Physiology Commons^™

Fatty Acid Fate In Determining Oxidation And Inflammation In Adipose Tissue, Emilio Patrick Mottillo

Wayne State University Dissertations

Adipose tissue (AT) is a critical regulator of energy balance through its ability to store or oxidize free fatty acids (FFAs). White adipose tissue (WAT) functions as an anabolic organ to sequester and release FAs, in contrast brown adipose tissue (BAT) is a catabolic organ that oxidizes FAs. However, a comprehensive understanding of the role that FFAs play in the function of WAT and BAT is needed. Here we demonstrate that intracellular FAs enhance the expression of inflammatory cytokines by β3-AR activation in adipocytes, in which the expression of PAI-1 is partly mediated by the de novo synthesis of ceramides/sphingolipids. …

Linking Environmental Toxicant Exposure To Diabetes Susceptibility, Jannifer Beth Tyrrell

Wayne State University Dissertations

An important and unresolved question in the environmental health field is whether exposure to common environmental toxicants, such as dioxin and heavy metals like Pb, increase the risk of developing diabetes, especially in combination with other common metabolic stressors such as obesity.

Previous studies suggested that dioxin exposure increased peripheral insulin resistance but did not appear to cause fasting hyperglycemia or elevated hepatic glucose output. In concordance with those findings we observed that dioxin treatment caused a strong suppression of the expression of the key hepatic gluconeogenic genes PEPCK and G6Pase. However, this suppression was not solely mediated by the …

Androgen Receptor-Target Genes In African American Prostate Cancer Disparities, Bi-Dar Wang, Qi Yang, Kristin Ceniccola, Fernando Bianco, Ramez Andrawis, Thomas W. Jarrett, Harold A. Frazier, Steven R. Patierno, Norman H. Lee

Pharmacology and Physiology Faculty Publications

The incidence and mortality rates of prostate cancer (PCa) are higher in African American (AA) compared to Caucasian American (CA) men. To elucidate the molecular mechanisms underlying PCa disparities, we employed an integrative approach combining gene expression profiling and pathway and promoter analyses to investigate differential transcriptomes and deregulated signaling pathways in AA versus CA cancers. A comparison of AA and CA PCa specimens identified 1,188 differentially expressed genes. Interestingly, these transcriptional differences were overrepresented in signaling pathways that converged on the androgen receptor (AR), suggesting that the AR may be a unifying oncogenic theme in AA PCa. Gene promoter …

Systems Biology In Animal Breeding: Identifying Relationships Among Markers, Genes, And Phenotypes [Breeding And Genetics Symposium], John B. Cole, Ronald M. Lewis, C. Maltecca, S. Newman, K. M. Olson, R. G. Tait

Department of Animal Science: Faculty Publications

The Breeding and Genetics Symposium titled “Systems Biology in Animal Breeding: Identifying relationships among markers, genes, and phenotypes” was held at the Joint Annual Meeting of the American Society of Animal Science and the American Dairy Science Association in Phoenix, Arizona, July 15-19, 2012. The primary goal of the symposium was to demonstrate the use of high-density SNP genotypes to determine the complex regulatory relationships among genotypes and phenotypes but also to present methods for studying complex relationships among phenotypes. Case studies from mammalian and avian species were included to emphasize the broad applicability of these methods.

The Role Of Macrophages In Exercise And Insulin Resistance In Human Skeletal Muscle, Jason S. Groshong

Theses and Dissertations--Physiology

Muscle biopsies were taken at baseline, post eccentric exercise, post aerobic training, and after training followed by eccentric exercise from adults with different health status. In Cell Western analysis of pAkt/Akt ratio suggests that muscle cells isolated from baseline biopsies respond to insulin in a dose dependent manner that tracks with sensitivity to insulin of the host; however, this is uncoupled from glucose disposal in vitro. Nitrotyrosine (NY), a marker of free radical damage, was employed to assess the efficacy of the exercise paradigm. NY immunohistochemistry on muscle cross-sections revealed that eccentric exercise significantly increased damage in older ( …

Euryhalinity In An Evolutionary Context, Eric T. Schultz, Stephen D. Mccormick

EEB Articles

This chapter focuses on the evolutionary importance and taxonomic distribution of euryhalinity. Euryhalinity refers to broad halotolerance and broad halohabitat distribution. Salinity exposure experiments have demonstrated that species vary tenfold in their range of tolerable salinity levels, primarily because of differences in upper limits. Halotolerance breadth varies with the species’ evolutionary history, as represented by its ordinal classification, and with the species’ halohabitat. Freshwater and seawater species tolerate brackish water; their empirically-determined fundamental haloniche is broader than their realized haloniche, as revealed by the halohabitats they occupy. With respect to halohabitat distribution, a minority of species (<10%) are euryhaline. Habitat-euryhalinity is prevalent among basal actinopterygian fishes, is largely absent from orders arising from intermediate nodes, and reappears in the most derived taxa. There is pronounced family-level variability in the tendency to be halohabitat-euryhaline, which may have arisen during a burst of diversification following the Cretaceous-Palaeogene extinction. Low prevalence notwithstanding, euryhaline species are potent sources of evolutionary diversity. Euryhalinity is regarded as a key innovation trait whose evolution enables exploitation of new adaptive zone, triggering cladogenesis. We review phylogenetically-informed studies that demonstrate freshwater species diversifying from euryhaline ancestors through processes such as landlocking. These studies indicate that some euryhaline taxa are particularly susceptible to changes in halohabitat and subsequent diversification, and some geographic regions have been hotspots for transitions to freshwater. Comparative studies on mechanisms among multiple taxa and at multiple levels of biological integration are needed to clarify evolutionary pathways to, and from, euryhalinity.

Effects Of Thermal Acclimation On The Critical Thermal Maxima Of The Tropical Cockroaches: Blaptica Dubia, Eublaberus Posticus And Blaberus Discoidalis (Blaberidae), Lauren Michelle Goode

Online Theses and Dissertations

The Critical Thermal Maxima (CTMax) is a measure of upper thermal tolerance. The physiological response upon reaching CTMax is similar across taxa, making CTMax useful in comparative studies. The CTMax defines the ecological lethal temperature of an organism and has been used to predict the effects of global climate change. CTMax was determined for adults and first instar nymphs of three species of tropical cockroaches: Blaptica dubia, Eublaberus posticus, and Blaberus discoidalis. Adult cockroaches were acclimated to temperatures of 10°C, 15°C, 20°C, 25°C, 31°C and 37°C for a period of seven days. Blaptica dubia was the only species to survive …

Blood Glucose Responses To Type, Intensity, Duration, And Timing Of Exercise, Sheri R. Colberg, Manuel J. Hernandez, Fatima Shahzad

Human Movement Studies & Special Education Faculty Publications

[First Paragraph] The Big Blue Test (BBT) is an annual initiative by the Diabetes Hands Foundation to raise awareness of the importance of physical activity in managing diabetes. Individuals with diabetes voluntarily exercise and record self-monitored blood glucose levels. During the 2012 BBT, 5,157 diabetic participants (~90% insulin users) anonymously entered exercise type, intensity, duration, time elapsed since last meal, and blood glucose readings before and after one or more bouts of exercise separately through www.BigBlueTest.org or an Iphone app.

Development And Validation Of A Predictive Model Of Acute Glucose Response To Exercise In Individuals With Type 2 Diabetes, Bryan S. Gibson, Sheri R. Colberg, Paul Poirier, Denise Maria Martins Vancea, Jason Jones, Robin Marcus

Human Movement Studies & Special Education Faculty Publications

Background: Our purpose was to develop and test a predictive model of the acute glucose response to exercise in individuals with type 2 diabetes.

Design and methods: Data from three previous exercise studies (56 subjects, 488 exercise sessions) were combined and used as a development dataset. A mixed-effects Least Absolute Shrinkage Selection Operator (LASSO) was used to select predictors among 12 potential predictors. Tests of the relative importance of each predictor were conducted using the Lindemann Merenda and Gold (LMG) algorithm. Model structure was tested using likelihood ratio tests. Model accuracy in the development dataset was assessed by leave-one-out cross-validation. …

Functional Effects Of Kcnq K(+) Channels In Airway Smooth Muscle, Alexey I. Evseev, Iurii Semenov, Crystal R. Archer, Jorge L. Medina, Peter H. Dube, Mark S. Shapiro, Robert Brenner

Bioelectrics Publications

KCNQ (Kv7) channels underlie a voltage-gated K+ current best known for control of neuronal excitability, and its inhibition by Gq/11-coupled, muscarinic signaling. Studies have indicated expression of KCNQ channels in airway smooth muscle (ASM), a tissue that is predominantly regulated by muscarinic receptor signaling. Therefore, we investigated the function of KCNQ channels in rodent ASM and their interplay with Gq/11-coupled M3 muscarinic receptors. Perforated-patch clamp of dissociated ASM cells detected a K+ current inhibited by the KCNQ antagonist, XE991, and augmented by the specific agonist, flupirtine. KCNQ channels begin to activate at voltages near resting potentials for ASM cells, and …

The Effects Of Hydrostatic Pressure On Early Endothelial Tubulogenic Processes, Ryan M. Underwood

Theses and Dissertations--Biomedical Engineering

The effects of mechanical forces on endothelial cell function and behavior are well documented, but have not been fully characterized. Specifically, fluid pressure has been shown to elicit physical and chemical responses known to be involved in the initiation and progression of endothelial cell-mediated vascularization. Central to the process of vascularization is the formation of tube-like structures. This process—tubulogenesis—is essential to both the physiological and pathological growth of tissues. Given the known effects of pressure on endothelial cells and its ubiquitous presence in the vasculature, we investigated pressure as a magnitude-dependent parameter for the regulation of endothelial tubulogenic activity. To …

Population Genetics And Ecology Of Regional Malaria Vectors In Amazonian Brazil, Sascha Naomi Mckeon

Legacy Theses & Dissertations (2009 - 2024)

Species complexes are common among anopheline mosquitoes, but only some members of complexes are disease vectors. Research involving overall patterns of divergence, phylogenetic relationships and population structure is partly driven by the operational need to be able to reliably distinguish component taxa that may be involved in malaria transmission. Anopheles triannulatus, An. nuneztovari and An. albitarsis are broadly distributed species complexes that contain local and regionally important malaria vectors, whose genetic diversity has been largely overshadowed by studies involving An. darlingi, the principal vector of Central and South America. I have analyzed the ecological suitability of habitats and geographical ranges …

Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya

Legacy Theses & Dissertations (2009 - 2024)

The Quechua populations have inhabited the Andes for hundreds of generations. The ability to thrive in this hostile environment, leading an active and healthy life has generated research questions about the special phenotype of Andean highlanders compared to their sea-level counterparts, such as their higher pulmonary volumes and their outstanding work capacity in spite of the challenge of oxygen transport and delivery in hypoxia. In high altitude natives, there have been two main explanations for the origins of the aforementioned traits: genetic adaptation through natural selection and developmental adaptation through the exposure to hypoxia during growth.

Seawater Flow Into The Digestive System Of Actinotroch Larvae (Phoronida), William Jaeckle

Scholarship

Actinotroch larva (Phoronida) concentrate and collect food particles during their planktonic existance. Reported mechanisms of particle capture include both ciliary reversal and direct interception along the larval tentacles, and suction of particle-containing seawater into the larval vestibule. These diverse mechanisms explain collection of particles, but not subsequent ingestion. Particle delivery into the digestive system is accomplished, at least in part, by the activity of the esophageal cilia. If and how the beat frequency of esophageal cilia is modified by the presence or absence of particulate or dissolved organic materials remains unknown for actinotroch larvae.

Physiological Muscle Qualitative Changes In Response To Resistance Training In Older Adults, Tyler Scanlon

Electronic Theses and Dissertations

Muscle function is determined by structure and morphology at the architectural level. In response to resistance training, older adults have demonstrated that the neuromuscular system has a substantial adaptability, which may compensate for muscle size and quality and lead to improved functional capacities and higher quality of life. PURPOSE: The purpose of this study was to examine the effect of six weeks of progressive resistance exercise on muscle morphology and architecture in healthy older adults. METHODS: Twenty- five healthy men and women were randomly assigned to either six weeks of progressive resistance training (RT) (n=13; age = 71.08 ± 6.75, …

The Effects Of 6-Weeks Of Resistance Training On The Neuromuscular Fatigue Threshold In Older Adults, Nadia Emerson

Electronic Theses and Dissertations

Age-related deficits in muscle mass, strength, and function place an increased burden of work on existing skeletal muscle and may lead to early onset of neuromuscular fatigue (NMF) during activities of daily living. Resistance exercise (RE) is the proven method for improving neuromuscular function in healthy older adults. PURPOSE: To investigate the effects of 6 weeks of RE on the NMF threshold as well as strength and functional performance in older adults. METHODS: Twenty-four older adults were randomly assigned to 6 weeks of RE (EXE; n = 12; age 72 ± 6.3 y; BMI 28.4 kg/m2 ) or control (CONT; …

Noninvasive Near-Infrared Diffuse Optical Monitoring Of Cerebral Hemodynamics And Autoregulation, Ran Cheng

Theses and Dissertations--Biomedical Engineering

Many cerebral diseases are associated with abnormal cerebral hemodynamics and impaired cerebral autoregulation (CA). CA is a mechanism to maintain cerebral blood flow (CBF) stable when mean arterial pressure (MAP) fluctuates. Evaluating these abnormalities requires direct measurements of cerebral hemodynamics and MAP. Several near-infrared diffuse optical instruments have been developed in our laboratory for hemodynamic measurements including near-infrared spectroscopy (NIRS), diffuse correlation spectroscopy (DCS), hybrid NIRS/DCS, and dual-wavelength DCS flow-oximeter. We utilized these noninvasive technologies to quantify CBF and cerebral oxygenation in different populations under different physiological conditions/manipulations. A commercial finger plethysmograph was used to continuously monitor MAP. For investigating …

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 …

Diet-Induced Obesity: Dopaminergic And Behavioral Mechanisms As Outcomes And Predictors, Vidya Narayanaswami

Theses and Dissertations--Pharmacy

Obesity and drug abuse share common neural circuitries including the mesocoticolimbic and striatal dopamine reward system. In the current study, a rat model of diet-induced obesity (DIO) was used to determine striatal dopamine function, impulsivity and motivation as neurobehavioral outcomes and predictors of obesity. For the outcome study, rats were randomly assigned a high-fat (HF) or a low-fat (LF) diet for 8 wk. Following the 8-wk HF-diet exposure, rats were segregated into obesity-prone and obesity-resistant groups based on maximum and minimum body weight gain, respectively, and neurobehavioral outcomes were evaluated. For the predictor study, neurobehavioral antecedents were evaluated prior to …

The Big Blue Test: Effects Of 14 Minutes Of Physical Activity On Blood Glucose Levels, Sheri R. Colberg, Manuel J. Hernandez

Human Movement Studies & Special Education Faculty Publications

[First paragraph] For most with diabetes, physical activity has a blood glucose lowering effect (1). Hypoglycemia (i.e., blood glucose < 65 mg/dL) resulting from exercise is a concern, particularly for insulin users (2).