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Jasbi P, Nikolich-Žugich J, Patterson J, Knox KS, Jin Y, Weinstock GM, Smith P, Twigg HL, Gu H. Targeted metabolomics reveals plasma biomarkers and metabolic alterations of the aging process in healthy young and older adults. GeroScience 2023; 45:3131-3146. [PMID: 37195387 PMCID: PMC10643785 DOI: 10.1007/s11357-023-00823-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 05/10/2023] [Indexed: 05/18/2023] Open
Abstract
With the exponential growth in the older population in the coming years, many studies have aimed to further investigate potential biomarkers associated with the aging process and its incumbent morbidities. Age is the largest risk factor for chronic disease, likely due to younger individuals possessing more competent adaptive metabolic networks that result in overall health and homeostasis. With aging, physiological alterations occur throughout the metabolic system that contribute to functional decline. In this cross-sectional analysis, a targeted metabolomic approach was applied to investigate the plasma metabolome of young (21-40y; n = 75) and older adults (65y + ; n = 76). A corrected general linear model (GLM) was generated, with covariates of gender, BMI, and chronic condition score (CCS), to compare the metabolome of the two populations. Among the 109 targeted metabolites, those associated with impaired fatty acid metabolism in the older population were found to be most significant: palmitic acid (p < 0.001), 3-hexenedioic acid (p < 0.001), stearic acid (p = 0.005), and decanoylcarnitine (p = 0.036). Derivatives of amino acid metabolism, 1-methlyhistidine (p = 0.035) and methylhistamine (p = 0.027), were found to be increased in the younger population and several novel metabolites were identified, such as cadaverine (p = 0.034) and 4-ethylbenzoic acid (p = 0.029). Principal component analysis was conducted and highlighted a shift in the metabolome for both groups. Receiver operating characteristic analyses of partial least squares-discriminant analysis models showed the candidate markers to be more powerful indicators of age than chronic disease. Pathway and enrichment analyses uncovered several pathways and enzymes predicted to underlie the aging process, and an integrated hypothesis describing functional characteristics of the aging process was synthesized. Compared to older participants, the young group displayed greater abundance of metabolites related to lipid and nucleotide synthesis; older participants displayed decreased fatty acid oxidation and reduced tryptophan metabolism, relative to the young group. As a result, we offer a better understanding of the aging metabolome and potentially reveal new biomarkers and predicted mechanisms for future study.
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Affiliation(s)
- Paniz Jasbi
- College of Health Solutions, Arizona State University, Phoenix, AZ, 85004, USA
- School of Molecular Sciences, Arizona State University, Tempe, AZ, 85281, USA
| | - Janko Nikolich-Žugich
- University of Arizona Center on Aging, University of Arizona, Tucson, AZ, 85724, USA
| | - Jeffrey Patterson
- College of Health Solutions, Arizona State University, Phoenix, AZ, 85004, USA
| | - Kenneth S Knox
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, University of Arizona, Tucson, AZ, 85724, USA
| | - Yan Jin
- College of Health Solutions, Arizona State University, Phoenix, AZ, 85004, USA
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL, 34987, USA
| | | | - Patricia Smith
- Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine, Indiana University Medical Center, 1120 West Michigan Street, CL 260A, Indianapolis, IN, 46202, USA
| | - Homer L Twigg
- Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine, Indiana University Medical Center, 1120 West Michigan Street, CL 260A, Indianapolis, IN, 46202, USA.
| | - Haiwei Gu
- College of Health Solutions, Arizona State University, Phoenix, AZ, 85004, USA.
- Center for Translational Science, Florida International University, 11350 SW Village Pkwy, Port St. Lucie, FL, 34987, USA.
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Riel EB, Jürs BC, Cordeiro S, Musinszki M, Schewe M, Baukrowitz T. The versatile regulation of K2P channels by polyanionic lipids of the phosphoinositide and fatty acid metabolism. J Gen Physiol 2022; 154:212926. [PMID: 34928298 PMCID: PMC8693234 DOI: 10.1085/jgp.202112989] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 12/01/2021] [Indexed: 12/29/2022] Open
Abstract
Work over the past three decades has greatly advanced our understanding of the regulation of Kir K+ channels by polyanionic lipids of the phosphoinositide (e.g., PIP2) and fatty acid metabolism (e.g., oleoyl-CoA). However, comparatively little is known regarding the regulation of the K2P channel family by phosphoinositides and by long-chain fatty acid–CoA esters, such as oleoyl-CoA. We screened 12 mammalian K2P channels and report effects of polyanionic lipids on all tested channels. We observed activation of members of the TREK, TALK, and THIK subfamilies, with the strongest activation by PIP2 for TRAAK and the strongest activation by oleoyl-CoA for TALK-2. By contrast, we observed inhibition for members of the TASK and TRESK subfamilies. Our results reveal that TASK-2 channels have both activatory and inhibitory PIP2 sites with different affinities. Finally, we provided evidence that PIP2 inhibition of TASK-1 and TASK-3 channels is mediated by closure of the recently identified lower X-gate as critical mutations within the gate (i.e., L244A, R245A) prevent PIP2-induced inhibition. Our findings establish that K+ channels of the K2P family are highly sensitive to polyanionic lipids, extending our knowledge of the mechanisms of lipid regulation and implicating the metabolism of these lipids as possible effector pathways to regulate K2P channel activity.
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Affiliation(s)
- Elena B Riel
- Institute of Physiology, Kiel University, Kiel, Germany
| | - Björn C Jürs
- Institute of Physiology, Kiel University, Kiel, Germany.,Medical School Hamburg, University of Applied Sciences and Medical University, Hamburg, Germany
| | | | | | - Marcus Schewe
- Institute of Physiology, Kiel University, Kiel, Germany
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Cecatto C, Amaral AU, Wajner A, Wajner SM, Castilho RF, Wajner M. Disturbance of mitochondrial functions associated with permeability transition pore opening induced by cis-5-tetradecenoic and myristic acids in liver of adolescent rats. Mitochondrion 2019; 50:1-13. [PMID: 31655165 DOI: 10.1016/j.mito.2019.09.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/11/2019] [Accepted: 09/23/2019] [Indexed: 12/30/2022]
Abstract
Patients affected by very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency commonly present liver dysfunction whose pathogenesis is poorly known. We demonstrate here that major metabolites accumulating in this disorder, namely cis-5-tetradecenoic acid (Cis-5) and myristic acid (Myr), markedly impair mitochondrial respiration, decreasing ATP production in liver mitochondrial preparations from adolescent rats. Other parameters of mitochondrial homeostasis such as membrane potential (ΔΨm) and Ca2+retention capacity were strongly compromised by these fatty acids, involving induction of mitochondrial permeability transition. The present data indicate that disruption of mitochondrial bioenergetics and Ca2+homeostasis may contribute to the liver dysfunction of VLCAD deficient patients.
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Affiliation(s)
- Cristiane Cecatto
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Alexandre Umpierrez Amaral
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Ciências Biológicas, Universidade Regional Integrada do Alto Uruguai e das Missões, Erechim, RS, Brazil
| | - Alessandro Wajner
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Simone Magagnin Wajner
- Departamento de Medicina Interna, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Roger Frigério Castilho
- Departamento de Patologia Clínica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Moacir Wajner
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil.
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Korbecki J, Bajdak-Rusinek K. The effect of palmitic acid on inflammatory response in macrophages: an overview of molecular mechanisms. Inflamm Res 2019; 68:915-932. [PMID: 31363792 PMCID: PMC6813288 DOI: 10.1007/s00011-019-01273-5] [Citation(s) in RCA: 233] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 02/06/2023] Open
Abstract
Palmitic acid is a saturated fatty acid whose blood concentration is elevated in obese patients. This causes inflammatory responses, where toll-like receptors (TLR), TLR2 and TLR4, play an important role. Nevertheless, palmitic acid is not only a TLR agonist. In the cell, this fatty acid is converted into phospholipids, diacylglycerol and ceramides. They trigger the activation of various signaling pathways that are common for LPS-mediated TLR4 activation. In particular, metabolic products of palmitic acid affect the activation of various PKCs, ER stress and cause an increase in ROS generation. Thanks to this, palmitic acid also strengthens the TLR4-induced signaling. In this review, we discuss the mechanisms of inflammatory response induced by palmitic acid. In particular, we focus on describing its effect on ER stress and IRE1α, and the mechanisms of NF-κB activation. We also present the mechanisms of inflammasome NLRP3 activation and the effect of palmitic acid on enhanced inflammatory response by increasing the expression of FABP4/aP2. Finally, we focus on the consequences of inflammatory responses, in particular, the effect of TNF-α, IL-1β and IL-6 on insulin resistance. Due to the high importance of macrophages and the production of proinflammatory cytokines by them, this work mainly focuses on these cells.
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Affiliation(s)
- Jan Korbecki
- Department of Molecular Biology, School of Medicine in Katowice, Medical University of Silesia, Medyków 18 St., 40-752, Katowice, Poland.
| | - Karolina Bajdak-Rusinek
- Department of Medical Genetics, School of Medicine in Katowice, Medical University of Silesia, Medyków 18 St., 40-752, Katowice, Poland
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Lefort B, Gouache E, Acquaviva C, Tardieu M, Benoist JF, Dumas JF, Servais S, Chevalier S, Vianey-Saban C, Labarthe F. Pharmacological inhibition of carnitine palmitoyltransferase 1 restores mitochondrial oxidative phosphorylation in human trifunctional protein deficient fibroblasts. Biochim Biophys Acta Mol Basis Dis 2017; 1863:1292-1299. [PMID: 28392417 DOI: 10.1016/j.bbadis.2017.04.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 03/20/2017] [Accepted: 04/05/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND Mitochondrial Trifunctional Protein deficiency (TFPD) is a severe genetic disease characterized by altered energy metabolism and accumulation of long-chain (LC) acylcarnitines in blood and tissues. This accumulation could impair the mitochondrial oxidative phosphorylation (OxPhos), contributing to the non-optimal outcome despite conventional diet therapy with medium-chain triglycerides (MCT). METHOD Acylcarnitine and OxPhos parameters were measured in TFPD-fibroblasts obtained from 8 children and cultured in medium mimicking fasting (LCFA) or conventional treatment (MCT), with or without Etomoxir (ETX) an inhibitor of carnitine palmitoyltransferase 1 (CPT1) activity, and were compared to results obtained with fibroblasts from 5 healthy-control children. The effects of various acylcarnitines were also tested on control fibroblasts. RESULTS In the LCFA-condition, TFPD-fibroblasts demonstrated a large accumulation of LC-acylcarnitines associated with decreased O2-consumption (63±3% of control, P<0.001) and ATP production (67±5%, P<0.001) without modification of coupling efficiency. A dose-dependent decrease in O2-consumption was reproduced in control fibroblasts by addition of increasing dose of LC-acylcarnitines, while it was almost preserved with MC-acylcarnitines. The MCT-condition reduced LC-acylcarnitine accumulation and partially improved O2-consumption (80±3%, P<0.01) in TFPD-fibroblasts. The addition of ETX in both LCFA- and MCT-conditions normalized acylcarnitine profiles and restored O2-consumption and ATP production at the same levels than control. CONCLUSION Accumulation of LC-acylcarnitines plays a major role in the pathophysiology of TFPD, reducing OxPhos capacities. These deleterious effects could be partially prevented by MCT-therapy and totally corrected by ETX. Inhibition of CPT1 may be view as a new therapeutic target for patients with a severe form of TFPD.
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Affiliation(s)
- Bruno Lefort
- CHU de Tours, Médecine Pédiatrique, Tours, France, and INSERM U1069, Université François Rabelais, Tours, France.
| | - Elodie Gouache
- CHU de Tours, Médecine Pédiatrique, Tours, France, and INSERM U1069, Université François Rabelais, Tours, France
| | | | - Marine Tardieu
- CHU de Tours, Médecine Pédiatrique, Tours, France, and INSERM U1069, Université François Rabelais, Tours, France
| | | | | | | | | | | | - François Labarthe
- CHU de Tours, Médecine Pédiatrique, Tours, France, and Inserm U1069, Université François Rabelais de Tours, PRES Centre-Val de Loire Universités, Tours, France
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Lemieux H, Boemer F, van Galen G, Serteyn D, Amory H, Baise E, Cassart D, van Loon G, Marcillaud-Pitel C, Votion DM. Mitochondrial function is altered in horse atypical myopathy. Mitochondrion 2016; 30:35-41. [PMID: 27374763 DOI: 10.1016/j.mito.2016.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 05/30/2016] [Accepted: 06/28/2016] [Indexed: 12/31/2022]
Abstract
Equine atypical myopathy in Europe is a fatal rhabdomyolysis syndrome that results from the ingestion of hypoglycin A contained in seeds and seedlings of Acer pseudoplatanus (sycamore maple). Acylcarnitine concentrations in serum and muscle OXPHOS capacity were determined in 15 atypical myopathy cases. All but one acylcarnitine were out of reference range and mitochondrial respiratory capacity was severely decreased up to 49% as compared to 10 healthy controls. The hallmark of atypical myopathy thus consists of a severe alteration in the energy metabolism including a severe impairment in muscle mitochondrial respiration that could contribute to its high death rate.
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Affiliation(s)
- Hélène Lemieux
- Faculty Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - François Boemer
- Biochemical Genetics Laboratory, Human Genetics, CHU Liege, University of Liege, Belgium
| | - Gaby van Galen
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Didier Serteyn
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium; Centre of Oxygen, Research and Development, University of Liege, Liege, Belgium
| | - Hélène Amory
- (c)Equine Clinic, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Etienne Baise
- (e)Department of Animal Productions: Biostatistics, Economy and Animal Selection, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | - Dominique Cassart
- Department of Pathology, Fundamental and Applied Research for Animals & Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium
| | | | | | - Dominique-M Votion
- (i)Equine Pole, Fundamental and Applied Research for Animals and Health (FARAH), Faculty of Veterinary Medicine, University of Liege, Belgium.
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Houten SM, Violante S, Ventura FV, Wanders RJA. The Biochemistry and Physiology of Mitochondrial Fatty Acid β-Oxidation and Its Genetic Disorders. Annu Rev Physiol 2015; 78:23-44. [PMID: 26474213 DOI: 10.1146/annurev-physiol-021115-105045] [Citation(s) in RCA: 438] [Impact Index Per Article: 48.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mitochondrial fatty acid β-oxidation (FAO) is the major pathway for the degradation of fatty acids and is essential for maintaining energy homeostasis in the human body. Fatty acids are a crucial energy source in the postabsorptive and fasted states when glucose supply is limiting. But even when glucose is abundantly available, FAO is a main energy source for the heart, skeletal muscle, and kidney. A series of enzymes, transporters, and other facilitating proteins are involved in FAO. Recessively inherited defects are known for most of the genes encoding these proteins. The clinical presentation of these disorders may include hypoketotic hypoglycemia, (cardio)myopathy, arrhythmia, and rhabdomyolysis and illustrates the importance of FAO during fasting and in hepatic and (cardio)muscular function. In this review, we present the current state of knowledge on the biochemistry and physiological functions of FAO and discuss the pathophysiological processes associated with FAO disorders.
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Affiliation(s)
- Sander M Houten
- Department of Genetics and Genomic Sciences and Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; ,
| | - Sara Violante
- Department of Genetics and Genomic Sciences and Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; ,
| | - Fatima V Ventura
- Metabolism and Genetics Group, Research Institute for Medicines and Pharmaceutical Sciences, iMed.ULisboa, 1649-003 Lisboa, Portugal; .,Department of Biochemistry and Human Biology, Faculty of Pharmacy, University of Lisbon, 1649-003 Lisboa, Portugal
| | - Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, University of Amsterdam, 1100 DE Amsterdam, The Netherlands; .,Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
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Kooijman S, van den Berg R, Ramkisoensing A, Boon MR, Kuipers EN, Loef M, Zonneveld TC, Lucassen EA, Sips HC, Chatzispyrou IA, Houtkooper RH, Meijer JH, Coomans CP, Biermasz NR, Rensen PC. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity. Proc Natl Acad Sci U S A 2015; 112:6748-53. [PMID: 25964318 DOI: 10.1073/pnas.1504239112] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity.
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Haack TB, Jackson CB, Murayama K, Kremer LS, Schaller A, Kotzaeridou U, de Vries MC, Schottmann G, Santra S, Büchner B, Wieland T, Graf E, Freisinger P, Eggimann S, Ohtake A, Okazaki Y, Kohda M, Kishita Y, Tokuzawa Y, Sauer S, Memari Y, Kolb-Kokocinski A, Durbin R, Hasselmann O, Cremer K, Albrecht B, Wieczorek D, Engels H, Hahn D, Zink AM, Alston CL, Taylor RW, Rodenburg RJ, Trollmann R, Sperl W, Strom TM, Hoffmann GF, Mayr JA, Meitinger T, Bolognini R, Schuelke M, Nuoffer JM, Kölker S, Prokisch H, Klopstock T. Deficiency of ECHS1 causes mitochondrial encephalopathy with cardiac involvement. Ann Clin Transl Neurol 2015; 2:492-509. [PMID: 26000322 PMCID: PMC4435704 DOI: 10.1002/acn3.189] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 02/03/2015] [Indexed: 01/01/2023] Open
Abstract
Objective Short-chain enoyl-CoA hydratase (ECHS1) is a multifunctional mitochondrial matrix enzyme that is involved in the oxidation of fatty acids and essential amino acids such as valine. Here, we describe the broad phenotypic spectrum and pathobiochemistry of individuals with autosomal-recessive ECHS1 deficiency. Methods Using exome sequencing, we identified ten unrelated individuals carrying compound heterozygous or homozygous mutations in ECHS1. Functional investigations in patient-derived fibroblast cell lines included immunoblotting, enzyme activity measurement, and a palmitate loading assay. Results Patients showed a heterogeneous phenotype with disease onset in the first year of life and course ranging from neonatal death to survival into adulthood. The most prominent clinical features were encephalopathy (10/10), deafness (9/9), epilepsy (6/9), optic atrophy (6/10), and cardiomyopathy (4/10). Serum lactate was elevated and brain magnetic resonance imaging showed white matter changes or a Leigh-like pattern resembling disorders of mitochondrial energy metabolism. Analysis of patients’ fibroblast cell lines (6/10) provided further evidence for the pathogenicity of the respective mutations by showing reduced ECHS1 protein levels and reduced 2-enoyl-CoA hydratase activity. While serum acylcarnitine profiles were largely normal, in vitro palmitate loading of patient fibroblasts revealed increased butyrylcarnitine, unmasking the functional defect in mitochondrial β-oxidation of short-chain fatty acids. Urinary excretion of 2-methyl-2,3-dihydroxybutyrate – a potential derivative of acryloyl-CoA in the valine catabolic pathway – was significantly increased, indicating impaired valine oxidation. Interpretation In conclusion, we define the phenotypic spectrum of a new syndrome caused by ECHS1 deficiency. We speculate that both the β-oxidation defect and the block in l-valine metabolism, with accumulation of toxic methacrylyl-CoA and acryloyl-CoA, contribute to the disorder that may be amenable to metabolic treatment approaches.
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Affiliation(s)
- Tobias B Haack
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - Christopher B Jackson
- Institute of Clinical Chemistry and University Children's Hospital, University of Bern 3010, Bern, Switzerland
| | - Kei Murayama
- Department of Metabolism, Chiba Children's Hospital Chiba, 266-0007, Japan
| | - Laura S Kremer
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - André Schaller
- Division of Human Genetics, Department of Pediatrics, University of Bern 3010, Bern, Switzerland
| | - Urania Kotzaeridou
- Divisions of Inherited Metabolic Disease and Neuropediatrics, Department of General Pediatrics, University Hospital Heidelberg D-69120, Heidelberg, Germany
| | - Maaike C de Vries
- Department of Pediatrics, Nijmegen Center for Mitochondrial Disorders, Radboud University Center 6525 GA, Nijmegen, The Netherlands
| | - Gudrun Schottmann
- Department of Neuropediatrics and NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin 13353, Berlin, Germany
| | - Saikat Santra
- Department of Pediatrics, Birmingham Children's Hospital Birmingham, B4 6NH, United Kingdom
| | - Boriana Büchner
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University 80336, Munich, Germany
| | - Thomas Wieland
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - Elisabeth Graf
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - Peter Freisinger
- Department of Pediatrics, Klinikum Reutlingen 72764, Reutlingen, Germany
| | - Sandra Eggimann
- Institute of Clinical Chemistry and University Children's Hospital, University of Bern 3010, Bern, Switzerland
| | - Akira Ohtake
- Department of Pediatrics, Faculty of Medicine, Saitama Medical University Saitama, 350-0495, Japan
| | - Yasushi Okazaki
- Division of Translational Research, Research Center for Genomic Medicine, Saitama Medical University Saitama, 350-1241, Japan ; Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University Saitama, 350-1241, Japan
| | - Masakazu Kohda
- Division of Translational Research, Research Center for Genomic Medicine, Saitama Medical University Saitama, 350-1241, Japan
| | - Yoshihito Kishita
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University Saitama, 350-1241, Japan
| | - Yoshimi Tokuzawa
- Division of Functional Genomics & Systems Medicine, Research Center for Genomic Medicine, Saitama Medical University Saitama, 350-1241, Japan
| | - Sascha Sauer
- Max-Planck-Institute for Molecular Genetics, Otto-Warburg Laboratory 14195, Berlin, Germany
| | - Yasin Memari
- Wellcome Trust Sanger Institute Hinxton, Cambridge, CB10 1SA, United Kingdom
| | | | - Richard Durbin
- Wellcome Trust Sanger Institute Hinxton, Cambridge, CB10 1SA, United Kingdom
| | - Oswald Hasselmann
- Department of Neuropediatrics, Children's Hospital of Eastern Switzerland St.Gallen 9006, St. Gallen, Switzerland
| | - Kirsten Cremer
- Institute of Human Genetics, University of Bonn 53127, Bonn, Germany
| | - Beate Albrecht
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen 45122, Essen, Germany
| | - Dagmar Wieczorek
- Institut für Humangenetik, Universitätsklinikum Essen, Universität Duisburg-Essen 45122, Essen, Germany
| | - Hartmut Engels
- Institute of Human Genetics, University of Bonn 53127, Bonn, Germany
| | - Dagmar Hahn
- Institute of Clinical Chemistry and University Children's Hospital, University of Bern 3010, Bern, Switzerland
| | - Alexander M Zink
- Institute of Human Genetics, University of Bonn 53127, Bonn, Germany
| | - Charlotte L Alston
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Robert W Taylor
- Wellcome Trust Centre for Mitochondrial Research, Institute of Neuroscience, The Medical School, Newcastle University Newcastle upon Tyne, NE2 4HH, United Kingdom
| | - Richard J Rodenburg
- Department of Pediatrics, Nijmegen Center for Mitochondrial Disorders, Radboud University Center 6525 GA, Nijmegen, The Netherlands
| | - Regina Trollmann
- Department of Pediatrics, Friedrich-Alexander-University of Erlangen-Nürnberg 91054, Erlangen, Germany
| | - Wolfgang Sperl
- Department of Pediatrics, Paracelsus Medical University Salzburg 5020, Salzburg, Austria
| | - Tim M Strom
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - Georg F Hoffmann
- Divisions of Inherited Metabolic Disease and Neuropediatrics, Department of General Pediatrics, University Hospital Heidelberg D-69120, Heidelberg, Germany
| | - Johannes A Mayr
- Department of Pediatrics, Paracelsus Medical University Salzburg 5020, Salzburg, Austria
| | - Thomas Meitinger
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany ; Munich Cluster for Systems Neurology (SyNergy) 80336, Munich, Germany ; DZNE - German Center for Neurodegenerative Diseases 80336, Munich, Germany
| | - Ramona Bolognini
- Division of Human Genetics, Department of Pediatrics, University of Bern 3010, Bern, Switzerland
| | - Markus Schuelke
- Department of Neuropediatrics and NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin 13353, Berlin, Germany
| | - Jean-Marc Nuoffer
- Institute of Clinical Chemistry and University Children's Hospital, University of Bern 3010, Bern, Switzerland
| | - Stefan Kölker
- Divisions of Inherited Metabolic Disease and Neuropediatrics, Department of General Pediatrics, University Hospital Heidelberg D-69120, Heidelberg, Germany
| | - Holger Prokisch
- Institute of Human Genetics, Technische Universität München 81675, Munich, Germany ; Institute of Human Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health 85764, Neuherberg, Germany
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University 80336, Munich, Germany ; Munich Cluster for Systems Neurology (SyNergy) 80336, Munich, Germany ; DZNE - German Center for Neurodegenerative Diseases 80336, Munich, Germany
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10
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Touw CML, Derks TGJ, Bakker BM, Groen AK, Smit GPA, Reijngoud DJ. From genome to phenome-Simple inborn errors of metabolism as complex traits. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2021-2029. [PMID: 24905735 DOI: 10.1016/j.bbadis.2014.05.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 04/30/2014] [Accepted: 05/28/2014] [Indexed: 01/05/2023]
Abstract
Sporadically, patients with a proven defect in either mFAO or OXPHOS are described presenting with a metabolic profile and clinical phenotype expressing concurrent defects in both pathways. Biochemical linkages between both processes are tight. Therefore, it is striking that concurrent dysfunction of both systems occurs so infrequent. In this review, the linkages between OXPHOS and mFAO and the hypothesized processes responsible for concurrent problems in both systems are reviewed, both from the point of view of primary biochemical connections and secondary cellular responses, i.e. signaling pathways constituting nutrient-sensing networks. We propose that affected signaling pathways may play an important role in the phenomenon of concurrent defects. Recent data indicate that interference in the affected signaling pathways may resolve the pathological phenotype even though the primary enzyme deficiency persists. This offers new (unexpected) prospects for treatment of these inborn errors of metabolism. This article is part of a Special Issue entitled: From Genome to Function.
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Affiliation(s)
- C M L Touw
- Section of Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands; Research Laboratory of Paediatrics, Beatrix Children's Hospital, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands.
| | - T G J Derks
- Section of Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands
| | - B M Bakker
- Research Laboratory of Paediatrics, Beatrix Children's Hospital, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands
| | - A K Groen
- Research Laboratory of Paediatrics, Beatrix Children's Hospital, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands
| | - G P A Smit
- Section of Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands
| | - D J Reijngoud
- Research Laboratory of Paediatrics, Beatrix Children's Hospital, University Medical Centre of Groningen, Groningen, The Netherlands; Center for Liver, Digestive and Metabolic Diseases, University Medical Centre of Groningen, Groningen, The Netherlands; Laboratory of Metabolic Diseases, Department of Laboratory Medicine, University of Groningen, University Medical Centre of Groningen, Groningen, The Netherlands
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11
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Wijnen WJ, van der Made I, van den Oever S, Hiller M, de Boer BA, Picavet DI, Chatzispyrou IA, Houtkooper RH, Tijsen AJ, Hagoort J, van Veen H, Everts V, Ruijter JM, Pinto YM, Creemers EE. Cardiomyocyte-specific miRNA-30c over-expression causes dilated cardiomyopathy. PLoS One 2014; 9:e96290. [PMID: 24789369 PMCID: PMC4008570 DOI: 10.1371/journal.pone.0096290] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 04/07/2014] [Indexed: 11/19/2022] Open
Abstract
MicroRNAs (miRNAs) regulate many aspects of cellular function and their deregulation has been implicated in heart disease. MiRNA-30c is differentially expressed in the heart during the progression towards heart failure and in vitro studies hint to its importance in cellular physiology. As little is known about the in vivo function of miRNA-30c in the heart, we generated transgenic mice that specifically overexpress miRNA-30c in cardiomyocytes. We show that these mice display no abnormalities until about 6 weeks of age, but subsequently develop a severely dilated cardiomyopathy. Gene expression analysis of the miRNA-30c transgenic hearts before onset of the phenotype indicated disturbed mitochondrial function. This was further evident by the downregulation of mitochondrial oxidative phosphorylation (OXPHOS) complexes III and IV at the protein level. Taken together these data indicate impaired mitochondrial function due to OXPHOS protein depletion as a potential cause for the observed dilated cardiomyopathic phenotype in miRNA-30c transgenic mice. We thus establish an in vivo role for miRNA-30c in cardiac physiology, particularly in mitochondrial function.
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Affiliation(s)
- Wino J. Wijnen
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
- Interuniversitair Cardiologisch Instituut Nederland (ICIN-NHI), Utrecht, The Netherlands
| | | | | | - Monika Hiller
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Bouke A. de Boer
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Daisy I. Picavet
- Department of Cell Biology and Histology, Leeuwenhoek Center of Advanced Microscopy (LCAM), Academic Medical Center, Amsterdam, The Netherlands
| | - Iliana A. Chatzispyrou
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, The Netherlands
| | - Riekelt H. Houtkooper
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, Amsterdam, The Netherlands
| | - Anke J. Tijsen
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Jaco Hagoort
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Henk van Veen
- Department of Cell Biology and Histology, Leeuwenhoek Center of Advanced Microscopy (LCAM), Academic Medical Center, Amsterdam, The Netherlands
| | - Vincent Everts
- Department of Cell Biology and Histology, Leeuwenhoek Center of Advanced Microscopy (LCAM), Academic Medical Center, Amsterdam, The Netherlands
| | - Jan M. Ruijter
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Yigal M. Pinto
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
| | - Esther E. Creemers
- Heart Failure Research Center, Academic Medical Center, Amsterdam, The Netherlands
- * E-mail:
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12
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Diekman EF, van der Pol WL, Nievelstein RAJ, Houten SM, Wijburg FA, Visser G. Muscle MRI in patients with long-chain fatty acid oxidation disorders. J Inherit Metab Dis 2014; 37:405-13. [PMID: 24305961 DOI: 10.1007/s10545-013-9666-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 11/12/2013] [Accepted: 11/20/2013] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Muscle magnetic resonance imaging (MRI) is a useful tool for visualizing abnormalities in neuromuscular disorders. The value of muscle MRI has not been studied in long-chain fatty acid oxidation (lcFAO) disorders. LcFAO disorders may present with metabolic myopathy including episodic rhabdomyolysis. OBJECTIVE To investigate whether lcFAO disorders are associated with muscle MRI abnormalities. METHODS Lower body MRI was performed in 20 patients with lcFAO disorders, i.e. three carnitine palmitoyltransferase 2 deficiency (CPT2D), 12 very long-chain acyl-CoA dehydrogenase deficiency (VLCADD), three mitochondrial trifunctional protein deficiency (MTPD) and two isolated long-chain hydroxyacyl-CoA dehydrogenase deficiency (LCHADD). RESULTS At the time of MRI, four patients had muscle weakness, 14 had muscle pain and 13 were exercise intolerant. Median creatine kinase (CK) level of patients at the day of MRI was 398 U/L (range 35-12,483). T1W and STIR signal intensity (SI) were markedly increased in MTPD patients from girdle to lower leg. VLCADD patients showed predominantly proximal T1W SI changes, whereas LCHADD patients mostly showed distal T1W SI changes. Prominent STIR weighted signal intensity increases of almost all muscle groups were observed in patients with VLCADD and LCHADD with very high CK (>11.000) levels. CONCLUSIONS AND RELEVANCE lcFAO disorders are associated with specific patterns of increased T1W and STIR signal intensity. These patterns may reflect lipid accumulation and inflammation secondary to lcFAO defects and progressive muscle damage. Future studies are needed to investigate whether muscle MRI might be a useful tool to monitor disease course and to study pathogenesis of lcFAO related myopathy.
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Affiliation(s)
- Eugene F Diekman
- Department of Paediatric Gastroenterology and Metabolic Diseases, Wilhelmina Children's Hospital, UMC Utrecht, KC 03.063.0, Lundlaan 6, 3584 EA, Utrecht, The Netherlands
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13
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Cooper AN, Brown JCL, Staples JF. Are long chain acyl CoAs responsible for suppression of mitochondrial metabolism in hibernating 13-lined ground squirrels? Comp Biochem Physiol B Biochem Mol Biol 2014; 170:50-7. [PMID: 24561259 DOI: 10.1016/j.cbpb.2014.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 02/11/2014] [Accepted: 02/13/2014] [Indexed: 11/18/2022]
Abstract
Hibernation in 13-lined ground squirrels (Ictidomys tridecemlineatus) is associated with a substantial suppression of whole-animal metabolism. We compared the metabolism of liver mitochondria isolated from torpid ground squirrels with those from interbout euthermic (IBE; recently aroused from torpor) and summer euthermic conspecifics. Succinate-fuelled state 3 respiration, calculated relative to mitochondrial protein, was suppressed in torpor by 48% and 44% compared with IBE and summer, respectively. This suppression remains when respiration is expressed relative to cytochrome c oxidase activity. We hypothesized that this suppression was caused by inhibition of succinate transport at the dicarboxylate transporter (DCT) by long-chain fatty acyl CoAs that may accumulate during torpor. We predicted, therefore, that exogenous palmitoyl CoA would inhibit respiration in IBE more than in torpor. Palmitoyl CoA inhibited respiration ~70%, in both torpor and IBE. The addition of carnitine, predicted to reverse palmitoyl CoA suppression by facilitating its transport into the mitochondrial matrix, did not rescue the respiration rates in IBE or torpor. Liver mitochondrial activities of carnitine palmitoyl transferase did not differ among IBE, torpor and summer animals. Although palmitoyl CoA inhibits succinate-fuelled respiration, this suppression is likely not related exclusively to inhibition of the DCT, and may involve additional mitochondrial transporters such as the adenine-nucleotide transporter.
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Affiliation(s)
- Alex N Cooper
- Department of Biology, University of Western Ontario, London, ON N6A5B8, Canada
| | - Jason C L Brown
- Department of Biology, University of Western Ontario, London, ON N6A5B8, Canada
| | - James F Staples
- Department of Biology, University of Western Ontario, London, ON N6A5B8, Canada.
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14
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Abstract
The mitochondrion relies on compartmentalization of certain enzymes, ions and metabolites for the sake of efficient metabolism. In order to fulfil its activities, a myriad of carriers are properly expressed, targeted and folded in the inner mitochondrial membrane. Among these carriers, the six-transmembrane-helix mitochondrial SLC25 (solute carrier family 25) proteins facilitate transport of solutes with disparate chemical identities across the inner mitochondrial membrane. Although their proper function replenishes building blocks needed for metabolic reactions, dysfunctional SLC25 proteins are involved in pathological states. It is the purpose of the present review to cover the current knowledge on the role of SLC25 transporters in health and disease.
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15
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Abstract
Fatty acids are a major fuel for the body and fatty acid oxidation is particularly important during fasting, sustained aerobic exercise and stress. The myocardium and resting skeletal muscle utilise long-chain fatty acids as a major source of energy. Inherited disorders affecting fatty acid oxidation seriously compromise the function of muscle and other highly energy-dependent tissues such as brain, nerve, heart, kidney and liver. Such defects encompass a wide spectrum of clinical disease, presenting in the neonatal period or infancy with recurrent hypoketotic hypoglycaemic encephalopathy, liver dysfunction, hyperammonaemia and often cardiac dysfunction. In older children, adolescence or adults there is often exercise intolerance with episodic myalgia or rhabdomyolysis in association with prolonged aerobic exercise or other exacerbating factors. Some disorders are particularly associated with toxic metabolites that may contribute to encephalopathy, polyneuropathy, axonopathy and pigmentary retinopathy. The phenotypic diversity encountered in defects of fat oxidation is partly explained by genotype/phenotype correlation and certain identifiable environmental factors but there remain many unresolved questions regarding the complex interaction of genetic, epigenetic and environmental influences that dictate phenotypic expression. It is becoming increasingly clear that the view that most inherited disorders are purely monogenic diseases is a naive concept. In the future our approach to understanding the phenotypic diversity and management of patients will be more realistically achieved from a polygenic perspective.
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Affiliation(s)
- Simon E Olpin
- Department of Clinical Chemistry, Sheffield Children's Hospital, Sheffield S10 2TH, UK.
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16
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Abstract
Mammalian hibernation involves periods of substantial suppression of metabolic rate (torpor) allowing energy conservation during winter. In thirteen-lined ground squirrels (Ictidomys tridecemlineatus), suppression of liver mitochondrial respiration during entrance into torpor occurs rapidly (within 2 h) before core body temperature falls below 30°C, whereas reversal of this suppression occurs slowly during arousal from torpor. We hypothesized that this pattern of rapid suppression in entrance and slow reversal during arousal was related to changes in the phosphorylation state of mitochondrial enzymes during torpor catalyzed by temperature-dependent kinases and phosphatases. We compared mitochondrial protein phosphorylation among hibernation metabolic states using immunoblot analyses and assessed how phosphorylation related to mitochondrial respiration rates. No proteins showed torpor-specific changes in phosphorylation, nor did phosphorylation state correlate with mitochondrial respiration. However, several proteins showed seasonal (summer vs. winter) differences in phosphorylation of threonine or serine residues. Using matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry, we identified three of these proteins: F1-ATPase α-chain, long chain-specific acyl-CoA dehydrogenase, and ornithine transcarbamylase. Therefore, we conclude that protein phosphorylation is likely a mechanism involved in bringing about seasonal changes in mitochondrial metabolism in hibernating ground squirrels, but it seems unlikely to play any role in acute suppression of mitochondrial metabolism during torpor.
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Affiliation(s)
- Dillon J Chung
- Department of Biology, University of Western Ontario, London, Ontario, Canada.
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17
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Violante S, IJlst L, Brinke HT, Almeida IT, Wanders RJA, Ventura FV, Houten SM. Carnitine palmitoyltransferase 2 and carnitine/acylcarnitine translocase are involved in the mitochondrial synthesis and export of acylcarnitines. FASEB J 2013; 27:2039-44. [DOI: 10.1096/fj.12-216689] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Sara Violante
- Metabolism and Genetics GroupResearch Institute for Medicines and Pharmaceutical Sciences (iMed.UL)Faculdade de FarmáciaUniversidade de LisboaLisbonPortugal
- Laboratory Genetic Metabolic Diseases, Department Clinical Chemistry and PediatricsUniversity of AmsterdamAmsterdamThe Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Department Clinical Chemistry and PediatricsUniversity of AmsterdamAmsterdamThe Netherlands
| | - Heleen te Brinke
- Laboratory Genetic Metabolic Diseases, Department Clinical Chemistry and PediatricsUniversity of AmsterdamAmsterdamThe Netherlands
| | - Isabel Tavares Almeida
- Metabolism and Genetics GroupResearch Institute for Medicines and Pharmaceutical Sciences (iMed.UL)Faculdade de FarmáciaUniversidade de LisboaLisbonPortugal
| | - Ronald J. A. Wanders
- Laboratory Genetic Metabolic Diseases, Department Clinical Chemistry and PediatricsUniversity of AmsterdamAmsterdamThe Netherlands
| | - Fátima V. Ventura
- Metabolism and Genetics GroupResearch Institute for Medicines and Pharmaceutical Sciences (iMed.UL)Faculdade de FarmáciaUniversidade de LisboaLisbonPortugal
| | - Sander M. Houten
- Laboratory Genetic Metabolic Diseases, Department Clinical Chemistry and PediatricsUniversity of AmsterdamAmsterdamThe Netherlands
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18
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Tonin AM, Amaral AU, Busanello ENB, Grings M, Castilho RF, Wajner M. Long-chain 3-hydroxy fatty acids accumulating in long-chain 3-hydroxyacyl-CoA dehydrogenase and mitochondrial trifunctional protein deficiencies uncouple oxidative phosphorylation in heart mitochondria. J Bioenerg Biomembr 2012; 45:47-57. [PMID: 23065309 DOI: 10.1007/s10863-012-9481-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/02/2012] [Indexed: 11/30/2022]
Abstract
Cardiomyopathy is a common clinical feature of some inherited disorders of mitochondrial fatty acid β-oxidation including mitochondrial trifunctional protein (MTP) and isolated long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiencies. Since individuals affected by these disorders present tissue accumulation of various fatty acids, including long-chain 3-hydroxy fatty acids, in the present study we investigated the effect of 3-hydroxydecanoic (3 HDCA), 3-hydroxydodecanoic (3 HDDA), 3-hydroxytetradecanoic (3 HTA) and 3-hydroxypalmitic (3 HPA) acids on mitochondrial oxidative metabolism, estimated by oximetry, NAD(P)H content, hydrogen peroxide production, membrane potential (ΔΨ) and swelling in rat heart mitochondrial preparations. We observed that 3 HTA and 3 HPA increased resting respiration and diminished the respiratory control and ADP/O ratios using glutamate/malate or succinate as substrates. Furthermore, 3 HDDA, 3 HTA and 3 HPA decreased ΔΨ, the matrix NAD(P)H pool and hydrogen peroxide production. These data indicate that these fatty acids behave as uncouplers of oxidative phosphorylation. We also verified that 3 HTA-induced uncoupling-effect was not mediated by the adenine nucleotide translocator and that this fatty acid induced the mitochondrial permeability transition pore opening in calcium-loaded organelles since cyclosporin A prevented the reduction of mitochondrial ΔΨ and swelling provoked by 3 HTA. The present data indicate that major 3-hydroxylated fatty acids accumulating in MTP and LCHAD deficiencies behave as strong uncouplers of oxidative phosphorylation potentially impairing heart energy homeostasis.
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Affiliation(s)
- Anelise M Tonin
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003 Porto Alegre, RS, Brazil
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19
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Farhoud MH, Nijtmans LG, Wanders RJA, Wessels HJCT, Lasonder E, Janssen AJM, Rodenburg RRJ, van den Heuvel LP, Smeitink JAM. Impaired ubiquitin-proteasome-mediated PGC-1α protein turnover and induced mitochondrial biogenesis secondary to complex-I deficiency. Proteomics 2012; 12:1349-62. [DOI: 10.1002/pmic.201100326] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Murtada H. Farhoud
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Leo G. Nijtmans
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Ronald J. A. Wanders
- Laboratory of Genetic Metabolic Diseases; Academic Medical Center at the University of Amsterdam; Meibergdreef Amsterdam The Netherlands
| | - Hans J. C. T. Wessels
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Edwin Lasonder
- Center for Molecular and Biomolecular Informatics; Nijmegen Center of Molecular Life Sciences, Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Antoon J. M. Janssen
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Richard R. J. Rodenburg
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Lambert P. van den Heuvel
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
| | - Jan A. M. Smeitink
- Nijmegen Center for Mitochondrial Disorders (NCMD); Radboud University Nijmegen Medical Centre; Nijmegen The Netherlands
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20
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Ralph SJ, Moreno-Sánchez R, Neuzil J, Rodríguez-Enríquez S. Inhibitors of succinate: quinone reductase/Complex II regulate production of mitochondrial reactive oxygen species and protect normal cells from ischemic damage but induce specific cancer cell death. Pharm Res 2011; 28:2695-730. [PMID: 21863476 DOI: 10.1007/s11095-011-0566-7] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 08/10/2011] [Indexed: 12/23/2022]
Abstract
Succinate:quinone reductase (SQR) of Complex II occupies a unique central point in the mitochondrial respiratory system as a major source of electrons driving reactive oxygen species (ROS) production. It is an ideal pharmaceutical target for modulating ROS levels in normal cells to prevent oxidative stress-induced damage or alternatively,increase ROS in cancer cells, inducing cell death.The value of drugs like diazoxide to prevent ROS production,protecting normal cells, whereas vitamin E analogues promote ROS in cancer cells to kill them is highlighted. As pharmaceuticals these agents may prevent degenerative disease and their modes of action are presently being fully explored. The evidence that SDH/Complex II is tightly coupled to the NADH/NAD+ ratio in all cells,impacted by the available supplies of Krebs cycle intermediates as essential NAD-linked substrates, and the NAD+-dependent regulation of SDH/Complex II are reviewed, as are links to the NAD+-dependent dehydrogenases, Complex I and the E3 dihiydrolipoamide dehydrogenase to produce ROS. This review collates and discusses diverse sources of information relating to ROS production in different biological systems, focussing on evidence for SQR as the main source of ROS production in mitochondria, particularly its relevance to protection from oxidative stress and to the mitochondrial-targeted anti cancer drugs (mitocans) as novel cancer therapies [corrected].
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Wang T, Si Y, Shirihai OS, Si H, Schultz V, Corkey RF, Hu L, Deeney JT, Guo W, Corkey BE. Respiration in adipocytes is inhibited by reactive oxygen species. Obesity (Silver Spring) 2010; 18:1493-502. [PMID: 20035277 PMCID: PMC6154476 DOI: 10.1038/oby.2009.456] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
It is a desirable goal to stimulate fuel oxidation in adipocytes and shift the balance toward less fuel storage and more burning. To understand this regulatory process, respiration was measured in primary rat adipocytes, mitochondria, and fat-fed mice. Maximum O(2) consumption, in vitro, was determined with a chemical uncoupler of oxidative phosphorylation (carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP)). The adenosine triphosphate/adenosine diphosphate (ATP/ADP) ratio was measured by luminescence. Mitochondria were localized by confocal microscopy with MitoTracker Green and their membrane potential (Delta psi(M)) measured using tetramethylrhodamine ethyl ester perchlorate (TMRE). The effect of N-acetylcysteine (NAC) on respiration and body composition in vivo was assessed in mice. Addition of FCCP collapsed Delta psi(M) and decreased the ATP/ADP ratio. However, we demonstrated the same rate of adipocyte O(2) consumption in the absence or presence of fuels and FCCP. Respiration was only stimulated when reactive oxygen species (ROS) were scavenged by pyruvate or NAC: other fuels or fuel combinations had little effect. Importantly, the ROS scavenging role of pyruvate was not affected by rotenone, an inhibitor of mitochondrial complex I. In addition, mice that consumed NAC exhibited increased O(2) consumption and decreased body fat in vivo. These studies suggest for the first time that adipocyte O(2) consumption may be inhibited by ROS, because pyruvate and NAC stimulated respiration. ROS inhibition of O(2) consumption may explain the difficulty to identify effective strategies to increase fat burning in adipocytes. Stimulating fuel oxidation in adipocytes by decreasing ROS may provide a novel means to shift the balance from fuel storage to fuel burning.
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Affiliation(s)
- Tong Wang
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Yaguang Si
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Orian S. Shirihai
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Huiqing Si
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Vera Schultz
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Richard F. Corkey
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Liping Hu
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Jude T. Deeney
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Wen Guo
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Barbara E. Corkey
- Obesity Research Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
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22
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Violante S, Ijlst L, van Lenthe H, de Almeida IT, Wanders RJ, Ventura FV. Carnitine palmitoyltransferase 2: New insights on the substrate specificity and implications for acylcarnitine profiling. Biochim Biophys Acta Mol Basis Dis 2010; 1802:728-32. [PMID: 20538056 DOI: 10.1016/j.bbadis.2010.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 05/31/2010] [Accepted: 06/01/2010] [Indexed: 12/30/2022]
Abstract
Over the last years acylcarnitines have emerged as important biomarkers for the diagnosis of mitochondrial fatty acid beta-oxidation (mFAO) and branched-chain amino acid oxidation disorders assuming they reflect the potentially toxic acyl-CoA species, accumulating intramitochondrially upstream of the enzyme block. However, the origin of these intermediates still remains poorly understood. A possibility exists that carnitine palmitoyltransferase 2 (CPT2), member of the carnitine shuttle, is involved in the intramitochondrial synthesis of acylcarnitines from accumulated acyl-CoA metabolites. To address this issue, the substrate specificity profile of CPT2 was herein investigated. Saccharomyces cerevisiae homogenates expressing human CPT2 were incubated with saturated and unsaturated C2-C26 acyl-CoAs and branched-chain amino acid oxidation intermediates. The produced acylcarnitines were quantified by ESI-MS/MS. We show that CPT2 is active with medium (C8-C12) and long-chain (C14-C18) acyl-CoA esters, whereas virtually no activity was found with short- and very long-chain acyl-CoAs or with branched-chain amino acid oxidation intermediates. Trans-2-enoyl-CoA intermediates were also found to be poor substrates for CPT2. Inhibition studies performed revealed that trans-2-C16:1-CoA may act as a competitive inhibitor of CPT2 (K(i) of 18.8 microM). The results obtained clearly demonstrate that CPT2 is able to reverse its physiological mechanism for medium and long-chain acyl-CoAs contributing to the abnormal acylcarnitines profiles characteristic of most mFAO disorders. The finding that trans-2-enoyl-CoAs are poorly handled by CPT2 may explain the absence of trans-2-enoyl-carnitines in the profiles of mitochondrial trifunctional protein deficient patients, the only defect where they accumulate, and the discrepancy between the clinical features of this and other long-chain mFAO disorders such as very long-chain acyl-CoA dehydrogenase deficiency.
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Affiliation(s)
- Sara Violante
- Metabolism and Genetics Group, Research Institute for Medicines and Pharmaceutical Sciences, iMed.UL, Faculdade de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
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Tonin AM, Ferreira GC, Grings M, Viegas CM, Busanello EN, Amaral AU, Zanatta A, Schuck PF, Wajner M. Disturbance of mitochondrial energy homeostasis caused by the metabolites accumulating in LCHAD and MTP deficiencies in rat brain. Life Sci 2010; 86:825-31. [PMID: 20399795 DOI: 10.1016/j.lfs.2010.04.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 03/31/2010] [Accepted: 04/02/2010] [Indexed: 12/31/2022]
Abstract
AIMS We investigated the in vitro effects of 3-hydroxydodecanoic (3HDA), 3-hydroxytetradecanoic (3HTA) and 3-hydroxypalmitic (3HPA) acids, which accumulate in tissues of patients affected by mitochondrial trifunctional protein (MTP) and isolated long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiencies, on various parameters of energy homeostasis in mitochondrial preparations from brain of young rats. MAIN METHODS We measured the respiratory parameters state 4, state 3, respiratory control ratio (RCR) and ADP/O ratio by the rate of oxygen consumption, as well as the mitochondrial membrane potential and the matrix NAD(P)H levels in the presence of the fatty acids. KEY FINDINGS We found that 3HDA, 3HTA and 3HPA markedly increased state 4 respiration and diminished the RCR using glutamate plus malate or succinate as substrates. 3HTA and 3HPA also diminished the mitochondrial membrane potential and the matrix NAD(P)H levels. In addition, 3HTA decreased state 3 respiration using glutamate/malate, but not pyruvate/malate or succinate as substrates. Our data indicate that the long-chain 3-hydroxy fatty acids that accumulate in LCHAD/MTP deficiencies act as uncouplers of oxidative phosphorylation, while 3HTA also behaves as a metabolic inhibitor. SIGNIFICANCE It is presumed that impairment of brain energy homeostasis caused by these endogenous accumulating compounds may contribute at least in part to the neuropathology of LCHAD/MTP deficiencies.
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Affiliation(s)
- Anelise M Tonin
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Ralph SJ, Rodríguez-enríquez S, Neuzil J, Moreno-sánchez R. Bioenergetic pathways in tumor mitochondria as targets for cancer therapy and the importance of the ROS-induced apoptotic trigger. Mol Aspects Med 2010; 31:29-59. [DOI: 10.1016/j.mam.2009.12.006] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Accepted: 12/11/2009] [Indexed: 12/22/2022]
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Sauer SW, Okun JG, Hoffmann GF, Koelker S, Morath MA. Impact of short- and medium-chain organic acids, acylcarnitines, and acyl-CoAs on mitochondrial energy metabolism. Biochim Biophys Acta 2008; 1777:1276-82. [PMID: 18582432 DOI: 10.1016/j.bbabio.2008.05.447] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2008] [Revised: 05/15/2008] [Accepted: 05/20/2008] [Indexed: 10/22/2022]
Abstract
Accumulation of organic acids as well as their CoA and carnitine esters in tissues and body fluids is a common finding in organic acidurias, beta-oxidation defects, Reye syndrome, and Jamaican vomiting sickness. Pathomechanistic approaches for these disorders have been often focused on the effect of accumulating organic acids on mitochondrial energy metabolism, whereas little is known about the pathophysiologic role of short- and medium-chain acyl-CoAs and acylcarnitines. Therefore, we investigated the impact of short- and medium-chain organic acids, acylcarnitines, and acyl-CoAs on central components of mitochondrial energy metabolism, namely alpha-ketoglutarate dehydrogenase complex, pyruvate dehydrogenase complex, and single enzyme complexes I-V of respiratory chain. Although at varying degree, all acyl-CoAs had an inhibitory effect on pyruvate dehydrogenase complex and alpha-ketoglutarate dehydrogenase complex activity. Effect sizes were critically dependent on chain length and number of functional groups. Unexpectedly, octanoyl-CoA was shown to inhibit complex III. The inhibition was noncompetitive regarding reduced ubiquinone and uncompetitive regarding cytochrome c. In addition, octanoyl-CoA caused a blue shift in the gamma band of the absorption spectrum of reduced complex III. This effect may play a role in the pathogenesis of medium-chain and multiple acyl-CoA dehydrogenase deficiency, Reye syndrome, and Jamaican vomiting sickness which are inherited and acquired conditions of intracellular accumulation of octanoyl-CoA.
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Affiliation(s)
- Sven Wolfgang Sauer
- Department of General Pediatrics, Division of Inborn Metabolic Diseases, University Children's Hospital, Heidelberg, Germany.
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Bortolami S, Comelato E, Zoccarato F, Alexandre A, Cavallini L. Long chain fatty acyl-CoA modulation of H(2)O (2) release at mitochondrial complex I. J Bioenerg Biomembr 2008; 40:9-18. [PMID: 18214656 DOI: 10.1007/s10863-008-9126-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
Abstract
Complex I is responsible for most of the mitochondrial H(2)O(2) release, low during the oxidation of the NAD linked substrates and high during succinate oxidation, via reverse electron flow. This H(2)O(2) production appear physiological since it occurs at submillimolar concentrations of succinate also in the presence of NAD substrates in heart (present work) and rat brain mitochondria (Zoccarato et al., Biochem J, 406:125-129, 2007). Long chain fatty acyl-CoAs, but not fatty acids, act as strong inhibitors of succinate dependent H(2)O(2) release. The inhibitory effect of acyl-CoAs is independent of their oxidation, being relieved by carnitine and unaffected or potentiated by malonyl-CoA. The inhibition appears to depend on the unbound form since the acyl-CoA effect decreases at BSA concentrations higher than 2 mg/ml; it is not dependent on DeltapH or Deltap and could depend on the inhibition of reverse electron transfer at complex I, since palmitoyl-CoA inhibits the succinate dependent NAD(P) or acetoacetate reduction.
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Ventura FV, Tavares de Almeida I, Wanders RJA. Inhibition of adenine nucleotide transport in rat liver mitochondria by long-chain acyl-coenzyme A beta-oxidation intermediates. Biochem Biophys Res Commun 2006; 352:873-8. [PMID: 17157818 DOI: 10.1016/j.bbrc.2006.11.109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2006] [Accepted: 11/17/2006] [Indexed: 11/17/2022]
Abstract
Long-chain acyl-coenzyme A esters (LCAC), which may accumulate under different pathological conditions and especially in patients with a mitochondrial fatty acid beta-oxidation defect, have long been known as potent inhibitors of several enzymes in multiple metabolic pathways, particularly the oxidative phosphorylation system (OXPHOS). To shed more light on the inhibitory mechanisms of acyl-CoA esters upon energy metabolism, the effect of palmitoyl-CoA and its beta-oxidation intermediates on OXPHOS was studied. We have recently shown that, using rat liver mitochondria, LCAC inhibit l-glutamate driven oxygen consumption in the presence of ADP whereas no effect is found when an uncoupler is used to stimulate respiration maximally. A similar inhibitory effect of these compounds is now reported upon the distribution of ATP for intra- and extra-mitochondrial utilization. Taken together these data strongly suggest that the inhibition of ADP-induced respiration with l-glutamate as substrate by LCAC is primarily due to inhibition of the mitochondrial ADP/ATP carrier.
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Affiliation(s)
- Fátima V Ventura
- Centro de Patogénese Molecular - Unidade de Biologia Molecular e Biopatologia Experimental, Faculdade de Farmácia, Universidade de Lisboa, Lisboa, Portugal.
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