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Ježek P, Dlasková A, Engstová H, Špačková J, Tauber J, Průchová P, Kloppel E, Mozheitova O, Jabůrek M. Mitochondrial Physiology of Cellular Redox Regulations. Physiol Res 2024; 73:S217-S242. [PMID: 38647168 DOI: 10.33549/physiolres.935269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024] Open
Abstract
Mitochondria (mt) represent the vital hub of the molecular physiology of the cell, being decision-makers in cell life/death and information signaling, including major redox regulations and redox signaling. Now we review recent advances in understanding mitochondrial redox homeostasis, including superoxide sources and H2O2 consumers, i.e., antioxidant mechanisms, as well as exemplar situations of physiological redox signaling, including the intramitochondrial one and mt-to-cytosol redox signals, which may be classified as acute and long-term signals. This review exemplifies the acute redox signals in hypoxic cell adaptation and upon insulin secretion in pancreatic beta-cells. We also show how metabolic changes under these circumstances are linked to mitochondrial cristae narrowing at higher intensity of ATP synthesis. Also, we will discuss major redox buffers, namely the peroxiredoxin system, which may also promote redox signaling. We will point out that pathological thresholds exist, specific for each cell type, above which the superoxide sources exceed regular antioxidant capacity and the concomitant harmful processes of oxidative stress subsequently initiate etiology of numerous diseases. The redox signaling may be impaired when sunk in such excessive pro-oxidative state.
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Affiliation(s)
- P Ježek
- Laboratory of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic.
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2
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Caggiano EG, Taniguchi CM. UCP2 and pancreatic cancer: conscious uncoupling for therapeutic effect. Cancer Metastasis Rev 2024; 43:777-794. [PMID: 38194152 PMCID: PMC11156755 DOI: 10.1007/s10555-023-10157-4] [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: 10/02/2023] [Accepted: 11/13/2023] [Indexed: 01/10/2024]
Abstract
Pancreatic cancer has an exaggerated dependence on mitochondrial metabolism, but methods to specifically target the mitochondria without off target effects in normal tissues that rely on these organelles is a significant challenge. The mitochondrial uncoupling protein 2 (UCP2) has potential as a cancer-specific drug target, and thus, we will review the known biology of UCP2 and discuss its potential role in the pathobiology and future therapy of pancreatic cancer.
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Affiliation(s)
- Emily G Caggiano
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
| | - Cullen M Taniguchi
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Department of Experimental Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Sivertsson E, Friederich-Persson M, Persson P, Nangaku M, Hansell P, Palm F. Thyroid hormone increases oxygen metabolism causing intrarenal tissue hypoxia; a pathway to kidney disease. PLoS One 2022; 17:e0264524. [PMID: 35239685 PMCID: PMC8893624 DOI: 10.1371/journal.pone.0264524] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 02/11/2022] [Indexed: 01/10/2023] Open
Abstract
The proposed mechanisms for the development of nephropathy are many, complex and often overlapping. Although recent literature strongly supports a role of kidney hypoxia as an independent pathway to nephropathy, the evidence remains inconclusive since the role of hypoxia is difficult to differentiate from confounding factors such as hyperglycemia, hypertension and oxidative stress. By increasing kidney oxygen consumption using triiodothyronine (T3) and, thus, avoiding these confounding factors, the aim of the present study was to investigate renal hypoxia per se as a causal pathway for the development of nephropathy. Healthy Sprague-Dawley rats were treated with T3 (10 μg/kg/day) and the angiotensin II AT1-receptor antagonist candesartan (1 mg/kg in drinking water) to eliminate effects of T3-induced renin release; and compared to a candesartan treated control group. After 7 weeks of treatment in vivo kidney function, oxygen metabolism and mitochondrial function were evaluated. T3 did not affect glomerular filtration rate or renal blood flow, but increased total kidney oxygen consumption resulting in cortical hypoxia. Nephropathy, demonstrated as albuminuria and tubulointerstitial fibrosis, developed in T3-treated animals. Mitochondria uncoupling mediated by uncoupling protein 2 and the adenosine nucleotide transporter was demonstrated as a mechanism causing the increased kidney oxygen consumption. Importantly, blood glucose levels, mean arterial blood pressure and oxidative stress levels were not affected by T3. In conclusion, the present study provides further evidence for increased kidney oxygen consumption causing intrarenal tissue hypoxia, as a causal pathway for development of nephropathy.
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Affiliation(s)
- Ebba Sivertsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Patrik Persson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | | | - Peter Hansell
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- * E-mail:
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4
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Regulation of Aging and Longevity by Ion Channels and Transporters. Cells 2022; 11:cells11071180. [PMID: 35406743 PMCID: PMC8997527 DOI: 10.3390/cells11071180] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/22/2022] [Accepted: 03/29/2022] [Indexed: 12/10/2022] Open
Abstract
Despite significant advances in our understanding of the mechanisms that underlie age-related physiological decline, our ability to translate these insights into actionable strategies to extend human healthspan has been limited. One of the major reasons for the existence of this barrier is that with a few important exceptions, many of the proteins that mediate aging have proven to be undruggable. The argument put forth here is that the amenability of ion channels and transporters to pharmacological manipulation could be leveraged to develop novel therapeutic strategies to combat aging. This review delves into the established roles for ion channels and transporters in the regulation of aging and longevity via their influence on membrane excitability, Ca2+ homeostasis, mitochondrial and endolysosomal function, and the transduction of sensory stimuli. The goal is to provide the reader with an understanding of emergent themes, and prompt further investigation into how the activities of ion channels and transporters sculpt the trajectories of cellular and organismal aging.
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Kirkman DL, Robinson AT, Rossman MJ, Seals DR, Edwards DG. Mitochondrial contributions to vascular endothelial dysfunction, arterial stiffness, and cardiovascular diseases. Am J Physiol Heart Circ Physiol 2021; 320:H2080-H2100. [PMID: 33834868 PMCID: PMC8163660 DOI: 10.1152/ajpheart.00917.2020] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/12/2021] [Accepted: 04/05/2021] [Indexed: 12/11/2022]
Abstract
Cardiovascular disease (CVD) affects one in three adults and remains the leading cause of death in America. Advancing age is a major risk factor for CVD. Recent plateaus in CVD-related mortality rates in high-income countries after decades of decline highlight a critical need to identify novel therapeutic targets and strategies to mitigate and manage the risk of CVD development and progression. Vascular dysfunction, characterized by endothelial dysfunction and large elastic artery stiffening, is independently associated with an increased CVD risk and incidence and is therefore an attractive target for CVD prevention and management. Vascular mitochondria have emerged as an important player in maintaining vascular homeostasis. As such, age- and disease-related impairments in mitochondrial function contribute to vascular dysfunction and consequent increases in CVD risk. This review outlines the role of mitochondria in vascular function and discusses the ramifications of mitochondrial dysfunction on vascular health in the setting of age and disease. The adverse vascular consequences of increased mitochondrial-derived reactive oxygen species, impaired mitochondrial quality control, and defective mitochondrial calcium cycling are emphasized, in particular. Current evidence for both lifestyle and pharmaceutical mitochondrial-targeted strategies to improve vascular function is also presented.
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Affiliation(s)
- Danielle L Kirkman
- Department of Kinesiology and Health Sciences, Virginia Commonwealth University, Richmond, Virginia
| | | | - Matthew J Rossman
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado
| | - Douglas R Seals
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado
| | - David G Edwards
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware
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Miyata Y, Mukae Y, Harada J, Matsuda T, Mitsunari K, Matsuo T, Ohba K, Sakai H. Pathological and Pharmacological Roles of Mitochondrial Reactive Oxygen Species in Malignant Neoplasms: Therapies Involving Chemical Compounds, Natural Products, and Photosensitizers. Molecules 2020; 25:E5252. [PMID: 33187225 PMCID: PMC7697499 DOI: 10.3390/molecules25225252] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/07/2020] [Accepted: 11/09/2020] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress plays an important role in cellular processes. Consequently, oxidative stress also affects etiology, progression, and response to therapeutics in various pathological conditions including malignant tumors. Oxidative stress and associated outcomes are often brought about by excessive generation of reactive oxygen species (ROS). Accumulation of ROS occurs due to dysregulation of homeostasis in an otherwise strictly controlled physiological condition. In fact, intracellular ROS levels are closely associated with the pathological status and outcome of numerous diseases. Notably, mitochondria are recognized as the critical regulator and primary source of ROS. Damage to mitochondria increases mitochondrial ROS (mROS) production, which leads to an increased level of total intracellular ROS. However, intracellular ROS level may not always reflect mROS levels, as ROS is not only produced by mitochondria but also by other organelles such as endoplasmic reticulum and peroxisomes. Thus, an evaluation of mROS would help us to recognize the biological and pathological characteristics and predictive markers of malignant tumors and develop efficient treatment strategies. In this review, we describe the pathological significance of mROS in malignant neoplasms. In particular, we show the association of mROS-related signaling in the molecular mechanisms of chemically synthesized and natural chemotherapeutic agents and photodynamic therapy.
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Affiliation(s)
- Yasuyoshi Miyata
- Department of Urology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan; (Y.M.); (J.H.); (T.M.); (K.M.); (T.M.); (K.O.); (H.S.)
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Otoupalova E, Smith S, Cheng G, Thannickal VJ. Oxidative Stress in Pulmonary Fibrosis. Compr Physiol 2020; 10:509-547. [PMID: 32163196 DOI: 10.1002/cphy.c190017] [Citation(s) in RCA: 132] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Oxidative stress has been linked to various disease states as well as physiological aging. The lungs are uniquely exposed to a highly oxidizing environment and have evolved several mechanisms to attenuate oxidative stress. Idiopathic pulmonary fibrosis (IPF) is a progressive age-related disorder that leads to architectural remodeling, impaired gas exchange, respiratory failure, and death. In this article, we discuss cellular sources of oxidant production, and antioxidant defenses, both enzymatic and nonenzymatic. We outline the current understanding of the pathogenesis of IPF and how oxidative stress contributes to fibrosis. Further, we link oxidative stress to the biology of aging that involves DNA damage responses, loss of proteostasis, and mitochondrial dysfunction. We discuss the recent findings on the role of reactive oxygen species (ROS) in specific fibrotic processes such as macrophage polarization and immunosenescence, alveolar epithelial cell apoptosis and senescence, myofibroblast differentiation and senescence, and alterations in the acellular extracellular matrix. Finally, we provide an overview of the current preclinical studies and clinical trials targeting oxidative stress in fibrosis and potential new strategies for future therapeutic interventions. © 2020 American Physiological Society. Compr Physiol 10:509-547, 2020.
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Affiliation(s)
- Eva Otoupalova
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sam Smith
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Guangjie Cheng
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Victor J Thannickal
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Chan JYH, Chan SHH. Differential impacts of brain stem oxidative stress and nitrosative stress on sympathetic vasomotor tone. Pharmacol Ther 2019; 201:120-136. [PMID: 31153955 DOI: 10.1016/j.pharmthera.2019.05.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/24/2019] [Indexed: 02/07/2023]
Abstract
Based on work-done in the rostral ventrolateral medulla (RVLM), this review presents four lessons learnt from studying the differential impacts of oxidative stress and nitrosative stress on sympathetic vasomotor tone and their clinical and therapeutic implications. The first lesson is that an increase in sympathetic vasomotor tone because of augmented oxidative stress in the RVLM is responsible for the generation of neurogenic hypertension. On the other hand, a shift from oxidative stress to nitrosative stress in the RVLM underpins the succession of increase to decrease in sympathetic vasomotor tone during the progression towards brain stem death. The second lesson is that, by having different cellular sources, regulatory mechanisms on synthesis and degradation, kinetics of chemical reactions, and downstream signaling pathways, reactive oxygen species and reactive nitrogen species should not be regarded as a singular moiety. The third lesson is that well-defined differential roles of oxidative stress and nitrosative stress with distinct regulatory mechanisms in the RVLM during neurogenic hypertension and brain stem death clearly denote that they are not interchangeable phenomena with unified cellular actions. Special attention must be paid to their beneficial or detrimental roles under a specific disease or a particular time-window of that disease. The fourth lesson is that, to be successful, future antioxidant therapies against neurogenic hypertension must take into consideration the much more complicated picture than that presented in this review on the generation, maintenance, regulation or modulation of the sympathetic vasomotor tone. The identification that the progression towards brain stem death entails a shift from oxidative stress to nitrosative stress in the RVLM may open a new vista for therapeutic intervention to slow down this transition.
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Affiliation(s)
- Julie Y H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
| | - Samuel H H Chan
- Institute for Translational Research in Biomedicine, Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
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Pharmacological strategies to lower crosstalk between nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and mitochondria. Biomed Pharmacother 2019; 111:1478-1498. [DOI: 10.1016/j.biopha.2018.11.128] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 11/23/2018] [Accepted: 11/27/2018] [Indexed: 02/07/2023] Open
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Zhou TC, Yang L, Liu YY, Qin Y, Li YP, Zhang L, Yang K, Yang Y. Polymorphisms in the Uncoupling Protein 2 Gene Are Associated with Diabetic Retinopathy in Han Chinese Patients with Type 2 Diabetes. Genet Test Mol Biomarkers 2018; 22:637-643. [PMID: 30359091 DOI: 10.1089/gtmb.2018.0115] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The uncoupling protein 2 (UCP2) gene plays an important role in the complications of type 2 diabetes (T2D). However, the association between variants in the UCP2 gene and diabetic retinopathy (DR) in Han Chinese T2D patients remains unclear. METHODS Two single-nucleotide polymorphisms (SNPs) [rs659366 (-866G/A) and a 45-bp insertion/deletion (I/D) in the 3'-UTR] in the UCP2 gene were genotyped in a study cohort of 209 T2D patients with DR and 199 T2D patients without DR by direct DNA sequencing. RESULTS Logistic regression analysis showed that the AA and GA genotypes of rs659366 were significantly associated with an increased risk for nonproliferative DR (NPDR) in the codominant model (corrected p-value <0.01) and the dominant model (corrected p-value = 0.006). Patients harboring the II and DI genotypes had a higher risk for PDR in the codominant model (corrected p-value = 0.011) and the dominant model (corrected p-value = 0.006), and the DI genotype showed a higher risk for NPDR in the dominant model (corrected p-value = 0.007) or codominant model (corrected p-value = 0.006). Further, haplotype analyses verified that the A-I haplotype is a risk haplotype for NPDR and PDR. CONCLUSION This study suggests that the UCP2 gene may be involved in the pathogenesis of NPDR and PDR in Han Chinese patients with T2D.
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Affiliation(s)
- Tai-Cheng Zhou
- 1 Central Laboratory, Department of Endocrinology, Second People's Hospital of Yunnan Province , Kunming, China
| | - Lei Yang
- 2 Nuclear Medicine Department, Second Affiliated Hospital of Kunming Medical University , Kunming, China
| | - Yong-Ying Liu
- 3 First Affiliated Hospital of Medical College, Shihezi University , Shihezi, China
| | - Yuan Qin
- 1 Central Laboratory, Department of Endocrinology, Second People's Hospital of Yunnan Province , Kunming, China
| | - Yi-Ping Li
- 1 Central Laboratory, Department of Endocrinology, Second People's Hospital of Yunnan Province , Kunming, China
| | - Liang Zhang
- 1 Central Laboratory, Department of Endocrinology, Second People's Hospital of Yunnan Province , Kunming, China
| | - Ke Yang
- 4 Cardiology Laboratory of Ruijin Hospital, Shanghai Jiaotong University School of Medicine , Shanghai, China
| | - Ying Yang
- 1 Central Laboratory, Department of Endocrinology, Second People's Hospital of Yunnan Province , Kunming, China
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Fadel JJ, Bahr GM, Echtay KS. Absence of effect of the antiretrovirals Duovir and Viraday on mitochondrial bioenergetics. J Cell Biochem 2018; 119:10384-10392. [PMID: 30187948 DOI: 10.1002/jcb.27384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 07/02/2018] [Indexed: 11/06/2022]
Abstract
Most toxicity associated with antiretroviral drugs is thought to result from disruption of mitochondrial function. Unfortunately, there are no validated laboratory markers for clinically assessing the onset of mitochondrial toxicity associated with antiretroviral therapy. In a previous study on mitochondrial hepatocytes, the protease inhibitor lopimune was shown to induce mitochondrial toxicity by increasing reactive oxygen species (ROS) production and decreasing respiratory control ratio (RCR) reflecting compromised mitochondrial efficiency in adenosine triphosphate production. Mitochondrial dysfunction and ROS production were directly correlated with the expression of uncoupling protein 2 (UCP2). In the current study we aim to determine the toxicity of nucleoside or nucleotide and nonnucleoside reverse-transcriptase inhibitors, Duovir and Viraday on liver mitochondria isolated from treated mice by monitoring UCP2 expression. Our results showed that both Duovir and Viraday had no effect on mitochondrial respiration states 2, 3, 4, and on RCR. In addition, ROS generation and UCP2 expression were not affected. In conclusion, our results indicate the difference in the mechanism of action of distinct classes of antiretroviral drugs on mitochondrial functions and may associate UCP2 expression with subclinical mitochondrial damage as marker of cellular oxidative stress.
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Affiliation(s)
- Jessy J Fadel
- Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Tripoli, Lebanon
| | - Georges M Bahr
- Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Tripoli, Lebanon
| | - Karim S Echtay
- Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Tripoli, Lebanon
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Ježek P, Holendová B, Garlid KD, Jabůrek M. Mitochondrial Uncoupling Proteins: Subtle Regulators of Cellular Redox Signaling. Antioxid Redox Signal 2018; 29:667-714. [PMID: 29351723 PMCID: PMC6071544 DOI: 10.1089/ars.2017.7225] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
SIGNIFICANCE Mitochondria are the energetic, metabolic, redox, and information signaling centers of the cell. Substrate pressure, mitochondrial network dynamics, and cristae morphology state are integrated by the protonmotive force Δp or its potential component, ΔΨ, which are attenuated by proton backflux into the matrix, termed uncoupling. The mitochondrial uncoupling proteins (UCP1-5) play an eminent role in the regulation of each of the mentioned aspects, being involved in numerous physiological events including redox signaling. Recent Advances: UCP2 structure, including purine nucleotide and fatty acid (FA) binding sites, strongly support the FA cycling mechanism: UCP2 expels FA anions, whereas uncoupling is achieved by the membrane backflux of protonated FA. Nascent FAs, cleaved by phospholipases, are preferential. The resulting Δp dissipation decreases superoxide formation dependent on Δp. UCP-mediated antioxidant protection and its impairment are expected to play a major role in cell physiology and pathology. Moreover, UCP2-mediated aspartate, oxaloacetate, and malate antiport with phosphate is expected to alter metabolism of cancer cells. CRITICAL ISSUES A wide range of UCP antioxidant effects and participations in redox signaling have been reported; however, mechanisms of UCP activation are still debated. Switching off/on the UCP2 protonophoretic function might serve as redox signaling either by employing/releasing the extra capacity of cell antioxidant systems or by directly increasing/decreasing mitochondrial superoxide sources. Rapid UCP2 degradation, FA levels, elevation of purine nucleotides, decreased Mg2+, or increased pyruvate accumulation may initiate UCP-mediated redox signaling. FUTURE DIRECTIONS Issues such as UCP2 participation in glucose sensing, neuronal (synaptic) function, and immune cell activation should be elucidated. Antioxid. Redox Signal. 29, 667-714.
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Affiliation(s)
- Petr Ježek
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
| | - Blanka Holendová
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
| | - Keith D Garlid
- 2 UCLA Cardiovascular Research Laboratory, David Geffen School of Medicine at UCLA , Los Angeles, California
| | - Martin Jabůrek
- 1 Department of Mitochondrial Physiology, Institute of Physiology of the Czech Academy of Sciences , Prague, Czech Republic
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Kawanishi M, Fukuda T, Shimomura M, Inoue Y, Wada T, Tasaka R, Yasui T, Sumi T. Expression of UCP2 is associated with sensitivity to platinum-based chemotherapy for ovarian serous carcinoma. Oncol Lett 2018; 15:9923-9928. [PMID: 29928365 DOI: 10.3892/ol.2018.8598] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 04/16/2018] [Indexed: 01/05/2023] Open
Abstract
The standard treatment for ovarian serous carcinoma is maximum debulking surgery and platinum-based chemotherapy. Despite the high response rate for chemotherapy, the majority of patients will be resistant to first-line agents and the prognosis for these patients is particularly poor. Currently there are no reliable methods to determine or predict platinum resistance. Uncoupling protein 2 (UCP2) is widely expressed in cancer cells and regulates the production of mitochondrial reactive oxygen species (ROS). A reduction in ROS is associated with carcinogenesis and chemoresistance. Downregulation of UCP2 significantly causes increased cell death following chemotherapy. The present study investigated the association between UCP2 expression and platinum sensitivity. The study included 54 patients with ovarian serous carcinoma (FIGO stages III and IV) who were treated at Osaka City University Hospital between January 2005 and December 2012. Patients were divided into a platinum-sensitive group (n=27) and platinum-resistant group (n=27) based on the platinum-free interval, which was calculated from the time of last platinum administration to the time of recurrence. UCP2 expression in human ovarian serous carcinoma cells was inhibited by genipin, and changes in carboplatin sensitivity were examined. The UCP2 weighted score was lower in the platinum-sensitive group than in the platinum resistant-group (P=0.005). In addition, patients in the low UCP2 expression group were more sensitive to platinum-based chemotherapy than those in the high UCP2 expression group (P=0.001). Sensitivity to carboplatin was significantly increased when UCP2 was inhibited in human ovarian serous carcinoma cells in vitro. UCP2 expression may be a predictive marker of the efficacy of platinum-based chemotherapy for patients with ovarian serous carcinoma.
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Affiliation(s)
- Masaru Kawanishi
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Takeshi Fukuda
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Masahiro Shimomura
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Yuta Inoue
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Takuma Wada
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Reiko Tasaka
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Tomoyo Yasui
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Toshiyuki Sumi
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
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Incalza MA, D'Oria R, Natalicchio A, Perrini S, Laviola L, Giorgino F. Oxidative stress and reactive oxygen species in endothelial dysfunction associated with cardiovascular and metabolic diseases. Vascul Pharmacol 2017; 100:1-19. [PMID: 28579545 DOI: 10.1016/j.vph.2017.05.005] [Citation(s) in RCA: 748] [Impact Index Per Article: 106.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Revised: 05/21/2017] [Accepted: 05/31/2017] [Indexed: 12/13/2022]
Abstract
Reactive oxygen species (ROS) are reactive intermediates of molecular oxygen that act as important second messengers within the cells; however, an imbalance between generation of reactive ROS and antioxidant defense systems represents the primary cause of endothelial dysfunction, leading to vascular damage in both metabolic and atherosclerotic diseases. Endothelial activation is the first alteration observed, and is characterized by an abnormal pro-inflammatory and pro-thrombotic phenotype of the endothelial cells lining the lumen of blood vessels. This ultimately leads to reduced nitric oxide (NO) bioavailability, impairment of the vascular tone and other endothelial phenotypic changes collectively termed endothelial dysfunction(s). This review will focus on the main mechanisms involved in the onset of endothelial dysfunction, with particular focus on inflammation and aberrant ROS production and on their relationship with classical and non-classical cardiovascular risk factors, such as hypertension, metabolic disorders, and aging. Furthermore, new mediators of vascular damage, such as microRNAs, will be discussed. Understanding mechanisms underlying the development of endothelial dysfunction is an important base of knowledge to prevent vascular damage in metabolic and cardiovascular diseases.
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Affiliation(s)
- Maria Angela Incalza
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Rossella D'Oria
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Annalisa Natalicchio
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Sebastio Perrini
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Luigi Laviola
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Giorgino
- Department of Emergency and Organ Transplantation, Section on Internal Medicine, Endocrinology, Andrology and Metabolic Diseases, University of Bari Aldo Moro, Bari, Italy.
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Imai K, Fukuda T, Wada T, Kawanishi M, Tasaka R, Yasui T, Sumi T. UCP2 expression may represent a predictive marker of neoadjuvant chemotherapy effectiveness for locally advanced uterine cervical cancer. Oncol Lett 2017; 14:951-957. [PMID: 28693257 DOI: 10.3892/ol.2017.6212] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 03/24/2017] [Indexed: 01/08/2023] Open
Abstract
Concurrent chemoradiotherapy is the standard treatment for locally advanced uterine cervical cancer. However, effective neoadjuvant chemotherapy (NAC) can reduce tumor size and facilitate hysterectomy for locally advanced uterine cervical cancer. NAC treatment could improve the prognosis of patients with locally advanced cervical cancer. However, if NAC is ineffective, radiotherapy must be pursued. This causes a delay in initiating the core treatment and results in a worse prognosis. Therefore, the identification of predictive markers of whether NAC is likely to be effective for the treatment of locally advanced uterine cervical cancer could improve patient prognosis. Uncoupling protein 2 (UCP2) is broadly expressed in cancer cells, and suppresses mitochondrial reactive oxygen species (ROS) production. UCP2 contributes to both carcinogenesis and chemoresistance by reducing ROS. Downregulation of UCP2 results in significantly increased cell death following chemotherapy. The present study investigated the association between UCP2 expression and NAC effectiveness. A total of 58 patients with locally advanced uterine cervical cancer (stage IIIA or IIIB) treated at Osaka City University Hospital between April 1995 and March 2010 were examined. Tumor tissue samples were obtained by punch biopsy prior to NAC. UCP2 expression was examined immunohistochemically and scored using a weighted scoring system. Patients were divided into NAC effective (n=34) and ineffective (n=24) groups. Furthermore, UCP2 expression in human uterine cervical cancer cells was inhibited by genipin, and changes in cisplatin sensitivity were examined. UCP2 weighted score was higher in the NAC ineffective group than in the NAC effective group (P=0.038). Additionally, the low UCP2 expression group was more sensitive to NAC than the high UCP2 expression group (P=0.041). Sensitivity to cisplatin was significantly increased when UCP2 was inhibited in human uterine cervical cancer cells in vitro. UCP2 expression may become a predictive marker of whether NAC is effective for patients with locally advanced uterine cervical cancer, which could improve patient prognosis.
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Affiliation(s)
- Kenji Imai
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Takeshi Fukuda
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Takuma Wada
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Masaru Kawanishi
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Reiko Tasaka
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Tomoyo Yasui
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
| | - Toshiyuki Sumi
- Department of Obstetrics and Gynecology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan
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16
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Schiffer TA, Friederich-Persson M. Mitochondrial Reactive Oxygen Species and Kidney Hypoxia in the Development of Diabetic Nephropathy. Front Physiol 2017; 8:211. [PMID: 28443030 PMCID: PMC5386984 DOI: 10.3389/fphys.2017.00211] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/23/2017] [Indexed: 12/21/2022] Open
Abstract
The underlying mechanisms in the development of diabetic nephropathy are currently unclear and likely consist of a series of dynamic events from the early to late stages of the disease. Diabetic nephropathy is currently without curative treatments and it is acknowledged that even the earliest clinical manifestation of nephropathy is preceded by an established morphological renal injury that is in turn preceded by functional and metabolic alterations. An early manifestation of the diabetic kidney is the development of kidney hypoxia that has been acknowledged as a common pathway to nephropathy. There have been reports of altered mitochondrial function in the diabetic kidney such as altered mitophagy, mitochondrial dynamics, uncoupling, and cellular signaling through hypoxia inducible factors and AMP-kinase. These factors are also likely to be intertwined in a complex manner. In this review, we discuss how these pathways are connected to mitochondrial production of reactive oxygen species (ROS) and how they may relate to the development of kidney hypoxia in diabetic nephropathy. From available literature, it is evident that early correction and/or prevention of mitochondrial dysfunction may be pivotal in the prevention and treatment of diabetic nephropathy.
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Affiliation(s)
- Tomas A Schiffer
- Department of Medical Cell Biology, Uppsala UniversityUppsala, Sweden.,Department of Medical and Health Sciences, Linköping UniversityLinköping, Sweden
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17
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Dhamrait SS, Maubaret C, Pedersen-Bjergaard U, Brull DJ, Gohlke P, Payne JR, World M, Thorsteinsson B, Humphries SE, Montgomery HE. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies. Bioessays 2016; 38 Suppl 1:S107-18. [DOI: 10.1002/bies.201670909] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/11/2015] [Indexed: 12/28/2022]
Affiliation(s)
- Sukhbir S. Dhamrait
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Department of Cardiology; Western Sussex Hospitals NHS Trust; West Sussex UK
| | - Cecilia Maubaret
- Centre INSERM U897-Epidemiologie-Biostatistique; Bordeaux France
| | - Ulrik Pedersen-Bjergaard
- Department of Cardiology, Nephrology and Endocrinology; Hillerød Hospital; Hillerød Denmark
- Faculty of Health Sciences; University of Copenhagen; Copenhagen Denmark
| | - David J. Brull
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Department of Cardiology; The Whittington Hospital NHS Trust; London UK
| | - Peter Gohlke
- Institute of Experimental and Clinical Pharmacology; University Hospital of Schleswig-Holstein; Kiel Germany
| | - John R. Payne
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
- Scottish National Advanced Heart Failure Service; Golden Jubilee National Hospital; Clydebank UK
| | - Michael World
- Royal Centre for Defence Medicine; Queen Elizabeth Hospital; Birmingham UK
| | - Birger Thorsteinsson
- Department of Cardiology, Nephrology and Endocrinology; Hillerød Hospital; Hillerød Denmark
- Faculty of Health Sciences; University of Copenhagen; Copenhagen Denmark
| | - Steve E. Humphries
- Centre for Cardiovascular Genetics, BHF Laboratories; University College London; London UK
| | - Hugh E. Montgomery
- UCL and National Centre for Sport, Exercise & Health; University College London; London UK
- UCL Institute for Human Health and Performance; University College London; London UK
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18
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Zhou Y, Zhang MJ, Li BH, Chen L, Pi Y, Yin YW, Long CY, Wang X, Sun MJ, Chen X, Gao CY, Li JC, Zhang LL. PPARγ Inhibits VSMC Proliferation and Migration via Attenuating Oxidative Stress through Upregulating UCP2. PLoS One 2016; 11:e0154720. [PMID: 27144886 PMCID: PMC4856345 DOI: 10.1371/journal.pone.0154720] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2016] [Accepted: 04/18/2016] [Indexed: 01/20/2023] Open
Abstract
Increasing evidence showed that abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are common event in the pathophysiology of many vascular diseases, including atherosclerosis and restenosis after angioplasty. Among the underlying mechanisms, oxidative stress is one of the principal contributors to the proliferation and migration of VSMCs. Oxidative stress occurs as a result of persistent production of reactive oxygen species (ROS). Recently, the protective effects of peroxisome proliferator-activated receptor γ (PPARγ) against oxidative stress/ROS in other cell types provide new insights to inhibit the suggests that PPARγ may regulate VSMCs function. However, it remains unclear whether activation of PPARγ can attenuate oxidative stress and further inhibit VSMC proliferation and migration. In this study, we therefore investigated the effect of PPARγ on inhibiting VSMC oxidative stress and the capability of proliferation and migration, and the potential role of mitochondrial uncoupling protein 2 (UCP2) in oxidative stress. It was found that platelet derived growth factor-BB (PDGF-BB) induced VSMC proliferation and migration as well as ROS production; PPARγ inhibited PDGF-BB-induced VSMC proliferation, migration and oxidative stress; PPARγ activation upregulated UCP2 expression in VSMCs; PPARγ inhibited PDGF-BB-induced ROS in VSMCs by upregulating UCP2 expression; PPARγ ameliorated injury-induced oxidative stress and intimal hyperplasia (IH) in UCP2-dependent manner. In conclusion, our study provides evidence that activation of PPARγ can attenuate ROS and VSMC proliferation and migration by upregulating UCP2 expression, and thus inhibit IH following carotid injury. These findings suggest PPARγ may represent a prospective target for the prevention and treatment of IH-associated vascular diseases.
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Affiliation(s)
- Yi Zhou
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Ming-Jie Zhang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Bing-Hu Li
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Lei Chen
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Yan Pi
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Yan-Wei Yin
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Chun-Yan Long
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Xu Wang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Meng-Jiao Sun
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Xue Chen
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Chang-Yue Gao
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
| | - Jing-Cheng Li
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
- * E-mail: (L-LZ); (J-CL)
| | - Li-Li Zhang
- Department of Neurology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing, 400042, PR China
- * E-mail: (L-LZ); (J-CL)
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19
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Romaschenko VP, Zinovkin RA, Galkin II, Zakharova VV, Panteleeva AA, Tokarchuk AV, Lyamzaev KG, Pletjushkina OY, Chernyak BV, Popova EN. Low Concentrations of Uncouplers of Oxidative Phosphorylation Prevent Inflammatory Activation of Endothelial Cells by Tumor Necrosis Factor. BIOCHEMISTRY (MOSCOW) 2016; 80:610-9. [PMID: 26071781 DOI: 10.1134/s0006297915050144] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In endothelial cells, mitochondria play an important regulatory role in physiology as well as in pathophysiology related to excessive inflammation. We have studied the effect of low doses of mitochondrial uncouplers on inflammatory activation of endothelial cells using the classic uncouplers 2,4-dinitrophenol and 4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazole, as well as the mitochondria-targeted cationic uncoupler dodecyltriphenylphosphonium (C12TPP). All of these uncouplers suppressed the expression of E-selectin, adhesion molecules ICAM1 and VCAM1, as well as the adhesion of neutrophils to endothelium induced by tumor necrosis factor (TNF). The antiinflammatory action of the uncouplers was at least partially mediated by the inhibition of NFκB activation due to a decrease in phosphorylation of the inhibitory subunit IκBα. The dynamic concentration range for the inhibition of ICAM1 expression by C12TPP was three orders of magnitude higher compared to the classic uncouplers. Probably, the decrease in membrane potential inhibited the accumulation of penetrating cations into mitochondria, thus lowering the uncoupling activity and preventing further loss of mitochondrial potential. Membrane potential recovery after the removal of the uncouplers did not abolish its antiinflammatory action. Thus, mild uncoupling could induce TNF resistance in endothelial cells. We found no significant stimulation of mitochondrial biogenesis or autophagy by the uncouplers. However, we observed a decrease in the relative amount of fragmented mitochondria. The latter may significantly change the signaling properties of mitochondria. Earlier we showed that both classic and mitochondria-targeted antioxidants inhibited the TNF-induced NFκB-dependent activation of endothelium. The present data suggest that the antiinflammatory effect of mild uncoupling is related to its antioxidant action.
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Affiliation(s)
- V P Romaschenko
- Lomonosov Moscow State University, Belozersky Institute of Physico-Chemical Biology, Moscow, 119991, Russia.
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20
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Abstract
AbstractEnergy restriction (ER; also known as caloric restriction) is the only nutritional intervention that has repeatedly been shown to increase lifespan in model organisms and may delay ageing in humans. In the present review we discuss current scientific literature on ER and its molecular, metabolic and hormonal effects. Moreover, criteria for the classification of substances that might induce positive ER-like changes without having to reduce energy intake are summarised. Additionally, the putative ER mimetics (ERM) 2-deoxy-d-glucose, metformin, rapamycin, resveratrol, spermidine and lipoic acid and their suggested molecular targets are discussed. While there are reports on these ERM candidates that describe lifespan extension in model organisms, data on longevity-inducing effects in higher organisms such as mice remain controversial or are missing. Furthermore, some of these candidates produce detrimental side effects such as immunosuppression or lactic acidosis, or have not been tested for safety in long-term studies. Up to now, there are no known ERM that could be recommended without limitations for use in humans.
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21
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Prakash C, Soni M, Kumar V. Biochemical and Molecular Alterations Following Arsenic-Induced Oxidative Stress and Mitochondrial Dysfunction in Rat Brain. Biol Trace Elem Res 2015; 167:121-9. [PMID: 25764338 DOI: 10.1007/s12011-015-0284-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 02/24/2015] [Indexed: 01/08/2023]
Abstract
Oxidative stress is associated with the generation of reactive oxygen species (ROS), which is supposed to be one of the mechanisms of arsenic-induced neurodegeneration. Mitochondria, being the major source of ROS generation may present an important target of arsenic-mediated neurotoxicity. Hence, we planned the study to elucidate the possible biochemical and molecular alterations induced by arsenic exposure in rat brain mitochondria. Chronic sodium arsenite treatment (25 ppm for 12 weeks) resulted in decreased activity of mitochondrial complexes I, II, and IV followed by increased ROS generation. There was decrease in mitochondrial superoxide dismutase (MnSOD) activity in arsenic-treated rat brain further showing increased superoxide radical generation in mitochondria. The decrease in MnSOD activity might be responsible for the increased protein and lipid oxidation as observed in our study. Protein and messenger RNA (mRNA) levels of MnSOD and mitochondrial uncoupling protein 2 (UCP-2) were downregulated suggesting decreased removal of ROS in rat brain. Fourier transform infrared (FTIR) spectroscopy analysis revealed significant decrease in amide A, amide I, amide II, and Olefinic = CH stretching band area suggesting molecular alteration in proteins and lipids after arsenic treatment. The results of present study indicate that arsenic-induced disturbed mitochondrial metabolism, decreased removal of ROS, decrease in protein synthesis, and altered membrane lipid polarity and fluidity may be responsible for the mitochondrial oxidative damage in rat brain that may further be implicated as contributing factor in arsenic-induced neurodegeneration.
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Affiliation(s)
- Chandra Prakash
- Department of Biochemistry, Maharshi Dayanand University, Rohtak, 124001, Haryana, India
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22
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Jun Z, Ibrahim MM, Dezheng G, Bo Y, Qiong W, Yuan Z. UCP2 protects against amyloid beta toxicity and oxidative stress in primary neuronal culture. Biomed Pharmacother 2015; 74:211-4. [PMID: 26349987 DOI: 10.1016/j.biopha.2015.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 08/02/2015] [Indexed: 12/13/2022] Open
Abstract
AD is a common neurodegenerative disease characterized by aggregated amyloid-beta (Aβ) peptide, and oxidative stress, while uncoupling protein 2 (UCP2) is a member of the anion carrier family, predicted the existence of a protein-regulated proton leak with the main purpose of controlling mitochondrial oxidative stress, reduce the generation of superoxide anion. we use the primary hippocampal neurons and add the different doses of Aβ1-40, then observe the change of UCP2 at different concentrations of Aβ, activity of LDH and the content of NO. Our results provide novel insight that UCP2 may protect hippocampal neurons exposed to amyloid β protein through decreasing ROS production. 20μmol/L Aβ1-40 significantly increased the activity of LDH and the content of NO. According to the correlation analysis, NO was significantly correlation with LDH, and UCP2 was significantly correlation with NO. These results suggest the potential of UCP2 as a therapeutic candidate for treating neurodegenerative diseases such as AD.
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Affiliation(s)
- Zhang Jun
- Department of Pathology, Dalian Medical University, Dalian, China
| | - M M Ibrahim
- Department of Pathology, Dalian Medical University, Dalian, China
| | - Gong Dezheng
- Department of Physiology, Dalian Medical University, Dalian, China
| | - Yuan Bo
- Department of Physiology, Dalian Medical University, Dalian, China
| | - Wu Qiong
- Department of Physiology, Dalian Medical University, Dalian, China
| | - Zou Yuan
- Department of Physiology, Dalian Medical University, Dalian, China.
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23
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Dhamrait SS, Maubaret C, Pedersen-Bjergaard U, Brull DJ, Gohlke P, Payne JR, World M, Thorsteinsson B, Humphries SE, Montgomery HE. Mitochondrial uncoupling proteins regulate angiotensin-converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies. ACTA ACUST UNITED AC 2015; 1:70-81. [PMID: 27347560 PMCID: PMC4915277 DOI: 10.1002/icl3.1019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/11/2015] [Indexed: 12/18/2022]
Abstract
Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin‐converting enzyme (ACE) is the central component of endocrine and local tissue renin–angiotensin systems (RAS), which also regulate diverse aspects of whole‐body metabolism and mitochondrial function (partly through altering mitochondrial UCP expression). We show that ACE expression also appears to be regulated by mitochondrial UCPs. In genetic analysis of two unrelated populations (healthy young UK men and Scandinavian diabetic patients) serum ACE (sACE) activity was significantly higher amongst UCP3‐55C (rather than T) and UCP2 I (rather than D) allele carriers. RNA interference against UCP2 in human umbilical vein endothelial cells reduced UCP2 mRNA sixfold (P < 0·01) whilst increasing ACE expression within a physiological range (<1·8‐fold at 48 h; P < 0·01). Our findings suggest novel hypotheses. Firstly, cellular feedback regulation may occur between UCPs and ACE. Secondly, cellular UCP regulation of sACE suggests a novel means of crosstalk between (and mutual regulation of) cellular and endocrine metabolism. This might partly explain the reduced risk of developing diabetes and metabolic syndrome with RAS antagonists and offer insight into the origins of cardiovascular disease in which UCPs and ACE both play a role.
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Affiliation(s)
- Sukhbir S Dhamrait
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Department of Cardiology Western Sussex Hospitals NHS Trust West Sussex UK
| | | | - Ulrik Pedersen-Bjergaard
- Department of Cardiology, Nephrology and Endocrinology Hillerød Hospital Hillerød Denmark; Faculty of Health Sciences University of Copenhagen Copenhagen Denmark
| | - David J Brull
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Department of Cardiology The Whittington Hospital NHS Trust London UK
| | - Peter Gohlke
- Institute of Experimental and Clinical Pharmacology University Hospital of Schleswig-Holstein Kiel Germany
| | - John R Payne
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK; Scottish National Advanced Heart Failure Service Golden Jubilee National Hospital Clydebank UK
| | - Michael World
- Royal Centre for Defence Medicine Queen Elizabeth Hospital Birmingham UK
| | - Birger Thorsteinsson
- Department of Cardiology, Nephrology and Endocrinology Hillerød Hospital Hillerød Denmark; Faculty of Health Sciences University of Copenhagen Copenhagen Denmark
| | - Steve E Humphries
- Centre for Cardiovascular Genetics, BHF Laboratories University College London London UK
| | - Hugh E Montgomery
- UCL and National Centre for Sport, Exercise & Health University College London London UK; UCL Institute for Human Health and Performance University College London London UK
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24
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Szewczyk A, Jarmuszkiewicz W, Koziel A, Sobieraj I, Nobik W, Lukasiak A, Skup A, Bednarczyk P, Drabarek B, Dymkowska D, Wrzosek A, Zablocki K. Mitochondrial mechanisms of endothelial dysfunction. Pharmacol Rep 2015; 67:704-10. [PMID: 26321271 DOI: 10.1016/j.pharep.2015.04.009] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/10/2015] [Accepted: 04/14/2015] [Indexed: 01/09/2023]
Abstract
Endothelial cells play an important physiological role in vascular homeostasis. They are also the first barrier that separates blood from deeper layers of blood vessels and extravascular tissues. Thus, they are exposed to various physiological blood components as well as challenged by pathological stimuli, which may exert harmful effects on the vascular system by stimulation of excessive generation of reactive oxygen species (ROS). The major sources of ROS are NADPH oxidase and mitochondrial respiratory chain complexes. Modulation of mitochondrial energy metabolism in endothelial cells is thought to be a promising target for therapy in various cardiovascular diseases. Uncoupling protein 2 (UCP2) is a regulator of mitochondrial ROS generation and can antagonise oxidative stress-induced endothelial dysfunction. Several studies have revealed the important role of UCP2 in hyperglycaemia-induced modifications of mitochondrial function in endothelial cells. Additionally, potassium fluxes through the inner mitochondrial membrane, which are involved in ROS synthesis, affect the mitochondrial volume and change both the mitochondrial membrane potential and the transport of calcium into the mitochondria. In this review, we concentrate on the mitochondrial role in the cytoprotection phenomena of endothelial cells.
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Affiliation(s)
- Adam Szewczyk
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Warszawa, Poland
| | | | - Agnieszka Koziel
- Department of Bioenergetics, Adam Mickiewicz University, Poznań, Poland
| | - Izabela Sobieraj
- Department of Bioenergetics, Adam Mickiewicz University, Poznań, Poland
| | - Wioletta Nobik
- Department of Bioenergetics, Adam Mickiewicz University, Poznań, Poland
| | - Agnieszka Lukasiak
- Department of Biophysics, Warsaw University of Life Sciences-SGGW, Warszawa, Poland
| | - Agata Skup
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Warszawa, Poland
| | - Piotr Bednarczyk
- Department of Biophysics, Warsaw University of Life Sciences-SGGW, Warszawa, Poland
| | - Beata Drabarek
- Laboratory of Cellular Metabolism, Nencki Institute of Experimental Biology, Warszawa, Poland
| | - Dorota Dymkowska
- Laboratory of Cellular Metabolism, Nencki Institute of Experimental Biology, Warszawa, Poland
| | - Antoni Wrzosek
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, Warszawa, Poland.
| | - Krzysztof Zablocki
- Laboratory of Cellular Metabolism, Nencki Institute of Experimental Biology, Warszawa, Poland
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25
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Lopimune-induced mitochondrial toxicity is attenuated by increased uncoupling protein-2 level in treated mouse hepatocytes. Biochem J 2015; 468:401-7. [PMID: 26173235 DOI: 10.1042/bj20150195] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 04/13/2015] [Indexed: 02/01/2023]
Abstract
Although the protease inhibitor (PI) Lopimune has proven to be effective, no studies have examined the side effects of Lopimune on mitochondrial bioenergetics in hepatocytes. The objective of the present study is to evaluate mitochondrial respiration, production of reactive oxygen species (ROS) and expression of uncoupling protein-2 (UCP2) in mouse hepatocytes following Lopimune administration. Mitochondria were extracted from mouse liver using differential centrifugation and hepatocytes were isolated by the collagenase perfusion procedure. Mitochondrial respiration was measured using a Rank Brothers oxygen electrode. ROS production in hepatocytes was monitored by flow cytometry using a 2',7'-dichlorofluorescin diacetate probe and UCP2 protein expression was detected by Western blotting. We found that Lopimune induced a significant decrease of approximately 30% in the respiratory control ratio (RCR) starting from day 4 until day 9 of treatment. This decrease was due to an increase in state 4 respiration, reflecting an increase in mitochondrial proton leak. State 2 and state 3 respirations were not affected. Moreover, ROS production significantly increased by about 2-fold after day 1 of treatment and decreased after day 3, returning to the resting level on day 5. Interestingly, UCP2 which is absent from control hepatocytes, was expressed starting from day 4 of treatment. Our findings indicate that Lopimune-induced proton leak, mediated by UCP2, may represent a response to inhibit the production of ROS as a negative feedback regulatory mechanism. These results imply a potential involvement of UCP2 in the regulation of oxidative stress and add new insights into the understanding of mitochondrial toxicity induced by PIs.
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26
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Haslip M, Dostanic I, Huang Y, Zhang Y, Russell KS, Jurczak MJ, Mannam P, Giordano F, Erzurum SC, Lee PJ. Endothelial uncoupling protein 2 regulates mitophagy and pulmonary hypertension during intermittent hypoxia. Arterioscler Thromb Vasc Biol 2015; 35:1166-78. [PMID: 25814675 DOI: 10.1161/atvbaha.114.304865] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 03/10/2015] [Indexed: 01/06/2023]
Abstract
OBJECTIVES Pulmonary hypertension (PH) is a process of lung vascular remodeling, which can lead to right heart dysfunction and significant morbidity. The underlying mechanisms leading to PH are not well understood, and therapies are limited. Using intermittent hypoxia (IH) as a model of oxidant-induced PH, we identified an important role for endothelial cell mitophagy via mitochondrial uncoupling protein 2 (Ucp2) in the development of IH-induced PH. APPROACH AND RESULTS Ucp2 endothelial knockout (VE-KO) and Ucp2 Flox (Flox) mice were subjected to 5 weeks of IH. Ucp2 VE-KO mice exhibited higher right ventricular systolic pressure and worse right heart hypertrophy, as measured by increased right ventricle weight/left ventricle plus septal weight (RV/LV+S) ratio, at baseline and after IH. These changes were accompanied by increased mitophagy. Primary mouse lung endothelial cells transfected with Ucp2 siRNA and subjected to cyclic exposures to CoCl2 (chemical hypoxia) showed increased mitophagy, as measured by PTEN-induced putative kinase 1 and LC3BII/I ratios, decreased mitochondrial biogenesis, and increased apoptosis. Similar results were obtained in primary lung endothelial cells isolated from VE-KO mice. Moreover, silencing PTEN-induced putative kinase 1 in the endothelium of Ucp2 knockout mice, using endothelial-targeted lentiviral silencing RNA in vivo, prevented IH-induced PH. Human pulmonary artery endothelial cells from people with PH demonstrated changes similar to Ucp2-silenced mouse lung endothelial cells. CONCLUSIONS The loss of endothelial Ucp2 leads to excessive PTEN-induced putative kinase 1-induced mitophagy, inadequate mitochondrial biosynthesis, and increased apoptosis in endothelium. An endothelial Ucp2-PTEN-induced putative kinase 1 axis may be effective therapeutic targets in PH.
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Affiliation(s)
- Maria Haslip
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Iva Dostanic
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Yan Huang
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Yi Zhang
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Kerry S Russell
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Michael J Jurczak
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Praveen Mannam
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Frank Giordano
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Serpil C Erzurum
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.)
| | - Patty J Lee
- From the Department of Medicine, Section of Pulmonary, Critical Care and Sleep Medicine (M.H., I.D., Y.Z., P.M., P.J.L.), Section of Cardiovascular Disease (Y.H., K.S.R, F.G.), and Section of Endocrinology and Metabolism (M.J.J.), Yale University School of Medicine, New Haven, CT; and Department of Pathobiology, Lerner Research Institute and Respiratory Institute, Cleveland Clinic, OH (S.C.E.).
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Shen Y, Wen Z, Wang N, Zheng Z, Liu K, Xia X, Gu Q, Shi Y, Xu X. Investigation of variants in UCP2 in Chinese type 2 diabetes and diabetic retinopathy. PLoS One 2014; 9:e112670. [PMID: 25396419 PMCID: PMC4232517 DOI: 10.1371/journal.pone.0112670] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 10/10/2014] [Indexed: 12/11/2022] Open
Abstract
Purpose The aim of this study was to investigate variants in UCP2 genes in type 2 diabetes mellitus (DM) and diabetic retinopathy (DR) in Chinese population. Materials and Methods We conducted a single nucleotide polymorphism-based and haplotype-based case-control study between the variants of UCP2 and DM and between the variants of UCP2 and DR in 479 Chinese patients with type 2 DM and 479 control subjects without DM. Two SNPs (rs660339 and rs659366) were selected as genetic markers. Results The risk allele C at UCP2 rs660339 was closely associated with DM in Chinese population. There was significant difference in rs660339 between DM and controls (P = 0.0016; OR [95%CI] = 1.37 (1.14–1.65)). Subjects who were homozygous of the C allele were more likely to develop DM. The frequency of C allele was higher in DM (58%) than in control (51%). But this locus didn't have a definite effect on the onset of non-proliferative diabetic retinopathy (NPDR) (P = 0.44; OR [95%CI] = 0.80 (0.56–1.14)) and proliferative diabetic retinopathy (PDR) (P = 1.00; OR [95%CI] = 0.99 (0.74–1.34)) comparing to subjects with DM without retinopathy (DWR), respectively. Moreover, the UCP2 rs659366 polymorphism showed no significant difference between DM and control (P = 0.66; OR [95%CI] = 1.10 (0.91–1.32)). However, there was a significant difference between PDR and DWR (P = 0.016; OR [95%CI] = 0.66 (0.49–0.90)), but there was no difference between NPDR and DWR (P = 1.00; OR [95%CI] = 0.96 (0.67–1.37)). Participants who carried the G allele at rs659366 were more likely to develop PDR. For the haplotype, C-A was present more frequently in DM than in control (16% vs 7%), indicating that it was risky, and T-A was present less in DM than in control (29% vs 35%). Haplotype frequencies in DR and DWR showed no significant difference (P = 0.068). Conclusion It was indicated that UCP2 may be implicated in the pathogenesis of type 2 DM and DR in Chinese population.
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Affiliation(s)
- Yinchen Shen
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| | - Zujia Wen
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Ning Wang
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
- * E-mail:
| | - Zhi Zheng
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| | - Kun Liu
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| | - Xin Xia
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| | - Qing Gu
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
| | - Yongyong Shi
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education), Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Xun Xu
- Department of Ophthalmology, Shanghai First People's Hospital, Shanghai Jiao Tong University, Shanghai, People's Republic of China, Shanghai Key Laboratory of Fundus Disease, Shanghai, People's Republic of China
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Tang X, Luo YX, Chen HZ, Liu DP. Mitochondria, endothelial cell function, and vascular diseases. Front Physiol 2014; 5:175. [PMID: 24834056 PMCID: PMC4018556 DOI: 10.3389/fphys.2014.00175] [Citation(s) in RCA: 254] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/16/2014] [Indexed: 12/20/2022] Open
Abstract
Mitochondria are perhaps the most sophisticated and dynamic responsive sensing systems in eukaryotic cells. The role of mitochondria goes beyond their capacity to create molecular fuel and includes the generation of reactive oxygen species, the regulation of calcium, and the activation of cell death. In endothelial cells, mitochondria have a profound impact on cellular function under both healthy and diseased conditions. In this review, we summarize the basic functions of mitochondria in endothelial cells and discuss the roles of mitochondria in endothelial dysfunction and vascular diseases, including atherosclerosis, diabetic vascular dysfunction, pulmonary artery hypertension, and hypertension. Finally, the potential therapeutic strategies to improve mitochondrial function in endothelial cells and vascular diseases are also discussed, with a focus on mitochondrial-targeted antioxidants and calorie restriction.
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Affiliation(s)
- Xiaoqiang Tang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, China
| | - Yu-Xuan Luo
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, China
| | - Hou-Zao Chen
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, China
| | - De-Pei Liu
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, China
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29
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Streck EL, Gonçalves CL, Furlanetto CB, Scaini G, Dal-Pizzol F, Quevedo J. Mitochondria and the central nervous system: searching for a pathophysiological basis of psychiatric disorders. REVISTA BRASILEIRA DE PSIQUIATRIA 2014; 36:156-67. [DOI: 10.1590/1516-4446-2013-1224] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/03/2013] [Indexed: 12/20/2022]
Affiliation(s)
- Emilio L. Streck
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Cinara L. Gonçalves
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Camila B. Furlanetto
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Giselli Scaini
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - Felipe Dal-Pizzol
- Universidade do Extremo Sul Catarinense (UNESC), Brazil; National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil
| | - João Quevedo
- National Science and Technology Institute for Translational Medicine (INCT-TM), Brazil; Center of Excellence in Applied Neurosciences of Santa Catarina (NENASC), Brazil; UNESC, Brazil
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Age-dependent effects of UCP2 deficiency on experimental acute pancreatitis in mice. PLoS One 2014; 9:e94494. [PMID: 24721982 PMCID: PMC3983280 DOI: 10.1371/journal.pone.0094494] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/17/2014] [Indexed: 01/08/2023] Open
Abstract
Reactive oxygen species (ROS) have been implicated in the pathogenesis of acute pancreatitis (AP) for many years but experimental evidence is still limited. Uncoupling protein 2 (UCP2)-deficient mice are an accepted model of age-related oxidative stress. Here, we have analysed how UCP2 deficiency affects the severity of experimental AP in young and older mice (3 and 12 months old, respectively) triggered by up to 7 injections of the secretagogue cerulein (50 μg/kg body weight) at hourly intervals. Disease severity was assessed at time points from 3 hours to 7 days based on pancreatic histopathology, serum levels of alpha-amylase, intrapancreatic trypsin activation and levels of myeloperoxidase (MPO) in lung and pancreatic tissue. Furthermore, in vitro studies with pancreatic acini were performed. At an age of 3 months, UCP2-/- mice and wild-type (WT) C57BL/6 mice were virtually indistinguishable with respect to disease severity. In contrast, 12 months old UCP2-/- mice developed a more severe pancreatic damage than WT mice at late time points after the induction of AP (24 h and 7 days, respectively), suggesting retarded regeneration. Furthermore, a higher peak level of alpha-amylase activity and gradually increased MPO levels in pancreatic and lung tissue were observed in UCP2-/- mice. Interestingly, intrapancreatic trypsin activities (in vivo studies) and intraacinar trypsin and elastase activation in response to cerulein treatment (in vitro studies) were not enhanced but even diminished in the knockout strain. Finally, UCP2-/- mice displayed a diminished ratio of reduced and oxidized glutathione in serum but no increased ROS levels in pancreatic acini. Together, our data indicate an aggravating effect of UCP2 deficiency on the severity of experimental AP in older but not in young mice. We suggest that increased severity of AP in 12 months old UCP2-/- is caused by an imbalanced inflammatory response but is unrelated to acinar cell functions.
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Chronic aerobic exercise training attenuates aortic stiffening and endothelial dysfunction through preserving aortic mitochondrial function in aged rats. Exp Gerontol 2014; 56:37-44. [PMID: 24607516 DOI: 10.1016/j.exger.2014.02.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/22/2014] [Accepted: 02/24/2014] [Indexed: 01/22/2023]
Abstract
Aging leads to large vessel arterial stiffening and endothelial dysfunction, which are important determinants of cardiovascular risk. The aim of present work was to assess the effects of chronic aerobic exercise training on aortic stiffening and endothelial dysfunction in aged rats and investigate the underlying mechanism about mitochondrial function. Chronic aerobic exercise training attenuated aortic stiffening with age marked by reduced collagen concentration, increased elastin concentration and reduced pulse wave velocity (PWV), and prevented aging-related endothelial dysfunction marked by improved endothelium-mediated vascular relaxation of aortas in response to acetylcholine. Chronic aerobic exercise training abated oxidative stress and nitrosative stress in aortas of aged rats. More importantly, we found that chronic aerobic exercise training in old rats preserved aortic mitochondrial function marked by reduced reactive oxygen species (ROS) formation and mitochondrial swelling, increased ATP formation and mitochondrial DNA content, and restored activities of complexes I and III and electron-coupling capacity between complexes I and III and between complexes II and III. In addition, it was found that chronic aerobic exercise training in old rats enhanced protein expression of uncoupling protein 2 (UCP-2), peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), manganese superoxide dismutase (Mn-SOD), aldehyde dehydrogenase 2 (ALDH-2), prohibitin (PHB) and AMP-activated kinase (AMPK) phosphorylation in aortas. In conclusion, chronic aerobic exercise training preserved mitochondrial function in aortas, which, at least in part, explained the aorta-protecting effects of exercise training in aging.
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JEŽEK P, OLEJÁR T, SMOLKOVÁ K, JEŽEK J, DLASKOVÁ A, PLECITÁ-HLAVATÁ L, ZELENKA J, ŠPAČEK T, ENGSTOVÁ H, PAJUELO REGUERA D, JABŮREK M. Antioxidant and Regulatory Role of Mitochondrial Uncoupling Protein UCP2 in Pancreatic β-cells. Physiol Res 2014; 63:S73-91. [DOI: 10.33549/physiolres.932633] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Research on brown adipose tissue and its hallmark protein, mitochondrial uncoupling protein UCP1, has been conducted for half a century and has been traditionally studied in the Institute of Physiology (AS CR, Prague), likewise UCP2 residing in multiple tissues for the last two decades. Our group has significantly contributed to the elucidation of UCP uncoupling mechanism, fully dependent on free fatty acids (FFAs) within the inner mitochondrial membrane. Now we review UCP2 physiological roles emphasizing its roles in pancreatic β-cells, such as antioxidant role, possible tuning of redox homeostasis (consequently UCP2 participation in redox regulations), and fine regulation of glucose-stimulated insulin secretion (GSIS). For example, NADPH has been firmly established as being a modulator of GSIS and since UCP2 may influence redox homeostasis, it likely affects NADPH levels. We also point out the role of phospholipase iPLA2 isoform in providing FFAs for the UCP2 antioxidant function. Such initiation of mild uncoupling hypothetically precedes lipotoxicity in pancreatic β-cells until it reaches the pathological threshold, after which the antioxidant role of UCP2 can be no more cell-protective, for example due to oxidative stress-accumulated mutations in mtDNA. These mechanisms, together with impaired autocrine insulin function belong to important causes of Type 2 diabetes etiology.
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Affiliation(s)
- P. JEŽEK
- Department of Membrane Transport Biophysics, Institute of Physiology Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Echtay KS, Brand MD. 4-Hydroxy-2-nonenal and uncoupling proteins: an approach for regulation of mitochondrial ROS production. Redox Rep 2013; 12:26-9. [PMID: 17263904 DOI: 10.1179/135100007x162158] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
One factor that has the potential to regulate reactive oxygen species (ROS) generation is the mild uncoupling of oxidative phosphorylation, i.e. proton (H(+)) leak across the mitochondrial inner membrane. Proton leak has been shown to attenuate ROS generation, whereas ROS and their derivatives (such as superoxide and hydroxynonenal) have been shown to induce H(+) leak through uncoupling proteins (UCPs). This suggests the existence of a feedback loop between ROS and H(+) leak mediated through UCPs. Although the physiological functions of the new UCPs, such as UCP2 and UCP3, are still not established, extensive data support the idea that these mitochondrial carrier proteins are involved in the control of ROS generation. The molecular basis of both ROS generation and hydroxynonenal-induced uncoupling through UCPs is reviewed and the consequences of their interaction for protection against excessive ROS production at the expense of energy production is discussed.
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Affiliation(s)
- Karim S Echtay
- Department of Biomedical Sciences, Faculty of Medicine and Medical Sciences, University of Balamand, Tripoli, Lebanon.
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34
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Graw JA, von Haefen C, Poyraz D, Möbius N, Sifringer M, Spies CD. Chronic alcohol consumption increases the expression of uncoupling protein-2 and -4 in the brain. Alcohol Clin Exp Res 2013; 37:1650-6. [PMID: 23800309 DOI: 10.1111/acer.12144] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/07/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND Chronic alcohol consumption leads to oxidative stress in a variety of cells, especially in brain cells because they have a reduced oxidative metabolism of alcohol. Uncoupling proteins (UCPs) are anion channels of the inner mitochondrial membrane, which can decouple internal respiration. "Mild uncoupling" of the mitochondrial respiratory chain leads to a reduced production of free radicals (reactive oxygen species) and a reduction in oxidative cell stress. The extent to which chronic alcohol consumption regulates UCP-2 and -4 in the brain is still unknown. METHODS We examined the effects of a 12-week 5% alcohol diet in the brain of male Wistar rats (n = 34). Cerebral gene and protein expression of UCP-2, -4, as well as Bcl-2, and the release of cytochrome c out of the mitochondria were detected by real-time polymerase chain reaction and Western blot analysis. The percentage of degenerated cells was determined by Fluoro-Jade B staining of brain slices. RESULTS Brains of rats with a chronic alcohol diet showed an increased gene and protein expression of UCP-2 and -4. The expression of the antiapoptotic protein Bcl-2 in the brain of the alcohol-treated animals was decreased significantly, whereas cytochrome c release from mitochondria was increased. In addition increased neurodegeneration could be demonstrated in the alcohol-treated animals. CONCLUSIONS Chronic alcohol consumption leads to a cerebral induction of UCP-2 and -4 with a simultaneous decrease in the antiapoptotic protein Bcl-2, cytochrome c release from mitochondria and increased neurodegeneration. This study reveals a compensatory effect of UCP-2 and -4 in the brain during chronic alcohol consumption.
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Affiliation(s)
- Jan A Graw
- Department of Anesthesiology and Intensive Care Medicine, Campus Charité Mitte and Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Berlin, Germany
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Abstract
In contrast to their role in cell types with higher energy demands, mitochondria in endothelial cells primarily function in signaling cellular responses to environmental cues. This article provides an overview of key aspects of mitochondrial biology in endothelial cells, including subcellular location, biogenesis, dynamics, autophagy, reactive oxygen species production and signaling, calcium homeostasis, regulated cell death, and heme biosynthesis. In each section, we introduce key concepts and then review studies showing the importance of that mechanism to endothelial control of vasomotor tone, angiogenesis, and/or inflammatory activation. We particularly highlight the small number of clinical and translational studies that have investigated each mechanism in human subjects. Finally, we review interventions that target different aspects of mitochondrial function and their effects on endothelial function. The ultimate goal of such research is the identification of new approaches for therapy. The reviewed studies make it clear that mitochondria are important in endothelial physiology and pathophysiology. A great deal of work will be needed, however, before mitochondria-directed therapies are available for the prevention and treatment of cardiovascular disease.
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Affiliation(s)
- Matthew A Kluge
- Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA 02118, USA
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36
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Suski JM, Schönfeld P, Bonora M, Shabalina I, Pinton P, Więckowski MR. Guanosine diphosphate exerts a lower effect on superoxide release from mitochondrial matrix in the brains of uncoupling protein-2 knockout mice: new evidence for a putative novel function of uncoupling proteins as superoxide anion transporters. Biochem Biophys Res Commun 2012; 428:234-8. [PMID: 23068098 DOI: 10.1016/j.bbrc.2012.10.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 10/05/2012] [Indexed: 12/18/2022]
Abstract
In this report, we show new experimental evidence that, in mouse brain mitochondria, uncoupling protein-2 (UCP2) can be involved in superoxide (O(2)(·-)) removal from the mitochondrial matrix. We found that the effect of guanosine 5'-diphosphate (GDP) on the rate of reactive oxygen species (ROS) release from brain mitochondria of UCP2 knockout mice was less pronounced compared to the wild type animals. This putative novel UCP2 activity, evaluated by the use of UCP2-knockout transgenic animals, along with the known antioxidant defence systems, may provide additional protection from ROS in brain mitochondria.
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Affiliation(s)
- Jan M Suski
- Department of Biochemistry, Nencki Institute of Experimental Biology, Warsaw, Poland
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Clarke KJ, Porter RK. Uncoupling protein 1 dependent reactive oxygen species production by thymus mitochondria. Int J Biochem Cell Biol 2012; 45:81-9. [PMID: 23036787 DOI: 10.1016/j.biocel.2012.09.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 09/03/2012] [Accepted: 09/25/2012] [Indexed: 11/29/2022]
Abstract
We have previously shown that uncoupling protein 1 is present in thymus and has a role in T-cell development. As reactive oxygen species have been implicated in T-cell development, we set out to determine whether uncoupling protein 1 had the potential to regulate reactive oxygen species production in mitochondria isolated from thymus. This was achieved by inhibiting proton leak through uncoupling protein 1 using the purine nucleotide GDP and through ablation of uncoupling protein 1, measuring the amplex red sensitive reactive oxygen species production by mitochondria. In this work we demonstrate, for the first time, that uncoupling protein 1 has the potential to regulate reactive oxygen species production in thymus mitochondria. We also show that reverse electron transport is possible in thymus mitochondria respiring on succinate and glycerol-3-phosphate. The implications of this regulatory role for uncoupling protein 1 are discussed in the context of thymus function. This article is part of a Directed Issue entitled: Bioenergetic dysfunction, adaptation and therapy.
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Affiliation(s)
- Kieran J Clarke
- School of Biochemistry and Immunology, Trinity Institute of Biomedical Science, Trinity College Dublin, Ireland.
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Friederich-Persson M, Aslam S, Nordquist L, Welch WJ, Wilcox CS, Palm F. Acute knockdown of uncoupling protein-2 increases uncoupling via the adenine nucleotide transporter and decreases oxidative stress in diabetic kidneys. PLoS One 2012; 7:e39635. [PMID: 22768304 PMCID: PMC3388100 DOI: 10.1371/journal.pone.0039635] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 05/25/2012] [Indexed: 11/18/2022] Open
Abstract
Increased O2 metabolism resulting in chronic hypoxia is common in models of endstage renal disease. Mitochondrial uncoupling increases O2 consumption but the ensuing reduction in mitochondrial membrane potential may limit excessive oxidative stress. The present study addressed the hypothesis that mitochondrial uncoupling regulates mitochondria function and oxidative stress in the diabetic kidney. Isolated mitochondria from kidney cortex of control and streptozotocin-induced diabetic rats were studied before and after siRNA knockdown of uncoupling protein-2 (UCP-2). Diabetes resulted in increased UCP-2 protein expression and UCP-2-mediated uncoupling, but normal mitochondria membrane potential. This uncoupling was inhibited by GDP, which also increased the membrane potential. siRNA reduced UCP-2 protein expression in controls and diabetics (−30–50%), but paradoxically further increased uncoupling and markedly reduced the membrane potential. This siRNA mediated uncoupling was unaffected by GDP but was blocked by ADP and carboxyatractylate (CAT). Mitochondria membrane potential after UCP-2 siRNA was unaffected by GDP but increased by CAT. This demonstrated that further increased mitochondria uncoupling after siRNA towards UCP-2 is mediated through the adenine nucleotide transporter (ANT). The increased oxidative stress in the diabetic kidney, manifested as increased thiobarbituric acids, was reduced by knocking down UCP-2 whereas whole-body oxidative stress, manifested as increased circulating malondialdehyde, remained unaffected. All parameters investigated were unaffected by scrambled siRNA. In conclusion, mitochondrial uncoupling via UCP-2 regulates mitochondria membrane potential in diabetes. However, blockade of the diabetes-induced upregulation of UCP- 2 results in excessive uncoupling and reduced oxidative stress in the kidney via activation of ANT.
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Affiliation(s)
- Malou Friederich-Persson
- Division of Integrative Physiology, Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden.
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Tian XY, Wong WT, Xu A, Lu Y, Zhang Y, Wang L, Cheang WS, Wang Y, Yao X, Huang Y. Uncoupling protein-2 protects endothelial function in diet-induced obese mice. Circ Res 2012; 110:1211-6. [PMID: 22461387 DOI: 10.1161/circresaha.111.262170] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
RATIONALE Previous studies indicate uncoupling protein-2 (UCP2) as an antioxidant defense against endothelial dysfunction in hypertension. UCP2 also regulates insulin secretion and action. However, the role of UCP2 in endothelial dysfunction associated with diabetes and obesity is unclear. OBJECTIVE UCP2 protects against endothelial dysfunction induced by high-fat diet through inhibition of reactive oxygen species (ROS) production, and subsequent increase of nitric oxide bioavailability. METHODS AND RESULTS Endothelium-dependent relaxation (EDR) in aortae and mesenteric arteries in response to acetylcholine was measured in wire myograph. Flow-mediated vasodilatation in 2(nd)-order mesenteric arteries was measured in pressure myograph. ROS production is measured by CM-H(2)DCFDA and DHE fluorescence. High-glucose exposure reduced EDR in mouse aortae, which was exaggerated in UCP2 knockout (KO) mice, whereas UCP2 overexpression by adenoviral infection (AdUCP2) restored the impaired EDR. Impairment of EDR and flow-mediated vasodilatation in aortae and mesenteric arteries from high-fat diet-induced obese mice (DIO) was exaggerated in UCP2KO DIO mice compared with wild-type DIO littermates, whereas AdUCP2 i.v. injection restored both EDR and flow-mediated vasodilatation in DIO mice. Improved EDR in mesenteric arteries was inhibited by nitric oxide synthase inhibitor. UCP2 overexpression also inhibited intracellular ROS production in the en face endothelium of aorta and mesenteric artery of DIO mice, whereas UCP2 deficiency enhanced ROS production. CONCLUSIONS UCP2 preserves endothelial function through increasing nitric oxide bioavailability secondary to the inhibition of ROS production in the endothelium of obese diabetic mice.
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Affiliation(s)
- Xiao Yu Tian
- Institute of Vascular Medicine, Hong Kong SAR, China
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Orhan N, Kucukali CI, Cakir U, Seker N, Aydin M. Genetic variants in nuclear-encoded mitochondrial proteins are associated with oxidative stress in obsessive compulsive disorders. J Psychiatr Res 2012; 46:212-8. [PMID: 22070905 DOI: 10.1016/j.jpsychires.2011.09.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 08/04/2011] [Accepted: 09/27/2011] [Indexed: 10/15/2022]
Abstract
Obsessive compulsive disorder is a common psychiatric disorder defined by the presence of obsessive thoughts and repetitive compulsive actions. The mutations or polymorphic variants in mitochondrial DNA-encoded genes or nuclear genes result in oxidative stress, which has recently been associated with various psychiatric disorders. In order to understand the association of mitochondrial disorders with oxidative stress in obsessive compulsive disorder, we examined genetic variants of manganese superoxide dismutase and uncouple-2 antioxidant genes and malondialdehyde and glutathione, markers of oxidative stress. The study sample comprised 104 patients with OCD and 110 healthy controls. For manganese superoxide dismutase, the frequencies of CT (Ala/Val) genotype (p < 0.01) in patients were significantly lower than those of controls. In contrast, CC (Ala/Ala) genotype was significantly more frequent in patients than controls (p < 0.05). For uncouple-2 I/D, the frequencies of ID genotype (p < 0.01) and I allele (p < 0.05) were lower in patients as compared with controls. In contrast, DD genotype was more prevalent in patients than controls (p < 0.01). While whole blood glutathione was significantly diminished (p < 0.0001), serum malondialdehyde was significantly elevated in patients compared with controls (p < 0.0001). Malondialdehyde levels were significantly elevated in subjects with DD genotype of UCP-2 I/D (p < 0.05) and CC genotype of manganese superoxide dismutase (p < 0.05) as compared with II or ID and TT or CT genotype, respectively. Malondialdehyde levels in patients carrying CC (p < 0.05) or CT (p < 0.05) genotype were significantly higher than those of carrying TT genotype. In conclusion, CC genotype of manganese superoxide dismutase or DD genotype of UCP-2 might result in mitochondrial disorders by increasing oxidative stress in obsessive compulsive disorders.
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Affiliation(s)
- Nurcan Orhan
- Department of Neuroscience, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
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Ruiz-Ramírez A, Chávez-Salgado M, Peñeda-Flores JA, Zapata E, Masso F, El-Hafidi M. High-sucrose diet increases ROS generation, FFA accumulation, UCP2 level, and proton leak in liver mitochondria. Am J Physiol Endocrinol Metab 2011; 301:E1198-207. [PMID: 21917631 DOI: 10.1152/ajpendo.00631.2010] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Obesity, a risk factor for insulin resistance, contributes to the development of type 2 diabetes and cardiovascular diseases. The relationship between increased levels of free fatty acids in the liver mitochondria, mitochondrial function, and ROS generation in rat model of obesity induced by a high-sucrose diet was not sufficiently established. We determined how the bioenergetic functions and ROS generation of the mitochondria respond to a hyperlipidemic environment. Mitochondria from sucrose-fed rats generated H(2)O(2) at a higher rate than the control mitochondria. Adding fatty acid-free bovine serum albumin to mitochondria from sucrose-fed rats significantly reduced the rate of H(2)O(2) generation. In contrast, adding exogenous oleic or linoleic acid exacerbated the rate of H(2)O(2) generation in both sucrose-fed and control mitochondria, and the mitochondria from sucrose-fed rats were more sensitive than the control mitochondria. The increased rate of H(2)O(2) generation in sucrose-fed mitochondria corresponded to decreased levels of reduced GSH and vitamin E and increased levels of Cu/Zn-SOD in the intermembrane space. There was no difference between the levels of lipid peroxidation and protein carbonylation in the two types of mitochondria. In addition to the normal activity of Mn-SOD, GPX and catalase detected an increased activity of complex II, and upregulation of UCP2 was observed in mitochondria from sucrose-fed rats, all of which may accelerate respiration rates and reduce generation of ROS. In turn, these effects may protect the mitochondria of sucrose-fed rats from oxidative stress and preserve their function and integrity. However, in whole liver these adaptive mechanisms of the mitochondria were inefficient at counteracting redox imbalances and inhibiting oxidative stress outside of the mitochondria.
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Affiliation(s)
- Angélica Ruiz-Ramírez
- Cardiovascular Biomedicine, Cellular Biology, National Institute of Cardiology Ignacio Chávez, Tlalpan, Mexico
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Glushakova LG, Judge S, Cruz A, Pourang D, Mathews CE, Stacpoole PW. Increased superoxide accumulation in pyruvate dehydrogenase complex deficient fibroblasts. Mol Genet Metab 2011; 104:255-60. [PMID: 21846590 PMCID: PMC3205311 DOI: 10.1016/j.ymgme.2011.07.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 07/22/2011] [Indexed: 01/13/2023]
Abstract
The pyruvate dehydrogenase complex (PDC) oxidizes pyruvate to acetyl CoA and is critically important in maintaining normal cellular energy homeostasis. Loss-of-function mutations in PDC give rise to congenital lactic acidosis and to progressive cellular energy failure. However, the subsequent biochemical consequences of PDC deficiency that may contribute to the clinical manifestations of the disorder are poorly understood. We postulated that altered flux through PDC would disrupt mitochondrial electron transport, resulting in oxidative stress. Compared to cells from 4 healthy subjects, primary cultures of skin fibroblasts from 9 patients with variable mutations in the gene encoding the alpha subunit (E1α) of pyruvate dehydrogenase (PDA1) demonstrated reduced growth and viability. Superoxide (O(2)(.-)) from the Qo site of complex III of the electron transport chain accumulated in these cells and was associated with decreased activity of manganese superoxide dismutase. The expression of uncoupling protein 2 was also decreased in patient cells, but there were no significant changes in the expression of cellular markers of protein or DNA oxidative damage. The expression of hypoxia transcription factor 1 alpha (HIF1α) also increased in PDC deficient fibroblasts. We conclude that PDC deficiency is associated with an increase in O(2)(.-) accumulation coupled to a decrease in mechanisms responsible for its removal. Increased HIF1α expression may contribute to the increase in glycolytic flux and lactate production in PDC deficiency and, by trans-activating pyruvate dehydrogenase kinase, may further suppress residual PDC activity through phosphorylation of the E1α subunit.
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Affiliation(s)
- Lyudmyla G. Glushakova
- Department of Medicine (Division of Endocrinology and Metabolism), College of Medicine, University of Florida, Gainesville, FL, 32611
| | - Sharon Judge
- Department of Medicine (Division of Endocrinology and Metabolism), College of Medicine, University of Florida, Gainesville, FL, 32611
| | - Alex Cruz
- Department of Medicine (Division of Endocrinology and Metabolism), College of Medicine, University of Florida, Gainesville, FL, 32611
| | - Deena Pourang
- Department of Medicine (Division of Endocrinology and Metabolism), College of Medicine, University of Florida, Gainesville, FL, 32611
| | - Clayton E. Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL, 32611
| | - Peter W. Stacpoole
- Department of Medicine (Division of Endocrinology and Metabolism), College of Medicine, University of Florida, Gainesville, FL, 32611
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, 32611
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Wang Q, Zhang M, Liang B, Shirwany N, Zhu Y, Zou MH. Activation of AMP-activated protein kinase is required for berberine-induced reduction of atherosclerosis in mice: the role of uncoupling protein 2. PLoS One 2011; 6:e25436. [PMID: 21980456 PMCID: PMC3181327 DOI: 10.1371/journal.pone.0025436] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 09/05/2011] [Indexed: 12/15/2022] Open
Abstract
AIMS Berberine, a botanical alkaloid purified from Coptidis rhizoma, is reported to activate the AMP-activated protein kinase (AMPK). Whether AMPK is required for the protective effects of berberine in cardiovascular diseases remains unknown. This study was designed to determine whether AMPK is required for berberine-induced reduction of oxidative stress and atherosclerosis in vivo. METHODS ApoE (ApoE⁻/⁻) mice and ApoE⁻/⁻/AMPK alpha 2⁻/⁻ mice that were fed Western diets were treated with berberine for 8 weeks. Atherosclerotic aortic lesions, expression of uncoupling protein 2 (UCP2), and markers of oxidative stress were evaluated in isolated aortas. RESULTS In ApoE⁻/⁻ mice, chronic administration of berberine significantly reduced aortic lesions, markedly reduced oxidative stress and expression of adhesion molecules in aorta, and significantly increased UCP2 levels. In contrast, in ApoE⁻/⁻/AMPK alpha 2⁻/⁻ mice, berberine had little effect on those endpoints. In cultured human umbilical vein endothelial cells (HUVECs), berberine significantly increased UCP2 mRNA and protein expression in an AMPK-dependent manner. Transfection of HUVECs with nuclear respiratory factor 1 (NRF1)-specific siRNA attenuated berberine-induced expression of UCP2, whereas transfection with control siRNA did not. Finally, berberine promoted mitochondrial biogenesis that contributed to up-regulation of UCP2 expression. CONCLUSION We conclude that berberine reduces oxidative stress and vascular inflammation, and suppresses atherogenesis via a mechanism that includes stimulation of AMPK-dependent UCP2 expression.
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Affiliation(s)
- Qilong Wang
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Miao Zhang
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Bin Liang
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Najeeb Shirwany
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Yi Zhu
- Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China
| | - Ming-Hui Zou
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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Widlansky ME, Gutterman DD. Regulation of endothelial function by mitochondrial reactive oxygen species. Antioxid Redox Signal 2011; 15:1517-30. [PMID: 21194353 PMCID: PMC3151425 DOI: 10.1089/ars.2010.3642] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Revised: 12/07/2010] [Accepted: 01/01/2011] [Indexed: 12/19/2022]
Abstract
Mitochondria are well known for their central roles in ATP production, calcium homeostasis, and heme and steroid biosynthesis. However, mitochondrial reactive oxygen species (ROS), including superoxide and hydrogen peroxide, once thought to be toxic byproducts of mitochondrial physiologic activities, have recently been recognized as important cell-signaling molecules in the vascular endothelium, where their production, conversion, and destruction are highly regulated. Mitochondrial reactive oxygen species appear to regulate important vascular homeostatic functions under basal conditions in a variety of vascular beds, where, in particular, they contribute to endothelium-dependent vasodilation. On exposure to cardiovascular risk factors, endothelial mitochondria produce excessive ROS in concert with other cellular ROS sources. Mitochondrial ROS, in this setting, act as important signaling molecules activating prothrombotic and proinflammatory pathways in the vascular endothelium, a process that initially manifests itself as endothelial dysfunction and, if persistent, may lead to the development of atherosclerotic plaques. This review concentrates on emerging appreciation of the importance of mitochondrial ROS as cell-signaling molecules in the vascular endothelium under both physiologic and pathophysiologic conditions. Future potential avenues of research in this field also are discussed.
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Affiliation(s)
- Michael E Widlansky
- Department of Medicine, Cardiovascular Medicine Division and Department of Pharmacology, Medical College of Wisconsin , Milwaukee, Wisconsin
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Kuhla A, Trieglaff C, Vollmar B. Role of age and uncoupling protein-2 in oxidative stress, RAGE/AGE interaction and inflammatory liver injury. Exp Gerontol 2011; 46:868-76. [PMID: 21820503 DOI: 10.1016/j.exger.2011.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 05/23/2011] [Accepted: 07/19/2011] [Indexed: 01/12/2023]
Abstract
The objective of this study is to clarify whether age-related oxidative stress enhances hepatic vulnerability via increased interaction of advanced glycation endproducts (AGE) with their receptor RAGE. To further address the role of uncoupling of mitochondrial respiration, mitochondrial uncoupling protein-2 wild-type (UCP2+/+) and knock out (UCP2-/-) mice were used and studied at an age of 8 (young), 38 (adult) and 76 weeks (senescent). First, we could show that UCP2 protein expression increased with age in UCP2+/+ mice. Second, in both mouse strains oxidative stress, as measured by malondialdehyde concentrations and the ratio of glutathione to glutathione disulfide, as well as hepatic RAGE expression and highly modified AGE accumulation significantly increased with age. This, however, was far more pronounced in UCP2-/- mice, in particular at the young age of 8 wk. In addition, the hepatic activity of the AGE precursor detoxifying enzyme glyoxalase-I was significantly decreased in 8 wk old UCP2-/- animals and concomitantly caused 2-fold higher levels of methylglyoxal-modified AGE in these animals. We further showed that the numbers of hepatic cells expressing sRAGE which acts as a decoy for RAGE ligands decreased with age and were markedly lower in the UCP2-/- than the UCP2+/+ mice. As a consequence, young 8 wk old UCP2-/- mice benefited from treatment with recombinant mouse RAGE to block the RAGE/AGE interaction, when challenged with galactosamine/lipopolysaccharide for the induction of acute liver injury. They showed less pronounced tissue damage and slightly lower mortality rate, while older UCP2+/+ and UCP2-/- mice revealed comparably high mortality rates and extent of liver injury, irrespective of their treatment with rRAGE. Taken together, the present study underlines the role of UCP2 in the age-related increase of oxidative stress and the oxidative stress-related RAGE/AGE interaction. In young animals, blockade of the RAGE/AGE interaction is of benefit, while in older animals, this protective effect is lost, supposedly due to the fact that with age other factors than enhanced hepatic glycation products predominantly determine liver injury and injury-related mortality rate.
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Affiliation(s)
- Angela Kuhla
- Institute for Experimental Surgery, University of Rostock, Schillingallee 69a, Rostock, Germany
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Xu MJ, Song P, Shirwany N, Liang B, Xing J, Viollet B, Wang X, Zhu Y, Zou MH. Impaired expression of uncoupling protein 2 causes defective postischemic angiogenesis in mice deficient in AMP-activated protein kinase α subunits. Arterioscler Thromb Vasc Biol 2011; 31:1757-65. [PMID: 21597006 DOI: 10.1161/atvbaha.111.227991] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE The aim of the present study was to determine whether mitochondrial uncoupling protein (UCP) 2 is required for AMPK-dependent angiogenesis in ischemia in vivo. METHODS AND RESULTS Angiogenesis was assayed by monitoring endothelial tube formation (a surrogate for angiogenesis) in human umbilical vein endothelial cells (ECs), isolated mouse aortic endothelial cells (MAECs), and pulmonary microvascular endothelial cells or in ischemic thigh adductor muscles from wild-type (WT) mice or mice deficient in either AMPKα1 or AMPKα2. AMPK inhibition with pharmacological inhibitor (compound C) or genetic means (transfection of AMPKα-specific small interfering RNA) significantly lowered the tube formation in human umbilical vein ECs. Consistently, compared with WT mice, tube formation in MAECs isolated from either AMPKα1(-/-) or AMPKα2(-/-) mice, which exhibited oxidative stress and reduced expression of UCP2, was significantly impaired. In addition, adenoviral overexpression of UCP2, but not adenoviruses encoding green fluorescent protein, normalized tube formation in MAECs from either AMPKα1(-/-) or AMPKα2(-/-) mice. Similarly, supplementation with sodium nitroprusside, a nitric oxide (NO) donor, restored tube formation. Furthermore, ischemia significantly increased angiogenesis, serine 1177 phosphorylation of endothelial NO synthase, and UCP2 in ischemic thigh adductor muscles from WT mice but not in those from either AMPKα1(-/-) or AMPKα2(-/-) mice. CONCLUSIONS We conclude that AMPK-dependent UCP2 expression in ECs promotes angiogenesis in vivo.
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Affiliation(s)
- Ming-Jiang Xu
- Section of Molecular Medicine, Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, 73104, USA
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Schiff M, Bénit P, Coulibaly A, Loublier S, El-Khoury R, Rustin P. Mitochondrial response to controlled nutrition in health and disease. Nutr Rev 2011; 69:65-75. [PMID: 21294740 DOI: 10.1111/j.1753-4887.2010.00363.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Mitochondria exert crucial physiological functions that create complex links among nutrition, health, and disease. While mitochondrial dysfunction with subsequent impairment of oxidative phosphorylation (OXPHOS) is the hallmark of the rare inherited OXPHOS diseases, OXPHOS dysfunction also plays a central role in the pathophysiology of common conditions such as type 2 diabetes and various neurodegenerative disorders. Dietary interventions, especially calorie restriction, have been shown to improve the course of these diseases and to extend the lifespan. Few data are available on the impact of nutraceuticals (macronutrients, vitamins, and cofactors) on primary inherited OXPHOS diseases. This review presents recent knowledge about the impact of nutritional modulation on mitochondria and lifespan regulation and about the development of potential treatments for mitochondrial dysfunction diseases.
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Affiliation(s)
- Manuel Schiff
- Centre de référence Maladies Métaboliques, Hôpital Robert Debré, APHP, Université Paris 7, Faculté de médecine Denis Diderot, IFR02, INSERM, U676, Paris, France.
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Joo JI, Kim DH, Choi JW, Yun JW. Proteomic analysis for antiobesity potential of capsaicin on white adipose tissue in rats fed with a high fat diet. J Proteome Res 2010; 9:2977-87. [PMID: 20359164 DOI: 10.1021/pr901175w] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
It is well recognized that capsaicin increases thermogenesis through enhancement of catecholamine secretion from the adrenal medulla. In the present study of the antiobesity effect of capsaicin, rats (5-week old) received capsaicin (10 mg/kg) along with a high-fat diet (HFD). In comparison with saline-treated rats, body weight of those in the capsaicin-treated group decreased by 8%. We performed differential proteomic analysis using two-dimensional electrophoresis (2-DE) combined with MALDI-TOF mass spectrometry to elucidate the molecular action of capsaicin on the antiobesity effect in epididymal white adipose tissue (WAT). Protein mapping of WAT homogenates using 2-DE revealed significant alterations to a number of proteins: 10 spots were significantly up-regulated and 10 spots were remarkably down-regulated in HFD fed rats treated with capsaicin. Among them, significant down-regulation of heat shock protein 27 (Hsp27) and Steap3 protein, as well as up-regulation of olfactory receptor (Olr1434) in obese WAT was reported for the first time in association with obesity. Most of the identified proteins are associated with lipid metabolism and redox regulation, in which levels of vimentin, peroxiredoxin, and NAD(P)H:quinone oxidoreductase 1 (NQO1) were significantly reduced (>2-fold), whereas aldo-keto reductase, flavoprotein increased with capsaicin treatment. These data demonstrate that thermogenesis and lipid metabolism related proteins were markedly altered upon capsaicin treatment in WAT, suggesting that capsaicin may be a useful phytochemical for attenuation of obesity.
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Affiliation(s)
- Jeong In Joo
- Department of Biotechnology, Daegu University, Kyungbuk, Korea
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Correia SC, Santos RX, Perry G, Zhu X, Moreira PI, Smith MA. Mitochondria: the missing link between preconditioning and neuroprotection. J Alzheimers Dis 2010; 20 Suppl 2:S475-85. [PMID: 20463394 DOI: 10.3233/jad-2010-100669] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The quote "what does not kill you makes you stronger" perfectly describes the preconditioning phenomenon - a paradigm that affords robust brain tolerance in the face of neurodegenerative insults. Over the last few decades, many attempts have been made to identify the molecular mechanisms involved in preconditioning-induced protective responses, and recent data suggests that many of these mechanisms converge on the mitochondria, positing mitochondria as master regulators of preconditioning-triggered endogenous neuroprotection. In this review, we critically discuss evidence for the involvement of mitochondria within the preconditioning paradigm. We will highlight the crucial targets and mediators by which mitochondria are integrated into neuroprotective signaling pathways that underlie preconditioning, putting focus on mitochondrial respiratory chain and mitochondrial reactive oxygen species, mitochondrial ATP-sensitive potassium channels, mitochondrial permeability transition pore, uncoupling proteins, and mitochondrial antioxidant enzyme manganese superoxide dismutase. We also discuss the role of mitochondria in the induction of hypoxia-inducible factor-1, a transcription factor engaged in preconditioning-mediated neuroprotective effects. The identification of intrinsic mitochondrial mechanisms involved in preconditioning will provide new insights which can be translated into potential pharmacological interventions aimed at counteracting neurodegeneration.
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Affiliation(s)
- Sónia C Correia
- Center for Neuroscience and Cell Biology of Coimbra, University of Coimbra, Coimbra, Portugal
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Kuhla A, Hettwer C, Menger MD, Vollmar B. Oxidative stress-associated rise of hepatic protein glycation increases inflammatory liver injury in uncoupling protein-2 deficient mice. J Transl Med 2010; 90:1189-98. [PMID: 20368701 DOI: 10.1038/labinvest.2010.84] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Mitochondrial dysfunction seems to be intrinsically involved in the pathogenesis of multiple organ failure because of enhanced production of reactive oxygen species and induction of oxidative damage. Chronic oxidative stress in turn causes an accumulation of advanced glycation end products (AGEs). To investigate whether mitochondrial dysfunction-associated oxidative stress leads to increased formation and accumulation of AGE, we studied hepatic glycation in uncoupling protein-2 (UCP2-/-) knockout mice. Using the galactosamine/lipopolysaccharide (G/L)-induced liver injury model, we further tested the hypothesis that a mitochondrial dysfunction-associated increase of hepatic glycation is causative for increased liver injury. Under baseline conditions, UCP2-/- mice showed higher malondialdehyde levels and reduced glutathione/glutathione disulfide ratios as well as significantly higher hepatic levels of AGE and hepatic expression of receptor for AGE (RAGE) when compared with UCP2+/+ mice, indicative for increased oxidative stress and hepatic glycation. Further, livers of G/L-challenged UCP2-/- mice revealed significantly more pronounced tissue injury and were found to express higher levels of AGE and RAGE compared with wild-type mice. Functional blockade of RAGE by application of recombinant RAGE significantly diminished liver damage particularly in UCP2-/- mice. This in turn increased survival from 30% in UCP2+/+ mice to 50% in UCP2-/- mice. In summary, we show for the first time that mitochondrial dysfunction-associated oxidative stress enhances hepatic protein glycation, which aggravates inflammation-induced liver injury. Targeting the AGE/RAGE interaction by the blockade of RAGE might be of therapeutic value for the oxidative stress-exposed liver.
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Affiliation(s)
- Angela Kuhla
- Institute for Experimental Surgery, University of Rostock, Rostock, Germany
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