Medicine and Health Sciences Commons^™

Modulating Tumour Hypoxia In Prostate Cancer Through Exercise: The Impact Of Redox Signalling On Radiosensitivity, Malcolm Brown, Amélie Rébillard, Nicolas H. Hart, Dominic O’Connor, Gillian Prue, Joe M. O’Sullivan, Suneil Jain

Research outputs 2022 to 2026

Prostate cancer is a complex disease affecting millions of men globally. Radiotherapy (RT) is a common treatment modality although treatment efficacy is dependent upon several features within the tumour microenvironment (TME), especially hypoxia. A hypoxic TME heightens radioresistance and thus disease recurrence and treatment failure continues to pose important challenges. However, the TME evolves under the influence of factors in systemic circulation and cellular crosstalk, underscoring its potential to be acutely and therapeutically modified. Early preclinical evidence suggests exercise may affect tumour growth and some of the benefits drawn, could act to radiosensitise tumours to treatment. Intracellular perturbations in skeletal …

In Vivo Ps-Oct Needle Probe Scan Of Human Skeletal Muscle, Jeffrey M. Mcbride, Michael J. Hackmann, Sophia Nimphius, Barry Cense

Research outputs 2022 to 2026

Polarization-sensitive optical coherence tomography (PS-OCT) derived birefringence values effectively identify skeletal muscle structural disruption due to muscular dystrophy and exercise-related muscle damage in animal models in ex vivo tissue. The purpose of this investigation was to determine if a PS-OCT needle probe inserted into the leg of a human subject could accurately identify various anatomical structures with implications for use as a diagnostic tool for the determination of skeletal muscle pathology. A healthy middle-aged subject participated in this study. A custom-built PS-OCT system was interfaced with a side-viewing fiber-optic needle probe inserted into the subject's vastus lateralis muscle via a …

The Influence Of Shoe And Cleat Type On Lower Extremity Muscle Activation In Youth Baseball Pitchers, Jacob R. Gdovin, Chip Wade, Lauren A. Luginsland, Charles C. Williams, Riley Galloway, John C. Garner

Human Movement Sciences & Special Education Faculty Publications

Background: Baseball pitching is a dynamic movement where the lower extremities generate and sequentially transfer energy to the upper extremities to maximize ball velocity. The need for lower body muscular strength to produce adequate push-off and landing forces has been documented; however, the influence footwear and surface inclination has on muscle activation remains unknown.

Objectives: Determine how pitching in molded cleats and turf shoes from a pitching mound and flat ground affects stride-leg muscle activation in youth baseball pitchers while determining percent activation during each pitching phase.

Methods: Cross – sectional study analyzing mean muscle activity and percent activation of …

Deletion Of Sa Β-Gal+ Cells Using Senolytics Improves Muscle Regeneration In Old Mice, Cory M. Dungan, Kevin A. Murach, Christopher J. Zdunek, Zuo Jian Tang, Georgia L. Vonlehmden, Camille R. Brightwell, Zachary Hettinger, Davis A. Englund, Zheng Liu, Christopher S. Fry, Antonio Filareto, Michael Franti, Charlotte A. Peterson

Physical Therapy Faculty Publications

Systemic deletion of senescent cells leads to robust improvements in cognitive, cardiovascular, and whole-body metabolism, but their role in tissue reparative processes is incompletely understood. We hypothesized that senolytic drugs would enhance regeneration in aged skeletal muscle. Young (3 months) and old (20 months) male C57Bl/6J mice were administered the senolytics dasatinib (5 mg/kg) and quercetin (50 mg/kg) or vehicle bi-weekly for 4 months. Tibialis anterior (TA) was then injected with 1.2% BaCl₂ or PBS 7- or 28 days prior to euthanization. Senescence-associated β-Galactosidase positive (SA β-Gal+) cell abundance was low in muscle from both young and old mice …

Activation Of Crtc2/Creb1 In Skeletal Muscle Enhances Weight Loss During Intermittent Fasting, Nelson E Bruno, Jerome C Nwachukwu, David C Hughes, Sathish Srinivasan, Richard Hawkins, David Sturgill, Gordon L Hager, Stephen Hurst, Shey-Shing Sheu, Sue C Bodine, Michael D Conkright, Kendall W Nettles

Department of Medicine Faculty Papers

The Creb-Regulated Transcriptional Coactivator (Crtc) family of transcriptional coregulators drive Creb1-mediated transcription effects on metabolism in many tissues, but the in vivo effects of Crtc2/Creb1 transcription on skeletal muscle metabolism are not known. Skeletal muscle-specific overexpression of Crtc2 (Crtc2 mice) induced greater mitochondrial activity, metabolic flux capacity for both carbohydrates and fats, improved glucose tolerance and insulin sensitivity, and increased oxidative capacity, supported by upregulation of key metabolic genes. Crtc2 overexpression led to greater weight loss during alternate day fasting (ADF), selective loss of fat rather than lean mass, maintenance of higher energy expenditure during the fast and reduced binge-eating …

Scaling Of Computed Tomography Body Composition To Height: Relevance Of Height-Normalized Indices In Patients With Colorectal Cancer, Justin C. Brown, Steven B. Heymsfield, Bette J. Caan

School of Medicine Faculty Publications

Background: Body weight scales to height with a power of ≈2 (weight/height2), forming the basis of body mass index (BMI). The corresponding scaling of body composition measured by abdominal computed tomography (CT) to height has not been established. The objective of this analysis was to quantify the scaling of body composition measured by a single-slice axial abdominal CT image (skeletal muscle, and visceral, subcutaneous, and total adipose tissue) to height in patients with colorectal cancer (CRC). Methods: This cross-sectional study included non-Hispanic white males and females, aged 18–80 years, who were diagnosed with stage I–III CRC at an integrated health …

Effect Of The Lysosomotropic Agent Chloroquine On Mtorc1 Activation And Protein Synthesis In Human Skeletal Muscle, Michael S. Borack, Jared M. Dickinson, Christopher S. Fry, Paul T. Reidy, Melissa M. Markofski, Rachel R. Deer, Kristofer Jennings, Elena Volpi, Blake B. Rasmussen

Athletic Training and Clinical Nutrition Faculty Publications

BACKGROUND: Previous work in HEK-293 cells demonstrated the importance of amino acid-induced mTORC1 translocation to the lysosomal surface for stimulating mTORC1 kinase activity and protein synthesis. This study tested the conservation of this amino acid sensing mechanism in human skeletal muscle by treating subjects with chloroquine-a lysosomotropic agent that induces in vitro and in vivo lysosome dysfunction.

METHODS: mTORC1 signaling and muscle protein synthesis (MPS) were determined in vivo in a randomized controlled trial of 14 subjects (10 M, 4 F; 26 ± 4 year) that ingested 10 g of essential amino acids (EAA) after receiving 750 mg of chloroquine …

A Research Update: Significance Of Cytokine Storm And Diaphragm In Covid-19, Ashwani Mittal, Anita Dua, Sanjeev Gupta, Elisha Injeti

Pharmaceutical Sciences Faculty Publications

Emerging research on severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) shows that it is spreading to multiple organs in addition to the respiratory system. Though the SARS-CoV2 enters the human body by binding to ACE2 receptors on pulmonary alveolar cells, recent studies indicate that it is spreading to the central nervous system, cardiac and skeletal muscles leading to various pathological conditions in these organs. In particular, the effects of SARS-CoV-2 on triggering the cytokine storm and its consequential effects on skeletal muscles has generated a lot of discussion. The effects of this virus on muscular function especially in susceptible elderly populations …

Lat1 Protein Content Increases Following 12 Weeks Of Resistance Exercise Training In Human Skeletal Muscle, Paul A. Roberson, Christopher Brooks Mobley, Matthew A. Romero, Cody T. Haun, Shelby C. Osburn, Petey W. Mumford, Christopher G. Vann, Rory A. Greer, Arny A. Ferrando, Michael D. Roberts

Physiology Faculty Publications

Introduction: Amino acid transporters are essential for cellular amino acid transport and promoting protein synthesis. While previous literature has demonstrated the association of amino acid transporters and protein synthesis following acute resistance exercise and amino acid supplementation, the chronic effect of resistance exercise and supplementation on amino acid transporters is unknown. The purpose herein was to determine if amino acid transporters and amino acid metabolic enzymes were related to skeletal muscle hypertrophy following resistance exercise training with different nutritional supplementation strategies.

Methods: 43 college-aged males were separated into a maltodextrin placebo (PLA, n = 12), leucine (LEU, n = 14), …

The Acute Effects Of 5 Fluorouracil On Skeletal Muscle Resident And Infiltrating Immune Cells In Mice, Brandon N. Vanderveen, Alexander T. Sougiannis, Kandy T. Velazquez, James A. Carson, Daping Fan, E. Angela Murphy

Faculty Publications

5 fluorouracil (5FU) has been a first-choice chemotherapy drug for several cancer types (e.g., colon, breast, head, and neck); however, its efficacy is diminished by patient acquired resistance and pervasive side effects. Leukopenia is a hallmark of 5FU; however, the impact of 5FU-induced leukopenia on healthy tissue is only becoming unearthed. Recently, skeletal muscle has been shown to be impacted by 5FU in clinical and preclinical settings and weakness and fatigue remain among the most consistent complaints in cancer patients undergoing chemotherapy. Monocytes, or more specifically macrophages, are the predominate immune cell in skeletal muscle which regulate turnover and homeostasis …

Effect Of High-Dose Vs Standard-Dose Vitamin D Supplementation On Body Composition Among Patients With Advanced Or Metastatic Colorectal Cancer: A Randomized Trial, Justin C. Brown, Michael H. Rosenthal, Chao Ma, Sui Zhang, Halla S. Nimeiri, Nadine J. Mccleary, Thomas A. Abrams, Matthew B. Yurgelun, James M. Cleary, Douglas A. Rubinson, Deborah Schrag, Andrea J. Bullock, Jill Allen, Dan Zuckerman, Emily Chan, Jennifer A. Chan, Brian Wolpin, Michael Constantine

School of Medicine Faculty Publications

Skeletal muscle and adipose tissue express the vitamin D receptor and may be a mechanism through which vitamin D supplementation slows cancer progression and reduces cancer death. In this exploratory analysis of a double-blind, multicenter, randomized phase II clinical trial, 105 patients with advanced or metastatic colorectal cancer who were receiving chemotherapy were randomized to either high-dose vitamin D3 (4000 IU) or standard-dose (400 IU) vitamin D3. Body composition was measured with abdominal computed tomography at enrollment (baseline) and after cycle 8 of chemotherapy (16 weeks). As compared with standard-dose vitamin D3, high-dose vitamin D3 did not significantly change body …

Correlations Of Calf Muscle Macrophage Content With Muscle Properties And Walking Performance In Peripheral Artery Disease, Kate Kosmac, Marta Gonzalez-Freire, Mary M. Mcdermott, Sarah H. White, R. Grace Walton, Robert L. Sufit, Lu Tian, Lingyu Li, Melina R. Kibbe, Michael H Criqui, Jack M. Guralnik, Tamar S. Polonsky, Christiaan Leeuwenburgh, Luigi Ferrucci, Charlotte A. Peterson

Physical Therapy Faculty Publications

Background

Peripheral artery disease (PAD) is a manifestation of atherosclerosis characterized by reduced blood flow to the lower extremities and mobility loss. Preliminary evidence suggests PAD damages skeletal muscle, resulting in muscle impairments that contribute to functional decline. We sought to determine whether PAD is associated with an altered macrophage profile in gastrocnemius muscles and whether muscle macrophage populations are associated with impaired muscle phenotype and walking performance in patients with PAD.

Methods and Results

Macrophages, satellite cells, and extracellular matrix in gastrocnemius muscles from 25 patients with PAD and 7 patients without PAD were quantified using immunohistochemistry. Among patients …

Commercial Genetic Testing For Type 2 Polysaccharide Storage Myopathy And Myofibrillar Myopathy Does Not Correspond To A Histopathological Diagnosis, Stephanie J. Valberg, C. J. Finno, Marisa L. Henry, Melissa Schott, Deborah Velez-Irizarry, Sichong Peng, Erica C. Mckenzie, Jessica L. Petersen

Department of Animal Science: Faculty Publications

Background: Commercial genetic tests for type 2 polysaccharide storage myopathy (PSSM2) and myofibrillar myopathy (MFM) have not been validated by peer-review, and formal regulation of veterinary genetic testing is lacking.

Objectives: To compare genotype and allele frequencies of commercial test variants (P variants) in MYOT (P2; rs1138656462), FLNC (P3a; rs1139799323), FLNC (P3b; rs1142918816) and MYOZ3 (P4; rs1142544043) between Warmblood (WB) and Arabian (AR) horses diagnosed with PSSM2/MFM by muscle histopathology, and phenotyped breed-matched controls. To quantify variant frequency in public repositories of ancient and modern horse breeds.

Study design: Cross sectional using archived clinical material and publicly available data.

Methods: …

Bioenergetic Functions In Subpopulations Of Heart Mitochondria Are Preserved In A Non-Obese Type 2 Diabetes Rat Model (Goto-Kakizaki), Nicola Lai, C. M. Kummitha, F. Loy, R. Isola, C. L. Hoppel

Electrical & Computer Engineering Faculty Publications

A distinct bioenergetic impairment of heart mitochondrial subpopulations in diabetic cardiomyopathy is associated with obesity; however, many type 2 diabetic (T2DM) patients with high-risk for cardiovascular disease are not obese. In the absence of obesity, it is unclear whether bioenergetic function in the subpopulations of mitochondria is affected in heart with T2DM. To address this issue, a rat model of non-obese T2DM was used to study heart mitochondrial energy metabolism, measuring bioenergetics and enzyme activities of the electron transport chain (ETC). Oxidative phosphorylation in the presence of substrates for ETC and ETC activities in both populations of heart mitochondria in …

Whey Protein Supplementation Post Resistance Exercise In Elderly Men Induces Changes In Muscle Mirna's Compared To Resistance Exercise Alone, Randall F. D'Souza, Nina Zeng, James F. Markworth, Vandre C. Figueiredo, Christopher P. Hedges, Aaron C Petersen, Paul A Della Gatta, David Cameron-Smith, Cameron J. Mitchell

Center for Muscle Biology Faculty Publications

Progressive muscle loss with aging results in decreased physical function, frailty, and impaired metabolic health. Deficits in anabolic signaling contribute to an impaired ability for aged skeletal muscle to adapt in response to exercise and protein feeding. One potential contributing mechanism could be exerted by dysregulation of microRNAs (miRNAs). Therefore, the aim of this study was to determine if graded protein doses consumed after resistance exercise altered muscle miRNA expression in elderly men. Twenty-three senior men (67.9 ± 0.9 years) performed a bout of resistance exercise and were randomized to consume either a placebo, 20 or 40 g of whey …

Local In Vivo Measures Of Muscle Lipid And Oxygen Consumption Change In Response To Combined Vitamin D Repletion And Aerobic Training In Older Adults, D. Travis Thomas, David M. Schnell, Maja Redzic, Mingjun Zhao, Hideat Abraha, Danielle Jones, Howard Brim, Guoqiang Yu

Health and Clinical Sciences Faculty Publications

Intramyocellular (IMCL), extramyocellular lipid (EMCL), and vitamin D deficiency are associated with muscle metabolic dysfunction. This study compared the change in [IMCL]:[EMCL] following the combined treatment of vitamin D and aerobic training (DAT) compared with vitamin D (D), aerobic training (AT), and control (CTL). Male and female subjects aged 60–80 years with a BMI ranging from 18.5–34.9 and vitamin D status of ≤ 32 ng/mL (25(OH)D) were recruited to randomized, prospective clinical trial double-blinded for supplement with a 2 × 2 factorial design. Cholecalciferol (Vitamin D₃) (10,000 IU × 5 days/week) or placebo was provided for 13 weeks …

The Role Of Sirt1 In Skeletal Muscle Function And Repair Of Older Mice, Mathew J. Myers, Danielle L. Sheperd, Andrya J. Durr, David S. Stanton, Junaith S. Mohamed, John M. Hollander, Stephen E. Alway

Faculty & Staff Scholarship

Background Sirtuin 1 (SIRT1) is a NAD+ sensitive deacetylase that has been linked to longevity and has been suggested to confer beneficial effects that counter aging-associated deterioration. Muscle repair is dependent upon satellite cell function, which is reported to be reduced with aging; however, it is not known if this is linked to an aging-suppression of SIRT1. This study tested the hypothesis that Sirtuin 1 (SIRT1) overexpression would increase the extent of muscle repair and muscle function in older mice. Methods We examined satellite cell dependent repair in tibialis anterior, gastrocnemius, and soleus muscles of 13 young wild-type mice (20–30 …

Hif Prolyl Hydroxylase Inhibition Protects Skeletal Muscle From Eccentric Contraction-Induced Injury, Andrew N Billin, Samuel E Honeycutt, Alan V Mcdougal, Jaclyn P Kerr, Zhe Chen, Johannes M Freudenberg, Deepak K Rajpal, Guizhen Luo, Henning Fritz Kramer, Robert S Geske, Frank Fang, Bert Yao, Richard V Clark, John Lepore, Alex Cobitz, Ram Miller, Kazunori Nosaka, Aaron C Hinken, Alan J Russell

Research outputs 2014 to 2021

BACKGROUND: In muscular dystrophy and old age, skeletal muscle repair is compromised leading to fibrosis and fatty tissue accumulation. Therefore, therapies that protect skeletal muscle or enhance repair would be valuable medical treatments. Hypoxia-inducible factors (HIFs) regulate gene transcription under conditions of low oxygen, and HIF target genes EPO and VEGF have been associated with muscle protection and repair. We tested the importance of HIF activation following skeletal muscle injury, in both a murine model and human volunteers, using prolyl hydroxylase inhibitors that stabilize and activate HIF.

METHODS: Using a mouse eccentric limb injury model, we characterized the protective effects …

Autotaxin-Lpa Signaling Contributes To Obesity-Induced Insulin Resistance In Muscle And Impairs Mitochondrial Metabolism, Kenneth D'Souza, Carine Nzirorera, Andrew M. Cowie, Geena P. Varghese, Purvi Trivedi, Thomas O. Eichmann, Dipsikha Biswas, Mohamed Touaibia, Andrew J. Morris, Vassilis Aidinis, Daniel A. Kane, Thomas Pulinilkunnil, Petra C. Kienesberger

Internal Medicine Faculty Publications

Autotaxin (ATX) is an adipokine that generates the bioactive lipid, lysophosphatidic acid (LPA). ATX-LPA signaling has been implicated in diet-induced obesity and systemic insulin resistance. However, it remains unclear whether the ATX-LPA pathway influences insulin function and energy metabolism in target tissues, particularly skeletal muscle, the major site of insulin-stimulated glucose disposal. The objective of this study was to test whether the ATX-LPA pathway impacts tissue insulin signaling and mitochondrial metabolism in skeletal muscle during obesity. Male mice with heterozygous ATX deficiency (ATX^+/−) were protected from obesity, systemic insulin resistance, and cardiomyocyte dysfunction following high-fat high-sucrose (HFHS) feeding. …

Physiological Differences Between Low Versus High Skeletal Muscle Hypertrophic Responders To Resistance Exercise Training: Current Perspectives And Future Research Directions, Michael D. Roberts, Cody T. Haun, Christopher B. Mobley, Petey W. Mumford, Matthew A. Romero, Paul A. Roberson, Christopher G. Vann, John J. Mccarthy

Physiology Faculty Publications

Numerous reports suggest there are low and high skeletal muscle hypertrophic responders following weeks to months of structured resistance exercise training (referred to as low and high responders herein). Specifically, divergent alterations in muscle fiber cross sectional area (fCSA), vastus lateralis thickness, and whole body lean tissue mass have been shown to occur in high versus low responders. Differential responses in ribosome biogenesis and subsequent protein synthetic rates during training seemingly explain some of this individual variation in humans, and mechanistic in vitro and rodent studies provide further evidence that ribosome biogenesis is critical for muscle hypertrophy. High responders may …

Immunohistochemical Identification Of Human Skeletal Muscle Macrophages, Kate Kosmac, Bailey D. Peck, R. Grace Walton, Jyothi Mula, Philip A. Kern, Marcas M. Bamman, Richard A. Dennis, Cale A. Jacobs, Christian Lattermann, Darren L. Johnson, Charlotte A. Peterson

Physical Therapy Faculty Publications

Macrophages have well-characterized roles in skeletal muscle repair and regeneration. Relatively little is known regarding the role of resident macrophages in skeletal muscle homeostasis, extracellular matrix remodeling, growth, metabolism and adaptation to various stimuli including exercise and training. Despite speculation into macrophage contributions during these processes, studies characterizing macrophages in non-injured muscle are limited and methods used to identify macrophages vary. A standardized method for the identification of human resident skeletal muscle macrophages will aide in the characterization of these immune cells and allow for the comparison of results across studies. Here, we present an immunohistochemistry (IHC) protocol, validated by …

Transcriptional Profiling Reveals Extraordinary Diversity Among Skeletal Muscle Tissues, Erin E. Terry, Xiping Zhang, Christy Hoffmann, Laura D. Hughes, Scott A. Lewis, Jiajia Li, Matthew J. Wallace, Lance A. Riley, Collin M. Douglas, Miguel A. Gutierrez-Monreal, Nicholas F. Lahens, Ming C. Gong, Francisco H. Andrade, Karyn A. Esser, Michael E. Hughes

Physiology Faculty Publications

Skeletal muscle comprises a family of diverse tissues with highly specialized functions. Many acquired diseases, including HIV and COPD, affect specific muscles while sparing others. Even monogenic muscular dystrophies selectively affect certain muscle groups. These observations suggest that factors intrinsic to muscle tissues influence their resistance to disease. Nevertheless, most studies have not addressed transcriptional diversity among skeletal muscles. Here we use RNAseq to profile mRNA expression in skeletal, smooth, and cardiac muscle tissues from mice and rats. Our data set, MuscleDB, reveals extensive transcriptional diversity, with greater than 50% of transcripts differentially expressed among skeletal muscle tissues. We detect …

Oral Glucose Challenge Impairs Skeletal Muscle Microvascular Blood Flow In Healthy People, Ryan D. Russell, Donghua Hu, Timothy Greenaway, James E. Sharman, Stephen Rattigan, Stephen M. Richards, Michelle A. Keske

Health & Human Performance Faculty Publications and Presentations

Skeletal muscle microvascular (capillary) blood flow increases in the postprandial state or during insulin infusion due to dilation of precapillary arterioles to augment glucose disposal. This effect occurs independently of changes in large artery function. However, acute hyperglycemia impairs vascular function, causes insulin to vasoconstrict precapillary arterioles, and causes muscle insulin resistance in vivo. We hypothesized that acute hyperglycemia impairs postprandial muscle microvascular perfusion, without disrupting normal large artery hemodynamics, in healthy humans. Fifteen healthy people (5 F/10 M) underwent an oral glucose challenge (OGC, 50 g glucose) and a mixed-meal challenge (MMC) on two separate occasions (randomized, crossover design). …

Acute Resistance Exercise Induces Sestrin2 Phosphorylation And P62 Dephosphorylation In Human Skeletal Muscle, Nina Zeng, Randall F. D'Souza, Vandre C. Figueiredo, James F. Markworth, Llion A. Roberts, Jonathan M. Peake, Cameron J. Mitchell, David Cameron-Smith

Center for Muscle Biology Faculty Publications

Sestrins (1, 2, 3) are a family of stress-inducible proteins capable of attenuating oxidative stress, regulating metabolism, and stimulating autophagy. Sequestosome1 (p62) is also a stress-inducible multifunctional protein acting as a signaling hub for oxidative stress and selective autophagy. It is unclear whether Sestrin and p62^Ser403 are regulated acutely or chronically by resistance exercise (RE) or training (RT) in human skeletal muscle. Therefore, the acute and chronic effects of RE on Sestrin and p62 in human skeletal muscle were examined through two studies. In Study 1, nine active men (22.1 ± 2.2 years) performed a bout of single-leg strength …

The Gene Smart Study: Method, Study Design, And Preliminary Findings, Xu Yan, Nir Eynon, Ioannis D. Papadimitriou, Jujiao Kuang, Fiona Munson, Oren Tirosh, Lannie O’Keefe, Lyn R. Griffiths, Kevin J. Ashton, Nuala Byrne, Yannis P. Pitsiladis, David J. Bishop

Research outputs 2014 to 2021

The gene SMART (genes and the Skeletal Muscle Adaptive Response to Training) Study aims to identify genetic variants that predict the response to both a single session of High-Intensity Interval Exercise (HIIE) and to four weeks of High-Intensity Interval Training (HIIT). While the training and testing centre is located at Victoria University, Melbourne, three other centres have been launched at Bond University, Queensland University of Technology, Australia, and the University of Brighton, UK. Currently 39 participants have already completed the study and the overall aim is to recruit 200 moderately-trained, healthy Caucasians participants (all males 18 – 45 y, BMI …

Metformin To Augment Strength Training Effective Response In Seniors (Masters): Study Protocol For A Randomized Controlled Trial, Doug E. Long, Bailey D. Peck, Jenny L. Martz, S. Craig Tuggle, Heather M. Bush, Gerald Mcgwin, Philip A. Kern, Marcas M. Bamman, Charlotte A. Peterson

Clinical and Translational Science Faculty Publications

Background: Muscle mass and strength are strong determinants of a person's quality of life and functional independence with advancing age. While resistance training is the most effective intervention to combat age-associated muscle atrophy (sarcopenia), the ability of older adults to increase muscle mass and strength in response to training is blunted and highly variable. Thus, finding novel ways to complement resistance training to improve muscle response and ultimately quality of life among older individuals is critical. The purpose of this study is to determine whether a commonly prescribed medication called metformin can be repurposed to improve the response to resistance …

Metformin To Augment Strength Training Effective Response In Seniors (Masters): Study Protocol For A Randomized Controlled Trial, Douglas E. Long, Bailey D. Peck, Jenny L. Martz, S. Craig Tuggle, Heather M. Bush, Gerald Mcgwin, Philip A. Kern, Marcas M. Bamman, Charlotte A. Peterson

Physical Therapy Faculty Publications

Background: Muscle mass and strength are strong determinants of a person’s quality of life and functional independence with advancing age. While resistance training is the most effective intervention to combat age-associated muscle atrophy (sarcopenia), the ability of older adults to increase muscle mass and strength in response to training is blunted and highly variable. Thus, finding novel ways to complement resistance training to improve muscle response and ultimately quality of life among older individuals is critical. The purpose of this study is to determine whether a commonly prescribed medication called metformin can be repurposed to improve the response to resistance …

Micrornas, Heart Failure, And Aging: Potential Interactions With Skeletal Muscle, Kevin A. Murach, John J. Mccarthy

Center for Muscle Biology Faculty Publications

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression by targeting mRNAs for degradation or translational repression. MiRNAs can be expressed tissue specifically and are altered in response to various physiological conditions. It has recently been shown that miRNAs are released into the circulation, potentially for the purpose of communicating with distant tissues. This manuscript discusses miRNA alterations in cardiac muscle and the circulation during heart failure, a prevalent and costly public health issue. A potential mechanism for how skeletal muscle maladaptations during heart failure could be mediated by myocardium-derived miRNAs released to the circulation is presented. An overview …

Exercise To The Rescue: An Analysis Of Altered Metabolic Gene Regulation Post-Exercise In Lean And Obese Individuals, Brandon Mudd

Mahurin Honors College Capstone Experience/Thesis Projects

The skeletal muscle of obese individuals exhibits a depressed ability to metabolize fats. Exercise training is thought to rescue this dampened ability to metabolize fats; mediated by a coordinated increase in the expression of a network of genes that regulate metabolism and fuel utilization. The purpose of this study is to determine the exercise-induced regulation of metabolically important genes in lean and obese individuals. Muscle biopsies (one pre-exercise/baseline and one immediately post-exercise) were obtained from 4 lean (BF% 24.4 ± 5.5; 23.5 yrs ± 1.9) and 13 obese (BF% 39.7 ± 2.4; 26.1 yrs ± 2.3), age-matched, relatively young subjects, …

Muscle-Specific Loss Of Bmal1 Leads To Disrupted Tissue Glucose Metabolism And Systemic Glucose Homeostasis, Brianna D. Harfmann, Elizabeth Schroder, Maureen T. Kachman, Brian A. Hodge, Xiping Zhang, Karyn Esser

Center for Muscle Biology Faculty Publications

Background: Diabetes is the seventh leading cause of death in the USA, and disruption of circadian rhythms is gaining recognition as a contributing factor to disease prevalence. This disease is characterized by hyperglycemia and glucose intolerance and symptoms caused by failure to produce and/or respond to insulin. The skeletal muscle is a key insulin-sensitive metabolic tissue, taking up ~80 % of postprandial glucose. To address the role of the skeletal muscle molecular clock to insulin sensitivity and glucose tolerance, we generated an inducible skeletal muscle-specific Bmal1 ^−/− mouse (iMSBmal1 ^−/−).

Results: Progressive changes in body composition (decreases in …