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Reed CH, Tystahl AC, Eo H, Buhr TJ, Bauer EE, Lee JH, Clark PJ, Valentine RJ. The Influence of Stress and Binge-Patterned Alcohol Drinking on Mouse Skeletal Muscle Protein Synthesis and Degradation Pathways. Biomolecules 2024; 14:527. [PMID: 38785934 PMCID: PMC11118922 DOI: 10.3390/biom14050527] [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] [Received: 02/12/2024] [Revised: 03/30/2024] [Accepted: 04/09/2024] [Indexed: 05/25/2024] Open
Abstract
Adverse experiences (e.g., acute stress) and alcohol misuse can both impair skeletal muscle homeostasis, resulting in reduced protein synthesis and greater protein breakdown. Exposure to acute stress is a significant risk factor for engaging in alcohol misuse. However, little is known about how these factors together might further affect skeletal muscle health. To that end, this study investigated the effects of acute stress exposure followed by a period of binge-patterned alcohol drinking on signaling factors along mouse skeletal muscle protein synthesis (MPS) and degradation (MPD) pathways. Young adult male C57BL/6J mice participated in the Drinking in the Dark paradigm, where they received 2-4 h of access to 20% ethanol (alcohol group) or water (control group) for four days to establish baseline drinking levels. Three days later, half of the mice in each group were either exposed to a single episode of uncontrollable tail shocks (acute stress) or remained undisturbed in their home cages (no stress). Three days after stress exposure, mice received 4 h of access to 20% ethanol (alcohol) to model binge-patterned alcohol drinking or water for ten consecutive days. Immediately following the final episode of alcohol access, mouse gastrocnemius muscle was extracted to measure changes in relative protein levels along the Akt-mTOR MPS, as well as the ubiquitin-proteasome pathway (UPP) and autophagy MPD pathways via Western blotting. A single exposure to acute stress impaired Akt singling and reduced rates of MPS, independent of alcohol access. This observation was concurrent with a potent increase in heat shock protein seventy expression in the muscle of stressed mice. Alcohol drinking did not exacerbate stress-induced alterations in the MPS and MPD signaling pathways. Instead, changes in the MPS and MPD signaling factors due to alcohol access were primarily observed in non-stressed mice. Taken together, these data suggest that exposure to a stressor of sufficient intensity may cause prolonged disruptions to signaling factors that impact skeletal muscle health and function beyond what could be further induced by periods of alcohol misuse.
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Affiliation(s)
- Carter H Reed
- Department of Biology, Grand View University, Des Moines, IA 50316, USA;
| | - Anna C. Tystahl
- Department of Kinesiology, Iowa State University, Ames, IA 50011, USA; (A.C.T.)
| | - Hyeyoon Eo
- Department of Kinesiology, Iowa State University, Ames, IA 50011, USA; (A.C.T.)
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Trevor J. Buhr
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Ella E. Bauer
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Ji Heun Lee
- Department of Kinesiology, Iowa State University, Ames, IA 50011, USA; (A.C.T.)
| | - Peter J. Clark
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA
| | - Rudy J. Valentine
- Department of Physical Therapy and Kinesiology, University of Massachusetts Lowell, Lowell, MA 01854, USA
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Carabulea AL, Janeski JD, Naik VD, Chen K, Mor G, Ramadoss J. A multi-organ analysis of the role of mTOR in fetal alcohol spectrum disorders. FASEB J 2023; 37:e22897. [PMID: 37000494 PMCID: PMC10841000 DOI: 10.1096/fj.202201865r] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 02/21/2023] [Accepted: 03/16/2023] [Indexed: 04/01/2023]
Abstract
Alcohol exposure during gestation can lead to fetal alcohol spectrum disorders (FASD), an array of cognitive and physical developmental impairments. Over the past two and a half decades, Mammalian Target of Rapamycin (mTOR) has emerged at the nexus of many fields of study, and has recently been implicated in FASD etiology. mTOR plays an integral role in modulating anabolic and catabolic activities, including protein synthesis and autophagy. These processes are vital for proper development and can have long lasting effects following alcohol exposure, such as impaired hippocampal and synapse formation, reduced brain size, as well as cognitive, behavioral, and memory impairments. We highlight recent advances in the field of FASD, primarily with regard to animal model discoveries and discuss the interaction between alcohol and mTOR in the context of various tissues, including brain, placenta, bone, and muscle, with respect to developmental alcohol exposure paradigms. The current review focuses on novel FASD research within the context of the mTOR signaling and sheds light on mechanistic etiologies at various biological levels including molecular, cellular, and functional, across multiple stages of development and illuminates the dichotomy between the different mTOR complexes and their unique signaling roles.
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Affiliation(s)
- Alexander L. Carabulea
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
| | - Joseph D. Janeski
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
| | - Vishal D. Naik
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
| | - Kang Chen
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
- Barbara Ann Karmanos Cancer InstituteWayne State UniversityDetroitMichiganUSA
| | - Gil Mor
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
- Department of Physiology, School of MedicineWayne State UniversityDetroitMichiganUSA
| | - Jayanth Ramadoss
- Department of Obstetrics & Gynecology, C.S. Mott Center for Human growth and Development, School of MedicineWayne State UniversityDetroitMichiganUSA
- Department of Physiology, School of MedicineWayne State UniversityDetroitMichiganUSA
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Willemse L, Terburgh K, Louw R. A ketogenic diet alters mTOR activity, systemic metabolism and potentially prevents collagen degradation associated with chronic alcohol consumption in mice. Metabolomics 2023; 19:43. [PMID: 37076659 PMCID: PMC10115735 DOI: 10.1007/s11306-023-02006-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 03/31/2023] [Indexed: 04/21/2023]
Abstract
INTRODUCTION A ketogenic diet (KD), which is a high fat, low carbohydrate diet has been shown to inhibit the mammalian target of rapamycin (mTOR) pathway and alter the redox state. Inhibition of the mTOR complex has been associated with the attenuation and alleviation of various metabolic and- inflammatory diseases such as neurodegeneration, diabetes, and metabolic syndrome. Various metabolic pathways and signalling mechanisms have been explored to assess the therapeutic potential of mTOR inhibition. However, chronic alcohol consumption has also been reported to alter mTOR activity, the cellular redox- and inflammatory state. Thus, a relevant question that remains is what effect chronic alcohol consumption would have on mTOR activity and overall metabolism during a KD-based intervention. OBJECTIVES The aim of this study was to evaluate the effect of alcohol and a KD on the phosphorylation of the mTORC1 target p70S6K, systemic metabolism as well as the redox- and inflammatory state in a mouse model. METHODS Mice were fed either a control diet with/without alcohol or a KD with/without alcohol for three weeks. After the dietary intervention, samples were collected and subjected towards western blot analysis, multi-platform metabolomics analysis and flow cytometry. RESULTS Mice fed a KD exhibited significant mTOR inhibition and reduction in growth rate. Alcohol consumption alone did not markedly alter mTOR activity or growth rate but moderately increased mTOR inhibition in mice fed a KD. In addition, metabolic profiling showed alteration of several metabolic pathways as well as the redox state following consumption of a KD and alcohol. A KD was also observed to potentially prevent bone loss and collagen degradation associated with chronic alcohol consumption, as indicated by hydroxyproline metabolism. CONCLUSION This study sheds light on the influence that a KD alongside alcohol intake can exert on not just mTOR, but also their effect on metabolic reprogramming and the redox state.
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Affiliation(s)
- Luciano Willemse
- Human Metabolomics, Faculty of Natural and Agricultural Sciences, North-West University (Potchefstroom Campus), Private Bag X6001, Potchefstroom, South Africa
| | - Karin Terburgh
- Human Metabolomics, Faculty of Natural and Agricultural Sciences, North-West University (Potchefstroom Campus), Private Bag X6001, Potchefstroom, South Africa
| | - Roan Louw
- Human Metabolomics, Faculty of Natural and Agricultural Sciences, North-West University (Potchefstroom Campus), Private Bag X6001, Potchefstroom, South Africa.
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Prokopidis K, Witard OC. Understanding the role of smoking and chronic excess alcohol consumption on reduced caloric intake and the development of sarcopenia. Nutr Res Rev 2022; 35:197-206. [PMID: 34027849 DOI: 10.1017/s0954422421000135] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This narrative review provides mechanistic insight into the biological link between smoking and/or chronic excess alcohol consumption, and increased risk of developing sarcopenia. Although the combination of excessive alcohol consumption and smoking is often associated with ectopic adipose deposition, this review is focused on the context of a reduced caloric intake (leading to energy deficit) that also may ensue due to either lifestyle habit. Smoking is a primary cause of periodontitis and chronic obstructive pulmonary disease that both induce swallowing difficulties, inhibit taste and mastication, and are associated with increased risk of muscle atrophy and mitochondrial dysfunction. Smoking may contribute to physical inactivity, energy deficit via reduced caloric intake, and increased systemic inflammation, all of which are factors known to suppress muscle protein synthesis rates. Moreover, chronic excess alcohol consumption may result in gut microbiota dysbiosis and autophagy-induced hyperammonemia, initiating the up-regulation of muscle protein breakdown and down-regulation of muscle protein synthesis via activation of myostatin, AMPK and REDD1, and deactivation of IGF-1. Future research is warranted to explore the link between oral healthcare management and personalised nutrition counselling in light of potential detrimental consequences of chronic smoking on musculoskeletal health outcomes in older adults. Experimental studies should investigate the impact of smoking and chronic excess alcohol consumption on the gut-brain axis, and explore biomarkers of smoking-induced oral disease progression. The implementation of behavioural change interventions and health policies regarding smoking and alcohol intake habits may mitigate the clinical and financial burden of sarcopenia on the healthcare system.
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Affiliation(s)
- Konstantinos Prokopidis
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, White City, London, UK
| | - Oliver C Witard
- Centre for Human and Applied Physiological Sciences, School of Basic and Medical Biosciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
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Reed CH, Buhr TJ, Tystahl AC, Bauer EE, Clark PJ, Valentine RJ. The effects of voluntary binge-patterned ethanol ingestion and daily wheel running on signaling of muscle protein synthesis and degradation in female mice. Alcohol 2022; 104:45-52. [PMID: 35926812 DOI: 10.1016/j.alcohol.2022.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/17/2022] [Accepted: 06/22/2022] [Indexed: 01/26/2023]
Abstract
Excessive ethanol ingestion can reduce skeletal muscle protein synthesis (MPS) through the disruption of signaling along the Akt-mTOR pathway and increase muscle protein degradation (MPD) through the Ubiquitin Proteasome Pathway (UPP) and autophagy. Identification of interventions that curb the disrupting effects of alcohol misuse on MPS and MPD are of central importance for the prevention of chronic health complications that arise from muscle loss. Physical activity is one potential strategy to combat the deleterious effects of alcohol on skeletal muscle. Therefore, the purpose of this study was to investigate the interaction between daily wheel running and binge-patterned ethanol consumption, through episodes of voluntary binge-patterned ethanol drinking, on signaling factors along the Akt-mTOR, Ubiquitin-Proteasome, and autophagy pathways. Adult female C57BL/6J mice received daily access to cages with or without running wheels for 2.5 h/day for five weeks. During the final five days of the study, mice received 2-4 h of daily access to sipper tubes containing water (n = 14 sedentary; n = 15 running) or 20% ethanol (n = 14 sedentary; n = 16 running) 30 min after running wheel access, using the "Drinking in the Dark" (DID) model of binge-patterned ethanol consumption. Immediately after the final episode of DID, gastrocnemius muscle was extracted. Western blotting was performed to measure proteins along Akt-mTOR, Ubiquitin-Proteasome, and autophagy pathways, and PCR was used to assess mRNA expression of atrogenes. Ethanol access increased expression of MAFbx by 82% (p = 0.048), but did not robustly influence Akt-mTOR or UPP signaling. Daily wheel access did not prevent alcohol-induced MAFbx expression; however, ethanol access decreased the phosphorylation of p70S6K by 45% in running mice (p = 0.020). These results suggest that physical activity may be insufficient to prevent alcohol-induced changes to signaling factors along pathways involved in muscle loss. Instead, binge-patterned ethanol ingestion may impair the benefits of physical activity on factors involved in MPS.
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Affiliation(s)
- Carter H Reed
- Department of Kinesiology, Forker Building, 534 Wallace Road, Iowa State University, Ames, IA, 50011, United States; Interdepartmental Graduate Program of Nutritional Sciences, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States
| | - Trevor J Buhr
- Neuroscience Program, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Department of Food Science and Human Nutrition, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States
| | - Anna C Tystahl
- Department of Kinesiology, Forker Building, 534 Wallace Road, Iowa State University, Ames, IA, 50011, United States
| | - Ella E Bauer
- Interdepartmental Graduate Program of Nutritional Sciences, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Neuroscience Program, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Department of Food Science and Human Nutrition, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States
| | - Peter J Clark
- Interdepartmental Graduate Program of Nutritional Sciences, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Neuroscience Program, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Department of Food Science and Human Nutrition, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States.
| | - Rudy J Valentine
- Department of Kinesiology, Forker Building, 534 Wallace Road, Iowa State University, Ames, IA, 50011, United States; Interdepartmental Graduate Program of Nutritional Sciences, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States; Neuroscience Program, MacKay Hall, 2302 Osborn Drive, Iowa State University, Ames, IA, 50011, United States.
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Caceres-Ayala C, Pautassi RM, Acuña MJ, Cerpa W, Rebolledo DL. The functional and molecular effects of problematic alcohol consumption on skeletal muscle: a focus on athletic performance. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2022; 48:133-147. [PMID: 35389308 DOI: 10.1080/00952990.2022.2041025] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Background: Chronic alcohol misuse is associated with alcoholic myopathy, characterized by skeletal muscle weakness and atrophy. Moreover, there is evidence that sports-related people seem to exhibit a greater prevalence of problematic alcohol consumption, especially binge drinking (BD), which might not cause alcoholic myopathy but can negatively impact muscle function and amateur and professional athletic performance.Objective: To review the literature concerning the effects of alcohol consumption on skeletal muscle function and structure that can affect muscle performance.Methodology: We examined the currently available literature (PubMed, Google Scholars) to develop a narrative review summarizing the knowledge about the effects of alcohol on skeletal muscle function and exercise performance, obtained from studies in human beings and animal models for problematic alcohol consumption.Results: Exercise- and sport-based studies indicate that alcohol consumption can negatively affect muscle recovery after vigorous exercise, especially in men, while women seem less affected. Clinical studies and pre-clinical laboratory research have led to the knowledge of some of the mechanisms involved in alcohol-related muscle dysfunction, including an imbalance between anabolic and catabolic pathways, reduced regeneration, increased inflammation and fibrosis, and deficiencies in energetic balance and mitochondrial function. These pathological features can appear not only under chronic alcohol misuse but also in other alcohol consumption patterns.Conclusions: Most laboratory-based studies use chronic or acute alcohol exposure, while episodic BD, the most common drinking pattern in amateur and professional athletes, is underrepresented. Nevertheless, alcohol consumption negatively affects skeletal muscle health through different mechanisms, which collectively might contribute to reduced sports performance.
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Affiliation(s)
- Constanza Caceres-Ayala
- Centro de Excelencia En Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.,Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Ricardo M Pautassi
- Instituto de Investigación Médica M. Y M. Ferreyra, Inimec-Conicet, Universidad Nacional de Córdoba, Córdoba, Argentina.,Facultad de Psicología, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María José Acuña
- Facultad de Salud, Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O Higgins, Santiago, Chile.,Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Waldo Cerpa
- Centro de Excelencia En Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.,Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas Pontificia Universidad Católica de Chile, Santiago, Chile.,Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Daniela L Rebolledo
- Centro de Excelencia En Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.,Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
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Oudaert I, Satilmis H, Vlummens P, De Brouwer W, Maes A, Hose D, De Bruyne E, Ghesquière B, Vanderkerken K, De Veirman K, Menu E. Pyrroline-5-Carboxylate Reductase 1: a novel target for sensitizing multiple myeloma cells to bortezomib by inhibition of PRAS40-mediated protein synthesis. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2022; 41:45. [PMID: 35105345 PMCID: PMC8805317 DOI: 10.1186/s13046-022-02250-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 01/07/2022] [Indexed: 12/21/2022]
Abstract
Background Multiple myeloma (MM) remains an incurable cancer despite advances in therapy. Therefore, the search for new targets is still essential to uncover potential treatment strategies. Metabolic changes, induced by the hypoxic bone marrow, contribute to both MM cell survival and drug resistance. Pyrroline-5-carboxylate reductase 1 and 2 (PYCR1 and PYCR2) are two mitochondrial enzymes that facilitate the last step in the glutamine-to-proline conversion. Overexpression of PYCR1 is involved in progression of several cancers, however, its’ role in hematological cancers is unknown. In this study, we investigated whether PYCR affects MM viability, proliferation and response to bortezomib. Methods Correlation of PYCR1/2 with overall survival was investigated in the MMRF CoMMpass trial (653 patients). OPM-2 and RPMI-8226 MM cell lines were used to perform in vitro experiments. RPMI-8226 cells were supplemented with 13C-glutamine for 48 h in both normoxia and hypoxia (< 1% O2, by chamber) to perform a tracer study. PYCR1 was inhibited by siRNA or the small molecule inhibitor pargyline. Apoptosis was measured using Annexin V and 7-AAD staining, viability by CellTiterGlo assay and proliferation by BrdU incorporation. Differential protein expression was evaluated using Western Blot. The SUnSET method was used to measure protein synthesis. All in vitro experiments were performed in hypoxic conditions. Results We found that PYCR1 and PYCR2 mRNA expression correlated with an inferior overall survival. MM cells from relapsed/refractory patients express significantly higher levels of PYCR1 mRNA. In line with the strong expression of PYCR1, we performed a tracer study in RPMI-8226 cells, which revealed an increased conversion of 13C-glutamine to proline in hypoxia. PYCR1 inhibition reduced MM viability and proliferation and increased apoptosis. Mechanistically, we found that PYCR1 silencing reduced protein levels of p-PRAS40, p-mTOR, p-p70, p-S6, p-4EBP1 and p-eIF4E levels, suggesting a decrease in protein synthesis, which we also confirmed in vitro. Pargyline and siPYCR1 increased bortezomib-mediated apoptosis. Finally, combination therapy of pargyline with bortezomib reduced viability in CD138+ MM cells and reduced tumor burden in the murine 5TGM1 model compared to single agents. Conclusions This study identifies PYCR1 as a novel target in bortezomib-based combination therapies for MM. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02250-3.
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Nutritional Considerations for Injury Prevention and Recovery in Combat Sports. Nutrients 2021; 14:nu14010053. [PMID: 35010929 PMCID: PMC8746600 DOI: 10.3390/nu14010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/18/2021] [Accepted: 12/20/2021] [Indexed: 11/17/2022] Open
Abstract
Sports participation is not without risk, and most athletes incur at least one injury throughout their careers. Combat sports are popular all around the world, and about one-third of their injuries result in more than 7 days of absence from competition or training. The most frequently injured body regions are the head and neck, followed by the upper and lower limbs, while the most common tissue types injured are superficial tissues and skin, followed by ligaments and joint capsules. Nutrition has significant implications for injury prevention and enhancement of the recovery process due to its effect on the overall physical and psychological well-being of the athlete and improving tissue healing. In particular, amino acid and protein intake, antioxidants, creatine, and omega-3 are given special attention due to their therapeutic roles in preventing muscle loss and anabolic resistance as well as promoting injury healing. The purpose of this review is to present the roles of various nutritional strategies in reducing the risk of injury and improving the treatment and rehabilitation process in combat sports. In this respect, nutritional considerations for muscle, joint, and bone injuries as well as sports-related concussions are presented. The injury risk associated with rapid weight loss is also discussed. Finally, preoperative nutrition and nutritional considerations for returning to a sport after rehabilitation are addressed.
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Räisänen SE, Lage CFA, Zhou C, Melgar A, Silvestre T, Wasson DE, Cueva SF, Werner J, Takagi T, Miura M, Hristov AN. Lactational performance and plasma and muscle amino acid concentrations in dairy cows fed diets supplying 2 levels of digestible histidine and metabolizable protein. J Dairy Sci 2021; 105:170-187. [PMID: 34656346 DOI: 10.3168/jds.2021-20800] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 08/31/2021] [Indexed: 12/13/2022]
Abstract
The objective of this experiment was to investigate the effect of dietary levels of digestible histidine (dHis) and MP on lactational performance and plasma and muscle concentrations of free AA in dairy cows. A randomized block design experiment was conducted with 48 Holstein cows, including 20 primiparous, averaging (±SD) 103 ± 22 d in milk and 45 ± 9 kg/d milk yield at the beginning of the experiment. A 2-wk covariate period preceded 12 experimental wk, of which 10 wk were for data and sample collection. Experimental treatments were (1) MP-adequate (MPA) diet with 2.1% dHis of MP (MPA2.1), (2) MPA with 3.0% dHis (MPA3.0), (3) MP-deficient (MPD) diet with 2.1% dHis (MPD2.1), and (4) MPD with 3.0% dHis (MPD3.0). Actual dHis supply was estimated at 64, 97, 57, and 88 g/d, respectively. Diets supplied MP at 110% (MPA) and 96% (MPD) of NRC 2001 dairy model requirements calculated based on DMI and production data during the experiment. Dry matter intake and milk yield data were collected daily, milk samples for composition and blood samples for AA analysis were collected every other week, and muscle biopsies at the end of covariate period, and during wk 12 of the experiment. The overall DMI was not affected by dHis or MP level. Milk yield tended to be increased by 3.0% dHis compared with 2.1% dHis. Milk true protein concentration and yield were not affected by treatments, whereas milk urea nitrogen concentration was lower for MPD versus the MPA diet. Milk fat concentration was lower for MPD versus MPA. There was a MP × dHis interaction for milk fat yield and energy-corrected milk; milk fat was lower for MPD3.0 versus MPD2.1, but similar for cows fed the MPA diet regardless of dHis level whereas energy-corrected milk was greater for MPA3.0 versus MPA2.1 but tended to be lower for MPD3.0 versus MPD2.1. Plasma His concentration was greater for cows fed dHis3.0, and concentration of sum of essential AA was greater, whereas carnosine, 1-Methyl-His and 3-Methyl-His concentrations were lower for cows fed MPA versus MPD diet. Muscle concentration of His was greater for cows fed dHis3.0 treatment. The apparent efficiency of His utilization was increased at lower MP and His levels. Overall, cows fed a corn silage-based diet supplying MP at 110% of NRC (2001) requirements tended to have increased ECM yield and similar milk protein yield to cows fed a diet supplying MP at 96% of requirements. Supplying dHis at 3.0% of MP (or 86 and 96 g/d, for MPD3.0 and MPA3.0, respectively) tended to increase milk yield and increased plasma and muscle concentrations of His but had minor or no effects on other production variables in dairy cows.
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Affiliation(s)
- S E Räisänen
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - C F A Lage
- Department of Animal Science, The Pennsylvania State University, University Park 16802; School of Veterinary Medicine, University of California, Tulare 93274
| | - C Zhou
- Department of Animal Science, The Pennsylvania State University, University Park 16802; University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - A Melgar
- Department of Animal Science, The Pennsylvania State University, University Park 16802; Agricultural Innovation Institute of Panama (IDIAP), City of Knowledge 07144, Panama
| | - T Silvestre
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - D E Wasson
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - S F Cueva
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - J Werner
- Animal Resource Program, The Pennsylvania State University, University Park 16802
| | - T Takagi
- Ajinomoto Co. Inc., Kawasaki, Japan 210-8681
| | - M Miura
- Ajinomoto Co. Inc., Kawasaki, Japan 210-8681
| | - A N Hristov
- Department of Animal Science, The Pennsylvania State University, University Park 16802.
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10
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Sarcopenia-The Impact on Physical Capacity of Liver Transplant Patients. Life (Basel) 2021; 11:life11080740. [PMID: 34440484 PMCID: PMC8401329 DOI: 10.3390/life11080740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/07/2021] [Accepted: 07/19/2021] [Indexed: 01/10/2023] Open
Abstract
Optimizing patients' condition before liver transplantation (LT) could potentially improve survival of LT patients. We focused on sarcopenia, as a common factor in liver transplant candidates that can impact their cardiopulmonary performance at the point of listing, morbidity, and mortality after LT. We performed a single-center cohort study on 98 consecutive patients with liver cirrhosis who were transplanted between March 2015 and December 2017. The third lumbar vertebra skeletal muscle index (L3SMI) was calculated using CT imaging to distinguish sarcopenia at listing for LT. Data regarding liver function, body mass index (BMI), cardiac biomarkers, the peak oxygen uptake (VO2) and LT outcome were collected and correlated to L3SMI. For data analysis the Dell Statistica (Version 13. Dell Inc., Rondrock, TX, USA) was used. In total, 98 cirrhotic patients were included. Fifty-five (56.1%) patients, mostly males, had sarcopenia according to L3SMI, with the lowest L3SMI in males with alcohol-related liver disease. Lower L3SMI correlated with lower BMI, lower VO2 peak, and higher NTproBNP (all p < 0.001) and revealed an essential correlation with prolonged ICU stay (r = -0.21, p < 0.05). 33 patients were unable to perform cardio-pulmonary exercise test, mostly sarcopenic (67%), with more advanced liver insufficiency (assessed with CPC and MELD scores) and longer stay at ICU after LT (all p < 0.001). Sarcopenia was common among LT recipients. It was associated with inferior result in cardio-pulmonary performance before LT and prolonged ICU stay after grafting.
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Laufenberg LJ, Crowell KT, Lang CH. Alcohol Acutely Antagonizes Refeeding-Induced Alterations in the Rag GTPase-Ragulator Complex in Skeletal Muscle. Nutrients 2021; 13:1236. [PMID: 33918604 PMCID: PMC8070399 DOI: 10.3390/nu13041236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/17/2021] [Accepted: 04/02/2021] [Indexed: 02/07/2023] Open
Abstract
The Ragulator protein complex is critical for directing the Rag GTPase proteins and mTORC1 to the lysosome membrane mediating amino acid-stimulated protein synthesis. As there is a lack of evidence on alcohol's effect on the Rag-Ragulator complex as a possible mechanism for the development of alcoholic skeletal muscle wasting, the aim of our study was to examine alterations in various protein-protein complexes in the Rag-Ragulator pathway produced acutely by feeding and how these are altered by alcohol under in vivo conditions. Mice (C57Bl/6; adult males) were fasted, and then provided rodent chow for 30 min ("refed") or remained food-deprived ("fasted"). Mice subsequently received ethanol (3 g/kg ethanol) or saline intraperitoneally, and hindlimb muscles were collected 1 h thereafter for analysis. Refeeding-induced increases in myofibrillar and sarcoplasmic protein synthesis, and mTOR and S6K1 phosphorylation, were prevented by alcohol. This inhibition was not associated with a differential rise in the intracellular leucine concentration or plasma leucine or insulin levels. Alcohol increased the amount of the Sestrin1•GATOR2 complex in the fasted state and prevented the refeeding-induced decrease in Sestrin1•GATOR2 seen in control mice. Alcohol antagonized the increase in the RagA/C•Raptor complex formation seen in the refed state. Alcohol antagonized the increase in Raptor with immunoprecipitated LAMPTOR1 (part of the Ragulator complex) after refeeding and decreased the association of RagC with LAMPTOR1. Finally, alcohol increased the association of the V1 domain of v-ATPase with LAMPTOR1 and prevented the refeeding-induced decrease in v-ATPase V1 with LAMPTOR1. Overall, these data demonstrate that acute alcohol intake disrupts multiple protein-protein complexes within the Rag-Ragulator complex, which are associated with and consistent with the concomitant decline in nutrient-stimulated muscle protein synthesis under in vivo conditions.
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Affiliation(s)
- Lacee J. Laufenberg
- Department of Surgery, Penn State College of Medicine, Hershey, PA 17033, USA; (L.J.L.); (K.T.C.)
| | - Kristen T. Crowell
- Department of Surgery, Penn State College of Medicine, Hershey, PA 17033, USA; (L.J.L.); (K.T.C.)
- Beth Israel Deaconess Medical Center, Department of Surgery, Boston, MA 02215, USA
| | - Charles H. Lang
- Department of Surgery, Penn State College of Medicine, Hershey, PA 17033, USA; (L.J.L.); (K.T.C.)
- Department of Cellular & Molecular Physiology, Penn State College of Medicine, Hershey, PA 17033, USA
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12
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Langer HT, Mossakowski AA, Pathak S, Mascal M, Baar K. Cannabidiol Does Not Impair Anabolic Signaling Following Eccentric Contractions in Rats. Int J Sport Nutr Exerc Metab 2021; 31:93-100. [PMID: 33621949 DOI: 10.1123/ijsnem.2020-0270] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/17/2020] [Accepted: 11/17/2020] [Indexed: 11/18/2022]
Abstract
Cannabidiol (CBD) has proven clinical benefits in the treatment of seizures, inflammation, and pain. The recent legalization of CBD in many countries has caused increased interest in the drug as an over-the-counter treatment for athletes looking to improve recovery. However, no data on the effects of CBD on the adaptive response to exercise in muscle are available. To address this gap, we eccentrically loaded the tibialis anterior muscle of 14 rats, injected them with a vehicle (n = 7) or 100 mg/kg CBD (n = 7), and measured markers of injury, inflammation, anabolic signaling, and autophagy 18 hr later. Pro-inflammatory signaling through nuclear factor kappa B (NF-kB) (Ser536) increased with loading in both groups; however, the effect was significantly greater (36%) in the vehicle group (p < .05). Simultaneously, anabolic signaling through ribosomal protein S6 kinase beta-1 (S6K1) (Thr389) increased after eccentric contractions in both groups with no difference between vehicle and CBD (p = .66). The ribosomal protein S6 phosphorylation (240/244) increased with stimulation (p < .001) and tended to be higher in the CBD group (p = .09). The ubiquitin-binding protein p62 levels were not modulated by stimulation (p = .6), but they were 46% greater in the CBD compared with the vehicle group (p = .01). Although liver weight did not differ between the groups (p = .99) and levels of proteins associated with stress were similar, we did observe serious side effects in one animal. In conclusion, an acute dose of CBD decreased pro-inflammatory signaling in the tibialis anterior without blunting the anabolic response to exercise in rats. Future research should determine whether these effects translate to improved recovery without altering adaptation in humans.
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Affiliation(s)
| | | | | | | | - Keith Baar
- University of California
- VA Northern California Health Care System
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13
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Takegaki J, Ogasawara R, Kouzaki K, Fujita S, Nakazato K, Ishii N. The distribution of eukaryotic initiation factor 4E after bouts of resistance exercise is altered by shortening of recovery periods. J Physiol Sci 2020; 70:54. [PMID: 33148163 PMCID: PMC10717013 DOI: 10.1186/s12576-020-00781-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 10/22/2020] [Indexed: 11/10/2022]
Abstract
Insufficient duration of recovery between resistance exercise bouts reduces the effects of exercise training, but the influence on muscle anabolic responses is not fully understood. Here, we investigated the changes in the distribution of eukaryotic initiation factor (eIF) 4E, a key regulator of translation initiation, and related factors in mouse skeletal muscle after three successive bouts of resistance exercise with three durations of recovery periods (72 h: conventional, 24 h: shorter, and 8 h: excessively shorter). Bouts of resistance exercise dissociated eIF4E from eIF4E binding protein 1, with the magnitude increasing with shorter recovery. Whereas bouts of resistance exercise with 72 h recovery increased the association of eIF4E and eIF4G, those with shorter recovery did not. Similar results were observed in muscle protein synthesis. These results suggest that insufficient recovery inhibited the association of eIF4E and eIF4G, which might cause attenuation of protein synthesis activation after bouts of resistance exercise.
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Affiliation(s)
- Junya Takegaki
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
- Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga, 525-8577, Japan.
| | - Riki Ogasawara
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Nagoya, Japan
| | - Karina Kouzaki
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Satoshi Fujita
- Faculty of Sport and Health Science, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Koichi Nakazato
- Graduate School of Health and Sport Science, Nippon Sport Science University, Tokyo, Japan
| | - Naokata Ishii
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
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Translation Regulation by eIF2α Phosphorylation and mTORC1 Signaling Pathways in Non-Communicable Diseases (NCDs). Int J Mol Sci 2020; 21:ijms21155301. [PMID: 32722591 PMCID: PMC7432514 DOI: 10.3390/ijms21155301] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/20/2020] [Accepted: 07/22/2020] [Indexed: 02/07/2023] Open
Abstract
Non-communicable diseases (NCDs) are medical conditions that, by definition, are non-infectious and non-transmissible among people. Much of current NCDs are generally due to genetic, behavioral, and metabolic risk factors that often include excessive alcohol consumption, smoking, obesity, and untreated elevated blood pressure, and share many common signal transduction pathways. Alterations in cell and physiological signaling and transcriptional control pathways have been well studied in several human NCDs, but these same pathways also regulate expression and function of the protein synthetic machinery and mRNA translation which have been less well investigated. Alterations in expression of specific translation factors, and disruption of canonical mRNA translational regulation, both contribute to the pathology of many NCDs. The two most common pathological alterations that contribute to NCDs discussed in this review will be the regulation of eukaryotic initiation factor 2 (eIF2) by the integrated stress response (ISR) and the mammalian target of rapamycin complex 1 (mTORC1) pathways. Both pathways integrally connect mRNA translation activity to external and internal physiological stimuli. Here, we review the role of ISR control of eIF2 activity and mTORC1 control of cap-mediated mRNA translation in some common NCDs, including Alzheimer’s disease, Parkinson’s disease, stroke, diabetes mellitus, liver cirrhosis, chronic obstructive pulmonary disease (COPD), and cardiac diseases. Our goal is to provide insights that further the understanding as to the important role of translational regulation in the pathogenesis of these diseases.
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15
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Abstract
Both acute intoxication and longer-term cumulative ingestion of alcohol negatively impact the metabolic phenotype of both skeletal and cardiac muscle, independent of overt protein calorie malnutrition, resulting in loss of skeletal muscle strength and cardiac contractility. In large part, these alcohol-induced changes are mediated by a decrease in protein synthesis that in turn is governed by impaired activity of a protein kinase, the mechanistic target of rapamycin (mTOR). Herein, we summarize recent advances in understanding mTOR signal transduction, similarities and differences between the effects of alcohol on this central metabolic controller in skeletal muscle and in the heart, and the effects of acute versus chronic alcohol intake. While alcohol-induced alterations in global proteolysis via activation of the ubiquitin-proteasome pathway are equivocal, emerging data suggest alcohol increases autophagy in muscle. Further studies are necessary to define the relative contributions of these bidirectional changes in protein synthesis and autophagy in the etiology of alcoholic myopathy in skeletal muscle and the heart.
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Affiliation(s)
- Scot R Kimball
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA; ,
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA; ,
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16
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Discovery of NV-5138, the first selective Brain mTORC1 activator. Sci Rep 2019; 9:4107. [PMID: 30858438 PMCID: PMC6412019 DOI: 10.1038/s41598-019-40693-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 02/20/2019] [Indexed: 12/21/2022] Open
Abstract
The mechanistic target of rapamycin complex 1 (mTORC1) has been linked to several important chronic medical conditions many of which are associated with advancing age. A variety of inputs including the amino acid leucine are required for full mTORC1 activation. The cytoplasmic proteins Sestrin1 and Sestrin2 specifically bind to the multiprotein complex GATOR2 and communicate leucine sufficiency to the mTORC1 pathway activation complex. Herein, we report NV-5138, a novel orally bioavailable compound that binds to Sestrin2 and activates mTORC1 both in vitro and in vivo. NV-5138 like leucine transiently activates mTORC1 in several peripheral tissues, but in contrast to leucine uniquely activates this complex in the brain due lack of metabolism and utilization in protein synthesis. As such, NV-5138 will permit the exploration in areas of unmet medical need including neuropsychiatric conditions and cognition which have been linked to the activation status of mTORC1.
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17
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Leucine regulates α-amylase and trypsin synthesis in dairy calf pancreatic tissue in vitro via the mammalian target of rapamycin signalling pathway. Animal 2019; 13:1899-1906. [DOI: 10.1017/s1751731118003683] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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18
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Bhanji RA, Narayanan P, Moynagh MR, Takahashi N, Angirekula M, Kennedy CC, Mara KC, Dierkhising RA, Watt KD. Differing Impact of Sarcopenia and Frailty in Nonalcoholic Steatohepatitis and Alcoholic Liver Disease. Liver Transpl 2019; 25:14-24. [PMID: 30257063 PMCID: PMC7187989 DOI: 10.1002/lt.25346] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/05/2018] [Indexed: 12/12/2022]
Abstract
Sarcopenia and frailty are commonly encountered in patients with end-stage liver disease and are associated with adverse clinical outcomes, including decompensation and wait-list mortality. The impact of these entities in patients with differing disease etiologies has not been elucidated. We aim to ascertain the change in their prevalence over time on the wait list and determine their impact on hospitalization, delisting, and wait-list survival, specifically for patients with nonalcoholic steatohepatitis (NASH) and alcoholic liver disease (ALD). Adult patients who were evaluated for their first liver transplant from 2014 to 2016 with a primary diagnosis of NASH (n = 136) or ALD (n = 129) were included. Computed tomography scans were used to determine the presence of sarcopenia and myosteatosis. Frailty was diagnosed using the Rockwood frailty index. Patients with NASH had a significantly lower prevalence of sarcopenia (22% versus 47%; P < 0.001) but a significantly higher prevalence of frailty (49% versus 34%; P = 0.03) when compared with patients with ALD at the time of listing. In patients with NASH, sarcopenia was not associated with adverse events, but a higher frailty score was associated with an increased length of hospitalization (P = 0.05) and an increased risk of delisting (P = 0.02). In patients with ALD, univariate analysis showed the presence of sarcopenia was associated with an increased risk of delisting (P = 0.01). In conclusion, sarcopenia and frailty occur with differing prevalence with variable impact on outcomes in wait-listed patients with NASH and ALD.
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Affiliation(s)
- Rahima A. Bhanji
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
| | | | | | | | | | - Cassie C. Kennedy
- Division of Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, MN
| | - Kristin C. Mara
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - Ross A. Dierkhising
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN
| | - Kymberly D. Watt
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
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Ethanol acutely antagonizes the refeeding-induced increase in mTOR-dependent protein synthesis and decrease in autophagy in skeletal muscle. Mol Cell Biochem 2018; 456:41-51. [PMID: 30523512 DOI: 10.1007/s11010-018-3488-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 11/30/2018] [Indexed: 12/28/2022]
Abstract
The purpose of this study was to determine the impact of acute ethanol administration on the major signal transduction pathways in skeletal muscle responsible for regulating the protein synthetic and degradative response to refeeding. Adult male C57Bl/6 mice were fasted overnight; mice were then either refed normal rodent chow for 30 min or a separate group of mice remained food deprived (i.e., fasted). Thereafter, mice were administered either 3 g/kg ethanol or saline. Gastrocnemius/plantaris was collected 1 h later and analyzed. Acute ethanol decreased basal and prevented the refeeding-induced increase in muscle protein synthesis. While ethanol prevented a nutrient-stimulated increase in S6K1 phosphorylation, it did not alter the increase in 4E-BP1 phosphorylation. Downstream of S6K1, ethanol also attenuated the refeeding-induced increase in S6 and eIF4B phosphorylation, as well as the decrease in eEF2 phosphorylation. Although ethanol decreased ERK and p90 RSK phosphorylation, activation of this signaling pathway was not altered by refeeding in either control or ethanol-treated mice. Related to protein degradation, in vitro-determined proteasome activity and the content of total ubiquitinated proteins were not altered by ethanol and/or refeeding. Control mice appeared to exhibit a refeeding-induced decrease in autophagy as suggested by the increased FoxO3 and ULK1 phosphorylation and total p62 protein as well as decreased LC3B-II; however, ethanol blunted these refeeding-induced changes. These data suggest that ethanol can acutely prevent the normally observed mTOR-dependent increase in protein synthesis and reduction in autophagy in response to nutrient stimulation, but does not appear to acutely alter proteasome activity.
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20
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Lang CH. Lack of sexual dimorphism on the inhibitory effect of alcohol on muscle protein synthesis in rats under basal conditions and after anabolic stimulation. Physiol Rep 2018; 6:e13929. [PMID: 30512248 PMCID: PMC6278815 DOI: 10.14814/phy2.13929] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/25/2018] [Accepted: 10/26/2018] [Indexed: 11/24/2022] Open
Abstract
Previous studies indicate women have a higher blood alcohol (i.e., ethanol) and acetaldehyde concentration after consuming an equivalent amount of alcohol, and that women are more susceptible to the long-term negative health effects of alcohol. However, there is a paucity of data pertaining to whether there is a sexual dimorphic response in skeletal muscle to alcohol. Adult male and female Sprague-Dawley rats were used and the primary endpoint was in vivo determined muscle (gastrocnemius) protein synthesis (MPS). The initial study indicated MPS did not differ in female rats during proestrus, estrus, metestrus, or diestrus; hence, subsequent studies used female rats irrespective of estrus cycle phase. There was no difference in MPS between male and female rats under basal fasted conditions, and the time- and dose-responsiveness of both groups to the inhibitory effect of acute alcohol did not differ. The ability of alcohol to suppress MPS was comparable in male and female rats pretreated with alcohol dehydrogenase inhibitor 4-methylpyrazol. Chronic alcohol feeding for 6 weeks decreased MPS in male but not in female rats; however, MPS was reduced in both sexes at 14 weeks. Finally, oral gavage of leucine increased MPS similarly in male and female rats and chronic alcohol feeding for 14 weeks prevented the anabolic effect in both sexes. These data suggest normal fluctuations in ovarian hormones do not significantly alter MPS in female rats, and that there is no sexual dimorphic response to the effects of acute alcohol intoxication on MPS. While chronic alcohol consumption appeared to decrease MPS at an early time point in male compared to female rats, there was no sex difference in the suppressive effect of alcohol at a later time point. Overall, these data do not support the prevailing belief that females are more susceptible than males to alcohol's catabolic effect on MPS.
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Affiliation(s)
- Charles H. Lang
- Department of Cellular and Molecular PhysiologyPenn State College of MedicineHersheyPennsylvania
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21
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Mekheal M, Steiner JL, Lang CH. Acute alcohol prevents the refeeding-induced decrease in autophagy but does not alter the increased protein synthetic response in heart. Alcohol 2018; 73:79-88. [PMID: 30316145 DOI: 10.1016/j.alcohol.2018.04.005] [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: 03/20/2018] [Revised: 04/12/2018] [Accepted: 04/13/2018] [Indexed: 02/02/2023]
Abstract
Ethanol produces a state of anabolic resistance in skeletal muscle; however, whether the heart displays a similar defect is unknown. Hence, the purpose of this study was to determine the impact of acute ethanol administration on the major signal transduction pathways in the heart that are responsible for regulating the protein synthetic and degradative response to refeeding. Adult male C57Bl/6 mice were fasted for 12 h. Mice were then either refed normal rodent chow for 30 min or a separate group of mice remained food deprived prior to administration of 3-g/kg ethanol. Cardiac tissue and blood were collected 1 h thereafter and analyzed. Acute ethanol prevented the nutrient-induced stimulation of S6K1 phosphorylation in heart, but did not alter the phosphorylation of S6, eIF4B, and eEF2, known downstream substrates for this kinase. The refeeding-induced redistribution of eIF4E into the active eIF4F complex was also not changed by acute ethanol. Consistent with the above-mentioned changes in signaling proteins, ethanol did not impair the refeeding-induced increase in cardiac protein synthesis. Proteasome activity was not altered by alcohol and/or refeeding. In contrast, ethanol antagonized the refeeding-induced increase in ULK1 phosphorylation and p62 as well as the reduction in LC3B-II and Atg5/12 complex proteins. These data indicate that acute ethanol prevents the normally observed inhibition of autophagy seen after refeeding, while the mTOR-dependent increase in protein synthesis remains largely unaltered by alcohol.
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Phenylalanine regulates initiation of digestive enzyme mRNA translation in pancreatic acinar cells and tissue segments in dairy calves. Biosci Rep 2018; 38:BSR20171189. [PMID: 29263147 PMCID: PMC5784178 DOI: 10.1042/bsr20171189] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 12/14/2017] [Accepted: 12/20/2017] [Indexed: 01/13/2023] Open
Abstract
As new nutritional strategies for ruminant are designed to change production efficiency by improving the supply of rumen protect protein, lipid, and even starch, the digestive system must fit to utilize these increased nutrient supplies, especially the pancreas. The objective of this study was to investigate the effects of phenylalanine (Phe) on digestive enzymes synthesis or secretion and cellular signaling in pancreatic acinar (PA) cells of dairy calves. The PA cells isolated from fresh pancreas of dairy calves, and cultured in completed RIPA 1640 medium with no fetal serum but 0, 0.15 and 0.45 mM Phe at 37°C in CO2 incubator for 120 min. The pancreatic tissue segments (PTS) was cut approximately 2 × 2 mm from the fresh pancreas, and incubated in oxygenated Krebs-Ringer bicarbonate (KRB) buffer containing 0 or 0.35 mM Phe at 39°C for 180 min, and the samples were collected every 60 min after incubation. In PA cells, Phe increased (P < 0.05) the α-amylase secretion and mRNA expression, the phosphorylation of ribosomal protein S6 kinase 1 (S6K1) and eukaryotic initiation factor 4E binding protein 1 (4EBP1). In PTS, the Phe increased (P < 0.05) α-amylase and trypsin synthesis, secretion and mRNA expression, as well as the phosphorylation of S6K1 and 4EBP1. Conclusively, these results suggested that Phe regulates the synthesis or secretion of α-amylase, trypsin and lipase through mRNA translation initiation factors – S6K1 and 4EBP1.
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Abstract
As the cirrhosis progresses, development of complication like ascites, hepatic encephalopathy, variceal bleeding, kidney dysfunction, and hepatocellular carcinoma signify increasing risk of short term mortality. Malnutrition and muscle wasting (sarcopenia) is yet other complications that negatively impact survival, quality of life, and response to stressors, such as infection and surgery in patients with cirrhosis. Conventionally, these are not routinely looked for, because nutritional assessment can be a difficult especially if there is associated fluid retention and/or obesity. Patients with cirrhosis may have a combination of loss of skeletal muscle and gain of adipose tissue, culminating in the condition of "sarcopenic obesity." Sarcopenia in cirrhotic patients has been associated with increased mortality, sepsis complications, hyperammonemia, overt hepatic encephalopathy, and increased length of stay after liver transplantation. Assessment of muscles with cross-sectional imaging studies has become an attractive index of nutritional status evaluation in cirrhosis, as sarcopenia, the major component of malnutrition, is primarily responsible for the adverse clinical consequences seen in patients with liver disease. Cirrhosis is a state of accelerated starvation, with increased gluconeogenesis that requires amino acid diversion from other metabolic functions. Protein homeostasis is disturbed in cirrhosis due to several factors such as hyperammonemia, hormonal, and cytokine abnormalities, physical inactivity and direct effects of ethanol and its metabolites. New approaches to manage sarcopenia are being evolved. Branched chain amino acid supplementation, Myostatin inhibitors, and mitochondrial protective agents are currently in various stages of evaluation in preclinical studies to prevent and reverse sarcopenia, in cirrhosis.
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Key Words
- (PG) SGA, patient-generated SGA
- AMPK, 5′ adenosine monophosphate-activated protein kinase
- ASPEN, American Society of Parenteral and Enteral Nutrition
- ATP, adenosine triphosphate
- Akt/PKB, serine/threonine-specific protein kinase B
- BIA, bio-electric impedance analysis
- BMC, bone mineral content
- BMI, body mass index
- CT, computed tomography
- DDLT, deceased donor liver transplantation
- DRM, disease-related malnutrition
- DXA, dual X-ray absorptiometry
- ESPEN, European Society of Parenteral and Enteral Nutrition
- FFI, Fried Frailty Index
- FFM, fat free mass
- FFMI, fat free mass index
- FM, fat mass
- HE, hepatic encephalopathy
- LDLT, living donor liver transplant
- LST, lean soft tissue
- MAC, mid arm circumference
- MAMC, mid arm muscle circumference
- MELD, model for end-stage liver disease
- MNA, Mini Nutritional Assessment
- MRI, magnetic resonance imaging
- NASH, non-alcoholic steatohepatitis
- PCM, protein-calorie nalnutrition
- REE, resting energy expenditure
- RQ, respiratory quotient (or RQ or respiratory coefficient)
- SGA, Subjective Global Assessment
- SMI, Skeletal Muscle Index
- SPPB, Short Physical Performance Battery
- TIPS, trans jugular intrahepatic portocaval shunts
- TNF, tumour necrosis factor
- TSF, triceps skin fild thickness
- WHO, World Health Organisation
- YPA, total psoas area
- aKG, alfa keto glutarate
- cirrhosis
- mTORC1, mammalian target of rapamycin complex 1
- nutrition
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Shenkman BS, Belova SP, Zinovyeva OE, Samkhaeva ND, Mirzoev TM, Vilchinskaya NA, Altaeva EG, Turtikova OV, Kostrominova TY, Nemirovskaya TL. Effect of Chronic Alcohol Abuse on Anabolic and Catabolic Signaling Pathways in Human Skeletal Muscle. Alcohol Clin Exp Res 2017; 42:41-52. [PMID: 29044624 DOI: 10.1111/acer.13531] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 10/10/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Animal studies showed that alcoholic myopathy is characterized by the reduction in myofiber cross-sectional area (CSA) and by impaired anabolic signaling. The goal of this study was to compare changes in CSA and fiber type composition with modifications in anabolic and catabolic signaling pathways at the early stages of alcohol misuse in humans. METHODS Skeletal muscle samples from 7 male patients with chronic alcohol abuse (AL; 47.7 ± 2.0 years old; alcohol misuse duration 7.7 ± 0.6 years) were compared with muscle from a control group of 7 healthy men (C; 39.7 ± 5.0 years old). Biopsies from vastus lateralis muscles were taken and analyzed for the changes in fiber type composition, fiber CSA, and for the alterations in anabolic and catabolic signaling pathways. RESULTS AL patients did not have detectable clinical myopathy symptoms or muscle fiber atrophy, but the relative proportion of fast fibers was increased. There was a significant decrease in IGF-1 in plasma and IRS-1 protein content in muscle of AL group. Levels of total and phosphorylated p70S6K1, GSK3β, and p90RSK1 were not different between AL and C groups. Muscle of AL patients had increased mRNA expression of HSP70 and HSP90. A marker of anabolic pathway p-4E-BP1 was decreased, while catabolic markers (MuRF-1, MAFbx, ubiquitinated proteins) were increased in AL patients when compared with C group. CONCLUSIONS At the early stages of alcohol misuse in humans, changes in the regulation of anabolic and catabolic signaling pathways precede the development of skeletal muscle atrophy and manifestation of clinical symptoms of alcoholic myopathy.
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Affiliation(s)
| | | | - Olga E Zinovyeva
- Sechenov First Moscow State Medical University, Russian Ministry of Health, Moscow, Russia
| | - Nudlya D Samkhaeva
- Sechenov First Moscow State Medical University, Russian Ministry of Health, Moscow, Russia
| | | | | | | | | | - Tatiana Y Kostrominova
- Department of Anatomy and Cell Biology, Indiana University School of Medicine Northwest, Gary, Indiana
| | - Tatiana L Nemirovskaya
- Institute of Biomedical Problems, RAS, Moscow, Russia.,Faculty of Basic Medicine, Lomonosov Moscow State University, Moscow, Russia
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Dasarathy J, McCullough AJ, Dasarathy S. Sarcopenia in Alcoholic Liver Disease: Clinical and Molecular Advances. Alcohol Clin Exp Res 2017; 41:1419-1431. [PMID: 28557005 DOI: 10.1111/acer.13425] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 05/16/2017] [Indexed: 12/18/2022]
Abstract
Despite advances in treatment of alcohol use disorders that focus on increasing abstinence and reducing recidivism, alcoholic liver disease (ALD) is projected to be the major cause of cirrhosis and its complications. Malnutrition is recognized as the most frequent complication in ALD, and despite the high clinical significance, there are no effective therapies to reverse malnutrition in ALD. Malnutrition is a relatively imprecise term, and sarcopenia or skeletal muscle loss, the major component of malnutrition, is primarily responsible for the adverse clinical consequences in patients with liver disease. It is, therefore, critical to define the specific abnormality (sarcopenia) rather than malnutrition in ALD, so that therapies targeting sarcopenia can be developed. Skeletal muscle mass is maintained by a balance between protein synthesis and proteolysis. Both direct effects of ethanol (EtOH) and its metabolites on the skeletal muscle and the consequences of liver disease result in disturbed proteostasis (protein homeostasis) and consequent sarcopenia. Once cirrhosis develops in patients with ALD, abstinence is unlikely to be effective in completely reversing sarcopenia, as other contributors including hyperammonemia, hormonal, and cytokine abnormalities aggravate sarcopenia and maintain a state of anabolic resistance initiated by EtOH. Cirrhosis is also a state of accelerated starvation, with increased gluconeogenesis that requires amino acid diversion from signaling and substrate functions. Novel therapeutic options are being recognized that are likely to supplant the current "deficiency replacement" approach and instead focus on specific molecular perturbations, given the increasing availability of small molecules that can target specific signaling components. Myostatin antagonists, leucine supplementation, and mitochondrial protective agents are currently in various stages of evaluation in preclinical studies to prevent and reverse sarcopenia, in cirrhosis in general, and ALD, specifically. Translation of these data to human studies and clinical application requires priority for allocation of resources.
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Affiliation(s)
| | - Arthur J McCullough
- Department of Gastreoenterology, Hepatology and Pathobiology, Cleveland Clinic, Cleveland, Ohio
| | - Srinivasan Dasarathy
- Department of Gastreoenterology, Hepatology and Pathobiology, Cleveland Clinic, Cleveland, Ohio
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Steiner JL, Lang CH. Alcoholic Cardiomyopathy: Disrupted Protein Balance and Impaired Cardiomyocyte Contractility. Alcohol Clin Exp Res 2017; 41:1392-1401. [PMID: 28425109 DOI: 10.1111/acer.13405] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Accepted: 04/12/2017] [Indexed: 12/29/2022]
Abstract
Alcoholic cardiomyopathy (ACM) can develop after consumption of relatively large amounts of alcohol over time or from acute binge drinking. Of the many factors implicated in the etiology of ACM, chronic perturbation in protein balance has been strongly implicated. This review focused on recent contributions (since 2010) in the area of protein metabolism and cardiac function related to ACM. Data reviewed include that from in vitro and preclinical in vivo animal studies where alcohol or an oxidative metabolite was studied and outcome measures in either cardiomyocytes or whole heart pertaining to protein synthesis or degradation were reported. Additionally, studies on the contractile properties of cardiomyocytes were also included to link signal transduction with function. Methodological differences including the potential impact of sex, dosing, and duration/timing of alcohol administration are addressed. Acute and chronic alcohol consumption decreases cardiac protein synthesis and/or activation of proteins within the regulatory mammalian/mechanistic target of rapamycin complex pathway. Albeit limited, evidence suggests that myocardial protein degradation via the ubiquitin pathway is not altered, while autophagy may be enhanced in ACM. Alcohol impairs ex vivo cardiomyocyte contractility in relation to its metabolism and expression of proteins within the growth factor pathway. Dysregulation of protein metabolism, including the rate of protein synthesis and autophagy, may contribute to contractile deficits and is a hallmark feature of ACM meriting additional sex-inclusive, methodologically consistent studies.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
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Duplanty AA, Budnar RG, Luk HY, Levitt DE, Hill DW, McFarlin BK, Huggett DB, Vingren JL. Effect of Acute Alcohol Ingestion on Resistance Exercise-Induced mTORC1 Signaling in Human Muscle. J Strength Cond Res 2017; 31:54-61. [PMID: 27135475 DOI: 10.1519/jsc.0000000000001468] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Duplanty, AA, Budnar, RG, Luk, HY, Levitt, DE, Hill, DW, McFarlin, BK, Huggett, DB, and Vingren, JL. Effect of acute alcohol ingestion on resistance exercise-induced mTORC1 signaling in human muscle. J Strength Cond Res 31(1): 54-61, 2017-The purpose of this project was to further elucidate the effects postexercise alcohol ingestion. This project had many novel aspects including using a resistance exercise (RE) only exercise design and the inclusion of women. Ten resistance-trained males and 9 resistance-trained females completed 2 identical acute heavy RE trials (6 sets of Smith machine squats) followed by ingestion of either alcohol or placebo. All participants completed both conditions. Before exercise (PRE) and 3 (+3 hours) and 5 (+5 hours) hours postexercise, muscle tissue samples were obtained from the vastus lateralis by biopsies. Muscle samples were analyzed for phosphorylated mTOR, S6K1, and 4E-BP1. For men, there was a significant interaction effect for mTOR and S6K1 phosphorylation. At +3 hours, mTOR and S6K1 phosphorylation was higher for placebo than for alcohol. For women, there was a significant main effect for time. mTOR phosphorylation was higher at +3 hours than at PRE and at +5 hours. There were no significant effects found for 4E-BP1 phosphorylation in men or women. The major findings of this study was that although RE elicited similar mTORC1 signaling both in men and in women, alcohol ingestion seemed to only attenuate RE-induced phosphorylation of the mTORC1 signaling pathway in men. This study provides evidence that alcohol should not be ingested after RE as this ingestion could potentially hamper the desired muscular adaptations to RE by reducing anabolic signaling, at least in men.
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Affiliation(s)
- Anthony A Duplanty
- 1Applied Physiology Laboratory, Department of Kinesiology, Health Promotion, and Recreation, University of North Texas, Denton, Texas; 2Department of Biological Sciences, University of North Texas, Denton, Texas; and 3Department of Physiology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
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Smiles WJ, Parr EB, Coffey VG, Lacham-Kaplan O, Hawley JA, Camera DM. Protein coingestion with alcohol following strenuous exercise attenuates alcohol-induced intramyocellular apoptosis and inhibition of autophagy. Am J Physiol Endocrinol Metab 2016; 311:E836-E849. [PMID: 27677502 DOI: 10.1152/ajpendo.00303.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 09/20/2016] [Indexed: 01/16/2023]
Abstract
Alcohol ingestion decreases postexercise rates of muscle protein synthesis, but the mechanism(s) (e.g., increased protein breakdown) underlying this observation is unknown. Autophagy is an intracellular "recycling" system required for homeostatic substrate and organelle turnover; its dysregulation may provoke apoptosis and lead to muscle atrophy. We investigated the acute effects of alcohol ingestion on autophagic cell signaling responses to a bout of concurrent (combined resistance- and endurance-based) exercise. In a randomized crossover design, eight physically active males completed three experimental trials of concurrent exercise with either postexercise ingestion of alcohol and carbohydrate (12 ± 2 standard drinks; ALC-CHO), energy-matched alcohol and protein (ALC-PRO), or protein (PRO) only. Muscle biopsies were taken at rest and 2 and 8 h postexercise. Select autophagy-related gene (Atg) proteins decreased compared with rest with ALC-CHO (P < 0.05) but not ALC-PRO. There were parallel increases (P < 0.05) in p62 and PINK1 commensurate with a reduction in BNIP3 content, indicating a diminished capacity for mitochondria-specific autophagy (mitophagy) when alcohol and carbohydrate were coingested. DNA fragmentation increased in both alcohol conditions (P < 0.05); however, nuclear AIF accumulation preceded this apoptotic response with ALC-CHO only (P < 0.05). In contrast, increases in the nuclear content of p53, TFEB, and PGC-1α in ALC-PRO were accompanied by markers of mitochondrial biogenesis at the transcriptional (Tfam, SCO2, and NRF-1) and translational (COX-IV, ATPAF1, and VDAC1) level (P < 0.05). We conclude that alcohol ingestion following exercise triggers apoptosis, whereas the anabolic properties of protein coingestion may stimulate mitochondrial biogenesis to protect cellular homeostasis.
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Affiliation(s)
- William J Smiles
- Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, Victoria, Australia
| | - Evelyn B Parr
- Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, Victoria, Australia
| | - Vernon G Coffey
- Bond Institute of Health and Sport and Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland, Australia; and
| | - Orly Lacham-Kaplan
- Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, Victoria, Australia
| | - John A Hawley
- Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, Victoria, Australia
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Donny M Camera
- Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, Victoria, Australia;
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Shenkman BS, Zinovyeva OE, Belova SP, Samkhaeva ND, Shcheglova NS, Mirzoev TM, Vilchinskaya NA, Altaeva EG, Turtikova OV, Nemirovskaya TL. The response of skeletal muscle to alcohol abuse: Gender differences. Biophysics (Nagoya-shi) 2016. [DOI: 10.1134/s0006350916050262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Souza-Smith FM, Lang CH, Nagy LE, Bailey SM, Parsons LH, Murray GJ. Physiological processes underlying organ injury in alcohol abuse. Am J Physiol Endocrinol Metab 2016; 311:E605-19. [PMID: 27436613 PMCID: PMC5142006 DOI: 10.1152/ajpendo.00270.2016] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 07/11/2016] [Indexed: 02/07/2023]
Abstract
This review summarizes the American Physiological Society (APS) Presidential Symposium 1 entitled "Physiological Processes Underlying Organ Injury in Alcohol Abuse" at the 2016 Experimental Biology meeting. The symposium was organized by Dr. Patricia Molina, past president of the APS, was held on April 3 at the Convention Center in San Diego, CA, and was funded by the National Institute on Alcohol Abuse and Alcoholism. The "Physiological Processes Underlying Organ Injury in Alcohol Abuse Symposium" assembled experts and leaders in the field and served as a platform to discuss and share knowledge on the latest developments and scientific advances on the mechanisms underlying organ injury in alcohol abuse. This symposium provided unique, interdisciplinary alcohol research, including several organs, liver, muscle, adipose, and brain, affected by excessive alcohol use.
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Affiliation(s)
- Flavia M Souza-Smith
- Department of Physiology, Louisiana State University Health Science Center, New Orleans, Louisiana;
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Laura E Nagy
- Department of Pathobiology, Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio
| | - Shannon M Bailey
- Department of Pathology, University of Alabama, Birmingham, Alabama
| | | | - Gary J Murray
- National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland
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Abstract
Nutrition is one method to counter the negative impact of an exercise-induced injury. Deficiencies of energy, protein and other nutrients should be avoided. Claims for the effectiveness of many other nutrients following injuries are rampant, but the evidence is equivocal. The results of an exercise-induced injury may vary widely depending on the nature of the injury and severity. Injuries typically result in cessation, or at least a reduction, in participation in sport and decreased physical activity. Limb immobility may be necessary with some injuries, contributing to reduced activity and training. Following an injury, an inflammatory response is initiated and while excess inflammation may be harmful, given the importance of the inflammatory process for wound healing, attempting to drastically reduce inflammation may not be ideal for optimal recovery. Injuries severe enough for immobilization of a limb result in loss of muscle mass and reduced muscle strength and function. Loss of muscle results from reductions in basal muscle protein synthesis and the resistance of muscle to anabolic stimulation. Energy balance is critical. Higher protein intakes (2-2.5 g/kg/day) seem to be warranted during immobilization. At the very least, care should be taken not to reduce the absolute amount of protein intake when energy intake is reduced. There is promising, albeit preliminary, evidence for the use of omega-3 fatty acids and creatine to counter muscle loss and enhance hypertrophy, respectively. The overriding nutritional recommendation for injured exercisers should be to consume a well-balanced diet based on whole, minimally processed foods or ingredients made from whole foods. The diet composition should be carefully assessed and changes considered as the injury heals and activity patterns change.
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Affiliation(s)
- Kevin D Tipton
- Health and Exercise Sciences Research Group, University of Stirling, Cottrell Building, Stirling, FK9 4LA, Scotland, UK.
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Leucine alleviates dexamethasone-induced suppression of muscle protein synthesis via synergy involvement of mTOR and AMPK pathways. Biosci Rep 2016; 36:BSR20160096. [PMID: 27129299 PMCID: PMC5293580 DOI: 10.1042/bsr20160096] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 04/28/2016] [Indexed: 12/19/2022] Open
Abstract
Both mTOR and AMPK pathways are involved in the DEX-induced suppression of protein synthesis in muscle cells. Leucine supplementation relieves DEX-induced inhibition on protein synthesis by evoking mTOR and suppressing AMPK pathway. Glucocorticoids (GCs) are negative muscle protein regulators that contribute to the whole-body catabolic state during stress. Mammalian target of rapamycin (mTOR)-signalling pathway, which acts as a central regulator of protein metabolism, can be activated by branched-chain amino acids (BCAA). In the present study, the effect of leucine on the suppression of protein synthesis induced by GCs and the pathway involved were investigated. In vitro experiments were conducted using cultured C2C12 myoblasts to study the effect of GCs on protein synthesis, and the involvement of mTOR pathway was investigated as well. After exposure to dexamethasone (DEX, 100 μmol/l) for 24 h, protein synthesis in muscle cells was significantly suppressed (P<0.05), the phosphorylations of mTOR, ribosomal protein S6 protein kinase 1 (p70s6k1) and eukaryotic initiation factor 4E binding protein 1 (4EBP1) were significantly reduced (P<0.05). Leucine supplementation (5 mmol/l, 10 mmol/l and 15 mmol/l) for 1 h alleviated the suppression of protein synthesis induced by DEX (P<0.05) and was accompanied with the increased phosphorylation of mTOR and decreased phosphorylation of AMPK (P<0.05). Branched-chain amino transferase 2 (BCAT2) mRNA level was not influenced by DEX (P>0.05) but was increased by leucine supplementation at a dose of 5 mmol/l (P<0.05).
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Xu W, Bai K, He J, Su W, Dong L, Zhang L, Wang T. Leucine improves growth performance of intrauterine growth retardation piglets by modifying gene and protein expression related to protein synthesis. Nutrition 2016; 32:114-21. [DOI: 10.1016/j.nut.2015.07.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 05/31/2015] [Accepted: 07/07/2015] [Indexed: 01/10/2023]
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Abstract
Excessive ethanol exposure is detrimental to the brain. The developing brain is particularly vulnerable to ethanol such that prenatal ethanol exposure causes fetal alcohol spectrum disorders (FASD). Neuronal loss in the brain is the most devastating consequence and is associated with mental retardation and other behavioral deficits observed in FASD. Since alcohol consumption during pregnancy has not declined, it is imperative to elucidate the underlying mechanisms and develop effective therapeutic strategies. One cellular mechanism that acts as a protective response for the central nervous system (CNS) is autophagy. Autophagy regulates lysosomal turnover of organelles and proteins within cells, and is involved in cell differentiation, survival, metabolism, and immunity. We have recently shown that ethanol activates autophagy in the developing brain. The autophagic preconditioning alleviates ethanol-induced neuron apoptosis, whereas inhibition of autophagy potentiates ethanol-stimulated reactive oxygen species (ROS) and exacerbates ethanol-induced neuroapoptosis. The expression of genes encoding proteins required for autophagy in the CNS is developmentally regulated; their levels are much lower during an ethanol-sensitive period than during an ethanol-resistant period. Ethanol may stimulate autophagy through multiple mechanisms; these include induction of oxidative stress and endoplasmic reticulum stress, modulation of MTOR and AMPK signaling, alterations in BCL2 family proteins, and disruption of intracellular calcium (Ca2+) homeostasis. This review discusses the most recent evidence regarding the involvement of autophagy in ethanol-mediated neurotoxicity as well as the potential therapeutic approach of targeting autophagic pathways.
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Key Words
- AD, Alzheimer disease
- ALS, autophagy-lysosome system
- AMPK, adenosine 5′-monophosphate-activated protein kinase;
- ATG, autophagy-related
- CNS, central nervous system
- ER, endoplasmic reticulum
- FASD, fetal alcohol spectrum disorders
- FOXO3, forkhead box O3
- GSK3B, glycogen synthase kinase 3 β
- HD, Huntington disease, HNSCs, hippocampal neural stem cells
- LC3, microtubule-associated protein 1 light chain 3
- MTOR, mechanistic target of rapamycin (serine/threonine kinase)
- MTORC1, MTOR complex 1
- NFE2L2, nuclear factor, erythroid 2-like 2
- NOX, NADPH oxidase
- PD, Parkinson disease
- PI3K, class I phosphoinositide 3-kinase
- ROS, reactive oxygen species
- SQSTM1/p62, sequestosome 1
- TSC1/2, tuberous sclerosis 1/ 2
- UPR, unfolded protein response
- alcohol
- alcoholism
- development
- fetal alcohol spectrum disorders
- neurodegeneration
- oxidative stress
- protein degradation
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Affiliation(s)
- Jia Luo
- a Department of Pharmacology and Nutritional Sciences ; University of Kentucky College of Medicine ; Lexington , KY USA
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Pereira MG, Silva MT, da Cunha FM, Moriscot AS, Aoki MS, Miyabara EH. Leucine supplementation improves regeneration of skeletal muscles from old rats. Exp Gerontol 2015; 72:269-77. [DOI: 10.1016/j.exger.2015.10.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 10/06/2015] [Accepted: 10/15/2015] [Indexed: 12/11/2022]
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Haugvad A, Haugvad L, Hamarsland H, Paulsen G. Ethanol does not delay muscle recovery but decreases testosterone/cortisol ratio. Med Sci Sports Exerc 2015; 46:2175-83. [PMID: 24658221 DOI: 10.1249/mss.0000000000000339] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE This study investigated the effects of ethanol consumption on recovery from traditional resistance exercise in recreationally trained individuals. METHODS Nine recreationally trained volunteers (eight males and one female, 26 ± 4 yr, 81 ± 4 kg) conducted four resistance exercise sessions and consumed a low (0.6 (females) and 0.7 (males) g · kg(-1) body mass) or a high dose (1.2 or 1.4 g · kg(-1) body mass) of ethanol 1-2.5 h after exercise on two occasions. The first session was for familiarization with the tests and exercises and was performed without ethanol consumption. As a control trial, alcohol-free drinks were consumed after the exercise session. The sequence of trials, with low and high ethanol doses and alcohol-free drinks (control), was randomized. Maximal voluntary contractions (MVC) (knee extension), electrically stimulated contractions (knee extension), squat jumps, and hand grip strength were assessed 10-15 min and 12 and 24 h after the ethanol/placebo drinks. In addition to a baseline sample, blood was collected 1, 12, and 24 h after the ethanol/placebo drinks. The exercise session comprised 4 × 8 repetition maximum of squats, leg presses, and knee extensions. RESULTS MVC were reduced by 13%-15% immediately after the exercise sessions (P < 0.01). MVC, electrically stimulated force, and squat jump performance were recovered 24 h after ethanol drinks. MVC was not fully recovered at 24 h in the control trial. Compared with those in the control, cortisol increased and the free testosterone/cortisol ratio were reduced after the high ethanol dose (P < 0.01). CONCLUSIONS Neither a low nor a high dose of ethanol adversely affected recovery of muscle function after resistance exercise in recreationally strength-trained individuals. However, the increased cortisol levels and reduced testosterone/cortisol ratio after the high ethanol dose could translate into long-term negative effects.
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Affiliation(s)
- Anders Haugvad
- 1Jessenius Faculty of Medicine, Martin, SLOVAKIA; 2Norwegian Olympic Federation, Oslo, NORWAY; and 3Norwegian School of Sport Sciences, Oslo, NORWAY
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Double-blind, placebo-controlled pilot trial of L-Leucine-enriched amino-acid mixtures on body composition and physical performance in men and women aged 65-75 years. Eur J Clin Nutr 2015; 70:182-8. [PMID: 26081485 PMCID: PMC4744242 DOI: 10.1038/ejcn.2015.91] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 04/10/2015] [Accepted: 04/17/2015] [Indexed: 02/07/2023]
Abstract
Background/Objectives: Adequate protein intake is essential to retaining muscle and maintaining physical function, especially in the elderly, and L-Leucine has received attention as an essential amino acid (EAA) that enhances protein retention. The study's aim was to compare the efficacy of EAA mixtures on lean tissue mass (LTM) and functional performance (FP) in a healthy elderly population. Subjects/Methods: Thirty-six subjects (65–75 years) volunteered to receive capsules with EAAs (Groups A and B containing 20% and 40% L-Leucine, respectively) or placebo (lactose containing 0% L-Leucine, Group C) for 12 weeks. The daily amount ranged from 11 to 21 g (0.21 g/ kg/day) and was taken in two equal dosages alongside food, morning and evening. Main outcomes measured before and after intervention were LTM and FP (30-s arm-curl test; 30-s chair-stand test (30-CST); 6-min walk test (6-WT); and handgrip strength). Secondary outcomes included dietary intakes and physical activity. Results: Twenty-five subjects (11 male and 14 female) completed the study (Group A, n=8; Group B, n=8; Group C, n=9). Gains associated with medium effect sizes were noted in LTM (Group B, 1.1 ±1.1%, P=0.003) and FP (Group A in 30-CST (11.0±11.5%, P=0.02) and 6-WT (8.8±10.0%, P=0.02); Group B in 6-WT (5.8±6.6%, P=0.03) and a trend in 30-CST (13.2±16.0, P=0.06)). Significant differences between groups were not observed in secondary outcomes. Conclusions: Twice-daily supplementation of EAAs containing 20% or 40% L-Leucine improved aspects of functional status and at the higher level improved LTM. Further work to establish change in a larger sample and palatable supplemental format is now required.
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Steiner JL, Lang CH. Dysregulation of skeletal muscle protein metabolism by alcohol. Am J Physiol Endocrinol Metab 2015; 308:E699-712. [PMID: 25759394 PMCID: PMC4420901 DOI: 10.1152/ajpendo.00006.2015] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/03/2015] [Indexed: 12/12/2022]
Abstract
Alcohol abuse, either by acute intoxication or prolonged excessive consumption, leads to pathological changes in many organs and tissues including skeletal muscle. As muscle protein serves not only a contractile function but also as a metabolic reserve for amino acids, which are used to support the energy needs of other tissues, its content is tightly regulated and dynamic. This review focuses on the etiology by which alcohol perturbs skeletal muscle protein balance and thereby over time produces muscle wasting and weakness. The preponderance of data suggest that alcohol primarily impairs global protein synthesis, under basal conditions as well as in response to several anabolic stimuli including growth factors, nutrients, and muscle contraction. This inhibitory effect of alcohol is mediated, at least in part, by a reduction in mTOR kinase activity via a mechanism that remains poorly defined but likely involves altered protein-protein interactions within mTOR complex 1. Furthermore, alcohol can exacerbate the decrement in mTOR and/or muscle protein synthesis present in other catabolic states. In contrast, alcohol-induced changes in muscle protein degradation, either global or via specific modulation of the ubiquitin-proteasome or autophagy pathways, are relatively inconsistent and may be model dependent. Herein, changes produced by acute intoxication versus chronic ingestion are contrasted in relation to skeletal muscle metabolism, and limitations as well as opportunities for future research are discussed. As the proportion of more economically developed countries ages and chronic illness becomes more prevalent, a better understanding of the etiology of biomedical consequences of alcohol use disorders is warranted.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
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Steiner JL, Gordon BS, Lang CH. Moderate alcohol consumption does not impair overload-induced muscle hypertrophy and protein synthesis. Physiol Rep 2015; 3:3/3/e12333. [PMID: 25780086 PMCID: PMC4393167 DOI: 10.14814/phy2.12333] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Chronic alcohol consumption leads to muscle weakness and atrophy in part by suppressing protein synthesis and mTORC1-mediated signaling. However, it is unknown whether moderate alcohol consumption also prevents overload-induced muscle growth and related anabolic signaling. Hypertrophy of the plantaris muscle was induced by removal of a section of the gastrocnemius and soleus muscles from one leg of C57BL/6 adult male mice while the contralateral leg remained intact as the sham control. A nutritionally complete alcohol-containing liquid diet (EtOH) or isocaloric, alcohol-free liquid diet (Con) was provided for 14 days post-surgery. EtOH intake was increased progressively (day 1-5) before being maintained at ~20 g/day/kg BW. The plantaris muscle from the sham and OL leg was removed after 14 days at which time there was no difference in body weight between Con and EtOH-fed mice. OL increased muscle weight (90%) and protein synthesis (125%) in both Con and EtOH mice. The overload-induced increase in mTOR (Ser2448), 4E-BP1 (Thr37/46), S6K1 (Thr389), rpS6 (Ser240/244), and eEF2 (Thr56) were comparable in muscle from Con and EtOH mice. Modulation of signaling upstream of mTORC1 including REDD1 protein expression, Akt (Thr308), PRAS40 (Thr246), and ERK (Thr202/Tyr204) also did not differ between Con and EtOH mice. Markers of autophagy (ULK1, p62, and LC3) suggested inhibition of autophagy with overload and activation with alcohol feeding. These data show that moderate alcohol consumption does not impair muscle growth, and therefore imply that resistance exercise may be an effective therapeutic modality for alcoholic-related muscle disease.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Bradley S Gordon
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, Pennsylvania
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Steiner JL, Lang CH. Alcohol intoxication following muscle contraction in mice decreases muscle protein synthesis but not mTOR signal transduction. Alcohol Clin Exp Res 2015; 39:1-10. [PMID: 25623400 PMCID: PMC4308817 DOI: 10.1111/acer.12600] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/13/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Alcohol (ethanol [EtOH]) intoxication antagonizes stimulation of muscle protein synthesis and mammalian target of rapamycin (mTOR) signaling. However, whether the anabolic response can be reversed when alcohol is consumed after the stimulus is unknown. METHODS A single bout of electrically stimulated muscle contractions (10 sets of 6 contractions) was induced in fasted male C57BL/6 mice 2 hours prior to alcohol intoxication. EtOH was injected intraperitoneally (3 g/kg), and the gastrocnemius/plantaris muscle complex was collected 2 hours later from the stimulated and contralateral unstimulated control leg. RESULTS Muscle contraction increased protein synthesis 28% in control mice, while EtOH abolished this stimulation-induced increase. Further, EtOH suppressed the rate of synthesis ~75% compared to control muscle irrespective of stimulation. This decrease was associated with impaired protein elongation as EtOH increased the phosphorylation of eEF2 Thr(56) . In contrast, stimulation-induced increases in mTOR protein complex-1 (mTORC1) (S6K1 Thr(421) /Ser(424) , S6K1 Thr(389) , rpS6 Ser(240/244) , and 4E-BP1 Thr(37/46) ) and mitogen-activated protein kinase (MAPK) (JNK Thr(183) /Tyr(185) , p38 Thr(180) /Tyr(182) , and rpS6S(235/236) ) signaling were not reversed by acute EtOH. CONCLUSIONS These data suggest that EtOH-induced decreases in protein synthesis in fasted mice may be independent of mTORC1 and MAPK signaling following muscle contraction and instead due to the antagonistic actions of EtOH on mRNA translation elongation. Therefore, EtOH suppresses the contraction-induced increase in protein synthesis, and over time has the potential to prevent skeletal muscle hypertrophy induced by repeated muscle contraction.
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Affiliation(s)
- Jennifer L. Steiner
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
| | - Charles H. Lang
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033
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Pereira MG, Silva MT, Carlassara EOC, Gonçalves DA, Abrahamsohn PA, Kettelhut IC, Moriscot AS, Aoki MS, Miyabara EH. Leucine supplementation accelerates connective tissue repair of injured tibialis anterior muscle. Nutrients 2014; 6:3981-4001. [PMID: 25268835 PMCID: PMC4210903 DOI: 10.3390/nu6103981] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/22/2014] [Accepted: 09/05/2014] [Indexed: 11/30/2022] Open
Abstract
This study investigated the effect of leucine supplementation on the skeletal muscle regenerative process, focusing on the remodeling of connective tissue of the fast twitch muscle tibialis anterior (TA). Young male Wistar rats were supplemented with leucine (1.35 g/kg per day); then, TA muscles from the left hind limb were cryolesioned and examined after 10 days. Although leucine supplementation induced increased protein synthesis, it was not sufficient to promote an increase in the cross-sectional area (CSA) of regenerating myofibers (p > 0.05) from TA muscles. However, leucine supplementation reduced the amount of collagen and the activation of phosphorylated transforming growth factor-β receptor type I (TβR-I) and Smad2/3 in regenerating muscles (p < 0.05). Leucine also reduced neonatal myosin heavy chain (MyHC-n) (p < 0.05), increased adult MyHC-II expression (p < 0.05) and prevented the decrease in maximum tetanic strength in regenerating TA muscles (p < 0.05). Our results suggest that leucine supplementation accelerates connective tissue repair and consequent function of regenerating TA through the attenuation of TβR-I and Smad2/3 activation. Therefore, future studies are warranted to investigate leucine supplementation as a nutritional strategy to prevent or attenuate muscle fibrosis in patients with several muscle diseases.
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Affiliation(s)
- Marcelo G Pereira
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil.
| | - Meiricris T Silva
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil.
| | - Eduardo O C Carlassara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil.
| | - Dawit A Gonçalves
- Department of Physiology and Biochemistry/Immunology, School of Medicine, University of Sao Paulo, Bandeirantes Av. 3900, Ribeirao Preto, SP 14049-900, Brazil.
| | - Paulo A Abrahamsohn
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 1524, Sao Paulo, SP 05508-000, Brazil.
| | - Isis C Kettelhut
- Department of Physiology and Biochemistry/Immunology, School of Medicine, University of Sao Paulo, Bandeirantes Av. 3900, Ribeirao Preto, SP 14049-900, Brazil.
| | - Anselmo S Moriscot
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil.
| | - Marcelo S Aoki
- School of Arts, Sciences and Humanities, University of Sao Paulo, Arlindo Bettio Av. 1000, Sao Paulo, SP 03828-000, Brazil.
| | - Elen H Miyabara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Prof. Lineu Prestes Av. 2415, Sao Paulo, SP 05508-000, Brazil.
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Steiner JL, Lang CH. Alcohol impairs skeletal muscle protein synthesis and mTOR signaling in a time-dependent manner following electrically stimulated muscle contraction. J Appl Physiol (1985) 2014; 117:1170-9. [PMID: 25257868 DOI: 10.1152/japplphysiol.00180.2014] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Alcohol (EtOH) decreases protein synthesis and mammalian target of rapamycin (mTOR)-mediated signaling and blunts the anabolic response to growth factors in skeletal muscle. The purpose of the current investigation was to determine whether acute EtOH intoxication antagonizes the contraction-induced increase in protein synthesis and mTOR signaling in skeletal muscle. Fasted male mice were injected intraperitoneally with 3 g/kg EtOH or saline (control), and the right hindlimb was electrically stimulated (10 sets of 6 contractions). The gastrocnemius muscle complex was collected 30 min, 4 h, or 12 h after stimulation. EtOH decreased in vivo basal protein synthesis (PS) in the nonstimulated muscle compared with time-matched Controls at 30 min, 4 h, and 12 h. In Control, but not EtOH, PS was decreased 15% after 30 min. In contrast, PS was increased in Control 4 h poststimulation but remained unchanged in EtOH. Last, stimulation increased PS 10% in Control and EtOH at 12 h, even though the absolute rate remained reduced by EtOH. The stimulation-induced increase in the phosphorylation of S6K1 Thr(421)/Ser(424) (20-52%), S6K1 Thr(389) (45-57%), and its substrate rpS6 Ser(240/244) (37-72%) was blunted by EtOH at 30 min, 4 h, and 12 h. Phosphorylation of 4E-BP1 Ser(65) was also attenuated by EtOH (61%) at 4 h. Conversely, phosphorylation of extracellular signal-regulated kinase Thr(202)/Tyr(204) was increased by stimulation in Control and EtOH mice at 30 min but only in Control at 4 h. Our data indicate that acute EtOH intoxication suppresses muscle protein synthesis for at least 12 h and greatly impairs contraction-induced changes in synthesis and mTOR signaling.
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Affiliation(s)
- Jennifer L Steiner
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
| | - Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State College of Medicine, Hershey, Pennsylvania
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Manring H, Abreu E, Brotto L, Weisleder N, Brotto M. Novel excitation-contraction coupling related genes reveal aspects of muscle weakness beyond atrophy-new hopes for treatment of musculoskeletal diseases. Front Physiol 2014; 5:37. [PMID: 24600395 PMCID: PMC3927072 DOI: 10.3389/fphys.2014.00037] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/18/2014] [Indexed: 12/16/2022] Open
Abstract
Research over the last decade strengthened the understanding that skeletal muscles are not only the major tissue in the body from a volume point of view but also function as a master regulator contributing to optimal organismal health. These new contributions to the available body of knowledge triggered great interest in the roles of skeletal muscle beyond contraction. The World Health Organization, through its Global Burden of Disease (GBD) report, recently raised further awareness about the key importance of skeletal muscles as the GDB reported musculoskeletal (MSK) diseases have become the second greatest cause of disability, with more than 1.7 billion people in the globe affected by a diversity of MSK conditions. Besides their role in MSK disorders, skeletal muscles are also seen as principal metabolic organs with essential contributions to metabolic disorders, especially those linked to physical inactivity. In this review, we have focused on the unique function of new genes/proteins (i.e., MTMR14, MG29, sarcalumenin, KLF15) that during the last few years have helped provide novel insights about muscle function in health and disease, muscle fatigue, muscle metabolism, and muscle aging. Next, we provide an in depth discussion of how these genes/proteins converge into a common function of acting as regulators of intracellular calcium homeostasis. A clear link between dysfunctional calcium homeostasis is established and the special role of store-operated calcium entry is analyzed. The new knowledge that has been generated by the understanding of the roles of previously unknown modulatory genes of the skeletal muscle excitation-contraction coupling (ECC) process brings exciting new possibilities for treatment of MSK diseases, muscle regeneration, and skeletal muscle tissue engineering. The next decade of skeletal muscle and MSK research is bound to bring to fruition applied knowledge that will hopefully offset the current heavy and sad burden of MSK diseases on the planet.
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Affiliation(s)
- Heather Manring
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Eduardo Abreu
- Muscle Biology Research Group, School of Nursing and Health Studies, University of Missouri-Kansas City Kansas City, MO, USA
| | - Leticia Brotto
- Muscle Biology Research Group, School of Nursing and Health Studies, University of Missouri-Kansas City Kansas City, MO, USA
| | - Noah Weisleder
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center Columbus, OH, USA
| | - Marco Brotto
- Muscle Biology Research Group, School of Nursing and Health Studies, University of Missouri-Kansas City Kansas City, MO, USA ; Basic Medical Sciences Pharmacology, School of Medicine, University of Missouri-Kansas City Kansas City, MO, USA ; Basic Medical Sciences Pharmacology, School of Pharmacy, University of Missouri-Kansas City Kansas City, MO, USA
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44
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Parr EB, Camera DM, Areta JL, Burke LM, Phillips SM, Hawley JA, Coffey VG. Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis following a single bout of concurrent training. PLoS One 2014; 9:e88384. [PMID: 24533082 PMCID: PMC3922864 DOI: 10.1371/journal.pone.0088384] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Accepted: 01/06/2014] [Indexed: 01/11/2023] Open
Abstract
Introduction The culture in many team sports involves consumption of large amounts of alcohol after training/competition. The effect of such a practice on recovery processes underlying protein turnover in human skeletal muscle are unknown. We determined the effect of alcohol intake on rates of myofibrillar protein synthesis (MPS) following strenuous exercise with carbohydrate (CHO) or protein ingestion. Methods In a randomized cross-over design, 8 physically active males completed three experimental trials comprising resistance exercise (8×5 reps leg extension, 80% 1 repetition maximum) followed by continuous (30 min, 63% peak power output (PPO)) and high intensity interval (10×30 s, 110% PPO) cycling. Immediately, and 4 h post-exercise, subjects consumed either 500 mL of whey protein (25 g; PRO), alcohol (1.5 g·kg body mass−1, 12±2 standard drinks) co-ingested with protein (ALC-PRO), or an energy-matched quantity of carbohydrate also with alcohol (25 g maltodextrin; ALC-CHO). Subjects also consumed a CHO meal (1.5 g CHO·kg body mass−1) 2 h post-exercise. Muscle biopsies were taken at rest, 2 and 8 h post-exercise. Results Blood alcohol concentration was elevated above baseline with ALC-CHO and ALC-PRO throughout recovery (P<0.05). Phosphorylation of mTORSer2448 2 h after exercise was higher with PRO compared to ALC-PRO and ALC-CHO (P<0.05), while p70S6K phosphorylation was higher 2 h post-exercise with ALC-PRO and PRO compared to ALC-CHO (P<0.05). Rates of MPS increased above rest for all conditions (∼29–109%, P<0.05). However, compared to PRO, there was a hierarchical reduction in MPS with ALC-PRO (24%, P<0.05) and with ALC-CHO (37%, P<0.05). Conclusion We provide novel data demonstrating that alcohol consumption reduces rates of MPS following a bout of concurrent exercise, even when co-ingested with protein. We conclude that alcohol ingestion suppresses the anabolic response in skeletal muscle and may therefore impair recovery and adaptation to training and/or subsequent performance.
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Affiliation(s)
- Evelyn B. Parr
- Exercise and Nutrition Research Group, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Donny M. Camera
- Exercise and Nutrition Research Group, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - José L. Areta
- Exercise and Nutrition Research Group, School of Medical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Louise M. Burke
- Department of Sports Nutrition, Australian Institute of Sport, Canberra, ACT, Australia
| | - Stuart M. Phillips
- Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - John A. Hawley
- Exercise and Nutrition Research Group, School of Exercise Science, Australian Catholic University, Fitzroy, Victoria, Australia
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
- * E-mail:
| | - Vernon G. Coffey
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia
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Pereira MG, Baptista IL, Carlassara EOC, Moriscot AS, Aoki MS, Miyabara EH. Leucine supplementation improves skeletal muscle regeneration after cryolesion in rats. PLoS One 2014; 9:e85283. [PMID: 24416379 PMCID: PMC3885703 DOI: 10.1371/journal.pone.0085283] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 11/25/2013] [Indexed: 12/31/2022] Open
Abstract
This study was undertaken in order to provide further insight into the role of leucine supplementation in the skeletal muscle regeneration process, focusing on myofiber size and strength recovery. Young (2-month-old) rats were subjected or not to leucine supplementation (1.35 g/kg per day) started 3 days prior to cryolesion. Then, soleus muscles were cryolesioned and continued receiving leucine supplementation until 1, 3 and 10 days later. Soleus muscles from leucine-supplemented animals displayed an increase in myofiber size and a reduction in collagen type III expression on post-cryolesion day 10. Leucine was also effective in reducing FOXO3a activation and ubiquitinated protein accumulation in muscles at post-cryolesion days 3 and 10. In addition, leucine supplementation minimized the cryolesion-induced decrease in tetanic strength and increase in fatigue in regenerating muscles at post-cryolesion day 10. These beneficial effects of leucine were not accompanied by activation of any elements of the phosphoinositide 3-kinase/Akt/mechanistic target of rapamycin signalling pathway in the regenerating muscles. Our results show that leucine improves myofiber size gain and strength recovery in regenerating soleus muscles through attenuation of protein ubiquitination. In addition, leucine might have therapeutic effects for muscle recovery following injury and in some muscle diseases.
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Affiliation(s)
- Marcelo G. Pereira
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Igor L. Baptista
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Eduardo O. C. Carlassara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Anselmo S. Moriscot
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Marcelo S. Aoki
- School of Arts, Sciences and Humanities, University of Sao Paulo, Sao Paulo, Brazil
| | - Elen H. Miyabara
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
- * E-mail:
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Molina PE, Bagby GJ, Nelson S. Biomedical consequences of alcohol use disorders in the HIV-infected host. Curr HIV Res 2014; 12:265-75. [PMID: 25053365 PMCID: PMC4222574 DOI: 10.2174/1570162x12666140721121849] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 04/08/2014] [Accepted: 04/08/2014] [Indexed: 02/06/2023]
Abstract
Alcohol abuse is the most common and costly form of drug abuse in the United States. It is well known that alcohol abuse contributes to risky behaviors associated with greater incidence of human immunodeficiency virus (HIV) infections. As HIV has become a more chronic disease since the introduction of antiretroviral therapy, it is expected that alcohol use disorders will have an adverse effect on the health of HIV-infected patients. The biomedical consequences of acute and chronic alcohol abuse are multisystemic. Based on what is currently known of the comorbid and pathophysiological conditions resulting from HIV infection in people with alcohol use disorders, chronic alcohol abuse appears to alter the virus infectivity, the immune response of the host, and the progression of disease and tissue injury, with specific impact on disease progression. The combined insult of alcohol abuse and HIV affects organ systems, including the central nervous system, the immune system, the liver, heart, and lungs, and the musculoskeletal system. Here we outline the major pathological consequences of alcohol abuse in the HIV-infected individual, emphasizing its impact on immunomodulation, erosion of lean body mass associated with AIDS wasting, and lipodystrophy. We conclude that interventions focused on reducing or avoiding alcohol abuse are likely to be important in decreasing morbidity and improving outcomes in people living with HIV/AIDS.
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Affiliation(s)
| | | | - Steve Nelson
- LSUHSC Physiology, 1901 Perdido St., New Orleans, LA 70112, USA.
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Gritsyna YV, Salmov NN, Vikhlyantsev IM, Ulanova AD, Sharapov MG, Teplova VV, Podlubnaya ZA. Changes in gene expression and titin (connectin) content in striated muscles of chronically alcoholized rats. Mol Biol 2013. [DOI: 10.1134/s0026893313060058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Lang CH, Korzick DH. Chronic alcohol consumption disrupts myocardial protein balance and function in aged, but not adult, female F344 rats. Am J Physiol Regul Integr Comp Physiol 2013; 306:R23-33. [PMID: 24226028 DOI: 10.1152/ajpregu.00414.2013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The purpose of this study was to assess whether the deleterious effect of chronic alcohol consumption differs in adult and aged female rats. To address this aim, adult (4 mo) and aged (18 mo) F344 rats were fed a nutritionally complete liquid diet containing alcohol (36% total calories) or an isocaloric isonitrogenous control diet for 20 wk. Cardiac structure and function, assessed by echocardiography, as well as myocardial protein synthesis and proteolysis did not differ in either alcohol- versus control-fed adult rats or in adult versus aged control-fed rats. In contrast, cardiac function was impaired in alcohol-fed aged rats compared with age-matched control rats. Additionally, alcohol feeding decreased cardiac protein synthesis that was associated with decreased phosphorylation of 4E-BP1 and S6K1. This reduction in mammalian target of rapamycin (mTOR) kinase activity was associated with reduced eIF3f and binding of both Raptor and eIF4G to eIF3. Proteasome activity was increased in alcohol-fed aged rats with a coordinate elevation in the E3 ligases atrogin-1 and muscle RING-finger protein-1 (MuRF1). These changes were associated with increased regulated in development and DNA damage response 1 (REDD1) and phosphorylation of AMP-activated protein kinase (AMPK) but no increase in AKT or forkhead transcription factor (FOXO)3 phosphorylation. Finally, markers of autophagy (e.g., LC3B, Atg7, Atg12) and TNF-α were increased to a greater extent in alcohol-fed aged rats. These data demonstrate that aged female rats exhibit an enhanced sensitivity to alcohol compared with adult animals. Our data are consistent with a model whereby alcohol increases proteolysis via FOXO-independent increase in atrogin-1, which degrades eIF3f and therefore impairs formation of a functional preinitiation complex and protein synthesis.
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Dekeyser GJ, Clary CR, Otis JS. Chronic alcohol ingestion delays skeletal muscle regeneration following injury. Regen Med Res 2013; 1:2. [PMID: 25984321 PMCID: PMC4376340 DOI: 10.1186/2050-490x-1-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 12/21/2012] [Indexed: 12/17/2022] Open
Abstract
Background Chronic alcohol ingestion may cause severe biochemical and pathophysiological derangements to skeletal muscle. Unfortunately, these alcohol-induced events may also prime skeletal muscle for worsened, delayed, or possibly incomplete repair following acute injury. As alcoholics may be at increased risk for skeletal muscle injury, our goals were to identify the effects of chronic alcohol ingestion on components of skeletal muscle regeneration. To accomplish this, age- and gender-matched C57Bl/6 mice were provided normal drinking water or water that contained 20% alcohol (v/v) for 18–20 wk. Subgroups of mice were injected with a 1.2% barium chloride (BaCl2) solution into the tibialis anterior (TA) muscle to initiate degeneration and regeneration processes. Body weights and voluntary wheel running distances were recorded during the course of recovery. Muscles were harvested at 2, 7 or 14 days post-injection and assessed for markers of inflammation and oxidant stress, fiber cross-sectional areas, levels of growth and fibrotic factors, and fibrosis. Results Body weights of injured, alcohol-fed mice were reduced during the first week of recovery. These mice also ran significantly shorter distances over the two weeks following injury compared to uninjured, alcoholics. Injured TA muscles from alcohol-fed mice had increased TNFα and IL6 gene levels compared to controls 2 days after injury. Total protein oxidant stress and alterations to glutathione homeostasis were also evident at 7 and 14 days after injury. Ciliary neurotrophic factor (CNTF) induction was delayed in injured muscles from alcohol-fed mice which may explain, in part, why fiber cross-sectional area failed to normalize 14 days following injury. Gene levels of TGFβ1 were induced early following injury before normalizing in muscle from alcohol-fed mice compared to controls. However, TGFβ1 protein content was consistently elevated in injured muscle regardless of diet. Fibrosis was increased in injured, muscle from alcohol-fed mice at 7 and 14 days of recovery compared to injured controls. Conclusions Chronic alcohol ingestion appears to delay the normal regenerative response following significant skeletal muscle injury. This is evidenced by reduced cross-sectional areas of regenerated fibers, increased fibrosis, and altered temporal expression of well-described growth and fibrotic factors.
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Affiliation(s)
- Graham J Dekeyser
- Department of Kinesiology and Health, Georgia State University, Atlanta, GA 30322 USA
| | | | - Jeffrey S Otis
- Department of Kinesiology and Health, Georgia State University, Atlanta, GA 30322 USA
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50
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Lang CH, Pruznak A, Navaratnarajah M, Rankine KA, Deiter G, Magne H, Offord EA, Breuillé D. Chronic α-hydroxyisocaproic acid treatment improves muscle recovery after immobilization-induced atrophy. Am J Physiol Endocrinol Metab 2013; 305:E416-28. [PMID: 23757407 DOI: 10.1152/ajpendo.00618.2012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Muscle disuse atrophy is observed routinely in patients recovering from traumatic injury and can be either generalized resulting from extended bed rest or localized resulting from single-limb immobilization. The present study addressed the hypothesis that a diet containing 5% α-hydroxyisocaproic acid (α-HICA), a leucine (Leu) metabolite, will slow the loss and/or improve recovery of muscle mass in response to disuse. Adult 14-wk-old male Wistar rats were provided a control diet or an isonitrogenous isocaloric diet containing either 5% α-HICA or Leu. Disuse atrophy was produced by unilateral hindlimb immobilization ("casting") for 7 days and the contralateral muscle used as control. Rats were also casted for 7 days and permitted to recover for 7 or 14 days. Casting decreased gastrocnemius mass, which was associated with both a reduction in protein synthesis and S6K1 phosphorylation as well as enhanced proteasome activity and increased atrogin-1 and MuRF1 mRNA. Although neither α-HICA nor Leu prevented the casting-induced muscle atrophy, the decreased muscle protein synthesis was not observed in α-HICA-treated rats. Neither α-HICA nor Leu altered the increased proteasome activity and atrogene expression observed with immobilization. After 14 days of recovery, muscle mass had returned to control values only in the rats fed α-HICA, and this was associated with a sustained increase in protein synthesis and phosphorylation of S6K1 and 4E-BP1 of previously immobilized muscle. Proteasome activity and atrogene mRNA content were at control levels after 14 days and not affected by either treatment. These data suggest that whereas α-HICA does not slow the loss of muscle produced by disuse, it does speed recovery at least in part by maintaining an increased rate of protein synthesis.
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Affiliation(s)
- Charles H Lang
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA.
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