Physiology Commons^™

Role Of Fat Content On The Structure And Function Of Human Skeletal Muscle, Joseph A. Gordon Iii

Doctoral Dissertations

Muscle size does not fully explain variations in muscle strength. Fat content has been implicated in muscle weakness, though this relationship remains unclear. The relationship between fat and strength may vary between scales (e.g., cellular, organ, and organism). The goal of this dissertation was to clarify the role of fat in the structure and function of muscle using in vitro and in vivo techniques across multiple scales in adults 21-45 years old. Study 1 tested the agreement of intramyocellular lipid (IMCL) content between oil red o (ORO) and magnetic resonance spectroscopy (MRS) techniques. These measures of IMCL were also compared …

Reduced Mitochondrial Dna And Oxphos Protein Content In Skeletal Muscle Of Children With Cerebral Palsy, Ferdinand Von Walden, Ivan J. Vechetti Jr., Davis A. Englund, Vandré C. Figueiredo, Rodrigo Fernandez-Gonzalo, Kevin A. Murach, Jessica Pingel, John J. Mccarthy, Per Stål, Eva Pontén

Physiology Faculty Publications

AIM: To provide a detailed gene and protein expression analysis related to mitochondrial biogenesis and assess mitochondrial content in skeletal muscle of children with cerebral palsy (CP).

METHOD: Biceps brachii muscle samples were collected from 19 children with CP (mean [SD] age 15y 4mo [2y 6mo], range 9-18y, 16 males, three females) and 10 typically developing comparison children (mean [SD] age 15y [4y], range 7-21y, eight males, two females). Gene expression (quantitative reverse transcription polymerase chain reaction [PCR]), mitochondrial DNA (mtDNA) to genomic DNA ratio (quantitative PCR), and protein abundance (western blotting) were analyzed. Microarray data sets (CP/aging/bed rest) were …

Mechanisms Of Statin Effects On Muscle And Neuronal Proteostasis, Daniel Yu

University Scholar Projects

Statins are widely prescribed and used chronically, but we know little about the effects on long-term protein homeostasis during stress and aging. Our aim was to quantify the effect of statins on stress-induced protein damage. We administered atorvastatin in a dose-response curve in Caenorhabditis elegans under naïve control conditions and in conditions of hypertonic and heat stress known to induce muscle damage measurable as countable puncta in a polyglutamine aggregation model of damage. We observed that there is significant polyglutamine aggregation variability among worms at baseline and thus further study requires within experiment baseline controls, per worm. Our results are …

Chronic Muscle Weakness And Mitochondrial Dysfunction In The Absence Of Sustained Atrophy In A Preclinical Sepsis Model, Allison M. Owen, Samir P. Patel, Jeffrey D. Smith, Beverly K. Balasuriya, Stephanie F. Mori, Gregory S. Hawk, Arnold J. Stromberg, Naohide Kuriyama, Masao Kaneki, Alexander G. Rabchevsky, Timothy A. Butterfield, Karyn A. Esser, Charlotte A. Peterson, Marlene E. Starr, Hiroshi Saito

Physiology Faculty Publications

Chronic critical illness is a global clinical issue affecting millions of sepsis survivors annually. Survivors report chronic skeletal muscle weakness and development of new functional limitations that persist for years. To delineate mechanisms of sepsis-induced chronic weakness, we first surpassed a critical barrier by establishing a murine model of sepsis with ICU-like interventions that allows for the study of survivors. We show that sepsis survivors have profound weakness for at least 1 month, even after recovery of muscle mass. Abnormal mitochondrial ultrastructure, impaired respiration and electron transport chain activities, and persistent protein oxidative damage were evident in the muscle of …

Phase- Specific Changes In Rate Of Force Development And Muscle Morphology Throughout A Block Periodized Training Cycle In Weightlifters, Dylan G. Suarez, Satoshi Mizuguchi, William Guy Hornsby, Aaron J. Cunanan, Donald J. Marsh, Michael H. Stone

ETSU Faculty Works

The purpose of this study was to investigate the kinetic and morphological adaptations that occur during distinct phases of a block periodized training cycle in weightlifters. Athlete monitoring data from nine experienced collegiate weightlifters was used. Isometric mid-thigh pull (IMTP) and ultrasonography (US) results were compared to examine the effects of three specific phases of a training cycle leading up to a competition. During the high volume strength-endurance phase (SE) small depressions in rate of force development (RFD) but statistically significant (p ≤ 0.05) increases in vastus lateralis cross-sectional area (CSA), and body mass (BM) were observed. The lower volume …

Tutorial For Using Sliceomatic To Calculate Thigh Area And Composition From Computed Tomography Images From Older Adults, Richard A. Dennis, Douglas E. Long, Reid D. Landes, Kalpana P. Padala, Prasad R. Padala, Kimberly K. Garner, James N. Wise, Charlotte A. Peterson, Dennis H. Sullivan

Center for Muscle Biology Faculty Publications

Objective

Area of muscle, fat, and bone is often measured in thigh CT scans when tissue composition is a key outcome. SliceOmatic software is commonly referenced for such analysis but published methods may be insufficient for new users. Thus, a quick start guide to calculating thigh composition using SliceOmatic has been developed.

Methods

CT images of the thigh were collected from older (69 ± 4 yrs, N = 24) adults before and after 12-weeks of resistance training. SliceOmatic was used to segment images into seven density regions encompassing fat, muscle, and bone from -190 to +2000 Hounsfield Units [HU]. The …

Functional And Skeletal Muscle Impairments In Progressive Diabetic Ckd, Daniel Bittel

Arts & Sciences Electronic Theses and Dissertations

1-in-3 persons with type 2 diabetes (T2DM) develop chronic kidney disease (CKD), which is characterized by progressive renal dysfunction leading to end-stage renal disease. In response to elevated blood glucose and systemic inflammation of diabetes, a process of active thickening of the renal glomerular basement membrane ensues with concomitant damage to the structural supports (podocytes) of the kidneyճ filtration barrier. This results in impaired renal filtration. The metabolic sequelea of T2DM and CKD also, synergistically, alter skeletal muscleճ degradative pathways, satellite cell function (muscle reparative cells), and mitochondrial health (muscle energetic machinery) -- resulting in muscle breakdown, poor muscle quality, …

Insights Into The Therapeutic Potential Of Salt Inducible Kinase 1: A Novel Mechanism Of Metabolic Control, Randi Fitzgibbon

Dissertations & Theses (Open Access)

Salt inducible kinase 1 (SIK1) has been considered a stress-inducible kinase since it was first cloned in 1999. Continued efforts since this time have been dedicated to characterizing the structure and function of SIK1. Such research has laid the ground work for our understanding of SIK1 action and regulation in tissue and stimuli dependent manners. The fundamental findings of this dissertation continue in this tradition and include investigations of SIK1 regulatory mechanisms in skeletal muscle cells, the cellular and physiological effects of SIK1 loss of function in vitro and in vivo, and intracellular metabolic and mitochondrial regulation by this …

Enhancement Of Aging Rat Laryngeal Muscles With Endogenous Growth Factor Treatment, Joseph C. Stemple, Richard D. Andreatta, Tanya S. Seward, Vrushali Angadi, Maria Dietrich, Colleen A. Mcmullen

Physical Therapy Faculty Publications

Clinical evidence suggests that laryngeal muscle dysfunction is associated with human aging. Studies in animal models have reported morphological changes consistent with denervation in laryngeal muscles with age. Life‐long laryngeal muscle activity relies on cytoskeletal integrity and nerve–muscle communication at the neuromuscular junction (NMJ). It is thought that neurotrophins enhance neuromuscular transmission by increasing neurotransmitter release. We hypothesized that treatment with neurotrophin 4 (NTF4) would modify the morphology and functional innervation of aging rat laryngeal muscles. Fifty‐six Fischer 344xBrown Norway rats (6‐ and 30‐mo age groups) were used to evaluate to determine if NTF4, given systemically (n = 32) …

The Effects Of Two Different Resistance Training Protocols With Similar Volume On Muscular Strength, Muscle Thickness, And Fat-Free Mass, Cory Worthey

Theses and Dissertations

The manipulation of exercise volume, intensity, and order is associated with producing different musculoskeletal changes. These resistance training program variables affect mechanical tension and metabolic stress associated with resistance training, therefore affecting strength and hypertrophic outcomes. PURPOSE: The purpose of this study was to examine the effects of two different volume-equated total body exercise protocols over 9 weeks using compound exercises on muscular strength, muscle thickness, and fat-free mass. METHODS: Eight well-trained men were randomly assigned to a hypertrophy-style protocol (HG) performing 3 sets of 10 repetitions with 90 seconds rest between sets (n = 4) or a strength-style protocol …

Lifestyle Contributors To Cardiovascular Disease Risk, Adam J. Berrones

Theses and Dissertations--Kinesiology and Health Promotion

Aortic stiffness is an independent risk factor that has prognostic value regarding future cardiovascular disease (CVD) events such as myocardial infarction, strokes, and heart failure. Although death rates due to coronary heart disease have declined in recent years, the leading global killer remains CVD and prevalence is still high. Understanding lifestyle contributors associated with aortic stiffness would provide the public with insight into targeting key health-related behaviors.

The purpose of this observational study was to examine the association of physical activity, physical function, and dietary quality as independent factors contributing to aortic stiffness in apparently healthy middle aged men. Fifty-two …

The Development Of Skeletal Muscle In Young Horses: An Ultrasonography And Satellite Cell Approach, Emma K. Lavigne

Honors Scholar Theses

Muscle growth in young horses is characterized by an increase in muscle cross-sectional area, which can be accomplished through the activation and differentiation of satellite cells. Satellite cells can be stimulated or inhibited in response to different cytokines and growth factors and are key mediators of muscle hypertrophy and regeneration. The aim of this study was to investigate the growth of the longissimus dorsi (LD) muscle in horses under 5 years of age and to obtain preliminary data on satellite cell behavior in foals. The area, width, height, and subcutaneous fat were measured using ultrasonography at 6-month increments over the …

Bracing Of The Trunk And Neck Has A Differential Effect On Head Control During Gait, S. Morrison, D. M. Russell, K. Kelleran, M. L. Walker

Rehabilitation Sciences Faculty Publications

During gait, the trunk and neck are believed to play an important role in dissipating the transmission of forces from the ground to the head. This attenuation process is important to ensure head control is maintained. The aim of the present study was to assess the impact of externally restricting the motion of the trunk and/or neck segments on acceleration patterns of the upper body and head and related trunk muscle activity. Twelve healthy adults performed three walking trials on a flat, straight 65-m walkway, under four different bracing conditions: 1) control-no brace; 2) neck-braced; 3) trunk-braced; and 4) neck-trunk …

Insulin Resistance And Muscle Insulin Receptor Substrate-1 Serine Hyperphosphorylation, Charles A. Stuart, Mary E. A. Howell, Brian M. Cartwright, Melanie P. Mccurry, Michelle L. Lee, Michael W. Ramsey, Michael H. Stone

ETSU Faculty Works

Insulin resistance in metabolic syndrome subjects is profound in spite of muscle insulin receptor and insulin-responsive glucose transporter (GLUT4) expression being nearly normal. Insulin receptor tyrosine kinase phosphorylation of insulin receptor substrate-1 (IRS-1) at Tyr896 is a necessary step in insulin stimulation of translocation of GLUT4 to the cell surface. Serine phosphorylation of IRS-1 by some kinases diminishes insulin action in mice. We evaluated the phosphorylation status of muscle IRS-1 in 33 subjects with the metabolic syndrome and seventeen lean controls. Each underwent euglycemic insulin clamps and a thigh muscle biopsy before and after 8 weeks of either strength or …