51
|
Demeter-Haludka V, Kovács M, Petrus A, Patai R, Muntean DM, Siklós L, Végh Á. Examination of the Role of Mitochondrial Morphology and Function in the Cardioprotective Effect of Sodium Nitrite Administered 24 h Before Ischemia/Reperfusion Injury. Front Pharmacol 2018; 9:286. [PMID: 29643809 PMCID: PMC5882827 DOI: 10.3389/fphar.2018.00286] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 03/13/2018] [Indexed: 11/13/2022] Open
Abstract
Background: We have previous evidence that in anesthetized dogs the inorganic sodium nitrite protects against the severe ventricular arrhythmias, resulting from coronary artery occlusion and reperfusion, when administered 24 h before. The present study aimed to examine, whether in this effect changes in mitochondrial morphology and function would play a role. Methods: Thirty dogs were infused intravenously either with saline (n = 15) or sodium nitrite (0.2 μmol/kg/min; n = 15) for 20 min, and 24 h later, 10 dogs from each group were subjected to a 25 min period of occlusion and then reperfusion of the left anterior descending coronary artery. The severity of ischaemia and ventricular arrhythmias were examined in situ. Left ventricular tissue samples were collected either before the occlusion (5 saline and 5 nitrite treated dogs) or, in dogs subjected to occlusion, 2 min after reperfusion. Changes in mitochondrial morphology, in complex I and complex II-dependent oxidative phosphorylation (OXPHOS), in ATP, superoxide, and peroxynitrite productions were determined. Results: The administration of sodium nitrite 24 h before ischemia/reperfusion significantly attenuated the severity of ischaemia, and markedly reduced the number and incidence of ventricular arrhythmias. Nitrite also attenuated the ischaemia and reperfusion (I/R)-induced structural alterations, such as reductions in mitochondrial area, perimeter, and Feret diameter, as well as the increase in mitochondrial roundness. The administration of nitrite, however, enhanced the I/R-induced reduction in the mitochondrial respiratory parameters; compared to the controls, 24 h after the infusion of nitrite, there were further significant decreases, e.g., in the complex I-dependent OXPHOS (by -20 vs. -53%), respiratory control ratio (by -14 vs. -61%) and in the P/E control coupling ratio (by 2 vs. -36%). Nitrite also significantly reduced the I/R-induced generation of superoxide, without substantially influencing the ATP production. Conclusions: The results suggest that sodium nitrite may have an effect on the mitochondria; it preserves the mitochondrial structure and modifies the mitochondrial function, when administered 24 h prior to I/R. We propose that nitrite affects primary the phosphorylation system (indicated by the decreased P/E ratio), and the reduction in superoxide production would result from the subsequent suppression of the ROS producing complexes; an effect which may certainly contribute to the antiarrhythmic effect of nitrite.
Collapse
Affiliation(s)
- Vivien Demeter-Haludka
- Department of Pharmacology and Pharmacotherapy, Albert-Szent Györgyi Medical Centre, University of Szeged, Szeged, Hungary
| | - Mária Kovács
- Department of Pharmacology and Pharmacotherapy, Albert-Szent Györgyi Medical Centre, University of Szeged, Szeged, Hungary
| | - Alexandra Petrus
- Department of Pathophysiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - Roland Patai
- Department of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Danina M Muntean
- Department of Pathophysiology, "Victor Babes" University of Medicine and Pharmacy, Timisoara, Romania
| | - László Siklós
- Department of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Ágnes Végh
- Department of Pharmacology and Pharmacotherapy, Albert-Szent Györgyi Medical Centre, University of Szeged, Szeged, Hungary
| |
Collapse
|
52
|
Protective effects of mitochondrion-targeted peptide SS-31 against hind limb ischemia-reperfusion injury. J Physiol Biochem 2018; 74:335-343. [PMID: 29589186 DOI: 10.1007/s13105-018-0617-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 02/16/2018] [Indexed: 12/11/2022]
Abstract
Hind limb ischemia-reperfusion injury is an important pathology in vascular surgery. Reactive oxygen species are thought to be involved in the pathogenesis of hind limb ischemia-reperfusion injury. SS-31, which belongs to a family of mitochondrion-targeted peptide antioxidants, was shown to reduce mitochondrial reactive oxygen species production. In this study, we investigated whether the treatment of SS-31 could protect hind limb from ischemia-reperfusion injury in a mouse model. The results showed that SS-31 treatment either before or after ischemia exhibited similar protective effects. Histopathologically, SS-31 treatment prevented the IR-induced histological deterioration compared with the corresponding vehicle control. SS-31 treatment diminished oxidative stress revealed by the reduced malondialdehyde level and increased activities and protein levels of Sod and catalase. Cellular ATP contents and mitochondrial membrane potential increased and the level of cytosolic cytC was decreased after SS-31 treatment in this IR model, demonstrating that mitochondria were protected. The IR-induced increase of levels of inflammatory factors, such as Tnf-α and Il-1β, was prevented by SS-31 treatment. In agreement with the reduced cytosolic cytC, cleaved-caspase 3 was kept at a very low level after SS-31 treatment. Overall, the effect of SS-31 treatment before ischemia is mildly more effective than that after ischemia. In conclusion, our results demonstrate that SS-31 confers a protective effect in the mouse model of hind limb ischemia-reperfusion injury preventatively and therapeutically.
Collapse
|
53
|
Krebs cycle metabolites and preferential succinate oxidation following neonatal hypoxic-ischemic brain injury in mice. Pediatr Res 2018; 83:491-497. [PMID: 29211056 PMCID: PMC5866163 DOI: 10.1038/pr.2017.277] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 10/14/2017] [Indexed: 01/25/2023]
Abstract
BackgroundReverse electron transport (RET) driven by the oxidation of succinate has been proposed as the mechanism of accelerated production of reactive oxygen species (ROS) in post-ischemic mitochondria. However, it remains unclear whether upon reperfusion, mitochondria preferentially oxidase succinate.MethodsNeonatal mice were subjected to Rice-Vannucci model of hypoxic-ischemic brain injury (HI) followed by assessment of Krebs cycle metabolites, mitochondrial substrate preference, and H2O2 generation rate in the ischemic brain.ResultsWhile brain mitochondria from control mice exhibited a rotenone-sensitive complex-I-dependent respiration, HI-brain mitochondria, at the initiation of reperfusion, demonstrated complex-II-dependent respiration, as rotenone minimally affected, but inhibition of complex-II ceased respiration. This was associated with a 30-fold increase of cerebral succinate concentration and significantly elevated H2O2 emission rate in HI-mice compared to controls. At 60 min of reperfusion, cerebral succinate content and the mitochondrial response to rotenone did not differ from that in controls.ConclusionThese data are the first ex vivo evidence, that at the initiation of reperfusion, brain mitochondria transiently shift their metabolism from complex-I-dependent oxidation of NADH toward complex II-linked oxidation of succinate. Our study provides a critical piece of support for existence of the RET-dependent mechanism of elevated ROS production in reperfusion.
Collapse
|
54
|
Chen Q, Younus M, Thompson J, Hu Y, Hollander JM, Lesnefsky EJ. Intermediary metabolism and fatty acid oxidation: novel targets of electron transport chain-driven injury during ischemia and reperfusion. Am J Physiol Heart Circ Physiol 2017; 314:H787-H795. [PMID: 29351463 DOI: 10.1152/ajpheart.00531.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cardiac ischemia-reperfusion (I/R) damages the electron transport chain (ETC), causing mitochondrial and cardiomyocyte injury. Reversible blockade of the ETC at complex I during ischemia protects the ETC and decreases cardiac injury. In the present study, we used an unbiased proteomic approach to analyze the extent of ETC-driven mitochondrial injury during I/R. Isolated-perfused mouse (C57BL/6) hearts underwent 25-min global ischemia (37°C) and 30-min reperfusion. In treated hearts, amobarbital (2 mM) was given for 1 min before ischemia to rapidly and reversibly block the ETC at complex I. Mitochondria were isolated at the end of reperfusion and subjected to unbiased proteomic analysis using tryptic digestion followed by liquid chromatography-mass spectrometry with isotope tags for relative and absolute quantification. Amobarbital treatment decreased cardiac injury and protected respiration. I/R decreased the content ( P < 0.05) of multiple mitochondrial matrix enzymes involved in intermediary metabolism compared with the time control. The contents of several enzymes in fatty acid oxidation were decreased compared with the time control. Blockade of ETC during ischemia largely prevented the decreases. Thus, after I/R, not only the ETC but also multiple pathways of intermediary metabolism sustain damage initiated by the ETC. If these damaged mitochondria persist in the myocyte, they remain a potent stimulus for ongoing injury and the transition to cardiomyopathy during prolonged reperfusion. Modulation of ETC function during early reperfusion is a key strategy to preserve mitochondrial metabolism and to decrease persistent mitochondria-driven injury during longer periods of reperfusion that predispose to ventricular dysfunction and heart failure. NEW & NOTEWORTHY Ischemia-reperfusion (I/R) damages mitochondria, which could be protected by reversible blockade of the electron transport chain (ETC). Unbiased proteomics with isotope tags for relative and absolute quantification analyzed mitochondrial damage during I/R and found that multiple enzymes in the tricarboxylic acid cycle, fatty acid oxidation, and ETC decreased, which could be prevented by ETC blockade. Strategic ETC modulation can reduce mitochondrial damage and cardiac injury.
Collapse
Affiliation(s)
- Qun Chen
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University , Richmond, Virginia
| | - Masood Younus
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University , Richmond, Virginia
| | - Jeremy Thompson
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University , Richmond, Virginia
| | - Ying Hu
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University , Richmond, Virginia
| | - John M Hollander
- Division of Exercise Physiology, Mitochondria, Metabolism, and Bioenergetics Working Group, West Virginia University , Morgantown, West Virginia
| | - Edward J Lesnefsky
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University , Richmond, Virginia.,Department of Biochemistry and Molecular Biology, Virginia Commonwealth University , Richmond, Virginia.,Department of Physiology and Biophysics, Virginia Commonwealth University , Richmond, Virginia.,McGuire Department of Veterans Affairs Medical Center , Richmond, Virginia
| |
Collapse
|
55
|
Sánchez-Ramos C, Prieto I, Tierrez A, Laso J, Valdecantos MP, Bartrons R, Roselló-Catafau J, Monsalve M. PGC-1α Downregulation in Steatotic Liver Enhances Ischemia-Reperfusion Injury and Impairs Ischemic Preconditioning. Antioxid Redox Signal 2017; 27:1332-1346. [PMID: 28269997 DOI: 10.1089/ars.2016.6836] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
AIMS Liver steatosis is associated with mitochondrial dysfunction and elevated reactive oxygen species (ROS) levels together with enhanced sensitivity to ischemia-reperfusion (IR) injury and limited response to preconditioning protocols. Here, we sought to determine whether the downregulation in the steatotic liver of peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), a master regulator of mitochondrial metabolism and ROS that is known to play a role in liver metabolic control, could be responsible for the sensitivity of the steatotic liver to ischemic damage. RESULTS PGC-1α was induced in normal liver after exposure to an IR protocol, which was concomitant with an increase in the levels of antioxidant proteins. By contrast, its induction was severely blunted in the steatotic liver, resulting in a modest induction of antioxidant proteins. Livers of PGC-1α-/- mice on a chow diet were normal, but they exhibited an enhanced sensitivity to IR injury and also a lack of response to ischemic preconditioning (IPC), a phenotype that recapitulated the features of the steatotic liver in terms of liver damage, although the inflammatory response differed between both models. Utilizing an in vitro model of IPC, we found that PGC-1α expression was downregulated in hepatic cells cultured at 1% O2; whereas it was induced after reoxygenation (3% O2), and it was responsible for the recovery of antioxidant gene expression after the ischemic period. Innovation & Conclusion: PGC-1α plays an important role in the protection against IR injury in the liver, which is likely associated with its capacity to induce antioxidant gene expression. Antioxid. Redox Signal. 27, 1332-1346.
Collapse
Affiliation(s)
| | - Ignacio Prieto
- 1 Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM) , Madrid, Spain
| | - Alberto Tierrez
- 2 Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) , Madrid, Spain
| | - Javier Laso
- 2 Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) , Madrid, Spain
| | - M Pilar Valdecantos
- 3 Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERdem) , ISCIII, Madrid, Spain
| | - Ramon Bartrons
- 4 Unitat de Bioquímica i Biologia Molecular, Departament de Ciències Fisiològiques, Campus de Bellvitge, IDIBELL-Universitat de Barcelona , Hospitalet, Spain
| | - Joan Roselló-Catafau
- 5 Experimental Hepatic Ischemia-Reperfusion Unit, Institut d'Investigacions Biomèdiques de Barcelona (CSIC) , Barcelona, Spain
| | - María Monsalve
- 1 Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM) , Madrid, Spain
| |
Collapse
|
56
|
Hou WL, Yin J, Alimujiang M, Yu XY, Ai LG, Bao YQ, Liu F, Jia WP. Inhibition of mitochondrial complex I improves glucose metabolism independently of AMPK activation. J Cell Mol Med 2017; 22:1316-1328. [PMID: 29106036 PMCID: PMC5783883 DOI: 10.1111/jcmm.13432] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Accepted: 09/22/2017] [Indexed: 12/27/2022] Open
Abstract
Accumulating evidences showed metformin and berberine, well‐known glucose‐lowering agents, were able to inhibit mitochondrial electron transport chain at complex I. In this study, we aimed to explore the antihyperglycaemic effect of complex I inhibition. Rotenone, amobarbital and gene silence of NDUFA13 were used to inhibit complex I. Intraperitoneal glucose tolerance test and insulin tolerance test were performed in db/db mice. Lactate release and glucose consumption were measured to investigate glucose metabolism in HepG2 hepatocytes and C2C12 myotubes. Glucose output was measured in primary hepatocytes. Compound C and adenoviruses expressing dominant negative AMP‐activated protein kinase (AMPK) α1/2 were exploited to inactivate AMPK pathway. Cellular NAD+/NADH ratio was assayed to evaluate energy transforming and redox state. Rotenone ameliorated hyperglycaemia and insulin resistance in db/db mice. It induced glucose consumption and glycolysis and reduced hepatic glucose output. Rotenone also activated AMPK. Furthermore, it remained effective with AMPK inactivation. The enhanced glycolysis and repressed gluconeogenesis correlated with a reduction in cellular NAD+/NADH ratio, which resulted from complex I suppression. Amobarbital, another representative complex I inhibitor, stimulated glucose consumption and decreased hepatic glucose output in vitro, too. Similar changes were observed while expression of NDUFA13, a subunit of complex I, was knocked down with gene silencing. These findings reveal mitochondrial complex I emerges as a key drug target for diabetes treatment. Inhibition of complex I improves glucose homoeostasis via non‐AMPK pathway, which may relate to the suppression of the cellular NAD+/NADH ratio.
Collapse
Affiliation(s)
- Wo-Lin Hou
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China.,Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Diabetes Institute, Shanghai, China
| | - Jun Yin
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China.,Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Diabetes Institute, Shanghai, China
| | - Miriayi Alimujiang
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Diabetes Institute, Shanghai, China
| | - Xue-Ying Yu
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Diabetes Institute, Shanghai, China
| | - Li-Gen Ai
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China
| | - Yu-Qian Bao
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China
| | - Fang Liu
- Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.,Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China
| | - Wei-Ping Jia
- Shanghai Clinical Center for Diabetes, Shanghai Clinical Center for Metabolic Diseases, Shanghai, China.,Shanghai Key Laboratory of Diabetes Mellitus, Shanghai Diabetes Institute, Shanghai, China
| |
Collapse
|
57
|
Andrienko TN, Pasdois P, Pereira GC, Ovens MJ, Halestrap AP. The role of succinate and ROS in reperfusion injury - A critical appraisal. J Mol Cell Cardiol 2017; 110:1-14. [PMID: 28689004 PMCID: PMC5678286 DOI: 10.1016/j.yjmcc.2017.06.016] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/14/2017] [Accepted: 06/30/2017] [Indexed: 12/20/2022]
Abstract
We critically assess the proposal that succinate-fuelled reverse electron flow (REF) drives mitochondrial matrix superoxide production from Complex I early in reperfusion, thus acting as a key mediator of ischemia/reperfusion (IR) injury. Real-time surface fluorescence measurements of NAD(P)H and flavoprotein redox state suggest that conditions are unfavourable for REF during early reperfusion. Furthermore, rapid loss of succinate accumulated during ischemia can be explained by its efflux rather than oxidation. Moreover, succinate accumulation during ischemia is not attenuated by ischemic preconditioning (IP) despite powerful cardioprotection. In addition, measurement of intracellular reactive oxygen species (ROS) during reperfusion using surface fluorescence and mitochondrial aconitase activity detected major increases in ROS only after mitochondrial permeability transition pore (mPTP) opening was first detected. We conclude that mPTP opening is probably triggered initially by factors other than ROS, including increased mitochondrial [Ca2+]. However, IP only attenuates [Ca2+] increases later in reperfusion, again after initial mPTP opening, implying that IP regulates mPTP opening through additional mechanisms. One such is mitochondria-bound hexokinase 2 (HK2) which dissociates from mitochondria during ischemia in control hearts but not those subject to IP. Indeed, there is a strong correlation between the extent of HK2 loss from mitochondria during ischemia and infarct size on subsequent reperfusion. Mechanisms linking HK2 dissociation to mPTP sensitisation remain to be fully established but several related processes have been implicated including VDAC1 oligomerisation, the stability of contact sites between the inner and outer membranes, cristae morphology, Bcl-2 family members and mitochondrial fission proteins such as Drp1.
Collapse
Affiliation(s)
- Tatyana N Andrienko
- School of Biochemistry and The Bristol Heart Institute, Medical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Philippe Pasdois
- School of Biochemistry and The Bristol Heart Institute, Medical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Gonçalo C Pereira
- School of Biochemistry and The Bristol Heart Institute, Medical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Matthew J Ovens
- School of Biochemistry and The Bristol Heart Institute, Medical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Andrew P Halestrap
- School of Biochemistry and The Bristol Heart Institute, Medical Sciences Building, University of Bristol, Bristol BS8 1TD, UK.
| |
Collapse
|
58
|
Guo Y, Li Z, Shi C, Li J, Yao M, Chen X. Trichostatin A attenuates oxidative stress-mediated myocardial injury through the FoxO3a signaling pathway. Int J Mol Med 2017; 40:999-1008. [PMID: 28849190 PMCID: PMC5593460 DOI: 10.3892/ijmm.2017.3101] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 08/03/2017] [Indexed: 11/06/2022] Open
Abstract
Trichostatin A (TSA), a histone deacetylase inhibitor, is widely used as an anticancer drug. Recently, TSA has been shown to exert a protective effect on ischemia/reperfusion (I/R) injury; however, the underlying mechanisms remain unclear. Forkhead box O3a (FoxO3a), a unique FoxO family member, has been shown to attenuate myocardial injury by increasing resistance to oxidative stress in mice. The present study aimed to investigate whether TSA exerts its cardioprotective effects through the FoxO3a signaling pathway. For this purpose, healthy male Wistar rats were pre-treated with TSA for 5 days before they were subjected to ligation/relaxation of the left anterior descending branch of the coronary artery and to 30 min of ischemia, followed by 24 h of reperfusion. The activities of creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and superoxide diamutase (SOD), as well as the malondialdehyde (MDA) levels were examined. The H9c2 rat myocardial cell line was cultured in 10% FBS-containing DMEM for 24 h. The cells were incubated with/without TSA (50 nmol/l) for 1 h and then incubated with/without H2O2 (400 µM) for 2 h. Reactive oxygen species (ROS) and mitochondrial membrane potential (Δψm) were measured by probe staining in the H9c2 cells. The expression of FoxO3a, mitochondrial SOD2 and catalase was quantified by western blot analysis. The levels of H3 and H4 acetylation of the FoxO3a promoter region were examined by chromatin immunoprecipitation assay. TSA significantly reduced the myocardial infarct size and the activities of serum LDH, AST and CK in the rats. TSA also decreased the levels of MDA and increased the activities of SOD in the myocardial tissue of the rats. Consistent with the reduced injury to the TSA-treated rats, TSA significantly reduced the H2O2-induced levels of ROS and increased Δψm. In addition, TSA increased the expression of FoxO3a, SOD2 and catalase, which may be related to increasing the level of H4 acetylation of the FoxO3a promoter region. Our results thus revealed that TSA protected the myocardium from oxidative stress-mediated damage by increasing H4 acetylation of the FoxO3a promoter region, and the expression of FoxO3a, SOD2 and catalase.
Collapse
Affiliation(s)
- Yunhui Guo
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Zhiping Li
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Canxia Shi
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Jia Li
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Meng Yao
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| | - Xia Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin 130021, P.R. China
| |
Collapse
|
59
|
Garvin AM, Aurigemma NC, Hackenberger JL, Korzick DH. Age and ischemia differentially impact mitochondrial ultrastructure and function in a novel model of age-associated estrogen deficiency in the female rat heart. Pflugers Arch 2017; 469:1591-1602. [PMID: 28776263 DOI: 10.1007/s00424-017-2034-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/10/2017] [Accepted: 07/11/2017] [Indexed: 12/19/2022]
Abstract
Altered mitochondrial respiration, morphology, and quality control collectively contribute to mitochondrial dysfunction in the aged heart. Because myocardial infarction remains the leading cause of death in aged women, the present study utilized a novel rodent model to recapitulate human menopause to interrogate the combination of age and estrogen deficiency on mitochondrial ultrastructure and function with cardiac ischemia/reperfusion (I/R) injury. Female F344 rats were ovariectomized (OVX) at 15 months and studied at 24 months (MO OVX; n = 40) vs adult ovary intact (6 months; n = 41). Temporal declines in estrogen concomitant with increased visceral adipose tissue were observed in MO OVX vs adult. Following in vivo coronary artery ligation or sham surgery, state 3 mitochondrial respiration was selectively reduced by age in subsarcolemmal mitochondria (SSM) and by I/R in interfibrillar mitochondria (IFM); left ventricular maximum dP/dt was reduced in MO OVX (p < 0.05). Elevated cyclophilin D and exacerbated I/R-induced mitochondrial acetylation in MO OVX suggest permeability transition pore involvement and reduced protection vs adult (p < 0.05). Mitochondrial morphology by TEM revealed an altered time course of autophagy coordinate with attenuated Drp1 and LC3BII protein levels with age-associated estrogen loss (p < 0.05). Here, reductions in both SSM and IFM function may play an additive role in enhanced susceptibility to regional I/R injury in aged estrogen-deficient female hearts. Moreover, novel insight into altered cardiac mitochondrial quality control garnered here begins to unravel the potentially important regulatory role of mitochondrial dynamics on sustaining respiratory function in the aged female heart.
Collapse
Affiliation(s)
- Alexandra M Garvin
- Intercollege Graduate Degree Program in Physiology, The Pennsylvania State University, 106 Noll Laboratory, University Park, PA, 16802, USA
| | - Nicole C Aurigemma
- Intercollege Graduate Degree Program in Physiology, The Pennsylvania State University, 106 Noll Laboratory, University Park, PA, 16802, USA
| | - Jenna L Hackenberger
- Department of Kinesiology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Donna H Korzick
- Intercollege Graduate Degree Program in Physiology, The Pennsylvania State University, 106 Noll Laboratory, University Park, PA, 16802, USA. .,Department of Kinesiology, The Pennsylvania State University, University Park, PA, 16802, USA.
| |
Collapse
|
60
|
Aqueous extract of Cortex Dictamni protects H9c2 cardiomyocytes from hypoxia/reoxygenation-induced oxidative stress and apoptosis by PI3K/Akt signaling pathway. Biomed Pharmacother 2017; 89:233-244. [DOI: 10.1016/j.biopha.2017.02.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/07/2017] [Accepted: 02/07/2017] [Indexed: 12/13/2022] Open
|
61
|
Korge P, Calmettes G, John SA, Weiss JN. Reactive oxygen species production induced by pore opening in cardiac mitochondria: The role of complex III. J Biol Chem 2017; 292:9882-9895. [PMID: 28450391 DOI: 10.1074/jbc.m116.768317] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/14/2017] [Indexed: 01/02/2023] Open
Abstract
Recent evidence has implicated succinate-driven reverse electron transport (RET) through complex I as a major source of damaging reactive oxygen species (ROS) underlying reperfusion injury after prolonged cardiac ischemia. However, this explanation may be incomplete, because RET on reperfusion is self-limiting and therefore transient. RET can only generate ROS when mitochondria are well polarized, and it ceases when permeability transition pores (PTP) open during reperfusion. Because prolonged ischemia/reperfusion also damages electron transport complexes, we investigated whether such damage could lead to ROS production after PTP opening has occurred. Using isolated cardiac mitochondria, we demonstrate a novel mechanism by which antimycin-inhibited complex III generates significant amounts of ROS in the presence of Mg2+ and NAD+ and the absence of exogenous substrates upon inner membrane pore formation by alamethicin or Ca2+-induced PTP opening. We show that H2O2 production under these conditions is related to Mg2+-dependent NADH generation by malic enzyme. H2O2 production is blocked by stigmatellin, indicating its origin from complex III, and by piericidin, demonstrating the importance of NADH-related ubiquinone reduction for ROS production under these conditions. For maximal ROS production, the rate of NADH generation has to be equal or below that of NADH oxidation, as further increases in [NADH] elevate ubiquinol-related complex III reduction beyond the optimal range for ROS generation. These results suggest that if complex III is damaged during ischemia, PTP opening may result in succinate/malate-fueled ROS production from complex III due to activation of malic enzyme by increases in matrix [Mg2+], [NAD+], and [ADP].
Collapse
Affiliation(s)
- Paavo Korge
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Guillaume Calmettes
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Scott A John
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - James N Weiss
- From the UCLA Cardiovascular Research Laboratory and the Departments of Medicine (Cardiology) and Physiology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| |
Collapse
|
62
|
Chen Q, Lesnefsky EJ. A New Strategy to Treat Mitochondrial Disease Without Improvement of Mitochondrial Function? EBioMedicine 2017; 18:19-20. [PMID: 28330810 PMCID: PMC5405155 DOI: 10.1016/j.ebiom.2017.03.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Affiliation(s)
- Qun Chen
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States
| | - Edward J Lesnefsky
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, United States; McGuire VA Medical Center, Richmond, VA 23249, United States.
| |
Collapse
|
63
|
Hendgen-Cotta UB, Messiha D, Esfeld S, Deenen R, Rassaf T, Totzeck M. Inorganic nitrite modulates miRNA signatures in acute myocardial in vivo ischemia/reperfusion. Free Radic Res 2017; 51:91-102. [PMID: 28090786 DOI: 10.1080/10715762.2017.1282158] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Acute myocardial infarction is the leading cause of mortality in the industrialized world. While it is essential to attempt an early reperfusion of ischemic myocardial territories, reperfusion itself adds damage to the heart, the ischemia-reperfusion (I/R) injury. Particularly the injury resulting from the very first minutes of reperfusion remains incompletely understood. MicroRNAs (miRNAs) are dynamic regulators in I/R injury. Nitric oxide (•NO) signaling, in turn, interacts with miRNA signaling. Our previous investigations showed that •NO signaling in I/R could be modulated by nitrite. We therefore sought to investigate the role of miRNAs in nitrite cardioprotection with focus on the first few minutes of reperfusion. The study was conducted in mice in vivo with 30 min of ischemia and 5 min of reperfusion. Mice received a single-dose of nitrite or saline intracardially 5 min prior to reperfusion. We identified nine miRNAs to be up-regulated after 5 min of reperfusion. The up-regulation of almost half of those miRNAs (miR-125a-5p, miR-146b, miR-339-3p, miR-433) was inhibited by nitrite treatment, perpetuating baseline values. In silico analysis revealed the Irak-M gene to be a target of miR-146b and miR-339-3p. Correspondingly, a rise in Irak-M transcript and protein levels occurred by nitrite treatment within the early phase of reperfusion. The results demonstrate that already a very short phase of reperfusion is sufficient for significant dysregulation in cardiac miRNAs expression and that nitrite preserves baseline values of miRNAs in the scale of only a few minutes. These findings hint at a potential novel cardioprotective mechanism of nitrite signaling.
Collapse
Affiliation(s)
- Ulrike B Hendgen-Cotta
- a Department of Cardiology and Angiology, Medical Faculty , West German Heart and Vascular Center Essen, University Hospital Essen , Essen , Germany
| | - Daniel Messiha
- a Department of Cardiology and Angiology, Medical Faculty , West German Heart and Vascular Center Essen, University Hospital Essen , Essen , Germany
| | - Sonja Esfeld
- a Department of Cardiology and Angiology, Medical Faculty , West German Heart and Vascular Center Essen, University Hospital Essen , Essen , Germany
| | - René Deenen
- b Biological and Medical Research Center (BMFZ), Heinrich-Heine-University , Düsseldorf , Germany
| | - Tienush Rassaf
- a Department of Cardiology and Angiology, Medical Faculty , West German Heart and Vascular Center Essen, University Hospital Essen , Essen , Germany
| | - Matthias Totzeck
- a Department of Cardiology and Angiology, Medical Faculty , West German Heart and Vascular Center Essen, University Hospital Essen , Essen , Germany
| |
Collapse
|
64
|
Jespersen NR, Yokota T, Støttrup NB, Bergdahl A, Paelestik KB, Povlsen JA, Dela F, Bøtker HE. Pre-ischaemic mitochondrial substrate constraint by inhibition of malate-aspartate shuttle preserves mitochondrial function after ischaemia-reperfusion. J Physiol 2017; 595:3765-3780. [PMID: 28093764 DOI: 10.1113/jp273408] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 01/12/2017] [Indexed: 01/26/2023] Open
Abstract
KEY POINTS Pre-ischaemic administration of aminooxiacetate (AOA), an inhibitor of the malate-aspartate shuttle (MAS), provides cardioprotection against ischaemia-reperfusion injury. The underlying mechanism remains unknown. We examined whether transient inhibition of the MAS during ischaemia and early reperfusion by AOA treatment could prevent mitochondrial damage at later reperfusion. The AOA treatment preserved mitochondrial respiratory capacity with reduced mitochondrial oxidative stress during late reperfusion to the same extent as ischaemic preconditioning (IPC). However, AOA treatment, but not IPC, reduced the myocardial interstitial concentration of tricarboxylic acid cycle intermediates at the onset of reperfusion. The results obtained in the present study demonstrate that metabolic regulation by inhibition of the MAS at the onset of reperfusion may be beneficial for the preservation of mitochondrial function during late reperfusion in an IR-injured heart. ABSTRACT Mitochondrial dysfunction plays a central role in ischaemia-reperfusion (IR) injury. Pre-ischaemic administration of aminooxyacetate (AOA), an inhibitor of the malate-aspartate shuttle (MAS), provides cardioprotection against IR injury, although the underlying mechanism remains unknown. We hypothesized that a transient inhibition of the MAS during ischaemia and early reperfusion could preserve mitochondrial function at later phase of reperfusion in the IR-injured heart to the same extent as ischaemic preconditioning (IPC), which is a well-validated cardioprotective strategy against IR injury. In the present study, we show that pre-ischaemic administration of AOA preserved mitochondrial complex I-linked state 3 respiration and fatty acid oxidation during late reperfusion in IR-injured isolated rat hearts. AOA treatment also attenuated the excessive emission of mitochondrial reactive oxygen species during state 3 with complex I-linked substrates during late reperfusion, which was consistent with reduced oxidative damage in the IR-injured heart. As a result, AOA treatment reduced infarct size after reperfusion. These protective effects of MAS inhibition on the mitochondria were similar to those of IPC. Intriguingly, the protection of mitochondrial function by AOA treatment appears to be different from that of IPC because AOA treatment, but not IPC, downregulated myocardial tricarboxilic acid (TCA)-cycle intermediates at the onset of reperfusion. MAS inhibition thus preserved mitochondrial respiratory capacity and decreased mitochondrial oxidative stress during late reperfusion in the IR-injured heart, at least in part, via metabolic regulation of TCA cycle intermediates in the mitochondria at the onset of reperfusion.
Collapse
Affiliation(s)
| | - Takashi Yokota
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Andreas Bergdahl
- Department of Exercise Science, Concordia University, Montreal, Canada
| | | | | | - Flemming Dela
- Xlab, Center for Healthy Aging, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Geriatrics, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| |
Collapse
|
65
|
Lesnefsky EJ, Chen Q, Tandler B, Hoppel CL. Mitochondrial Dysfunction and Myocardial Ischemia-Reperfusion: Implications for Novel Therapies. Annu Rev Pharmacol Toxicol 2017; 57:535-565. [PMID: 27860548 PMCID: PMC11060135 DOI: 10.1146/annurev-pharmtox-010715-103335] [Citation(s) in RCA: 274] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mitochondria have emerged as key participants in and regulators of myocardial injury during ischemia and reperfusion. This review examines the sites of damage to cardiac mitochondria during ischemia and focuses on the impact of these defects. The concept that mitochondrial damage during ischemia leads to cardiac injury during reperfusion is addressed. The mechanisms that translate ischemic mitochondrial injury into cellular damage, during both ischemia and early reperfusion, are examined. Next, we discuss strategies that modulate and counteract these mechanisms of mitochondrial-driven injury. The new concept that mitochondria are not merely stochastic sites of oxidative and calcium-mediated injury but that they activate cellular responses of mitochondrial remodeling and cellular reactions that modulate the balance between cell death and recovery is reviewed, and the therapeutic implications of this concept are discussed.
Collapse
Affiliation(s)
- Edward J Lesnefsky
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia 23298; ,
- Medical Service, McGuire Veterans Affairs Medical Center, Richmond, Virginia 23249;
| | - Qun Chen
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia 23298; ,
| | - Bernard Tandler
- Department of Biological Sciences, Case Western Reserve University School of Dental Medicine, Cleveland, Ohio 44106;
| | - Charles L Hoppel
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106;
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
- Center for Mitochondrial Disease, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| |
Collapse
|
66
|
Mitochondrial Dysfunction in Cardiovascular Aging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 982:451-464. [PMID: 28551802 DOI: 10.1007/978-3-319-55330-6_24] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mitochondria are the prime source of ATP in cardiomyocytes. Impairment of mitochondrial metabolism results in damage to existing proteins and DNA. Such deleterious effects are part and parcel of the aging process, reducing the ability of cardiomyocytes to counter stress, such as myocardial infarction and consequent reperfusion. In such conditions, mitochondria in the heart of aged individuals exhibit decreased oxidative phosphorylation, decreased ATP production, and increased net reactive oxygen species production; all of these effects are independent of the decrease in number of mitochondria that occurs in these situations. Rather than being associated with the mitochondrial population in toto, these defects are almost exclusively confined to those organelles positioned between myofibrils (interfibrillar mitochondria). It is in complex III and IV where these dysfunctional aspects are manifested. In an apparent effort to correct mitochondrial metabolic defects, affected organelles are to some extent eliminated by mitophagy; at the same time, new, unaffected organelles are generated by fission of mitochondria. Because these cardiac health issues are localized to specific mitochondria, these organelles offer potential targets for therapeutic approaches that could favorably affect the aging process in heart.
Collapse
|
67
|
D'Alessandro A, Nemkov T, Bogren LK, Martin SL, Hansen KC. Comfortably Numb and Back: Plasma Metabolomics Reveals Biochemical Adaptations in the Hibernating 13-Lined Ground Squirrel. J Proteome Res 2016; 16:958-969. [PMID: 27991798 DOI: 10.1021/acs.jproteome.6b00884] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Hibernation is an evolutionary adaptation that affords some mammals the ability to exploit the cold to achieve extreme metabolic depression (torpor) while avoiding ischemia/reperfusion or hemorrhagic shock injuries. Hibernators cycle periodically out of torpor, restoring high metabolic activity. If understood at the molecular level, the adaptations underlying torpor-arousal cycles may be leveraged for translational applications in critical fields such as intensive care medicine. Here, we monitored 266 metabolites to investigate the metabolic adaptations to hibernation in plasma from 13-lined ground squirrels (57 animals, 9 time points). Results indicate that the periodic arousals foster the removal of potentially toxic oxidative stress-related metabolites, which accumulate in plasma during torpor while replenishing reservoirs of circulating catabolic substrates (free fatty acids and amino acids). Specifically, we identified metabolic fluctuations of basic amino acids lysine and arginine, one-carbon metabolism intermediates, and sulfur-containing metabolites methionine, cysteine, and cystathionine. Conversely, reperfusion injury markers such as succinate/fumarate remained relatively stable across cycles. Considering the cycles of these metabolites with the hibernator's cycling metabolic activity together with their well-established role as substrates for the production of hydrogen sulfide (H2S), we hypothesize that these metabolic fluctuations function as a biological clock regulating torpor to arousal transitions and resistance to reperfusion during arousal.
Collapse
Affiliation(s)
- Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics and ‡Department of Cell and Developmental Biology, University of Colorado Denver - Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Travis Nemkov
- Department of Biochemistry and Molecular Genetics and ‡Department of Cell and Developmental Biology, University of Colorado Denver - Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Lori K Bogren
- Department of Biochemistry and Molecular Genetics and ‡Department of Cell and Developmental Biology, University of Colorado Denver - Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Sandra L Martin
- Department of Biochemistry and Molecular Genetics and ‡Department of Cell and Developmental Biology, University of Colorado Denver - Anschutz Medical Campus , Aurora, Colorado 80045, United States
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics and ‡Department of Cell and Developmental Biology, University of Colorado Denver - Anschutz Medical Campus , Aurora, Colorado 80045, United States
| |
Collapse
|
68
|
Dong W, Zhou M, Dong M, Pan B, Liu Y, Shao J, Gu X, Huang Y, Li G, Wang Y, Sun H. Keto acid metabolites of branched-chain amino acids inhibit oxidative stress-induced necrosis and attenuate myocardial ischemia-reperfusion injury. J Mol Cell Cardiol 2016; 101:90-98. [PMID: 27832938 DOI: 10.1016/j.yjmcc.2016.11.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 11/01/2016] [Accepted: 11/03/2016] [Indexed: 01/06/2023]
Abstract
Branched chain α-keto acids (BCKAs) are endogenous metabolites of branched-chain amino acids (BCAAs). BCAA and BCKA are significantly elevated in pathologically stressed heart and contribute to chronic pathological remodeling and dysfunction. However, their direct impact on acute cardiac injury is unknown. Here, we demonstrated that elevated BCKAs significantly attenuated ischemia-reperfusion (I/R) injury and preserved post I/R function in isolated mouse hearts. BCKAs protected cardiomyocytes from oxidative stress-induced cell death in vitro. Mechanistically, BCKA protected oxidative stress induced cell death by inhibiting necrosis without affecting apoptosis or autophagy. Furthermore, BCKAs, but not BCAAs, protected mitochondria and energy production from oxidative injury. Finally, administration of BCKAs during reperfusion was sufficient to significantly attenuate cardiac I/R injury. These findings uncover an unexpected role of BCAA metabolites in cardioprotection against acute ischemia/reperfusion injury, and demonstrate the potential use of BCKA treatment to preserve ischemic tissue during reperfusion.
Collapse
Affiliation(s)
- Weibing Dong
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Meiyi Zhou
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Mei Dong
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Bangfen Pan
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Yunxia Liu
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jing Shao
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Xiaoping Gu
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Ying Huang
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Guangping Li
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin 300211, China
| | - Yibin Wang
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Division of Molecular Medicine, Departments of Anesthesiology, Medicine and Physiology, Molecular Biology Institute, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California, Los Angeles, CA 90095, USA
| | - Haipeng Sun
- Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.,Division of Molecular Medicine, Departments of Anesthesiology, Medicine and Physiology, Molecular Biology Institute, Cardiovascular Research Laboratories, David Geffen School of Medicine at University of California, Los Angeles, CA 90095, USA
| |
Collapse
|
69
|
Mitochondrial STAT3: Powering up a potent factor. Cytokine 2016; 87:20-5. [DOI: 10.1016/j.cyto.2016.05.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Accepted: 05/21/2016] [Indexed: 11/21/2022]
|
70
|
Keenaghan M, Sun L, Wang A, Hyodo E, Homma S, Ten VS. Intrauterine growth restriction impairs right ventricular response to hypoxia in adult male rats. Pediatr Res 2016; 80:547-53. [PMID: 27557421 DOI: 10.1038/pr.2016.124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 04/23/2016] [Indexed: 11/09/2022]
Abstract
BACKGROUND Intrauterine growth restriction (IUGR) predisposes to cardiovascular diseases in adulthood. The mechanisms of this phenomenon remain cryptic. We hypothesized that heart mitochondria in IUGR-born adult rats are more sensitive to acute hypoxia which translates into dysfunctional cardiac response to hypoxic stress. METHODS Adult IUGR-born male rats (the offspring of dams fed with calories-restricted diet during pregnancy) were exposed to acute hypoxic stress with echocardiographic assessment of cardiac function. In parallel, mitochondrial respiration in organelles isolated from left ventricle (LV) and right ventricle (RV) was tested in normoxic and anoxic conditions. The extent of post-anoxic inhibition of mitochondrial respiration and cardiac function was compared with controls, non-IUGR rats. RESULTS Compared with controls, in the IUGR rats hypoxia significantly reduced only RV contractility, evidenced by decreased fractional shortening, functional area of contraction, and tricuspid annular plane systolic excursion. In isolated mitochondria, anoxic challenge inhibited respiratory chain in both groups of rats. However, compared with controls, the extent of anoxic mitochondrial depression was significantly greater in IUGR-born rats, but only in the organelles isolated from RV. CONCLUSIONS In adult IUGR-born rats, mitochondria from RV are hypersensitive to oxygen deprivation and this translates into maladaptive RV cardiac response to acute hypoxia.
Collapse
Affiliation(s)
- Michael Keenaghan
- Department of Pediatrics, Kings County Hospital Center, Brooklyn, New York.,Department of Pediatrics, St. Georges University, Grenada, West Indies
| | - Lena Sun
- Department of Anesthesiology, Columbia University, New York, New York.,Department of Pediatrics, Columbia University, New York, New York
| | - Aili Wang
- Department of Anesthesiology, Columbia University, New York, New York
| | - Eiichi Hyodo
- Department of Medicine, Columbia University, New York, New York
| | - Sinichi Homma
- Department of Medicine, Columbia University, New York, New York
| | - Vadim S Ten
- Department of Pediatrics, Columbia University, New York, New York
| |
Collapse
|
71
|
Sureda A, Batle JM, Martorell M, Capó X, Tejada S, Tur JA, Pons A. Antioxidant Response of Chronic Wounds to Hyperbaric Oxygen Therapy. PLoS One 2016; 11:e0163371. [PMID: 27654305 PMCID: PMC5031445 DOI: 10.1371/journal.pone.0163371] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 09/06/2016] [Indexed: 01/24/2023] Open
Abstract
We analyzed the effects of the clinical hyperbaric oxygen therapy (HBOT) on the plasma antioxidant response and levels of endothelin-1, Interleukine-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with chronic wounds (20.2±10.0 months without healing). They received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20 before and 2 hours after the HBOT. An additional blood sample was collected 1 month after wound recovery. Serum creatine kinase activity decreased progressively in accordance with the wound healing. Plasma catalase activity significantly increased after the first and fifth sessions of HBOT. Plasma myeloperoxidase activity reported significantly lower values after sessions. Plasma VEGF and IL-6 increased after sessions. Endothelin-1 levels were progressively decreasing during the HBOT, being significant at the session 20. Plasma malondialdehyde concentration was significantly reduced at the last session. Both creatine kinase activity and malondialdehyde levels were maintained lower 1 month after wound recovery respect to initial values. In conclusion, HBOT enhanced the plasma antioxidant defenses and may contribute to activate the healing resolution, angiogenesis and vascular tone regulation by increasing the VEGF and IL-6 release and the endothelin-1 decrease, which may be significant factors in stimulating wound healing.
Collapse
Affiliation(s)
- Antoni Sureda
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
| | - Juan M. Batle
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
| | - Miquel Martorell
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
- Departamento de Nutrición y Dietética, Facultad de Farmacia, Universidad de Concepción, E-4070386, Concepción, Chile
| | - Xavier Capó
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
| | - Silvia Tejada
- Experimental Laboratory, Research Unit, Son Llàtzer Hospital, IUNICS, Ctra. Manacor km 4, E-07198, Palma de Mallorca, Balearic Islands, Spain
| | - Josep A. Tur
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
| | - Antoni Pons
- Research Group on Community Nutrition and Oxidative Stress, University of Balearic Islands, and CIBEROBN (Physiopathology of Obesity and Nutrition), E-07122, Palma de Mallorca, Balearic Islands, Spain
- * E-mail:
| |
Collapse
|
72
|
Pell VR, Chouchani ET, Frezza C, Murphy MP, Krieg T. Succinate metabolism: a new therapeutic target for myocardial reperfusion injury. Cardiovasc Res 2016; 111:134-41. [PMID: 27194563 DOI: 10.1093/cvr/cvw100] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 04/14/2016] [Indexed: 12/28/2022] Open
Abstract
Myocardial ischaemia/reperfusion (IR) injury is a major cause of death worldwide and remains a disease for which current clinical therapies are strikingly deficient. While the production of mitochondrial reactive oxygen species (ROS) is a critical driver of tissue damage upon reperfusion, the precise mechanisms underlying ROS production have remained elusive. More recently, it has been demonstrated that a specific metabolic mechanism occurs during ischaemia that underlies elevated ROS at reperfusion, suggesting a unifying model as to why so many different compounds have been found to be cardioprotective against IR injury. This review will discuss the role of the citric acid cycle intermediate succinate in IR pathology focusing on the mechanism by which this metabolite accumulates during ischaemia and how it can drive ROS production at Complex I via reverse electron transport. We will then examine the potential for manipulating succinate accumulation and metabolism during IR injury in order to protect the heart against IR damage and discuss targets for novel therapeutics designed to reduce reperfusion injury in patients.
Collapse
Affiliation(s)
- Victoria R Pell
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| | - Edward T Chouchani
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA Department of Cell Biology, Harvard Medical School, Boston, MA, USA
| | - Christian Frezza
- MRC Cancer Unit, University of Cambridge, Hutchison/MRC Research Centre, Box 197, Cambridge Biomedical Campus, Cambridge CB2 0XZ, UK
| | - Michael P Murphy
- MRC Mitochondrial Biology Unit, Hills Road, Cambridge CB2 0XY, UK
| | - Thomas Krieg
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
| |
Collapse
|
73
|
Abstract
Ischemia-reperfusion (IR) injury occurs when blood supply to an organ is disrupted--ischemia--and then restored--reperfusion--leading to a burst of reactive oxygen species (ROS) from mitochondria. It has been tacitly assumed that ROS production during IR is a non-specific consequence of oxygen interacting with dysfunctional mitochondria upon reperfusion. Recently, this view has changed, suggesting that ROS production during IR occurs by a defined mechanism. Here we survey the metabolic factors underlying IR injury and propose a unifying mechanism for its causes that makes sense of the huge amount of disparate data in this area and provides testable hypotheses and new directions for therapies.
Collapse
|
74
|
Thompson J, Hu Y, Lesnefsky EJ, Chen Q. Activation of mitochondrial calpain and increased cardiac injury: beyond AIF release. Am J Physiol Heart Circ Physiol 2016; 310:H376-84. [PMID: 26637561 PMCID: PMC4796621 DOI: 10.1152/ajpheart.00748.2015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/23/2015] [Indexed: 12/14/2022]
Abstract
Calpain 1 (CPN1) is a ubiquitous cysteine protease that exists in both cytosol and cardiac mitochondria. Mitochondrial CPN1 (mit-CPN1) is located in the intermembrane space and matrix. Activation of mit-CPN1 within the intermembrane space increases cardiac injury by releasing apoptosis-inducing factor from mitochondria during ischemia-reperfusion (IR). We asked if activation of mit-CPN1 is involved in mitochondrial injury during IR. MDL-28170 (MDL) was used to inhibit CPN1 in buffer-perfused hearts following 25-min ischemia and 30-min reperfusion. MDL treatment decreased the release of lactate dehydrogenase into coronary effluent compared with untreated hearts, indicating that inhibition of CPN1 decreases cardiac injury. MDL also prevented the cleavage of spectrin (a substrate of CPN1) in cytosol during IR, supporting that MDL treatment decreased cytosolic calpain activation. In addition, MDL markedly improved calcium retention capacity compared with untreated heart, suggesting that MDL treatment decreases mitochondrial permeability transition pore opening. In addition, we found that IR led to decreased complex I activity, whereas inhibition of mit-CPN1 using MDL protected complex I. Pyruvate dehydrogenase content was decreased following IR. However, pyruvate dehydrogenase content was preserved in MDL-treated mitochondria. Taken together, MDL treatment decreased cardiac injury during IR by inhibiting both cytosolic and mit-CPN1. Activation of mit-CPN1 increases cardiac injury during IR by sensitizing mitochondrial permeability transition pore opening and impairing mitochondrial metabolism through damage of complex I.
Collapse
Affiliation(s)
- Jeremy Thompson
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - Ying Hu
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - Edward J Lesnefsky
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University, Richmond, Virginia; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia; Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, Virginia; and McGuire Veterans Affairs Medical Center, Richmond, Virginia
| | - Qun Chen
- Division of Cardiology, Department of Medicine, Virginia Commonwealth University, Richmond, Virginia;
| |
Collapse
|
75
|
Acquired deficiency of tafazzin in the adult heart: Impact on mitochondrial function and response to cardiac injury. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1861:294-300. [PMID: 26692032 DOI: 10.1016/j.bbalip.2015.12.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/11/2015] [Accepted: 12/11/2015] [Indexed: 12/22/2022]
Abstract
The content and composition of cardiolipin (CL) is critical for preservation of mitochondrial oxidative phosphorylation (OXPHOS) and inner membrane integrity. Tafazzin (Taz) is an enzyme responsible for remodeling of immature CL containing mixed acyl groups into the mature tetralinoleyl form (C18:2)4-CL. We hypothesized that acquired defects in Taz in the mature heart would impact remodeling of CL and augment cardiac injury. The role of acquired Taz deficiency was studied using the inducible Taz knockdown (TazKD) mouse. Taz-specific shRNA is induced by doxycycline (DOX). One day of DOX intake decreased Taz mRNA in the heart to 20% vs. DOX-treated WT. Knockdown was initiated at an adult age and was stable during long term feeding. CL phenotype was assessed by (C18:2)4-CL content and was reduced 40% vs. WT at two months of DOX. TazKD showed increased production of reactive oxygen species and increased susceptibility to permeability transition pore opening at baseline. However, OXPHOS measured using the rate of oxygen consumption was unchanged in the setting of acquired Taz deficiency. Infarct size, measured in isolated buffer-perfused Langendorff hearts following 25min. Stop flow ischemia and 60min. Reperfusion was not altered in TazKD hearts. Thus, impaired Taz-function with onset at adult age does not enhance susceptibility to ischemia-reperfusion injury.
Collapse
|
76
|
Szczepanek K, Xu A, Hu Y, Thompson J, He J, Larner AC, Salloum FN, Chen Q, Lesnefsky EJ. Cardioprotective function of mitochondrial-targeted and transcriptionally inactive STAT3 against ischemia and reperfusion injury. Basic Res Cardiol 2015; 110:53. [DOI: 10.1007/s00395-015-0509-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 08/19/2015] [Indexed: 01/20/2023]
|
77
|
Chen Q, Lesnefsky EJ. Heart mitochondria and calpain 1: Location, function, and targets. Biochim Biophys Acta Mol Basis Dis 2015; 1852:2372-8. [PMID: 26259540 DOI: 10.1016/j.bbadis.2015.08.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/17/2015] [Accepted: 08/06/2015] [Indexed: 12/22/2022]
Abstract
Calpain 1 is an ubiquitous Ca(2+)-dependent cysteine protease. Although calpain 1 has been found in cardiac mitochondria, the exact location within mitochondrial compartments and its function remain unclear. The aim of the current review is to discuss the localization of calpain 1 in different mitochondrial compartments in relationship to its function, especially in pathophysiological conditions. Briefly, mitochondrial calpain 1 (mit-CPN1) is located within the intermembrane space and mitochondrial matrix. Activation of the mit-CPN1 within intermembrane space cleaves apoptosis inducing factor (AIF), whereas the activated mit-CPN1 within matrix cleaves complex I subunits and metabolic enzymes. Inhibition of the mit-CPN1 could be a potential strategy to decrease cardiac injury during ischemia-reperfusion.
Collapse
Affiliation(s)
- Qun Chen
- Department of Medicine (Division of Cardiology, Pauley Heart Center), Virginia Commonwealth University, Richmond, VA 23298, United States.
| | - Edward J Lesnefsky
- Department of Medicine (Division of Cardiology, Pauley Heart Center), Virginia Commonwealth University, Richmond, VA 23298, United States; Department of Biochemistry, Virginia Commonwealth University, Richmond, VA 23298, United States; Department of Physiology, Virginia Commonwealth University, Richmond, VA 23298, United States; McGuire VA Medical Center, Richmond, VA 23249, United States
| |
Collapse
|
78
|
de Lima Portella R, Lynn Bickta J, Shiva S. Nitrite Confers Preconditioning and Cytoprotection After Ischemia/Reperfusion Injury Through the Modulation of Mitochondrial Function. Antioxid Redox Signal 2015; 23:307-27. [PMID: 26094636 DOI: 10.1089/ars.2015.6260] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
SIGNIFICANCE Nitrite is now recognized as an intrinsic signaling molecule that mediates a number of biological processes. One of the most reproducible effects of nitrite is its ability to mediate cytoprotection after ischemia/reperfusion (I/R). This robust phenomenon has been reproduced by a number of investigators in varying animal models focusing on different target organs. Furthermore, nitrite's cytoprotective versatility is highlighted by its ability to mediate delayed preconditioning and remote conditioning in addition to acute protection. RECENT ADVANCES In the last 10 years, significant progress has been made in elucidating the mechanisms underlying nitrite-mediated ischemic tolerance. CRITICAL ISSUES The mitochondrion, which is essential to both the progression of I/R injury and the protection afforded by preconditioning, has emerged as a major subcellular target for nitrite. This review will outline the role of the mitochondrion in I/R injury and preconditioning, review the accumulated preclinical studies demonstrating nitrite-mediated cytoprotection, and finally focus on the known interactions of nitrite with mitochondria and their role in the mechanism of nitrite-mediated ischemic tolerance. FUTURE DIRECTIONS These studies set the stage for current clinical trials testing the efficacy of nitrite to prevent warm and cold I/R injury.
Collapse
Affiliation(s)
- Rafael de Lima Portella
- 1 Vascular Medicine Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Janelle Lynn Bickta
- 1 Vascular Medicine Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania.,2 Department of Bioengineering, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Sruti Shiva
- 1 Vascular Medicine Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania.,3 Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania.,4 Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| |
Collapse
|
79
|
Chen Q, Xu H, Xu A, Ross T, Bowler E, Hu Y, Lesnefsky EJ. Inhibition of Bcl-2 sensitizes mitochondrial permeability transition pore (MPTP) opening in ischemia-damaged mitochondria. PLoS One 2015; 10:e0118834. [PMID: 25756500 PMCID: PMC4354902 DOI: 10.1371/journal.pone.0118834] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 01/15/2015] [Indexed: 11/21/2022] Open
Abstract
Background Mitochondria are critical to cardiac injury during reperfusion as a result of damage sustained during ischemia, including the loss of bcl-2. We asked if bcl-2 depletion not only leads to selective permeation of the outer mitochondrial membrane (MOMP) favoring cytochrome c release and programmed cell death, but also favors opening of the mitochondrial permeability transition pore (MPTP). An increase in MPTP susceptibility would support a role for bcl-2 depletion mediated cell death in the calcium overload setting of early reperfusion via MPTP as well as later in reperfusion via MOMP as myocardial calcium content normalizes. Methods Calcium retention capacity (CRC) was used to reflect the sensitivity of the MPTP opening in isolated cardiac mitochondria. To study the relationship between bcl-2 inhibition and MPTP opening, mitochondria were incubated with a bcl-2 inhibitor (HA14-1) and CRC measured. The contribution of preserved bcl-2 content to MPTP opening following ischemia-reperfusion was explored using transgenic bcl-2 overexpressed mice. Results CRC was decreased in mitochondria following reperfusion compared to ischemia alone, indicating that reperfusion further sensitizes to MPTP opening. Incubation of ischemia-damaged mitochondria with increasing HA14-1concentrations increased calcium-stimulated MPTP opening, supporting that functional inhibition of bcl-2 during simulated reperfusion favors MPTP opening. Moreover, HA14-1 sensitivity was increased by ischemia compared to non-ischemic controls. Overexpression of bcl-2 attenuated MPTP opening in following ischemia-reperfusion. HA14-1 inhibition also increased the permeability of the outer membrane in the absence of exogenous calcium, indicating that bcl-2 inhibition favors MOMP when calcium is low. Conclusions The depletion and functional inhibition of bcl-2 contributes to cardiac injury by increasing susceptibility to MPTP opening in high calcium environments and MOMP in the absence of calcium overload. Thus, ischemia-damaged mitochondria with decreased bcl-2 content are susceptible to MPTP opening in early reperfusion and MOMP later in reperfusion when cytosolic calcium has normalized.
Collapse
Affiliation(s)
- Qun Chen
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Haishan Xu
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Aijun Xu
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
- Department of Anesthesiology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Thomas Ross
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Elizabeth Bowler
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
- University of the West of England, Bristol, United Kingdom
| | - Ying Hu
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
| | - Edward J. Lesnefsky
- Department of Medicine, Pauley Heart Center, Division of Cardiology, Virginia Commonwealth University, Richmond, Virginia, United States of America
- Department of Medicine, Pauley Heart Center, Division of Biochemistry, Virginia Commonwealth University, Richmond, Virginia, United States of America
- McGuire Department of Veterans Affairs Medical Center, Richmond, Virginia, United States of America
- * E-mail:
| |
Collapse
|
80
|
Kikuchi C, Dosenovic S, Bienengraeber M. Anaesthetics as cardioprotectants: translatability and mechanism. Br J Pharmacol 2015; 172:2051-61. [PMID: 25322898 DOI: 10.1111/bph.12981] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/06/2014] [Accepted: 10/11/2014] [Indexed: 12/22/2022] Open
Abstract
The pharmacological conditioning of the heart with anaesthetics, such as volatile anaesthetics or opioids, is a phenomenon whereby a transient exposure to an anaesthetic agent protects the heart from the harmful consequences of myocardial ischaemia and reperfusion injury. The cellular and molecular mechanisms of anaesthetic conditioning appear largely to mimic those of ischaemic pre- and post-conditioning. Progress has been made on the understanding of the underlying mechanisms although the order of events and the specific targets of anaesthetics that trigger protection are not always clear. In the laboratory, the protection afforded by certain anaesthetics against cardiac ischaemia and reperfusion injury is powerful and reproducible but this has not necessarily translated into similarly robust clinical benefits. Indeed, clinical studies and meta-analyses delivered variable results when comparing in the laboratory setting protective and non-protective anaesthetics. Reasons for this include underlying conditions such as age, obesity and diabetes. Animal models for disease or ageing, human cardiomyocytes derived from stem cells of patients and further clinical studies are employed to better understand the underlying causes that prevent a more robust protection in patients.
Collapse
Affiliation(s)
- C Kikuchi
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Anesthesiology, Asahikawa Medical University, Asahikawa, Japan
| | | | | |
Collapse
|
81
|
Kikuchi C, Dosenovic S, Bienengraeber M. Anaesthetics as cardioprotectants: translatability and mechanism. Br J Pharmacol 2015. [PMID: 25322898 DOI: 10.1111/bph.2015.172.issue-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The pharmacological conditioning of the heart with anaesthetics, such as volatile anaesthetics or opioids, is a phenomenon whereby a transient exposure to an anaesthetic agent protects the heart from the harmful consequences of myocardial ischaemia and reperfusion injury. The cellular and molecular mechanisms of anaesthetic conditioning appear largely to mimic those of ischaemic pre- and post-conditioning. Progress has been made on the understanding of the underlying mechanisms although the order of events and the specific targets of anaesthetics that trigger protection are not always clear. In the laboratory, the protection afforded by certain anaesthetics against cardiac ischaemia and reperfusion injury is powerful and reproducible but this has not necessarily translated into similarly robust clinical benefits. Indeed, clinical studies and meta-analyses delivered variable results when comparing in the laboratory setting protective and non-protective anaesthetics. Reasons for this include underlying conditions such as age, obesity and diabetes. Animal models for disease or ageing, human cardiomyocytes derived from stem cells of patients and further clinical studies are employed to better understand the underlying causes that prevent a more robust protection in patients.
Collapse
Affiliation(s)
- C Kikuchi
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Anesthesiology, Asahikawa Medical University, Asahikawa, Japan
| | | | | |
Collapse
|
82
|
Yao L, Wang P, Chen M, Liu Y, Zhou L, Fang X, Huang Z. Carbon Monoxide-Releasing Molecules Attenuate Postresuscitation Myocardial Injury and Protect Cardiac Mitochondrial Function by Reducing the Production of Mitochondrial Reactive Oxygen Species in a Rat Model of Cardiac Arrest. J Cardiovasc Pharmacol Ther 2014; 20:330-41. [PMID: 25420477 DOI: 10.1177/1074248414559837] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 09/30/2014] [Indexed: 01/01/2023]
Abstract
The objective of this study is to examine whether carbon monoxide-releasing molecules (CORMs) can decrease the generation of excessive reactive oxygen species (ROS) in cardiac mitochondria, thereby protecting against postresuscitation myocardial injury and cardiac mitochondrial dysfunction after resuscitation in a rat model of ventricular fibrillation (VF), and further investigated the underlying mechanism. Rats suffered 8 minutes of untreated VF and resuscitation and were randomized into the control group with vehicle infusion and the CORM group with CO-releasing molecule 2 (CORM2) treatment. Animals in the Sham group were instrumented without induced VF and resuscitation. Effects of CORM2 on cardiac function, myocardial oxidative stress, cardiac mitochondrial function, and mitochondrial ROS generation were assessed. Moreover, to further evaluate the direct effect of CORM2 on cardiac mitochondria isolated from resuscitated rats, we measured mitochondrial function and ROS generation when isolated cardiac mitochondria were directly incubated with different concentrations of (CORM2). Compared with the Sham group, the control and CORM groups demonstrated impaired cardiac function, increased myocardial injury, and aggravated mitochondrial damage. CORM2 improved cardiac performance and attenuated myocardial damage and oxidative stress in resuscitated rats. Additionally, animals with CORM2 treatment showed the decreased generation of cardiac mitochondrial ROS, alleviated mitochondrial injury, and preserved mitochondrial function and complex activities when compared with the control group. In isolated cardiac mitochondria incubated with CORM2, low concentrations of CORM2 (20 μmol/L) mildly uncoupled mitochondrial respiration, leading to reduced mitochondrial ROS production. In contrast, high concentrations of CORM2 (60 μmol/L) resulted in the reverse effect presumably due to its excessive uncoupling action. These findings suggest that CORM2 attenuates oxidative stress of the heart and improves cardiac function after resuscitation. The mechanism was probably that CO, the product of CORM2, reduces the production of cardiac mitochondrial ROS and thereby attenuates mitochondrial injury and dysfunction during the postresuscitation period, due to the transient uncoupling of mitochondrial respiration.
Collapse
Affiliation(s)
- Lan Yao
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
- Department of Emergency Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
| | - Peng Wang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| | - Mingdi Chen
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| | - Yuanshan Liu
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| | - Lili Zhou
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| | - Xiangshao Fang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| | - Zitong Huang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
- Institute of Cardiopulmonary Cerebral Resuscitation, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
83
|
Baqri RM, Pietron AV, Gokhale RH, Turner BA, Kaguni LS, Shingleton AW, Kunes S, Miller KE. Mitochondrial chaperone TRAP1 activates the mitochondrial UPR and extends healthspan in Drosophila. Mech Ageing Dev 2014; 141-142:35-45. [PMID: 25265088 DOI: 10.1016/j.mad.2014.09.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 08/22/2014] [Accepted: 09/19/2014] [Indexed: 01/06/2023]
Abstract
The molecular mechanisms influencing healthspan are unclear but mitochondrial function, resistance to oxidative stress and proteostasis are recurring themes. Tumor necrosis factor Receptor Associated Protein 1 (TRAP1), the mitochondrial analog of Hsp75, regulates levels of reactive oxygen species in vitro and is found expressed at higher levels in tumor cells where it is thought to play a pro-survival role. While TRAP1-directed compartmentalized protein folding is a promising target for cancer therapy, its role at the organismal level is unclear. Here we report that overexpression of TRAP1 in Drosophila extends healthspan by enhancing stress resistance, locomotor activity and fertility while depletion of TRAP1 has the opposite effect, with little effect on lifespan under both conditions. In addition, modulating TRAP1 expression promotes the nuclear translocation of homeobox protein Dve and increases expression of genes associated with the mitochondrial unfolded protein response (UPR(mt)), indicating an activation of this proteostasis pathway. Notably, independent genetic knockdown of components of the UPR(mt) pathway dampen the enhanced stress resistance observed in TRAP1 overexpression flies. Together these studies suggest that TRAP1 regulates healthspan, potentially through activation of the UPR(mt).
Collapse
Affiliation(s)
- Rehan M Baqri
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA; Neuroscience Program, Michigan State University, 108 Giltner Hall, East Lansing, MI 48824-1115, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Arielle V Pietron
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA
| | - Rewatee H Gokhale
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA
| | - Brittany A Turner
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA; Department of Biochemistry and Molecular Biology, 319 Biochemistry Building, Michigan State University, East Lansing, MI 48824-1319, USA
| | - Laurie S Kaguni
- Department of Biochemistry and Molecular Biology, 319 Biochemistry Building, Michigan State University, East Lansing, MI 48824-1319, USA; Center for Mitochondrial Science and Medicine, Michigan State University, East Lansing, MI 48824-1319, USA
| | - Alexander W Shingleton
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA
| | - Sam Kunes
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Kyle E Miller
- Department of Zoology, Michigan State University, 203 Natural Sciences Building, East Lansing, MI 48824-1115, USA; Neuroscience Program, Michigan State University, 108 Giltner Hall, East Lansing, MI 48824-1115, USA; Center for Mitochondrial Science and Medicine, Michigan State University, East Lansing, MI 48824-1319, USA.
| |
Collapse
|
84
|
Hollander JM, Thapa D, Shepherd DL. Physiological and structural differences in spatially distinct subpopulations of cardiac mitochondria: influence of cardiac pathologies. Am J Physiol Heart Circ Physiol 2014; 307:H1-14. [PMID: 24778166 DOI: 10.1152/ajpheart.00747.2013] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Cardiac tissue contains discrete pools of mitochondria that are characterized by their subcellular spatial arrangement. Subsarcolemmal mitochondria (SSM) exist below the cell membrane, interfibrillar mitochondria (IFM) reside in rows between the myofibrils, and perinuclear mitochondria are situated at the nuclear poles. Microstructural imaging of heart tissue coupled with the development of differential isolation techniques designed to sequentially separate spatially distinct mitochondrial subpopulations have revealed differences in morphological features including shape, absolute size, and internal cristae arrangement. These findings have been complemented by functional studies indicating differences in biochemical parameters and, potentially, functional roles for the ATP generated, based upon subcellular location. Consequently, mitochondrial subpopulations appear to be influenced differently during cardiac pathologies including ischemia/reperfusion, heart failure, aging, exercise, and diabetes mellitus. These influences may be the result of specific structural and functional disparities between mitochondrial subpopulations such that the stress elicited by a given cardiac insult differentially impacts subcellular locales and the mitochondria contained within. The goal of this review is to highlight some of the inherent structural and functional differences that exist between spatially distinct cardiac mitochondrial subpopulations as well as provide an overview of the differential impact of various cardiac pathologies on spatially distinct mitochondrial subpopulations. As an outcome, we will instill a basis for incorporating subcellular spatial location when evaluating the impact of cardiac pathologies on the mitochondrion. Incorporation of subcellular spatial location may offer the greatest potential for delineating the influence of cardiac pathology on this critical organelle.
Collapse
|
85
|
Abstract
Hydrogen sulfide (H2S) is an endogenously produced gaseous signaling molecule that elicits a number of cytoprotective effects in mammalian species. H2S was originally considered toxic at elevated levels, but 15 years ago the labile molecule was discovered in mammalian tissue and termed a gasotransmitter, thus opening the door for research aimed towards understanding its physiologic nature. Since then, novel findings have depicted the beneficial aspects of H2S therapy, such as vasodilation, antioxidant upregulation, inflammation inhibition, and activation of anti-apoptotic pathways. These cytoprotective alterations effectively treat multiple forms of cardiac injury at the preclinical level of research. The field has progressed towards instituting novel H2S donors that prove more effective at activating the subsequent cardioprotective enhancements over longer time periods. As more findings explore the efficacy of H2S, research focused on detection of sulfhydrated targets is on the rise. Understanding the molecular mechanisms that stem from H2S treatment may lead the field towards powerful therapeutics in the clinical setting. This review will discuss the cytoprotective and cardioprotective effects of H2S therapy, provide analysis on the molecular alterations that lead to these enhancements, and explore recently developed therapeutics that may bring this gasotransmitter into the clinic in the near future.
Collapse
Affiliation(s)
- Larry A Barr
- Department of Surgery, Division of Cardiothoracic Surgery, Carlyle Fraser Heart Center, Emory University School of Medicine
| | | |
Collapse
|
86
|
Electron flow into cytochrome c coupled with reactive oxygen species from the electron transport chain converts cytochrome c to a cardiolipin peroxidase: role during ischemia-reperfusion. Biochim Biophys Acta Gen Subj 2014; 1840:3199-207. [PMID: 25092652 DOI: 10.1016/j.bbagen.2014.07.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 07/07/2014] [Accepted: 07/28/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Cytochrome c (Cyt c) is a mobile component of the electron transport chain (ETC.) which contains a tightly coordinated heme iron. In pathologic settings, a key ligand of the cyt c's heme iron, methionine (Met80), is oxidized allowing cyt c to participate in reactions as a peroxidase with cardiolipin as a target. Myocardial ischemia (ISC) results in ETC. blockade and increased production of reactive oxygen species (ROS). We hypothesized that during ischemia-reperfusion (ISC-REP); ROS generation coupled with electron flow into cyt c would oxidize Met80 and contribute to mitochondrial-mediated ETC. damage. METHODS Mitochondria were incubated with specific substrates and inhibitors to test the contributions of ROS and electron flow into cyt c. Subsequently, cyt c and cardiolipin were analyzed. To test the pathophysiologic relevance, mouse hearts that underwent ISC-REP were tested for methionine oxidation in cyt c. RESULTS The combination of substrate/inhibitor showed that ROS production and electron flux through cyt c are essential for the oxidation of methionine residues that lead to cardiolipin depletion. The content of cyt c methionine oxidation increases following ISC-REP in the intact heart. CONCLUSIONS Increase in intra-mitochondrial ROS coupled with electron flow into cyt c, oxidizes cyt c followed by depletion of cardiolipin. ISC-REP increases methionine oxidation, supporting that cyt c peroxidase activity can form in the intact heart. GENERAL SIGNIFICANCE This study identifies a new site in the ETC. that is damaged during cardiac ISC-REP. Generation of a neoperoxidase activity of cyt c favors the formation of a defective ETC. that activates signaling for cell death.
Collapse
|
87
|
Chen Q, Szczepanek K, Hu Y, Thompson J, Lesnefsky EJ. A deficiency of apoptosis inducing factor (AIF) in Harlequin mouse heart mitochondria paradoxically reduces ROS generation during ischemia-reperfusion. Front Physiol 2014; 5:271. [PMID: 25101006 PMCID: PMC4106194 DOI: 10.3389/fphys.2014.00271] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 06/30/2014] [Indexed: 12/30/2022] Open
Abstract
Background and Aims: AIF (apoptosis inducing factor) is a flavin and NADH containing protein located within mitochondria required for optimal function of the respiratory chain. AIF may function as an antioxidant within mitochondria, yet when released from mitochondria it activates caspase-independent cell death. The Harlequin (Hq) mouse has a markedly reduced content of AIF, providing an experimental model to query if the main role of AIF in the exacerbation of cell death is enhanced mitochondrial generation of reactive oxygen species (ROS) or the activation of cell death programs. We asked if the ROS generation is altered in Hq heart mitochondria at baseline or following ischemia-reperfusion (IR). Methods: Buffer perfused mouse hearts underwent 30 min ischemia and 30 min reperfusion. Mitochondrial function including oxidative phosphorylation and H2O2 generation was measured. Immunoblotting was used to determine the contents of AIF and PAR [poly(ADP-ribose)] in cell fractions. Results: There were no differences in the release of H2O2 between wild type (WT) and Hq heart mitochondria at baseline. IR increased H2O2 generation from WT but not from Hq mitochondria compared to corresponding time controls. The complex I activity was decreased in WT but not in Hq mice following IR. The relocation of AIF from mitochondria to nucleus was increased in WT but not in Hq mice. IR activated PARP-1 only in WT mice. Cell injury was decreased in the Hq mouse heart following in vitro IR. Conclusion: A deficiency of AIF within mitochondria does not increase ROS production during IR, indicating that AIF functions less as an antioxidant within mitochondria. The decreased cardiac injury in Hq mouse heart accompanied by less AIF translocation to the nucleus suggests that AIF relocation, rather than the AIF content within mitochondria, contributes to cardiac injury during IR.
Collapse
Affiliation(s)
- Qun Chen
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University Richmond, VA, USA
| | - Karol Szczepanek
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University Richmond, VA, USA
| | - Ying Hu
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University Richmond, VA, USA
| | - Jeremy Thompson
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University Richmond, VA, USA
| | - Edward J Lesnefsky
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University Richmond, VA, USA ; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University Richmond, VA, USA ; McGuire Department of Veterans Affairs Medical Center Richmond, VA, USA
| |
Collapse
|
88
|
Rozmer Z, Berki T, Maász G, Perjési P. Different effects of two cyclic chalcone analogues on redox status of Jurkat T cells. Toxicol In Vitro 2014; 28:1359-65. [PMID: 25014873 DOI: 10.1016/j.tiv.2014.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 05/12/2014] [Accepted: 06/23/2014] [Indexed: 10/25/2022]
Abstract
Chalcones are intermediary compounds of the biosynthetic pathway of the naturally flavonoids. Previous studies have demonstrated that chalcones and their conformationally rigid cyclic analogues have tumour cell cytotoxic and chemopreventive effects. It has been shown that equitoxic doses of the two cyclic chalcone analogues (E)-2-(4'-methoxybenzylidene)-(2) and (E)-2-(4'-methylbenzylidene)-1-benzosuberone (3) have different effect on cell cycle progress of the investigated Jurkat cells. It was also found that the compounds affect the cellular thiol status of the treated cells and show intrinsic (non-enzyme-catalyzed) reactivity towards GSH under cell-free conditions. In order to gain new insights into the cytotoxic mechanism of the compounds, effects on the redox status and glutathione level of Jurkat cells were investigated. Detection of intracellular ROS level in Jurkat cells exposed to 2 and 3 was performed using the dichlorofluorescein-assay. Compound 2 did not influence ROS activity either on 1 or 4h exposure; in contrast, chalcone 3 showed to reduce ROS level at both timepoints. The two compounds had different effects on cellular glutathione status as well. Compound 2 significantly increased the oxidized glutathione (GSSG) level showing an interference with the cellular antioxidant defence. On the contrary, chalcone 3 enhanced the reduced glutathione level, indicating enhanced cellular antioxidant activity. To investigate the chalcone-GSH conjugation reactions under cellular conditions, a combination of a RP-HPLC method with electrospray ionization mass spectrometry (ESI-MS) was performed. Chalcone-GSH adducts could not be observed either in the cell supernatant or the cell sediment after deproteinization. The investigations provide further details of dual - cytotoxic and chemopreventive - effects of the cyclic chalcone analogues.
Collapse
Affiliation(s)
- Zsuzsanna Rozmer
- Department of Pharmaceutical Chemistry, University of Pécs, P.O. Box 99, H-7602 Pécs, Hungary
| | - Tímea Berki
- Department of Immunology and Biotechnology, University of Pécs, P.O. Box 99, H-7602 Pécs, Hungary
| | - Gábor Maász
- Department of Biochemistry and Medical Chemistry, University of Pécs, P.O. Box 99, H-7602 Pécs, Hungary
| | - Pál Perjési
- Department of Pharmaceutical Chemistry, University of Pécs, P.O. Box 99, H-7602 Pécs, Hungary.
| |
Collapse
|
89
|
Polhemus DJ, Calvert JW, Butler J, Lefer DJ. The cardioprotective actions of hydrogen sulfide in acute myocardial infarction and heart failure. SCIENTIFICA 2014; 2014:768607. [PMID: 25045576 PMCID: PMC4090472 DOI: 10.1155/2014/768607] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 04/30/2014] [Accepted: 05/16/2014] [Indexed: 06/03/2023]
Abstract
It has now become universally accepted that hydrogen sulfide (H2S), previously considered only as a lethal toxin, has robust cytoprotective actions in multiple organ systems. The diverse signaling profile of H2S impacts multiple pathways to exert cytoprotective actions in a number of pathological states. This paper will review the recently described cardioprotective actions of hydrogen sulfide in both myocardial ischemia/reperfusion injury and congestive heart failure.
Collapse
Affiliation(s)
- David J. Polhemus
- Department of Pharmacology and Experimental Therapeutics and Cardiovascular Center of Excellence, LSU Health Sciences Center, New Orleans, LA 70112, USA
| | - John W. Calvert
- Department of Surgery, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Javed Butler
- Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - David J. Lefer
- Department of Pharmacology and Experimental Therapeutics and Cardiovascular Center of Excellence, LSU Health Sciences Center, New Orleans, LA 70112, USA
| |
Collapse
|
90
|
Kalogeris T, Bao Y, Korthuis RJ. Mitochondrial reactive oxygen species: a double edged sword in ischemia/reperfusion vs preconditioning. Redox Biol 2014; 2:702-14. [PMID: 24944913 PMCID: PMC4060303 DOI: 10.1016/j.redox.2014.05.006] [Citation(s) in RCA: 505] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 05/23/2014] [Accepted: 05/27/2014] [Indexed: 02/06/2023] Open
Abstract
Reductions in the blood supply produce considerable injury if the duration of ischemia is prolonged. Paradoxically, restoration of perfusion to ischemic organs can exacerbate tissue damage and extend the size of an evolving infarct. Being highly metabolic organs, the heart and brain are particularly vulnerable to the deleterious effects of ischemia/reperfusion (I/R). While the pathogenetic mechanisms contributing to I/R-induced tissue injury and infarction are multifactorial, the relative importance of each contributing factor remains unclear. However, an emerging body of evidence indicates that the generation of reactive oxygen species (ROS) by mitochondria plays a critical role in damaging cellular components and initiating cell death. In this review, we summarize our current understanding of the mechanisms whereby mitochondrial ROS generation occurs in I/R and contributes to myocardial infarction and stroke. In addition, mitochondrial ROS have been shown to participate in preconditioning by several pharmacologic agents that target potassium channels (e.g., ATP-sensitive potassium (mKATP) channels or large conductance, calcium-activated potassium (mBKCa) channels) to activate cell survival programs that render tissues and organs more resistant to the deleterious effects of I/R. Finally, we review novel therapeutic approaches that selectively target mROS production to reduce postischemic tissue injury, which may prove efficacious in limiting myocardial dysfunction and infarction and abrogating neurocognitive deficits and neuronal cell death in stroke.
Collapse
Affiliation(s)
- Theodore Kalogeris
- Department of Medical Pharmacology and Physiology, School of Medicine, Dalton Cardiovascular Research Center, University of Missouri, 1 Hospital Drive, Columbia, MO 65212-0001, United States of America
| | - Yimin Bao
- Department of Medical Pharmacology and Physiology, School of Medicine, Dalton Cardiovascular Research Center, University of Missouri, 1 Hospital Drive, Columbia, MO 65212-0001, United States of America
| | - Ronald J Korthuis
- Department of Medical Pharmacology and Physiology, School of Medicine, Dalton Cardiovascular Research Center, University of Missouri, 1 Hospital Drive, Columbia, MO 65212-0001, United States of America
| |
Collapse
|
91
|
Molecular mechanism and physiological role of active-deactive transition of mitochondrial complex I. Biochem Soc Trans 2014; 41:1325-30. [PMID: 24059527 PMCID: PMC3990385 DOI: 10.1042/bst20130088] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The unique feature of mitochondrial complex I is the so-called A/D transition (active–deactive transition). The A-form catalyses rapid oxidation of NADH by ubiquinone (k ~104 min−1) and spontaneously converts into the D-form if the enzyme is idle at physiological temperatures. Such deactivation occurs in vitro in the absence of substrates or in vivo during ischaemia, when the ubiquinone pool is reduced. The D-form can undergo reactivation given both NADH and ubiquinone availability during slow (k ~1–10 min−1) catalytic turnover(s). We examined known conformational differences between the two forms and suggested a mechanism exerting A/D transition of the enzyme. In addition, we discuss the physiological role of maintaining the enzyme in the D-form during the ischaemic period. Accumulation of the D-form of the enzyme would prevent reverse electron transfer from ubiquinol to FMN which could lead to superoxide anion generation. Deactivation would also decrease the initial burst of respiration after oxygen reintroduction. Therefore the A/D transition could be an intrinsic protective mechanism for lessening oxidative damage during the early phase of reoxygenation. Exposure of Cys39 of mitochondrially encoded subunit ND3 makes the D-form susceptible for modification by reactive oxygen species and nitric oxide metabolites which arrests the reactivation of the D-form and inhibits the enzyme. The nature of thiol modification defines deactivation reversibility, the reactivation timescale, the status of mitochondrial bioenergetics and therefore the degree of recovery of the ischaemic tissues after reoxygenation.
Collapse
|
92
|
Mamou Z, Chahine M, Rhondali O, Dehina L, Chevalier P, Descotes J, Bui-Xuan B, Romestaing C, Timour Q. Effects of amlodipine and perindoprilate on the structure and function of mitochondria in ventricular cardiomyocytes during ischemia-reperfusion in the pig. Fundam Clin Pharmacol 2014; 29:21-30. [DOI: 10.1111/fcp.12070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 01/27/2014] [Accepted: 02/20/2014] [Indexed: 12/14/2022]
Affiliation(s)
- Zahida Mamou
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
| | - Mohamed Chahine
- Centre de recherche en neuroscience; Institut universitaire en santé mentale de Québec; Québec G1J 2G3 Canada
| | - Ossam Rhondali
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
| | - Leila Dehina
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
| | - Philippe Chevalier
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
| | - Jacques Descotes
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
- Poison Center and Pharmacovigilance Department; 162 Ave Lacassagne 69003 Lyon France
| | - Bernard Bui-Xuan
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
| | - Caroline Romestaing
- Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés; CNRS UMR 5023; Ave Albert Einstein 69100 Villeurbanne France
| | - Quadiri Timour
- EA 4612; Laboratory of Medical Pharmacology; Claude Bernard University; 69373 Lyon France
- Poison Center and Pharmacovigilance Department; 162 Ave Lacassagne 69003 Lyon France
| |
Collapse
|
93
|
Xu A, Szczepanek K, Maceyka MW, Ross T, Bowler E, Hu Y, Kenny B, Mehfoud C, Desai PN, Baumgarten CM, Chen Q, Lesnefsky EJ. Transient complex I inhibition at the onset of reperfusion by extracellular acidification decreases cardiac injury. Am J Physiol Cell Physiol 2014; 306:C1142-53. [PMID: 24696146 DOI: 10.1152/ajpcell.00241.2013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A reversible inhibition of mitochondrial respiration by complex I inhibition at the onset of reperfusion decreases injury in buffer-perfused hearts. Administration of acidic reperfusate for a brief period at reperfusion decreases cardiac injury. We asked if acidification treatment decreased cardiac injury during reperfusion by inhibiting complex I. Exposure of isolated mouse heart mitochondria to acidic buffer decreased the complex I substrate-stimulated respiration, whereas respiration with complex II substrates was unaltered. Evidence of the rapid and reversible inhibition of complex I by an acidic environment was obtained at the level of isolated complex, intact mitochondria and in situ mitochondria in digitonin-permeabilized cardiac myocytes. Moreover, ischemia-damaged complex I was also reversibly inhibited by an acidic environment. In the buffer-perfused mouse heart, reperfusion with pH 6.6 buffer for the initial 5 min decreased infarction. Compared with untreated hearts, acidification treatment markedly decreased the mitochondrial generation of reactive oxygen species and improved mitochondrial calcium retention capacity and inner mitochondrial membrane integrity. The decrease in infarct size achieved by acidic reperfusion approximates the reduction obtained by a reversible, partial blockade of complex I at reperfusion. Extracellular acidification decreases cardiac injury during reperfusion in part via the transient and reversible inhibition of complex I, leading to a reduction of oxyradical generation accompanied by a decreased susceptibility to mitochondrial permeability transition during early reperfusion.
Collapse
Affiliation(s)
- Aijun Xu
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia; Department of Anesthesiology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, China; and
| | - Karol Szczepanek
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Michael W Maceyka
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Thomas Ross
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Elizabeth Bowler
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia; University of the West of England, Bristol, United Kingdom
| | - Ying Hu
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Barrett Kenny
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Chris Mehfoud
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Pooja N Desai
- Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Clive M Baumgarten
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia; Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Qun Chen
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia
| | - Edward J Lesnefsky
- Department of Medicine, Division of Cardiology, Pauley Heart Center, Virginia Commonwealth University School of Medicine, Richmond, Virginia; Department of Biochemistry and Molecular Biology, Virginia Commonwealth University School of Medicine, Richmond, Virginia; Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, Virginia; McGuire Veterans Affairs Medical Center, Richmond, Virginia;
| |
Collapse
|
94
|
Babot M, Birch A, Labarbuta P, Galkin A. Characterisation of the active/de-active transition of mitochondrial complex I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:1083-92. [PMID: 24569053 PMCID: PMC4331042 DOI: 10.1016/j.bbabio.2014.02.018] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 02/14/2014] [Accepted: 02/17/2014] [Indexed: 12/12/2022]
Abstract
Oxidation of NADH in the mitochondrial matrix of aerobic cells is catalysed by mitochondrial complex I. The regulation of this mitochondrial enzyme is not completely understood. An interesting characteristic of complex I from some organisms is the ability to adopt two distinct states: the so-called catalytically active (A) and the de-active, dormant state (D). The A-form in situ can undergo de-activation when the activity of the respiratory chain is limited (i.e. in the absence of oxygen). The mechanisms and driving force behind the A/D transition of the enzyme are currently unknown, but several subunits are most likely involved in the conformational rearrangements: the accessory subunit 39 kDa (NDUFA9) and the mitochondrially encoded subunits, ND3 and ND1. These three subunits are located in the region of the quinone binding site. The A/D transition could represent an intrinsic mechanism which provides a fast response of the mitochondrial respiratory chain to oxygen deprivation. The physiological role of the accumulation of the D-form in anoxia is most probably to protect mitochondria from ROS generation due to the rapid burst of respiration following reoxygenation. The de-activation rate varies in different tissues and can be modulated by the temperature, the presence of free fatty acids and divalent cations, the NAD+/NADH ratio in the matrix, the presence of nitric oxide and oxygen availability. Cysteine-39 of the ND3 subunit, exposed in the D-form, is susceptible to covalent modification by nitrosothiols, ROS and RNS. The D-form in situ could react with natural effectors in mitochondria or with pharmacological agents. Therefore the modulation of the re-activation rate of complex I could be a way to ameliorate the ischaemia/reperfusion damage. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference. Guest Editors: Manuela Pereira and Miguel Teixeira. The potential mechanism of complex I A/D transition is discussed. An —SH group exposed in the D-form is susceptible to covalent modification. The role of A/D transition in tissue response to ischaemia is proposed.
Collapse
Affiliation(s)
- Marion Babot
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Amanda Birch
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Paola Labarbuta
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK
| | - Alexander Galkin
- Queen's University Belfast, School of Biological Sciences, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
| |
Collapse
|
95
|
|
96
|
Zhao S, Lin Q, Li H, He Y, Fang X, Chen F, Chen C, Huang Z. Carbon monoxide releasing molecule‑2 attenuated ischemia/reperfusion‑induced apoptosis in cardiomyocytes via a mitochondrial pathway. Mol Med Rep 2013; 9:754-62. [PMID: 24337106 DOI: 10.3892/mmr.2013.1861] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 11/27/2013] [Indexed: 11/06/2022] Open
Abstract
Carbon monoxide (CO) is an endogenous gaseous transmitter that exerts multi-protection in ischemia/reperfusion (I/R) injury, but few experimental studies regarding CO on myocardial I/R-induced apoptosis, as well as its underlying mechanism have been conducted. The present study was designed to investigate whether CO released from CO-releasing molecule-2 (CORM-2) is capable of ameliorating myocardial I/R-induced apoptosis via a mitochondrial apoptotic pathway. Primary cultures of neonatal rat cardiomyocytes were randomly distributed into four groups: Control, I/R (cultured cardiomyocytes were subjected to 2 h simulated ischemia followed by 4 h reperfusion), CORM-2 and inactive CORM-2 (iCORM-2) groups (20 µM CORM-2 and 20 µM iCORM-2 were administered at the beginning of reperfusion following ischemia, respectively). Flow cytometric analysis showed that CORM-2 treatment significantly decreased apoptosis of cardiomyocytes triggered by simulated I/R. CORM-2 partially recovered mitochondrial respiration and ultrastructure alteration, and lowered caspase-3 expression and the release of cytochrome c. Furthermore, CORM-2 partly reduced BAK/BAX expression in mitochondria, as well as the BAX level in the cytoplasm. Cardioprotection is lost when CORM-2 is replaced by iCORM-2. CORM-2 treatment, at the time of reperfusion, was concluded to attenuate myocardial I/R-induced apoptosis. The protection mechanisms may be targeted to the mitochondria and involved in the inhibition of the BAK/BAX‑mediated intrinsic pathway.
Collapse
Affiliation(s)
- Shen Zhao
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Qingming Lin
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Heng Li
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Yumin He
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Xiangshao Fang
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| | - Feng Chen
- Provincial Clinical Medical College of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Changwei Chen
- Taiping People's Hospital of Dongguan City, Dongguan, Guangdong 523900, P.R. China
| | - Zitong Huang
- Department of Emergency, Sun Yat‑sen Memorial Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510120, P.R. China
| |
Collapse
|
97
|
|
98
|
Cyclosporine A at reperfusion fails to reduce infarct size in the in vivo rat heart. Basic Res Cardiol 2013; 108:379. [DOI: 10.1007/s00395-013-0379-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 07/04/2013] [Accepted: 08/06/2013] [Indexed: 01/25/2023]
|
99
|
Xu A, Szczepanek K, Hu Y, Lesnefsky EJ, Chen Q. Cardioprotection by modulation of mitochondrial respiration during ischemia-reperfusion: role of apoptosis-inducing factor. Biochem Biophys Res Commun 2013; 435:627-33. [PMID: 23685150 DOI: 10.1016/j.bbrc.2013.05.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/08/2013] [Indexed: 10/26/2022]
Abstract
The transient, reversible blockade of electron transport (BET) during ischemia or at the onset of reperfusion protects mitochondria and decreases cardiac injury. Apoptosis inducing factor (AIF) is located within the mitochondrial intermembrane space. A release of AIF from mitochondria into cytosol and nucleus triggers caspase-independent cell death. We asked if BET prevents the loss of AIF from mitochondria as a mechanism of protection in the buffer perfused heart. BET during ischemia with amobarbital, a rapidly reversible inhibitor of mitochondrial complex I, attenuated a release of AIF from mitochondria into cytosol, in turn decreasing the formation of cleaved and activated PARP-1. These results suggest that BET-mediated protection may occur through prevention of the loss of AIF from mitochondria during ischemia-reperfusion. In order to further clarify the role of mitochondrial AIF in BET-mediated protection, Harlequin (Hq) mice, a genetic model with mitochondrial AIF deficiency, were used to test whether BET could still decrease cell injury in Hq mouse hearts during reperfusion. BET during ischemia protected Hq mouse hearts against ischemia-reperfusion injury and improved mitochondrial function in these hearts during reperfusion. Thus, cardiac injury can still be decreased in the presence of down-regulated mitochondrial AIF content. Taken together, BET during ischemia protects both hearts with normal mitochondrial AIF content and hearts with mitochondrial AIF deficiency. Although preservation of mitochondrial AIF content plays a key role in reducing cell injury during reperfusion, the protection derived from the BET is not fully dependent on AIF-driven mechanisms.
Collapse
Affiliation(s)
- Aijun Xu
- Department of Internal Medicine (Division of Cardiology), Virginia Commonwealth University, Richmond, VA 23298, USA
| | | | | | | | | |
Collapse
|
100
|
Ross T, Szczepanek K, Bowler E, Hu Y, Larner A, Lesnefsky EJ, Chen Q. Reverse electron flow-mediated ROS generation in ischemia-damaged mitochondria: role of complex I inhibition vs. depolarization of inner mitochondrial membrane. Biochim Biophys Acta Gen Subj 2013; 1830:4537-42. [PMID: 23747300 DOI: 10.1016/j.bbagen.2013.05.035] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 05/17/2013] [Accepted: 05/27/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND The reverse electron flow-induced ROS generation (RFIR) is decreased in ischemia-damaged mitochondria. Cardiac ischemia leads to decreased complex I activity and depolarized inner mitochondrial membrane potential (ΔΨ) that are two key factors to affect the RFIR in isolated mitochondria. We asked if a partial inhibition of complex I activity without alteration of the ΔΨ is able to decrease the RFIR. METHODS Cardiac mitochondria were isolated from mouse heart (C57BL/6) with and without ischemia. The rate of H2O2 production from mitochondria was determined using amplex red coupled with horseradish peroxidase. Mitochondria were isolated from the mitochondrial-targeted STAT3 overexpressing mouse (MLS-STAT3E) to clarify the role of partial complex I inhibition in RFIR production. RESULTS The RFIR was decreased in ischemia-damaged mouse heart mitochondria with decreased complex I activity and depolarized ΔΨ. However, the RFIR was not altered in the MLS-STAT3E heart mitochondria with complex I defect but without depolarization of the ΔΨ. A slight depolarization of the ΔΨ in wild type mitochondria completely eliminated the RFIR. CONCLUSIONS The mild uncoupling but not the partially decreased complex I activity contributes to the observed decrease in RFIR in ischemia-damaged mitochondria. GENERAL SIGNIFICANCE The RFIR is less likely to be a key source of cardiac injury during reperfusion.
Collapse
Affiliation(s)
- Thomas Ross
- Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | | | | | | | | | | | | |
Collapse
|