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Babcock SJ, Houten SM, Gillingham MB. A review of fatty acid oxidation disorder mouse models. Mol Genet Metab 2024; 142:108351. [PMID: 38430613 PMCID: PMC11073919 DOI: 10.1016/j.ymgme.2024.108351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 03/05/2024]
Abstract
Fatty acid oxidation disorders (FAODs) are a family of rare, genetic disorders that affect any part of the fatty acid oxidation pathway. Patients present with severe phenotypes, such as hypoketotic hypoglycemia, cardiomyopathy, and rhabdomyolysis, and currently manage these symptoms by the avoidance of fasting and maintaining a low-fat, high-carbohydrate diet. Because knowledge about FAODs is limited due to the small number of patients, rodent models have been crucial in learning more about these disorders, particularly in studying the molecular mechanisms involved in different phenotypes and in evaluating treatments for patients. The purpose of this review is to present the different FAOD mouse models and highlight the benefits and limitations of using these models. Specifically, we discuss the phenotypes of the available FAOD mouse models, the potential molecular causes of prominent FAOD phenotypes that have been studied using FAOD mouse models, and how FAOD mouse models have been used to evaluate treatments for patients.
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Affiliation(s)
- Shannon J Babcock
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA.
| | - Sander M Houten
- Deparment of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Melanie B Gillingham
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
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Paskeh MDA, Ghadyani F, Hashemi M, Abbaspour A, Zabolian A, Javanshir S, Razzazan M, Mirzaei S, Entezari M, Goharrizi MASB, Salimimoghadam S, Aref AR, Kalbasi A, Rajabi R, Rashidi M, Taheriazam A, Sethi G. Biological impact and therapeutic perspective of targeting PI3K/Akt signaling in hepatocellular carcinoma: Promises and Challenges. Pharmacol Res 2023; 187:106553. [PMID: 36400343 DOI: 10.1016/j.phrs.2022.106553] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/09/2022] [Accepted: 11/10/2022] [Indexed: 11/17/2022]
Abstract
Cancer progression results from activation of various signaling networks. Among these, PI3K/Akt signaling contributes to proliferation, invasion, and inhibition of apoptosis. Hepatocellular carcinoma (HCC) is a primary liver cancer with high incidence rate, especially in regions with high prevalence of viral hepatitis infection. Autoimmune disorders, diabetes mellitus, obesity, alcohol consumption, and inflammation can also lead to initiation and development of HCC. The treatment of HCC depends on the identification of oncogenic factors that lead tumor cells to develop resistance to therapy. The present review article focuses on the role of PI3K/Akt signaling in HCC progression. Activation of PI3K/Akt signaling promotes glucose uptake, favors glycolysis and increases tumor cell proliferation. It inhibits both apoptosis and autophagy while promoting HCC cell survival. PI3K/Akt stimulates epithelial-to-mesenchymal transition (EMT) and increases matrix-metalloproteinase (MMP) expression during HCC metastasis. In addition to increasing colony formation capacity and facilitating the spread of tumor cells, PI3K/Akt signaling stimulates angiogenesis. Therefore, silencing PI3K/Akt signaling prevents aggressive HCC cell behavior. Activation of PI3K/Akt signaling can confer drug resistance, particularly to sorafenib, and decreases the radio-sensitivity of HCC cells. Anti-cancer agents, like phytochemicals and small molecules can suppress PI3K/Akt signaling by limiting HCC progression. Being upregulated in tumor tissues and clinical samples, PI3K/Akt can also be used as a biomarker to predict patients' response to therapy.
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Affiliation(s)
- Mahshid Deldar Abad Paskeh
- Department of Genetics, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Farhikhtegan Medical Convergence sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Fatemeh Ghadyani
- Farhikhtegan Medical Convergence sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mehrdad Hashemi
- Department of Genetics, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Farhikhtegan Medical Convergence sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Alireza Abbaspour
- Cellular and Molecular Research Center,Qazvin University of Medical Sciences, Qazvin, Iran
| | - Amirhossein Zabolian
- Resident of department of Orthopedics, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Salar Javanshir
- Young Researchers and Elite Club, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mehrnaz Razzazan
- Medical Student, Student Research Committee, Golestan University of Medical Sciences, Gorgan, Iran
| | - Sepideh Mirzaei
- Department of Biology, Faculty of Science, Islamic Azad University, Science and Research Branch, Tehran, Iran
| | - Maliheh Entezari
- Department of Genetics, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Farhikhtegan Medical Convergence sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | | | - Shokooh Salimimoghadam
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Amir Reza Aref
- Belfer Center for Applied Cancer Science, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA; Translational Sciences, Xsphera Biosciences Inc. 6, Tide Street, Boston, MA 02210, USA
| | - Alireza Kalbasi
- Department of Pharmacy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Romina Rajabi
- Faculty of Veterinary Medicine, Islamic Azad University, Science and Research Branch, Tehran, Iran.
| | - Mohsen Rashidi
- Department Pharmacology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran; The Health of Plant and Livestock Products Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
| | - Afshin Taheriazam
- Farhikhtegan Medical Convergence sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Orthopedics, Faculty of medicine, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore; NUS Centre for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore.
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Identification of Genetic Effects of ACADVL and IRF6 Genes with Milk Production Traits of Holstein Cattle in China. Genes (Basel) 2022; 13:genes13122393. [PMID: 36553659 PMCID: PMC9777597 DOI: 10.3390/genes13122393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 12/02/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022] Open
Abstract
With the development of high-throughput sequencing, RNA sequencing has been widely used in the identification of candidate genes for complex traits in livestock, and the functional genes and mutations with large genetic effects on milk production traits can provide molecular information for marker-assisted selection to increase the selection accuracy and accelerate genetic gain in dairy cattle. Our previous study on the liver transcriptome of Holstein cows found that acyl-CoA dehydrogenase (ACADVL) and interferon regulatory factor 6 (IRF6) are differentially expressed between dry and peak lactation periods, as well as that they are involved in lipid metabolism and the proliferation and differentiation of mammary epithelial cells. Thus, the two genes were considered candidates for milk traits. Hence, this study further collected 1186 Holstein cows from 110 sire families to investigate their genetic associations with milk yield and composition traits. By resequencing the entire exons and 2000 bp of the 5' and 3' flanking regions of the two genes, we identified eight SNPs in ACADVL and eight SNPs in IRF6. Subsequent single-locus association analyses showed that the eight SNPs in ACADVL were all significantly associated with milk fat yield, fat percentage, and protein yield (p values ≤ 0.0001-0.0414), and the eight SNPs in IRF6 were associated with milk, fat, and protein yields in the first or second lactation (p values ≤ 0.0001-0.0467). Using Haploview 4.2, one haplotype block with eight of the SNPs in ACADVL (D' = 0.99-1.00) and two haplotype blocks in IRF6 with three of the SNPs in each were observed (D' = 0.98-1.00). Similarly, the haplotype combinations of ACADVL were significantly associated with milk yield, fat percentage, fat yield, and protein yield in the two lactations (p values ≤ 0.0001-0.0125), and those of IRF6 were associated with five milk traits (p values ≤ 0.0001-0.0263). Furthermore, with the JASPAR software, it was predicted that the SNPs 19:g.26933503T>C in ACADVL and 16:g.73501985G>A in IRF6 changed the transcription factor binding sites of ZEB1, PLAGL2, and RHOXF1, implying their impacts on the expressions of the corresponding genes. Our findings demonstrated that the ACADVL and IRF6 genes have significant genetic effects on milk yield and composition traits, and the valuable SNPs might be used as genetic markers for genomic selection programs in dairy cattle.
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Zhu QW, Yu Y, Zhang Y, Wang XH. VLCAD inhibits the proliferation and invasion of hepatocellular cancer cells through regulating PI3K/AKT axis. Clin Transl Oncol 2022; 24:864-874. [PMID: 35001339 DOI: 10.1007/s12094-021-02733-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/02/2021] [Indexed: 12/12/2022]
Abstract
PURPOSE Very-long-chain acyl-CoA dehydrogenase (VLCAD) is an essential mediator in fatty acid metabolism. The progression of human hepatocellular carcinoma (HCC) is closely associated with the disorder of energy supply. Here, we aimed to investigate the role and underlying molecule mechanism of VLCAD in pathological process of HCC. METHODS In this study, VLCAD was induced silencing and overexpression using small hairpin RNA (shRNA) and lentiviral-mediated vector in HCC cell lines. The proliferation of HCC cells was determined using CCK-8 assay. Transwell assay and lung metastasis were performed to analysis cell metastasis in vitro and in vivo. ECAR and OCR were used to evaluate the activity of glycolysis and mitochondrial oxidative phosphorylation. RESULTS Our data indicated that VLCAD was downregulated in human HCC tissues and cells. VLCAD overexpression strongly suppressed the proliferation and metastasis of HCC cells associating with the decrease of ATP accumulation and glycolysis activity. Importantly, the PI3K/AKT inhibitor LY294002 strongly abolished the role of shVLCAD in HCC cells. Our results suggested that VLCAD suppressed the growth and metastasis in HCC cells by inhibiting the activities of glycolysis and mitochondrial oxidative phosphorylation metabolism via PI3K/AKT pathway. CONCLUSIONS Together, present findings not only demonstrated the protective role of and molecular network of VLCAD in HCC cells but also indicated its and potential use as a target in the therapy of HCC.
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Affiliation(s)
- Q W Zhu
- Department of General Surgery, The Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, Changzhou, Jiangsu, China
| | - Yue Yu
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, Jiangsu, China
| | - Yu Zhang
- Department of Pharmacology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - X H Wang
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Key Laboratory of Liver Transplantation, NHC Key Laboratory of Living Donor Liver Transplantation (Nanjing Medical University), Chinese Academy of Medical Sciences, Nanjing, Jiangsu, China.
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Altered Metabolic Flexibility in Inherited Metabolic Diseases of Mitochondrial Fatty Acid Metabolism. Int J Mol Sci 2021; 22:ijms22073799. [PMID: 33917608 PMCID: PMC8038842 DOI: 10.3390/ijms22073799] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/03/2021] [Accepted: 04/05/2021] [Indexed: 12/14/2022] Open
Abstract
In general, metabolic flexibility refers to an organism's capacity to adapt to metabolic changes due to differing energy demands. The aim of this work is to summarize and discuss recent findings regarding variables that modulate energy regulation in two different pathways of mitochondrial fatty metabolism: β-oxidation and fatty acid biosynthesis. We focus specifically on two diseases: very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) and malonyl-CoA synthetase deficiency (acyl-CoA synthetase family member 3 (ACSF3)) deficiency, which are both characterized by alterations in metabolic flexibility. On the one hand, in a mouse model of VLCAD-deficient (VLCAD-/-) mice, the white skeletal muscle undergoes metabolic and morphologic transdifferentiation towards glycolytic muscle fiber types via the up-regulation of mitochondrial fatty acid biosynthesis (mtFAS). On the other hand, in ACSF3-deficient patients, fibroblasts show impaired mitochondrial respiration, reduced lipoylation, and reduced glycolytic flux, which are compensated for by an increased β-oxidation rate and the use of anaplerotic amino acids to address the energy needs. Here, we discuss a possible co-regulation by mtFAS and β-oxidation in the maintenance of energy homeostasis.
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Goetzman ES, Bharathi SS, Zhang Y, Zhao XJ, Dobrowolski SF, Peasley K, Sims-Lucas S, Monga SP. Impaired mitochondrial medium-chain fatty acid oxidation drives periportal macrovesicular steatosis in sirtuin-5 knockout mice. Sci Rep 2020; 10:18367. [PMID: 33110171 PMCID: PMC7591893 DOI: 10.1038/s41598-020-75615-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 10/08/2020] [Indexed: 12/14/2022] Open
Abstract
Medium-chain triglycerides (MCT), containing C8-C12 fatty acids, are used to treat several pediatric disorders and are widely consumed as a nutritional supplement. Here, we investigated the role of the sirtuin deacylase Sirt5 in MCT metabolism by feeding Sirt5 knockout mice (Sirt5KO) high-fat diets containing either C8/C10 fatty acids or coconut oil, which is rich in C12, for five weeks. Coconut oil, but not C8/C10 feeding, induced periportal macrovesicular steatosis in Sirt5KO mice. 14C-C12 degradation was significantly reduced in Sirt5KO liver. This decrease was localized to the mitochondrial β-oxidation pathway, as Sirt5KO mice exhibited no change in peroxisomal C12 β-oxidation. Endoplasmic reticulum ω-oxidation, a minor fatty acid degradation pathway known to be stimulated by C12 accumulation, was increased in Sirt5KO liver. Mice lacking another mitochondrial C12 oxidation enzyme, long-chain acyl-CoA dehydrogenase (LCAD), also developed periportal macrovesicular steatosis when fed coconut oil, confirming that defective mitochondrial C12 oxidation is sufficient to induce the steatosis phenotype. Sirt5KO liver exhibited normal LCAD activity but reduced mitochondrial acyl-CoA synthetase activity with C12. These studies reveal a role for Sirt5 in regulating the hepatic response to MCT and may shed light into the pathogenesis of periportal steatosis, a hallmark of human pediatric non-alcoholic fatty liver disease.
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Affiliation(s)
- Eric S Goetzman
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Pittsburgh Liver Research Center, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - Sivakama S Bharathi
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yuxun Zhang
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Xue-Jun Zhao
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Steven F Dobrowolski
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kevin Peasley
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sunder Sims-Lucas
- Department of Pediatrics, Children's Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Satdarshan P Monga
- Division of Experimental Pathology, Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Pittsburgh Liver Research Center, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Knottnerus SJG, van Harskamp D, Schierbeek H, Bleeker JC, Crefcoeur LL, Ferdinandusse S, van Goudoever JB, Houtkooper RH, IJlst L, Langeveld M, Wanders RJA, Vaz FM, Wijburg FA, Visser G. Exploring the metabolic fate of medium-chain triglycerides in healthy individuals using a stable isotope tracer. Clin Nutr 2020; 40:1396-1404. [PMID: 32948349 DOI: 10.1016/j.clnu.2020.08.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/09/2020] [Accepted: 08/27/2020] [Indexed: 12/29/2022]
Abstract
BACKGROUND & AIMS Medium chain triglyceride (MCT) supplementation is often recommended as treatment for patients with long-chain fatty acid β-oxidation (lcFAO) disorders, since they can be utilized as an energy source without the use of the defective enzyme. However, studies in mice and preterm infants suggest that not all medium-chain fatty acids (MCFA) are oxidized and may undergo elongation to long-chain fatty acids (LCFA). In this single blinded study, we explored the metabolic fates of MCT in healthy individuals using a 13C-labeled MCT tracer. METHOD Three healthy males in rest received on two test days a primed continuous infusion of glyceryl tri[1,2,3,4-13C4]-octanoate with either an isocaloric supplementation of 1) exclusively MCT (MCT-only) or 2) a mixture of MCT, proteins and carbohydrates (MCT-mix). Gas chromatography - combustion - isotope ratio mass spectrometry (GC-C-IRMS) was used to determine 13C-enrichment of long-chain fatty acids in plasma and of 13CO2 in exhaled air. RESULTS When provided as single energy source, an estimated 42% of administered MCT was converted to CO2. In combination with carbohydrates and proteins in the diet, oxidation of MCT was higher (62%). In both diets <1% of 13C-label was incorporated in LCFA in plasma, indicating that administered MCT underwent chain-elongation to LCT. CONCLUSIONS Although the relative MCT oxidation rate was higher when combined with carbohydrates and protein, quantitatively more MCT was oxidized when given an isocaloric meal with solely MCT. As these results were obtained in the resting state opposed to during exercise, it is too early to give a recommendation concerning the use of MCT in lcFAO disorders. The data show that in resting healthy individuals only a very small part of the MCT is traced back as LCFA in plasma, suggesting that MCT treatment does not result in a large LCFA burden, however further research on storage of MCT in tissues is warranted. REGISTRATION The study was registered in the Nederlands Trialregister. Protocol ID: Trial NL7417 (NTR7650).
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Affiliation(s)
- Suzan J G Knottnerus
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands; Section Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584, EA, Utrecht, the Netherlands
| | - Dewi van Harskamp
- Amsterdam UMC, University of Amsterdam, Stable Isotope Research Laboratory, Endocrinology, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands; Amsterdam UMC, University of Amsterdam, Vrije Universiteit, Emma's Children's Hospital, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Henk Schierbeek
- Amsterdam UMC, University of Amsterdam, Stable Isotope Research Laboratory, Endocrinology, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands; Amsterdam UMC, University of Amsterdam, Vrije Universiteit, Emma's Children's Hospital, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Jeannette C Bleeker
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Loek L Crefcoeur
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands; Section Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584, EA, Utrecht, the Netherlands
| | - Sacha Ferdinandusse
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Johannes B van Goudoever
- Amsterdam UMC, University of Amsterdam, Vrije Universiteit, Emma's Children's Hospital, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Riekelt H Houtkooper
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Lodewijk IJlst
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Mirjam Langeveld
- Amsterdam UMC, University of Amsterdam, Department of Endocrinology and Metabolism, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Ronald J A Wanders
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Frédéric M Vaz
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Frits A Wijburg
- Amsterdam UMC, University of Amsterdam, Vrije Universiteit, Emma's Children's Hospital, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands
| | - Gepke Visser
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Cardiovascular Sciences, Amsterdam Gastroenterology Endocrinology and Metabolism, Meibergdreef 9, 1105, AZ, Amsterdam, the Netherlands; Section Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center Utrecht, Lundlaan 6, 3584, EA, Utrecht, the Netherlands.
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Ribas GS, Vargas CR. Evidence that Oxidative Disbalance and Mitochondrial Dysfunction are Involved in the Pathophysiology of Fatty Acid Oxidation Disorders. Cell Mol Neurobiol 2020; 42:521-532. [PMID: 32876899 DOI: 10.1007/s10571-020-00955-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/22/2020] [Indexed: 12/15/2022]
Abstract
Mitochondrial fatty acid β-oxidation disorders (FAODs) are a group of about 20 diseases which are caused by specific mutations in genes that codify proteins or enzymes involved in the fatty acid transport and mitochondrial β-oxidation. As a consequence of these inherited metabolic defects, fatty acids can not be used as an appropriate energetic source during special conditions, such as prolonged fasting, exercise or other catabolic states. Therefore, patients usually present hepatopathy, cardiomyopathy, severe skeletal myopathy and neuropathy, besides biochemical features like hypoketotic hypoglycemia, metabolic acidosis, hypotony and hyperammonemia. This set of symptoms seems to be related not only with the energy deficiency, but also with toxic effects provoked by fatty acids and carnitine derivatives accumulated in the tissues of the patients. The understanding of the mechanisms by which these metabolites provoke tissue injury in FAODs is crucial for the developmental of novel therapeutic strategies that promote increased life expectancy, as well as improved life quality for patients. In this sense, the objective of this review is to present evidence from the scientific literature on the role of oxidative damage and mitochondrial dysfunction in the pathogenesis of the most prevalent FAODs: medium-chain acyl-CoA dehydrogenase (MCAD), long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) and very long-chain acyl-CoA dehydrogenase (VLCAD) deficiencies. It is expected that the findings presented in this review, obtained from both animal model and patients studies, may contribute to a better comprehension of the pathophysiology of these diseases.
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Affiliation(s)
- Graziela Schmitt Ribas
- Departamento de Análises Clínicas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Carmen Regla Vargas
- Departamento de Análises Clínicas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
- Serviço de Genética Médica, Hospital de Clíınicas de Porto Alegre, Ramiro Barcelos, 2350, Porto Alegre, RS, 90035-003, Brazil.
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Bleeker JC, Visser G, Clarke K, Ferdinandusse S, de Haan FH, Houtkooper RH, IJlst L, Kok IL, Langeveld M, van der Pol WL, de Sain‐van der Velden MGM, Sibeijn‐Kuiper A, Takken T, Wanders RJA, van Weeghel M, Wijburg FA, van der Woude LH, Wüst RCI, Cox PJ, Jeneson JAL. Nutritional ketosis improves exercise metabolism in patients with very long-chain acyl-CoA dehydrogenase deficiency. J Inherit Metab Dis 2020; 43:787-799. [PMID: 31955429 PMCID: PMC7384182 DOI: 10.1002/jimd.12217] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/23/2019] [Accepted: 01/14/2020] [Indexed: 12/11/2022]
Abstract
A maladaptive shift from fat to carbohydrate (CHO) oxidation during exercise is thought to underlie myopathy and exercise-induced rhabdomyolysis in patients with fatty acid oxidation (FAO) disorders. We hypothesised that ingestion of a ketone ester (KE) drink prior to exercise could serve as an alternative oxidative substrate supply to boost muscular ATP homeostasis. To establish a rational basis for therapeutic use of KE supplementation in FAO, we tested this hypothesis in patients deficient in Very Long-Chain acyl-CoA Dehydrogenase (VLCAD). Five patients (range 17-45 y; 4 M/1F) patients were included in an investigator-initiated, randomised, blinded, placebo-controlled, 2-way cross-over study. Patients drank either a KE + CHO mix or an isocaloric CHO equivalent and performed 35 minutes upright cycling followed by 10 minutes supine cycling inside a Magnetic Resonance scanner at individual maximal FAO work rate (fatmax; approximately 40% VO2 max). The protocol was repeated after a 1-week interval with the alternate drink. Primary outcome measures were quadriceps phosphocreatine (PCr), Pi and pH dynamics during exercise and recovery assayed by in vivo 31 P-MR spectroscopy. Secondary outcomes included plasma and muscle metabolites and respiratory gas exchange recordings. Ingestion of KE rapidly induced mild ketosis and increased muscle BHB content. During exercise at FATMAX, VLCADD-specific plasma acylcarnitine levels, quadriceps glycolytic intermediate levels and in vivo Pi/PCr ratio were all lower in KE + CHO than CHO. These results provide a rational basis for future clinical trials of synthetic ketone ester supplementation therapy in patients with FAO disorders. Trial registration: ClinicalTrials.gov. Protocol ID: NCT03531554; METC2014.492; ABR51222.042.14.
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Affiliation(s)
- Jeannette C. Bleeker
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Metabolic Diseases, Emma Children's Hospital, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Gepke Visser
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Metabolic Diseases, Emma Children's Hospital, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Kieran Clarke
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Ferdinand H. de Haan
- ACHIEVE, Center for Applied Research, Faculty of HealthUniversity of Applied Sciences AmsterdamAmsterdamThe Netherlands
| | - Riekelt H. Houtkooper
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Lodewijk IJlst
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Irene L. Kok
- Department of Metabolic Diseases, Wilhelmina Children's HospitalUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Mirjam Langeveld
- Department of Endocrinology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - W. Ludo van der Pol
- Department of Neurology and Neurosurgery, Rudolf Magnus Institute of Neuroscience, Spieren voor Spieren KindercentrumUniversity Medical Center UtrechtUtrechtThe Netherlands
| | | | - Anita Sibeijn‐Kuiper
- Neuroimaging Center, Department of Biomedical Sciences of Cells and SystemsUniversity Medical Center GroningenGroningenThe Netherlands
| | - Tim Takken
- Center for Child Development & Exercise, Department of Medical PhysiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Ronald J. A. Wanders
- Department of Metabolic Diseases, Emma Children's Hospital, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Michel van Weeghel
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
- Laboratory Genetic Metabolic Diseases, Amsterdam UMCUniversity of Amsterdam, Amsterdam Cardiovascular SciencesAmsterdamThe Netherlands
- Core Facility Metabolomics, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Frits A. Wijburg
- Department of Metabolic Diseases, Emma Children's Hospital, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Luc H. van der Woude
- Human Movement SciencesUniversity Medical Center GroningenGroningenThe Netherlands
| | - Rob C. I. Wüst
- Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Pete J. Cox
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUK
| | - Jeroen A. L. Jeneson
- Neuroimaging Center, Department of Biomedical Sciences of Cells and SystemsUniversity Medical Center GroningenGroningenThe Netherlands
- Center for Child Development & Exercise, Department of Medical PhysiologyUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Radiology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
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10
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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] [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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11
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Transcriptome analysis suggests a compensatory role of the cofactors coenzyme A and NAD + in medium-chain acyl-CoA dehydrogenase knockout mice. Sci Rep 2019; 9:14539. [PMID: 31601874 PMCID: PMC6787083 DOI: 10.1038/s41598-019-50758-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 09/13/2019] [Indexed: 12/12/2022] Open
Abstract
During fasting, mitochondrial fatty-acid β-oxidation (mFAO) is essential for the generation of glucose by the liver. Children with a loss-of-function deficiency in the mFAO enzyme medium-chain acyl-Coenzyme A dehydrogenase (MCAD) are at serious risk of life-threatening low blood glucose levels during fasting in combination with intercurrent disease. However, a subset of these children remains asymptomatic throughout life. In MCAD-deficient (MCAD-KO) mice, glucose levels are similar to those of wild-type (WT) mice, even during fasting. We investigated if metabolic adaptations in the liver may underlie the robustness of this KO mouse. WT and KO mice were given a high- or low-fat diet and subsequently fasted. We analyzed histology, mitochondrial function, targeted mitochondrial proteomics, and transcriptome in liver tissue. Loss of MCAD led to a decreased capacity to oxidize octanoyl-CoA. This was not compensated for by altered protein levels of the short- and long-chain isoenzymes SCAD and LCAD. In the transcriptome, we identified subtle adaptations in the expression of genes encoding enzymes catalyzing CoA- and NAD(P)(H)-involving reactions and of genes involved in detoxification mechanisms. We discuss how these processes may contribute to robustness in MCAD-KO mice and potentially also in asymptomatic human subjects with a complete loss of MCAD activity.
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12
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Wehbe Z, Alatibi K, Jellusova J, Spiekerkoetter U, Tucci S. The fate of medium-chain fatty acids in very long-chain acyl‑CoA dehydrogenase deficiency (VLCADD): A matter of sex? Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1591-1605. [PMID: 31394165 DOI: 10.1016/j.bbalip.2019.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/10/2019] [Accepted: 08/02/2019] [Indexed: 12/22/2022]
Abstract
Medium-chain-triglycerides (MCT) are widely applied in the treatment of long-chain fatty acid oxidation disorders (lcFAOD). Long-term treatment with MCT led to a sexually dimorphic response in the mouse model of very-long-chain-acyl-CoA-dehydrogenase-deficiency (VLCAD-/-) with the subsequent development of a metabolic syndrome in female mice. In order to evaluate the molecular mechanisms responsible for this sex specific response we performed a comprehensive metabolic phenotyping, SILAC-based quantitative proteomics and characterized the involved signaling pathways by western blot analysis and gene expression. WT and VLCAD-/- mice showed strong sex-dependent differences in basal metabolism and expression of proteins involved in the distinct metabolic pathways, even more prominent after treatment with octanoate. The investigation of molecular mechanisms responsible for the sexual dimorphisms delineated the selective activation of the ERK/mTORc1 signaling pathway leading to an increased biosynthesis and elongation of fatty acids in VLCAD-/- females. In contrast, octanoate induced the activation of ERK/PPARγ pathway and the subsequent upregulation of peroxisomal β‑oxidation in males. We here provide first evidence that sex has to be considered as important variable in disease phenotype. These findings may have implications on treatment strategies in the different sexes.
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Affiliation(s)
- Zeinab Wehbe
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics and Adolescent Medicine, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Mathildenstrasse 1, Freiburg, Germany; University of Freiburg, Faculty of Biology, Schaenzlestrasse 1, D-79104 Freiburg, Germany
| | - Khaled Alatibi
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics and Adolescent Medicine, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Mathildenstrasse 1, Freiburg, Germany; University of Freiburg, Faculty of Biology, Schaenzlestrasse 1, D-79104 Freiburg, Germany
| | - Julia Jellusova
- Department of Molecular Immunology, Institute of Biology III at the Faculty of Biology, Albert-Ludwigs-University of Freiburg, Schänzlestr. 1, 79104 Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, Albert-Ludwigs-University of Freiburg, Schänzlestr. 18, 79104 Freiburg, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics and Adolescent Medicine, Center for Pediatrics and Adolescent Medicine, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Mathildenstrasse 1, Freiburg, Germany
| | - Sara Tucci
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics and Adolescent Medicine, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Mathildenstrasse 1, Freiburg, Germany.
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13
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Guimarães J, Bargut TCL, Mandarim-de-Lacerda CA, Aguila MB. Medium-chain triglyceride reinforce the hepatic damage caused by fructose intake in mice. Prostaglandins Leukot Essent Fatty Acids 2019; 140:64-71. [PMID: 30553406 DOI: 10.1016/j.plefa.2018.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 11/06/2018] [Accepted: 11/08/2018] [Indexed: 01/16/2023]
Abstract
We aimed to investigate the effects of medium-chain triglyceride oil on the high fructose diet-provoked hepatic abnormalities in mice. We used C57bl/6 mice of 3-months-old divided into four groups for 12 weeks: control (C), control with MCT (C-MCT), fructose (F), and fructose with MCT (F-MCT). We investigated food and water intake, body mass, blood pressure, glucose tolerance, plasma and liver biochemistry, hepatic protein and gene expression. There were no changes in body mass, food intake and glucose tolerance among the groups. The F group presented increased water intake and blood pressure associated with hepatic steatosis and elevated de novo lipogenesis, beta-oxidation, mitochondrial biogenesis and inflammation in the liver. Surprisingly, the C-MCT group also showed hepatic steatosis and inflammation in the liver, and the F-MCT group had no exacerbations of fructose-induced abnormalities, showing marked hepatic steatosis, lipogenesis de novo and hepatic inflammation. The MCT oil groups also presented increased beta-oxidation and mitochondrial biogenesis. In conclusion, MCT oil showed detrimental hepatic effects and should be used with caution, especially in the presence of hepatic alterations.
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Affiliation(s)
- Janaina Guimarães
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Carlos Alberto Mandarim-de-Lacerda
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Marcia Barbosa Aguila
- Laboratory of Morphometry, Metabolism and Cardiovascular Diseases, Biomedical Center, Institute of Biology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
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14
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Tucci S. Very long-chain acyl-CoA dehydrogenase (VLCAD-) deficiency-studies on treatment effects and long-term outcomes in mouse models. J Inherit Metab Dis 2017; 40:317-323. [PMID: 28247148 DOI: 10.1007/s10545-017-0016-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 12/31/2022]
Abstract
Very-long-chain-acyl-CoA-dehydrogenase deficiency is the most common disorder of mitochondrial long-chain fatty acid (LCFA) oxidation, with an incidence of 1:50,000-1:100,000 in newborns. Catabolic situations contribute to the aggravation of symptoms and induce severe metabolic derangement. Treatment for VLCAD-deficiency includes avoidance of fasting and a long-chain fat-restricted and fat-modified diet in which LCFAs are fully or partially replaced by medium-chain triglycerides (MCT). The aim of this work was to investigate the outcome and the effects of long-term treatment in a mouse model of VLCAD-deficiency. The application of a single MCT bolus in a mouse model of VLCAD-deficiency (VLCAD-/- mice) immediately prior to exercise protected the muscles from the accumulation of acylcarnitines providing the required energy and it did not affect hepatic lipid metabolism. However, when MCT was applied over the course of a year as a regular part of the diet, female VLCAD-/- mice developed a severe clinical phenotype comparable to the human metabolic syndrome. Indeed, they were characterized by massive visceral fat infiltration, hepatosteatosis, disturbed fatty acid composition, hyperlipidemia, and systemic oxidative stress. In contrast, male VLCAD-/- mice seemed to be protected and displayed only signs of insulin resistance. Besides the sex-specific response to MCT supplementation with regard to the lipid metabolism, all VLCAD-/- mice developed progressive cardiac dysfunction over time which worsened when they were treated with regular MCT resulting in severe dilated cardiomyopathy. While long term use of MCT oil in mice has adverse effects, no such effects have been demonstrated in humans, likely reflecting the differences in long chain fatty acid oxidation between the two species.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, Medical Centre - University of Freiburg, Mathildenstrasse 1, 79106, Freiburg, Germany.
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15
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Chamma CMDO, Bargut TCL, Mandarim-de-Lacerda CA, Aguila MB. A rich medium-chain triacylglycerol diet benefits adiposity but has adverse effects on the markers of hepatic lipogenesis and beta-oxidation. Food Funct 2017; 8:778-787. [DOI: 10.1039/c6fo01663d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
We investigated the increasing amounts of medium-chain triacylglycerol (MCT) in the diet on hepatic lipid metabolism.
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Affiliation(s)
- Carolina Maria de Oliveira Chamma
- Laboratory of Morphometry
- Metabolism and Cardiovascular Diseases
- Biomedical Center
- Institute of Biology
- State University of Rio de Janeiro
| | - Thereza Cristina Lonzetti Bargut
- Laboratory of Morphometry
- Metabolism and Cardiovascular Diseases
- Biomedical Center
- Institute of Biology
- State University of Rio de Janeiro
| | | | - Marcia Barbosa Aguila
- Laboratory of Morphometry
- Metabolism and Cardiovascular Diseases
- Biomedical Center
- Institute of Biology
- State University of Rio de Janeiro
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16
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Tucci S, Floegel U, Beermann F, Behringer S, Spiekerkoetter U. Triheptanoin: long-term effects in the very long-chain acyl-CoA dehydrogenase-deficient mouse. J Lipid Res 2016; 58:196-207. [PMID: 27884962 DOI: 10.1194/jlr.m072033] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/07/2016] [Indexed: 12/31/2022] Open
Abstract
A rather new approach in the treatment of long-chain fatty acid oxidation disorders is represented by triheptanoin, a triglyceride with three medium-odd-chain heptanoic acids (C7), due to its anaplerotic potential. We here investigate the effects of a 1-year triheptanoin-based diet on the clinical phenotype of very long-chain-acyl-CoA-dehydrogenase-deficient (VLCAD-/-) mice. The cardiac function was assessed in VLCAD-/- mice by in vivo MRI. Metabolic adaptations were identified by the expression of genes regulating energy metabolism and anaplerotic processes using real-time PCR, and the results were correlated with the measurement of the glycolytic enzymes pyruvate dehydrogenase and pyruvate kinase. Finally, the intrahepatic lipid accumulation and oxidative stress in response to the long-term triheptanoin diet were assessed. Triheptanoin was not able to prevent the development of systolic dysfunction in VLCAD-/- mice despite an upregulation of cardiac glucose oxidation. Strikingly, the anaplerotic effects of triheptanoin were restricted to the liver. Despite this, the hepatic lipic content was increased upon triheptanoin supplementation. Our data demonstrate that the concept of anaplerosis does not apply to all tissues equally.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg, Germany
| | - Ulrich Floegel
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Frauke Beermann
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg, Germany
| | - Sidney Behringer
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Freiburg, Germany
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17
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Wang W, Palmfeldt J, Mohsen AW, Gregersen N, Vockley J. Fasting induces prominent proteomic changes in liver in very long chain Acyl-CoA dehydrogenase deficient mice. Biochem Biophys Rep 2016; 8:333-339. [PMID: 28955973 PMCID: PMC5613767 DOI: 10.1016/j.bbrep.2016.08.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 07/27/2016] [Accepted: 08/09/2016] [Indexed: 12/26/2022] Open
Abstract
Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency (VLCADD) is a clinically heterogeneous disorder of mitochondrial fatty acid β-oxidation usually identified through newborn screening. Genotype-phenotype correlations have been defined, but considerable clinical heterogeneity still exists. Symptoms are often induced by physiological stress such as fasting or intercurrent illness, setting it as an important example of environmental effects altering clinical course in an individual with a genetic disease. However, neither the cellular changes that predispose to this phenomenon nor the alterations it induces are well characterized. We examined the effects of fasting in a knockout mouse model to explore changes in global mitochondria protein profiles in liver and to investigate the physiologically relevant changes that lead to the clinical presentations. An isobaric tags for relative and absolute quantification (iTRAQ) labeling approach was employed to examine mitochondrial proteome changes in VLCAD deficient compared to wild type mice in the fed and fasted states. We identified numerous proteomic changes associated with the gene defect and fasting within relevant metabolic pathways. Few changes induced by fasting were shared between the VLCAD deficient and wild type mice, with more alterations found in the deficient mice on fasting. Particularly, fasting in the deficient mice could reverse the protective response in oxidative phosphorylation pathway seen in wild type animals. In addition, we found that changes in chaperone proteins including heat shock protein 60 (HSP60) and 10 (HSP10) during fasting differed between the two genotypes, highlighting the importance of these proteins in VLCAD deficiency. Finally, the effects on the liver proteome imposed by changes in fasted VLCAD deficient mice indicates that this environmental factor may be an inducer of both cellular and physiological changes. VLCAD deficient mice show significant changes in the proteome compared to wild type animals. Hypoglycemia induces different proteomic changes in VLCAD deficient mice than is seen in wild type animals. Multiple functional pathways are altered in VLCAD deficient animals. Proteomic changes in VLCAD deficient mice may help understand the physiologic ramifications of this deficiency in humans.
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Affiliation(s)
- Wei Wang
- Department of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiaotong University, Shanghai, China.,Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, USA
| | - Johan Palmfeldt
- Research Unit for Molecular Medicine, Institute of Clinical Medicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
| | - Al-Walid Mohsen
- Department of Pediatrics, School of Medicine, University of Pittsburgh, Pittsburgh, USA
| | - Niels Gregersen
- Research Unit for Molecular Medicine, Institute of Clinical Medicine, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark
| | - Jerry Vockley
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, USA.,Department of Pediatrics, School of Medicine, University of Pittsburgh, Pittsburgh, USA
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18
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Bauquier J, Stent A, Gibney J, Jerrett I, White J, Tennent-Brown B, Pearce A, Pitt J. Evidence for marsh mallow (Malva parviflora
) toxicosis causing myocardial disease and myopathy in four horses. Equine Vet J 2016; 49:307-313. [DOI: 10.1111/evj.12604] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 06/21/2016] [Indexed: 12/31/2022]
Affiliation(s)
- J. Bauquier
- Faculty of Veterinary and Agricultural Sciences; University of Melbourne; Werribee Victoria Australia
| | - A. Stent
- Faculty of Veterinary and Agricultural Sciences; University of Melbourne; Werribee Victoria Australia
| | - J. Gibney
- Victorian Department of Environment and Primary Industries; Bundoora Victoria Australia
| | - I. Jerrett
- Victorian Department of Environment and Primary Industries; Bundoora Victoria Australia
| | - J. White
- Faculty of Veterinary and Agricultural Sciences; University of Melbourne; Parkville Victoria Australia
| | - B. Tennent-Brown
- Faculty of Veterinary and Agricultural Sciences; University of Melbourne; Werribee Victoria Australia
| | - A. Pearce
- Golden Plains Equine; Bannockburn Victoria Australia
| | - J. Pitt
- Victorian Clinical Genetics Services; Royal Children's Hospital; Melbourne Victoria Australia
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Motlagh L, Golbik R, Sippl W, Zierz S. Stabilization of the thermolabile variant S113L of carnitine palmitoyltransferase II. NEUROLOGY-GENETICS 2016; 2:e53. [PMID: 27123472 PMCID: PMC4830186 DOI: 10.1212/nxg.0000000000000053] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 01/04/2016] [Indexed: 11/15/2022]
Abstract
OBJECTIVE Muscle carnitine palmitoyltransferase (CPT) II deficiency, the most common defect of lipid metabolism in muscle, is characterized by attacks of myoglobinuria without persistent muscle weakness. METHODS His6-N-hCPT2 (wild-type) and His6-N-hCPT2/S113L (variant) were produced recombinantly in prokaryotic host and characterized according to their functional and regulatory properties. RESULTS The wild-type and the variant S113L showed the same enzymatic activity and thermostability at 30°C. The mutated enzyme, however, revealed an abnormal thermal destabilization at 40°C and 45°C. This was consistent with an increased flexibility (B-factor) of the variant at 40°C compared with that of the wild-type shown by molecular dynamics analysis. Preincubation of the enzymes with l-carnitine and acyl-l-carnitines containing more than 10 carbons in the acyl side-chain stabilized the mutated enzyme against thermal inactivation. In contrast, palmitoyl-CoA destabilized both enzymes. CONCLUSIONS The problems in CPT II deficiency originating from the S113L mutation are not caused by the loss of catalytically active enzyme. They might be at least partially related to an impaired thermal stability of the protein. The lower thermodynamic stability of the variant might explain why fever and prolonged exertion provoke attacks of myoglobinuria in CPT II deficiency. The stabilization by acyl-l-carnitines might provide the basis for possible preventive therapy of CPT II deficiency.
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Affiliation(s)
- Leila Motlagh
- Department of Neurology (L.M., S.Z.), Institute of Biochemistry and Biotechnology (R.G.), and Institute of Pharmacy (W.S.), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Ralph Golbik
- Department of Neurology (L.M., S.Z.), Institute of Biochemistry and Biotechnology (R.G.), and Institute of Pharmacy (W.S.), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Wolfgang Sippl
- Department of Neurology (L.M., S.Z.), Institute of Biochemistry and Biotechnology (R.G.), and Institute of Pharmacy (W.S.), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Stephan Zierz
- Department of Neurology (L.M., S.Z.), Institute of Biochemistry and Biotechnology (R.G.), and Institute of Pharmacy (W.S.), Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
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20
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The odd-carbon medium-chain fatty triglyceride triheptanoin does not reduce hepatic steatosis. Clin Nutr 2015; 36:229-237. [PMID: 26778339 DOI: 10.1016/j.clnu.2015.11.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 10/18/2015] [Accepted: 11/06/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND & AIMS Non-alcoholic fatty-liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. Previously, we showed that a high-protein diet minimized diet-induced development of fatty liver and even reversed pre-existing steatosis. A high-protein diet leads to amino-acid catabolism, which in turn causes anaplerosis of the tricarboxylic-acid (TCA) cycle. Therefore, we hypothesized that anaplerosis of the TCA cycle could be responsible for the high-protein diet-induced improvement of NAFLD by channeling amino acids into the TCA cycle. Next we considered that an efficient anaplerotic agent, the odd-carbon medium-chain triglyceride triheptanoin (TH), might have similar beneficial effects. METHODS C57BL/6J mice were fed low-fat (8en%) or high-fat (42en%) oleate-containing diets with or without 15en% TH for 3 weeks. RESULTS TH treatment enhanced the hepatic capacity for fatty-acid oxidation by a selective increase in hepatic Ppara, Acox, and Cd36 expression, and a decline in plasma acetyl-carnitines. It also induced pyruvate cycling through an increased hepatic PCK1 protein concentration and it increased thermogenesis reflected by an increased Ucp2 mRNA content. TH, however, did not reduce hepatic lipid content. CONCLUSION The comparison of the present effects of dietary triheptanoin with a previous study by our group on protein supplementation shows that the beneficial effects of the high-protein diet are not mimicked by TH. This argues against anaplerosis as the sole explanatory mechanism for the anti-steatotic effect of a high-protein diet.
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21
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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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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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Tucci S, Behringer S, Spiekerkoetter U. De novo fatty acid biosynthesis and elongation in very long-chain acyl-CoA dehydrogenase-deficient mice supplemented with odd or even medium-chain fatty acids. FEBS J 2015; 282:4242-53. [PMID: 26284828 DOI: 10.1111/febs.13418] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/30/2015] [Accepted: 08/13/2015] [Indexed: 12/31/2022]
Abstract
An even medium-chain triglyceride (MCT)-based diet is the mainstay of treatment in very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency (VLCADD). Previous studies with magnetic resonance spectroscopy have shown an impact of MCT on the average fatty acid chain length in abdominal fat. We therefore assume that medium-chain fatty acids (MCFAs) are elongated and accumulate in tissue as long-chain fatty acids. In this study, we explored the hepatic effects of long-term supplementation with MCT or triheptanoin, an odd-chain C7-based triglyceride, in wild-type and VLCAD-deficient (VLCAD(-/-) ) mice after 1 year of supplementation as compared with a control diet. The de novo biosynthesis and elongation of fatty acids, and peroxisomal β-oxidation, were quantified by RT-PCR. This was followed by a comprehensive analysis of hepatic and cardiac fatty acid profiles by GC-MS. Long-term application of even and odd MCFAs strongly induced de novo biosynthesis and elongation of fatty acids in both wild-type and VLCAD(-/-) mice, leading to an alteration of the hepatic fatty acid profiles. We detected de novo-synthesized and elongated fatty acids, such as heptadecenoic acid (C17:1n9), eicosanoic acid (C20:1n9), erucic acid (C22:1n9), and mead acid (C20:3n9), that were otherwise completely absent in mice under control conditions. In parallel, the content of monounsaturated fatty acids was massively increased. Furthermore, we observed strong upregulation of peroxisomal β-oxidation in VLCAD(-/-) mice, especially when they were fed an MCT diet. Our data raise the question of whether long-term MCFA supplementation represents the most efficient treatment in the long term. Studies on the hepatic toxicity of triheptanoin are still ongoing.
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Affiliation(s)
- Sara Tucci
- Department of General Paediatrics, Centre for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Germany
| | - Sidney Behringer
- Department of General Paediatrics, Centre for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Germany
| | - Ute Spiekerkoetter
- Department of General Paediatrics, Centre for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Germany
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Tucci S, Flögel U, Spiekerkoetter U. Sexual dimorphism of lipid metabolism in very long-chain acyl-CoA dehydrogenase deficient (VLCAD-/-) mice in response to medium-chain triglycerides (MCT). Biochim Biophys Acta Mol Basis Dis 2015; 1852:1442-50. [PMID: 25887160 DOI: 10.1016/j.bbadis.2015.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/17/2015] [Accepted: 04/07/2015] [Indexed: 02/08/2023]
Abstract
Medium-chain triglycerides (MCT) are widely applied in the treatment of long-chain fatty acid oxidation disorders. Previously it was shown that long-term MCT supplementation strongly affects lipid metabolism in mice. We here investigate sex-specific effects in mice with very-long-chain-acyl-CoA dehydrogenase (VLCAD) deficiency in response to a long-term MCT modified diet. We quantified blood lipids, acylcarnitines, glucose, insulin and free fatty acids, as well as tissue triglycerides in the liver and skeletal muscle under a control and an MCT diet over 1 year. In addition, visceral and hepatic fat content and muscular intramyocellular lipids (IMCL) were assessed by in vivo(1)H magnetic resonance spectroscopy (MRS) techniques. The long-term application of an MCT diet induced a marked alteration of glucose homeostasis. However, only VLCAD-/- female mice developed a severe metabolic syndrome characterized by marked insulin resistance, dyslipidemia, severe hepatic and visceral steatosis, whereas VLCAD-/- males seemed to be protected and only presented with milder insulin resistance. Moreover, the highly saturated MCT diet is associated with a decreased hepatic stearoyl-CoA desaturase 1 (SCD1) activity in females aggravating the harmful effects of a saturated MCT diet. Long-term MCT supplementation deeply affects lipid metabolism in a sexual dimorphic manner resulting in a severe metabolic syndrome only in female mice. These findings are striking since the first signs of insulin resistance already occur in female VLCAD-/- mice during their reproductive period. How these metabolic adaptations are finally regulated needs to be determined. More important, the relevance of these findings for humans under these dietary modifications needs to be investigated.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany.
| | - Ulrich Flögel
- Department of Molecular Cardiology, Heinrich-Heine-University Duesseldorf, 40225 Düsseldorf, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany
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Tucci S, Krogmann A, Herebian D, Spiekerkoetter U. Renal response to short- and long-term exercise in very-long-chain acyl-CoA dehydrogenase-deficient (VLCAD(-/-)) mice. Mol Cell Pediatr 2014; 1:5. [PMID: 26567099 PMCID: PMC4530567 DOI: 10.1186/s40348-014-0005-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 07/22/2014] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Deficiency of very long-chain acyl-CoA dehydrogenase (VLCAD) is the most common disorder of mitochondrial β-oxidation of long-chain fatty acids. In order to maintain glucose homeostasis, the kidney and liver as the main gluconeogenic organs play an important role under conditions of impaired fatty acid oxidation. However, little is known about how a defective fatty acid oxidation machinery affects renal metabolism and function as well as renal energy supply especially during catabolic situations. METHODS In this study, we analyzed VLCAD(-/-) mice under different metabolic conditions such as after moderate (1 h) and intensive long-term (1 h twice per day over 2 weeks) physical exercise and after 24 h of fasting. We measured the oxidation rate of palmitoyl-CoA (C16-CoA) as well as the expression of genes involved in lipogenesis and renal failure. Oxidative stress was assessed by the function of antioxidant enzymes. Moreover, we quantified the content of glycogen and long-chain acylcarnitines in the kidney. RESULTS We observed a significant depletion in renal glycogen with a concomitant reduction in long-chain acylcarnitines, suggesting a substrate switch for energy production and an optimal compensation of impaired fatty acid oxidation in the kidney. In fact, the mutants did not show any signs of oxidative stress or renal failure under catabolic conditions. CONCLUSIONS Our data demonstrate that despite Acadvl ablation, the kidney of VLCAD(-/-) mice fully compensates for impaired fatty acid oxidation by enhanced glycogen utilization and preserves renal energy metabolism and function.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Mathildenstrasse 1, Freiburg, 79106, Germany.
| | - Antonia Krogmann
- Department of General Pediatrics, Neonatology and Children's Cardiology, University Children's Hospital, Duesseldorf, 40225, Germany.
| | - Diran Herebian
- Department of General Pediatrics, Neonatology and Children's Cardiology, University Children's Hospital, Duesseldorf, 40225, Germany.
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, Mathildenstrasse 1, Freiburg, 79106, Germany.
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Tucci S, Flögel U, Hermann S, Sturm M, Schäfers M, Spiekerkoetter U. Development and pathomechanisms of cardiomyopathy in very long-chain acyl-CoA dehydrogenase deficient (VLCAD(-/-)) mice. Biochim Biophys Acta Mol Basis Dis 2014; 1842:677-85. [PMID: 24530811 DOI: 10.1016/j.bbadis.2014.02.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 01/15/2014] [Accepted: 02/04/2014] [Indexed: 12/24/2022]
Abstract
Hypertrophic cardiomyopathy is a typical manifestation of very long-chain acyl-CoA dehydrogenase deficiency (VLCADD), the most common long-chain β-oxidation defects in humans; however in some patients cardiac function is fully compensated. Cardiomyopathy may also be reversed by supplementation of medium-chain triglycerides (MCT). We here characterize cardiac function of VLCAD-deficient (VLCAD(-/-)) mice over one year. Furthermore, we investigate the long-term effect of a continuous MCT diet on the cardiac phenotype. We assessed cardiac morphology and function in VLCAD(-/-) mice by in vivo MRI. Cardiac energetics were measured by (31)P-MRS and myocardial glucose uptake was quantified by positron-emission-tomography (PET). Metabolic adaptations were identified by the expression of genes regulating glucose and lipid metabolism using real-time-PCR. VLCAD(-/-) mice showed a progressive decrease in heart function over 12 months accompanied by a reduced phosphocreatine-to-ATP-ratio indicative of chronic energy deficiency. Long-term MCT supplementation aggravated the cardiac phenotype into dilated cardiomyopathy with features similar to diabetic heart disease. Cardiac energy production and function in mice with a β-oxidation defect cannot be maintained with age. Compensatory mechanisms are insufficient to preserve the cardiac energy state over time. However, energy deficiency by impaired β-oxidation and long-term MCT induce cardiomyopathy by different mechanisms. Cardiac MRI and MRS may be excellent tools to assess minor changes in cardiac function and energetics in patients with β-oxidation defects for preventive therapy.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany; Department of General Pediatrics, University Children's Hospital Duesseldorf, 40225 Duesseldorf, Germany.
| | - Ulrich Flögel
- Department of Molecular Cardiology, Heinrich Heine University Duesseldorf, 40225 Duesseldorf, Germany
| | - Sven Hermann
- European Institute for Molecular Imaging - EIMI, University of Muenster, 48149 Muenster, Germany
| | - Marga Sturm
- Department of General Pediatrics, University Children's Hospital Duesseldorf, 40225 Duesseldorf, Germany
| | - Michael Schäfers
- European Institute for Molecular Imaging - EIMI, University of Muenster, 48149 Muenster, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79106 Freiburg, Germany
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O’Neil D, Mendez-Figueroa H, Mistretta TA, Su C, Lane RH, Aagaard KM. Dysregulation of Npas2 leads to altered metabolic pathways in a murine knockout model. Mol Genet Metab 2013; 110:378-87. [PMID: 24067359 PMCID: PMC3874417 DOI: 10.1016/j.ymgme.2013.08.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 08/27/2013] [Indexed: 12/15/2022]
Abstract
In our primate model of maternal high fat diet exposure, we have described that fetal epigenomic modifications to the peripheral circadian Npas2 are associated with persistent alterations in fetal hepatic metabolism and non-alcoholic fatty liver. As the interaction of circadian response with metabolism is not well understood, we employed a murine knockout model to characterize the molecular mechanisms with which Npas2 reprograms the fetal hepatic metabolic response. cDNA was generated from Npas2-/- and +/+ (wild type) livers at day 2 (newborn) and at 25 weeks (adult) of life. Newborn samples were analyzed by exon array (n = 3/cohort). Independent pathway analysis software determined that the primary dysregulated pathway(s) in the Npas2-/- animals uniformly converged on lipid metabolism. Of particular interest, Ppargc1a, which integrates circadian and metabolism pathways, was significantly (p < .01) over expressed in newborn (1.7 fold) and adult (1.8 fold) Npas2-/- animals. These findings are consistent with an essential role for Npas2 in programming the peripheral circadian response and hepatic metabolism, which has not been previously described.
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Affiliation(s)
- Derek O’Neil
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine; Baylor College of Medicine; Houston, TX, 77030; USA
- Translational Biology and Molecular Medicine Program; Baylor College of Medicine; Houston, TX, 77030; USA
| | - Hector Mendez-Figueroa
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine; Baylor College of Medicine; Houston, TX, 77030; USA
| | - Toni-Ann Mistretta
- Department of Pathology; Texas Children’s Hospital, Baylor College of Medicine; Houston, TX, 77030; USA
| | - Chunliu Su
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine; Baylor College of Medicine; Houston, TX, 77030; USA
| | - Robert H. Lane
- Department of Pediatrics; University of Utah; Salt Lake City, UT, 84112; USA
| | - Kjersti M. Aagaard
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine; Baylor College of Medicine; Houston, TX, 77030; USA
- Translational Biology and Molecular Medicine Program; Baylor College of Medicine; Houston, TX, 77030; USA
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Tucci S, Pearson S, Herebian D, Spiekerkoetter U. Long-term dietary effects on substrate selection and muscle fiber type in very-long-chain acyl-CoA dehydrogenase deficient (VLCAD(-/-)) mice. Biochim Biophys Acta Mol Basis Dis 2013; 1832:509-16. [PMID: 23313579 DOI: 10.1016/j.bbadis.2013.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Revised: 12/28/2012] [Accepted: 01/04/2013] [Indexed: 12/11/2022]
Abstract
Dietary fat restriction and increased carbohydrate intake are part of treatment in very-long-chain acyl-CoA dehydrogenase (VLCAD)-deficiency, the most common defect of long-chain fatty acid oxidation. The long-term impact of these interventions is unknown. We characterized here the effects of a fat-reduced, carbohydrate-enriched diet and an increased fat intake on energy metabolism in a mouse model of VLCAD-deficiency. Wild-type and VLCAD(-/-) mice were fed one year either with a normal (5.1%), a high fat (10.6%) or a low-fat, carbohydrate-enriched (2.6%) diet. Dietary effects on genes involved in lipogenesis, energy homeostasis and substrate selection were quantified by real-time-PCR. Acylcarnitines as sign of impaired energy production were determined in dried blood spots and tissues. White skeletal muscle was analyzed for muscle fiber type as well as for glycogen and triglyceride content. Both dietary modifications induced enhanced triacylglyceride accumulation in skeletal muscle and inhibition of glucose oxidation. This was accompanied by an up-regulation of genes coding for oxidative muscle fiber type I and a marked accumulation of acylcarnitines, especially prominent in the heart (164±2.8 in VLCAD(-/-) vs. 82.3±2.1 in WT μmol/mg) under a low-fat, carbohydrate-enriched diet. We demonstrate here that both dietary interventions with respect to the fat content of the diet reverse endogenous compensatory mechanisms in muscle that have evolved in VLCAD(-/-) mice resulting in pronounced energy deficiency. In particular, the low-fat carbohydrate-enriched diet was not effective in the long term. Further experiments are necessary to define the optimal energy provision for fatty acid oxidation defects.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, University Hospital Freiburg, Germany.
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29
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Tucci S, Herebian D, Sturm M, Seibt A, Spiekerkoetter U. Tissue-specific strategies of the very-long chain acyl-CoA dehydrogenase-deficient (VLCAD-/-) mouse to compensate a defective fatty acid β-oxidation. PLoS One 2012; 7:e45429. [PMID: 23024820 PMCID: PMC3443214 DOI: 10.1371/journal.pone.0045429] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 08/16/2012] [Indexed: 12/31/2022] Open
Abstract
Very long-chain acyl-CoA dehydrogenase (VLCAD)-deficiency is the most common long-chain fatty acid oxidation disorder presenting with heterogeneous phenotypes. Similar to many patients with VLCADD, VLCAD-deficient mice (VLCAD−/−) remain asymptomatic over a long period of time. In order to identify the involved compensatory mechanisms, wild-type and VLCAD−/− mice were fed one year either with a normal diet or with a diet in which medium-chain triglycerides (MCT) replaced long-chain triglycerides, as approved intervention in VLCADD. The expression of the mitochondrial long-chain acyl-CoA dehydrogenase (LCAD) and medium-chain acyl-CoA dehydrogenase (MCAD) was quantified at mRNA and protein level in heart, liver and skeletal muscle. The oxidation capacity of the different tissues was measured by LC-MS/MS using acyl-CoA substrates with a chain length of 8 to 20 carbons. Moreover, in white skeletal muscle the role of glycolysis and concomitant muscle fibre adaptation was investigated. In one year old VLCAD−/− mice MCAD and LCAD play an important role in order to compensate deficiency of VLCAD especially in the heart and in the liver. However, the white gastrocnemius muscle develops alternative compensatory mechanism based on a different substrate selection and increased glucose oxidation. Finally, the application of an MCT diet over one year has no effects on LCAD or MCAD expression. MCT results in the VLCAD−/− mice only in a very modest improvement of medium-chain acyl-CoA oxidation capacity restricted to cardiac tissue. In conclusion, VLCAD−/− mice develop tissue-specific strategies to compensate deficiency of VLCAD either by induction of other mitochondrial acyl-CoA dehydrogenases or by enhancement of glucose oxidation. In the muscle, there is evidence of a muscle fibre type adaptation with a predominance of glycolytic muscle fibres. Dietary modification as represented by an MCT-diet does not improve these strategies long-term.
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MESH Headings
- Acyl-CoA Dehydrogenase, Long-Chain/deficiency
- Acyl-CoA Dehydrogenase, Long-Chain/genetics
- Acyl-CoA Dehydrogenase, Long-Chain/metabolism
- Acyl-CoA Dehydrogenases/genetics
- Acyl-CoA Dehydrogenases/metabolism
- Adaptation, Physiological
- Animals
- Citrate (si)-Synthase/metabolism
- Congenital Bone Marrow Failure Syndromes
- Diet
- Disease Models, Animal
- Fatty Acids/metabolism
- Homozygote
- Lipid Metabolism, Inborn Errors/genetics
- Lipid Metabolism, Inborn Errors/metabolism
- Liver/metabolism
- Mice
- Mice, Knockout
- Mitochondrial Diseases/genetics
- Mitochondrial Diseases/metabolism
- Muscle, Skeletal/metabolism
- Muscular Diseases/genetics
- Muscular Diseases/metabolism
- Myocardium/metabolism
- Organ Specificity
- Oxidation-Reduction
- Phenotype
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics and Neonatology, University Childreńs Hospital, Duesseldorf, Germany.
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30
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Keeler AM, Flotte TR. Cell and gene therapy for genetic diseases: inherited disorders affecting the lung and those mimicking sudden infant death syndrome. Hum Gene Ther 2012; 23:548-56. [PMID: 22642257 PMCID: PMC3392613 DOI: 10.1089/hum.2012.087] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 05/29/2012] [Indexed: 12/20/2022] Open
Abstract
Some of the first human gene therapy trials targeted diseases of the lung and provided important information that will continue to help shape future trials. Here we describe both cell and gene therapies for lung diseases such as cystic fibrosis and alpha-1 antitrypsin disorder as well as fatty acid oxidation disorders that mimic sudden infant death syndrome (SIDS). Human clinical gene therapy trials for cystic fibrosis and alpha-1 antitrypsin have been performed using a variety of vectors including adenovirus, adeno-associated virus, and nonviral vectors. No human clinical gene therapy trials have been performed for disorders of fatty acid oxidation; however, important proof-of-principle studies have been completed for multiple fatty acid oxidation disorders. Important achievements have been made and have yet to come for cell and gene therapies for disorders of the lung and those mimicking SIDS.
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Affiliation(s)
- Allison M Keeler
- Gene Therapy Center and Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA 01655, USA
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31
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Primassin S, Tucci S, Spiekerkoetter U. Hepatic and muscular effects of different dietary fat content in VLCAD deficient mice. Mol Genet Metab 2011; 104:546-51. [PMID: 21963783 DOI: 10.1016/j.ymgme.2011.09.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 09/08/2011] [Accepted: 09/08/2011] [Indexed: 12/23/2022]
Abstract
BACKGROUND Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is the most common long-chain fatty acid oxidation defect presenting with heterogeneous clinical phenotypes. Dietary fat plays a crucial role in disease pathogenesis and fat restriction is a common treatment measure. We here investigate the hepatic and muscular effects of a fat-enriched and a fat-restricted diet. METHODS VLCAD knock-out (KO) and wild-type (WT) mice are subjected to a fat-rich (10.6%), a fat-reduced (2.6%) or a regular mouse diet (5.1%) for 5 weeks. Analyses are performed at rest and after one hour exercise on a treadmill. Acylcarnitines in muscle as well as lipid and glycogen content in muscle and liver are quantified. Expression of genes involved in lipogenesis is measured by Real-Time-PCR. RESULTS At rest, VLCAD KO mice develop no clinical phenotype with all three diets, but importantly VLCAD KO mice cannot perform one hour exercise as compared to WT, this is especially apparent in mice with a fat-reduced diet. Moreover, changes in dietary fat content induce a significant increase in muscular long-chain acylcarnitines and hepatic lipid content in VLCAD KO mice after exercise. A fat-reduced diet up-regulates hepatic lipogenesis at rest. At the same time, muscular glycogen is significantly lower than in WT. CONCLUSIONS We here demonstrate that a fat-reduced and carbohydrate-enriched diet does not prevent the myopathic phenotype in VLCAD KO mice. An increase in dietary fat is safe at rest with respect to the muscle but results in a significant muscular acylcarnitine increase after exercise.
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Affiliation(s)
- Sonja Primassin
- Department of General Pediatrics, University Children's Hospital, Duesseldorf, Germany.
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32
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Tucci S, Flögel U, Sturm M, Borsch E, Spiekerkoetter U. Disrupted fat distribution and composition due to medium-chain triglycerides in mice with a β-oxidation defect. Am J Clin Nutr 2011; 94:439-49. [PMID: 21697078 DOI: 10.3945/ajcn.111.012948] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Because of the enhanced recognition of inherited long-chain fatty acid oxidation disorders by worldwide newborn screening programs, an increasing number of asymptomatic patients receive medium-chain triglyceride (MCT) supplements to prevent the development of cardiomyopathy and myopathy. OBJECTIVE MCT supplementation has been recognized as a safe dietary intervention, but long-term observations into later adulthood are still not available. We investigated the consequences of a prolonged MCT diet on abdominal fat distribution and composition and on liver fat. DESIGN Mice with very-long-chain acyl-coenzyme A dehydrogenase deficiency (VLCAD(-/-)) were supplemented for 1 y with a diet in which MCTs replaced long-chain triglycerides without increasing the total fat content. The dietary effects on abdominal fat accumulation and composition were analyzed by in vivo (1)H- and (13)C-magnetic resonance spectroscopy (9.4 Tesla). RESULTS After 1 y of MCT supplementation, VLCAD(-/-) mice accumulated massive visceral fat and had a dramatic increase in the concentration of serum free fatty acids. Furthermore, we observed a profound shift in body triglyceride composition, ie, concentrations of physiologically important polyunsaturated fatty acids dramatically decreased. (1)H-Magnetic resonance spectroscopy analysis and histologic evaluation of the liver also showed pronounced fat accumulation and marked oxidative stress. CONCLUSION Although the MCT-supplemented diet has been reported to prevent the development of cardiomyopathy and skeletal myopathy in fatty acid oxidation disorders, our data show that long-term MCT supplementation results in a severe clinical phenotype similar to that of nonalcoholic steatohepatitis and the metabolic syndrome.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, University Children's Hospital, Düsseldorf, Germany.
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33
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Hooper AJ, Adams LA, Burnett JR. Genetic determinants of hepatic steatosis in man. J Lipid Res 2011; 52:593-617. [PMID: 21245030 DOI: 10.1194/jlr.r008896] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Hepatic steatosis is one of the most common liver disorders in the general population. The main cause of hepatic steatosis is nonalcoholic fatty liver disease (NAFLD), representing the hepatic component of the metabolic syndrome, which is characterized by type 2 diabetes, obesity, and dyslipidemia. Insulin resistance and excess adiposity are considered to play key roles in the pathogenesis of NAFLD. Although the risk factors for NAFLD are well established, the genetic basis of hepatic steatosis is largely unknown. Here we review recent progress on genomic variants and their association with hepatic steatosis and discuss the potential impact of these genetic studies on clinical practice. Identifying the genetic determinants of hepatic steatosis will lead to a better understanding of the pathogenesis and progression of NAFLD.
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Affiliation(s)
- Amanda J Hooper
- Department of Core Clinical Pathology and Biochemistry, Royal Perth Hospital, Perth, Australia
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34
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Goetzman ES. Modeling Disorders of Fatty Acid Metabolism in the Mouse. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 100:389-417. [DOI: 10.1016/b978-0-12-384878-9.00010-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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35
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Tucci S, Primassin S, Spiekerkoetter U. Fasting-induced oxidative stress in very long chain acyl-CoA dehydrogenase-deficient mice. FEBS J 2010; 277:4699-708. [PMID: 20883455 DOI: 10.1111/j.1742-4658.2010.07876.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hepatopathy and hepatomegaly as consequences of prolonged fasting or illnesses are typical clinical features of very long chain acyl-CoA dehydrogenase (VLCACD) deficiency, the most common long-chain fatty acid β-oxidation defect. Supplementation with medium-chain triglycerides (MCTs) is an important treatment measure in these defects, in order to supply sufficient energy. Little is known about the pathogenetic mechanisms leading to hepatopathy. Here, we investigated the effects of prolonged fasting and an MCT diet on liver function. Wild-type (WT) and VLCAD knockout mice were fed with either a regular long-chain triglyceride diet or an MCT diet for 5 weeks. In both groups, we determined liver and blood lipid contents under nonfasting conditions and after 24 h of fasting. Expression of genes regulating peroxisomal and microsomal oxidation pathways was analyzed by RT-PCR. In addition, glutathione peroxidase and catalase activities, as well as thiobarbituric acid reactive substances, were examined. In VLCAD knockout mice fed with a long-chain triglyceride diet, fasting is associated with excessive accumulation of liver lipids, resulting in hepatopathy and strong upregulation of peroxisomal and microsomal oxidation pathways as well as antioxidant enzyme activities and thiobarbituric acid reactive substances. These effects were even evident in nonfasted mice fed with an MCT diet, and were particularly pronounced in fasted mice fed with an MCT diet. This study strongly suggests that liver damage in fatty acid oxidation defects is attributable to oxidative stress and generation of reactive oxygen species as a result of significant fat accumulation. An MCT diet does not prevent hepatic damage during catabolism and metabolic derangement.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, University Children's Hospital, Duesseldorf, Germany.
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