Abstract 533: Crucial Role of Rho-Kinase in Pressure Overload--Induced Right Ventricular Hypertrophy and Dysfunction in Mice: A Possible Novel Therapeutic Target of Right Ventricular Failure

Rationale: Right ventricular (RV) failure is the leading cause of death in various cardiopulmonary diseases, including pulmonary hypertension. It is generally considered that the RV is vulnerable to pressure-overload as compared with the left ventricle (LV). However, as compared with LV failure, the molecular mechanisms of RV failure are poorly understood. Objective: We aimed to identify molecular therapeutic targets for RV failure in a mouse model of pressure-overload. Methods and Results: To induce pressure-overload to respective ventricles, we performed pulmonary artery constriction (PAC) or transverse aortic constriction (TAC) in mice. We first performed microarray analysis and found that the molecules related to RhoA/Rho-kinase and integrin pathways were significantly up-regulated in the RV with PAC compared with the LV with TAC. Then, we examined the responses of both ventricles to chronic pressure-overload in vivo. We demonstrated that compared with TAC, PAC caused greater extents of mortality, Rho-kinase expression (especially ROCK2 isoform) and oxidative stress in pressure-overloaded RV, reflecting the weakness of the RV in response to pressure-overload. Additionally, mechanical stretch of RV cardiomyocytes from rats immediately up-regulated ROCK2 expression (not ROCK1), suggesting the specific importance of ROCK2 in stretch-induced responses of RV tissues. Furthermore, mice with myocardial-specific overexpression of dominant-negative Rho-kinase (DN-RhoK) showed resistance to pressure-overload-induced hypertrophy and dysfunction associated with reduced oxidative stress. Finally, DN-RhoK mice showed a significantly improved long-term survival in both PAC and TAC as compared with littermate controls. Conclusions: These results indicate that the Rho-kinase pathway plays a crucial role in RV hypertrophy and dysfunction, suggesting that the pathway is a novel therapeutic target of RV failure in humans.

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Crucial Role of Rho-kinase in Pressure-overload-induced Right Ventricular Hypertrophy and Dysfunction in Mice

Journal of Cardiac Failure ◽

10.1016/j.cardfail.2014.07.085 ◽

2014 ◽

Vol 20 (10) ◽

pp. S144

Author(s):

Shohei Ikeda ◽

Kimio Satoh ◽

Nobuhiro Kikuchi ◽

Satoshi Miyata ◽

Kota Suzuki ◽

...

Keyword(s):

Right Ventricular ◽

Crucial Role ◽

Ventricular Hypertrophy ◽

Rho Kinase ◽

Pressure Overload ◽

Right Ventricular Hypertrophy

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Crucial Role of Rho-Kinase in Pressure Overload–Induced Right Ventricular Hypertrophy and Dysfunction in Mice

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvbaha.114.303320 ◽

2014 ◽

Vol 34 (6) ◽

pp. 1260-1271 ◽

Cited By ~ 44

Author(s):

Shohei Ikeda ◽

Kimio Satoh ◽

Nobuhiro Kikuchi ◽

Satoshi Miyata ◽

Kota Suzuki ◽

...

Keyword(s):

Right Ventricular ◽

Crucial Role ◽

Ventricular Hypertrophy ◽

Rho Kinase ◽

Pressure Overload ◽

Right Ventricular Hypertrophy

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Effects of Tolvaptan on Oxidative Stress in ADPKD: A Molecular Biological Approach

Journal of Clinical Medicine ◽

10.3390/jcm11020402 ◽

2022 ◽

Vol 11 (2) ◽

pp. 402

Author(s):

Matteo Rigato ◽

Gianni Carraro ◽

Irene Cirella ◽

Silvia Dian ◽

Valentina Di Di Vico ◽

...

Keyword(s):

Oxidative Stress ◽

Protein Expression ◽

Molecular Mechanisms ◽

Kinase Activity ◽

Rho Kinase ◽

Renal Deterioration ◽

Deterioration Rate ◽

Function Loss ◽

State Marker ◽

Molecular Biological Approach

Autosomal dominant polycystic disease (ADPKD) is the most frequent monogenic kidney disease. It causes progressive renal failure, endothelial dysfunction, and hypertension, all of which are strictly linked to oxidative stress (OxSt). Treatment with tolvaptan is known to slow the renal deterioration rate, but not all the molecular mechanisms involved in this effect are well-established. We evaluated the OxSt state in untreated ADPKD patients compared to that in tolvaptan-treated ADPKD patients and healthy subjects. OxSt was assessed in nine patients for each group in terms of mononuclear cell p22phox protein expression, NADPH oxidase key subunit, MYPT-1 phosphorylation state, marker of Rho kinase activity (Western blot) and heme oxygenase (HO)-1, induced and protective against OxSt (ELISA). p22phox protein expression was higher in untreated ADPKD patients compared to treated patients and controls: 1.42 ± 0.11 vs. 0.86 ± 0.15 d.u., p = 0.015, vs. 0.53 ± 0.11 d.u., p < 0.001, respectively. The same was observed for phosphorylated MYPT-1: 0.96 ± 0.28 vs. 0.68 ± 0.09 d.u., p = 0.013 and vs. 0.47 ± 0.13 d.u., p < 0.001, respectively, while the HO-1 expression of untreated patients was significantly lower compared to that of treated patients and controls: 5.33 ± 3.34 vs. 2.08 ± 0.79 ng/mL, p = 0.012, vs. 1.97 ± 1.22 ng/mL, p = 0.012, respectively. Tolvaptan-treated ADPKD patients have reduced OxSt levels compared to untreated patients. This effect may contribute to the slowing of renal function loss observed with tolvaptan treatment.

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M-005 CARDIOPROTECTIVE MECHANISMS OF RHO-KINASE INHIBITION VIA ANTI-OXIDATIVE STRESS IN PRESSURE OVERLOAD HEART IN RATS

Journal of Hypertension ◽

10.1097/01.hjh.0000408094.84086.4c ◽

2011 ◽

Vol 29 ◽

pp. e39

Author(s):

Zen-Kong Dai ◽

Jiunn-Ren Wu ◽

I-Chen Chen ◽

Jong-Hau Hsu

Keyword(s):

Oxidative Stress ◽

Rho Kinase ◽

Pressure Overload ◽

Kinase Inhibition

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Abstract 080: Eya4 Induces Hypertrophy Via Regulation Of p27kip1

Circulation Research ◽

10.1161/res.113.suppl_1.a080 ◽

2013 ◽

Vol 113 (suppl_1) ◽

Author(s):

Tatjana Williams ◽

Moritz Hundertmark ◽

Peter Nordbeck ◽

Sabine Voll ◽

Melanie Muehlfelder ◽

...

Keyword(s):

Transgenic Mice ◽

Cardiac Hypertrophy ◽

Molecular Mechanisms ◽

Pressure Overload ◽

Dominant Negative ◽

Heart Weight ◽

Dominant Negative Effect ◽

Mutant Form ◽

Cardiac Phenotype ◽

Truncating Mutation

Introduction: E193, a truncating mutation in the transcription cofactor Eyes absent 4 (Eya4) causes hearing impairment followed by heart failure. Here we identified the Eya4 dependent molecular mechanisms leading to the cardiac phenotype in the E193 mutation. Methods and Results: First we showed in vitro that the cyclin-dependent kinase inhibitor protein p27kip1 is a direct target of Eya4/Six1 and is suppressed upon Eya4 overexpression, whereas E193 has a dominant negative effect, releasing Eya4 mediated suppression of p27. We next generated transgenic mice with cardiac specific constitutive overexpression of full-length Eya4 or the mutant form E193. While E193 transgenic mice developed age-dependent DCM, Eya4 mice displayed cardiac hypertrophy already under basal conditions as judged by increases in heart weight and cardiomyocyte cross-sectional areas along with increases in myocardial dimension and mass. These two distinct cardiac phenotypes were even more aggravated upon pressure overload suggesting Eya4 is a regulator of cardiac hypertrophy. We also observed that the activity of Casein Kinase 2-α and the phosphorylation status of HDAC2 were significantly upregulated in the Eya4 transgenic mice, while they were significantly reduced in E193 mice, under baseline conditions and pressure overload. We were also able to identify a new human mutation (E215) with a phenotype comparable to the one seen in E193 patients. Conclusion: Our results implicate that Eya4/Six1 regulates cardiac hypertrophic reactions via p27/CK2-α/HDAC2 and indicate that truncating mutations in Eya4 interfere with this newly established signalling pathway.

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Molecular Interactions of α-Synuclein, Mitochondria, and Cellular Degradation Pathways in Parkinson's Disease

Quality Control of Cellular Protein in Neurodegenerative Disorders - Advances in Medical Diagnosis, Treatment, and Care ◽

10.4018/978-1-7998-1317-0.ch008 ◽

2020 ◽

pp. 212-234

Author(s):

Mansi Verma ◽

Sujata Basu ◽

Manisha Singh ◽

Rachana R. ◽

Simrat Kaur ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Molecular Interactions ◽

Therapeutic Target ◽

Molecular Mechanisms ◽

Degradation Pathways ◽

Functional Changes ◽

The World ◽

Novel Therapeutic

Parkinson's disease (PD) has been reported to be the most common neurodegenerative diseases all over the world. Several proteins are associated and responsible for causing PD. One such protein is α-synuclein. This chapter discusses the role of α-synuclein in PD. Various genetic and epigenetic factors, which cause structural and functional changes for α-synuclein, have been described. Several molecular mechanisms, which are involved in regulating mitochondrial and lysosomal related pathways and are linked to α-synuclein, have been discussed in detail. The knowledge gathered is further discussed in terms of using α-synuclein as a diagnostic marker for PD and as a novel therapeutic target for the same.

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Different roles of myocardial ROCK1 and ROCK2 in cardiac dysfunction and postcapillary pulmonary hypertension in mice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1721298115 ◽

2018 ◽

Vol 115 (30) ◽

pp. E7129-E7138 ◽

Cited By ~ 31

Author(s):

Shinichiro Sunamura ◽

Kimio Satoh ◽

Ryo Kurosawa ◽

Tomohiro Ohtsuki ◽

Nobuhiro Kikuchi ◽

...

Keyword(s):

Oxidative Stress ◽

Pulmonary Hypertension ◽

Cardiac Hypertrophy ◽

Cardiac Dysfunction ◽

High Throughput Screening ◽

Histological Analysis ◽

Rho Kinase ◽

Pressure Overload ◽

Aortic Constriction ◽

Patients With Heart Failure

Although postcapillary pulmonary hypertension (PH) is an important prognostic factor for patients with heart failure (HF), its pathogenesis remains to be fully elucidated. To elucidate the different roles of Rho-kinase isoforms, ROCK1 and ROCK2, in cardiomyocytes in response to chronic pressure overload, we performed transverse aortic constriction (TAC) in cardiac-specific ROCK1-deficient (cROCK1−/−) and ROCK2-deficient (cROCK2−/−) mice. Cardiomyocyte-specific ROCK1 deficiency promoted pressure-overload-induced cardiac dysfunction and postcapillary PH, whereas cardiomyocyte-specific ROCK2 deficiency showed opposite results. Histological analysis showed that pressure-overload-induced cardiac hypertrophy and fibrosis were enhanced in cROCK1−/− mice compared with controls, whereas cardiac hypertrophy was attenuated in cROCK2−/− mice after TAC. Consistently, the levels of oxidative stress were up-regulated in cROCK1−/− hearts and down-regulated in cROCK2−/− hearts compared with controls after TAC. Furthermore, cyclophilin A (CyPA) and basigin (Bsg), both of which augment oxidative stress, enhanced cardiac dysfunction and postcapillary PH in cROCK1−/− mice, whereas their expressions were significantly lower in cROCK2−/− mice. In clinical studies, plasma levels of CyPA were significantly increased in HF patients and were higher in patients with postcapillary PH compared with those without it. Finally, high-throughput screening demonstrated that celastrol, an antioxidant and antiinflammatory agent, reduced the expressions of CyPA and Bsg in the heart and the lung, ameliorating cardiac dysfunction and postcapillary PH induced by TAC. Thus, by differentially affecting CyPA and Bsg expressions, ROCK1 protects and ROCK2 jeopardizes the heart from pressure-overload HF with postcapillary PH, for which celastrol may be a promising agent.

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P4996The adult heart requires baseline expression of the transcription factor Hand2 to withstand right ventricular pressure overload

European Heart Journal ◽

10.1093/eurheartj/ehz746.0174 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

A M C Koop ◽

R F Videira ◽

L Ottaviani ◽

E M Poels ◽

K W Van De Kolk ◽

...

Keyword(s):

Transcription Factor ◽

Right Ventricular ◽

Rna Sequencing ◽

Cardiac Remodeling ◽

Cardiac Dysfunction ◽

Molecular Mechanisms ◽

Pressure Overload ◽

Left Ventricular ◽

Adult Heart ◽

Hypertrophic Growth

Abstract Introduction Heart and neural crest derivatives expressed-2 (Hand2) has been identified as an important embryonic basic helix-loop-helix-transcription factor, with different functions in the development of the first and second heart field, from which the left and right ventricle originate, respectively. Our previous work revealed that Hand2, under conditions of left ventricular (LV) pressure overload, is re-expressed in the adult heart and activates a “fetal gene” program contributing to pathological cardiac remodeling. Ablation of cardiac expression of Hand2 resulted in protection to cardiac stress and attenuated maladaptive remodeling. Purpose In this study, we aimed at unraveling the role of Hand2 during cardiac remodeling in response to right ventricular (RV) pressure overload induced by pulmonary artery banding (PAB). Methods Hand2F/F and MCM− Hand2F/F mice were treated with tamoxifen (control and knockout, respectively) and subjected to six weeks of RV pressure overload induced by PAB. Echocardiographic and MRI derived hemodynamic parameters, and molecular remodelling were assessed for experimental groups and compared to sham-operated controls (Fig. 1a). RNA sequencing and gene ontology enrichment analysis were performed to compare the dysregulated genes between the pressure overloaded RV of the control and Hand2 knockout mice. Results After six weeks of increased pressure load (Fig. 1b), levels of Hand2 increased in the control banded animals but, as expected, remained absent in the knockout hearts (Fig. 1c). In contrast to the what was previously observed for the pressure overloaded LV, in the pressure loaded RV, Hand2 depletion resulted in more severe remodelling and dysfunction as reflected by increased hypertrophic growth, increased RV end-diastolic and end-systolic volumes as well as decreased RV ejection fraction (Fig. 1d–g). In addition, RNA sequencing revealed a distinct set of genes that are dysregulated in the pressure-overloaded RV, compared to the previously described pressure-overloaded LV. These include components of the extracellular matrix structure, collagen assembly and organization and several types of collagens. Genes associated with inflammation response, adhesion and muscle organization were also affected in the RV of the Hand2 KO mice (Fig. 1h). Figure 1 Conclusion Cardiac-specific depletion of Hand2 is associated with severe cardiac dysfunction in conditions of RV pressure overload. While inhibiting Hand2 expression can prevent cardiac dysfunction in conditions of LV pressure overload, the same does not hold true for conditions of RV pressure overload. This study highlights the need to better understand the molecular mechanisms driving pathological remodelling of the RV, in contrast to the LV, in order to better diagnose and treat patients with RV or LV failure.

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