Medicine and Health Sciences Commons^™

The Enzymatic Regulation Of Contraction-Induced Toll-Like Receptor 4 Shedding From C2c12 Myotubes, Rebekah C. Gridley

Health, Exercise, and Sports Sciences ETDs

Stimulated contractions are shown to increase toll-like receptor 4 (TLR4) release from C2C12 myotubes in vitro. The purpose of this study was to determine if the release of TLR4 from myotubes is controlled by proteolytic membrane cleavage. A broad-spectrum metalloprotease inhibitor was used to test this hypothesis in a C2C12 cell culture model, and TLR4 concentrations in the cell culture supernatant were measured via enzyme-linked immunosorbent assay (ELISA) following stimulated myotube contractions.

ELISA analysis revealed TLR4 concentrations below the sensitivity threshold of the ELISA kit for all experimental conditions. In confirming the effectiveness of the electrical pulse stimulation (EPS) treatment, …

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 …

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 …

Microvascular Stenosis In Critical Limb Ischemia: Role Of Partial Endothelial To Mesenchymal Transition, Jacqueline M. Chevalier

Electronic Thesis and Dissertation Repository

Critical limb ischemia (CLI) is a widespread and debilitating manifestation of atherosclerosis. Unfortunately, revascularization strategies are often precluded or unsuccessful, resulting in amputation. A major reason for treatment failure is likely co-existing abnormalities in ­­the microvasculature. However, the specific microvascular defects present in end-stage PAD in humans remain unknown.

The purpose of this study was to delineate abnormalities in the microvascular wall in the critically ischemic skeletal muscle of patients with CLI.

To elucidate the microvascular landscape in CLI, we studied human tibialis anterior and gastrocnemius muscles harvested from below-knee amputations of 10 individuals with CLI. Control muscles are from …

Characterization Of The Roles Of Muscle-Synthesized Brain-Derived Neurotrophic Factor And Presynaptic Tyrosine Receptor Kinase B In Motor Neuron Axonal Transport, Luke A. Vanosdol

All NMU Master's Theses

Brain-derived neurotrophic factor (BDNF) is a small, diffusible protein essential for the development and function of neurons. It is synthesized by many types of tissue, including muscle. BDNF actions are mediated via binding to its receptor, tyrosine receptor kinase B (TrkB). The BDNF-TrkB complex is endocytosed into a specialized vesicle, which induces downstream signaling cascades locally in the dendrites, or, more often, is delivered to the cell soma via retrograde axonal transport, where it modulates gene expression. BDNF activation of TrkB is critical for the initiation of axonal transport, and this cellular process relies on the interaction of numerous adaptor …

The Effect Of Insulin Treatment And Exercise Modality On Skeletal Muscle Fiber Size In Streptozotocin-Induced Type 1 Diabetic Rats, John Z. Nickels

Electronic Thesis and Dissertation Repository

Severe Type 1 Diabetes Mellitus (T1DM) is known to have several negative effects on skeletal muscle mass, a condition known as diabetic myopathy. One of these effects is the atrophy of the glycolytic muscle fibers. However, the role of intensity of insulin treatment and exercise modality in attenuating this loss in fiber cross-sectional area (CSA) specifically has yet to be determined. The purpose of this investigation was to determine the effects of 12 weeks of differing intensity of insulin therapy and exercise modality on the CSA of plantaris muscle fibers, identified by myosin heavy chain (MHC) of STZ-induced T1DM rats. …

The Roles Of Nuclear Receptor Nr4a1 In Cancer Cell Proliferation And Skeletal Muscle Differentiation, Alexa Farmer

Theses and Dissertations (ETD)

Nuclear receptors (NRs) constitute a major class of drug targets in the treatment of various cancer types. NRs respond to cellular signals and become activated upon ligand binding to transcriptionally modulate expression of target genes. NR4A1 (Nur77) is a member of the NR4A family of nuclear receptors and displays an oncogenic profile in many cancer models. It is often upregulated in adult solid malignancies and is known to promote cell proliferation and survival. Knockdown studies of NR4A1 in cancer cell lines results in decreased cell growth and angiogenesis and increased apoptosis, suggesting NR4A1 is an oncogenic protein. Due to the …

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 …

Invited Review: Heat Shock Proteins And Exercise: A Primer, Earl Noble, Kevin Milne, C.W. Melling

Jamie Melling

Heat shock proteins (HSPs) are, in general, prosurvival molecules within the cellular environment, and the overexpression of even just 1 family of HSPs can lead to protection against and improvements after a variety of stressors. Not surprisingly, a fertile area of study has grown out of effors to exploit the innate biologic behaviour of HSPs. Exercise, because of the inherent physiologic stresses associated with it, is but 1 stimulus that can result in a robust increase in various HSPs in several tissues, not the least of which happen to be the heart and skeletal muscle. The purpose of this review …