Medicine and Health Sciences Commons^™

Regulation Of Skeletal Muscle Plasticity By The Gut Microbiome, Taylor R. Valentino

Theses and Dissertations--Physiology

Recent evidence suggests that the gut microbiome could play a role in skeletal muscle plasticity, providing novel treatments for muscle wasting diseases and/or performance enhancements. I first sought to determine if the gut microbiome is necessary for skeletal muscle adaptation to exercise. Forty-two, four-month old, female C57Bl/6J underwent nine weeks of weighted wheel running or remained in cage with a locked wheel, without or without the administration of antibiotics (treated). In response to wheel running, I found that antibiotic depletion of the microbiome led to a blunted hypertrophic response in the soleus muscle as measured by normalized muscle wet weight …

Novel Mammalian Models For Understanding And Treating Spinal Cord Injury, Michael B. Orr

Theses and Dissertations--Physiology

Spinal cord injury (SCI) is devastating and often leaves the injured individual with persistent dysfunction. The injury persists because humans have poor wound repair and there are no pharmacologic treatments to induce wound repair after SCI. The continued efforts to discover therapeutic targets and develop treatments heavily relies on animal models. The purpose of this project is to develop and study novel mammalian models of SCI to provide insights for the development and effective implementation of SCI therapies.

Lab mice (Mus musculus) are a powerful tool for recapitulating the progression and persistent damage evident in human SCI, but …

The Mechanical Properties Of Non-Failing And Failing Human Myocardium, Cheavar A. Blair

Theses and Dissertations--Physiology

Heart failure is a clinical syndrome that manifests when there are structural and functional impairments to the heart that reduces the ability of the ventricles to fill or eject blood. The syndrome affects ~6 million Americans and is responsible for nearly 300,000 deaths annually. At the core of the syndrome are dysfunctional sarcomeres, the machinery that drives cardiac contraction and relaxation. By assessing the mechanical properties of human cardiac tissue, the information provided in this dissertation will provide data that demonstrates how sarcomeric dysfunction contributes to heart failure in the left and right ventricles. Additionally, these data will supply information …

The Effects Of Perinatal Oxycodone Exposure On The Stress Axis And Neurobehavior, Thitinart Sithisarn

Theses and Dissertations--Physiology

Opiate addiction is now a major public health problem. Pregnant women continue to use opiates during gestation; up to 5.4% of pregnant women report using illicit drugs during pregnancy. Previous studies have shown that perinatal insults and exposure to opiates such as morphine in utero can affect the development of the hypothalamic-pituitary-adrenal (HPA)-axis of the offspring and are associated with higher risk of developing neurobehavioral problems. Oxycodone, a semisynthetic putative kappa opioid receptor and partial mu opioid receptor agonist is now one of the most frequently abused pain killers during pregnancy, however limited data are available regarding whether and how …

Ppap2b Expression Limits Lesion Formation In Murine Models Of Atherosclerosis, Paul A. Mueller

Theses and Dissertations--Physiology

Coronary artery disease (CAD) is the leading cause of death in both men and women worldwide and is defined as a narrowing of the coronary arteries due to accumulation of atherosclerotic plaques. Genome-wide association studies have identified risk loci within the gene PPAP2B that confers increased risk of developing CAD. Evidence suggests these aforementioned SNPs are regulating PPAP2B expression in a cis-manner through the interruption of transcription factor binding sites. PPAP2B encodes the lipid phosphate phosphatase 3 enzyme that plays a key role in degrading bioactive lysophosphatidic acid (LPA). LPA has a plethora of effects on vascular tissue and is …

Development And Application Of Gadolinium Free Cardiac Magnetic Resonance Fibrosis Imaging For Multiscale Study Of Heart Failure In Patients With End Stage Renal Disease, Tori A. Stromp

Theses and Dissertations--Physiology

Cardiac magnetic resonance (CMR) is a powerful tool to noninvasively image ventricular fibrosis. Late gadolinium enhancement (LGE) CMR identifies focal and, with T1 mapping, diffuse fibrosis. Despite prevalent cardiac fibrosis and heart failure, patients with end stage renal disease (ESRD) are excluded from LGE. Absence of a suitable diagnostic has limited the understanding of heart failure and obstructed development of therapies in the setting of ESRD. A quantitative, gadolinium free fibrosis detection method could overcome this critical barrier, propelling the advancement of diagnostic, monitoring, and therapy options. This project describes the development of a gadolinium free CMR technique and application …

Transmural Heterogeneity Of Cellular Level Cardiac Contractile Properties In Aging And Heart Failure, Premi Haynes

Theses and Dissertations--Physiology

The left ventricle of the heart relaxes when it fills with blood and contracts to eject blood into circulation to meet the body’s metabolic demands. Dysfunction in either relaxation or contraction of the left ventricle can lead to heart failure. Transmural heterogeneity is thought to contribute to normal ventricular wall motion but it is not well understood how transmural modifications affect the failing left ventricle. The overall hypothesis of this dissertation is that normal left ventricles exhibit transmural heterogeneity in cellular level contractile properties and with aging and heart failure there are region-specific changes in cellular level contractile mechanisms.

Age …

Nmda Receptors In The Dorsal Vagal Complex Of Normal And Diabetic Mice, Eva C. Bach

Theses and Dissertations--Physiology

The dorsal vagal complex (DVC), containing the nucleus of the solitary tract (NTS) and the dorsal motor nucleus of the vagus nerve (DMV), plays a pivotal role in autonomic regulation. Afferent fibers from peripheral organs and higher brain centers synapse in the NTS, which integrates these synaptic connections as well as information from systemically circulating hormones and metabolites. The integrated information is relayed to the dorsal motor nucleus of the vagus nerve (DMV), which in turn, projects motor fibers to elicit parasympathetic control of digestive and other viscera. Physiological functions mediated by the DVC are disrupted in diabetic patients and …