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Wu XF, Liu Y, Zhan JS, Huang QL, Li WY. A novel splice variant of goat CPT1a gene and their diverse mRNA expression profiles. Anim Biotechnol 2023; 34:2571-2581. [PMID: 36047452 DOI: 10.1080/10495398.2022.2106573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The Alternative splicing (AS) of Carnitine palmitoyltransferase 1a (CPT1a) and their expression profiles had never been illuminated in goats until now. Herein, a novel splice transcript in the CPT1a gene that is predicted to result in the skipping of exons 6-19 (CPT1a-sv1) has been isolated in addition to the full-length transcript in goats. The result of RT-PCR showed that CPT1a-sv1 is 606 bp in length and consists of 6 exons. A novel exon 6 was consisted of partial exon 5 and partial exon 19, compared to that in CPT1a. RT-qPCR analysis showed that the expression patterns of CPT1a and CPT1a-sv1 are spatially different. In both kid and adult goats, the CPT1a transcript is strongly expressed in the liver, spleen, lung, kidney, and brain tissues. However, CPT1a-sv1 has a strong tissue-specific expression pattern, with moderate RNA levels in the liver and brain of kids, while highly expressed in the liver and minimally expressed in the brain of adults. We observed two transcripts to be involved in brain development. These findings improve our understanding of the function of the CPT1a gene in goats and provide information on the molecular mechanism of AS events.
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Affiliation(s)
- Xian-Feng Wu
- Institute of Animal Husbandry and Veterinary, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Yuan Liu
- Institute of Animal Husbandry and Veterinary, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Jin-Shun Zhan
- Institute of Animal Husbandry and Veterinary, Jiangxi Academy of Agricultural Sciences, Nanchang, Jiangxi, China
| | - Qin-Lou Huang
- Institute of Animal Husbandry and Veterinary, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
| | - Wen-Yang Li
- Institute of Animal Husbandry and Veterinary, Fujian Academy of Agricultural Sciences, Fuzhou, Fujian, China
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2
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He W, Gao M, Yang R, Zhao Z, Mi J, Sun H, Xiao H, Fang X. The effect of CPT1B gene on lipid metabolism and its polymorphism analysis in Chinese Simmental cattle. Anim Biotechnol 2022; 33:1428-1440. [PMID: 33827354 DOI: 10.1080/10495398.2021.1904966] [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] [Indexed: 01/09/2023]
Abstract
Carnitine palmitoyltransferase 1B (CPT1B) is a candidate gene that regulates livestock animal lipid metabolism and encodes the rate-limiting enzyme in fatty acid β-oxidation. To explore the effect of this gene on lipid metabolism in cattle, this study examined CPT1B gene polymorphism in Chinese Simmental cattle and the effect of CPT1B on lipid metabolism. The results showed that the triglyceride content increased significantly with increasing CPT1B gene expression in bovine fetal fibroblasts (BFFs) (p < 0.05), while CPT1B knockout led to decreased CPT1B expression and a downward trend in triglyceride levels. Correlation analysis showed a significant association between the g.119896238 G > C locus and Chinese Simmental cattle backfat thickness (p < 0.05). Backfat thickness was significantly greater in individuals with the GC genotype (0.93 ± 0.67 cm) than in those with the CC genotype (0.84 ± 0.60 cm). The g.119889302 T > C locus was significantly correlated with arachidonic acid content in Chinese Simmental cattle (p < 0.05). The arachidonic acid content in the longissimus muscle was significantly higher in CC genotype beef cattle (0.054 g/100 g) than in those with the other two genotypes (0.046 g/100 g, 0.049 g/100 g). These molecular markers can be effectively used for marker-assisted selection in cattle breeding.
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Affiliation(s)
- Wei He
- College of Animal Sciences, Jilin University, Changchun, China
| | - Ming Gao
- College of Animal Sciences, Jilin University, Changchun, China
| | - Runjun Yang
- College of Animal Sciences, Jilin University, Changchun, China
| | - Zhihui Zhao
- College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, China
| | - Jiaqi Mi
- College of Animal Sciences, Jilin University, Changchun, China
| | - Hao Sun
- College of Animal Sciences, Jilin University, Changchun, China
| | - Hang Xiao
- College of Animal Sciences, Jilin University, Changchun, China
| | - Xibi Fang
- College of Animal Sciences, Jilin University, Changchun, China
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3
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Ghanem N, Zayed M, Mohamed I, Mohammady M, Shehata MF. Co-expression of candidate genes regulating growth performance and carcass traits of Barki lambs in Egypt. Trop Anim Health Prod 2022; 54:260. [PMID: 35953554 PMCID: PMC9372007 DOI: 10.1007/s11250-022-03263-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 07/29/2022] [Indexed: 12/02/2022]
Abstract
Sheep are considered one of the main sources of animal protein in Egypt and the producers of sheep mutton eagers to find biological criteria for selecting fast-growing lambs that reach market weight early. Therefore, the present study aimed to find a link between the expression profile of selected candidate genes with growth performance and carcass traits of Barki lambs. Thirty-eight Barki lambs were kept and fed individually after weaning till 12 months of age and were divided into 3 groups according to growth performance (fast, intermediate, and slow-growing). Three samples were taken from different body tissues (eye muscle, liver, and fat tail) of each group, directly during slaughtering and stored at − 80 °C until RNA isolation. Real-time PCR was used to profile selected candidate genes (RPL7, CTP1, FABP4, ADIPOQ, and CAPN3) and GAPDH was used as a housekeeping gene. The results indicated that the final body weight was significantly (P ≤ 0.05) greater in the fast (49.9 kg) and intermediate (40.7 kg) compared to slow-growing animals (30.8 kg). The hot carcass weight was heavier (P ≤ 0.05) in the fast and intermediate-growing (24.57 and 19.07 kg) than slow-growing lambs (15.10 kg). The blood profiles of T3 and T4 hormones in addition to other parameters such as total protein, total lipids, and calcium level showed no clear variations among different experimental groups. At the molecular level, our data demonstrated upregulation of genes involved in protein biosynthesis (RPL7), fatty acid oxidation (CPT1), and lipolysis (FABP4) in the fast and intermediate-growing lambs in all studied tissues which facilitate protein accretion, energy expenditure, and fatty acid partitioning required for muscle building up. Moreover, the expression profile of the gene involved in muscle development (CAPN3) was increased in fast and intermediate-growing compared to slow-growing lambs in order to support muscle proper development. On the other hand, a candidate gene involved in lipogenesis (ADIPOQ) was expressed similarly in fat and liver tissues; however, its expression was increased in muscles of fast and intermediate-growing lambs compared to slow-growing animals. In conclusion, the current study indicated that the expression profile of genes involved in metabolic activities of liver, muscle, and adipose tissue is linked with the growth performance of lambs although no variations were detected in blood parameters. This provides an evidence for the importance of co-expression of these genes in body tissues to determine the final body weight and carcass characteristics of Barki sheep.
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Affiliation(s)
- Nasser Ghanem
- Department of Animal Production, Faculty of Agriculture, Cairo University, El-Gamaa Street, Giza, 12613, Egypt. .,Faculty of Agriculture, Cairo University Research Park, Cairo University, Cairo, Egypt.
| | - Mohamed Zayed
- Department of Animal and Poultry Breeding, Animal and Poultry Division, Desert Research Center, Cairo, Egypt
| | - Ismail Mohamed
- Department of Animal and Poultry Breeding, Animal and Poultry Division, Desert Research Center, Cairo, Egypt
| | - Mona Mohammady
- Department of Animal and Poultry Breeding, Animal and Poultry Division, Desert Research Center, Cairo, Egypt
| | - M F Shehata
- Department of Animal and Poultry Breeding, Animal and Poultry Division, Desert Research Center, Cairo, Egypt
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4
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The Impact of Moderate-Intensity Continuous or High-Intensity Interval Training on Adipogenesis and Browning of Subcutaneous Adipose Tissue in Obese Male Rats. Nutrients 2020; 12:nu12040925. [PMID: 32230849 PMCID: PMC7231004 DOI: 10.3390/nu12040925] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/18/2020] [Accepted: 03/24/2020] [Indexed: 01/12/2023] Open
Abstract
This study compares the effect of two types of exercise training, i.e., moderate-intensity continuous training (MICT) or high-intensity interval training (HIIT) on the browning of subcutaneous white adipose tissue (scWAT) in obese male rats. Effects on fat composition, metabolites, and molecular markers of differentiation and energy expenditure were examined. Forty male Wistar rats were assigned to lean (n = 8) or obese (n = 32) groups and fed either a standard chow or high-fat obesogenic diet for 10 weeks. Eight lean and obese rats were then blood and tissue sampled, and the remaining obese animals were randomly allocated into sedentary, MICT, or HIIT (running on a treadmill 5 days/week) groups that were maintained for 12 weeks. Obesity increased plasma glucose and insulin and decreased irisin and FGF-21. In scWAT, this was accompanied with raised protein abundance of markers of adipocyte differentiation, i.e., C/EBP-α, C/EBP-β, and PPAR-γ, whereas brown fat-related genes, i.e., PRDM-16, AMPK/SIRT1/PGC-1α, were reduced as was UCP1 and markers of fatty acid transport, i.e., CD36 and CPT1. Exercise training increased protein expression of brown fat-related markers, i.e., PRDM-16, AMPK/SIRT1/PGC-1α, and UCP1, together with gene expression of fatty acid transport, i.e., CD36 and CPT1, but decreased markers of adipocyte differentiation, i.e., C/EBP-α, C/EBP-β, and plasma glucose. The majority of these adaptations were greater with HIIT compared to MICT. Our findings indicate that prolonged exercise training promotes the browning of white adipocytes, possibly through suppression of adipogenesis together with white to beige trans-differentiation and is dependent on the intensity of exercise.
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Kizaki K, Kageyama T, Toji N, Koshi K, Sasaki K, Yamagishi N, Ishiguro-Oonuma T, Takahashi T, Hashizume K. Gene expression profiles in bovine granulocytes reflect the aberration of liver functions. Anim Sci J 2019; 91:e13324. [PMID: 31863537 DOI: 10.1111/asj.13324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Revised: 09/16/2019] [Accepted: 11/15/2019] [Indexed: 11/26/2022]
Abstract
Liver performs several important functions; however, predicting its functions is difficult. Methods of analyzing gene expression profiles, for example, microarray, provide functional information of tissues. Liver and peripheral blood leukocytes (PBLs) were collected from Holstein cows subjected to two different physiological conditions (non-pregnant and pregnant), and PBLs were fractionated by gradient cell separation. RNA from PBLs and liver were applied to oligo-DNA microarray and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). It revealed a group of stable bovine liver genes under constant physiological conditions. When they applied to physiological conditions including non-pregnant and pregnant, the profiles of some genes in liver were consistent with those in PBLs. Microarray data subjected to a principal component analysis (PCA) showed that the hepatic gene expression profiles were more consistent with those of granulocytes than mononuclear cells. The relationship of gene profiles in liver with granulocytes was confirmed by RT-qPCR and hierarchical cluster analysis. Gene profiles of granulocytes were more reliable than those of mononuclear cells, which reflected liver functions. These results suggest that the genes expressed in PBLs, particularly granulocytes, may be convenient bioindicators for the diagnosis of clinical disorder and/or detecting aberration of liver functions in cows subjected to different physiological conditions.
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Affiliation(s)
- Keiichiro Kizaki
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Tomomi Kageyama
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan
| | - Noriyuki Toji
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Katsuo Koshi
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan
| | - Kouya Sasaki
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Norio Yamagishi
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Toshina Ishiguro-Oonuma
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Toru Takahashi
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan.,United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Kazuyoshi Hashizume
- Cooperative Department of Veterinary Medicine, Iwate University, Morioka, Japan
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van der Hoek MD, Madsen O, Keijer J, van der Leij FR. Evolutionary analysis of the carnitine- and choline acyltransferases suggests distinct evolution of CPT2 versus CPT1 and related variants. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:909-918. [PMID: 29730527 DOI: 10.1016/j.bbalip.2018.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/24/2018] [Accepted: 05/03/2018] [Indexed: 10/17/2022]
Abstract
Carnitine/choline acyltransferases play diverse roles in energy metabolism and neuronal signalling. Our knowledge of their evolutionary relationships, important for functional understanding, is incomplete. Therefore, we aimed to determine the evolutionary relationships of these eukaryotic transferases. We performed extensive phylogenetic and intron position analyses. We found that mammalian intramitochondrial CPT2 is most closely related to cytosolic yeast carnitine transferases (Sc-YAT1 and 2), whereas the other members of the family are related to intraorganellar yeast Sc-CAT2. Therefore, the cytosolically active CPT1 more closely resembles intramitochondrial ancestors than CPT2. The choline acetyltransferase is closely related to carnitine acetyltransferase and shows lower evolutionary rates than long chain acyltransferases. In the CPT1 family several duplications occurred during animal radiation, leading to the isoforms CPT1A, CPT1B and CPT1C. In addition, we found five CPT1-like genes in Caenorhabditis elegans that strongly group to the CPT1 family. The long branch leading to mammalian brain isoform CPT1C suggests that either strong positive or relaxed evolution has taken place on this node. The presented evolutionary delineation of carnitine/choline acyltransferases adds to current knowledge on their functions and provides tangible leads for further experimental research.
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Affiliation(s)
- Marjanne D van der Hoek
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, P.O. box 1528, 8901BV Leeuwarden, The Netherlands; Human and Animal Physiology, Wageningen University, P.O. box 338, 6700AH Wageningen, The Netherlands
| | - Ole Madsen
- Animal Breeding and Genomics Centre, Wageningen University, P.O. box 338, 6700AH Wageningen, The Netherlands
| | - Jaap Keijer
- Human and Animal Physiology, Wageningen University, P.O. box 338, 6700AH Wageningen, The Netherlands
| | - Feike R van der Leij
- Applied Research Centre Food and Dairy, Van Hall Larenstein University of Applied Sciences, P.O. box 1528, 8901BV Leeuwarden, The Netherlands.
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7
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Schäff C, Börner S, Hacke S, Kautzsch U, Sauerwein H, Spachmann S, Schweigel-Röntgen M, Hammon H, Kuhla B. Increased muscle fatty acid oxidation in dairy cows with intensive body fat mobilization during early lactation. J Dairy Sci 2013; 96:6449-60. [DOI: 10.3168/jds.2013-6812] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 06/14/2013] [Indexed: 02/05/2023]
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8
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Tang Z, Sun C, Yan A, Wu S, Qin C, Zhang Y, Li W. Genes involved in fatty acid metabolism: molecular characterization and hypothalamic mRNA response to energy status and neuropeptide Y treatment in the orange-spotted grouper Epinephelus coioides. Mol Cell Endocrinol 2013; 376:114-24. [PMID: 23806557 DOI: 10.1016/j.mce.2013.06.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 06/12/2013] [Accepted: 06/15/2013] [Indexed: 12/19/2022]
Abstract
As in mammals, fatty acid (FA) metabolism plays diverse and vital roles in regulating food intake in fish. Multiple lines of evidence suggest that the effect of FA metabolism on food intake is linked to changes in the level of neuropeptide Y (NPY) in the hypothalamus of the rainbow trout. In mammals, the evidence suggests that FA metabolism regulates feeding via hypothalamic NPY. NPY is therefore considered an important factor that mediates the modulation of food intake by FA metabolism in vertebrates. The stimulatory effect of NPY on food intake is well known. However, to the best of our knowledge, the effect of NPY on FA metabolism in the hypothalamus has not been examined. In this study, we cloned the cDNA of four key enzymes involved in FA metabolism and assessed the effect of energy status and NPY on their mRNA expression in the hypothalamus of grouper. The full-length cDNAs of UCP2 and CPT1a and the partial coding sequence (CDS) of ACC1 and FAS were isolated from the grouper hypothalamus. These genes are expressed in the hypothalamus and during the organogenetic stage of embryogenesis. A feeding rhythm study showed that the hypothalamic expression level of NPY and CPT1a was highly correlated with feeding rhythm. Long-term fasting was found to significantly induce the hypothalamic mRNA expression of NPY, CPT1a and UCP2. An in vitro study demonstrated that NPY strongly stimulated CPT1a and UCP2 mRNA expression in a time- and dose-dependent manner. Collectively, these results suggest that these four genes related to FA metabolism may play a role in regulating food intake in grouper and, that NPY modulates FA metabolism in the grouper hypothalamus. This study showed, for the first time in vertebrates, the effect of NPY on the gene expression of FA metabolism-related enzymes.
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Affiliation(s)
- Zhiguo Tang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China
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9
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Burns TA, Kadegowda AKG, Duckett SK, Pratt SL, Jenkins TC. Palmitoleic (16:1 cis-9) and cis-vaccenic (18:1 cis-11) acid alter lipogenesis in bovine adipocyte cultures. Lipids 2012; 47:1143-53. [PMID: 23077002 DOI: 10.1007/s11745-012-3723-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 09/17/2012] [Indexed: 12/29/2022]
Abstract
Our objectives were to: (1) confirm elongation products of palmitoleic acid (16:1 cis-9) elongation in vitro using stable isotopes and (2) evaluate if exogenous supplementation of palmitoleic acid, elongation products, or both are responsible for decreased desaturation and lipogenesis rates observed with palmitoleic acid supplementation in bovine adipocytes. Stromal vascular cultures were isolated from adipose tissue of two beef carcasses, allowed to reach confluence, held for 2 days, and differentiated with a standard hormone cocktail (day 0). On day 2, secondary differentiation media containing 1 of 4 fatty acid treatments [0 μM fatty acid (control), or 150 μM palmitic (16:0), palmitoleic, or cis-vaccenic (18:1 cis-11)] was added for 4 days. On day 6, cells were incubated with [(13)C] 16:1, [(13)C] 2, or [(13)C] 18:0 to estimate elongation, lipogenic, and desaturation rates using gas chromatography-mass spectrometry. Enrichment of [(13)C] 18:1 cis-11 confirmed 18:1 cis-11 is an elongation product of 16:1. Additionally, [(13)C] label was seen in 20:1 cis-13 and cis-9, cis-11 CLA. Synthesis of [(13)C] 16:0 from [(13)C] 2 was reduced (P < 0.05) in palmitoleic acid and cis-vaccenic acid-treated compared with control cells following 36 h incubation. By 12 h of [(13)C] 18:0 incubation, cells supplemented with palmitoleic acid had reduced (P < 0.05) [(13)C] 18:1 cis-9 compared with all other treatments. Gene expression and fatty acid results support isotopic data for lipogenesis and desaturation. Therefore, palmitoleic acid is actively elongated in vitro and its elongation product, cis-vaccenic acid, can also reduce lipogenesis. However, inhibition of desaturation can be directly attributed to palmitoleic acid and not its elongation products, 18:1 cis-11 or 20:1 cis-13.
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Affiliation(s)
- T A Burns
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634-0311, USA
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10
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Burns TA, Duckett SK, Pratt SL, Jenkins TC. Supplemental palmitoleic (C16:1 cis-9) acid reduces lipogenesis and desaturation in bovine adipocyte cultures1. J Anim Sci 2012; 90:3433-41. [DOI: 10.2527/jas.2011-4972] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- T. A. Burns
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634-0311
| | - S. K. Duckett
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634-0311
| | - S. L. Pratt
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634-0311
| | - T. C. Jenkins
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC 29634-0311
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Abstract
In modern societies, oversupply of calories leads to obesity and chronic metabolic stress, which may lead to development of disease. Oversupply of calories is often associated with elevated plasma lipid concentrations and accumulation of lipids in skeletal muscle leading to decreased insulin sensitivity. Consequently, enhanced fat oxidation might be beneficial in counteracting lipid accumulation. Exercise is the most effective way to increase fat oxidation, because it increases metabolic rate. Lipid metabolism can also be altered by dietary manipulations. Thus, a fat rich diet leads to increased potential for fat oxidation by increasing the content of several of the proteins in the fat oxidative pathway. The regulation of both exercise and diet induced lipid oxidation will be discussed in this review.
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Affiliation(s)
- B Kiens
- Molecular Physiology Group, Department of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark.
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12
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Cardiac PPARalpha Protein Expression is Constant as Alternate Nuclear Receptors and PGC-1 Coordinately Increase During the Postnatal Metabolic Transition. PPAR Res 2011; 2008:279531. [PMID: 18288283 PMCID: PMC2233871 DOI: 10.1155/2008/279531] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Accepted: 07/22/2007] [Indexed: 12/25/2022] Open
Abstract
Gene expression data obtained in mouse heart indicate that increased expression for the nuclear receptor, peroxisomal proliferator activated receptor alpha (PPARalpha), prompts the postnatal transition from predominantly carbohydrate to fatty acid oxidation preference. However, no phenotypic or proteomic data are available to confirm downstream signaling and metabolic transition in mice. We studied the hypothesis that shifts in nuclear receptor expression trigger the newborn metabolic switch in a newborn sheep. This species is well characterized with regards to developmental changes in substrate oxidative metabolism. Heart tissues from fetal (130 days gestation), newborn </=24 hours, and 30-day old lambs were evaluated for protein expression from multiple enzymes controlling oxidative metabolism as well as principal nuclear receptors and coactivators. Although muscle and liver type carnitine palmitoyl transferases I showed no significant changes to correspond to the metabolic transition, hexokinase II protein content showed a profound transient drop, and pyruvate dehydrogenase kinase steadily increased. PPARalpha showed no increases preceding or during the transition, while peroxisomal proliferator activated receptor gamma coactivator-1 (PGC-1) increased approximately 20-fold transiently in newborn heart in conjunction with significant increases in thyroid hormone receptor alpha1 and retinoid-activated receptor alpha. These data challenge the paradigm that increases in PPARalpha prompt the postnatal metabolic switch, and suggest that other nuclear receptors play a major role. As thyroid hormone (TH) modulates PGC-1 expression in sheep during development, these data further suggest that well-characterized perinatal TH surge in sheep contributes to this metabolic switch.
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13
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XU C, WANG Z, ZHANG RH, ZHANG HY, FU SX, XIA C. Effect of NEFA and Glucose Levels on CPT-I mRNA Expression and Translation in Cultured Bovine Hepatocytes. J Vet Med Sci 2011; 73:97-101. [DOI: 10.1292/jvms.10-0164] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Chuang XU
- Department of Clinical Veterinary Medicine, Animal Science and Technology College, Heilongjiang Bayi Agricultural University
| | - Zhe WANG
- Department of Clinical Veterinary Medicine, Animal and Veterinary College, Jilin University
| | - Ri-he ZHANG
- Department of Clinical Veterinary Medicine, Animal and Veterinary College, Jilin University
| | - Hong-you ZHANG
- Department of Clinical Veterinary Medicine, Animal Science and Technology College, Heilongjiang Bayi Agricultural University
| | - Shi-xin FU
- Department of Clinical Veterinary Medicine, Animal Science and Technology College, Heilongjiang Bayi Agricultural University
| | - Cheng XIA
- Department of Clinical Veterinary Medicine, Animal Science and Technology College, Heilongjiang Bayi Agricultural University
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14
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Gao Y, Zhang Y, Jiang H, Xiao S, Wang S, Ma Q, Sun G, Li F, Deng Q, Dai L, Zhao Z, Cui X, Zhang S, Liu D, Zhang J. Detection of differentially expressed genes in the longissimus dorsi of Northeastern Indigenous and Large White pigs. GENETICS AND MOLECULAR RESEARCH 2011; 10:779-91. [DOI: 10.4238/vol10-2gmr1170] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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15
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Price NT, Jackson VN, Müller J, Moffat K, Matthews KL, Orton T, Zammit VA. Alternative exon usage in the single CPT1 gene of Drosophila generates functional diversity in the kinetic properties of the enzyme: differential expression of alternatively spliced variants in Drosophila tissues. J Biol Chem 2010; 285:7857-65. [PMID: 20061394 PMCID: PMC2832936 DOI: 10.1074/jbc.m109.072892] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 01/07/2010] [Indexed: 11/06/2022] Open
Abstract
The Drosophila melanogaster genome contains only one CPT1 gene (Jackson, V. N., Cameron, J. M., Zammit, V. A., and Price, N. T. (1999) Biochem. J. 341, 483-489). We have now extended our original observation to all insect genomes that have been sequenced, suggesting that a single CPT1 gene is a universal feature of insect genomes. We hypothesized that insects may be able to generate kinetically distinct variants by alternative splicing of their single CPT1 gene. Analysis of the insect genomes revealed that (a) the single CPT1 gene in each and every insect genome contains two alternative exons and (ii) in all cases, the putative alternative splicing site occurs within a small region corresponding to 21 amino acid residues that are known to be essential for the binding of substrates and of malonyl-CoA in mammalian CPT1A. We performed PCR analyses of mRNA from different Drosophila tissues; both of the anticipated splice variants of CPT1 mRNA were found to be expressed in all of the tissues tested (both in larvae and adults), with the expression level for one of the splice variants being significantly different between flight muscle and the fat body of adult Drosophila. Heterologous expression of the full-length cDNAs corresponding to the two putative variants of Drosophila CPT1 in the yeast Pichia pastoris revealed two important differences between the properties of the two variants: (i) their affinity (K(0.5)) for one of the substrates, palmitoyl-CoA, differed by 5-fold, and (ii) the sensitivity to inhibition by malonyl-CoA at fixed, higher palmitoyl-CoA concentrations was 2-fold different and associated with different kinetics of inhibition. These data indicate that alternative splicing that specifically affects a structurally crucial region of the protein is an important mechanism through which functional diversity of CPT1 kinetics is generated from the single gene that occurs in insects.
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Affiliation(s)
| | | | | | - Kevin Moffat
- the Department of Biological Sciences, University of Warwick, Gibbett Hill Road, Coventry CV4 7AL, United Kingdom
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16
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Aires CC, IJlst L, Stet F, Prip-Buus C, de Almeida IT, Duran M, Wanders RJ, Silva MF. Inhibition of hepatic carnitine palmitoyl-transferase I (CPT IA) by valproyl-CoA as a possible mechanism of valproate-induced steatosis. Biochem Pharmacol 2010; 79:792-9. [DOI: 10.1016/j.bcp.2009.10.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 10/14/2009] [Accepted: 10/14/2009] [Indexed: 11/25/2022]
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17
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Relat J, Pujol-Vidal M, Haro D, Marrero PF. A characteristic Glu17 residue of pig carnitine palmitoyltransferase 1 is responsible for the low Km for carnitine and the low sensitivity to malonyl-CoA inhibition of the enzyme. FEBS J 2008; 276:210-8. [PMID: 19049515 DOI: 10.1111/j.1742-4658.2008.06774.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Human carnitine palmitoyltransferase 1B (CPT1B) is a highly malonyl-CoA-sensitive enzyme (IC50=0.097 microm) and has a positive determinant (residues 18-28) of malonyl-CoA inhibition. By contrast, rat carnitine palmitoyltransferase 1A is less sensitive to malonyl-CoA inhibition (IC(50)=1.9 microm), and has both a positive (residues 1-18) and a negative (residues 18-28) determinant of its inhibition. Interestingly, pig CPT1B shows a low degree of malonyl-CoA sensitivity (IC(50)=0.804 microm). Here, we examined whether any additional molecular determinants affect malonyl-CoA inhibition of CPT1B. We show that the malonyl-CoA sensitivity of CPT1B is determined by the length (either 50 or 128 residues) of the N-terminal region constructed by recombining pig and human enzymes. We also show that the N-terminal region of pig CPT1B carries a single positive determinant of malonyl-CoA sensitivity, but that this is located between residues 1 and 18 of the N-terminal segment. Importantly, we found a single amino acid variation (D17E) relevant to malonyl-CoA sensitivity. Thus, Asp17 is specifically involved, under certain assay conditions, in the high malonyl-CoA sensitivity of the human enzyme, whereas the naturally occurring variation, Glu17, is responsible for both the low malonyl-CoA sensitivity and high carnitine affinity characteristics of the pig enzyme. This is the first demonstration that a single naturally occurring amino acid variation can alter CPT1B enzymatic properties.
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Affiliation(s)
- Joana Relat
- Department of Biochemistry and Molecular Biology, School of Pharmacy and Institute of Biomedicine of Barcelona University (IBUB), Spain
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18
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Yamazaki N, Matsuo T, Kurata M, Suzuki M, Fujiwaki T, Yamaguchi S, Terada H, Shinohara Y. Substitutions of three amino acids in human heart/muscle type carnitine palmitoyltransferase I caused by single nucleotide polymorphisms. Biochem Genet 2007; 46:54-63. [PMID: 17987377 DOI: 10.1007/s10528-007-9129-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2006] [Accepted: 07/23/2007] [Indexed: 10/22/2022]
Abstract
Heart/muscle type carnitine palmitoyltransferase I (M-CPTI) catalyzes the rate-limiting step of mitochondrial long-chain fatty acid (LCFA) oxidation in muscle and adipose tissue. Three replacements of nucleotides resulting in missense mutations of I66V, S427C, and E531K were observed in the M-CPTI gene of patients showing abnormal fatty acid metabolism. These nucleotide replacements were found to be common single nucleotide polymorphisms (SNPs) of this gene and not specific to patients. The question of whether these missense mutations caused by SNPs alter the functional properties of M-CPTI remains unanswered. Thus, we examined whether these missense mutations are associated with any changes in the enzymatic properties of M-CPTI. None of these mutations was found to cause remarkable alteration of its enzymatic properties. Based on the comparison of amino acid sequences of M-CPTI among different animal species, the roles of these amino acids in the enzyme are discussed.
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Affiliation(s)
- Naoshi Yamazaki
- Faculty of Pharmaceutical Sciences, University of Tokushima, Shomachi-1, Tokushima, Japan.
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19
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Wolfgang MJ, Lane MD. Control of energy homeostasis: role of enzymes and intermediates of fatty acid metabolism in the central nervous system. Annu Rev Nutr 2006; 26:23-44. [PMID: 16704352 DOI: 10.1146/annurev.nutr.25.050304.092532] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The regulation of energy homeostasis is critical for normal physiology and survival. Energy flux must be rigorously monitored and adjusted to ensure that fuel intake and expenditure remain within acceptable limits. The central nervous system (CNS) is, in large part, responsible for conducting this energy-monitoring function and for integrating the numerous inputs. It has become evident that neurons of the CNS monitor and respond to levels of metabolic intermediates that reflect peripheral energy status. Intermediates in the fatty acid biosynthetic pathway have been implicated as hypothalamic signaling mediators that sense and respond to changes in circulating fuels. Genetic and pharmacologic manipulation of the enzymes of fatty acid metabolism have led to the hypothesis that neuronal metabolic intermediates affect neural outputs that modify both feeding behavior and energy expenditure. This review focuses on the regulatory roles of these enzymes and intermediates in the regulation of food intake and energy balance.
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Affiliation(s)
- Michael J Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
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20
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Eddy SF, Morin P, Storey KB. Differential expression of selected mitochondrial genes in hibernating little brown bats,Myotis lucifugus. ACTA ACUST UNITED AC 2006; 305:620-30. [PMID: 16721807 DOI: 10.1002/jez.a.294] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
High rates of non-shivering thermogenesis by brown adipose tissue accompanied by additional shivering thermogenesis in skeletal muscle provide the powerful reheating of body organs that allows hibernating mammals to return from their state of cold torpor back to euthermic function. Previous studies have suggested that changes to brown adipose mitochondria occur during hibernation and are partially responsible for its capacity for non-shivering thermogenesis. The current study shows that selected mitochondrial enzyme activities are elevated and selected genes and proteins are induced during torpor in brown adipose tissue of the little brown bat, Myotis lucifugus. Cytochrome oxidase activity in brown adipose tissue was more than 3-fold higher during torpor than in euthermic animals. Transcript levels of mitochondria-encoded genes, coxII and nad4, were also 3-4-fold higher during torpor, as evidenced by northern blotting. By contrast, transcripts of these genes were unchanged in skeletal muscle during torpor. Protein levels of carnitine palmitoyl transferase-1beta, an enzyme embedded in the outer membrane of the mitochondria that is the rate-limiting step enzyme in beta-oxidation, were also elevated by 2-fold during torpor in brown adipose but were unchanged in skeletal muscle. Cloning and sequencing of a 624 bp segment of cpt-1beta revealed a number of amino acid substitutions in the bat protein as compared to CPT-1beta from other mammals; these may be beneficial for enzyme function at low body temperatures during torpor. This study provides further evidence for a key role of mitochondria in hibernation.
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Affiliation(s)
- Sean F Eddy
- Institute of Biochemistry and Department of Chemistry Carleton University, Ottawa, Ont., Canada K1S 5B6.
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21
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Cheng Y, Dharancy S, Malapel M, Desreumaux P. Hepatitis C virus infection down-regulates the expression of peroxisome proliferator-activated receptor alpha and carnitine palmitoyl acyl-CoA transferase 1A. World J Gastroenterol 2006; 11:7591-6. [PMID: 16437683 PMCID: PMC4727219 DOI: 10.3748/wjg.v11.i48.7591] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To elucidate the role of the peroxisome proliferator-activated receptor alpha (PPARalpha) and its target gene carnitine palmitoyl acyl-CoA transferase 1A (CPT1A) in the pathogenesis of hepatitis C virus (HCV) infection. METHODS Liver samples were collected from the patients with chronic HCV infection and controls. HepG2 cells were transfected with vector pEF352neo carrying. Two independent clones (clone N3 and N4) stably expressing HCV core protein were analyzed. Total RNA was extracted from cells and liver tissues. PPARalpha and CPT1A mRNAs were quantified by real-time polymerase chain reaction (PCR) using SYBR Green Master. Total extracted proteins were separated by polyacrylamide gel electrophoresis, and electroblotted. Membranes were incubated with the anti-PPARalpha antibody, then with a swine anti-rabbit IgG conjugated to horseradish peroxidase for PPARalpha. Protein bands were revealed by an enhanced chemiluminescence reaction for PPARalpha. For immunohistochemical staining of PPARalpha, sections were incubated with the primary goat polyclonal antibody directed against PPARalpha at room temperature. RESULTS Real-time PCR indicated that the PPARalpha level and expression level of CPT1A gene in hepatitis C patients lowered significantly as compared with the controls (1.8+/-2.8 vs 13+/-3.4, P = 0.0002; 1.1+/-1.5 vs 7.4+/-1, P = 0.004). Western blot results showed that the level of PPARalpha protein in the livers of hepatitis C patients was lower than that in controls (2.3+/-0.3 vs 3.6+/-0.2, P = 0.009). The immunohistochemical staining results in chronic hepatitis C patients indicated a decrease in PPARalpha staining in hepatocytes compared with those in the control livers. The in vitro studies found that in the N3 and N4 colon stably expressing HCV core protein, the PPARalpha mRNA levels were significantly lower than that in the controls. CONCLUSION The impaired intrahepatic PPARalpha expression is associated with the pathogenic mechanism in hepatic injury during chronic HCV infection. HCV infection reduced the expression of PPARalpha and CPT1A at the level of not only mRNAs but also proteins. PPARalpha plays an important role in the pathogenesis of chronic HCV infection, but the impaired function of this nuclear receptor in HCV infection needs further studies.
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Affiliation(s)
- Yang Cheng
- Institute of Liver Diseases, Shanghai University of TCM, Shanghai 201203, China.
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22
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Roepstorff C, Halberg N, Hillig T, Saha AK, Ruderman NB, Wojtaszewski JFP, Richter EA, Kiens B. Malonyl-CoA and carnitine in regulation of fat oxidation in human skeletal muscle during exercise. Am J Physiol Endocrinol Metab 2005; 288:E133-42. [PMID: 15383373 DOI: 10.1152/ajpendo.00379.2004] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Intracellular mechanisms regulating fat oxidation were investigated in human skeletal muscle during exercise. Eight young, healthy, moderately trained men performed bicycle exercise (60 min, 65% peak O2 consumption) on two occasions, where they ingested either 1) a high-carbohydrate diet (H-CHO) or 2) a low-carbohydrate diet (L-CHO) before exercise to alter muscle glycogen content as well as to induce, respectively, low and high rates of fat oxidation. Leg fat oxidation was 122% higher during exercise in L-CHO than in H-CHO (P < 0.001). In keeping with this, the activity of alpha2-AMP-activated protein kinase (alpha2-AMPK) was increased twice as much in L-CHO as in H-CHO (P < 0.01) at 60 min of exercise. However, acetyl-CoA carboxylase (ACC)beta Ser221 phosphorylation was increased to the same extent (6-fold) under the two conditions. The concentration of malonyl-CoA was reduced 13% by exercise in both conditions (P < 0.05). Pyruvate dehydrogenase activity was higher during exercise in H-CHO than in L-CHO (P < 0.01). In H-CHO only, the concentrations of acetyl-CoA and acetylcarnitine were increased (P < 0.001), and the concentration of free carnitine was decreased (P < 0.01), by exercise. The data suggest that a decrease in the concentration of malonyl-CoA, secondary to alpha2-AMPK activation and ACC inhibition (by phosphorylation), contributes to the increase in fat oxidation observed at the onset of exercise regardless of muscle glycogen levels. They also suggest that, with high muscle glycogen, the availability of free carnitine may limit fat oxidation during exercise, due to its increased use for acetylcarnitine formation.
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Affiliation(s)
- Carsten Roepstorff
- The Copenhagen Muscle Research Centre, Department of Human Physiology, Institute of Exercise and Sport Sciences, University of Copenhagen, Copenhagen, Denmark.
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23
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Relat J, Nicot C, Gacias M, Woldegiorgis G, Marrero PF, Haro D. Pig muscle carnitine palmitoyltransferase I (CPTI beta), with low Km for carnitine and low sensitivity to malonyl-CoA inhibition, has kinetic characteristics similar to those of the rat liver (CPTI alpha) enzyme. Biochemistry 2004; 43:12686-91. [PMID: 15449958 DOI: 10.1021/bi0488597] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The outer mitochondrial membrane enzyme carnitine palmitoyltransferase I (CPTI) catalyzes the initial and regulatory step in the beta-oxidation of long-chain fatty acids. There are two well-characterized isotypes of CPTI: CPTIalpha (also known as L-CPTI) and CPTIbeta (also known as M-CPTI) that in human and rat encode for enzymes with very different kinetic properties and sensitivity to malonyl-CoA inhibition. Kinetic hallmarks of the CPTIalpha are high affinity for carnitine and low sensitivity to malonyl-CoA inhibition, while the opposite characteristics, low affinity for carnitine and high sensitivity to malonyl-CoA, are intrinsic to the CPTIbeta isotype. We have isolated the pig CPTIbeta cDNA which encodes for a protein of 772 amino acids that shares extensive sequence identity with human (88%), rat (85%), and mouse (86%) CPTIbeta, while the degree of homology with the CPTIalpha from human (61%), rat (62%), and mouse (60%) is much lower. However, when expressed in the yeast Pichia pastoris, pig CPTIbeta shows kinetic characteristics similar to those of the CPTIalpha isotype. Thus, the pig CPTIbeta, unlike the corresponding human or rat enzyme, has a high affinity for carnitine (K(m) = 197 microM) and low sensitive to malonyl-CoA inhibition (IC(50) = 906 nM). Therefore, the recombinant pig CPTIbeta has unique kinetic characteristics, which makes it a useful model to study the structure-function relationship of the CPTI enzymes.
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Affiliation(s)
- Joana Relat
- Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, 08028 Barcelona, Spain
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Roepstorff C, Vistisen B, Roepstorff K, Kiens B. Regulation of plasma long-chain fatty acid oxidation in relation to uptake in human skeletal muscle during exercise. Am J Physiol Endocrinol Metab 2004; 287:E696-705. [PMID: 15186996 DOI: 10.1152/ajpendo.00001.2004] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the present study, we investigated possible sites of regulation of long-chain fatty acid (LCFA) oxidation in contracting human skeletal muscle. Leg plasma LCFA kinetics were determined in eight healthy men during bicycling (60 min, 65% peak oxygen uptake) with either high (H-FOX) or low (L-FOX) leg fat oxidation (H-FOX: 1,098 +/- 140; L-FOX: 494 +/- 84 micromol FA/min, P < 0.001), which was achieved by manipulating preexercise muscle glycogen (H-FOX: 197 +/- 21; L-FOX: 504 +/- 25 mmol/kg dry wt, P < 0.001). Several blood metabolites and hormones were kept nearly similar between trials by allocating a preexercise meal and infusing glucose intravenously during exercise. During exercise, leg plasma LCFA fractional extraction was identical between trials (H-FOX: 17.8 +/- 1.6; L-FOX: 18.2 +/- 1.8%, not significant), suggesting similar LCFA transport capacity in muscle. On the contrary, leg plasma LCFA oxidation was 99% higher in H-FOX than in L-FOX (421 +/- 47 vs. 212 +/- 37 micromol/min, P < 0.001). Probably due to the slightly higher (P < 0.01) plasma LCFA concentration in H-FOX than in L-FOX, leg plasma LCFA uptake was nonsignificantly (P = 0.17) higher (25%) in H-FOX than in L-FOX, yet the fraction of plasma LCFA uptake oxidized was 61% higher (P < 0.05) in H-FOX than in L-FOX. Accordingly, the muscle content of several lipid-binding proteins did not differ significantly between trials, although fatty acid translocase/CD36 and caveolin-1 were elevated (P < 0.05) by the high-intensity exercise and dietary manipulation allocated on the day before the experimental trial. The present data suggest that, in contracting human skeletal muscle with different fat oxidation rates achieved by manipulating preexercise glycogen content, transsarcolemmal transport is not limiting plasma LCFA oxidation. Rather, the latter seems to be limited by intracellular regulatory mechanisms.
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Affiliation(s)
- Carsten Roepstorff
- The Copenhagen Muscle Research Centre, Institute of Exercise and Sport Sciences, Department of Human Physiology, Universitetsparken 13, DK-2100 Ø, Denmark.
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Bartelds B, Takens J, Smid GB, Zammit VA, Prip-Buus C, Kuipers JRG, van der Leij FR. Myocardial carnitine palmitoyltransferase I expression and long-chain fatty acid oxidation in fetal and newborn lambs. Am J Physiol Heart Circ Physiol 2004; 286:H2243-8. [PMID: 14751860 DOI: 10.1152/ajpheart.00864.2003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Carnitine palmitoyltransferase I (CPT I) catalyzes the conversion of acyl-CoA to acylcarnitine at the outer mitochondrial membrane and is a key enzyme in the control of long-chain fatty acid (LC-FA) oxidation. Because myocardial LC-FA oxidation increases dramatically after birth, we determined the extent to which CPT I expression contributes to these changes in the perinatal lamb. We measured the steady-state level of transcripts of the CPT1A and CPT1B genes, which encode the liver (L-CPT I) and muscle CPT I (M-CPT I) isoforms, respectively, as well as the amount of these proteins, their total activity, and the amount of carnitine in left ventricular tissue from fetal and newborn lambs. We compared these data with previously obtained myocardial FA oxidation rates in vivo in the same model. The results showed that CPT1B was already expressed before birth and that total CPT I expression transiently increased after birth. The protein level of M-CPT I was high throughout development, whereas that of L-CPT I was only transiently upregulated in the first week after birth. The total CPT I activity in vitro also increased after birth. However, the increase in myocardial FA oxidation measured in vivo (112-fold) by far exceeded the increase in gene expression (2.2-fold), protein amount (1.1-fold), and enzyme activity (1.2-fold) in vitro. In conclusion, these results stress the importance of substrate supply per se in the postnatal increase in myocardial FA oxidation. M-CPT I is expressed throughout perinatal development, making it a primary target for metabolic modulation of myocardial FA oxidation.
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Affiliation(s)
- Beatrijs Bartelds
- Dept. of Pediatrics, University of Groningen, Research Lab CMCV-2, Hanzeplein 1, NL-9713 GZ Groningen, The Netherlands
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