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Guo Q, Chen G, Cheng H, Qing Y, Truong L, Ma Q, Wang Y, Cheng J. Temporal regulation of notch activation improves arteriovenous fistula maturation. J Transl Med 2022; 20:543. [PMID: 36419038 PMCID: PMC9682688 DOI: 10.1186/s12967-022-03727-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 10/23/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Arteriovenous fistula (AVF) maturation is a process involving remodeling of venous arm of the AVFs. It is a challenge to balance adaptive AVF remodeling and neointima formation. In this study we temporally controlled Notch activation to promote AVF maturation while avoiding neointima formation. METHODS Temporal Notch activation was controlled by regulating the expression of Notch transcription factor, RBP-Jκ, or dnMAML1 (dominant negative MAML2) in vascular smooth muscle cells (VSMCs). AVF mouse model was created and VSMC phenotype dynamic changes during AVF remodeling were determined. RESULTS Activated Notch was found in the nuclei of neointimal VSMCs in AVFs from uremic mice. We found that the VSMCs near the anastomosis became dedifferentiated and activated after AVF creation. These dedifferentiated VSMCs regained smooth muscle contractile markers later during AVF remodeling. However, global or VSMC-specific KO of RBP-Jκ at early stage (before or 1 week after AVF surgery) blocked VSMC differentiation and neointima formation in AVFs. These un-matured AVFs showed less intact endothelium and increased infiltration of inflammatory cells. Consequently, the VSMC fate in the neointima was completely shut down, leading to an un-arterialized AVF. In contrast, KO of RBP-Jκ at late stage (3 weeks after AVF surgery), it could not block neointima formation and vascular stenosis. Inhibition of Notch activation at week 1 or 2, could maintain VSMC contractile markers expression and facilitate AVF maturation. CONCLUSIONS This work uncovers the molecular and cellular events in each segment of AVF remodeling and found that neither sustained increasing nor blocking of Notch signaling improves AVF maturation. It highlights a novel strategy to improve AVF patency: temporally controlled Notch activation can achieve a balance between adaptive AVF remodeling and neointima formation to improve AVF maturation. TRANSLATIONAL PERSPECTIVE Adaptive vascular remodeling is required for AVF maturation. The balance of wall thickening of the vein and neointima formation in AVF determines the fate of AVF function. Sustained activation of Notch signaling in VSMCs promotes neointima formation, while deficiency of Notch signaling at early stage during AVF remodeling prevents VSMC accumulation and differentiation from forming a functional AVFs. These responses also delay EC regeneration and impair EC barrier function with increased inflammation leading to failed vascular remodeling of AVFs. Thus, a strategy to temporal regulate Notch activation will improve AVF maturation.
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Affiliation(s)
- Qunying Guo
- grid.12981.330000 0001 2360 039XDepartment of Nephrology, Key Laboratory of Nephrology, The First Affiliated Hospital, Sun Yat-sen University, Ministry of Health and Guangdong Province, Guangzhou, China ,grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA
| | - Guang Chen
- grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA ,grid.33199.310000 0004 0368 7223 Department of Integrated Traditional Chinese and Western Medicine, Tongji Medical College, Huangzhong University of Science and Technology, Wuhan, China
| | - Hunter Cheng
- grid.240145.60000 0001 2291 4776Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA
| | - Ying Qing
- grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA
| | - Luan Truong
- grid.63368.380000 0004 0445 0041Department of Pathology, Houston Methodist Hospital, Houston, TX 77030 USA
| | - Quan Ma
- grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA
| | - Yun Wang
- grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA
| | - Jizhong Cheng
- grid.39382.330000 0001 2160 926XSection of Nephrology, Department of Medicine, Selzman Institute for Kidney Health, Baylor College of Medicine, Houston, TX 77030 USA
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Liang S, Desai AA, Black SM, Tang H. Cytokines, Chemokines, and Inflammation in Pulmonary Arterial Hypertension. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1303:275-303. [PMID: 33788198 DOI: 10.1007/978-3-030-63046-1_15] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
According to the World Symposium Pulmonary Hypertension (WSPH) classification, pulmonary hypertension (PH) is classified into five categories based on etiology. Among them, Group 1 pulmonary arterial hypertension (PAH) disorders are rare but progressive and often, fatal despite multiple approved treatments. Elevated pulmonary arterial pressure in patients with WSPH Group 1 PAH is mainly caused by increased pulmonary vascular resistance (PVR), due primarily to sustained pulmonary vasoconstriction and excessive obliterative pulmonary vascular remodeling. Growing evidence indicates that inflammation plays a critical role in the development of pulmonary vascular remodeling associated with PAH. While the role of auto-immunity is unclear, infiltration of inflammatory cells in and around vascular lesions, including T- and B-cells, dendritic cells, macrophages, and mast cells have been observed in PAH patients. Serum and plasma levels of chemokines, cytokines, and autoantibodies are also increased in PAH patients; some of these circulating molecules are correlated with disease severity and survival. Preclinical experiments have reported a key role of the inflammation in PAH pathophysiology in vivo. Importantly, anti-inflammatory and immunosuppressive agents have further exhibited therapeutic effects. The present chapter reviews published experimental and clinical evidence highlighting the canonical role of inflammation in the pathogenesis of PAH and as a major target for the development of anti-inflammatory therapies in patients with PAH.
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Affiliation(s)
- Shuxin Liang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.,State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangdong Key Laboratory of Vascular Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Ankit A Desai
- Department of Medicine, Indiana University, Indianapolis, IN, USA
| | - Stephen M Black
- Division of Translational and Regenerative Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Haiyang Tang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. .,State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangdong Key Laboratory of Vascular Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
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Mamazhakypov A, Viswanathan G, Lawrie A, Schermuly RT, Rajagopal S. The role of chemokines and chemokine receptors in pulmonary arterial hypertension. Br J Pharmacol 2019; 178:72-89. [PMID: 31399998 DOI: 10.1111/bph.14826] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 12/11/2022] Open
Abstract
Pulmonary arterial hypertension (PAH) is characterized by progressive pulmonary artery remodelling leading to increased right ventricular pressure overload, which results in right heart failure and premature death. Inflammation plays a central role in the development of PAH, and the recruitment and function of immune cells are tightly regulated by chemotactic cytokines called chemokines. A number of studies have shown that the development and progression of PAH are associated with the dysregulated expression of several chemokines and chemokine receptors in the pulmonary vasculature. Moreover, some chemokines are differentially regulated in the pressure-overloaded right ventricle. Recent studies have tested the efficacy of pharmacological agents targeting several chemokines and chemokine receptors for their effects on the development of PAH, suggesting that these receptors could serve as useful therapeutic targets. In this review, we provide recent insights into the role of chemokines and chemokine receptors in PAH and RV remodelling and the opportunities and roadblocks in targeting them. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.1/issuetoc.
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Affiliation(s)
- Argen Mamazhakypov
- Department of Internal Medicine, Member of the German Center for Lung Research (DZL), Justus Liebig University of Giessen, Giessen, Germany
| | - Gayathri Viswanathan
- Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Allan Lawrie
- Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, UK
| | - Ralph Theo Schermuly
- Department of Internal Medicine, Member of the German Center for Lung Research (DZL), Justus Liebig University of Giessen, Giessen, Germany
| | - Sudarshan Rajagopal
- Division of Cardiology, Department of Medicine, Duke University Medical Center, Durham, NC, USA
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Quercetin Inhibits Pulmonary Arterial Endothelial Cell Transdifferentiation Possibly by Akt and Erk1/2 Pathways. BIOMED RESEARCH INTERNATIONAL 2017; 2017:6147294. [PMID: 28428963 PMCID: PMC5385898 DOI: 10.1155/2017/6147294] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 02/18/2017] [Accepted: 02/23/2017] [Indexed: 12/20/2022]
Abstract
This study aimed to investigate the effects and mechanisms of quercetin on pulmonary arterial endothelial cell (PAEC) transdifferentiation into smooth muscle-like cells. TGF-β1-induced PAEC transdifferentiation models were applied to evaluate the pharmacological actions of quercetin. PAEC proliferation was detected with CCK8 method and BurdU immunocytochemistry. Meanwhile, the identification and transdifferentiation of PAECs were determined by FVIII immunofluorescence staining and α-SMA protein expression. The related mechanism was elucidated based on the levels of Akt and Erk1/2 signal pathways. As a result, quercetin effectively inhibited the TGF-β1-induced proliferation and transdifferentiation of the PAECs and activation of Akt/Erk1/2 cascade in the cells. In conclusion, quercetin is demonstrated to be effective for pulmonary arterial hypertension (PAH) probably by inhibiting endothelial transdifferentiation possibly via modulating Akt and Erk1/2 expressions.
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Sahoo S, Meijles DN, Al Ghouleh I, Tandon M, Cifuentes-Pagano E, Sembrat J, Rojas M, Goncharova E, Pagano PJ. MEF2C-MYOCD and Leiomodin1 Suppression by miRNA-214 Promotes Smooth Muscle Cell Phenotype Switching in Pulmonary Arterial Hypertension. PLoS One 2016; 11:e0153780. [PMID: 27144530 PMCID: PMC4856285 DOI: 10.1371/journal.pone.0153780] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 04/04/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Vascular hyperproliferative disorders are characterized by excessive smooth muscle cell (SMC) proliferation leading to vessel remodeling and occlusion. In pulmonary arterial hypertension (PAH), SMC phenotype switching from a terminally differentiated contractile to synthetic state is gaining traction as our understanding of the disease progression improves. While maintenance of SMC contractile phenotype is reportedly orchestrated by a MEF2C-myocardin (MYOCD) interplay, little is known regarding molecular control at this nexus. Moreover, the burgeoning interest in microRNAs (miRs) provides the basis for exploring their modulation of MEF2C-MYOCD signaling, and in turn, a pro-proliferative, synthetic SMC phenotype. We hypothesized that suppression of SMC contractile phenotype in pulmonary hypertension is mediated by miR-214 via repression of the MEF2C-MYOCD-leiomodin1 (LMOD1) signaling axis. METHODS AND RESULTS In SMCs isolated from a PAH patient cohort and commercially obtained hPASMCs exposed to hypoxia, miR-214 expression was monitored by qRT-PCR. miR-214 was upregulated in PAH- vs. control subject hPASMCs as well as in commercially obtained hPASMCs exposed to hypoxia. These increases in miR-214 were paralleled by MEF2C, MYOCD and SMC contractile protein downregulation. Of these, LMOD1 and MEF2C were directly targeted by the miR. Mir-214 overexpression mimicked the PAH profile, downregulating MEF2C and LMOD1. AntagomiR-214 abrogated hypoxia-induced suppression of the contractile phenotype and its attendant proliferation. Anti-miR-214 also restored PAH-PASMCs to a contractile phenotype seen during vascular homeostasis. CONCLUSIONS Our findings illustrate a key role for miR-214 in modulation of MEF2C-MYOCD-LMOD1 signaling and suggest that an antagonist of miR-214 could mitigate SMC phenotype changes and proliferation in vascular hyperproliferative disorders including PAH.
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Affiliation(s)
- Sanghamitra Sahoo
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Daniel N. Meijles
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Imad Al Ghouleh
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Manuj Tandon
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Eugenia Cifuentes-Pagano
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - John Sembrat
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Mauricio Rojas
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Elena Goncharova
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Division of Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
| | - Patrick J. Pagano
- Department of Pharmacology and Chemical Biology University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261, United States of America
- * E-mail:
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Xu D, Gu JT, Yi B, Chen L, Wang GS, Qian GS, Lu KZ. Requirement of miR-9-dependent regulation of Myocd in PASMCs phenotypic modulation and proliferation induced by hepatopulmonary syndrome rat serum. J Cell Mol Med 2015; 19:2453-61. [PMID: 26147104 PMCID: PMC4594686 DOI: 10.1111/jcmm.12631] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/13/2015] [Indexed: 12/18/2022] Open
Abstract
Hepatopulmonary syndrome (HPS) is characterized by a triad of severe liver disease, intrapulmonary vascular dilation and hypoxaemia. Pulmonary vascular remodelling (PVR) is a key feature of HPS pathology. Our previous studies have established the role of the pulmonary artery smooth muscle cell (PASMC) phenotypic modulation and proliferation in HPS-associated PVR. Myocardin, a robust transcriptional coactivator of serum response factor, plays a critical role in the vascular smooth muscle cell phenotypic switch. However, the mechanism regulating myocardin upstream signalling remains unclear. In this study, treatment of rat PASMCs with serum drawn from common bile duct ligation rats, which model symptoms of HPS, resulted in a significant increase in miR-9 expression correlated with a decrease in expression of myocardin and the phenotypic markers SM-α-actin and smooth muscle-specific myosin heavy chain (SM-MHC). Furthermore, miRNA functional analysis and luciferase reporter assay demonstrated that miR-9 effectively regulated myocardin expression by directly binding to its 3′-untranslated region. Both the knockdown of miR-9 and overexpression of myocardin effectively attenuated the HPS rat serum-induced phenotype switch and proliferation of PASMCs. Taken together, the findings of our present study demonstrate that miR-9 is required in HPS rat serum-induced phenotypic modulation and proliferation of PASMCs for targeting of myocardin and that miR-9 may serve as a potential therapeutic target in HPS.
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Affiliation(s)
- Duo Xu
- Department of Anaesthesia, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Jian-teng Gu
- Department of Anaesthesia, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Bin Yi
- Department of Anaesthesia, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Lin Chen
- Department of Anaesthesia, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Guan-song Wang
- Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Gui-sheng Qian
- Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Chongqing, China
| | - Kai-zhi Lu
- Department of Anaesthesia, Southwest Hospital, Third Military Medical University, Chongqing, China
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Abstract
Myocardin (MYOCD) is a potent transcriptional coactivator that functions primarily in cardiac muscle and smooth muscle through direct contacts with serum response factor (SRF) over cis elements known as CArG boxes found near a number of genes encoding for contractile, ion channel, cytoskeletal, and calcium handling proteins. Since its discovery more than 10 years ago, new insights have been obtained regarding the diverse isoforms of MYOCD expressed in cells as well as the regulation of MYOCD expression and activity through transcriptional, post-transcriptional, and post-translational processes. Curiously, there are a number of functions associated with MYOCD that appear to be independent of contractile gene expression and the CArG-SRF nucleoprotein complex. Further, perturbations in MYOCD gene expression are associated with an increasing number of diseases including heart failure, cancer, acute vessel disease, and diabetes. This review summarizes the various biological and pathological processes associated with MYOCD and offers perspectives to several challenges and future directions for further study of this formidable transcriptional coactivator.
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Affiliation(s)
- Joseph M Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
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Jie W, He QY, Luo BT, Zheng SJ, Kong YQ, Jiang HG, Li RJ, Guo JL, Shen ZH. Inhibition of Pim-1 attenuates the proliferation and migration in nasopharyngeal carcinoma cells. ASIAN PAC J TROP MED 2012; 5:645-50. [PMID: 22840454 DOI: 10.1016/s1995-7645(12)60132-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 05/15/2012] [Accepted: 07/15/2012] [Indexed: 10/28/2022] Open
Abstract
OBJECTIVE To explore the role of proto-oncogene Pim-1 in the proliferation and migration of nasopharyngeal carcinoma (NPC) cells. METHODS Pim-1 expressions in NPC cell lines CNE1, CNE1-GL, CNE-2Z and C666-1 were examined by RT-PCR, western blotting and immunoflucesence, respectively. After CNE1, CNE1-GL and C666-1 cells were treated with different concentrations of Pim-1 special inhibitor, quercetagetin, the cell viability, colony formation rate and migration ability were analyzed. RESULTS Pim-1 expression was negative in well-differentiated CNE1 cells, whereas expressed weakly positive in poor-differentiated CNE-2Z cells and strongly positive in undifferentiated C666-1 cells. Interestingly, CNE1-GL cells that derived from CNE1 transfected with an Epstein Barr virus latent membrane protein-1 over-expression plasmid displayed stronger expression of Pim-1. Treatment of CNE1-GL and C666-1 cells with quercetagetin significantly decreased the cell viability, colony formation rate and migration ability but not the CNE1 cells. CONCLUSIONS These findings suggest that Pim-1 overexpression contributes to NPC proliferation and migration, and targeting Pim-1 may be a potential treatment for anti-Pim-1-expressed NPCs.
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Affiliation(s)
- Wei Jie
- Department of Pathology & Pathophysiology, School of Basic Medicine Science, Guangdong Medical College, Zhanjiang 524023, PR China
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Chettimada S, Rawat DK, Dey N, Kobelja R, Simms Z, Wolin MS, Lincoln TM, Gupte SA. Glc-6-PD and PKG contribute to hypoxia-induced decrease in smooth muscle cell contractile phenotype proteins in pulmonary artery. Am J Physiol Lung Cell Mol Physiol 2012; 303:L64-74. [PMID: 22582112 DOI: 10.1152/ajplung.00002.2012] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Persistent hypoxic pulmonary vasoconstriction (HPV) plays a significant role in the pathogenesis of pulmonary hypertension, which is an emerging clinical problem around the world. We recently showed that hypoxia-induced activation of glucose-6-phosphate dehydrogenase (Glc-6-PD) in pulmonary artery smooth muscle links metabolic changes within smooth muscle cells to HPV and that inhibition of Glc-6PD reduces acute HPV. Here, we demonstrate that exposing pulmonary arterial rings to hypoxia (20-30 Torr) for 12 h in vitro significantly (P < 0.05) reduces (by 30-50%) SM22α and smooth muscle myosin heavy chain expression and evokes HPV. Glc-6-PD activity was also elevated in hypoxic pulmonary arteries. Inhibition of Glc-6-PD activity prevented the hypoxia-induced reduction in SM22α expression and inhibited HPV by 80-90% (P < 0.05). Furthermore, Glc-6-PD and protein kinase G (PKG) formed a complex in pulmonary artery, and Glc-6-PD inhibition increased PKG-mediated phosphorylation of VASP (p-VASP). In turn, increasing PKG activity upregulated SM22α expression and attenuated HPV evoked by Glc-6-PD inhibition. Increasing passive tension (from 0.8 to 3.0 g) in hypoxic arteries for 12 h reduced Glc-6-PD, increased p-VASP and SM22α levels, and inhibited HPV. The present findings indicate that increases in Glc-6-PD activity influence PKG activity and smooth muscle cell phenotype proteins, all of which affect pulmonary artery contractility and remodeling.
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Affiliation(s)
- Sukrutha Chettimada
- Department of Biochemistry & Molecular Biology, College of Medicine, University of South Alabama, Mobile, AL 36688, USA
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