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Ranea-Robles P, Pavlova NN, Bender A, Pereyra AS, Ellis JM, Stauffer B, Yu C, Thompson CB, Argmann C, Puchowicz M, Houten SM. A mitochondrial long-chain fatty acid oxidation defect leads to transfer RNA uncharging and activation of the integrated stress response in the mouse heart. Cardiovasc Res 2022; 118:3198-3210. [PMID: 35388887 PMCID: PMC9799058 DOI: 10.1093/cvr/cvac050] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 03/08/2022] [Accepted: 03/23/2022] [Indexed: 01/25/2023] Open
Abstract
AIMS Cardiomyopathy and arrhythmias can be severe presentations in patients with inherited defects of mitochondrial long-chain fatty acid β-oxidation (FAO). The pathophysiological mechanisms that underlie these cardiac abnormalities remain largely unknown. We investigated the molecular adaptations to a FAO deficiency in the heart using the long-chain acyl-CoA dehydrogenase (LCAD) knockout (KO) mouse model. METHODS AND RESULTS We observed enrichment of amino acid metabolic pathways and of ATF4 target genes among the upregulated genes in the LCAD KO heart transcriptome. We also found a prominent activation of the eIF2α/ATF4 axis at the protein level that was independent of the feeding status, in addition to a reduction of cardiac protein synthesis during a short period of food withdrawal. These findings are consistent with an activation of the integrated stress response (ISR) in the LCAD KO mouse heart. Notably, charging of several transfer RNAs (tRNAs), such as tRNAGln was decreased in LCAD KO hearts, reflecting a reduced availability of cardiac amino acids, in particular, glutamine. We replicated the activation of the ISR in the hearts of mice with muscle-specific deletion of carnitine palmitoyltransferase 2. CONCLUSIONS Our results show that perturbations in amino acid metabolism caused by long-chain FAO deficiency impact cardiac metabolic signalling, in particular the ISR. These results may serve as a foundation for investigating the role of the ISR in the cardiac pathology associated with long-chain FAO defects.Translational Perspective: The heart relies mainly on mitochondrial fatty acid β-oxidation (FAO) for its high energy requirements. The heart disease observed in patients with a genetic defect in this pathway highlights the importance of FAO for cardiac health. We show that the consequences of a FAO defect extend beyond cardiac energy homeostasis and include amino acid metabolism and associated signalling pathways such as the integrated stress response.
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Affiliation(s)
- Pablo Ranea-Robles
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
| | - Natalya N Pavlova
- Cancer Biology & Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Aaron Bender
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
| | - Andrea S Pereyra
- Brody School of Medicine at East Carolina University, Department of Physiology, and East Carolina Diabetes and Obesity Institute, Greenville, NC 27858, USA
| | - Jessica M Ellis
- Brody School of Medicine at East Carolina University, Department of Physiology, and East Carolina Diabetes and Obesity Institute, Greenville, NC 27858, USA
| | - Brandon Stauffer
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
- Mount Sinai Genomics, Inc, Stamford, CT 06902, USA
| | - Chunli Yu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
- Mount Sinai Genomics, Inc, Stamford, CT 06902, USA
| | - Craig B Thompson
- Cancer Biology & Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Carmen Argmann
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
| | - Michelle Puchowicz
- Department of Nutrition, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Sander M Houten
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, Box 1498, New York, NY 10029, USA
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Ezzeddini R, Taghikhani M, Salek Farrokhi A, Somi MH, Samadi N, Esfahani A, Rasaee MJ. Downregulation of fatty acid oxidation by involvement of HIF-1α and PPARγ in human gastric adenocarcinoma and related clinical significance. J Physiol Biochem 2021; 77:249-260. [PMID: 33730333 DOI: 10.1007/s13105-021-00791-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 01/19/2021] [Indexed: 12/18/2022]
Abstract
Lipid metabolism rewiring in gastric adenocarcinoma (GA) pathogenesis is still not clearly elucidated. This study aimed to describe the role of lipid catabolism in GA patient outcomes and possible therapeutic targets by analyzing the effect of hypoxia-inducible factor-1α (HIF-1α) on fatty acid oxidation (FAO). AGS cell line was cultured in normoxic and hypoxic conditions, and FAO-related genes were analyzed by real-time-PCR and Western-blot. The study group comprised 108 newly diagnosed GA patients and 152 control cases. Serum concentrations of medium and long-chain acyl-CoA dehydrogenases (MCAD and LCAD) proteins were measured using ELISA, and local expression of HIF-1α, carnitine palmitoyl transferase 1 (CPT1A) and peroxisome proliferator-activated receptor γ (PPARγ) was evaluated by immunohistochemistry. In addition, gene expression of PPARγ, CPT1A, LCAD, and MCAD was assessed by real-time-PCR. In vitro findings indicate HIF-1α upregulation and FAO-related genes and proteins reduction in the hypoxic culture of AGS cells. GA patients had significantly lower circulating levels of LCAD compared to controls. Higher protein expression of HIF-1α and downregulated CPT1A and PPARγ were observed in GA tissues versus controls. Gene expression of CPT1A, PPARγ, LCAD, and MCAD were repressed in GA tissues compared to controls. Moreover, reduced expression of CPT1A, PPARγ, and MCAD were correlated with HIF-1α upregulation in GA. Poor patient outcome was associated with lower PPARγ and LCAD expression in GA. HIF-1α upregulation in human GA patients and AGS cells was paralleled by downregulation of lipid catabolism genes potentially via reduced PPARγ-mediated FAO. This metabolic adaptation to hypoxic condition may play a role in GA pathogenesis and might have clinical and therapeutic value in GA patients.
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Affiliation(s)
- Rana Ezzeddini
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University, Jalal AleAhmad Highway, Nasr, P.O.Box: 14115-331, Tehran, Iran
| | - Mohammad Taghikhani
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
- Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University, Jalal AleAhmad Highway, Nasr, P.O.Box: 14115-331, Tehran, Iran.
| | - Amir Salek Farrokhi
- Department of Immunology, School of Medicine, Semnan University of Medical Sciences, Semnan, Iran
| | - Mohammad Hossein Somi
- Liver and Gastrointestinal Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nasser Samadi
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Biochemistry, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Esfahani
- Hematology and Oncology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Javad Rasaee
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Jalal AleAhmad Highway, Nasr, P.O.Box: 14115-331, Tehran, Iran.
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Lv T, Zhu S, Ma Y, Feng H, Wan Q. Immunoprecipitation of Acetyl-lysine And Western Blotting of Long-chain acyl-CoA Dehydrogenases and Beta-hydroxyacyl-CoA Dehydrogenase in Palmitic Acid Treated Human Renal Tubular Epithelial Cells. Bio Protoc 2020; 10:e3765. [PMID: 33659423 DOI: 10.21769/bioprotoc.3765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/26/2020] [Accepted: 07/27/2020] [Indexed: 11/02/2022] Open
Abstract
As one of the main energy metabolism organs, kidney has been proved to have high energy requirements and are more inclined to fatty acid metabolism as the main energy source. Long-chain acyl-CoA dehydrogenases (LCAD) and beta-hydroxyacyl-CoA dehydrogenase (beta-HAD), key enzymes involved in fatty acid oxidation, has been identified as the substrate of acetyltransferase GCN5L1 and deacetylase Sirt3. Acetylation levels of LCAD and beta-HAD regulate its enzymes activity and thus affect fatty acid oxidation rate. Moreover, immunoprecipitation is a key assay for the detection of LCAD and beta-HAD acetylation levels. Here we describe a protocol of immunoprecipitation of acetyl-lysine and western blotting of LCAD and beta-HAD in palmitic acid treated HK-2 cells (human renal tubular epithelial cells). The scheme provides the readers with clear steps so that this method could be applied to detect the acetylation level of various proteins.
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Affiliation(s)
- Tingting Lv
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250021, China
| | - Suwei Zhu
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250021, China
| | - Yuan Ma
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250021, China
| | - Hong Feng
- Cancer Center, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, 250021, China
| | - Qiang Wan
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250021, China.,Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, 250021, China
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Xu X, Zhu XP, Bai JY, Xia P, Li Y, Lu Y, Li XY, Gao X. Berberine alleviates nonalcoholic fatty liver induced by a high-fat diet in mice by activating SIRT3. FASEB J 2019; 33:7289-7300. [PMID: 30848932 DOI: 10.1096/fj.201802316r] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Berberine (BBR) shows promising effects in the treatment of nonalcoholic fatty liver disease (NAFLD) by influencing various metabolic aspects. Inhibition of mitochondrial β-oxidation (β-OX) participates in the pathogenesis of NAFLD. Silent mating-type information regulation 2 homolog 3 (SIRT3) has been reported to regulate mitochondrial β-OX by deacetylating its substrate, long-chain acyl-coenzyme A dehydrogenase (LCAD). This study aimed to explore whether BBR can promote mitochondrial β-OX and the role of SIRT3 as well as the mechanisms underlying the effects of BBR on hepatic lipid metabolism in mice fed a high-fat diet (HFD). BBR can significantly improve systematic and hepatic lipid metabolism in HFD-fed mice. Metabolomics analysis revealed that β-OX was inhibited in HFD-induced mice, as indicated by the reduced production of short and medium carbon chain acyl-carnitines, the activated form of free fatty acids, via β-OX, which was reversed by BBR intervention. Exploration of the mechanism found that BBR intervention reversed the down-regulation of SIRT3 and decreased the LCAD hyperacetylation level in HFD-fed mice. SIRT3 knockout (KO) mice were used to identify the role of SIRT3 in the BBR's influence of β-OX. The beneficial effects of BBR on systemic and hepatic metabolism were profoundly attenuated in KO mice. Moreover, the promotive effect of BBR on β-OX in HFD-induced mice was partially abolished in KO mice. These results suggested that BBR alleviates HFD-induced inhibition of fatty acid β-OX partly through SIRT3-mediated LCAD deacetylation, which may provide a novel mechanism and support BBR as a promising therapeutic for NAFLD.-Xu, X., Zhu, X.-P., Bai, J.-Y., Xia, P., Li, Y., Lu, Y., Li, X.-Y., Gao, X. Berberine alleviates nonalcoholic fatty liver induced by a high-fat diet in mice by activating SIRT3.
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Affiliation(s)
- Xi Xu
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China
| | - Xiao-Peng Zhu
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China
| | - Jin-Yun Bai
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China
| | - Pu Xia
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China.,Fudan Institute for Metabolic Diseases, Shanghai, China; and
| | - Yu Li
- Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Yan Lu
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China.,Fudan Institute for Metabolic Diseases, Shanghai, China; and
| | - Xiao-Ying Li
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China.,Fudan Institute for Metabolic Diseases, Shanghai, China; and
| | - Xin Gao
- Department of Endocrinology and Metabolism, Affiliated Zhongshan Hospital of Fudan University, Shanghai, China.,Fudan Institute for Metabolic Diseases, Shanghai, China; and
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Nakamura MT, Yudell BE, Loor JJ. Regulation of energy metabolism by long-chain fatty acids. Prog Lipid Res 2013; 53:124-44. [PMID: 24362249 DOI: 10.1016/j.plipres.2013.12.001] [Citation(s) in RCA: 467] [Impact Index Per Article: 42.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 12/03/2013] [Accepted: 12/04/2013] [Indexed: 12/12/2022]
Abstract
In mammals, excess energy is stored primarily as triglycerides, which are mobilized when energy demands arise. This review mainly focuses on the role of long chain fatty acids (LCFAs) in regulating energy metabolism as ligands of peroxisome proliferator-activated receptors (PPARs). PPAR-alpha expressed primarily in liver is essential for metabolic adaptation to starvation by inducing genes for beta-oxidation and ketogenesis and by downregulating energy expenditure through fibroblast growth factor 21. PPAR-delta is highly expressed in skeletal muscle and induces genes for LCFA oxidation during fasting and endurance exercise. PPAR-delta also regulates glucose metabolism and mitochondrial biogenesis by inducing FOXO1 and PGC1-alpha. Genes targeted by PPAR-gamma in adipocytes suggest that PPAR-gamma senses incoming non-esterified LCFAs and induces the pathways to store LCFAs as triglycerides. Adiponectin, another important target of PPAR-gamma may act as a spacer between adipocytes to maintain their metabolic activity and insulin sensitivity. Another topic of this review is effects of skin LCFAs on energy metabolism. Specific LCFAs are required for the synthesis of skin lipids, which are essential for water barrier and thermal insulation functions of the skin. Disturbance of skin lipid metabolism often causes apparent resistance to developing obesity at the expense of normal skin function.
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Affiliation(s)
- Manabu T Nakamura
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL 61801, USA.
| | - Barbara E Yudell
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL 61801, USA
| | - Juan J Loor
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL 61801, USA
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Ribas GS, Vargas CR, Wajner M. L-carnitine supplementation as a potential antioxidant therapy for inherited neurometabolic disorders. Gene 2013; 533:469-76. [PMID: 24148561 DOI: 10.1016/j.gene.2013.10.017] [Citation(s) in RCA: 154] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 10/02/2013] [Accepted: 10/09/2013] [Indexed: 01/11/2023]
Abstract
In recent years increasing evidence has emerged suggesting that oxidative stress is involved in the pathophysiology of a number of inherited metabolic disorders. However the clinical use of classical antioxidants in these diseases has been poorly evaluated and so far no benefit has been demonstrated. l-Carnitine is an endogenous substance that acts as a carrier for fatty acids across the inner mitochondrial membrane necessary for subsequent beta-oxidation and ATP production. Besides its important role in the metabolism of lipids, l-carnitine is also a potent antioxidant (free radical scavenger) and thus may protect tissues from oxidative damage. This review addresses recent findings obtained from patients with some inherited neurometabolic diseases showing that l-carnitine may be involved in the reduction of oxidative damage observed in these disorders. For some of these diseases, reduced concentrations of l-carnitine may occur due to the combination of this compound to the accumulating toxic metabolites, especially organic acids, or as a result of protein restricted diets. Thus, l-carnitine supplementation may be useful not only to prevent tissue deficiency of this element, but also to avoid oxidative damage secondary to increased production of reactive species in these diseases. Considering the ability of l-carnitine to easily cross the blood-brain barrier, l-carnitine supplementation may also be beneficial in preventing neurological damage derived from oxidative injury. However further studies are required to better explore this potential.
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Affiliation(s)
- Graziela S Ribas
- Federal University of Rio Grande do Sul, Brazil; Serviço de Genética Médica, HCPA, Ramiro Barcelos 2350, Porto Alegre, RS 90035-903, Brazil
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Shearn CT, Smathers RL, Jiang H, Orlicky DJ, Maclean KN, Petersen DR. Increased dietary fat contributes to dysregulation of the LKB1/AMPK pathway and increased damage in a mouse model of early-stage ethanol-mediated steatosis. J Nutr Biochem 2013; 24:1436-45. [PMID: 23465594 DOI: 10.1016/j.jnutbio.2012.12.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 11/30/2012] [Accepted: 12/06/2012] [Indexed: 12/22/2022]
Abstract
OBJECTIVE The objective of the study was to examine the interaction of moderate and high dietary fat and ethanol with respect to formation of steatosis and regulation of the AMP-activated protein kinase (AMPK) pathway in a mouse model of chronic ethanol consumption. METHODS Male C57BL/6J mice were pair-fed a modified Lieber-DeCarli diet composed of either moderate fat [30% fat-derived calories (MF)] or high fat [45% fat-derived calories (HF)] combined with increasing concentrations of ethanol (2%-6%) for 6 weeks. RESULTS Chronic ethanol consumption resulted in significant increases in plasma alanine aminotransferase in MF (1.84-fold) and HF mice (2.33-fold), yet liver triglycerides only increased significantly in the HF model (1.62-fold). Ethanol addition significantly increased plasma adiponectin under conditions of MF but not HF. In combination with MF, the addition of ethanol significantly decreased total and hepatic pThr(172)AMPKα and acetyl CoA Carboxylase (ACC). HF plus ethanol decreased pSer(108)AMPKβ, yet a marked 1.5-fold increase in pThr(172)AMPKα occurred. No change was evident in pSer(79)ACC under conditions of ethanol and HF ingestion. In both models, nuclear levels of sterol response element binding protein 1c and carbohydrate response element binding protein were decreased. Surprisingly, MF plus ethanol significantly elevated protein expression of medium-chain acyl-CoA dehydrogenase (MCAD), long-chain acyl-CoA dehydrogenase (LCAD) and very long chain acyl-CoA dehydrogenase but did not significantly affect mRNA expression of other proteins involved in β-oxidation and fatty acid synthesis. HF plus ethanol significantly reduced mRNA expression of both stearoyl CoA desaturase 1 and fatty acid elongase 5, but did not have an effect on MCAD or LCAD. CONCLUSION These data suggest that, when co-ingested with ethanol, dietary fat differentially contributes to dysregulation of adiponectin-dependent activation of the AMPK pathway in the liver of mice.
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Henriksen BS, Curtis ME, Fillmore N, Cardon BR, Thomson DM, Hancock CR. The effects of chronic AMPK activation on hepatic triglyceride accumulation and glycerol 3-phosphate acyltransferase activity with high fat feeding. Diabetol Metab Syndr 2013; 5:29. [PMID: 23725555 PMCID: PMC3679947 DOI: 10.1186/1758-5996-5-29] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 05/18/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND High fat feeding increases hepatic fat accumulation and is associated with hepatic insulin resistance. AMP Activated Protein Kinase (AMPK) is thought to inhibit lipid synthesis by the acute inhibition of glycerol-3-phosphate acyltransferase (GPAT) activity and transcriptional regulation via sterol regulatory element binding protein-1c (SREBP-1c). METHODS The purpose of this study was to determine if chronic activation of AMPK prevented an increase in GPAT1 activity in rats fed a high fat diet. Rats were fed a control (C), or a high fat (HF) diet (60% fat) for 6 weeks and injected with saline or a daily aminoimidazole carboxamide ribnucleotide (AICAR) dose of 0.5 mg/g body weight. RESULTS Chronic AMPK activation by AICAR injections resulted in a significant reduction in hepatic triglyceride accumulation in both the C and HF fed animals (C, 5.5±0.7; C+AICAR, 2.7 ±0.3; HF, 21.8±3.3; and HF+AICAR, 8.0±1.8 mg/g liver). HF feeding caused an increase in total GPAT and GPAT1 activity, which was not affected by chronic AMPK activation (GPAT1 activity vs. C, C+AICAR, 92±19%; HF, 186±43%; HF+AICAR, 234±62%). Markers of oxidative capacity, including citrate synthase activity and cytochrome c abundance, were not affected by chronic AICAR treatment. Interestingly, HF feeding caused a significant increase in long chain acyl-CoA dehydrogenase or LCAD (up 66% from C), a marker of fatty acid oxidation capacity. CONCLUSIONS These results suggest that chronic AMPK activation limits hepatic triglyceride accumulation independent of a reduction in total GPAT1 activity.
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Affiliation(s)
- Bradley S Henriksen
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Mary E Curtis
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - Natasha Fillmore
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Brandon R Cardon
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
| | - David M Thomson
- Department of Physiology and Developmental Biology, Brigham Young University, Provo, UT 84602, USA
| | - Chad R Hancock
- Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, UT 84602, USA
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