scholarly journals Myosin Phosphatase Target Subunit 1 (MYPT1) Regulates the Contraction and Relaxation of Vascular Smooth Muscle and Maintains Blood Pressure

2014 ◽  
Vol 289 (32) ◽  
pp. 22512-22523 ◽  
Author(s):  
Yan-Ning Qiao ◽  
Wei-Qi He ◽  
Cai-Ping Chen ◽  
Cheng-Hai Zhang ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Myosin Phosphatase ◽  
Contraction And Relaxation

scholarly journals Smooth muscle-selective CPI-17 expression increases vascular smooth muscle contraction and blood pressure

2013 ◽  
Vol 305 (1) ◽  
pp. H104-H113 ◽  
Author(s):  
Wen Su ◽  
Zhongwen Xie ◽  
Shu Liu ◽  
Lindsay E. Calderon ◽  
Zhenheng Guo ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Protein Kinase ◽  
Vascular Smooth Muscle ◽  
Mesenteric Arteries ◽  
Myosin Phosphatase ◽  
Inhibitory Protein ◽  
Muscle Contractility ◽  
Smooth Muscle Contractility ◽  
High Potassium

Recent data revealed that protein kinase C-potentiated myosin phosphatase inhibitor of 17 kDa (CPI-17), a myosin phosphatase inhibitory protein preferentially expressed in smooth muscle, is upregulated/activated in several diseases but whether this CPI-17 increase plays a causal role in pathologically enhanced vascular smooth muscle contractility and blood pressure remains unclear. To address this possibility, we generated a smooth muscle-specific CPI-17 transgenic mouse model (CPI-17-Tg) and demonstrated that the CPI-17 transgene was selectively expressed in smooth muscle-enriched tissues, including mesenteric arteries. The isometric contractions in the isolated second-order branch of mesenteric artery helical strips from CPI-17-Tg mice were significantly enhanced compared with controls in response to phenylephrine, U-46619, serotonin, ANG II, high potassium, and calcium. The perfusion pressure increases in isolated perfused mesenteric vascular beds in response to norepinephrine were also enhanced in CPI-17-Tg mice. The hypercontractility was associated with increased phosphorylation of CPI-17 and 20-kDa myosin light chain under basal and stimulated conditions. Surprisingly, the protein levels of rho kinase 2 and protein kinase Cα/δ were significantly increased in CPI-17-Tg mouse mesenteric arteries. Radiotelemetry measurements demonstrated that blood pressure was significantly increased in CPI-17-Tg mice. However, no vascular remodeling was detected by morphometric analysis. Taken together, our results demonstrate that increased CPI-17 expression in smooth muscle promotes vascular smooth muscle contractility and increases blood pressure, implicating a pathological significant role of CPI-17 upregulation.

P4477Editing of myosin phosphatase as a novel approach for sensitization of vascular smooth muscle to vasodilators (NO/cGMP/ROS) and lowering of blood pressure in hypertension

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
S Fisher ◽  
J J Reho ◽  
M Meddeb ◽  
J Ursitti ◽  
M Htet
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
World Wide ◽  
Mesenteric Arteries ◽  
Smooth Muscle Relaxation ◽  
Myosin Phosphatase ◽  
Substantial Impact

Abstract Background Despite the many drugs for treatment of hypertension, it remains inadequately treated in >50% of patients and the number one contributor to cardiovascular mortality world-wide. Thus new targets and treatment strategies are badly needed. Myosin Phosphatase (MP) is a viable target: it is the primary effector of vascular smooth muscle relaxation and a critical mediator of signaling pathways regulating vessel tone. Purpose We are using complementary/ translatable approaches to test the hypothesis: editing of the Myosin Phosphatase Regulatory (Targeting) subunit (MYPT1), by shifting the expression of naturally occurring isoforms, will sensitize vascular smooth muscle to NO/cGMP/ROS mediated vasorelaxation and thereby lower BP in models of hypertension. A further goal is to determine mechanisms by which these signals activate MP thereby causing vasorelaxation. Methods LoxP sites were inserted in introns flanking alternative Exon24 (E24) of Mypt1. Mice were crossed with smMHCCreER mice and treated with Tamoxifen for smooth muscle specific deletion of E24 (SMcKO E24).Skipping E24 codes for a Mypt1 isoform that contains a C-terminal leucine zipper (LZ) motif required for cGMP-dependent protein kinase (cGK1) binding and NO/cGMP/ROS activation of MP. Second, we developed and tested guide RNAs for the purpose of AAV-CRISPR/CAS9 editing of Mypt1 E24 as a treatment for hypertension. Effect of editing is tested in otherwise normal mice and in the AngII sub-pressor model of hypertension. Results SMcKO E24 mice had mean BP that was 15+3 mmHg lower than control (n=5; p<0.05). Mesenteric arteries from these mice were significantly more sensitive to DEA/NO mediated relaxation (EC50: 2.1+0.5 nM vs 18.2+5.6 mM; n=5–6, p<0.05). Experiments testing response to AngII infusion are in progress and will be presented at the meeting. Preliminary biochemical assays support a 2-pool model, in which NO/cGMP/ROS activates the LZ+ pool, while contractile agonists inhibit the LZ- pool of MP, in the control of BP/ blood flow. We have generated a number of AAV Crispr/Cas9 gRNAs and validated their efficacy of editing of Mypt1 E24 in vitro. Experiments are in progress to test their efficacy and effect on BP in vivo. Conclusion These studies support that editing of Mypt1 E24 could be a novel strategy for vasodilator sensitization and effective lowering of blood pressure in humans with hypertension, thereby having a substantial impact on CV mortality world-wide. Acknowledgement/Funding NIH

scholarly journals RGS5 Attenuates Baseline Activity of ERK1/2 and Promotes Growth Arrest of Vascular Smooth Muscle Cells

Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1748
Author(s):  
Eda Demirel ◽  
Caroline Arnold ◽  
Jaspal Garg ◽  
Marius Andreas Jäger ◽  
Carsten Sticht ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Map Kinase ◽  
Vascular Smooth Muscle Cells ◽  
Muscle Cells ◽  
Genetic Ablation ◽  
Variable Expression ◽  
Arterial Blood

The regulator of G-protein signaling 5 (RGS5) acts as an inhibitor of Gαq/11 and Gαi/o activity in vascular smooth muscle cells (VSMCs), which regulate arterial tone and blood pressure. While RGS5 has been described as a crucial determinant regulating the VSMC responses during various vascular remodeling processes, its regulatory features in resting VSMCs and its impact on their phenotype are still under debate and were subject of this study. While Rgs5 shows a variable expression in mouse arteries, neither global nor SMC-specific genetic ablation of Rgs5 affected the baseline blood pressure yet elevated the phosphorylation level of the MAP kinase ERK1/2. Comparable results were obtained with 3D cultured resting VSMCs. In contrast, overexpression of RGS5 in 2D-cultured proliferating VSMCs promoted their resting state as evidenced by microarray-based expression profiling and attenuated the activity of Akt- and MAP kinase-related signaling cascades. Moreover, RGS5 overexpression attenuated ERK1/2 phosphorylation, VSMC proliferation, and migration, which was mimicked by selectively inhibiting Gαi/o but not Gαq/11 activity. Collectively, the heterogeneous expression of Rgs5 suggests arterial blood vessel type-specific functions in mouse VSMCs. This comprises inhibition of acute agonist-induced Gαq/11/calcium release as well as the support of a resting VSMC phenotype with low ERK1/2 activity by suppressing the activity of Gαi/o.

Myosin phosphatase isoform switching in vascular smooth muscle development

2006 ◽  
Vol 40 (2) ◽  
pp. 274-282 ◽  
Author(s):  
M PAYNE ◽  
H ZHANG ◽  
T PROSDOCIMO ◽  
K JOYCE ◽  
Y KOGA ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Muscle Development ◽  
Myosin Phosphatase ◽  
Isoform Switching

Abstract P501: Editing of Myosin Phosphatase Gene as a Novel Approach for Vasodilator Sensitization and Lowering of Blood Pressure

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Mariam Meddeb ◽  
Jeanine Ursitti ◽  
John Reho ◽  
Steven A Fisher
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Leucine Zipper ◽  
Splice Variants ◽  
Species Conservation ◽  
Mesenteric Arteries ◽  
Hek293 Cells ◽  
Myosin Phosphatase ◽  
Novel Approach

Myosin Phosphatase (MP) is the primary effector of vascular smooth muscle (VSM) relaxation and a key end target of signaling pathways that regulate vessel tone. Regulated splicing of alternative Exon24 (E24) of Myosin Phosphatase Regulatory/ Targeting subunit (MYPT1) sets vasodilator sensitivity. Skipping E24 codes for a Mypt1 isoform that contains a C-terminal leucine zipper (LZ) motif required for cGK1α binding and NO/cGMP activation of MP resulting in vasodilation. Inclusion of 31 nt E24 shifts the reading frame coding for a Mypt1 isoform with a distinct C-terminus (LZ-) that is unresponsive to NO/cGMP. We are using two editing approaches to test the function of Mypt1 E24 splice variants in the control of BP in vivo. First, LoxP sites were inserted in introns flanking E24, crossed with smMHCCre ER , and treated with Tamoxifen to achieve smooth muscle-specific cKO of E24 (SMcKO E24), thereby converting Mypt1 to the LZ+ isoform. E24 cKO mice had mean BP that was 15 + 3 mmHg lower than control (n=3-5; p<0.05). Mesenteric arteries from these mice were significantly more sensitive to DEA/NO mediated relaxation (EC 50 : 2.1+0.5 nM vs 18.2+5.6 μM; n=5-6, p<0.05). We now are developing CRISPR/CAS9 editing of Mypt1 for translation into humans with hypertension. Guide(g)RNAs targeting E24 were designed using Benchling.com and selected for further study based on predicted efficacy, specificity (>10%,>60%) and cross-species conservation. Plasmids were generated by sub-cloning of oligonucleotides into the parent pX601 plasmid for the purpose of co-expression of gRNA and saCas9. These plasmids were transfected into HEK293 cells singly and in combinations and Mypt1 gene editing assayed by PCR, Surveyor nuclease assays and sequencing of genomic DNA. Single gRNAs yielded deletions of 1-3 nt. Combinations yielded deletions of 104-334 nt that removed >80% of E24 with an efficiency of editing that varied from 10% (gRNAs 6+9 and 5+9) to 40% (gRNAs 6+11 and 5+11). We have now generated AAVgE24 and are testing their efficiency of editing of VSM in vivo. These studies support that AAV mediated CRISPR/Cas9 editing of Mypt1 E24 could be a novel strategy for vasodilator sensitization and effective lowering of blood pressure in humans.

scholarly journals Angiotensin II, Hypercholesterolemia, and Vascular Smooth Muscle Cells: A Perfect Trio for Vascular Pathology

2020 ◽  
Vol 21 (12) ◽  
pp. 4525
Author(s):  
Amanda St. Paul ◽  
Cali B. Corbett ◽  
Rachael Okune ◽  
Michael V. Autieri
Keyword(s):  
Blood Pressure ◽  
Cardiovascular Disease ◽  
Smooth Muscle ◽  
Angiotensin Ii ◽  
Vascular Smooth Muscle ◽  
Vascular Diseases ◽  
Reduce Blood Pressure ◽  
Vascular Pathology ◽  
Lipid Lowering ◽  
Ang Ii

Cardiovascular disease is the leading cause of morbidity and mortality in the Western and developing world, and the incidence of cardiovascular disease is increasing with the longer lifespan afforded by our modern lifestyle. Vascular diseases including coronary heart disease, high blood pressure, and stroke comprise the majority of cardiovascular diseases, and therefore represent a significant medical and socioeconomic burden on our society. It may not be surprising that these conditions overlap and potentiate each other when we consider the many cellular and molecular similarities between them. These intersecting points are manifested in clinical studies in which lipid lowering therapies reduce blood pressure, and anti-hypertensive medications reduce atherosclerotic plaque. At the molecular level, the vascular smooth muscle cell (VSMC) is the target, integrator, and effector cell of both atherogenic and the major effector protein of the hypertensive signal Angiotensin II (Ang II). Together, these signals can potentiate each other and prime the artery and exacerbate hypertension and atherosclerosis. Therefore, VSMCs are the fulcrum in progression of these diseases and, therefore, understanding the effects of atherogenic stimuli and Ang II on the VSMC is key to understanding and treating atherosclerosis and hypertension. In this review, we will examine studies in which hypertension and atherosclerosis intersect on the VSMC, and illustrate common pathways between these two diseases and vascular aging.

scholarly journals Estrogen and testosterone in concert with EFNB3 regulate vascular smooth muscle cell contractility and blood pressure

2016 ◽  
Vol 310 (7) ◽  
pp. H861-H872 ◽  
Author(s):  
Yujia Wang ◽  
Zenghui Wu ◽  
Eric Thorin ◽  
Johanne Tremblay ◽  
Julie L. Lavoie ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Gene Knockout ◽  
Target Cells ◽  
Wild Type ◽  
Cell Contractility ◽  
Risk Gene ◽  
Kinase Phosphorylation

EPH kinases and their ligands, ephrins (EFNs), have vital and diverse biological functions, although their function in blood pressure (BP) control has not been studied in detail. In the present study, we report that Efnb3 gene knockout (KO) led to increased BP in female but not male mice. Vascular smooth muscle cells (VSMCs) were target cells for EFNB3 function in BP regulation. The deletion of EFNB3 augmented contractility of VSMCs from female but not male KO mice, compared with their wild-type (WT) counterparts. Estrogen augmented VSMC contractility while testosterone reduced it in the absence of EFNB3, although these sex hormones had no effect on the contractility of VSMCs from WT mice. The effect of estrogen on KO VSMC contractility was via a nongenomic pathway involving GPER, while that of testosterone was likely via a genomic pathway, according to VSMC contractility assays and GPER knockdown assays. The sex hormone-dependent contraction phenotypes in KO VSMCs were reflected in BP in vivo. Ovariectomy rendered female KO mice normotensive. At the molecular level, EFNB3 KO in VSMCs resulted in reduced myosin light chain kinase phosphorylation, an event enhancing sensitivity to Ca2+ flux in VSMCs. Our investigation has revealed previously unknown EFNB3 functions in BP regulation and show that EFNB3 might be a hypertension risk gene in certain individuals.

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