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Gurney M, Cotter TG, Wittich CM. 28-Year-Old Woman With Malaise, Cough, Myalgia, and Dark Urine. Mayo Clin Proc 2017; 92:e1-e5. [PMID: 28062066 DOI: 10.1016/j.mayocp.2016.03.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 03/22/2016] [Accepted: 03/25/2016] [Indexed: 01/04/2023]
Affiliation(s)
- Mark Gurney
- Resident in Internal Medicine, Mayo School of Graduate Medical Education, Mayo Clinic, Rochester, MN
| | - Thomas G Cotter
- Resident in Internal Medicine, Mayo School of Graduate Medical Education, Mayo Clinic, Rochester, MN
| | - Christopher M Wittich
- Advisor to residents and Consultant in General Internal Medicine, Mayo Clinic, Rochester, MN.
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Yamada K, Kobayashi H, Bo R, Purevsuren J, Mushimoto Y, Takahashi T, Hasegawa Y, Taketani T, Fukuda S, Yamaguchi S. Efficacy of bezafibrate on fibroblasts of glutaric acidemia type II patients evaluated using an in vitro probe acylcarnitine assay. Brain Dev 2017; 39:48-57. [PMID: 27591119 DOI: 10.1016/j.braindev.2016.08.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Revised: 07/29/2016] [Accepted: 08/10/2016] [Indexed: 11/19/2022]
Abstract
INTRODUCTION We evaluated the effects of bezafibrate (BEZ) on β-oxidation in fibroblasts obtained from patients with glutaric acidemia type II (GA2) of various clinical severities using an in vitro probe (IVP) assay. METHODS Cultured fibroblasts from 12 patients with GA2, including cases of the neonatal-onset type both with and without congenital anomalies (the prenatal- and neonatal-onset forms, respectively), the infantile-onset, and the myopathic forms, were studied. The IVP assay was performed by measuring acylcarnitines (ACs) in the cell culture medium of fibroblasts incubated with palmitic acid for 96h in the presence of 0-800μM BEZ using tandem mass spectrometry. RESULTS The IVP assay showed that 100μM BEZ markedly reduced the level of palmitoylcarnitine (C16) in the neonatal-onset, infantile-onset, and myopathic forms of GA2, either increasing or maintaining a high level of acetylcarnitine (C2), which serves as an index of energy production via β-oxidation. In the prenatal-onset form, although a small reduction of C16 was also observed in the presence of 100μM BEZ, the level of C2 remained low. At concentrations higher than 100μM, BEZ further decreased the level of ACs including C16, but a concentration over 400μM decreased the level of C2 in most cases. DISCUSSION BEZ at 100μM was effective for all GA2 phenotypes except for the prenatal-onset form, as a reduction of C16 without deterioration of C2 is considered to indicate improvement of β-oxidation. The effects of higher doses BEZ could not be estimated by the IVP assay but might be small or nonexistent.
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Affiliation(s)
- Kenji Yamada
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan.
| | - Hironori Kobayashi
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Ryosuke Bo
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan; Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Jamiyan Purevsuren
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Yuichi Mushimoto
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Tomoo Takahashi
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Yuki Hasegawa
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Takeshi Taketani
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Seiji Fukuda
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
| | - Seiji Yamaguchi
- Department of Pediatrics, Shimane University, Faculty of Medicine, Izumo, Shimane, Japan
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53
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Vissing J. Exercise training in metabolic myopathies. Rev Neurol (Paris) 2016; 172:559-565. [DOI: 10.1016/j.neurol.2016.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 08/22/2016] [Accepted: 08/25/2016] [Indexed: 10/21/2022]
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Pena LDM, van Calcar SC, Hansen J, Edick MJ, Walsh Vockley C, Leslie N, Cameron C, Mohsen AW, Berry SA, Arnold GL, Vockley J. Outcomes and genotype-phenotype correlations in 52 individuals with VLCAD deficiency diagnosed by NBS and enrolled in the IBEM-IS database. Mol Genet Metab 2016; 118:272-81. [PMID: 27209629 PMCID: PMC4970910 DOI: 10.1016/j.ymgme.2016.05.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 12/21/2022]
Abstract
Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency can present at various ages from the neonatal period to adulthood, and poses the greatest risk of complications during intercurrent illness or after prolonged fasting. Early diagnosis, treatment, and surveillance can reduce mortality; hence, the disorder is included in the newborn Recommended Uniform Screening Panel (RUSP) in the United States. The Inborn Errors of Metabolism Information System (IBEM-IS) was established in 2007 to collect longitudinal information on individuals with inborn errors of metabolism included in newborn screening (NBS) programs, including VLCAD deficiency. We retrospectively analyzed early outcomes for individuals who were diagnosed with VLCAD deficiency by NBS and describe initial presentations, diagnosis, clinical outcomes and treatment in a cohort of 52 individuals ages 1-18years. Maternal prenatal symptoms were not reported, and most newborns remained asymptomatic. Cardiomyopathy was uncommon in the cohort, diagnosed in 2/52 cases. Elevations in creatine kinase were a common finding, and usually first occurred during the toddler period (1-3years of age). Diagnostic evaluations required several testing modalities, most commonly plasma acylcarnitine profiles and molecular testing. Functional testing, including fibroblast acylcarnitine profiling and white blood cell or fibroblast enzyme assay, is a useful diagnostic adjunct if uncharacterized mutations are identified.
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Affiliation(s)
| | | | | | | | | | - Nancy Leslie
- Cincinnati Children's Hospital Medical Center, USA
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55
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Altered Energetics of Exercise Explain Risk of Rhabdomyolysis in Very Long-Chain Acyl-CoA Dehydrogenase Deficiency. PLoS One 2016; 11:e0147818. [PMID: 26881790 PMCID: PMC4755596 DOI: 10.1371/journal.pone.0147818] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/09/2016] [Indexed: 12/31/2022] Open
Abstract
Rhabdomyolysis is common in very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) and other metabolic myopathies, but its pathogenic basis is poorly understood. Here, we show that prolonged bicycling exercise against a standardized moderate workload in VLCADD patients is associated with threefold bigger changes in phosphocreatine (PCr) and inorganic phosphate (Pi) concentrations in quadriceps muscle and twofold lower changes in plasma acetyl-carnitine levels than in healthy subjects. This result is consistent with the hypothesis that muscle ATP homeostasis during exercise is compromised in VLCADD. However, the measured rates of PCr and Pi recovery post-exercise showed that the mitochondrial capacity for ATP synthesis in VLCADD muscle was normal. Mathematical modeling of oxidative ATP metabolism in muscle composed of three different fiber types indicated that the observed altered energy balance during submaximal exercise in VLCADD patients may be explained by a slow-to-fast shift in quadriceps fiber-type composition corresponding to 30% of the slow-twitch fiber-type pool in healthy quadriceps muscle. This study demonstrates for the first time that quadriceps energy balance during exercise in VLCADD patients is altered but not because of failing mitochondrial function. Our findings provide new clues to understanding the risk of rhabdomyolysis following exercise in human VLCADD.
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56
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Shima A, Yasuno T, Yamada K, Yamaguchi M, Kohno R, Yamaguchi S, Kido H, Fukuda H. First Japanese Case of Carnitine Palmitoyltransferase II Deficiency with the Homozygous Point Mutation S113L. Intern Med 2016; 55:2659-61. [PMID: 27629963 DOI: 10.2169/internalmedicine.55.6288] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Carnitine palmitoyltransferase II (CPT II) deficiency is a rare inherited disorder related to recurrent episodes of rhabdomyolysis. The adult myopathic form of CPT II deficiency is relatively benign and difficult to diagnose. The point mutation S113L in CPT2 is very common in Caucasian patients, whereas F383Y is the most common mutation among Japanese patients. We herein present a case of CPT II deficiency in a Japanese patient homozygous for the missense mutation S113L. The patient showed a decreased frequency of rhabdomyolysis recurrence after the administration of a diet containing medium-chain triglyceride oil and supplementation with carnitine and bezafibrate.
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Affiliation(s)
- Atsushi Shima
- Department of Neurology, Saiseikai Noe Hospital, Japan
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57
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Mitochondrial dysfunction in fatty acid oxidation disorders: insights from human and animal studies. Biosci Rep 2015; 36:e00281. [PMID: 26589966 PMCID: PMC4718505 DOI: 10.1042/bsr20150240] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/20/2015] [Indexed: 12/17/2022] Open
Abstract
Patients affected by FAOD commonly present with hepatopathy, cardiomyopathy, skeletal myopathy and encephalopathy. Human and animal evidences indicate that mitochondrial functions are disrupted by fatty acids and derivatives accumulating in these disorders, suggesting that lipotoxicity may contribute to their pathogenesis. Mitochondrial fatty acid oxidation (FAO) plays a pivotal role in maintaining body energy homoeostasis mainly during catabolic states. Oxidation of fatty acids requires approximately 25 proteins. Inherited defects of FAO have been identified in the majority of these proteins and constitute an important group of inborn errors of metabolism. Affected patients usually present with severe hepatopathy, cardiomyopathy and skeletal myopathy, whereas some patients may suffer acute and/or progressive encephalopathy whose pathogenesis is poorly known. In recent years growing evidence has emerged indicating that energy deficiency/disruption of mitochondrial homoeostasis is involved in the pathophysiology of some fatty acid oxidation defects (FAOD), although the exact underlying mechanisms are not yet established. Characteristic fatty acids and carnitine derivatives are found at high concentrations in these patients and more markedly during episodes of metabolic decompensation that are associated with worsening of clinical symptoms. Therefore, it is conceivable that these compounds may be toxic. We will briefly summarize the current knowledge obtained from patients and genetic mouse models with these disorders indicating that disruption of mitochondrial energy, redox and calcium homoeostasis is involved in the pathophysiology of the tissue damage in the more common FAOD, including medium-chain acyl-CoA dehydrogenase (MCAD), long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) and very long-chain acyl-CoA dehydrogenase (VLCAD) deficiencies. We will also provide evidence that the fatty acids and derivatives that accumulate in these diseases disrupt mitochondrial homoeostasis. The elucidation of the toxic mechanisms of these compounds may offer new perspectives for potential novel adjuvant therapeutic strategies in selected disorders of this group.
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58
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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: 454] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [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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59
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Lund M, Olsen RKJ, Gregersen N. A short introduction to acyl-CoA dehydrogenases; deficiencies and novel treatment strategies. Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2015.1092869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Rahman S. Emerging aspects of treatment in mitochondrial disorders. J Inherit Metab Dis 2015; 38:641-53. [PMID: 25962587 DOI: 10.1007/s10545-015-9855-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/17/2015] [Accepted: 04/21/2015] [Indexed: 11/26/2022]
Abstract
Mitochondrial diseases are clinically, biochemically and genetically heterogeneous disorders of two genomes, for which effective curative therapies are currently lacking. With the exception of a few rare vitamin/cofactor responsive conditions (including ACAD9 deficiency, disorders of coenzyme Q(10) biosynthesis, and Leigh syndrome caused by mutations in the SLC19A3 transporter), the mainstay of treatment for the vast majority of patients involves supportive measures. The search for a cure for mitochondrial disease is the subject of intensive research efforts by many investigators across the globe, but the goal remains elusive. The clinical and genetic heterogeneity, multisystemic nature of many of these disorders, unpredictable natural course, relative inaccessibility of the mitochondrion and lack of validated, clinically meaningful outcome measures, have all presented great challenges to the design of rigorous clinical trials. This review discusses barriers to developing effective therapies for mitochondrial disease, models for evaluating the efficacy of novel treatments and summarises the most promising emerging therapies in six key areas: 1) antioxidant approaches; 2) stimulating mitochondrial biogenesis; 3) targeting mitochondrial membrane lipids, dynamics and mitophagy; 4) replacement therapy; 5) cell-based therapies; and 6) gene therapy approaches for both mtDNA and nuclear-encoded defects of mitochondrial metabolism.
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Affiliation(s)
- Shamima Rahman
- Mitochondrial Research Group, Genetics and Genomic Medicine, Institute of Child Health, University College London and Metabolic Unit, Great Ormond Street Hospital, 30 Guilford Street, London, WC1N 1EH, UK,
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61
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Olsen RKJ, Cornelius N, Gregersen N. Redox signalling and mitochondrial stress responses; lessons from inborn errors of metabolism. J Inherit Metab Dis 2015; 38:703-19. [PMID: 26025548 PMCID: PMC4493798 DOI: 10.1007/s10545-015-9861-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 04/25/2015] [Accepted: 05/07/2015] [Indexed: 12/14/2022]
Abstract
Mitochondria play a key role in overall cell physiology and health by integrating cellular metabolism with cellular defense and repair mechanisms in response to physiological or environmental changes or stresses. In fact, dysregulation of mitochondrial stress responses and its consequences in the form of oxidative stress, has been linked to a wide variety of diseases including inborn errors of metabolism. In this review we will summarize how the functional state of mitochondria -- and especially the concentration of reactive oxygen species (ROS), produced in connection with the respiratory chain -- regulates cellular stress responses by redox regulation of nuclear gene networks involved in repair systems to maintain cellular homeostasis and health. Based on our own and other's studies we re-introduce the ROS triangle model and discuss how inborn errors of mitochondrial metabolism, by production of pathological amounts of ROS, may cause disturbed redox signalling and induce chronic cell stress with non-resolving or compromised cell repair responses and increased susceptibility to cell stress induced cell death. We suggest that this model may have important implications for those inborn errors of metabolism, where mitochondrial dysfunction plays a major role, as it allows the explanation of oxidative stress, metabolic reprogramming and altered signalling growth pathways that have been reported in many of the diseases. It is our hope that the model may facilitate novel ideas and directions that can be tested experimentally and used in the design of future new approaches for pre-symptomatic diagnosis and prognosis and perhaps more effective treatments of inborn errors of metabolism.
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Affiliation(s)
- Rikke K J Olsen
- Research Unit for Molecular Medicine, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark,
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Bastin J, Bonnefont JP, Djouadi F, Bresson JL. Should the beneficial impact of bezafibrate on fatty acid oxidation disorders be questioned? J Inherit Metab Dis 2015; 38:371-2. [PMID: 25310995 DOI: 10.1007/s10545-014-9775-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 09/21/2014] [Indexed: 10/24/2022]
MESH Headings
- Acyl-CoA Dehydrogenase, Long-Chain/deficiency
- Acyl-CoA Dehydrogenase, Long-Chain/genetics
- Bezafibrate/adverse effects
- Bezafibrate/therapeutic use
- Carnitine O-Palmitoyltransferase/deficiency
- Carnitine O-Palmitoyltransferase/genetics
- Congenital Bone Marrow Failure Syndromes
- Fatty Acids/metabolism
- Heart Rate/drug effects
- Humans
- Lipid Metabolism, Inborn Errors/diagnosis
- Lipid Metabolism, Inborn Errors/drug therapy
- Lipid Metabolism, Inborn Errors/enzymology
- Lipid Metabolism, Inborn Errors/genetics
- Lipid Metabolism, Inborn Errors/physiopathology
- Lipolysis/drug effects
- Metabolism, Inborn Errors/diagnosis
- Metabolism, Inborn Errors/drug therapy
- Metabolism, Inborn Errors/enzymology
- Metabolism, Inborn Errors/genetics
- Metabolism, Inborn Errors/physiopathology
- Mitochondrial Diseases/diagnosis
- Mitochondrial Diseases/drug therapy
- Mitochondrial Diseases/enzymology
- Mitochondrial Diseases/genetics
- Mitochondrial Diseases/physiopathology
- Muscular Diseases/diagnosis
- Muscular Diseases/drug therapy
- Muscular Diseases/enzymology
- Muscular Diseases/genetics
- Muscular Diseases/physiopathology
- Oxidation-Reduction
- Treatment Outcome
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Affiliation(s)
- Jean Bastin
- INSERM UMR-S 1124, Université Paris Descartes, UFR Biomédicale des Saints-Pères 45, rue des Saints-Pères, 75270, Paris cedex 06, France,
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63
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Ørngreen MC, Vissing J, Laforét P. No effect of bezafibrate in patients with CPTII and VLCAD deficiencies. J Inherit Metab Dis 2015; 38:373-4. [PMID: 25331908 DOI: 10.1007/s10545-014-9779-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 10/02/2014] [Indexed: 10/24/2022]
Affiliation(s)
- Mette Cathrine Ørngreen
- Neuromuscular Clinic and Research Unit, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark,
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64
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Diekman EF, van Weeghel M, Wanders RJA, Visser G, Houten SM. Food withdrawal lowers energy expenditure and induces inactivity in long-chain fatty acid oxidation-deficient mouse models. FASEB J 2014; 28:2891-900. [PMID: 24648546 DOI: 10.1096/fj.14-250241] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is an inherited disorder of mitochondrial long-chain fatty acid β-oxidation (FAO). Patients with VLCAD deficiency may present with hypoglycemia, hepatomegaly, cardiomyopathy, and myopathy. Although several mouse models have been developed to aid in the study of the pathogenesis of long-chain FAO defects, the muscular phenotype is underexposed. To address the muscular phenotype, we used a newly developed mouse model on a mixed genetic background with a more severe defect in FAO (LCAD(-/-); VLCAD(+/-)) in addition to a validated mouse model (LCAD(-/-); VLCAD(+/+)) and compared them with wild-type (WT) mice. We found that both mouse models show a 20% reduction in energy expenditure (EE) and a 3-fold decrease in locomotor activity in the unfed state. In addition, we found a 1.7°C drop in body temperature in unfed LCAD(-/-); VLCAD(+/+) mice compared with WT body temperature. We conclude that food withdrawal-induced inactivity, hypothermia, and reduction in EE are novel phenotypes associated with FAO deficiency in mice. Unexpectedly, inactivity was not explained by rhabdomyolysis, but rather reflected the overall reduced capacity of these mice to generate heat. We suggest that mice are partly protected against the negative consequence of an FAO defect.-Diekman, E. F., van Weeghel, M., Wanders, R. J. A., Visser, G., Houten, S. M. Food withdrawal lowers energy expenditure and induces inactivity in long-chain fatty acid oxidation-deficient mouse models.
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Affiliation(s)
- Eugene F Diekman
- Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center (UMC) Utrecht, the Netherlands; Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, and
| | - Michel van Weeghel
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, and
| | - Ronald J A Wanders
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, and Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| | - Gepke Visser
- Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center (UMC) Utrecht, the Netherlands
| | - Sander M Houten
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, and Department of Pediatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and Department of Genetics and Genomic Sciences, Icahn Institute for Genomics and Multiscale Biology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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