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Borowik AK, Lawrence MM, Peelor FF, Piekarz KM, Crosswhite A, Richardson A, Miller BF, Van Remmen H, Brown JL. Senolytic treatment does not mitigate oxidative stress-induced muscle atrophy but improves muscle force generation in CuZn superoxide dismutase knockout mice. GeroScience 2024; 46:3219-3233. [PMID: 38233728 PMCID: PMC11009189 DOI: 10.1007/s11357-024-01070-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 01/05/2024] [Indexed: 01/19/2024] Open
Abstract
Oxidative stress is associated with tissue dysfunctions that can lead to reduced health. Prior work has shown that oxidative stress contributes to both muscle atrophy and cellular senescence, which is a hallmark of aging that may drive in muscle atrophy and muscle contractile dysfunction. The purpose of the study was to test the hypothesis that cellular senescence contributes to muscle atrophy or weakness. To increase potential senescence in skeletal muscle, we used a model of oxidative stress-induced muscle frailty, the CuZn superoxide dismutase knockout (Sod1KO) mouse. We treated 6-month-old wildtype (WT) and Sod1KO mice with either vehicle or a senolytic treatment of combined dasatinib (5 mg/kg) + quercetin (50 mg/kg) (D + Q) for 3 consecutive days every 15 days. We continued treatment for 7 months and sacrificed the mice at 13 months of age. Treatment with D + Q did not preserve muscle mass, reduce NMJ fragmentation, or alter muscle protein synthesis in Sod1KO mice when compared to the vehicle-treated group. However, we observed an improvement in muscle-specific force generation in Sod1KO mice treated with D + Q when compared to Sod1KO-vehicle mice. Overall, these data suggest that reducing cellular senescence via D + Q is not sufficient to mitigate loss of muscle mass in a mouse model of oxidative stress-induced muscle frailty but may mitigate some aspects of oxidative stress-induced muscle dysfunction.
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Affiliation(s)
- Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Marcus M Lawrence
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
- Department of Kinesiology and Outdoor Recreation, Southern Utah University, Cedar City, Utah, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Katarzyna M Piekarz
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
- Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Abby Crosswhite
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Arlan Richardson
- Oklahoma City VA Medical Center, Oklahoma City, OK, 73104, USA
- Department of Biochemistry & Molecular Biology, Oklahoma University Health Science Center, Oklahoma City, OK, 73104, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
- Oklahoma City VA Medical Center, Oklahoma City, OK, 73104, USA
| | - Holly Van Remmen
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
- Oklahoma City VA Medical Center, Oklahoma City, OK, 73104, USA
| | - Jacob L Brown
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA.
- Oklahoma City VA Medical Center, Oklahoma City, OK, 73104, USA.
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Bubak MP, Davidyan A, O'Reilly CL, Mondal SA, Keast J, Doidge SM, Borowik AK, Taylor ME, Volovičeva E, Kinter MT, Britton SL, Koch LG, Stout MB, Lewis TL, Miller BF. Metformin treatment results in distinctive skeletal muscle mitochondrial remodeling in rats with different intrinsic aerobic capacities. bioRxiv 2024:2024.03.01.582957. [PMID: 38496648 PMCID: PMC10942369 DOI: 10.1101/2024.03.01.582957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
The rationale for the use of metformin as a treatment to slow aging was largely based on data collected from metabolically unhealthy individuals. For healthspan extension metformin will also be used in periods of good health. To understand potential context specificity of metformin treatment on skeletal muscle, we used a rat model (HCR/LCR) with a divide in intrinsic aerobic capacity. Outcomes of metformin treatment differed based on baseline intrinsic mitochondrial function, oxidative capacity of the muscle (gastroc vs soleus), and the mitochondrial population (IMF vs SS). Metformin caused lower ADP-stimulated respiration in LCRs, with less of a change in HCRs. However, a washout of metformin resulted in an unexpected doubling of respiratory capacity in HCRs. These improvements in respiratory capacity were accompanied by mitochondrial remodeling that included increases in protein synthesis and changes in morphology. Our findings raise questions about whether the positive findings of metformin treatment are broadly applicable.
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Bubak MP, Mann SN, Borowik AK, Pranay A, Batushansky A, Vieira de Sousa Neto I, Mondal SA, Doidge SM, Davidyan A, Szczygiel MM, Peelor FF, Rigsby S, Broomfield ME, Lacy CI, Rice HC, Stout MB, Miller BF. 17α-Estradiol alleviates high-fat diet-induced inflammatory and metabolic dysfunction in skeletal muscle of male and female mice. Am J Physiol Endocrinol Metab 2024; 326:E226-E244. [PMID: 38197793 DOI: 10.1152/ajpendo.00215.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 12/14/2023] [Accepted: 12/22/2023] [Indexed: 01/11/2024]
Abstract
17α-estradiol (17α-E2) is a naturally occurring nonfeminizing diastereomer of 17β-estradiol that has life span-extending effects in rodent models. To date, studies of the systemic and tissue-specific benefits of 17α-E2 have largely focused on the liver, brain, and white adipose tissue with far less focus on skeletal muscle. Skeletal muscle has an important role in metabolic and age-related disease. Therefore, this study aimed to determine whether 17α-E2 treatment has positive, tissue-specific effects on skeletal muscle during a high-fat feeding. We hypothesized that male, but not female, mice, would benefit from 17α-E2 treatment during a high-fat diet (HFD) with changes in the mitochondrial proteome to support lipid oxidation and subsequent reductions in diacylglycerol (DAG) and ceramide content. To test this hypothesis, we used a multiomics approach to determine changes in lipotoxic lipid intermediates, metabolites, and proteins related to metabolic homeostasis. Unexpectedly, we found that 17α-E2 had marked, but different, beneficial effects within each sex. In male mice, we show that 17α-E2 alleviates HFD-induced metabolic detriments of skeletal muscle by reducing the accumulation of diacylglycerol (DAG), and inflammatory cytokine levels, and altered the abundance of most of the proteins related to lipolysis and β-oxidation. Similar to male mice, 17α-E2 treatment reduced fat mass while protecting muscle mass in female mice but had little muscle inflammatory cytokine levels. Although female mice were resistant to HFD-induced changes in DAGs, 17α-E2 treatment induced the upregulation of six DAG species. In female mice, 17α-E2 treatment changed the relative abundance of proteins involved in lipolysis, β-oxidation, as well as structural and contractile proteins but to a smaller extent than male mice. These data demonstrate the metabolic benefits of 17α-E2 in skeletal muscle of male and female mice and contribute to the growing literature of the use of 17α-E2 for multi tissue health span benefits.NEW & NOTEWORTHY Using a multiomics approach, we show that 17α-E2 alleviates HFD-induced metabolic detriments in skeletal muscle by altering bioactive lipid intermediates, inflammatory cytokines, and the abundance of proteins related to lipolysis and muscle contraction. The positive effects of 17α-E2 in skeletal muscle occur in both sexes but differ in their outcome.
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Affiliation(s)
- Matthew P Bubak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Shivani N Mann
- Department of Neuroscience, University of Arizona, Tucson, Arizona, United States
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Albert Batushansky
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheba, Israel
| | - Ivo Vieira de Sousa Neto
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Samim A Mondal
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Stephen M Doidge
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Arik Davidyan
- Department of Biological Sciences, California State University, Sacramento, California, United States
| | - Marcelina M Szczygiel
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Sandra Rigsby
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Matle E Broomfield
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
| | - Charles I Lacy
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Geroscience and Healthy Brain Aging, Oklahoma City, Oklahoma, United States
| | - Heather C Rice
- Department of Biochemistry and Molecular Biology, Oklahoma Center for Geroscience and Healthy Brain Aging, Oklahoma City, Oklahoma, United States
| | - Michael B Stout
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Oklahoma City Veterans Affairs Medical Center, Oklahoma City, Oklahoma, United States
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States
- Oklahoma City Veterans Affairs Medical Center, Oklahoma City, Oklahoma, United States
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Fuqua JD, Lawrence MM, Hettinger ZR, Borowik AK, Brecheen PL, Szczygiel MM, Abbott CB, Peelor FF, Confides AL, Kinter M, Bodine SC, Dupont‐Versteegden EE, Miller BF. Impaired proteostatic mechanisms other than decreased protein synthesis limit old skeletal muscle recovery after disuse atrophy. J Cachexia Sarcopenia Muscle 2023; 14:2076-2089. [PMID: 37448295 PMCID: PMC10570113 DOI: 10.1002/jcsm.13285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 04/10/2023] [Accepted: 05/22/2023] [Indexed: 07/15/2023] Open
Abstract
BACKGROUND Skeletal muscle mass and strength diminish during periods of disuse but recover upon return to weight bearing in healthy adults but are incomplete in old muscle. Efforts to improve muscle recovery in older individuals commonly aim at increasing myofibrillar protein synthesis via mammalian target of rapamycin (mTOR) stimulation despite evidence demonstrating that old muscle has chronically elevated levels of mammalian target of rapamycin complex 1 (mTORC1) activity. We hypothesized that protein synthesis is higher in old muscle than adult muscle, which contributes to a proteostatic stress that impairs recovery. METHODS We unloaded hindlimbs of adult (10-month) and old (28-month) F344BN rats for 14 days to induce atrophy, followed by reloading up to 60 days with deuterium oxide (D2 O) labelling to study muscle regrowth and proteostasis. RESULTS We found that old muscle has limited recovery of muscle mass during reloading despite having higher translational capacity and myofibrillar protein synthesis (0.029 k/day ± 0.002 vs. 0.039 k/day ± 0.002, P < 0.0001) than adult muscle. We showed that collagen protein synthesis was not different (0.005 k (1/day) ± 0.0005 vs. 0.004 k (1/day) ± 0.0005, P = 0.15) in old compared to adult, but old muscle had higher collagen concentration (4.5 μg/mg ± 1.2 vs. 9.8 μg/mg ± 0.96, P < 0.01), implying that collagen breakdown was slower in old muscle than adult muscle. This finding was supported by old muscle having more insoluble collagen (4.0 ± 1.1 vs. 9.2 ± 0.9, P < 0.01) and an accumulation of advanced glycation end products (1.0 ± 0.06 vs. 1.5 ± 0.08, P < 0.001) than adult muscle during reloading. Limited recovery of muscle mass during reloading is in part due to higher protein degradation (0.017 1/t ± 0.002 vs. 0.028 1/t ± 0.004, P < 0.05) and/or compromised proteostasis as evidenced by accumulation of ubiquitinated insoluble proteins (1.02 ± 0.06 vs. 1.22 ± 0.06, P < 0.05). Last, we showed that synthesis of individual proteins related to protein folding/refolding, protein degradation and neural-related biological processes was higher in old muscle during reloading than adult muscle. CONCLUSIONS Our data suggest that the failure of old muscle to recover after disuse is not due to limitations in the ability to synthesize myofibrillar proteins but because of other impaired proteostatic mechanisms (e.g., protein folding and degradation). These data provide novel information on individual proteins that accumulate in protein aggregates after disuse and certain biological processes such as protein folding and degradation that likely play a role in impaired recovery. Therefore, interventions to enhance regrowth of old muscle after disuse should be directed towards the identified impaired proteostatic mechanisms and not aimed at increasing protein synthesis.
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Affiliation(s)
- Jordan D. Fuqua
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Marcus M. Lawrence
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
- Department of Kinesiology and Outdoor RecreationSouthern Utah UniversityCedar CityUTUSA
| | - Zachary R. Hettinger
- Department of Physical Therapy, College of Health SciencesUniversity of KentuckyLexingtonKYUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKYUSA
| | - Agnieszka K. Borowik
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Parker L. Brecheen
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Marcelina M. Szczygiel
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Claire B. Abbott
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Frederick F. Peelor
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Amy L. Confides
- Department of Physical Therapy, College of Health SciencesUniversity of KentuckyLexingtonKYUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKYUSA
| | - Michael Kinter
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
| | - Sue C. Bodine
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
- Department of Internal MedicineUniversity of IowaIowa CityIAUSA
- Fraternal Order of Eagles Diabetes Research CenterUniversity of IowaIowa CityIAUSA
- Iowa City Veterans Affairs Medical CenterIowa CityIAUSA
| | - Esther E. Dupont‐Versteegden
- Department of Physical Therapy, College of Health SciencesUniversity of KentuckyLexingtonKYUSA
- Center for Muscle BiologyUniversity of KentuckyLexingtonKYUSA
| | - Benjamin F. Miller
- Aging & Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOKUSA
- Oklahoma City Veterans Affairs Medical CenterOklahoma CityOKUSA
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5
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Batterson PM, McGowan EM, Borowik AK, Kinter MT, Miller BF, Newsom SA, Robinson MM. High-fat diet increases electron transfer flavoprotein synthesis and lipid respiration in skeletal muscle during exercise training in female mice. Physiol Rep 2023; 11:e15840. [PMID: 37857571 PMCID: PMC10587055 DOI: 10.14814/phy2.15840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/26/2023] [Accepted: 09/26/2023] [Indexed: 10/21/2023] Open
Abstract
High-fat diet (HFD) and exercise remodel skeletal muscle mitochondria. The electron transfer flavoproteins (ETF) transfer reducing equivalents from β-oxidation into the electron transfer system. Exercise may stimulate the synthesis of ETF proteins to increase lipid respiration. We determined mitochondrial remodeling for lipid respiration through ETF in the context of higher mitochondrial abundance/capacity seen in female mice. We hypothesized HFD would be a greater stimulus than exercise to remodel ETF and lipid pathways through increased protein synthesis alongside increased lipid respiration. Female C57BL/6J mice (n = 15 per group) consumed HFD or low-fat diet (LFD) for 4 weeks then remained sedentary (SED) or completed 8 weeks of treadmill training (EX). We determined mitochondrial lipid respiration, RNA abundance, individual protein synthesis, and abundance for ETFα, ETFβ, and ETF dehydrogenase (ETFDH). HFD increased absolute and relative lipid respiration (p = 0.018 and p = 0.034) and RNA abundance for ETFα (p = 0.026), ETFβ (p = 0.003), and ETFDH (p = 0.0003). HFD increased synthesis for ETFα and ETFDH (p = 0.0007 and p = 0.002). EX increased synthesis of ETFβ and ETFDH (p = 0.008 and p = 0.006). Higher synthesis rates of ETF were not always reflected in greater protein abundance. Greater synthesis of ETF during HFD indicates mitochondrial remodeling which may contribute higher mitochondrial lipid respiration through enhanced ETF function.
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Affiliation(s)
- Philip M. Batterson
- School of Biological and Population Health SciencesOregon State UniversityCorvallisOregonUSA
| | - Erin M. McGowan
- School of Biological and Population Health SciencesOregon State UniversityCorvallisOregonUSA
| | - Agnieszka K. Borowik
- Aging and Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOklahomaUSA
| | - Michael T. Kinter
- Aging and Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOklahomaUSA
| | - Benjamin F. Miller
- Aging and Metabolism Research ProgramOklahoma Medical Research FoundationOklahoma CityOklahomaUSA
- Oklahoma City VAOklahoma CityOklahomaUSA
| | - Sean A. Newsom
- School of Biological and Population Health SciencesOregon State UniversityCorvallisOregonUSA
| | - Matthew M. Robinson
- School of Biological and Population Health SciencesOregon State UniversityCorvallisOregonUSA
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Jonsson WO, Borowik AK, Pranay A, Kinter MT, Mirek ET, Levy JL, Snyder EM, Miller BF, Anthony TG. Kinetic proteomics identifies targeted changes in liver metabolism and the ribo-interactome by dietary sulfur amino acid restriction. GeroScience 2023; 45:2425-2441. [PMID: 36976488 PMCID: PMC10651627 DOI: 10.1007/s11357-023-00758-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/19/2023] [Indexed: 03/29/2023] Open
Abstract
Dietary sulfur amino acid restriction (SAAR) protects against diet-induced obesity, extends healthspan, and coincides with an overall reduction in hepatic protein synthesis. To explore the underpinnings of SAAR-induced slowed growth and its impact on liver metabolism and proteostasis, we resolved changes in hepatic mRNA and protein abundances and compared synthesis rates of individual liver proteins. To achieve this, adult male mice were provided deuterium-labeled drinking water while freely consuming either a regular-fat or high-fat diet that was SAA restricted. Livers from these mice and their respective dietary controls were used to conduct transcriptomic, proteomic, and kinetic proteomic analyses. We found that remodeling of the transcriptome by SAAR was largely agnostic to dietary fat content. Shared signatures included activation of the integrated stress response alongside alterations in metabolic processes impacting lipids, fatty acids, and amino acids. Changes to the proteome correlated poorly with the transcriptome, and yet, functional clustering of kinetic proteomic changes in the liver during SAAR revealed that the management of fatty acids and amino acids were altered to support central metabolism and redox balance. Dietary SAAR also strongly influenced the synthesis rates of ribosomal proteins and ribosome-interacting proteins regardless of dietary fat. Taken together, dietary SAAR alters the transcriptome and proteome in the liver to safely manage increased fatty acid flux and energy use and couples this with targeted changes in the ribo-interactome to support proteostasis and slowed growth.
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Affiliation(s)
- William O Jonsson
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Michael T Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Emily T Mirek
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Jordan L Levy
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA
| | - Elizabeth M Snyder
- Department of Animal Sciences, Rutgers University, New Brunswick, NJ, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
- Oklahoma City VA, Oklahoma City, OK, USA
| | - Tracy G Anthony
- Department of Nutritional Sciences and the New Jersey Institute for Food, Nutrition and Health, Rutgers University, 59 Dudley Road - Foran Hall, Room 166, New Brunswick, NJ, 08901, USA.
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7
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Bruns DR, McNair BD, Peelor FF, Borowik AK, Pranay A, Yusifov A, Miller BF. Skeletal and cardiac muscle have different protein turnover responses in a model of right heart failure. GeroScience 2023; 45:2545-2557. [PMID: 37118350 PMCID: PMC10651599 DOI: 10.1007/s11357-023-00777-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 03/20/2023] [Indexed: 04/30/2023] Open
Abstract
Right heart failure (RHF) is a common and deadly disease in aged populations. Extra-cardiac outcomes of RHF such as skeletal muscle atrophy contribute to morbidity and mortality. Despite the significance of maintaining right ventricular (RV) and muscle function, the mechanisms of RHF and muscle atrophy are unclear. Metformin (MET) improves cardiac and muscle function through the regulation of metabolism and the cellular stress response. However, whether MET is a viable therapeutic for RHF and muscle atrophy is not yet known. We used deuterium oxide labeling to measure individual protein turnover in the RV as well as subcellular skeletal muscle proteostasis in aged male mice subjected to 4 weeks of hypobaric hypoxia (HH)-induced RHF. Mice exposed to HH had elevated RV mass and impaired RV systolic function, neither of which was prevented by MET. HH resulted in a higher content of glycolytic, cardiac, and antioxidant proteins in the RV, most of which were inhibited by MET. The synthesis of these key RV proteins was generally unchanged by MET, suggesting MET accelerated protein breakdown. HH resulted in a loss of skeletal muscle mass due to inhibited protein synthesis alongside myofibrillar protein breakdown. MET did not impact HH-induced muscle protein turnover and did not prevent muscle wasting. Together, we show tissue-dependent responses to HH-induced RHF where the RV undergoes hypertrophic remodeling with higher expression of metabolic and stress response proteins. Skeletal muscle undergoes loss of protein mass and atrophy, primarily due to myofibrillar protein breakdown. MET did not prevent HH-induced RV dysfunction or muscle wasting, suggesting that the identification of other therapies to attenuate RHF and concomitant muscle atrophy is warranted.
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Affiliation(s)
- Danielle R Bruns
- Division of Kinesiology & Health, University of Wyoming, 1000 E. University Ave, Dept. 3196, Laramie, WY, 82071, USA.
- Wyoming WWAMI Medical Education, Laramie, WY, USA.
| | - Benjamin D McNair
- Division of Kinesiology & Health, University of Wyoming, 1000 E. University Ave, Dept. 3196, Laramie, WY, 82071, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Atul Pranay
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Aykhan Yusifov
- Division of Kinesiology & Health, University of Wyoming, 1000 E. University Ave, Dept. 3196, Laramie, WY, 82071, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
- Oklahoma City VA Medical Center, Oklahoma City, OK, USA
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8
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Bubak MP, Mann SN, Borowik AK, Pranay A, Batushansky A, Mondal SA, Diodge SM, Davidyan A, Szczygiel MM, Peelor FR, Rigsby S, Broomfield M, Lacy CI, Rice HC, Stout MB, Miller BF. 17α-estradiol Alleviates High-Fat Diet-Induced Inflammatory and Metabolic Dysfunction in Skeletal Muscle of Male and Female Mice. bioRxiv 2023:2023.05.30.542870. [PMID: 37398463 PMCID: PMC10312580 DOI: 10.1101/2023.05.30.542870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Skeletal muscle has a central role in maintaining metabolic homeostasis. 17α-estradiol (17α-E2), a naturally-occurring non-feminizing diastereomer of 17β-estradiol that demonstrates efficacy for improving metabolic outcomes in male, but not female, mice. Despite several lines of evidence showing that 17α-E2 treatment improves metabolic parameters in middle-aged obese and old male mice through effects in brain, liver, and white adipose tissue little is known about how 17α-E2 alters skeletal muscle metabolism, and what role this may play in mitigating metabolic declines. Therefore, this study aimed to determine if 17α-E2 treatment improves metabolic outcomes in skeletal muscle from obese male and female mice following chronic high fat diet (HFD) administration. We hypothesized that male, but not female, mice, would benefit from 17α-E2 treatment during HFD. To test this hypothesis, we used a multi-omics approach to determine changes in lipotoxic lipid intermediates, metabolites, and proteins related to metabolic homeostasis. In male mice, we show that 17α-E2 alleviates HFD-induced metabolic detriments of skeletal muscle by reducing the accumulation of diacylglycerol (DAGs) and ceramides, inflammatory cytokine levels, and reduced the abundance of most of the proteins related to lipolysis and beta-oxidation. In contrast to males, 17α-E2 treatment in female mice had little effect on the DAGs and ceramides content, muscle inflammatory cytokine levels, or changes to the relative abundance of proteins involved in beta-oxidation. These data support to the growing evidence that 17α-E2 treatment could be beneficial for overall metabolic health in male mammals.
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9
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Borowik AK, Davidyan A, Peelor FF, Voloviceva E, Doidge SM, Bubak MP, Mobley CB, McCarthy JJ, Dupont-Versteegden EE, Miller BF. Skeletal Muscle Nuclei in Mice are not Post-mitotic. Function (Oxf) 2022; 4:zqac059. [PMID: 36569816 PMCID: PMC9772608 DOI: 10.1093/function/zqac059] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 11/15/2022] [Accepted: 11/16/2022] [Indexed: 11/23/2022] Open
Abstract
The skeletal muscle research field generally accepts that nuclei in skeletal muscle fibers (ie, myonuclei) are post-mitotic and unable to proliferate. Because our deuterium oxide (D2O) labeling studies showed DNA synthesis in skeletal muscle tissue, we hypothesized that resident myonuclei can replicate in vivo. To test this hypothesis, we used a mouse model that temporally labeled myonuclei with GFP followed by D2O labeling during normal cage activity, functional overload, and with satellite cell ablation. During normal cage activity, we observed deuterium enrichment into myonuclear DNA in 7 out of 7 plantaris (PLA), 6 out of 6 tibialis anterior (TA), 5 out of 7 gastrocnemius (GAST), and 7 out of 7 quadriceps (QUAD). The average fractional synthesis rates (FSR) of DNA in myonuclei were: 0.0202 ± 0.0093 in PLA, 0.0239 ± 0.0040 in TA, 0.0076 ± 0. 0058 in GAST, and 0.0138 ± 0.0039 in QUAD, while there was no replication in myonuclei from EDL. These FSR values were largely reproduced in the overload and satellite cell ablation conditions, although there were higher synthesis rates in the overloaded PLA muscle. We further provided evidence that myonuclear replication is through endoreplication, which results in polyploidy. These novel findings contradict the dogma that skeletal muscle nuclei are post-mitotic and open potential avenues to harness the intrinsic replicative ability of myonuclei for muscle maintenance and growth.
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Affiliation(s)
- Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
| | - Arik Davidyan
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
- Department of Biological Sciences, California State University Sacramento, 6000 J Street, Sacramento, CA, 95819, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
| | - Evelina Voloviceva
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
| | - Stephen M Doidge
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
| | - Matthew P Bubak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
| | | | - John J McCarthy
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40506, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40506, USA
| | - Esther E Dupont-Versteegden
- Center for Muscle Biology, University of Kentucky, Lexington, KY 40506, USA
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY, 40506, USA
- Department of Physical Therapy, College of Health Sciences, University of Kentucky, 900 S Limestone, Lexington, KY 40536, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th St, Oklahoma City, OK 73104, USA
- Oklahoma City VA Medical Center, 921 NE 13th St, Oklahoma City, OK 73104, USA
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10
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Thadathil N, Selvarani R, Mohammed S, Nicklas EH, Tran AL, Kamal M, Luo W, Brown JL, Lawrence MM, Borowik AK, Miller BF, Van Remmen H, Richardson A, Deepa SS. Senolytic treatment reduces cell senescence and necroptosis in Sod1 knockout mice that is associated with reduced inflammation and hepatocellular carcinoma. Aging Cell 2022; 21:e13676. [PMID: 35869934 PMCID: PMC9381894 DOI: 10.1111/acel.13676] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/20/2022] [Accepted: 07/03/2022] [Indexed: 02/06/2023] Open
Abstract
The goal of this study was to test the role cellular senescence plays in the increased inflammation, chronic liver disease, and hepatocellular carcinoma seen in mice null for Cu/Zn-Superoxide dismutase (Sod1KO). To inhibit senescence, wildtype (WT) and Sod1KO mice were given the senolytics, dasatinib, and quercetin (D + Q) at 6 months of age when the Sod1KO mice begin exhibiting signs of accelerated aging. Seven months of D + Q treatment reduced the expression of p16 in the livers of Sod1KO mice to WT levels and the expression of several senescence-associated secretory phenotype factors (IL-6, IL-1β, CXCL-1, and GDF-15). D + Q treatment also reduced markers of inflammation in livers of the Sod1KO mice, for example, cytokines, chemokines, macrophage levels, and Kupffer cell clusters. D + Q treatment had no effect on various markers of liver fibrosis in the Sod1KO mice but reduced the expression of genes involved in liver cancer and dramatically reduced the incidence of hepatocellular carcinoma. Surprisingly, D + Q also reduced markers of necroptosis (phosphorylated and oligomerized MLKL) in the Sod1KO mice to WT levels. We also found that inhibiting necroptosis in the Sod1KO mice with necrostatin-1s reduced the markers of cellular senescence (p16, p21, and p53). Our study suggests that an interaction occurs between cellular senescence and necroptosis in the liver of Sod1KO mice. We propose that these two cell fates interact through a positive feedback loop resulting in a cycle amplifying both cellular senescence and necroptosis leading to inflammaging and age-associated pathology in the Sod1KO mice.
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Affiliation(s)
- Nidheesh Thadathil
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Ramasamy Selvarani
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Sabira Mohammed
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA,Stephenson Cancer CenterUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Evan H. Nicklas
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Albert L. Tran
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Maria Kamal
- Department of PathologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Wenyi Luo
- Department of PathologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Jacob L. Brown
- Aging & Metabolism Program, Oklahoma Medical Research FoundationOklahoma CityOklahomaUSA,Oklahoma City VA Medical CenterOklahoma CityOklahomaUSA
| | - Marcus M. Lawrence
- Aging & Metabolism Program, Oklahoma Medical Research FoundationOklahoma CityOklahomaUSA,Department of Kinesiology and Outdoor RecreationSouthern Utah UniversityCedar CityUtahUSA
| | - Agnieszka K. Borowik
- Aging & Metabolism Program, Oklahoma Medical Research FoundationOklahoma CityOklahomaUSA
| | - Benjamin F. Miller
- Aging & Metabolism Program, Oklahoma Medical Research FoundationOklahoma CityOklahomaUSA,Oklahoma City VA Medical CenterOklahoma CityOklahomaUSA,Center for Geroscience and Healthy Brain AgingUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Holly Van Remmen
- Aging & Metabolism Program, Oklahoma Medical Research FoundationOklahoma CityOklahomaUSA,Oklahoma City VA Medical CenterOklahoma CityOklahomaUSA,Center for Geroscience and Healthy Brain AgingUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Arlan Richardson
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA,Stephenson Cancer CenterUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA,Oklahoma City VA Medical CenterOklahoma CityOklahomaUSA,Center for Geroscience and Healthy Brain AgingUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
| | - Sathyaseelan S. Deepa
- Department of Biochemistry & Molecular BiologyUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA,Stephenson Cancer CenterUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA,Center for Geroscience and Healthy Brain AgingUniversity of Oklahoma Health Sciences CenterOklahoma CityOklahomaUSA
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11
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Borowik AK, Peelor FF, Dupont‐Versteegden EE, McCarthy JJ, Miller BF. Myonuclei Can Replicate DNA. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r5037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Esther E. Dupont‐Versteegden
- Department of Physical TherapyUniversity of KentuckyLexingtonKY
- Center for Muscle BiologyUniversity of KentuckyLexingtonKY
| | - John J. McCarthy
- Center for Muscle BiologyUniversity of KentuckyLexingtonKY
- Department of PhysiologyUniversity of KentuckyLexingtonKY
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12
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Fuqua JD, Lawrence MM, Hettinger Z, Borowik AK, Peelor FF, Confides AL, Dupont‐Versteegden EE, Miller BF. Impaired Proteostasis, not Protein Synthesis, Limits Recovery of Aged Skeletal Muscle After Disuse Atrophy. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r3524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jordan D. Fuqua
- Aging & MetabolismOklahoma Medical Research FoundationOklahoma CityOK
| | - Marcus M. Lawrence
- Oklahoma Medical Research FoundationOklahoma CityOK
- Kinesiology and Outdoor RecreationOklahoma Medical Research FoundationOklahoma CityOK
| | - Zachary Hettinger
- Physical TherapyUniversity of KentuckyLexingtonKY
- Center for Muscle BiologyUniversity of KentuckyLexingtonKY
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13
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Kobak KA, Batushansky A, Borowik AK, Lopes EPB, Peelor III FF, Donovan EL, Kinter MT, Miller BF, Griffin TM. An In Vivo Stable Isotope Labeling Method to Investigate Individual Matrix Protein Synthesis, Ribosomal Biogenesis, and Cellular Proliferation in Murine Articular Cartilage. Function (Oxf) 2022; 3:zqac008. [PMID: 35399495 PMCID: PMC8991031 DOI: 10.1093/function/zqac008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/28/2022] [Accepted: 02/17/2022] [Indexed: 02/04/2023]
Abstract
Targeting chondrocyte dynamics is a strategy for slowing osteoarthritis progression during aging. We describe a stable-isotope method using in vivo deuterium oxide labeling and mass spectrometry to measure protein concentration, protein half-life, cell proliferation, and ribosomal biogenesis in a single sample of murine articular cartilage. We hypothesized that a 60-d labeling period would capture age-related declines in cartilage matrix protein content, protein synthesis rates, and cellular proliferation. Knee cartilage was harvested to the subchondral bone from 25- to 90-wk-old female C57BL/6J mice treated with deuterium oxide for 15, 30, 45, and 60 d. We measured protein concentration and half-lives using targeted high resolution accurate mass spectrometry and d2ome data processing software. Deuterium enrichment was quantified in isolated DNA and RNA to measure cell proliferation and ribosomal biogenesis, respectively. Most collagen isoforms were less abundant in aged animals, with negligible collagen synthesis at either age. In contrast, age altered the concentration and half-lives of many proteoglycans and other matrix proteins, including several with greater concentration and half-lives in older mice such as proteoglycan 4, clusterin, and fibronectin-1. Cellular proteins were less abundant in older animals, consistent with reduced cellularity. Nevertheless, deuterium was maximally incorporated into 60% of DNA and RNA by 15 d of labeling in both age groups, suggesting the presence of two large pools of either rapidly (<15 d) or slowly (>60 d) proliferating cells. Our findings indicate that age-associated changes in cartilage matrix protein content and synthesis occur without detectable changes in the relative number of proliferating cells.
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Affiliation(s)
- Kamil A Kobak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA,Institute of Heart Diseases, Wroclaw Medical University, Wroclaw 50-367, Poland
| | | | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Erika Prado Barboza Lopes
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Frederick F Peelor III
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | | | - Michael T Kinter
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
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14
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Kobak KA, Lawrence MM, Pharaoh G, Borowik AK, Peelor FF, Shipman PD, Griffin TM, Van Remmen H, Miller BF. Determining the contributions of protein synthesis and breakdown to muscle atrophy requires non-steady-state equations. J Cachexia Sarcopenia Muscle 2021; 12:1764-1775. [PMID: 34418329 PMCID: PMC8718081 DOI: 10.1002/jcsm.12772] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 06/17/2021] [Accepted: 07/10/2021] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Ageing and cachexia cause a loss of muscle mass over time, indicating that protein breakdown exceeds protein synthesis. Deuterium oxide (D2 O) is used for studies of protein turnover because of the advantages of long-term labelling, but these methods introduce considerations that have been largely overlooked when studying conditions of protein gain or loss. The purpose of this study was to demonstrate the importance of accounting for a change in protein mass, a non-steady state, during D2 O labelling studies while also exploring the contribution of protein synthesis and breakdown to denervation-induced muscle atrophy. METHODS Adult (6 months) male C57BL/6 mice (n = 14) were labelled with D2 O for a total of 7 days following unilateral sciatic nerve transection to induce denervation of hindlimb muscles. The contralateral sham limb and nonsurgical mice (n = 5) were used as two different controls to account for potential crossover effects of denervation. We calculated gastrocnemius myofibrillar and collagen protein synthesis and breakdown assuming steady-state or using non-steady-state modelling. We measured RNA synthesis rates to further understand ribosomal turnover during atrophy. RESULTS Gastrocnemius mass was less in denervated muscle (137 ± 9 mg) compared with sham (174 ± 15 mg; P < 0.0001) or nonsurgical control (162 ± 5 mg; P < 0.0001). With steady-state calculations, fractional synthesis and breakdown rates (FSR and FBR) were lower in the denervated muscle (1.49 ± 0.06%/day) compared with sham (1.81 ± 0.09%/day; P < 0.0001) or nonsurgical control (2.27 ± 0.04%/day; P < 0.0001). When adjusting for change in protein mass, FSR was 4.21 ± 0.19%/day in denervated limb, whereas FBR was 4.09 ± 0.22%/day. When considering change in protein mass (ksyn ), myofibrillar synthesis was lower in denervated limb (2.44 ± 0.14 mg/day) compared with sham (3.43 ± 0.22 mg/day; P < 0.0001) and non-surgical control (3.74 ± 0.12 mg/day; P < 0.0001), whereas rate of protein breakdown (kdeg, 1/t) was greater in denervated limb (0.050 ± 0.003) compared with sham (0.019 ± 0.001; P < 0.0001) and nonsurgical control (0.023 ± 0.000; P < 0.0001). Muscle collagen breakdown was completely inhibited during denervation. There was a strong correlation (r = 0.83, P < 0.001) between RNA and myofibrillar protein synthesis in sham but not denervated muscle. CONCLUSIONS We show conflicting results between steady- and non-steady-state calculations on myofibrillar protein synthesis and breakdown during periods of muscle loss. We also found that collagen accumulation was largely from a decrease in collagen breakdown. Comparison between sham and non-surgical control demonstrated a crossover effect of denervation on myofibrillar protein synthesis and ribosomal biogenesis, which impacts study design for unilateral atrophy studies. These considerations are important because not accounting for them can mislead therapeutic attempts to maintain muscle mass.
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Affiliation(s)
- Kamil A Kobak
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Laboratory for Applied Research on Cardiovascular System, Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland
| | - Marcus M Lawrence
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Department of Kinesiology and Outdoor Recreation, Southern Utah University, Cedar City, UT, USA
| | - Gavin Pharaoh
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Agnieszka K Borowik
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Frederick F Peelor
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Patrick D Shipman
- Department of Mathematics, Colorado State University, Fort Collins, CO, USA
| | - Timothy M Griffin
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Holly Van Remmen
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA.,Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Benjamin F Miller
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
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