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Whitcomb LA, Cao X, Thomas D, Wiese C, Pessin AS, Zhang R, Wu JC, Weil MM, Chicco AJ. Mitochondrial reactive oxygen species impact human fibroblast responses to protracted γ-ray exposures. Int J Radiat Biol 2024; 100:890-902. [PMID: 38631047 DOI: 10.1080/09553002.2024.2338518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 03/26/2024] [Indexed: 04/19/2024]
Abstract
Purpose: Continuous exposure to ionizing radiation at a low dose rate poses significant health risks to humans on deep space missions, prompting the need for mechanistic studies to identify countermeasures against its deleterious effects. Mitochondria are a major subcellular locus of radiogenic injury, and may trigger secondary cellular responses through the production of reactive oxygen species (mtROS) with broader biological implications. Methods and Materials: To determine the contribution of mtROS to radiation-induced cellular responses, we investigated the impacts of protracted γ-ray exposures (IR; 1.1 Gy delivered at 0.16 mGy/min continuously over 5 days) on mitochondrial function, gene expression, and the protein secretome of human HCA2-hTERT fibroblasts in the presence and absence of a mitochondria-specific antioxidant mitoTEMPO (MT; 5 µM). Results: IR increased fibroblast mitochondrial oxygen consumption (JO2) and H2O2 release rates (JH2O2) under energized conditions, which corresponded to higher protein expression of NADPH Oxidase (NOX) 1, NOX4, and nuclear DNA-encoded subunits of respiratory chain Complexes I and III, but depleted mtDNA transcripts encoding subunits of the same complexes. This was associated with activation of gene programs related to DNA repair, oxidative stress, and protein ubiquination, all of which were attenuated by MT treatment along with radiation-induced increases in JO2 and JH2O2. IR also increased secreted levels of interleukin-8 and Type I collagens, while decreasing Type VI collagens and enzymes that coordinate assembly and remodeling of the extracellular matrix. MT treatment attenuated many of these effects while augmenting others, revealing complex effects of mtROS in fibroblast responses to IR. Conclusion: These results implicate mtROS production in fibroblast responses to protracted radiation exposure, and suggest potentially protective effects of mitochondrial-targeted antioxidants against radiogenic tissue injury in vivo.
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Affiliation(s)
- Luke A Whitcomb
- Department of Biomedical Sciences, Colorado State University, CO, USA
| | - Xu Cao
- Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
| | - Dilip Thomas
- Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, CO, USA
| | - Alissa S Pessin
- Department of Biomedical Sciences, Colorado State University, CO, USA
| | - Robert Zhang
- Department of Biomedical Sciences, Colorado State University, CO, USA
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
| | - Michael M Weil
- Department of Environmental and Radiological Health Sciences, Colorado State University, CO, USA
| | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, CO, USA
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Coulson SZ, Guglielmo CG, Staples JF. Migration increases mitochondrial oxidative capacity without increasing reactive oxygen species emission in a songbird. J Exp Biol 2024; 227:jeb246849. [PMID: 38632979 PMCID: PMC11128287 DOI: 10.1242/jeb.246849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 04/10/2024] [Indexed: 04/19/2024]
Abstract
Birds remodel their flight muscle metabolism prior to migration to meet the physiological demands of migratory flight, including increases in both oxidative capacity and defence against reactive oxygen species. The degree of plasticity mediated by changes in these mitochondrial properties is poorly understood but may be explained by two non-mutually exclusive hypotheses: variation in mitochondrial quantity or in individual mitochondrial function. We tested these hypotheses using yellow-rumped warblers (Setophaga coronata), a Nearctic songbird which biannually migrates 2000-5000 km. We predicted higher flight muscle mitochondrial abundance and substrate oxidative capacity, and decreased reactive oxygen species emission in migratory warblers captured during autumn migration compared with a short-day photoperiod-induced non-migratory phenotype. We assessed mitochondrial abundance via citrate synthase activity and assessed isolated mitochondrial function using high-resolution fluororespirometry. We found 60% higher tissue citrate synthase activity in the migratory phenotype, indicating higher mitochondrial abundance. We also found 70% higher State 3 respiration (expressed per unit citrate synthase) in mitochondria from migratory warblers when oxidizing palmitoylcarnitine, but similar H2O2 emission rates between phenotypes. By contrast, non-phosphorylating respiration was higher and H2O2 emission rates were lower in the migratory phenotype. However, flux through electron transport system complexes I-IV, II-IV and IV was similar between phenotypes. In support of our hypotheses, these data suggest that flight muscle mitochondrial abundance and function are seasonally remodelled in migratory songbirds to increase tissue oxidative capacity without increasing reactive oxygen species formation.
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Affiliation(s)
- Soren Z. Coulson
- Department of Biology, Western University, London, ON, Canada, N6A 5B7
- Centre for Animals on the Move, Western University, London, ON, Canada, N6A 3K7
| | - Christopher G. Guglielmo
- Department of Biology, Western University, London, ON, Canada, N6A 5B7
- Centre for Animals on the Move, Western University, London, ON, Canada, N6A 3K7
| | - James F. Staples
- Department of Biology, Western University, London, ON, Canada, N6A 5B7
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Coulson SZ, Duffy BM, Staples JF. Mitochondrial techniques for physiologists. Comp Biochem Physiol B Biochem Mol Biol 2024; 271:110947. [PMID: 38278207 DOI: 10.1016/j.cbpb.2024.110947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 01/28/2024]
Abstract
Mitochondria serve several important roles in maintaining cellular homeostasis, including adenosine triphosphate (ATP) synthesis, apoptotic signalling, and regulation of both reactive oxygen species (ROS) and calcium. Therefore, mitochondrial studies may reveal insights into metabolism at higher levels of physiological organization. The apparent complexity of mitochondrial function may be daunting to researchers new to mitochondrial physiology. This review is aimed, therefore, at such researchers to provide a brief, yet approachable overview of common techniques used to assess mitochondrial function. Here we discuss the use of high-resolution respirometry in mitochondrial experiments and common analytical platforms used for this technique. Next, we compare the use of common mitochondrial preparation techniques, including adherent cells, tissue homogenate, permeabilized fibers and isolated mitochondria. Finally, we outline additional techniques that can be used in tandem with high-resolution respirometry to assess additional aspects of mitochondrial metabolism, including ATP synthesis, calcium uptake, membrane potential and reactive oxygen species emission. We also include limitations to each of these techniques and outline recommendations for experimental design and interpretation. With a general understanding of methodologies commonly used to study mitochondrial physiology, experimenters may begin contributing to our understanding of this organelle, and how it affects other physiological phenotypes.
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Affiliation(s)
- Soren Z Coulson
- Department of Biology, University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada.
| | - Brynne M Duffy
- Department of Biology, University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada. https://twitter.com/BrynneDuffy
| | - James F Staples
- Department of Biology, University of Western Ontario, 1151 Richmond Street, London, Ontario, Canada
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Catandi GD, Fresa KJ, Cheng MH, Whitcomb LA, Broeckling CD, Chen TW, Chicco AJ, Carnevale EM. Follicular metabolic alterations are associated with obesity in mares and can be mitigated by dietary supplementation. Sci Rep 2024; 14:7571. [PMID: 38555310 PMCID: PMC10981747 DOI: 10.1038/s41598-024-58323-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 03/27/2024] [Indexed: 04/02/2024] Open
Abstract
Obesity is a growing concern in human and equine populations, predisposing to metabolic pathologies and reproductive disturbances. Cellular lipid accumulation and mitochondrial dysfunction play an important role in the pathologic consequences of obesity, which may be mitigated by dietary interventions targeting these processes. We hypothesized that obesity in the mare promotes follicular lipid accumulation and altered mitochondrial function of oocytes and granulosa cells, potentially contributing to impaired fertility in this population. We also predicted that these effects could be mitigated by dietary supplementation with a combination of targeted nutrients to improve follicular cell metabolism. Twenty mares were grouped as: Normal Weight [NW, n = 6, body condition score (BCS) 5.7 ± 0.3], Obese (OB, n = 7, BCS 7.7 ± 0.2), and Obese Diet Supplemented (OBD, n = 7, BCS 7.7 ± 0.2), and fed specific feed regimens for ≥ 6 weeks before sampling. Granulosa cells, follicular fluid, and cumulus-oocyte complexes were collected from follicles ≥ 35 mm during estrus and after induction of maturation. Obesity promoted several mitochondrial metabolic disturbances in granulosa cells, reduced L-carnitine availability in the follicle, promoted lipid accumulation in cumulus cells and oocytes, and increased basal oocyte metabolism. Diet supplementation of a complex nutrient mixture mitigated most of the metabolic changes in the follicles of obese mares, resulting in parameters similar to NW mares. In conclusion, obesity disturbs the equine ovarian follicle by promoting lipid accumulation and altering mitochondrial function. These effects may be partially mitigated with targeted nutritional intervention, thereby potentially improving fertility outcomes in the obese female.
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Affiliation(s)
- Giovana D Catandi
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
- Department of Veterinary Clinical Sciences, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Kyle J Fresa
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Ming-Hao Cheng
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, 80523, USA
| | - Luke A Whitcomb
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Corey D Broeckling
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, 80523, USA
| | - Thomas W Chen
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, 80523, USA
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, 80523, USA
| | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Elaine M Carnevale
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
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Frei DR, Moore MR, Bailey M, Beasley R, Campbell D, Leslie K, Myles PS, Short TG, Young PJ. Associations between the intraoperative fraction of inspired intraoperative oxygen administration and days alive and out of hospital after surgery. BJA OPEN 2024; 9:100253. [PMID: 38304283 PMCID: PMC10832366 DOI: 10.1016/j.bjao.2023.100253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 12/16/2023] [Indexed: 02/03/2024]
Abstract
Background There is limited knowledge about the effect of liberal intraoperative oxygen on non-infectious complications and overall recovery from surgery. Methods In this retrospective cohort study, we investigated associations between mean intraoperative fraction of inspired oxygen (FiO2), and outcome in adults undergoing elective surgery lasting more than 2 h at a large metropolitan New Zealand hospital from 2012 to 2020. Patients were divided into low, medium, and high oxygen groups (FiO2 ≤ 0.4, 0.41-0.59, ≥0.6). The primary outcome was days alive and out of hospital at 90 days (DAOH90). The secondary outcomes were post-operative complications and admission to the ICU. Results We identified 15,449 patients who met the inclusion criteria. There was no association between FiO2 and DAOH90 when high FiO2 was analysed according to three groups. Using high FiO2 as the reference group there was an adjusted mean (95% confidence interval [CI]) difference of 0.09 (-0.06 to 0.25) days (P = 0.25) and 0.28 (-0.05 to 0.62) days (P = 0.2) in the intermediate and low oxygen groups, respectively. Low FiO2 was associated with increased surgical site infection: the adjusted odds ratio (OR) for low compared with high FiO2 was 1.53 (95% CI 1.12-2.10). Increasing FiO2 was associated with respiratory complications: the adjusted OR associated with each 10% point increase in FiO2 was 1.17 (95% CI 1.08-1.26) and the incidence of being admitted to an ICU had an adjusted OR of 1.1 (95% CI 1.03-1.18). Conclusions We found potential benefits, and risks, associated with liberal intraoperative oxygen administration indicating that randomised controlled trials are warranted.
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Affiliation(s)
- Daniel R. Frei
- Department of Anaesthesia and Pain Management, Wellington Hospital, Wellington, New Zealand
- Medical Research Institute of New Zealand, Wellington, New Zealand
| | - Matthew R. Moore
- Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
| | - Michael Bailey
- Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Richard Beasley
- Medical Research Institute of New Zealand, Wellington, New Zealand
- Victoria University of Wellington, Wellington, New Zealand
| | - Douglas Campbell
- Department of Anaesthesiology, University of Auckland, Auckland, New Zealand
- Department of Anaesthesia and Peri-operative Medicine, Auckland City Hospital, Auckland, New Zealand
| | - Kate Leslie
- Department of Anaesthesia and Pain Management, Royal Melbourne Hospital, Melbourne, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Melbourne, Victoria, Australia
- Department of Anaesthesiology and Perioperative Medicine, Central Clinical School, Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, Victoria, Australia
| | - Paul S. Myles
- Department of Anaesthesiology and Perioperative Medicine, Central Clinical School, Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, Victoria, Australia
- Department of Anaesthesiology and Perioperative Medicine, Alfred Hospital Melbourne, Victoria, Australia
| | - Timothy G. Short
- Medical Research Institute of New Zealand, Wellington, New Zealand
- Department of Anaesthesia and Peri-operative Medicine, Auckland City Hospital, Auckland, New Zealand
| | - Paul J. Young
- Medical Research Institute of New Zealand, Wellington, New Zealand
- Australian and New Zealand Intensive Care Research Centre, Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
- Department of Critical Care, Melbourne Medical School, University of Melbourne, Melbourne, Victoria, Australia
- Department of Intensive Care, Wellington Regional Hospital, Wellington, New Zealand
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Cao X, Thomas D, Whitcomb LA, Wang M, Chatterjee A, Chicco AJ, Weil MM, Wu JC. Modeling ionizing radiation-induced cardiovascular dysfunction with human iPSC-derived engineered heart tissues. J Mol Cell Cardiol 2024; 188:105-107. [PMID: 38431383 PMCID: PMC10961094 DOI: 10.1016/j.yjmcc.2023.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/28/2023] [Accepted: 11/30/2023] [Indexed: 03/05/2024]
Affiliation(s)
- Xu Cao
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, United States of America; Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, United States of America
| | - Dilip Thomas
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, United States of America; Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, United States of America
| | - Luke A Whitcomb
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, United States of America
| | - Mingqiang Wang
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, United States of America; Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, United States of America
| | - Anushree Chatterjee
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, CO 80303, United States of America
| | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, United States of America.
| | - Michael M Weil
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, United States of America.
| | - Joseph C Wu
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA 94305, United States of America; Division of Cardiovascular Medicine, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, United States of America; Greenstone Biosciences, Palo Alto, CA 94304, United States of America.
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Omar AK, Li Puma LC, Whitcomb LA, Risk BD, Witt AC, Bruemmer JE, Winger QA, Bouma GJ, Chicco AJ. High-fat diet during pregnancy promotes fetal skeletal muscle fatty acid oxidation and insulin resistance in an ovine model. Am J Physiol Regul Integr Comp Physiol 2023; 325:R523-R533. [PMID: 37642284 DOI: 10.1152/ajpregu.00059.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 08/11/2023] [Accepted: 08/24/2023] [Indexed: 08/31/2023]
Abstract
Maternal diet during pregnancy is associated with offspring metabolic risk trajectory in humans and animal models, but the prenatal origins of these effects are less clear. We examined the effects of a high-fat diet (HFD) during pregnancy on fetal skeletal muscle metabolism and metabolic risk parameters using an ovine model. White-faced ewes were fed a standardized diet containing 5% fat wt/wt (CON), or the same diet supplemented with 6% rumen-protected fats (11% total fat wt/wt; HFD) beginning 2 wk before mating until midgestation (GD75). Maternal HFD increased maternal weight gain, fetal body weight, and low-density lipoprotein levels in the uterine and umbilical circulation but had no significant effects on circulating glucose, triglycerides, or placental fatty acid transporters. Fatty acid (palmitoylcarnitine) oxidation capacity of permeabilized hindlimb muscle fibers was >50% higher in fetuses from HFD pregnancies, whereas pyruvate and maximal (mixed substrate) oxidation capacities were similar to CON. This corresponded to greater triacylglycerol content and protein expression of fatty acid transport and oxidation enzymes in fetal muscle but no significant effect on respiratory chain complexes or pyruvate dehydrogenase expression. However, serine-308 phosphorylation of insulin receptor substrate-1 was greater in fetal muscle from HFD pregnancies along with c-jun-NH2 terminal kinase activation, consistent with prenatal inhibition of skeletal muscle insulin signaling. These results indicate that maternal high-fat feeding shifts fetal skeletal muscle metabolism toward a greater capacity for fatty acid over glucose utilization and favors prenatal development of insulin resistance, which may predispose offspring to metabolic syndrome later in life.NEW & NOTEWORTHY Maternal diet during pregnancy is associated with offspring metabolic risk trajectory in humans and animal models, but the prenatal origins of these effects are less clear. This study examined the effects of a high-fat diet during pregnancy on metabolic risk parameters using a new sheep model. Results align with findings previously reported in nonhuman primates, demonstrating changes in fetal skeletal muscle metabolism that may predispose offspring to metabolic syndrome later in life.
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Affiliation(s)
- Asma K Omar
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Lance C Li Puma
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Luke A Whitcomb
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Briana D Risk
- Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, Colorado, United States
| | - Aria C Witt
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Jason E Bruemmer
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Quinton A Winger
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Gerrit J Bouma
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
| | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States
- Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, Colorado, United States
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Fletcher E, Miserlis D, Sorokolet K, Wilburn D, Bradley C, Papoutsi E, Wilkinson T, Ring A, Ferrer L, Haynatzki G, Smith RS, Bohannon WT, Koutakis P. Diet-induced obesity augments ischemic myopathy and functional decline in a murine model of peripheral artery disease. Transl Res 2023; 260:17-31. [PMID: 37220835 DOI: 10.1016/j.trsl.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 05/25/2023]
Abstract
Peripheral artery disease (PAD) causes an ischemic myopathy contributing to patient disability and mortality. Most preclinical models to date use young, healthy rodents with limited translatability to human disease. Although PAD incidence increases with age, and obesity is a common comorbidity, the pathophysiologic association between these risk factors and PAD myopathy is unknown. Using our murine model of PAD, we sought to elucidate the combined effect of age, diet-induced obesity and chronic hindlimb ischemia (HLI) on (1) mobility, (2) muscle contractility, and markers of muscle (3) mitochondrial content and function, (4) oxidative stress and inflammation, (5) proteolysis, and (6) cytoskeletal damage and fibrosis. Following 16-weeks of high-fat, high-sucrose, or low-fat, low-sucrose feeding, HLI was induced in 18-month-old C57BL/6J mice via the surgical ligation of the left femoral artery at 2 locations. Animals were euthanized 4-weeks post-ligation. Results indicate mice with and without obesity shared certain myopathic changes in response to chronic HLI, including impaired muscle contractility, altered mitochondrial electron transport chain complex content and function, and compromised antioxidant defense mechanisms. However, the extent of mitochondrial dysfunction and oxidative stress was significantly greater in obese ischemic muscle compared to non-obese ischemic muscle. Moreover, functional impediments, such as delayed post-surgical recovery of limb function and reduced 6-minute walking distance, as well as accelerated intramuscular protein breakdown, inflammation, cytoskeletal damage, and fibrosis were only evident in mice with obesity. As these features are consistent with human PAD myopathy, our model could be a valuable tool to test new therapeutics.
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Affiliation(s)
- Emma Fletcher
- Department of Biology, Baylor University, Waco, Texas
| | - Dimitrios Miserlis
- Department of Surgery, University of Texas at Austin Dell Medical School, Austin, Texas
| | | | - Dylan Wilburn
- Department of Health, Human Performance and Recreation, Baylor University, Waco, Texas
| | | | | | | | - Andrew Ring
- Department of Biology, Baylor University, Waco, Texas
| | - Lucas Ferrer
- Department of Surgery, University of Texas at Austin Dell Medical School, Austin, Texas
| | - Gleb Haynatzki
- Department of Biostatistics, University of Nebraska Medical Center, Omaha, Nebraska
| | - Robert S Smith
- Department of Surgery, Baylor Scott & White Medical Center, Temple, Texas
| | - William T Bohannon
- Department of Surgery, Baylor Scott & White Medical Center, Temple, Texas
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Parsons AM, Rajendran RR, Whitcomb LA, Bouma GJ, Chicco AJ. Characterization of trophoblast mitochondrial function and responses to testosterone treatment in ACH-3P cells. Placenta 2023; 137:70-77. [PMID: 37087951 DOI: 10.1016/j.placenta.2023.04.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/24/2023] [Accepted: 04/09/2023] [Indexed: 04/25/2023]
Abstract
INTRODUCTION Trophoblast mitochondria play important roles in placental energy metabolism, physiology and pathophysiology. Hyperandrogenism has been associated with mitochondrial abnormalities in pregnancy disorders such as pre-eclampsia, gestational diabetes, and intrauterine growth restriction, but the direct impacts of androgen exposure on placental mitochondrial function are unknown. Given the inherent limitations of studying the human placenta during pregnancy, trophoblast cell lines are routinely used to model placental biology in vitro. The aim of this study was to characterize mitochondrial respiratory function in four commonly used trophoblast cell lines to provide a basis for selecting one well-suited to investigating the impact of androgens on trophoblast mitochondrial function. METHODS Androgen receptor expression, mitochondrial respiration (JO2) and reactive oxygen species (ROS) release rates were evaluated in three human trophoblast cell lines (ACH-3P, BeWo and Swan-71) and one immortalized ovine trophoblast line (iOTR) under basal and substrate-stimulated conditions using high-resolution fluorespirometry. RESULTS ACH-3P cells exhibited the greatest mitochondrial respiratory capacity and coupling efficiency of the four trophoblast lines tested, along with robust expression of androgen receptor protein that was found to co-localize with mitochondria by immunoblot and immunofluorescence. Acute testosterone administration (10 nM) tended to decrease ACH-3P mitochondrial JO2 and increase ROS release, while chronic (7 days) testosterone exposure increased expression of mitochondrial proteins, JO2, and ROS release. DISCUSSION These studies establish ACH-3P as a suitable cell line for investigating trophoblast mitochondrial function, and provide foundational evidence supporting links between hyperandrogenism and placental mitochondrial ROS production with potential relevance to several common pregnancy disorders.
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Affiliation(s)
- Agata M Parsons
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Ranjitha Raja Rajendran
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Luke A Whitcomb
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Gerrit J Bouma
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Adam J Chicco
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
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McGowan EM, Ehrlicher SE, Stierwalt HD, Robinson MM, Newsom SA. Impact of 4 weeks of western diet and aerobic exercise training on whole-body phenotype and skeletal muscle mitochondrial respiration in male and female mice. Physiol Rep 2022; 10:e15543. [PMID: 36541261 PMCID: PMC9768729 DOI: 10.14814/phy2.15543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/13/2022] [Accepted: 11/14/2022] [Indexed: 12/24/2022] Open
Abstract
High dietary fat intake induces significant whole-body and skeletal muscle adaptations in mice, including increased capacity for fat oxidation and mitochondrial biogenesis. The impact of a diet that is high in fat and simple sugars (i.e., western diet [WD]), particularly on regulation of skeletal muscle mitochondrial function, is less understood. The purpose of the current study was to determine physiologic adaptations in mitochondrial respiratory capacity in skeletal muscle during short-term consumption of WD, including if adaptive responses to WD-feeding are modified by concurrent exercise training or may be sex-specific. Male and female C57BL/6J mice were randomized to consume low-fat diet (LFD) or WD for 4 weeks, with some WD-fed mice also performing concurrent treadmill training (WD + Ex). Group sizes were n = 4-7. Whole-body metabolism was measured using in-cage assessment of food intake and energy expenditure, DXA body composition analysis and insulin tolerance testing. High-resolution respirometry of mitochondria isolated from quadriceps muscle was used to determine skeletal muscle mitochondrial respiratory function. Male mice fed WD gained mass (p < 0.001), due to increased fat mass (p < 0.001), and displayed greater respiratory capacity for both lipid and non-lipid substrates compared with LFD mice (p < 0.05). There was no effect of concurrent treadmill training on maximal respiration (WD + Ex vs. WD). Female mice had non-significant changes in body mass and composition as a function of the interventions, and no differences in skeletal muscle mitochondrial oxidative capacity. These findings indicate 4 weeks of WD feeding can increase skeletal muscle mitochondrial oxidative capacity among male mice; whereas WD, with or without exercise, had minimal impact on mass gain and skeletal muscle respiratory capacity among female mice. The translational relevance is that mitochondrial adaptation to increases in dietary fat intake that model WD may be related to differences in weight gain among male and female mice.
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Affiliation(s)
- Erin M. McGowan
- School of Biological and Population Health Sciences, College of Public Health and Human SciencesOregon State UniversityCorvallisOregonUSA
| | - Sarah E. Ehrlicher
- School of Biological and Population Health Sciences, College of Public Health and Human SciencesOregon State UniversityCorvallisOregonUSA
| | - Harrison D. Stierwalt
- School of Biological and Population Health Sciences, College of Public Health and Human SciencesOregon State UniversityCorvallisOregonUSA
| | - Matthew M. Robinson
- School of Biological and Population Health Sciences, College of Public Health and Human SciencesOregon State UniversityCorvallisOregonUSA
| | - Sean A. Newsom
- School of Biological and Population Health Sciences, College of Public Health and Human SciencesOregon State UniversityCorvallisOregonUSA
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Nikolaou PE, Mylonas N, Makridakis M, Makrecka-Kuka M, Iliou A, Zerikiotis S, Efentakis P, Kampoukos S, Kostomitsopoulos N, Vilskersts R, Ikonomidis I, Lambadiari V, Zuurbier CJ, Latosinska A, Vlahou A, Dimitriadis G, Iliodromitis EK, Andreadou I. Cardioprotection by selective SGLT-2 inhibitors in a non-diabetic mouse model of myocardial ischemia/reperfusion injury: a class or a drug effect? Basic Res Cardiol 2022; 117:27. [PMID: 35581445 DOI: 10.1007/s00395-022-00934-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 05/04/2022] [Accepted: 05/04/2022] [Indexed: 02/08/2023]
Abstract
Major clinical trials with sodium glucose co-transporter-2 inhibitors (SGLT-2i) exhibit protective effects against heart failure events, whereas inconsistencies regarding the cardiovascular death outcomes are observed. Therefore, we aimed to compare the selective SGLT-2i empagliflozin (EMPA), dapagliflozin (DAPA) and ertugliflozin (ERTU) in terms of infarct size (IS) reduction and to reveal the cardioprotective mechanism in healthy non-diabetic mice. C57BL/6 mice randomly received vehicle, EMPA (10 mg/kg/day) and DAPA or ERTU orally at the stoichiometrically equivalent dose (SED) for 7 days. 24 h-glucose urinary excretion was determined to verify SGLT-2 inhibition. IS of the region at risk was measured after 30 min ischemia (I), and 120 min reperfusion (R). In a second series, the ischemic myocardium was collected (10th min of R) for shotgun proteomics and evaluation of the cardioprotective signaling. In a third series, we evaluated the oxidative phosphorylation capacity (OXPHOS) and the mitochondrial fatty acid oxidation capacity by measuring the respiratory rates. Finally, Stattic, the STAT-3 inhibitor and wortmannin were administered in both EMPA and DAPA groups to establish causal relationships in the mechanism of protection. EMPA, DAPA and ERTU at the SED led to similar SGLT-2 inhibition as inferred by the significant increase in glucose excretion. EMPA and DAPA but not ERTU reduced IS. EMPA preserved mitochondrial functionality in complex I&II linked oxidative phosphorylation. EMPA and DAPA treatment led to NF-kB, RISK, STAT-3 activation and the downstream apoptosis reduction coinciding with IS reduction. Stattic and wortmannin attenuated the cardioprotection afforded by EMPA and DAPA. Among several upstream mediators, fibroblast growth factor-2 (FGF-2) and caveolin-3 were increased by EMPA and DAPA treatment. ERTU reduced IS only when given at the double dose of the SED (20 mg/kg/day). Short-term EMPA and DAPA, but not ERTU administration at the SED reduce IS in healthy non-diabetic mice. Cardioprotection is not correlated to SGLT-2 inhibition, is STAT-3 and PI3K dependent and associated with increased FGF-2 and Cav-3 expression.
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Affiliation(s)
- Panagiota Efstathia Nikolaou
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece
| | - Nikolaos Mylonas
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece
| | - Manousos Makridakis
- Centre of Systems Biology, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece
| | | | - Aikaterini Iliou
- Faculty of Pharmacy, Section of Pharmaceutical Chemistry, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Stelios Zerikiotis
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece
| | - Panagiotis Efentakis
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece
| | - Stavros Kampoukos
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece
| | - Nikolaos Kostomitsopoulos
- Centre of Clinical Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece
| | | | - Ignatios Ikonomidis
- Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Vaia Lambadiari
- 2nd Department of Internal Medicine, Research Institute and Diabetes Center, National and Kapodistrian University of Athens, "Attikon" University Hospital, Athens, Greece
| | - Coert J Zuurbier
- Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Amsterdam Infection and Immunity, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | | | - Antonia Vlahou
- Centre of Systems Biology, Biomedical Research Foundation of the Academy of Athens (BRFAA), Athens, Greece
| | - George Dimitriadis
- 2nd Department of Internal Medicine, Research Institute and Diabetes Center, National and Kapodistrian University of Athens, "Attikon" University Hospital, Athens, Greece
| | | | - Ioanna Andreadou
- Laboratory of Pharmacology, Faculty of Pharmacy, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece.
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12
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Li X, Flynn ER, do Carmo JM, Wang Z, da Silva AA, Mouton AJ, Omoto ACM, Hall ME, Hall JE. Direct Cardiac Actions of Sodium-Glucose Cotransporter 2 Inhibition Improve Mitochondrial Function and Attenuate Oxidative Stress in Pressure Overload-Induced Heart Failure. Front Cardiovasc Med 2022; 9:859253. [PMID: 35647080 PMCID: PMC9135142 DOI: 10.3389/fcvm.2022.859253] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/15/2022] [Indexed: 12/21/2022] Open
Abstract
Clinical trials showed that sodium-glucose cotransporter 2 (SGLT2) inhibitors, a class of drugs developed for treating diabetes mellitus, improve prognosis of patients with heart failure (HF). However, the mechanisms for cardioprotection by SGLT2 inhibitors are still unclear. Mitochondrial dysfunction and oxidative stress play important roles in progression of HF. This study tested the hypothesis that empagliflozin (EMPA), a highly selective SGLT2 inhibitor, improves mitochondrial function and reduces reactive oxygen species (ROS) while enhancing cardiac performance through direct effects on the heart in a non-diabetic mouse model of HF induced by transverse aortic constriction (TAC). EMPA or vehicle was administered orally for 4 weeks starting 2 weeks post-TAC. EMPA treatment did not alter blood glucose or body weight but significantly attenuated TAC-induced cardiac dysfunction and ventricular remodeling. Impaired mitochondrial oxidative phosphorylation (OXPHOS) in failing hearts was significantly improved by EMPA. EMPA treatment also enhanced mitochondrial biogenesis and restored normal mitochondria morphology. Although TAC increased mitochondrial ROS and decreased endogenous antioxidants, EMPA markedly inhibited cardiac ROS production and upregulated expression of endogenous antioxidants. In addition, EMPA enhanced autophagy and decreased cardiac apoptosis in TAC-induced HF. Importantly, mitochondrial respiration significantly increased in ex vivo cardiac fibers after direct treatment with EMPA. Our results indicate that EMPA has direct effects on the heart, independently of reductions in blood glucose, to enhance mitochondrial function by upregulating mitochondrial biogenesis, enhancing OXPHOS, reducing ROS production, attenuating apoptosis, and increasing autophagy to improve overall cardiac function in a non-diabetic model of pressure overload-induced HF.
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Affiliation(s)
- Xuan Li
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, Mississippi Center for Heart Research, University of Mississippi Medical Center, Jackson, MS, United States
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13
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Wang E, Whitcomb LA, Chicco AJ, Wilson JW. Transient absorption spectroscopy and imaging of redox in muscle mitochondria. BIOMEDICAL OPTICS EXPRESS 2022; 13:2103-2116. [PMID: 35519286 PMCID: PMC9045930 DOI: 10.1364/boe.452559] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 03/03/2022] [Accepted: 03/03/2022] [Indexed: 06/14/2023]
Abstract
Mitochondrial redox is an important indicator of cell metabolism and health, with implications in cancer, diabetes, aging, neurodegenerative diseases, and mitochondrial disease. The most common method to observe redox of individual cells and mitochondria is through fluorescence of NADH and FAD+, endogenous cofactors serve as electron transport inputs to the mitochondrial respiratory chain. Yet this leaves out redox within the respiratory chain itself. To a degree, the missing information can be filled in by exogenous fluorophores, but at the risk of disturbed mitochondrial permeability and respiration. Here we show that variations in respiratory chain redox can be detected up by visible-wavelength transient absorption microscopy (TAM). In TAM, the selection of pump and probe wavelengths can provide multiphoton imaging contrast between non-fluorescent molecules. Here, we applied TAM with a pump at 520nm and probe at 450nm, 490nm, and 620nm to elicit redox contrast from mitochondrial respiratory chain hemeproteins. Experiments were performed with reduced and oxidized preparations of isolated mitochondria and whole muscle fibers, using mitochondrial fuels (malate, pyruvate, and succinate) to set up physiologically relevant oxidation levels. TAM images of muscle fibers were analyzed with multivariate curve resolution (MCR), revealing that the response at 620nm probe provides the best redox contrast and the most consistent response between whole cells and isolated mitochondria.
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Affiliation(s)
- Erkang Wang
- Department of Electrical & Computer
Engineering, Colorado State University,
1373 Campus Delivery, Fort Collins, CO 80523, USA
| | - Luke A. Whitcomb
- Department of Biomedical Sciences,
Colorado State University, 1601 Campus
Delivery, Fort Collins, CO 80523, USA
| | - Adam J. Chicco
- Department of Biomedical Sciences,
Colorado State University, 1601 Campus
Delivery, Fort Collins, CO 80523, USA
| | - Jesse W. Wilson
- Department of Electrical & Computer
Engineering, Colorado State University,
1373 Campus Delivery, Fort Collins, CO 80523, USA
- School of Biomedical Engineering,
Colorado State University, 1301 Campus
Delivery, Fort Collins, CO 80523, USA
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14
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Starr VJ, Dzialowski EM. Developing chicken cardiac muscle mitochondria are resistant to variations in incubation oxygen levels. Curr Res Physiol 2022; 5:151-157. [PMID: 35345510 PMCID: PMC8956876 DOI: 10.1016/j.crphys.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/05/2022] [Accepted: 03/14/2022] [Indexed: 11/25/2022] Open
Abstract
Background Chronic exposure to hypoxia during vertebrate development can produce abnormal cardiovascular morphology and function. The aim of this study was to examine cardiac mitochondria function in an avian model, the chicken, in response to embryonic development under hypoxic (15% O2), normoxic (21% O2), or hyperoxic (40% O2) incubation conditions. Methods Chicken embryos were incubated in hypoxia, normoxia, or hyperoxia beginning on day 5 of incubation through hatching. Cardiac mitochondria oxygen flux and reactive oxygen species production were measured in permeabilized cardiac fibers from externally pipped and 1-day post hatchlings. Results Altering oxygen during development had a large effect on body and heart masses of externally pipped embryos and 1-day old hatchlings. Hypoxic animals had smaller body masses and absolute heart masses, but proportionally similar sized hearts compared to normoxic animals during external pipping. Hyperoxic animals were larger with larger hearts than normoxic animals during external pipping. Mitochondrial oxygen flux in permeabilized cardiac muscle fibers revealed limited effects of developing under altered oxygen conditions, with only oxygen flux through cytochrome oxidase being lower in hypoxic hearts compared with hyperoxic hearts. Oxygen flux in leak and oxidative phosphorylation states were not affected by developmental oxygen levels. Mitochondrial reactive oxygen species production under leak and oxidative phosphorylation states studied did not differ between any developmental oxygen treatment. Conclusions These results suggest that cardiac mitochondria function of the developing chicken is not altered by developing in ovo under different oxygen levels. Chicken heart mass is influenced by oxygen availability during development. Cardiac mitochondria respiration was unchanged by developing under hypoxic or hyperoxic oxygen stress. Cardiac mitochondria ROS production was not altered by developmental oxygen stress.
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Key Words
- AA, Antimycin A
- ADP, adenosine diphosphate
- COX, cytochrome oxidase
- Cardiac mitochondria
- Chicken
- EP, external pipping
- GMP, glutamate, malate, and pyruvate
- Hyperoxia
- Hypoxia
- IP, internal pipping
- LEAK, mitochondrial leak respiration
- OMY, oligomycin
- OXPHOS, mitochondrial oxidative phosphorylation
- ROS, reactive oxygen species
- ROT, rotenone
- Reactive oxygen species
- S, succinate
- TMPD, N,N,N’,N’-tetramethyl-p-phenylenediamine
- dph, days post hatching
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Affiliation(s)
- Vanessa J Starr
- Developmental Integrative Biology, Department of Biological Sciences, 1155 Union Circle #305220, University of North Texas, Denton, TX, 76203, USA
| | - Edward M Dzialowski
- Developmental Integrative Biology, Department of Biological Sciences, 1155 Union Circle #305220, University of North Texas, Denton, TX, 76203, USA
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15
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Steffen JBM, Haider F, Sokolov EP, Bock C, Sokolova IM. Mitochondrial capacity and reactive oxygen species production during hypoxia and reoxygenation in the ocean quahog, Arctica islandica. J Exp Biol 2021; 224:272605. [PMID: 34697625 DOI: 10.1242/jeb.243082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 10/06/2021] [Indexed: 11/20/2022]
Abstract
Oxygen fluctuations are common in marine waters, and hypoxia-reoxygenation (H-R) stress can negatively affect mitochondrial metabolism. The long-lived ocean quahog, Arctica islandica, is known for its hypoxia tolerance associated with metabolic rate depression, yet the mechanisms that sustain mitochondrial function during oxygen fluctuations are not well understood. We used top-down metabolic control analysis (MCA) to determine aerobic capacity and control over oxygen flux in the mitochondria of quahogs exposed to short-term hypoxia (24 h <0.01% O2) and subsequent reoxygenation (1.5 h 21% O2) compared with normoxic control animals (21% O2). We demonstrated that flux capacity of the substrate oxidation and proton leak subsystems were not affected by hypoxia, while the capacity of the phosphorylation subsystem was enhanced during hypoxia associated with a depolarization of the mitochondrial membrane. Reoxygenation decreased the oxygen flux capacity of all three mitochondrial subsystems. Control over oxidative phosphorylation (OXPHOS) respiration was mostly exerted by substrate oxidation regardless of H-R stress, whereas control by the proton leak subsystem of LEAK respiration increased during hypoxia and returned to normoxic levels during reoxygenation. During hypoxia, reactive oxygen species (ROS) efflux was elevated in the LEAK state, whereas it was suppressed in the OXPHOS state. Mitochondrial ROS efflux returned to normoxic control levels during reoxygenation. Thus, mitochondria of A. islandica appear robust to hypoxia by maintaining stable substrate oxidation and upregulating phosphorylation capacity, but remain sensitive to reoxygenation. This mitochondrial phenotype might reflect adaptation of A. islandica to environments with unpredictable oxygen fluctuations and its behavioural preference for low oxygen levels.
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Affiliation(s)
- Jennifer B M Steffen
- Department of Marine Biology, Institute of Biological Sciences, University of Rostock, 18059 Rostock, Germany
| | - Fouzia Haider
- Department of Marine Biology, Institute of Biological Sciences, University of Rostock, 18059 Rostock, Germany
| | - Eugene P Sokolov
- Leibniz Institute for Baltic Research, Leibniz Science Campus Phosphorus Research Rostock, Warnemünde, 18119 Rostock, Germany
| | - Christian Bock
- Integrative Ecophysiology, Alfred-Wegener-Institute Helmholtz Centre for Polar and Marine Research, 27570 Bremerhaven, Germany
| | - Inna M Sokolova
- Department of Marine Biology, Institute of Biological Sciences, University of Rostock, 18059 Rostock, Germany.,Department of Maritime Systems, Interdisciplinary Faculty, University of Rostock, 18059 Rostock, Germany
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16
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Dambrova M, Zuurbier CJ, Borutaite V, Liepinsh E, Makrecka-Kuka M. Energy substrate metabolism and mitochondrial oxidative stress in cardiac ischemia/reperfusion injury. Free Radic Biol Med 2021; 165:24-37. [PMID: 33484825 DOI: 10.1016/j.freeradbiomed.2021.01.036] [Citation(s) in RCA: 71] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/12/2022]
Abstract
The heart is the most metabolically flexible organ with respect to the use of substrates available in different states of energy metabolism. Cardiac mitochondria sense substrate availability and ensure the efficiency of oxidative phosphorylation and heart function. Mitochondria also play a critical role in cardiac ischemia/reperfusion injury, during which they are directly involved in ROS-producing pathophysiological mechanisms. This review explores the mechanisms of ROS production within the energy metabolism pathways and focuses on the impact of different substrates. We describe the main metabolites accumulating during ischemia in the glucose, fatty acid, and Krebs cycle pathways. Hyperglycemia, often present in the acute stress condition of ischemia/reperfusion, increases cytosolic ROS concentrations through the activation of NADPH oxidase 2 and increases mitochondrial ROS through the metabolic overloading and decreased binding of hexokinase II to mitochondria. Fatty acid-linked ROS production is related to the increased fatty acid flux and corresponding accumulation of long-chain acylcarnitines. Succinate that accumulates during anoxia/ischemia is suggested to be the main source of ROS, and the role of itaconate as an inhibitor of succinate dehydrogenase is emerging. We discuss the strategies to modulate and counteract the accumulation of substrates that yield ROS and the therapeutic implications of this concept.
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Affiliation(s)
- Maija Dambrova
- Latvian Institute of Organic Synthesis, Riga, Latvia; Riga Stradins University, Riga, Latvia.
| | - Coert J Zuurbier
- Amsterdam UMC, University of Amsterdam, Laboratory of Experimental Intensive Care and Anesthesiology, Department of Anesthesiology, Amsterdam Cardiovascular Sciences, Meibergdreef 9, AZ 1105, Amsterdam, the Netherlands
| | - Vilmante Borutaite
- Neuroscience Institute, Lithuanian University of Health Sciences, Kaunas, Lithuania
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