats (iTGR) in which hypertension can be induced by natural xenobiotic indole-3 carbinol (I3C) added to the diet. We investigated whether the development of high blood pressure (BP) in 5-month-old iTGR animals fed I3C diet for 10 days is solely due to enhanced Ang II-dependent vasoconstriction or whether enhanced sympathetic vasoconstriction also participates in BP maintenance in this form of hypertension. Using acute sequential blockade of renin-angiotensin system (RAS), sympathetic nervous system (SNS) and NO synthase (NOS) we have demonstrated that the observed gradual increase of BP in iTGR fed I3C diet was entirely due to the augmentation of Ang II-dependent BP component without significant changes of sympathetic BP component. Thus, the hypertension in iTGR resembles to that of homozygous TGR in which high BP was entirely dependent on Ang II-dependent vasoconstriction. Moreover, our measurements of acute BP response to Rho kinase inhibitor fasudil in animals subjected to a combined blockade of RAS, SNS and NOS indicated the attenuation of basal calcium sensitization in both iTGR and homozygous TGR.

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Sex differences in the enhanced responsiveness to acute angiotensin II in growth-restricted rats: role of fasudil, a Rho kinase inhibitor

AJP Renal Physiology ◽

10.1152/ajprenal.00687.2012 ◽

2013 ◽

Vol 304 (7) ◽

pp. F900-F907 ◽

Cited By ~ 14

Author(s):

Norma B. Ojeda ◽

Thomas P. Royals ◽

Barbara T. Alexander

Keyword(s):

Blood Pressure ◽

Glomerular Filtration Rate ◽

Angiotensin Ii ◽

Glomerular Filtration ◽

Filtration Rate ◽

Kinase Inhibitor ◽

Rho Kinase ◽

Ang Ii ◽

Intact Male ◽

Rho Kinase Inhibitor

This study tested the hypothesis that Rho kinase contributes to the enhanced pressor response to acute angiotensin II in intact male growth-restricted and gonadectomized female growth-restricted rats. Mean arterial pressure (MAP) and renal function were determined in conscious animals pretreated with enalapril (250 mg/l in drinking water) for 1 wk to block the endogenous renin-angiotensin system and normalize blood pressure (baseline). Blood pressure and renal hemodynamics did not differ at baseline. Acute Ang II (100 ng·kg−1·min−1) induced a greater increase in MAP and renal vascular resistance and enhanced reduction in glomerular filtration rate in intact male growth-restricted rats compared with intact male controls ( P < 0.05). Cotreatment with the Rho kinase inhibitor fasudil (33 μg·kg−1·min−1) significantly attenuated these hemodynamic changes ( P < 0.05), but it did not abolish the differential increase in blood pressure above baseline, suggesting that the impact of intrauterine growth restriction on blood pressure in intact male growth-restricted rats is independent of Rho kinase. Gonadectomy in conjunction with fasudil returned blood pressure back to baseline in male growth-restricted rats, and yet glomerular filtration rate remained significantly reduced ( P < 0.05). Thus, these data suggest a role for enhanced renal sensitivity to acute Ang II in the developmental programming of hypertension in male growth-restricted rats. However, inhibition of Rho kinase had no effect on the basal or enhanced increase in blood pressure induced by acute Ang II in the gonadectomized female growth-restricted rat. Therefore, these studies suggest that Rho kinase inhibition exerts a sex-specific effect on blood pressure sensitivity to acute Ang II in growth-restricted rats.

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

Blood ◽

10.1182/blood-2005-07-3040 ◽

2006 ◽

Vol 107 (3) ◽

pp. 947-954 ◽

Cited By ~ 59

Author(s):

Soochong Kim ◽

Jianguo Jin ◽

Satya P. Kunapuli

Keyword(s):

G Protein ◽

Kinase Inhibitor ◽

Src Kinase ◽

Rho Kinase ◽

Protease Activated Receptors ◽

Kinase Activation ◽

Akt Phosphorylation ◽

Relative Contribution ◽

Rho Kinase Inhibitor ◽

G Protein Coupled

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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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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