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Santos EW, Khatoon S, Di Mise A, Zheng YM, Wang YX. Mitochondrial Dynamics in Pulmonary Hypertension. Biomedicines 2023; 12:53. [PMID: 38255160 PMCID: PMC10813473 DOI: 10.3390/biomedicines12010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/12/2023] [Accepted: 12/19/2023] [Indexed: 01/24/2024] Open
Abstract
Mitochondria are essential organelles for energy production, calcium homeostasis, redox signaling, and other cellular responses involved in pulmonary vascular biology and disease processes. Mitochondrial homeostasis depends on a balance in mitochondrial fusion and fission (dynamics). Mitochondrial dynamics are regulated by a viable circadian clock. Hypoxia and nicotine exposure can cause dysfunctions in mitochondrial dynamics, increases in mitochondrial reactive oxygen species generation and calcium concentration, and decreases in ATP production. These mitochondrial changes contribute significantly to pulmonary vascular oxidative stress, inflammatory responses, contractile dysfunction, pathologic remodeling, and eventually pulmonary hypertension. In this review article, therefore, we primarily summarize recent advances in basic, translational, and clinical studies of circadian roles in mitochondrial metabolism in the pulmonary vasculature. This knowledge may not only be crucial to fully understanding the development of pulmonary hypertension, but also greatly help to create new therapeutic strategies for treating this devastating disease and other related pulmonary disorders.
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Affiliation(s)
- Ed Wilson Santos
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208, USA; (E.W.S.); (S.K.); (A.D.M.)
| | - Subika Khatoon
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208, USA; (E.W.S.); (S.K.); (A.D.M.)
| | - Annarita Di Mise
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208, USA; (E.W.S.); (S.K.); (A.D.M.)
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via Orabona, 4, 70125 Bari, Italy
| | - Yun-Min Zheng
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208, USA; (E.W.S.); (S.K.); (A.D.M.)
| | - Yong-Xiao Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY 12208, USA; (E.W.S.); (S.K.); (A.D.M.)
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Gurhan H, Barnes F. Impact of weak radiofrequency and static magnetic fields on key signaling molecules, intracellular pH, membrane potential, and cell growth in HT-1080 fibrosarcoma cells. Sci Rep 2023; 13:14223. [PMID: 37648766 PMCID: PMC10469173 DOI: 10.1038/s41598-023-41167-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/23/2023] [Indexed: 09/01/2023] Open
Abstract
There are substantial concerns that extended exposures to weak radiofrequency (RF) fields can lead to adverse health effects. In this study, HT-1080 fibrosarcoma cells were simultaneously exposed to a static magnetic flux density between 10 [Formula: see text] and 300 [Formula: see text] and RF magnetic fields with amplitudes ranging from 1 nT to 1.5 μT in the frequency range from 1.8 to 7.2 MHz for four days. Cell growth rates, intracellular pH, hydrogen peroxide, peroxynitrite, membrane potential and mitochondrial calcium were measured. Results were dependent on carrier frequency and the magnitude of the RF magnetic field, modulation frequencies and the background static magnetic field (SMF). Iron sulphur (Fe-S) clusters are essential for the generation of reactive oxygen species and reactive nitrogen species (ROS and RNS). We believe the observed changes are associated with hyperfine couplings between the chemically active electrons and nuclear spins. Controlling external magnetic fields may have important clinical implications on aging, cancer, arthritis, and Alzheimer's.
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Affiliation(s)
- Hakki Gurhan
- Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB #1B55, Boulder, CO, 80309, USA.
| | - Frank Barnes
- Department of Electrical, Computer and Energy Engineering, University of Colorado at Boulder, 425 UCB #1B55, Boulder, CO, 80309, USA
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Zhang W, Liu B, Wang Y, Zhang H, He L, Wang P, Dong M. Mitochondrial dysfunction in pulmonary arterial hypertension. Front Physiol 2022; 13:1079989. [PMID: 36589421 PMCID: PMC9795033 DOI: 10.3389/fphys.2022.1079989] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Accepted: 11/29/2022] [Indexed: 01/03/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is characterized by the increased pulmonary vascular resistance due to pulmonary vasoconstriction and vascular remodeling. PAH has high disability, high mortality and poor prognosis, which is becoming a more common global health issue. There is currently no drug that can permanently cure PAH patients. The pathogenesis of PAH is still not fully elucidated. However, the role of metabolic theory in the pathogenesis of PAH is becoming clearer, especially mitochondrial metabolism. With the deepening of mitochondrial researches in recent years, more and more studies have shown that the occurrence and development of PAH are closely related to mitochondrial dysfunction, including the tricarboxylic acid cycle, redox homeostasis, enhanced glycolysis, and increased reactive oxygen species production, calcium dysregulation, mitophagy, etc. This review will further elucidate the relationship between mitochondrial metabolism and pulmonary vasoconstriction and pulmonary vascular remodeling. It might be possible to explore more comprehensive and specific treatment strategies for PAH by understanding these mitochondrial metabolic mechanisms.
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Affiliation(s)
- Weiwei Zhang
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Bo Liu
- Department of Cardiovascular, Geratric Diseases Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Yazhou Wang
- Department of Cardiothoracic, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Hengli Zhang
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Lang He
- Department of Oncology, Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital (The Second Clinical Medical College Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
| | - Pan Wang
- Department of Critical Care Medicine, The Traditional Chinese Medicine Hospital of Wenjiang District, Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
| | - Mingqing Dong
- Center for Medicine Research and Translation, Chengdu Fifth People’s Hospital (The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China,Correspondence: Mingqing Dong, ; Lang He, ; Pan Wang,
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Truong L, Zheng YM, Wang YX. The Potential Important Role of Mitochondrial Rieske Iron–Sulfur Protein as a Novel Therapeutic Target for Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease. Biomedicines 2022; 10:biomedicines10050957. [PMID: 35625694 PMCID: PMC9138741 DOI: 10.3390/biomedicines10050957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/19/2022] [Accepted: 04/19/2022] [Indexed: 02/01/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, which is often due to pulmonary hypertension (PH). The underlying molecular mechanisms are poorly understood, and current medications are neither specific nor always effective. In this review, we highlight the recent findings on the roles of altered mitochondrial bioenergetics in PH in COPD. We also discuss the central role of mitochondrial reactive oxygen species (ROS) generation mediated by Rieske iron–sulfur protein (RISP) and review the contributions of RISP-dependent DNA damage and NF-κB-associated inflammatory signaling. Finally, the potential importance of mitochondrial RISP and its associated molecules as novel therapeutic targets for PH in COPD are meticulously discussed.
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Affiliation(s)
| | | | - Yong-Xiao Wang
- Correspondence: ; Tel.: +1-(518)-262-9506; Fax: +1-(518)-262-8101
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Qi H, Li ZC, Wang SM, Wu L, Xu F, Liu ZL, Li X, Wang JZ. Tristability in mitochondrial permeability transition pore opening. CHAOS (WOODBURY, N.Y.) 2021; 31:123108. [PMID: 34972328 DOI: 10.1063/5.0065400] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 11/09/2021] [Indexed: 06/14/2023]
Abstract
Mitochondrial permeability transition pore (PTP), a key regulator of cell life and death processes, is triggered by calcium ions (Ca2+) and potentiated by reactive oxygen species (ROS). Although the two modes of PTP opening, i.e., transient and persistent, have been identified for a long time, its dynamical mechanism is still not fully understood. To test a proposed hypothesis that PTP opening acts as a tristable switch, which is characterized by low, medium, and high open probability, we develop a three-variable model that focused on PTP opening caused by Ca2+ and ROS. For the system reduced to two differential equations for Ca2+ and ROS, both the stability analysis and the potential landscape feature that it exhibits tristability under standard parameters. For the full system, the bifurcation analysis suggests that it can achieve tristability over a wide range of input parameters. Furthermore, parameter sensitivity analysis demonstrates that the existence of tristability is a robust property. In addition, we show how the deterministic tristable property can be understood within a stochastic framework, which also explains the PTP dynamics at the level of a single channel. Overall, this study may yield valuable insights into the intricate regulatory mechanism of PTP opening.
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Affiliation(s)
- Hong Qi
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China
| | - Zhi-Chao Li
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China
| | - Shi-Miao Wang
- School of Mathematical Sciences, Shanxi University, Taiyuan 030006, China
| | - Lin Wu
- School of Mathematical Sciences, Shanxi University, Taiyuan 030006, China
| | - Fei Xu
- Department of Physics and Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China
| | - Zhi-Long Liu
- Department of Physics and Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China
| | - Xiang Li
- Department of Physics and Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China
| | - Jia-Zeng Wang
- Department of Mathematics, Beijing Technology and Business University, Beijing 100048, China
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Santos JH. Mitochondria signaling to the epigenome: A novel role for an old organelle. Free Radic Biol Med 2021; 170:59-69. [PMID: 33271282 PMCID: PMC8166959 DOI: 10.1016/j.freeradbiomed.2020.11.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 12/23/2022]
Abstract
Epigenetic modifications influence gene expression programs ultimately dictating physiological outcomes. In the past decades, an increasing body of work has demonstrated that the enzymes that deposit and/or remove epigenetic marks on DNA or histones use metabolites as substrates or co-factors, rendering the epigenome sensitive to metabolic changes. In this context, acetyl-CoA and α-ketoglutarate have been recognized as critical for epigenetics, impinging on histone marks and nuclear DNA methylation patterns. Given that these metabolites are primarily generated in the mitochondria through the tricarboxylic acid cycle (TCA), the requirement of proper mitochondrial function for maintenance of the epigenetic landscape seems obvious. Nevertheless, it was not until recently when the epigenomic outcomes of mitochondrial dysfunction were tested, revealing mitochondria's far-reaching impact on epigenetics. This review will focus on data that directly tested the role of mitochondria on the epigenetic landscape, the mechanisms by which mitochondrial dysfunction may dysregulate the epigenome and gene expression, and their potential implications to health and disease.
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Affiliation(s)
- Janine Hertzog Santos
- National Toxicology Program Laboratory (NTPL), National Toxicology Program (NTP), National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park (RTP), NC, USA.
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Truong L, Zheng YM, Kandhi S, Wang YX. Overview on Interactive Role of Inflammation, Reactive Oxygen Species, and Calcium Signaling in Asthma, COPD, and Pulmonary Hypertension. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1304:147-164. [PMID: 34019268 DOI: 10.1007/978-3-030-68748-9_9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Inflammatory signaling is a major component in the development and progression of many lung diseases, including asthma, chronic obstructive pulmonary disorder (COPD), and pulmonary hypertension (PH). This chapter will provide a brief overview of asthma, COPD, and PH and how inflammation plays a vital role in these diseases. Specifically, we will discuss the role of reactive oxygen species (ROS) and Ca2+ signaling in inflammatory cellular responses and how these interactive signaling pathways mediate the development of asthma, COPD, and PH. We will also deliberate the key cellular responses of pulmonary arterial (PA) smooth muscle cells (SMCs) and airway SMCs (ASMCs) in these devastating lung diseases. The analysis of the importance of inflammation will shed light on the key questions remaining in this field and highlight molecular targets that are worth exploring. The crucial findings will not only demonstrate the novel roles of essential signaling molecules such as Rieske iron-sulfur protein and ryanodine receptor in the development and progress of asthma, COPD, and PH but also offer advanced insight for creating more effective and new therapeutic targets for these devastating inflammatory lung diseases.
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Affiliation(s)
- Lillian Truong
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Yun-Min Zheng
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA
| | - Sharath Kandhi
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA.
| | - Yong-Xiao Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA.
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Qi H, Xu G, Peng XL, Li X, Shuai J, Xu R. Roles of four feedback loops in mitochondrial permeability transition pore opening induced by Ca^{2+} and reactive oxygen species. Phys Rev E 2021; 102:062422. [PMID: 33466063 DOI: 10.1103/physreve.102.062422] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 12/04/2020] [Indexed: 11/07/2022]
Abstract
Transient or sustained permeability transition pore (PTP) opening is important in normal physiology or cell death, respectively. These are closely linked to Ca^{2+} and reactive oxygen species (ROS). The entry of Ca^{2+} into mitochondria regulates ROS production, and both Ca^{2+} and ROS trigger PTP opening. In addition to this feedforward loop, there exist four feedback loops in the Ca^{2+}-ROS-PTP system. ROS promotes Ca^{2+} entering (F1) and induces further ROS generation (F2), forming two positive feedback loops. PTP opening results in the efflux of Ca^{2+} (F3) and ROS (F4) from the mitochondria, forming two negative feedback loops. Owing to these complexities, we construct a mathematical model to dissect the roles of these feedback loops in the dynamics of PTP opening. The qualitative agreement between simulation results and recent experimental observations supports our hypothesis that under physiological conditions the PTP opens in an oscillatory state, while under pathological conditions it opens in a high steady state. We clarify that the negative feedback loops are responsible for producing oscillations, wherein F3 plays a more prominent role than F4; whereas the positive feedback loops are beneficial for maintaining oscillation robustness, wherein F1 has a more dominant role than F2. Furthermore, we manifest that the proper increase in negative feedback strength or decrease in positive feedback strength not only facilitates the occurrence of oscillations and thus protects the system against a high steady state, but also assists in lowering the oscillation peak. This study may provide potential therapeutic strategies in treating neurodegenerative diseases due to PTP dysfunction.
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Affiliation(s)
- Hong Qi
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China.,Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Shanxi University, Taiyuan 030006, China
| | - Guoping Xu
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China.,Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Shanxi University, Taiyuan 030006, China
| | - Xiao-Long Peng
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China.,Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Shanxi University, Taiyuan 030006, China
| | - Xiang Li
- Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, China.,State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, Xiamen University, Xiamen 361102, China
| | - Jianwei Shuai
- Department of Physics, College of Physical Science and Technology, Xiamen University, Xiamen 361005, China.,State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, Xiamen University, Xiamen 361102, China.,National Institute for Data Science in Health and Medicine, Xiamen University, Xiamen 361102, China
| | - Rui Xu
- Complex Systems Research Center, Shanxi University, Taiyuan 030006, China.,Shanxi Key Laboratory of Mathematical Techniques and Big Data Analysis on Disease Control and Prevention, Shanxi University, Taiyuan 030006, China
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9
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Yang Z, Song T, Truong L, Reyes-García J, Wang L, Zheng YM, Wang YX. Important Role of Sarcoplasmic Reticulum Ca 2+ Release via Ryanodine Receptor-2 Channel in Hypoxia-Induced Rieske Iron-Sulfur Protein-Mediated Mitochondrial Reactive Oxygen Species Generation in Pulmonary Artery Smooth Muscle Cells. Antioxid Redox Signal 2020; 32:447-462. [PMID: 31456413 PMCID: PMC6987675 DOI: 10.1089/ars.2018.7652] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Aims: It is known that mitochondrial reactive oxygen species generation ([ROS]m) causes the release of Ca2+via ryanodine receptor-2 (RyR2) on the sarcoplasmic reticulum (SR) in pulmonary artery smooth muscle cells (PASMCs), playing an essential role in hypoxic pulmonary vasoconstriction (HPV). In this study, we sought to determine whether hypoxia-induced RyR2-mediated Ca2+ release may in turn promote [ROS]m in PASMCs and the underlying signaling mechanism. Results: Our data reveal that application of caffeine or norepinephrine to induce Ca2+ release increased [ROS]m in PASMCs. Likewise, exogenous Ca2+ augmented ROS generation in isolated mitochondria and at complex III from PASMCs. Inhibition of mitochondrial Ca2+ uniporter (MCU) with Ru360 attenuated agonist-induced [ROS]m. Ru360 produced a similar inhibitory effect on hypoxia-induced [ROS]m. Rieske iron-sulfur protein (RISP) gene knockdown inhibited Ca2+- and caffeine-induced [ROS]m. Inhibition of RyR2 by tetracaine or RyR2 gene knockout suppressed hypoxia-induced [ROS]m as well. Innovation: In this article, we present convincing evidence that Ca2+ release following hypoxia or RyR simulation causes a significant increase in MCU, and the increased MCU subsequently RISP-dependent [ROS]m, which provides a positive feedback mechanism to enhance hypoxia-initiated [ROS]m in PASMCs. Conclusion: Our findings demonstrate that hypoxia-induced mitochondrial ROS-dependent SR RyR2-mediated Ca2+ release increases MCU and then RISP-dependent [ROS]m in PASMCs, which may make significant contributions to HPV and associated pulmonary hypertension.
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Affiliation(s)
- Zhao Yang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York.,Department of Respiratory Medicine, Suzhou Science & Technology Town Hospital, Suzhou, China
| | - Tengyao Song
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Lillian Truong
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Jorge Reyes-García
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Lan Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Yun-Min Zheng
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
| | - Yong-Xiao Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, New York
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Knock GA. NADPH oxidase in the vasculature: Expression, regulation and signalling pathways; role in normal cardiovascular physiology and its dysregulation in hypertension. Free Radic Biol Med 2019; 145:385-427. [PMID: 31585207 DOI: 10.1016/j.freeradbiomed.2019.09.029] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/29/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023]
Abstract
The last 20-25 years have seen an explosion of interest in the role of NADPH oxidase (NOX) in cardiovascular function and disease. In vascular smooth muscle and endothelium, NOX generates reactive oxygen species (ROS) that act as second messengers, contributing to the control of normal vascular function. NOX activity is altered in response to a variety of stimuli, including G-protein coupled receptor agonists, growth-factors, perfusion pressure, flow and hypoxia. NOX-derived ROS are involved in smooth muscle constriction, endothelium-dependent relaxation and smooth muscle growth, proliferation and migration, thus contributing to the fine-tuning of blood flow, arterial wall thickness and vascular resistance. Through reversible oxidative modification of target proteins, ROS regulate the activity of protein tyrosine phosphatases, kinases, G proteins, ion channels, cytoskeletal proteins and transcription factors. There is now considerable, but somewhat contradictory evidence that NOX contributes to the pathogenesis of hypertension through oxidative stress. Specific NOX isoforms have been implicated in endothelial dysfunction, hyper-contractility and vascular remodelling in various animal models of hypertension, pulmonary hypertension and pulmonary arterial hypertension, but also have potential protective effects, particularly NOX4. This review explores the multiplicity of NOX function in the healthy vasculature and the evidence for and against targeting NOX for antihypertensive therapy.
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Affiliation(s)
- Greg A Knock
- Dpt. of Inflammation Biology, School of Immunology & Microbial Sciences, Faculty of Life Sciences & Medicine, King's College London, UK.
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