Musculoskeletal, Neural, and Ocular Physiology Commons^™

Expanding The Role Of Muscle Stem Cell Fusion In Muscle Under Hypertrophic Stimulus, Jensen Goh Zhong Sheng

Theses and Dissertations--Physiology

Muscle stem cells (MuSCs) are a unique stem cell population that can activate in response to both injury and growth stimuli. Studies on muscle regeneration have shown MuSC activation follows a uniform progression through proliferation, differentiation, and fusion. Therefore, to determine whether MuSC replication is a prerequisite for differentiation under hypertrophic stimulus, I used a lineage-tracking mouse model (Pax7^rtTA; TRE-H2B-GFP) to label MuSC nuclei and simultaneously tracked DNA synthesis via EdU incorporation. This dual-labeling approach allowed us to not only distinguish MuSC-derived nuclei but also demarcate which MuSC had proliferated prior to fusion. I then employed a mechanical …

Ovarian Cancer G Protein-Coupled Receptor-1 Signaling Bias Dictates Anti-Contractile Effect Of Benzodiazepines On Airway Smooth Muscle, Dominic R. Villalba, Arun K. Jannu, Elham Javed, Isha Dandekar, Ruping Wang, Deepak A. Deshpande, Steven S. An, Reynold A. Panettieri, Dale D. Tang, Raymond B. Penn, Ajay P. Nayak

Center for Translational Medicine Faculty Papers

BACKGROUND: We recently reported that the ovarian cancer G protein-coupled receptor-1 (OGR1) can be pharmacologically biased with specific benzodiazepines to couple with distinct heterotrimeric G proteins in human airway smooth muscle (ASM) cells. Lorazepam stimulated both G

METHODS: Models of histamine (His) -stimulated contraction included imaging of ex vivo human precision cut lung slices (hPCLS) and Magnetic Twisting Cytometry (MTC) analysis of human ASM cell stiffness. To explore mechanisms of regulation, we examined effects on myosin light chain (pMLC) phosphorylation and PKA activity in primary human ASM cultures, as well as actin cytoskeleton integrity as defined by changes in the …

Ibuprofen, Flurbiprofen Or Naproxen Sodium Minimally Influences Musculoskeletal Adaptations To Treadmill Exercise In Rats, Brandon Roberts, Alyssa Geddis, Alexandra Ciuciu, Marinaliz Reynoso, Nikhil Mehta, Alyssa Varanoske, Alyssa Kelley, Maximus Leiss, Alexander Kolb, Julie Hughes, Marshall Naimo, Ryan Tomlinson, Jeffery Staab

Department of Orthopaedic Surgery Faculty Papers

BACKGROUND: Non-steroidal anti-inflammatory drugs (NSAIDs) may influence musculoskeletal health. The purpose of this study was to compare the effects of three different NSAIDS: naproxen sodium, ibuprofen, flurbiprofen or a placebo on musculoskeletal adaptations in rodents with or without 6 weeks of aerobic exercise.

METHODS: Nine-week-old male Wistar rats (n = 80) were randomized to either exercise (EX) or no-exercise control (CON) conditions and treated with naproxen, ibuprofen (IBU), flurbiprofen (FLU) or placebo (PLA). For exercise, rats ran 5 days per week for 6 weeks at a 5% incline on a motorized treadmill for 30 min. Three-point bending (3 PB) and …

Mammalian And Invertebrate Models As Complementary Tools For Gaining Mechanistic Insight On Muscle Responses To Spaceflight, Amber M. Paul, Thomas Cahill, Henry Cope, Joseph J. Bass, Eliah G. Overbey, Rachel Gilbert

Publications

Bioinformatics approaches have proven useful in understanding biological responses to spaceflight. Spaceflight experiments remain resource intensive and rare. One outstanding issue is how to maximize scientific output from a limited number of omics datasets from traditional animal models including nematodes, fruit fly, and rodents. The utility of omics data from invertebrate models in anticipating mammalian responses to spaceflight has not been fully explored. Hence, we performed comparative analyses of transcriptomes of soleus and extensor digitorum longus (EDL) in mice that underwent 37 days of spaceflight. Results indicate shared stress responses and altered circadian rhythm. EDL showed more robust growth signals …

Osteocyte Activity And Skeletal Muscle Relative Gene Expression Profiling After Short-Term Muscle Paralysis, Michelle Gelbs

Dissertations and Theses

Mechanical loading is essential for maintaining bone tissue. Reduced mechanical loading has been shown to have a negative effect on bone, and can result in the development of disuse osteoporosis. Disuse models of muscle inactivity and immobilization, like the Botox model used in this study, result in changes in the bone microarchitecture, the mechanisms behind which are not fully understood. In a previous four-week Botox disuse study, skeletally mature 20- week-old rats experienced degradation of intracortical bone, increased vascular porosity, and decreased osteocyte lacunar density in the tibiae. The focus of this study was to explicate a potential source of …

Mitochondrial Contributions To Disuse Atrophy: Let’S Talk About Sex, Megan Rosa-Caldwell

Graduate Theses and Dissertations

Skeletal muscle atrophy is a hallmark of many pathologies and is associated with disease prognosis, quality of life, and mortality. Specifically, lack of contractile activity of the muscle can result in disuse-associated atrophy. Disuse-induced atrophy is a common phenomenon in intensive care unit (ICU) patients and significantly impacts patient prognosis and ability to transition of out of intensive care. However, effective therapeutics to mitigate disuse-associated atrophy do not exist, clearly demonstrating the scientific and clinical need to further understand mechanisms contributing to disuse atrophy. In particular, a significant portion of the scientific literature has utilized male models, yet there is …

Impedance Changes In Biceps Brachii Due To Isometric Contractions And Muscle Fatigue Using Electrical Impedance Myography (Eim), Travis Orth

College of Graduate Studies: Theses & Dissertations

Electrical impedance myography (EIM) is a non-invasive technique used to evaluate neuromuscular conditions by using a quantitative parameter called impedance (Z). It relies upon the application and measurement of high-frequency, low-intensity electrical current imbedded over a localized muscle to determine its opposition to current flow. In brevity, impedance determines the resistance of muscle fibers due to changes in muscle composition. The objective of this thesis was to establish a relationship between muscles at rest and during isometric contractions at various force levels(25%, 50%, and 100% of maximum voluntary contraction) of the biceps brachii over a multifrequency spectrum. Impedance measurements due …

Effects Of Aging And Gender On Regulators Of Muscle Adaptation In F344/Bn Rat Model, Satyanarayana Paturi

Theses, Dissertations and Capstones

Sarcopenia is the loss of muscle mass and strength that occurs with aging. Here we examine the effects of aging and gender on the regulation of molecules believed to regulate muscle growth and adaptation in the F344/BN rat. In male animals, soleus and EDL muscle/body weight ratio declined continuously with aging while muscle atrophy in female animals plateaued at 26-months and remained constant thereafter. Aging increased the phosphorylation of protein kinase-B (Akt) and the mammalian target of rapamycin (mTOR) in the female but not male soleus muscle. This finding was associated with the attenuation of muscle atrophy observed in female …