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Sarri L, Balcells J, Seradj AR, de la Fuente G. Protein turnover in pigs: A review of interacting factors. J Anim Physiol Anim Nutr (Berl) 2024; 108:451-469. [PMID: 37975299 DOI: 10.1111/jpn.13906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 08/24/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
Protein turnover defines the balance between two continuous and complex processes of protein metabolism, synthesis and degradation, which determine their deposition in tissues. Although the liver and intestine have been studied extensively for their important roles in protein digestion, absorption and metabolism, the study of protein metabolism has focused mainly on skeletal muscle tissue to understand the basis for its growth. Due to the high adaptability of skeletal muscle, its protein turnover is greatly affected by different internal and external factors, contributing to carcass lean-yield and animal growth. Amino acid (AA) labelling and tracking using isotope tracer methodology, together with the study of myofiber type profiling, signal transduction pathways and gene expression, has allowed the analysis of these mechanisms from different perspectives. Positive stimuli such as increased nutrient availability in the diet (e.g., AA), physical activity, the presence of certain hormones (e.g., testosterone) or a more oxidative myofiber profile in certain muscles or pig genotypes promote increased upregulation of translation and transcription-related genes, activation of mTORC1 signalling mechanisms and increased abundance of satellite cells, allowing for more efficient protein synthesis. However, fasting, animal aging, inactivity and stress, inflammation or sepsis produce the opposite effect. Deepening the understanding of modifying factors and their possible interaction may contribute to the design of optimal strategies to better control tissue growth and nutrient use (i.e., protein and AA), and thus advance the precision feeding strategy.
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Affiliation(s)
- Laura Sarri
- Departament de Ciència Animal, Universitat de Lleida- Agrotecnio-CERCA Center, Lleida, Spain
| | - Joaquim Balcells
- Departament de Ciència Animal, Universitat de Lleida- Agrotecnio-CERCA Center, Lleida, Spain
| | - Ahmad Reza Seradj
- Departament de Ciència Animal, Universitat de Lleida- Agrotecnio-CERCA Center, Lleida, Spain
| | - Gabriel de la Fuente
- Departament de Ciència Animal, Universitat de Lleida- Agrotecnio-CERCA Center, Lleida, Spain
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Mahalingam S, McClelland GB, Scott GR. Evolved changes in the intracellular distribution and physiology of muscle mitochondria in high-altitude native deer mice. J Physiol 2017; 595:4785-4801. [PMID: 28418073 DOI: 10.1113/jp274130] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/12/2017] [Indexed: 12/11/2022] Open
Abstract
KEY POINTS Mitochondrial function changes over time at high altitudes, but the potential benefits of these changes for hypoxia resistance remains unclear. We used high-altitude-adapted populations of deer mice, which exhibit enhanced aerobic performance in hypoxia, to examine whether changes in mitochondrial physiology or intracellular distribution in the muscle contribute to hypoxia resistance. Permeabilized muscle fibres from the gastrocnemius muscle had higher respiratory capacities in high-altitude mice than in low-altitude mice. Highlanders also had higher mitochondrial volume densities, due entirely to an enriched abundance of subsarcolemmal mitochondria, such that more mitochondria were situated near the cell membrane and adjacent to capillaries. There were several effects of hypoxia acclimation on mitochondrial function, some of which were population specific, but they differed from the evolved changes in high-altitude natives, which probably provide a better indication of adaptive traits that improve performance and hypoxia resistance at high altitudes. ABSTRACT High-altitude natives that have evolved to live in hypoxic environments provide a compelling system to understand how animals can overcome impairments in oxygen availability. We examined whether these include changes in mitochondrial physiology or intracellular distribution that contribute to hypoxia resistance in high-altitude deer mice (Peromyscus maniculatus). Mice from populations native to high and low altitudes were born and raised in captivity, and as adults were acclimated to normoxia or hypobaric hypoxia (equivalent to 4300 m elevation). We found that highlanders had higher respiratory capacities in the gastrocnemius (but not soleus) muscle than lowlanders (assessed using permeabilized fibres with single or multiple inputs to the electron transport system), due in large part to higher mitochondrial volume densities in the gastrocnemius. The latter was attributed to an increased abundance of subsarcolemmal (but not intermyofibrillar) mitochondria, such that more mitochondria were situated near the cell membrane and adjacent to capillaries. Hypoxia acclimation had no significant effect on these population differences, but it did increase mitochondrial cristae surface densities of mitochondria in both populations. Hypoxia acclimation also altered the physiology of isolated mitochondria by affecting respiratory capacities and cytochrome c oxidase activities in population-specific manners. Chronic hypoxia decreased the release of reactive oxygen species by isolated mitochondria in both populations. There were subtle differences in O2 kinetics between populations, with highlanders exhibiting increased mitochondrial O2 affinity or catalytic efficiency in some conditions. Our results suggest that evolved changes in mitochondrial physiology in high-altitude natives are distinct from the effects of hypoxia acclimation, and probably provide a better indication of adaptive traits that improve performance and hypoxia resistance at high altitudes.
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Affiliation(s)
- Sajeni Mahalingam
- Department of Biology, McMaster University, Hamilton, Ontario, Canada, L8S 4K1
| | - Grant B McClelland
- Department of Biology, McMaster University, Hamilton, Ontario, Canada, L8S 4K1
| | - Graham R Scott
- Department of Biology, McMaster University, Hamilton, Ontario, Canada, L8S 4K1
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Kim GD, Yang HS, Jeong JY. Comparison of Characteristics of Myosin Heavy Chain-based Fiber and Meat Quality among Four Bovine Skeletal Muscles. Korean J Food Sci Anim Resour 2016; 36:819-828. [PMID: 28115894 PMCID: PMC5243967 DOI: 10.5851/kosfa.2016.36.6.819] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 12/03/2016] [Accepted: 12/05/2016] [Indexed: 11/06/2022] Open
Abstract
Muscle fiber characteristics account for meat quality and muscle fibers are mainly classified into three or more types according to their contractile and metabolic properties. However, the majority of previous studies on bovine skeletal muscle are based on myosin ATPase activity. In the present study, the differences in the characteristics of muscle fibers classified by the expression of myosin heavy chain (MHC) among four bovine skeletal muscles such as longissimus thoracis (LT), psoas major (PM), semimembranosus (SM) and semitendinosus (ST) and their relationships to beef quality were investigated. MHCs 2x, 2a and slow were identified by LC-MS/MS and IIX, IIA and I fiber types were classified. PM, which had the smallest size and highest density of fibers regardless of type, showed the highest myoglobin content, CIE L*, a*, b* and sarcomere length (p<0.05), whereas ST with the highest composition of IIX, showed high shear force and low sarcomere length (p<0.05). The correlation coefficients between muscle fiber characteristics and meat quality showed that type IIX is closely related to poor beef quality and that a high density of small-sized fibers is related to redness and tenderness. Therefore, the differences in meat quality between muscles can be explained by the differences in muscle fiber characteristics, and especially, the muscles with good quality are composed of more small-sized fibers regardless of fiber type.
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Affiliation(s)
- Gap-Don Kim
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea; Department of Animal Sciences, University of Illinois, Urbana-Champaign, IL 61801, USA
| | - Han-Sul Yang
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea; Division of Applied Life Science (BK21 plus), Gyeongsang National University, Jinju 52828, Korea
| | - Jin-Yeon Jeong
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea; Division of Applied Life Science (BK21 plus), Gyeongsang National University, Jinju 52828, Korea
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Skeletal muscles respond differently when piglets are offered a diet 30 % deficient in total sulfur amino acid for 10 days. Eur J Nutr 2015; 55:117-26. [DOI: 10.1007/s00394-014-0830-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 12/30/2014] [Indexed: 11/30/2022]
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Joo S, Kim G, Hwang Y, Ryu Y. Control of fresh meat quality through manipulation of muscle fiber characteristics. Meat Sci 2013; 95:828-36. [DOI: 10.1016/j.meatsci.2013.04.044] [Citation(s) in RCA: 241] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/14/2013] [Accepted: 04/15/2013] [Indexed: 10/26/2022]
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Faure J, Lebret B, Bonhomme N, Ecolan P, Kouba M, Lefaucheur L. Metabolic adaptation of two pig muscles to cold rearing conditions1. J Anim Sci 2013; 91:1893-906. [DOI: 10.2527/jas.2012-5828] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- J. Faure
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
| | - B. Lebret
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
| | - N. Bonhomme
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
| | - P. Ecolan
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
| | - M. Kouba
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
| | - L. Lefaucheur
- INRA, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35590 Saint-Gilles, France
- Agrocampus Ouest, UMR1348 Physiologie, Environnement et Génétique pour l'Animal et les Systèmes d'Elevage, F-35000 Rennes, France
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Perruchot MH, Ecolan P, Sorensen IL, Oksbjerg N, Lefaucheur L. In vitro characterization of proliferation and differentiation of pig satellite cells. Differentiation 2012; 84:322-9. [PMID: 23023068 DOI: 10.1016/j.diff.2012.08.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/31/2012] [Accepted: 08/09/2012] [Indexed: 01/21/2023]
Abstract
Skeletal muscle contains various muscle fiber types exhibiting different contractile properties based on the myosin heavy chain (MyHC) isoform profile. Muscle fiber type composition is highly variable and influences growth performance and meat quality, but underlying mechanisms regulating fiber type composition remain poorly understood. The aim of the present work was to develop a model based on muscle satellite cell culture to further investigate the regulation of adult MyHC isoforms expression in pig skeletal muscle. Satellite cells were harvested from the mostly fast-twitch glycolytic longissimus (LM) and predominantly slow-twitch oxidative rhomboideus (RM) muscles of 6-week-old piglets. Satellite cells were allowed to proliferate up to 80% confluence, reached after 7 day of proliferation (D7), and then induced to differentiate. Kinetics of proliferation and differentiation were similar between muscles and more than 95% of the cells were myogenic (desmin positive) at D7 with a fusion index reaching 65 ± 9% after 4 day of differentiation. One-dimensional SDS polyacrylamide gel electrophoresis revealed that satellite cells from both muscles only expressed the embryonic and fetal MyHC isoforms in culture, without any of the adult MyHC isoforms that were expressed in vivo. Interestingly, triiodothyronine (T3) induced de novo expression of adult fast and α-cardiac MyHC in vitro making our culture system a valuable tool to study de novo expression of adult MyHC isoforms and its regulation by intrinsic and/or extrinsic factors.
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Affiliation(s)
- Marie-Hélène Perruchot
- INRA, UMR Physiology, Environnement and Genetics for the Animal and Livestock Systems, Saint-Gilles, France.
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Lefaucheur L. A second look into fibre typing – Relation to meat quality. Meat Sci 2010; 84:257-70. [DOI: 10.1016/j.meatsci.2009.05.004] [Citation(s) in RCA: 206] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 04/16/2009] [Accepted: 05/03/2009] [Indexed: 12/25/2022]
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Postnatal regulation of myosin heavy chain isoform expression and metabolic enzyme activity by nutrition. Br J Nutr 2007. [DOI: 10.1017/s0007114500001410] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Development of muscle is critically dependent on several hormones which in turn are regulated by nutritional status. We therefore determined the impact of mild postnatal undernutrition on key markers of myofibre function: type I slow myosin heavy chain (MyHC) isoform, myosin ATPase, succinate dehydrogenase and α-glycerophosphate dehydrogenase. In situ hybridization, immunocytochemistry and enzyme histochemistry were used to assess functionally distinct muscles from 6-week-old pigs which had been fed an optimal (6 % (60 g food/kg body weight per d)) or low (2 % (20 g food/kg per d)) intake for 3 weeks, and kept at 26°C. Nutritional status had striking muscle-specific influences on contractile and metabolic properties of myofibres, and especially on myosin isoform expression. A low food intake upregulated slow MyHC mRNA and protein levels in rhomboideus by 53 % (P < 0·01) and 18 % (P < 0·05) respectively; effects in longissimus dorsi, soleus and diaphragm were not significant. The oxidative capacity of all muscles increased on the low intake, albeit to varying extents: longissimus dorsi (55 %), rhomboideus (30 %), soleus (21 %), diaphragm (7 %). Proportions of slow oxidative fibres increased at the expense of fast glycolytic fibres. These novel findings suggest a critical role for postnatal nutrition in regulating myosin gene expression and muscle phenotype. They have important implications for optimal development of human infants: on a low intake, energetic efficiency will increase and the integrated response to many metabolic and growth hormones will alter, since both are dependent on myofibre type. Mechanisms underlying these changes probably involve complex interactions between hormones acting as nutritional signals and differential effects on their cell membrane receptors or nuclear receptors.
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Lombardi A, Damon M, Vincent A, Goglia F, Herpin P. Characterisation of oxidative phosphorylation in skeletal muscle mitochondria subpopulations in pig: a study using top-down elasticity analysis. FEBS Lett 2000; 475:84-8. [PMID: 10858493 DOI: 10.1016/s0014-5793(00)01633-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In skeletal muscle, two mitochondrial populations are present which, on the basis of their localisation, are termed intermyofibrillar and subsarcolemmal mitochondria (IMF and SS, respectively). These two populations have different biochemical characteristics and show different responses to physiological stimuli. In this paper, we characterise the oxidative phosphorylation of SS and IMF using 'top-down' elasticity analysis. We excluded the possibility that their different characteristics can be attributed to a different degree of breakage of the two types of mitochondria due to the different isolation procedures used in their preparation. The higher respiration rate and higher respiratory control ratio shown by IMF compared with those shown by SS are principally due to the higher activities of the reactions involved in substrate oxidation as confirmed by the measurement of cytochrome oxidase activity. There is no difference in the leak of protons across the inner mitochondrial membrane between IMF and SS; a faster rate of ATP synthesis and turnover is driven by the lower membrane potential in SS compared with in IMF.
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Affiliation(s)
- A Lombardi
- Dipartimento di Fisiologia Generale ed Ambientale, Università degli Studi di Napoli Federico II, Naples, Italy
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Hocquette J, Ortigues-Marty I, Pethick D, Herpin P, Fernandez X. Nutritional and hormonal regulation of energy metabolism in skeletal muscles of meat-producing animals. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0301-6226(98)00187-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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13
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Bénistant C, Duchamp C, Cohen-Adad F, Rouanet JL, Barré H. Increased in vitro fatty acid supply and cellular transport capacities in cold-acclimated ducklings (Cairina moschata). THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:R683-90. [PMID: 9728063 DOI: 10.1152/ajpregu.1998.275.3.r683] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In cold-acclimated (CA) birds, lipids play a crucial role in regulatory thermogenesis by acting both as substrates for and activators of thermogenic processes. The capacity to supply lipids to thermogenic tissues, which could limit cold thermogenesis, was assessed in CA ducklings (5 wk old, 4 degrees C) and compared with thermoneutral controls (TN, 25 degrees C). In CA ducklings, basal lipolytic activity of adipose tissue fragments was higher (202 +/- 9 vs. 130 +/- 14 nmol glycerol released . 100 mg tissue-1 . h-1, +55%) than in TN controls, while glucagon had a much higher stimulatory effect (+140 to +500% depending on dose). This was consistent with increased plasma levels of nonesterified fatty acids (FA, +57%) and glycerol (+31%) in vivo. In vitro endothelial lipase activity per organ was higher in CA than in TN ducklings in red gastrocnemius muscle (6.3 +/- 0.6 vs. 3.5 +/- 0.3 microeq nonesterified FA released per hour, +80%) and liver (+55%). The intracellular FA-binding capacity of (12-18 kDa) proteins was higher in gastrocnemius muscle (+43%) and liver (+74%) from CA ducklings. In gastrocnemius, it was linked to a higher content (21 +/- 2 vs. 15 +/- 2 microg/mg protein, +37%) of an intracellular 15.4-kDa FA-binding protein. These in vitro results indicate that coordinated increases in FA supply from adipose tissue, cellular uptake of lipoprotein-derived FA, and intracellular FA transport capacity occur in CA ducklings endowed with higher thermogenic capacity and cold endurance.
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Affiliation(s)
- C Bénistant
- Unité Mixte de Recherches 5578 Centre National de la Recherche Scientifique-Université Claude Bernard Lyon I, Laboratoire Associé Institut National de la Recherche Agronomique, Villeurbanne, France
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Schmidt I, Herpin P. Postnatal changes in mitochondrial protein mass and respiration in skeletal muscle from the newborn pig. Comp Biochem Physiol B Biochem Mol Biol 1997; 118:639-47. [PMID: 9467875 DOI: 10.1016/s0305-0491(97)00268-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Quantitative and functional changes occurring in mitochondria were studied in pig skeletal muscle between birth and 5 days of life. Postnatal changes were followed separately on intermyofibrillar and subsarcolemmal mitochondria isolated from rhomboïdeus (RH) and longissimus dorsi (LD) muscles. The integrity and purity of the isolated mitochondria was checked by electron microscopic observations. The mass of mitochondrial protein was not different between muscles at birth. It increased tremendously during the first 5 days of life, by 49% in LD (P < 0.001) and 93% in RH (P < 0.001) muscle and was 30% higher in RH than in LD muscle at 5 days of life (P < 0.05). Mitochondria isolated from RH muscle exhibited 30% higher oxidative and phosphorylative capacities than those from LD muscle at 5 days of life (P < 0.05). Intermyofibrillar (IM) mitochondria had high respiration rate, enzyme activities and coupling parameters (respiratory control ratio, phosphorus-oxygen ratio) from birth. Subsarcolemmal (SS) mitochondria were less active than IM mitochondria; their respiration rate and enzyme activities were 60% lower (P < 0.01) and increased with age, particularly in LD muscle (P < 0.05). Short-term cold exposure had no effect on mitochondrial mass and activity. These results suggest that muscle mitochondria are functional from birth and are changing primarily quantitatively. SS and IM mitochondria exhibit specific changes that are probably involved in the postnatal acquisition of skeletal muscle oxidative metabolism.
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Affiliation(s)
- I Schmidt
- INRA, Station de Recherches Porcines, Saint Gilles, France
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Berthon D, Herpin P, Bertin R, De Marco F, le Dividich J. Metabolic changes associated with sustained 48-hr shivering thermogenesis in the newborn pig. Comp Biochem Physiol B Biochem Mol Biol 1996; 114:327-35. [PMID: 8840509 DOI: 10.1016/0305-0491(96)00044-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Metabolic changes associated with sustained 48-hr shivering thermogenesis were studied in piglets maintained at 34 (thermoneutrality) or 25 degrees C (cold) between 6 and 54 hr of life. Despite their high shivering activity and elevated heat production, cold-exposed piglets exhibited a slightly lower rectal temperature than thermoneutral animals (-1.1 degrees C; P < 0.01) at the end of the treatment. The enhancement of heat production and shivering activity were associated with a decrease in muscle glycogen (-47%; P < 0.05) and total lipid content (-23%; P < 0.05), a reduction of blood lactate levels (P < 0.05) and an enhancement of muscle cytochrome oxidase activity (+20%; P < 0.05) which suggests that muscle oxidative potential was increased by cold exposure. Potential for capturing lipids (lipoprotein lipase activity) was also higher in the red rhomboideus muscle (+71%; P < 0.01) and lower in adipose tissue (-58%; P < 0.01) of the cold-exposed piglets. Measurements performed at the mitochondrial level show no changes in rhomboideus muscle, but respiratory capacities (state IV and FCCP-stimulated respiration) and intermyofibrillar mitochondria oxidative and phosphorylative (creatine kinase activity) capacities were enhanced in longissimus dorsi muscle (P < 0.05). These changes may contribute to provide muscles with nonlimiting amount of readily oxidable substrates and ATP necessary for shivering thermogenesis. A rise in plasma norepinephrine levels was also observed during the second day of cold exposure (P < 0.05).
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Affiliation(s)
- D Berthon
- INRA, Station de Recherches Porcines, St Gilles, France
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Effects of climatic conditions on the performance, metabolism and health status of weaned piglets: a review. ACTA ACUST UNITED AC 1994. [DOI: 10.1016/0301-6226(94)90052-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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