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Bordan Z, Batori RK, Haigh S, Li X, Meadows ML, Brown ZL, West MA, Dong K, Han W, Su Y, Ma Q, Huo Y, Zhou J, Abdelbary M, Sullivan JC, Weintraub NL, Stepp DW, Chen F, Barman SA, Fulton DJR. PDZ-Binding Kinase, a Novel Regulator of Vascular Remodeling in Pulmonary Arterial Hypertension. Circulation 2024; 150:393-410. [PMID: 38682326 DOI: 10.1161/circulationaha.123.067095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 03/04/2024] [Indexed: 05/01/2024]
Abstract
BACKGROUND Pulmonary arterial hypertension (PAH) is high blood pressure in the lungs that originates from structural changes in small resistance arteries. A defining feature of PAH is the inappropriate remodeling of pulmonary arteries (PA) leading to right ventricle failure and death. Although treatment of PAH has improved, the long-term prognosis for patients remains poor, and more effective targets are needed. METHODS Gene expression was analyzed by microarray, RNA sequencing, quantitative polymerase chain reaction, Western blotting, and immunostaining of lung and isolated PA in multiple mouse and rat models of pulmonary hypertension (PH) and human PAH. PH was assessed by digital ultrasound, hemodynamic measurements, and morphometry. RESULTS Microarray analysis of the transcriptome of hypertensive rat PA identified a novel candidate, PBK (PDZ-binding kinase), that was upregulated in multiple models and species including humans. PBK is a serine/threonine kinase with important roles in cell proliferation that is minimally expressed in normal tissues but significantly increased in highly proliferative tissues. PBK was robustly upregulated in the medial layer of PA, where it overlaps with markers of smooth muscle cells. Gain-of-function approaches show that active forms of PBK increase PA smooth muscle cell proliferation, whereas silencing PBK, dominant negative PBK, and pharmacological inhibitors of PBK all reduce proliferation. Pharmacological inhibitors of PBK were effective in PH reversal strategies in both mouse and rat models, providing translational significance. In a complementary genetic approach, PBK was knocked out in rats using CRISPR/Cas9 editing, and loss of PBK prevented the development of PH. We found that PBK bound to PRC1 (protein regulator of cytokinesis 1) in PA smooth muscle cells and that multiple genes involved in cytokinesis were upregulated in experimental models of PH and human PAH. Active PBK increased PRC1 phosphorylation and supported cytokinesis in PA smooth muscle cells, whereas silencing or dominant negative PBK reduced cytokinesis and the number of cells in the G2/M phase of the cell cycle. CONCLUSIONS PBK is a newly described target for PAH that is upregulated in proliferating PA smooth muscle cells, where it contributes to proliferation through changes in cytokinesis and cell cycle dynamics to promote medial thickening, fibrosis, increased PA resistance, elevated right ventricular systolic pressure, right ventricular remodeling, and PH.
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Affiliation(s)
- Zsuzsanna Bordan
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Robert K Batori
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Stephen Haigh
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Xueyi Li
- Departments of Ophthalmology and Medicine, Stanford University School of Medicine, Palo Alto, CA (X.L.)
| | - Mary Louise Meadows
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Zach L Brown
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Madison A West
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Kunzhe Dong
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Weihong Han
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Yunchao Su
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Qian Ma
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Yuqing Huo
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Jiliang Zhou
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Mahmoud Abdelbary
- School of Medicine, Oregon Health & Science University, Portland (M.A.)
| | - Jennifer C Sullivan
- Immunology Center of Georgia (K.D.), Department of Physiology (J.C.S.), Medical College of Georgia, Augusta University
| | - Neal L Weintraub
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - David W Stepp
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
| | - Feng Chen
- Department of Forensic Medicine, Nanjing Medical University, China (F.C.)
| | - Scott A Barman
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
| | - David J R Fulton
- Vascular Biology Center (Z.B., R.K.B., S.H., Z.L.B., M.A.W., Q.M., Y.H., N.L.W., D.W.S., D.J.R.F.), Medical College of Georgia, Augusta University
- Department of Pharmacology and Toxicology (M.L.M., W.H., Y.S., J.Z., S.A.B., D.J.R.F.), Medical College of Georgia, Augusta University
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2
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Woo KV, Shen IY, Weinheimer CJ, Kovacs A, Nigro J, Lin CY, Chakinala M, Byers DE, Ornitz DM. Endothelial FGF signaling is protective in hypoxia-induced pulmonary hypertension. J Clin Invest 2021; 131:141467. [PMID: 34623323 DOI: 10.1172/jci141467] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 06/25/2021] [Indexed: 01/08/2023] Open
Abstract
Hypoxia-induced pulmonary hypertension (PH) is one of the most common and deadliest forms of PH. Fibroblast growth factor receptors 1 and 2 (FGFR1/2) are elevated in patients with PH and in mice exposed to chronic hypoxia. Endothelial FGFR1/2 signaling is important for the adaptive response to several injury types and we hypothesized that endothelial FGFR1/2 signaling would protect against hypoxia-induced PH. Mice lacking endothelial FGFR1/2, mice with activated endothelial FGFR signaling, and human pulmonary artery endothelial cells (HPAECs) were challenged with hypoxia. We assessed the effect of FGFR activation and inhibition on right ventricular pressure, vascular remodeling, and endothelial-mesenchymal transition (EndMT), a known pathologic change seen in patients with PH. Hypoxia-exposed mice lacking endothelial FGFRs developed increased PH, while mice overexpressing a constitutively active FGFR in endothelial cells did not develop PH. Mechanistically, lack of endothelial FGFRs or inhibition of FGFRs in HPAECs led to increased TGF-β signaling and increased EndMT in response to hypoxia. These phenotypes were reversed in mice with activated endothelial FGFR signaling, suggesting that FGFR signaling inhibits TGF-β pathway-mediated EndMT during chronic hypoxia. Consistent with these observations, lung tissue from patients with PH showed activation of FGFR and TGF-β signaling. Collectively, these data suggest that activation of endothelial FGFR signaling could be therapeutic for hypoxia-induced PH.
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Affiliation(s)
- Kel Vin Woo
- Division of Cardiology, Department of Pediatrics.,Department of Developmental Biology
| | | | | | | | | | | | - Murali Chakinala
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Derek E Byers
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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Liu C, Chen X, Guo G, Xu X, Li X, Wei Q, Shen Y, Li H, Hao J, Tian YP, He K. Effects of Intermittent Normoxia on Chronic Hypoxic Pulmonary Hypertension and Right Ventricular Hypertrophy in Rats. High Alt Med Biol 2021; 22:184-192. [PMID: 33989063 DOI: 10.1089/ham.2020.0110] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Liu, Chunlei, Xu Chen, Ge Guo, Xiang Xu, Xin Li, Qingxia Wei, Yanying Shen, Hanlu Li, Jianxiu Hao, Ya Ping Tian, and Kunlun He. Effects of intermittent normoxia on chronic hypoxic pulmonary hypertension and right ventricular hypertrophy in rats. High Alt Med Biol. 22: 184-192, 2021. Background: Individuals with chronically low arterial oxygen tension owing to high altitude develop elevated rates of pulmonary hypertension (PH) and right ventricular (RV) hypertrophy. However, the effects of the frequency and duration of normoxic exposure on PH and RV hypertrophy have not been adequately assessed; thus, we aimed to analyze the same. Materials and Methods: PH and RV hypertrophy were induced in 60 rats using a hypobaric chamber. Of these 60 rats, every 10 were exposed to normoxic conditions for 30 minutes once (1T/D), three times (3T/D), or five times daily (5T/D), or for one 150-minute recovery daily (1LT/D). Furthermore, 10 rats were housed in a normoxic environment, and another 10 were subjected to continuous hypoxia. After 4 weeks, hemodynamic measurements were recorded, and the hearts were harvested for pathomorphological observations. Results: Average pulmonary arterial pressures (PAP) of control rats and those exposed to hypobaric hypoxia were 14.1 and 32.3 mmHg, respectively. After 30 minutes of exposure to normoxia 3T/D, 5T/D, or 1LT/D, PAP values were reduced to 27.1, 27.9, or 26.8 mmHg, respectively. Four weeks of hypoxic exposure elevated the RV/heart weight (HW) ratios, while exposure to normoxia 3T/D, 5T/D, and 1LT/D significantly reduced RV/HW. In addition, exposure to normoxia 3T/D, 5T/D, 1LT/D reduced the percentage wall thickness of the pulmonary artery as well as the hypertrophy indices of atrial natriuretic peptide, brain natriuretic peptide, and myosin heavy chain 7 (MYH-7). Conclusions: Thirty-minute exposure to normoxic conditions of 3T/D, 5T/D, or 1LT/D effectively ameliorates PH and RV thickening.
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Affiliation(s)
- Chunlei Liu
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China.,Beijing Key Laboratory of Chronic Heart Failure Precision Medicine, Chinese PLA General Hospital, Beijing, China
| | - Xu Chen
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Ge Guo
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Xiang Xu
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Xin Li
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China.,Beijing Key Laboratory of Chronic Heart Failure Precision Medicine, Chinese PLA General Hospital, Beijing, China
| | - Qingxia Wei
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Yanying Shen
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Hanlu Li
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Jianxiu Hao
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China
| | - Ya Ping Tian
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China.,Beijing Key Laboratory of Chronic Heart Failure Precision Medicine, Chinese PLA General Hospital, Beijing, China
| | - Kunlun He
- Transformation Medicine Centre, Chinese PLA General Hospital, Beijing, China.,Beijing Key Laboratory of Chronic Heart Failure Precision Medicine, Chinese PLA General Hospital, Beijing, China
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Zhu J, Kang J, Li X, Wang M, Shang M, Luo Y, Xiong M, Hu K. Chronic intermittent hypoxia vs chronic continuous hypoxia: Effects on vascular endothelial function and myocardial contractility. Clin Hemorheol Microcirc 2020; 74:417-427. [PMID: 31683472 DOI: 10.3233/ch-190706] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIM Both chronic intermittent hypoxia (CIH) and chronic continuous hypoxia (CCH) are risk factors for cardiovascular disease, which are associated with cardiac systolic function and associated with dysfunction of endothelia and coagulation-fibrinolysis system in the vasculature. However, the different effects of these two hypoxic models are not fully understood. In our study, we systemically compared the effects of CIH and CCH on cardiac function and related factor levels in serum using rat model. METHODS Forty-five male Sprague-Dawley rats were randomly divided into the normoxia control (NC), CIH and CCH groups. The rat CIH and CCH models were established, then the blood and tissue samples were collected to analyze the function of endothelium and the coagulation-fibrinolysis system. Also, the ultrasound cardiogram was performed to directly assess myocardial contractility. RESULTS Both CIH and CCH significantly decreased the NO, eNOS, P-eNOS and AT-III levels in the rat serum but significantly increased the levels of ET-1, vWF, COX-2, NF-κB, FIB, FVIII and PAI-1 in the rat serum (P < 0.05). The expression of ET-1, VWF and ICAM-1 in CIH group were higher than CCH group (P < 0.05), however, the expression of CD62p was increased in CCH group but not in CIH group. The expression of t-PA in CIH group were lower than CCH group (P < 0.05), but there were no significant differences in CCH group and NC group (P > 0.05). Using transmission electron microscope, we found that the mitochondrial ultrastructure of thoracic aorta endothelial cells in CIH and CCH group were damaged. Moreover, the myocardial contractility in CIH and CCH group were significantly decreased compared with NC group. CONCLUSION Our results suggested that CIH and CCH could cause endothelial dysfunction, dysfunction of the coagulation-fibrinolysis system and decreasing of myocardial contractility. Compared with CCH, CIH has greater effect on vasoconstriction and adhesion of vascular endothelial cells, and stronger procoagulant effect.
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Affiliation(s)
- Jing Zhu
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Jing Kang
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Xiaochen Li
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Mengmei Wang
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Min Shang
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Yuchuan Luo
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Mengqing Xiong
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Ke Hu
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
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5
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Wang X, Lin L, Chai X, Wu Y, Li Y, Liu X. Hypoxic mast cells accelerate the proliferation, collagen accumulation and phenotypic alteration of human lung fibroblasts. Int J Mol Med 2020; 45:175-185. [PMID: 31746371 PMCID: PMC6889934 DOI: 10.3892/ijmm.2019.4400] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Accepted: 10/09/2019] [Indexed: 12/21/2022] Open
Abstract
Pulmonary vascular remodeling and fibrosis are the critical pathological characteristics of hypoxic pulmonary hypertension. Our previous study demonstrated that hypoxia is involved in the functional alteration of lung fibroblasts, but the underlying mechanism has yet to be fully elucidated. The aim of the present study was to investigate the effect of mast cells on the proliferation, function and phenotype of fibroblasts under hypoxic conditions. Hypoxia facilitated proliferation and the secretion of proinflammatory cytokines, including tumor necrosis factor (TNF)‑α and interleukin (IL)‑6, in human mast cells (HMC‑1). RNA sequencing identified 2,077 upregulated and 2,418 downregulated mRNAs in human fetal lung fibroblasts (HFL‑1) cultured in hypoxic conditioned medium from HMC‑1 cells compared with normoxic controls, which are involved in various pathways, including extracellular matrix organization, cell proliferation and migration. Conditioned medium from hypoxic HMC‑1 cells increased the proliferation and migration capacity of HFL‑1 and triggered phenotypic transition from fibroblasts to myofibroblasts. A greater accumulation of collagen type I and III was also observed in an HFL‑1 cell culture in hypoxic conditioned medium from HMC‑1 cells, compared with HFL‑1 cells cultured in normoxic control medium. The expression of matrix metalloproteinase (MMP)‑9 and MMP‑13 was upregulated in HFL‑1 cells grown in hypoxic conditioned medium from HMC‑1 cells. Similar pathological phenomena, including accumulation of mast cells, activated collagen metabolism and vascular remodeling, were observed in a hypoxic rat model. The results of the present study provide direct evidence that the multiple effects of the hypoxic microenvironment and mast cells on fibroblasts contribute to pulmonary vascular remodeling, and this process appears to be among the most important mechanisms underlying hypoxic pulmonary hypertension.
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Affiliation(s)
| | | | | | | | | | - Xinmin Liu
- Correspondence to: Professor Xinmin Liu, Department of Geriatrics, Peking University First Hospital, 8 Xishiku Street, Beijing 100034, P.R. China, E-mail:
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Rashid J, Nozik-Grayck E, McMurtry IF, Stenmark KR, Ahsan F. Inhaled combination of sildenafil and rosiglitazone improves pulmonary hemodynamics, cardiac function, and arterial remodeling. Am J Physiol Lung Cell Mol Physiol 2019; 316:L119-L130. [PMID: 30307312 PMCID: PMC6383494 DOI: 10.1152/ajplung.00381.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/01/2018] [Accepted: 10/01/2018] [Indexed: 01/15/2023] Open
Abstract
Currently, dual- or triple-drug combinations comprising different vasodilators are the mainstay for the treatment of pulmonary arterial hypertension (PAH). However, the patient outcome continues to be disappointing because the existing combination therapy cannot restrain progression of the disease. Previously, we have shown that when given as a monotherapy, long-acting inhaled formulations of sildenafil (a phosphodiesterase-5 inhibitor) and rosiglitazone (a peroxisome proliferator receptor-γ agonist) ameliorate PAH in rats. Thus, with a goal to develop a new combination therapy, we prepared and characterized poly(lactic-co-glycolic acid) (PLGA)-based long-acting inhalable particles of sildenafil and rosiglitazone. We then assessed the efficacy of the combinations of sildenafil and rosiglitazone, given in plain forms or as PLGA particles, in reducing mean pulmonary arterial pressure (mPAP) and improving pulmonary arterial remodeling and right ventricular hypertrophy (RVH) in Sugen 5416 plus hypoxia-induced PAH rats. After intratracheal administration of the formulations, we catheterized the rats and measured mPAP, cardiac output, total pulmonary resistance, and RVH. We also conducted morphometric studies using lung tissue samples and assessed the degree of muscularization, the arterial medial wall thickening, and the extent of collagen deposition. Compared with the plain drugs, given via the pulmonary or oral route as a single or dual combination, PLGA particles of the drugs, although given at a longer dosing interval compared with the plain drugs, caused more pronounced reduction in mPAP without affecting mean systemic pressure, improved cardiac function, slowed down right heart remodeling, and reduced arterial muscularization. Overall, PLGA particles of sildenafil and rosiglitazone, given as an inhaled combination, could be a viable alternative to currently available vasodilator-based combination therapy for PAH.
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Affiliation(s)
- Jahidur Rashid
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center , Amarillo, Texas
| | - Eva Nozik-Grayck
- Department of Pediatrics, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Ivan F McMurtry
- Department of Pharmacology, Center for Lung Biology, University of South Alabama , Mobile, Alabama
| | - Kurt R Stenmark
- Department of Pediatrics, University of Colorado Anschutz Medical Campus , Aurora, Colorado
| | - Fakhrul Ahsan
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center , Amarillo, Texas
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7
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Thenappan T, Chan SY, Weir EK. Role of extracellular matrix in the pathogenesis of pulmonary arterial hypertension. Am J Physiol Heart Circ Physiol 2018; 315:H1322-H1331. [PMID: 30141981 PMCID: PMC6297810 DOI: 10.1152/ajpheart.00136.2018] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 08/06/2018] [Accepted: 08/14/2018] [Indexed: 12/23/2022]
Abstract
Pulmonary arterial hypertension (PAH) is characterized by remodeling of the extracellular matrix (ECM) of the pulmonary arteries with increased collagen deposition, cross-linkage of collagen, and breakdown of elastic laminae. Extracellular matrix remodeling occurs due to an imbalance in the proteolytic enzymes, such as matrix metalloproteinases, elastases, and lysyl oxidases, and tissue inhibitor of matrix metalloproteinases, which, in turn, results from endothelial cell dysfunction, endothelial-to-mesenchymal transition, and inflammation. ECM remodeling and pulmonary vascular stiffness occur early in the disease process, before the onset of the increase in the intimal and medial thickness and pulmonary artery pressure, suggesting that the ECM is a cause rather than a consequence of distal pulmonary vascular remodeling. ECM remodeling and increased pulmonary arterial stiffness promote proliferation of pulmonary vascular cells (endothelial cells, smooth muscle cells, and adventitial fibroblasts) through mechanoactivation of various signaling pathways, including transcriptional cofactors YAP/TAZ, transforming growth factor-β, transient receptor potential channels, Toll-like receptor, and NF-κB. Inhibition of ECM remodeling and mechanotransduction prevents and reverses experimental pulmonary hypertension. These data support a central role for ECM remodeling in the pathogenesis of the PAH, making it an attractive novel therapeutic target.
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Affiliation(s)
- Thenappan Thenappan
- Cardiovascular Division, Department of Medicine, University of Minnesota , Minneapolis, Minnesota
| | - Stephen Y Chan
- Center for Pulmonary Vascular Biology and Medicine, Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Division of Cardiology, Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
- University of Pittsburgh Medical Center, Pennsylvania
| | - E Kenneth Weir
- Cardiovascular Division, Department of Medicine, University of Minnesota , Minneapolis, Minnesota
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8
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Grosche J, Meißner J, Eble JA. More than a syllable in fib-ROS-is: The role of ROS on the fibrotic extracellular matrix and on cellular contacts. Mol Aspects Med 2018; 63:30-46. [PMID: 29596842 DOI: 10.1016/j.mam.2018.03.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/16/2018] [Accepted: 03/21/2018] [Indexed: 01/01/2023]
Abstract
Fibrosis is characterized by excess deposition of extracellular matrix (ECM). However, the ECM changes during fibrosis not only quantitatively but also qualitatively. Thus, the composition is altered as the expression of various ECM proteins changes. Moreover, also posttranslational modifications, secretion, deposition and crosslinkage as well as the proteolytic degradation of ECM components run differently during fibrosis. As several of these processes involve redox reactions and some of them are even redox-regulated, reactive oxygen species (ROS) influence fibrotic diseases. Redox regulation of the ECM has not been studied intensively, although evidences exist that the alteration of the ECM, including the redox-relevant processes of its formation and degradation, may be of key importance not only as a cause but also as a consequence of fibrotic diseases. Myofibroblasts, which have differentiated from fibroblasts during fibrosis, produce most of the ECM components and in return obtain important environmental cues of the ECM, including their redox-dependent fibrotic alterations. Thus, myofibroblast differentiation and fibrotic changes of the ECM are interdependent processes and linked with each other via cell-matrix contacts, which are mediated by integrins and other cell adhesion molecules. These cell-matrix contacts are also regulated by redox processes and by ROS. However, most of the redox-catalyzing enzymes are localized within cells. Little is known about redox-regulating enzymes, especially the ones that control the formation and cleavage of redox-sensitive disulfide bridges within the extracellular space. They are also important players in the redox-regulative crosstalk between ECM and cells during fibrosis.
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Affiliation(s)
- Julius Grosche
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Waldeyerstr. 15, 48149 Münster, Germany
| | - Juliane Meißner
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Waldeyerstr. 15, 48149 Münster, Germany
| | - Johannes A Eble
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Waldeyerstr. 15, 48149 Münster, Germany.
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9
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Labrousse-Arias D, Martínez-Ruiz A, Calzada MJ. Hypoxia and Redox Signaling on Extracellular Matrix Remodeling: From Mechanisms to Pathological Implications. Antioxid Redox Signal 2017; 27:802-822. [PMID: 28715969 DOI: 10.1089/ars.2017.7275] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
SIGNIFICANCE The extracellular matrix (ECM) is an essential modulator of cell behavior that influences tissue organization. It has a strong relevance in homeostasis and translational implications for human disease. In addition to ECM structural proteins, matricellular proteins are important regulators of the ECM that are involved in a myriad of different pathologies. Recent Advances: Biochemical studies, animal models, and study of human diseases have contributed to the knowledge of molecular mechanisms involved in remodeling of the ECM, both in homeostasis and disease. Some of them might help in the development of new therapeutic strategies. This review aims to review what is known about some of the most studied matricellular proteins and their regulation by hypoxia and redox signaling, as well as the pathological implications of such regulation. CRITICAL ISSUES Matricellular proteins have complex regulatory functions and are modulated by hypoxia and redox signaling through diverse mechanisms, in some cases with controversial effects that can be cell or tissue specific and context dependent. Therefore, a better understanding of these regulatory processes would be of great benefit and will open new avenues of considerable therapeutic potential. FUTURE DIRECTIONS Characterizing the specific molecular mechanisms that modulate matricellular proteins in pathological processes that involve hypoxia and redox signaling warrants additional consideration to harness the potential therapeutic value of these regulatory proteins. Antioxid. Redox Signal. 27, 802-822.
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Affiliation(s)
- David Labrousse-Arias
- 1 Servicio de Inmunología, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP) , Madrid, Spain
| | - Antonio Martínez-Ruiz
- 1 Servicio de Inmunología, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP) , Madrid, Spain .,2 Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV) , Madrid, Spain
| | - María J Calzada
- 1 Servicio de Inmunología, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP) , Madrid, Spain .,3 Departmento de Medicina, Universidad Autónoma de Madrid , Madrid, Spain
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Aghasafari P, Bin M Ibrahim I, Pidaparti R. Strain-induced inflammation in pulmonary alveolar tissue due to mechanical ventilation. Biomech Model Mechanobiol 2017; 16:1103-1118. [PMID: 28194537 DOI: 10.1007/s10237-017-0879-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
Abstract
Inflammation is the body's attempt at self-protection to remove harmful stimuli, including damaged cells, irritants, or pathogens and begin the healing process. In this study, strain-induced inflammation in pulmonary alveolar tissue under high tidal volume is investigated through a combination of an inflammation model and fluid structure interaction (FSI) analysis. A realistic three-dimensional organ model for alveolar sacs is built, and FSI is employed to evaluate strain distribution in alveolar tissue for different tidal volume (TV) values under the mechanical ventilation (MV) condition. The alveolar tissue is treated as a hyperelastic solid and provides the environment for the tissue constituents. The influence of different strain distributions resulting from different tidal volumes is investigated. It is observed that strain is highly distributed in the inlet area. In addition, strain versus time curves in different locations through the alveolar model reveals that middle layers in the alveolar region would undergo higher levels of strain during breathing under the MV condition. Three different types of strain distributions in the alveolar region from the FSI simulation are transferred to the CA model to study population dynamics of cell constituents under MV for different TVs; 200, 500 and 1000 mL, respectively. The CA model results suggests that strain distribution plays a significant role in population dynamics. An interplay between strain magnitude and distribution appears to influence healing capability. Results suggest that increasing TV leads to an exponential rise in tissue damage by inflammation.
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Affiliation(s)
- Parya Aghasafari
- College of Engineering, UGA, 132A Paul D. Coverdell Center, Athens, GA, 30602, USA
| | - Israr Bin M Ibrahim
- College of Engineering, UGA, 132A Paul D. Coverdell Center, Athens, GA, 30602, USA
| | - Ramana Pidaparti
- College of Engineering, UGA, 132A Paul D. Coverdell Center, Athens, GA, 30602, USA.
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11
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Wang Z, Schreier DA, Abid H, Hacker TA, Chesler NC. Pulmonary vascular collagen content, not cross-linking, contributes to right ventricular pulsatile afterload and overload in early pulmonary hypertension. J Appl Physiol (1985) 2016; 122:253-263. [PMID: 27856711 DOI: 10.1152/japplphysiol.00325.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 11/03/2016] [Accepted: 11/11/2016] [Indexed: 12/14/2022] Open
Abstract
Hypoxic pulmonary hypertension (HPH) is associated with pulmonary artery (PA) remodeling and right ventricular (RV) overload. We have previously uncovered collagen-mediated mechanisms of proximal PA stiffening in early HPH by manipulating collagen degradation and cross-linking using a transgenic mouse strain and a potent collagen cross-link inhibitor, β-aminopropionitrile (BAPN). However, the roles of collagen in distal PA remodeling, overall RV afterload, and RV hypertrophy in HPH remain unknown. Here, we used the same experimental strategy to investigate the effect of pulmonary vascular collagen content and cross-linking on steady and pulsatile RV afterload and on RV hypertrophy in early HPH. Collagenase-resistant mice (Col1a1R/R) and their littermate controls (Col1a1+/+) were exposed to normobaric hypoxia for 10 days with or without BAPN treatment. In vivo pulmonary vascular impedance, a comprehensive measure of RV afterload, was measured via simultaneous RV catheterization and echocardiography. Morphology and collagen accumulation were examined using histological techniques and ELISA in lungs and RVs. In both mouse strains, BAPN did not limit increases in pulmonary arterial pressure or pulmonary vascular resistance, indicating a negligible effect of either collagen content or cross-linking on steady RV afterload. However, BAPN prevented the increase in pulse pressure and RV hypertrophy in Col1a1+/+ mice and these effects were absent in Col1a1R/R mice, suggesting a role for PA collagen content, not cross-linking, in the pulsatile RV afterload. Moreover, we found a significant correlation between pulse pressure and RV hypertrophy, indicating an important role for pulsatile RV afterload in RV overload in early HPH. NEW & NOTEWORTHY The present study found an important role for collagen content, but not collagen cross-linking, in the pulsatile right ventricular (RV) afterload, which is correlated with RV hypertrophy. These results uncover a new collagen-mediated mechanical mechanism of RV dysfunction in early pulmonary hypertension progression. Furthermore, our results suggest that measures and metrics of pulsatile hemodynamics such as pulse pressure and pulse wave velocity are potentially important to cardiovascular mortality in patients with pulmonary hypertension.
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Affiliation(s)
- Zhijie Wang
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Mechanical Engineering, Colorado State University, Fort Collins, Colorado; and
| | - David A Schreier
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hinnah Abid
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin
| | - Timothy A Hacker
- Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Naomi C Chesler
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin; .,Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin
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12
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Scarsini R, Prioli MA, Milano EG, Castellani C, Pesarini G, Assael BM, Vassanelli C, Ribichini FL. Hemodynamic predictors of long term survival in end stage cystic fibrosis. Int J Cardiol 2015; 202:221-5. [PMID: 26397415 DOI: 10.1016/j.ijcard.2015.09.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/08/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Pulmonary hypertension (PH) is often found in cystic fibrosis (CF) patients affected by end-stage lung disease but its impact on outcome remains unclear. Pulmonary arterial compliance (PAC) is an important determinant of right ventricle (RV) workload and it is a strong predictor of survival in other forms of PH. The aim of this study is to investigate whether PAC is a predictor of long-term prognosis in a population of CF patients affected by advanced lung disease. METHODS Between 2000 and 2014, 178 patients with CF have been evaluated for lung transplantation in our CF Center. Right heart catheterization (RHC) and follow up data were retrievable and analyzed in 141 of them. PAC was defined as the ratio between stroke volume (SV) and pulse pressure (PP) at heart catheterization. The association of PAC with survival was tested at 4 years and compared to other hemodynamic parameters. RESULTS PH prevalence was 56.4%. Most patients had mild elevation of pulmonary artery pressure (PAP). No difference in mortality was observed in patients with PH compared to patients with normal PAP (HR 0.95: 95% CI 0.49-1.89, p=0.89). At receiver operating characteristic curve (ROC) analysis, the optimal prognostic cut-off point of PAC was 1.95 ml/mmHg. An impaired PAC (≤1.95 ml/mmHg) was a strong independent predictor of long-term mortality (HR 3.44: 95% CI 1.51-7.85: p=0.003). CONCLUSIONS Impaired PAC is associated with poor prognosis in CF patients awaiting lung transplantation. Other traditional hemodynamic parameters add no prognostic information.
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Affiliation(s)
- Roberto Scarsini
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy.
| | - Maria A Prioli
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy
| | - Elena G Milano
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy
| | | | - Gabriele Pesarini
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy
| | | | - Corrado Vassanelli
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy
| | - Flavio L Ribichini
- Department of Medicine, Section of Cardiology, University of Verona, Verona, Italy
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13
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Liu P, Yan S, Chen M, Chen A, Yao D, Xu X, Cai X, Wang L, Huang X. Effects of baicalin on collagen Ι and collagen ΙΙΙ expression in pulmonary arteries of rats with hypoxic pulmonary hypertension. Int J Mol Med 2015; 35:901-8. [PMID: 25716558 PMCID: PMC4356435 DOI: 10.3892/ijmm.2015.2110] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Accepted: 02/13/2015] [Indexed: 01/10/2023] Open
Abstract
The synthesis and accumulation of collagen play an important role in the formation and progression of hypoxic pulmonary hypertension. Baicalin has been reported to prevent bleomycin-induced pulmonary fibrosis. However, the role of baicalin in the treatment of pulmonary hypertension remains unknown. A disintegrin and metalloprotease with thrombospondin type-1 motif (ADAMTS-1) is a secreted enzyme that acts on a wide variety of extracellular matrix (ECM) substrates associated with vascular diseases. In this study, we aimed to investigate the effects of baicalin on the synthesis of collagen I in rats with pulmonary hypertension induced by hypoxia and the changes in ADAMTS-1 expression. A total of 24 Sprague Dawley rats were randomly assigned to 3 groups as follows: the control group (C), the hypoxia group (H) and the hypoxia + baicalin group (B). The rats in groups H and B were kept in a normobaric hypoxic chamber for 4 weeks, and the rats in group C were exposed to room air. We measured the hemodynamic indexes, including mean pulmonary artery pressure (mPAP), mean systemic (carotid) artery pressure (mSAP), and then calculated the mass ratio of right ventricle to left ventricle plus septum [RV/(LV + S)] to reflect the extent of right ventricular hypertrophy. We measured the mRNA and protein expression levels of type I collagen, type III collagen and ADAMTS-1 by hybridization in situ, and immunohistochemistry and western blot analysis, respectively. The results revealed that treatment with baicalin significantly reduced pulmonary artery pressure and attenuated the remodeling of the pulmonary artery under hypoxic conditions by increasing the expression of ADAMTS-1, so that the synthesis of type I collagen and its mRNA expression were inhibited. In conclusion, baicalin effectively inhibits the synthesis of collagen I in pulmonary arteries and this is associated with an increase in the expression of ADAMTS-1. Thus, treatment with baicalin may be an effective method for lowering pulmonary artery pressure and preventing pulmonary artery remodeling.
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Affiliation(s)
- Panpan Liu
- Intensive Care Unit, Ningbo Medical Treatment Center Lihuili Hospital, Ningbo, Zhejiang 315040, P.R. China
| | - Shuangquan Yan
- Division of Respiratory Medicine, Taizhou Enze Medical Center Luqiao Hospital, Taizhou, Zhejiang 318050, P.R. China
| | - Mayun Chen
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Ali Chen
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Dan Yao
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Xiaomei Xu
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Xueding Cai
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Liangxing Wang
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
| | - Xiaoying Huang
- Division of Pulmonary Medicine, The First Affiliated Hospital of Wenzhou Medical University and Key Laboratory of Heart and Lung, Wenzhou, Zhejiang 325035, P.R. China
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14
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Gopal P, Gosker HR, Theije CCD, Eurlings IM, Sell DR, Monnier VM, Reynaert NL. Effect of chronic hypoxia on RAGE and its soluble forms in lungs and plasma of mice. Biochim Biophys Acta Mol Basis Dis 2015; 1852:992-1000. [PMID: 25703138 DOI: 10.1016/j.bbadis.2015.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 01/30/2015] [Accepted: 02/12/2015] [Indexed: 12/24/2022]
Abstract
The receptor for advanced glycation end products (RAGE) is a multi-ligand receptor. Alternative splicing and enzymatic shedding produce soluble forms that protect against damage by ligands including Advanced Glycation End products (AGEs). A link between RAGE and oxygen levels is evident from studies showing RAGE-mediated injury following hyperoxia. The effect of hypoxia on pulmonary RAGE expression and circulating sRAGE levels is however unknown. Therefore mice were exposed to chronic hypoxia for 21 d and expression of RAGE, sheddases in lungs and circulating sRAGE were determined. In addition, accumulation of AGEs in lungs and expression of the AGE detoxifying enzyme GLO1 and receptors were evaluated. In lung tissue gene expression of total RAGE, variants 1 and 3 were elevated in mice exposed to hypoxia, whereas mRAGE and sRAGE protein levels were decreased. In the hypoxic group plasma sRAGE levels were enhanced. Although the levels of pro-ADAM10 were elevated in lungs of hypoxia exposed mice, the relative amount of the active form was decreased and gelatinase activity unaffected. In the lungs, the RAGE ligand HMGB1 was decreased and of the AGEs, only LW-1 was increased by chronic hypoxia. Gene expression of AGE receptors 2 and 3 was significantly upregulated. Chronic hypoxia is associated with downregulation of pulmonary RAGE protein levels, but a relative increase in sRAGE. These alterations might be part of the adaptive and protective response mechanism to chronic hypoxia and are not associated with AGE formation except for the fluorophore LW-1 which emerges as a novel marker of tissue hypoxia.
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Affiliation(s)
- P Gopal
- Department of Respiratory Medicine, Maastricht University, Maastricht, The Netherlands
| | - H R Gosker
- Department of Respiratory Medicine, Maastricht University, Maastricht, The Netherlands
| | - C C de Theije
- Department of Respiratory Medicine, Maastricht University, Maastricht, The Netherlands
| | - I M Eurlings
- Department of Respiratory Medicine, Maastricht University, Maastricht, The Netherlands
| | - D R Sell
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - V M Monnier
- Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - N L Reynaert
- Department of Respiratory Medicine, Maastricht University, Maastricht, The Netherlands.
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15
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Rogers NM, Yao M, Sembrat J, George MP, Knupp H, Ross M, Sharifi-Sanjani M, Milosevic J, St Croix C, Rajkumar R, Frid MG, Hunter KS, Mazzaro L, Novelli EM, Stenmark KR, Gladwin MT, Ahmad F, Champion HC, Isenberg JS. Cellular, pharmacological, and biophysical evaluation of explanted lungs from a patient with sickle cell disease and severe pulmonary arterial hypertension. Pulm Circ 2014; 3:936-51. [PMID: 25006410 DOI: 10.1086/674754] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 09/10/2013] [Indexed: 12/31/2022] Open
Abstract
Pulmonary hypertension is recognized as a leading cause of morbidity and mortality in patients with sickle cell disease (SCD). We now report benchtop phenotyping from the explanted lungs of the first successful lung transplant in SCD. Pulmonary artery smooth muscle cells (PASMCs) cultured from the explanted lungs were analyzed for proliferate capacity, superoxide (O2 (•-)) production, and changes in key pulmonary arterial hypertension (PAH)-associated molecules and compared with non-PAH PASMCs. Upregulation of several pathologic processes persisted in culture in SCD lung PASMCs in spite of cell passage. SCD lung PASMCs showed growth factor- and serum-independent proliferation, upregulation of matrix genes, and increased O2 (•-) production compared with control cells. Histologic analysis of SCD-associated PAH arteries demonstrated increased and ectopically located extracellular matrix deposition and degradation of elastin fibers. Biomechanical analysis of these vessels confirmed increased arterial stiffening and loss of elasticity. Functional analysis of distal fifth-order pulmonary arteries from these lungs demonstrated increased vasoconstriction to an α1-adrenergic receptor agonist and concurrent loss of both endothelial-dependent and endothelial-independent vasodilation compared with normal pulmonary arteries. This is the first study to evaluate the molecular, cellular, functional, and mechanical changes in end-stage SCD-associated PAH.
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Affiliation(s)
- Natasha M Rogers
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Mingyi Yao
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - John Sembrat
- Heart and Vascular Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - M Patricia George
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA ; Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Heather Knupp
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Mark Ross
- Center for Biologic Imaging, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Maryam Sharifi-Sanjani
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jadranka Milosevic
- Dorothy P. and Richard P. Simmons Center for Interstitial Lung Disease, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Claudette St Croix
- Center for Biologic Imaging, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Revathi Rajkumar
- Heart and Vascular Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Maria G Frid
- Department of Pediatrics and Cardiovascular Pulmonary Research, University of Colorado, Denver, Colorado, USA
| | - Kendall S Hunter
- Department of Pediatrics and Cardiovascular Pulmonary Research, University of Colorado, Denver, Colorado, USA ; Department of Bioengineering, University of Colorado, Denver, Colorado, USA
| | - Luciano Mazzaro
- Department of Bioengineering, University of Colorado, Denver, Colorado, USA
| | - Enrico M Novelli
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kurt R Stenmark
- Department of Pediatrics and Cardiovascular Pulmonary Research, University of Colorado, Denver, Colorado, USA
| | - Mark T Gladwin
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA ; Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Ferhaan Ahmad
- Heart and Vascular Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Hunter C Champion
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA ; Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jeffrey S Isenberg
- Vascular Medicine Institute of the University of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA ; Division of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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16
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Pang L, Qi J, Gao Y, Jin H, Du J. Adrenomedullin alleviates pulmonary artery collagen accumulation in rats with pulmonary hypertension induced by high blood flow. Peptides 2014; 54:101-7. [PMID: 24480725 DOI: 10.1016/j.peptides.2014.01.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 01/08/2014] [Accepted: 01/08/2014] [Indexed: 01/31/2023]
Abstract
Collagen accumulation is one of the important pathologic changes in the development of pulmonary hypertension. Previous research showed that adrenomedullin (ADM) mitigates the development of pulmonary hypertension. The present study explored the role of ADM in the development of pulmonary artery collagen accumulation induced by high pulmonary blood flow, by investigating the effect of ADM [1.5 μg/(kg h)] subcutaneously administered by mini-osmotic pump on pulmonary hemodynamics, pulmonary vascular structure and pulmonary artery collagen accumulation and synthesis in rats with high pulmonary blood flow induced by aortocaval shunting. The results showed that ADM significantly decreased mean pulmonary artery pressure (mPAP) and the ratio of right ventricular mass to left ventricular plus septal mass [RV/(LV+SP)], attenuated the muscularization of small pulmonary vessels and relative medial thickness (RMT) of pulmonary arteries in rats with high pulmonary blood flow. Meanwhile, ADM ameliorated pulmonary artery collagen deposition represented by a decrease in lung tissue hydroxyproline, collagens I and III content and pulmonary artery collagens I and III expression, reduced collagen synthesis represented by a decrease in lung tissue procollagens I and III mRNA expression. The results suggest that ADM plays a protective role in the development of pulmonary hypertension induced by high blood flow, by inhibiting pulmonary procollagen synthesis and alleviating pulmonary artery collagen accumulation.
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Affiliation(s)
- Lulu Pang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China.
| | - Jianguang Qi
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China.
| | - Yang Gao
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Hongfang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Junbao Du
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
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17
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Lee SH, Do SI, Kim HS. Hyperoxia accelerates progression of hepatic fibrosis by up-regulation of transforming growth factor-β expression. World J Gastroenterol 2014; 20:3011-3017. [PMID: 24659892 PMCID: PMC3961973 DOI: 10.3748/wjg.v20.i11.3011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 11/10/2013] [Accepted: 01/06/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of hypoxia or hyperoxia on the progression of hepatic fibrosis and to examine the role of transforming growth factor-β (TGF-β) in the livers of rats exposed to hypoxic or hyperoxic conditions.
METHODS: Male Sprague-Dawley rats were injected intraperitoneally with thioacetamide to induce hepatic fibrosis and were randomly divided into a hypoxia group, a hyperoxia group and an untreated control group. Ten rats in the hypoxia group were exposed to an altitude of 20000 ft for 1 h/d during 7 wk. Ten rats in the hyperoxia group were exposed to a water depth of 20 m with 100% oxygen supply for 1 h/d during 7 wk. We evaluated the degree of hepatic fibrosis using Masson trichrome stain and examined the expression level of hepatic TGF-β mRNA using quantitative real-time reverse transcriptase-polymerase chain reaction analysis.
RESULTS: Eight of 10 rats exposed to hypoxia showed diffuse and confluent fibrosis with the formation of structurally abnormal parenchymal nodules involving the entire liver, consistent with hepatic cirrhosis. Nine of 10 rats exposed to hyperoxia also demonstrated obvious histological findings of hepatic cirrhosis identical to those in hypoxic rat livers. In contrast, 8 of 10 untreated rats had periportal or septal fibrosis only. The frequency of hepatic cirrhosis in hypoxic rats (P = 0.009) and hyperoxic rats (P = 0.003) was significantly higher than that in untreated rats. In addition, hepatic TGF-β mRNA levels in hyperoxic rats were significantly higher than those in untreated rats. The mean value of the normalized TGF-β mRNA/β-actin expression ratio in the hyperoxic rats was 1.9-fold higher than that in the untreated rats (P = 0.027).
CONCLUSION: We demonstrated that both hypoxia and hyperoxia accelerated the progression of hepatic fibrosis in rats. Significant up-regulation of hepatic TGF-β in hyperoxic rats suggests that TGF-β is involved in the acceleration of hepatic fibrosis under hyperoxic conditions.
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18
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Schreier D, Hacker T, Song G, Chesler N. The role of collagen synthesis in ventricular and vascular adaptation to hypoxic pulmonary hypertension. J Biomech Eng 2013; 135:021018. [PMID: 23445063 DOI: 10.1115/1.4023480] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pulmonary arterial hypertension (PAH) is a rapidly fatal disease in which mortality is typically due to right ventricular (RV) failure. An excellent predictor of mortality in PAH is proximal pulmonary artery stiffening, which is mediated by collagen accumulation in hypoxia-induced pulmonary hypertension (HPH) in mice. We sought to investigate the impact of limiting vascular and ventricular collagen accumulation on RV function and the hemodynamic coupling efficiency between the RV and pulmonary vasculature. Inbred mice were exposed to chronic hypoxia for 10 days with either no treatment (HPH) or with treatment with a proline analog that impairs collagen synthesis (CHOP-PEG; HPH + CP). Both groups were compared to control mice (CTL) exposed only to normoxia (no treatment). An admittance catheter was used to measure pressure-volume loops at baseline and during vena cava occlusion, with mice ventilated with either room air or 8% oxygen, from which pulmonary hemodynamics, RV function, and ventricular-vascular coupling efficiency (ηvvc) were calculated. Proline analog treatment limited increases in RV afterload (neither effective arterial elastance Ea nor total pulmonary vascular resistance significantly increased compared to CTL with CHOP-PEG), limited the development of pulmonary hypertension (CHOP-PEG reduced right ventricular systolic pressure by 10% compared to HPH, p < 0.05), and limited RV hypertrophy (CHOP-PEG reduced RV mass by 18% compared to HPH, p < 0.005). In an acutely hypoxic state, treatment improved RV function (CHOP-PEG increased end-systolic elastance Ees by 43%, p < 0.05) and maintained ηvvc at control, room air levels. CHOP-PEG also decreased lung collagen content by 12% measured biochemically compared to HPH (p < 0.01), with differences evident in large and small pulmonary arteries by histology. Our results demonstrate that preventing new collagen synthesis limits pulmonary hypertension development by reducing collagen accumulation in the pulmonary arteries that affect RV afterload. In particular, the proline analog limited structural and functional changes in distal pulmonary arteries in this model of early and somewhat mild pulmonary hypertension. We conclude that collagen plays an important role in small pulmonary artery remodeling and, thereby, affects RV structure and function changes induced by chronic hypoxia.
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Affiliation(s)
- David Schreier
- Department of Biomedical Engineering, University of Wisconsin, 2145 ECB, 1550 Engineering Drive, Madison, WI 53706, USA
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19
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Wang Z, Chesler NC. Pulmonary vascular mechanics: important contributors to the increased right ventricular afterload of pulmonary hypertension. Exp Physiol 2013; 98:1267-73. [PMID: 23666792 DOI: 10.1113/expphysiol.2012.069096] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Chronic hypoxia causes pulmonary vasoconstriction and vascular remodelling, which lead to hypoxic pulmonary hypertension (HPH). Hypoxic pulmonary hypertension is associated with living at high altitudes and is a complication of many lung diseases, including chronic obstructive pulmonary disease, cystic fibrosis and obstructive sleep apnoea. Pulmonary vascular changes that occur with HPH include stiffening and narrowing of the pulmonary arteries that appear to involve all vascular cell types and sublayers of the arterial wall. Right ventricular (RV) changes that occur with HPH include RV hypertrophy and RV fibrosis, often with preserved systolic and diastolic function and ventricular-vascular coupling efficiency. Both vascular stiffening and vascular narrowing are important contributors to RV afterload via increases in oscillatory and steady ventricular work, respectively. The increased blood viscosity that occurs in HPH can be dramatic and is another important contributor to RV afterload. However, the viscosity, vascular mechanics and ventricular changes that occur with HPH are all reversible. Furthermore, even with continued hypoxia the vascular remodelling does not progress to the obliterative, plexiform lesions that are seen clinically in severe pulmonary hypertension. In animal models, the RV changes appear adaptive, not maladaptive. In summary, HPH-induced vascular mechanical changes affect ventricular function, but both are adaptive and reversible, which differentiates HPH from severe pulmonary hypertension. The mechanisms of adaptation and reversibility may provide useful insight into therapeutic targets for the clinical disease state.
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Affiliation(s)
- Zhijie Wang
- Department of Biomedical Engineering, University of Wisconsin–Madison, Madison, WI 53706, USA
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20
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Hypoxia potentiates allergen induction of HIF-1α, chemokines, airway inflammation, TGF-β1, and airway remodeling in a mouse model. Clin Immunol 2013; 147:27-37. [PMID: 23499929 DOI: 10.1016/j.clim.2013.02.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/11/2013] [Accepted: 02/12/2013] [Indexed: 02/08/2023]
Abstract
Whether hypoxia contributes to airway inflammation and remodeling in asthma is unknown. In this study we used mice exposed to a hypoxic environment during allergen challenge (simulating hypoxia during an asthma exacerbation) to investigate the contribution of hypoxia to airway inflammation and remodeling. Although neither hypoxia alone, nor OVA allergen alone, induced significant neutrophil influx into the lung, the combination of OVA and hypoxia induced a synergistic 27 fold increase in peribronchial neutrophils, enhanced expression of HIF-1α and one of its target genes, the CXC-family neutrophil chemokine KC. The combination of hypoxia and OVA allergen increased eotaxin-1, peribronchial eosinophils, lung TGB-β1 expression, and indices of airway remodeling (fibrosis and smooth muscle) compared to either stimulus alone. As hypoxia is present in >90% of severe asthma exacerbations, these findings underscore the potential of hypoxia to potentiate the airway inflammatory response, remodeling, and accelerate the decline of lung function in asthma exacerbations.
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21
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Abstract
Genetically modified mouse models have unparalleled power to determine the mechanisms behind different processes involved in the molecular and physiologic etiology of various classes of human pulmonary hypertension (PH). Processes known to be involved in PH for which there are extensive mouse models available include the following: (1) Regulation of vascular tone through secreted vasoactive factors; (2) regulation of vascular tone through potassium and calcium channels; (3) regulation of vascular remodeling through alteration in metabolic processes, either through alteration in substrate usage or through circulating factors; (4) spontaneous vascular remodeling either before or after development of elevated pulmonary pressures; and (5) models in which changes in tone and remodeling are primarily driven by inflammation. PH development in mice is of necessity faster and with different physiologic ramifications than found in human disease, and so mice make poor models of natural history of PH. However, transgenic mouse models are a perfect tool for studying the processes involved in pulmonary vascular function and disease, and can effectively be used to test interventions designed against particular molecular pathways and processes involved in disease.
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Affiliation(s)
- Mita Das
- Department of Internal Medicine, University of Arkansas Medical Sciences, Little Rock, Arkansas, USA
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22
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Wang Z, Lakes RS, Eickhoff JC, Chesler NC. Effects of collagen deposition on passive and active mechanical properties of large pulmonary arteries in hypoxic pulmonary hypertension. Biomech Model Mechanobiol 2013; 12:1115-25. [PMID: 23377784 DOI: 10.1007/s10237-012-0467-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 12/20/2012] [Indexed: 02/03/2023]
Abstract
Proximal pulmonary artery (PA) stiffening is a strong predictor of mortality in pulmonary hypertension. Collagen accumulation is mainly responsible for PA stiffening in hypoxia-induced pulmonary hypertension (HPH) in mouse models. We hypothesized that collagen cross-linking and the type I isoform are the main determinants of large PA mechanical changes during HPH, which we tested by exposing mice that resist type I collagen degradation (Col1a1[Formula: see text] and littermate controls (Col1a1[Formula: see text] to hypoxia for 10 days with or without [Formula: see text]-aminopropionitrile (BAPN) treatment to prevent cross-link formation. Static and dynamic mechanical tests were performed on isolated PAs with smooth muscle cells (SMC) in passive and active states. Percentages of type I and III collagen were quantified by histology; total collagen content and cross-linking were measured biochemically. In the SMC passive state, for both genotypes, hypoxia tended to increase PA stiffness and damping capacity, and BAPN treatment limited these increases. These changes were correlated with collagen cross-linking ([Formula: see text]). In the SMC active state, hypoxia increased PA dynamic stiffness and BAPN had no effect in Col1a1[Formula: see text] mice ([Formula: see text]). PA stiffness did not change in Col1a1[Formula: see text] mice. Similarly, damping capacity did not change for either genotype. Type I collagen accumulated more in Col1a1[Formula: see text] mice, whereas type III collagen increased more in Col1a1[Formula: see text] mice during HPH. In summary, PA passive mechanical properties (both static and dynamic) are related to collagen cross-linking. Type I collagen turnover is critical to large PA remodeling during HPH when collagen metabolism is not mutated and type III collagen may serve as a reserve.
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Affiliation(s)
- Zhijie Wang
- Department of Biomedical Engineering, University of Wisconsin at Madison, 2145 ECB; 1550 Engineering Drive, Madison, WI, 53706-1609, USA
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23
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Chronic and intermittent hypoxia differentially regulate left ventricular inflammatory and extracellular matrix responses. Hypertens Res 2012; 35:811-8. [PMID: 22495609 PMCID: PMC3419973 DOI: 10.1038/hr.2012.32] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
We evaluated the left ventricle (LV) response to hypoxia by comparing male Sprague Dawley rats exposed for 7 days to normoxia (control; n=18), chronic sustained hypoxia (CSH; n=12) and chronic intermittent hypoxia (CIH; n=12). Out of the 168 inflammatory, extracellular matrix and adhesion molecule genes evaluated, Ltb, Cdh4, Col5a1, Ecm1, MMP-11 and TIMP-2 increased in the LV (range: 87–138%), whereas Tnfrsf1a decreased 27%, indicating an increase in inflammatory status with CSH (all P<0.05). CIH decreased Ltb, Spp1 and Ccl5 levels, indicating reduced inflammatory status. While Laminin β2 gene levels increased 123%, MMP-9 and fibronectin gene levels both decreased 74% in CIH (all P<0.05). Right ventricle/body weight ratios increased in CSH (1.1±0.1 g g−1) compared with control (0.7±0.1 g g−1) and CIH (0.8±0.1 g g−1; both P<0.05). Lung to body weight increased in CSH, while LV/body weight ratios were similar among all three groups. With CIH, myocyte cross sectional areas increased 25% and perivascular fibrosis increased 100% (both P<0.05). Gene changes were independent of global changes and were validated by protein levels. MMP-9 protein levels decreased 94% and fibronectin protein levels decreased 42% in CIH (both P<0.05). Consistent with a decreased inflammatory status, HIF-2α and eNOS protein levels were 36% and 44% decreased, respectively, in CIH (both P<0.05). In conclusion, our results indicate that following 7 days of hypoxia, inflammation increases in response to CSH and decreases in response to CIH. This report is the first to demonstrate specific and differential changes seen in the LV during chronic sustained and CIH.
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24
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Maxová H, Hezinová A, Vízek M. Disodium cromoglycate attenuates hypoxia induced enlargement of end-expiratory lung volume in rats. Physiol Res 2011; 60:831-4. [PMID: 22106819 DOI: 10.33549/physiolres.932200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Mechanism responsible for the enlargement of end-expiratory lung volume (EELV) induced by chronic hypoxia remains unclear. The fact that the increase in EELV persists after return to normoxia suggests involvement of morphological changes. Because hypoxia has been also shown to activate lung mast cells, we speculated that they could play in the mechanism increasing EELV similar role as in vessel remodeling in hypoxic pulmonary hypertension (HPH). We, therefore, tested an effect of mast cells degranulation blocker disodium cromoglycate (DSCG) on hypoxia induced EELV enlargement. Ventilatory parameters, EELV and right to left heart weight ratio (RV/LV+S) were measured in male Wistar rats. The experimental group (H+DSCG) was exposed to 3 weeks of normobaric hypoxia and treated with DSCG during the first four days of hypoxia, control group was exposed to hypoxia only (H), two others were kept in normoxia as non-treated (N) and treated (N+DSCG) groups. DSCG treatment significantly attenuated the EELV enlargement (H+DSCG = 6.1+/-0.8; H = 9.2+/-0.9; ml +/-SE) together with the increase in minute ventilation (H + DSCG = 190+/-8; H = 273 +/- 10; ml/min +/- SE) and RV/LV + S (H + DSCG = 0.39 +/- 0.03; H = 0.50 +/- 0.06).
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Affiliation(s)
- H Maxová
- Department of Pathophysiology, Second Faculty of Medicine, Charles University in Prague, Praha, Czech Republic.
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25
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Umesh A, Paudel O, Cao YN, Myers AC, Sham JSK. Alteration of pulmonary artery integrin levels in chronic hypoxia and monocrotaline-induced pulmonary hypertension. J Vasc Res 2011; 48:525-37. [PMID: 21829038 DOI: 10.1159/000329593] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Accepted: 05/20/2011] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Pulmonary hypertension is associated with vascular remodeling and increased extracellular matrix (ECM) deposition. While the contribution of ECM in vascular remodeling is well documented, the roles played by their receptors, integrins, in pulmonary hypertension have received little attention. Here we characterized the changes of integrin expression in endothelium-denuded pulmonary arteries (PAs) and aorta of chronic hypoxia as well as monocrotaline-treated rats. METHODS AND RESULTS Immunoblot showed increased α(1)-, α(8)- and α(v)-integrins, and decreased α(5)-integrin levels in PAs of both models. β(1)- and β(3)-integrins were reduced in PAs of chronic hypoxia and monocrotaline-treated rats, respectively. Integrin expression in aorta was minimally affected. Differential expression of α(1)- and α(5)-integrins induced by chronic hypoxia was further examined. Immunostaining showed that they were expressed on the surface of PA smooth muscle cells (PASMCs), and their distribution was unaltered by chronic hypoxia. Phosphorylation of focal adhesion kinase was augmented in PAs of chronic hypoxia rats, and in chronic hypoxia PASMCs cultured on the α(1)-ligand collagen IV. Moreover, α(1)-integrin binding hexapeptide GRGDTP elicited an enhanced Ca(2+) response, whereas the response to α(5)-integrin binding peptide GRGDNP was reduced in CH-PASMCs. CONCLUSION Integrins in PASMCs are differentially regulated in pulmonary hypertension, and the dynamic integrin-ECM interactions may contribute to the vascular remodeling accompanying disease progression.
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Affiliation(s)
- Anita Umesh
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
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26
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Hunter KS, Lammers SR, Shandas R. Pulmonary vascular stiffness: measurement, modeling, and implications in normal and hypertensive pulmonary circulations. Compr Physiol 2011; 1:1413-35. [PMID: 23733649 PMCID: PMC4113421 DOI: 10.1002/cphy.c100005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This article introduces the concept of pulmonary vascular stiffness, discusses its increasingly recognized importance as a diagnostic marker in the evaluation of pulmonary vascular disease, and describes methods to measure and model it clinically, experimentally, and computationally. It begins with a description of systems-level methods to evaluate pulmonary vascular compliance and recent clinical efforts in applying such techniques to better predict patient outcomes in pulmonary arterial hypertension. It then progresses from the systems-level to the local level, discusses proposed methods by which upstream pulmonary vessels increase in stiffness, introduces concepts around vascular mechanics, and concludes by describing recent work incorporating advanced numerical methods to more thoroughly evaluate changes in local mechanical properties of pulmonary arteries.
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Affiliation(s)
- Kendall S. Hunter
- Department of Bioengineering, University of Colorado at Denver Anschutz Medical Campus (UCD-AMC), Aurora, Colorado
- Division of Cardiology, Department of Pediatrics, The Children’s Hospital of Denver, UCD-AMC, Aurora, Colorado
| | - Steven R. Lammers
- Department of Bioengineering, University of Colorado at Denver Anschutz Medical Campus (UCD-AMC), Aurora, Colorado
- Cardiovascular Pulmonary (CVP) Research Laboratory, UCD-AMC, Aurora, Colorado
| | - Robin Shandas
- Department of Bioengineering, University of Colorado at Denver Anschutz Medical Campus (UCD-AMC), Aurora, Colorado
- Division of Cardiology, Department of Pediatrics, The Children’s Hospital of Denver, UCD-AMC, Aurora, Colorado
- Department of Surgery, UCD-AMC, Aurora, Colorado
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Ko EA, Song MY, Donthamsetty R, Makino A, Yuan JXJ. Tension Measurement in Isolated Rat and Mouse Pulmonary Artery. ACTA ACUST UNITED AC 2011; 7:123-130. [PMID: 23175638 DOI: 10.1016/j.ddmod.2011.04.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Arterial vasoconstriction is an important physiological process in regulating blood pressure, and is involved in pathologies. The isolation of arteries from rats and mice, as well as the measurement of vascular tension in an ex vivo preparation, are important methods in studying the physiology of arteries and the pathophysiology associated with arterials. Three major methods to measure vascular tension are organ bath, wire myograph, and pressurized arterial myograph. The major method to measure vascular remodeling is by observing the zero-stress state of an artery.
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Affiliation(s)
- Eun A Ko
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL 60612
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28
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Vanderpool RR, Kim AR, Molthen R, Chesler NC. Effects of acute Rho kinase inhibition on chronic hypoxia-induced changes in proximal and distal pulmonary arterial structure and function. J Appl Physiol (1985) 2011; 110:188-98. [PMID: 21088209 PMCID: PMC3253002 DOI: 10.1152/japplphysiol.00533.2010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2010] [Accepted: 11/11/2010] [Indexed: 01/25/2023] Open
Abstract
Hypoxic pulmonary hypertension (HPH) is initially a disease of the small pulmonary arteries. Its severity is usually quantified by pulmonary vascular resistance (PVR). Acute Rho kinase inhibition has been found to reduce PVR toward control values in animal models, suggesting that persistent pulmonary vasoconstriction is the dominant mechanism for increased PVR. However, HPH may also cause proximal arterial changes, which are relevant to right ventricular (RV) afterload. RV afterload can be quantified by pulmonary vascular impedance, which is obtained via spectral analysis of pulsatile pressure-flow relationships. To determine the effects of HPH independent of persistent pulmonary vasoconstriction in proximal and distal arteries, we quantified pulsatile pressure-flow relationships before and after acute Rho kinase inhibition and measured pulmonary arterial structure with microcomputed tomography. In control lungs, Rho kinase inhibition decreased 0 Hz impedance (Z₀), which is equivalent to PVR, from 2.1 ± 0.4 to 1.5 ± 0.2 mmHg·min·ml⁻¹ (P < 0.05) and tended to increase characteristic impedance (Z(C)) from 0.21 ± 0.01 to 0.22 ± 0.01 mmHg·min·ml⁻¹. In HPH lungs, Rho kinase inhibition decreased Z₀ (P < 0.05) without affecting Z(C). Microcomputed tomography measurements performed on lungs after acute Rho kinase inhibition demonstrated that HPH significantly decreased the unstressed diameter of the main pulmonary artery (760 ± 60 vs. 650 ± 80 μm; P < 0.05), decreased right pulmonary artery compliance, and reduced the frequency of arteries of diameter 50-100 μm (both P < 0.05). These results demonstrate that acute Rho kinase inhibition reverses many but not all HPH-induced changes in distal pulmonary arteries but does not affect HPH-induced changes in the conduit arteries that impact RV afterload.
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Affiliation(s)
- Rebecca R Vanderpool
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, USA
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29
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Ooi CY, Wang Z, Tabima DM, Eickhoff JC, Chesler NC. The role of collagen in extralobar pulmonary artery stiffening in response to hypoxia-induced pulmonary hypertension. Am J Physiol Heart Circ Physiol 2010; 299:H1823-31. [PMID: 20852040 DOI: 10.1152/ajpheart.00493.2009] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypoxic pulmonary hypertension (HPH) causes extralobar pulmonary artery (PA) stiffening, which potentially impairs right ventricular systolic function. Changes in the extracellular matrix proteins collagen and elastin have been suggested to contribute to this arterial stiffening. We hypothesized that vascular collagen accumulation is a major cause of extralobar PA stiffening in HPH and tested our hypothesis with transgenic mice that synthesize collagen type I resistant to collagenase degradation (Col1a1(R/R)). These mice and littermate controls that have normal collagen degradation (Col1a1(+/+)) were exposed to hypoxia for 10 days; some were allowed to recover for 32 days. In vivo PA pressure and isolated PA mechanical properties and collagen and elastin content were measured for all groups. Vasoactive studies were also performed with U-46619, Y-27632, or calcium- and magnesium-free medium. Pulmonary hypertension occurred in both mouse strains due to chronic hypoxia and resolved with recovery. HPH caused significant PA mechanical changes in both mouse strains: circumferential stretch decreased, and mid-to-high-strain circumferential elastic modulus increased (P < 0.05 for both). Impaired collagen type I degradation prevented a return to baseline mechanical properties with recovery and, in fact, led to an increase in the low and mid-to-high-strain moduli compared with hypoxia (P < 0.05 for both). Significant changes in collagen content were found, which tended to follow changes in mid-to-high-strain elastic modulus. No significant changes in elastin content or vasoactivity were observed. Our results demonstrate that collagen content is important to extralobar PA stiffening caused by chronic hypoxia.
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Affiliation(s)
- Chen Yen Ooi
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706-1609, USA
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30
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van Vlimmeren MAA, Driessen-Mol A, van den Broek M, Bouten CVC, Baaijens FPT. Controlling matrix formation and cross-linking by hypoxia in cardiovascular tissue engineering. J Appl Physiol (1985) 2010; 109:1483-91. [PMID: 20847132 DOI: 10.1152/japplphysiol.00571.2010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In vivo functionality of cardiovascular tissue engineered constructs requires in vitro control of tissue development to obtain a well developed extracellular matrix (ECM). We hypothesize that ECM formation and maturation is stimulated by culturing at low oxygen concentrations. Gene expression levels of monolayers of human vascular-derived myofibroblasts, exposed to 7, 4, 2, 1, and 0.5% O(2) (n = 9 per group) for 24 h, were measured for vascular endothelial growth factor (VEGF), procollagen α1(I) and α1(III), elastin, and cross-link enzymes lysyl oxidase (LOX) and lysyl hydroxylase 2 (LH2). After 4 days of exposure to 7, 2, and 0.5% O(2) (n = 3 per group), protein synthesis was evaluated. All analyses were compared with control cultures at 21% O(2). Human myofibroblasts turned to hypoxia-driven gene expression, indicated by VEGF expression, at oxygen concentrations of 4% and lower. Gene expression levels of procollagen α1(I) and α1(III) increased to 138 ± 26 and 143 ± 19%, respectively, for all oxygen concentrations below 4%. At 2% O(2), LH2 and LOX gene expression levels were higher than control cultures (340 ± 53 and 136 ± 29%, respectively), and these levels increased even further with decreasing oxygen concentrations (611 ± 176 and 228 ± 45%, respectively, at 0.5% O(2)). Elastin gene expression levels remained unaffected. Collagen synthesis and LH2 protein levels increased at oxygen concentrations of 2% and lower. Oxygen concentrations below 4% induce enhanced ECM production by human myofibroblasts. Implementation of these results in cardiovascular tissue engineering approaches enables in vitro control of tissue development.
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Affiliation(s)
- Marijke A A van Vlimmeren
- Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
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Stenmark KR, Meyrick B, Galie N, Mooi WJ, McMurtry IF. Animal models of pulmonary arterial hypertension: the hope for etiological discovery and pharmacological cure. Am J Physiol Lung Cell Mol Physiol 2009; 297:L1013-32. [DOI: 10.1152/ajplung.00217.2009] [Citation(s) in RCA: 565] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
At present, six groups of chronic pulmonary hypertension (PH) are described. Among these, group 1 (and 1′) comprises a group of diverse diseases termed pulmonary arterial hypertension (PAH) that have several pathophysiological, histological, and prognostic features in common. PAH is a particularly severe and progressive form of PH that frequently leads to right heart failure and premature death. The diagnosis of PAH must include a series of defined clinical parameters, which extend beyond mere elevations in pulmonary arterial pressures and include precapillary PH, pulmonary hypertensive arteriopathy (usually with plexiform lesions), slow clinical onset (months or years), and a chronic time course (years) characterized by progressive deterioration. What appears to distinguish PAH from other forms of PH is the severity of the arteriopathy observed, the defining characteristic of which is “plexogenic arteriopathy.” The pathogenesis of this arteriopathy remains unclear despite intense investigation in a variety of animal model systems. The most commonly used animal models (“classic” models) are rodents exposed to either hypoxia or monocrotaline. Newer models, which involve modification of classic approaches, have been developed that exhibit more severe PH and vascular lesions, which include neointimal proliferation and occlusion of small vessels. In addition, genetically manipulated mice have been generated that have provided insight into the role of specific molecules in the pulmonary hypertensive process. Unfortunately, at present, there is no perfect preclinical model that completely recapitulates human PAH. All models, however, have provided and will continue to provide invaluable insight into the numerous pathways that contribute to the development and maintenance of PH. Use of both classic and newly developed animal models will allow continued rigorous testing of new hypotheses regarding pathogenesis and treatment. This review highlights progress that has been made in animal modeling of this important human condition.
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