Medicine and Health Sciences Commons^™

Modeling The Effects Of Adverse Childhood Experiences Using A Mouse Model Of Neglect: Mechanisms Of Adiposity Expansion In Females, Jacqueline Leachman

Theses and Dissertations--Pharmacology and Nutritional Sciences

Adverse childhood experiences (ACEs) are an independent risk factor for chronic disease, including obesity and metabolic syndrome. We have previously shown that a mouse model of early life stress, maternal separation and early weaning (MSEW), exacerbates high-fat diet (HF)-induced obesity only in adult female mice. In agreement, the analysis of several cohorts of participants exposed to ACEs have shown that women are more susceptible to develop obesity than men. Therefore, the aim of this study was to investigate the link between early life stress and obesity in pre-clinical and clinical settings. Male and female MSEW mice fed 1 week a …

Deletion Of Period Genes Exacerbates Diet-Induced Obesity In Female, But Not Male, Mice, Elizabeth Kantra

Theses and Dissertations--Biology

Sex differences in obesity in mice are mediated by differential responses of circadian rhythms to high-fat feeding in males and females. Other studies also showed circadian Period genes regulate diet-induced obesity in mice. In this study, we investigated the role of the Period genes in regulating sex differences in obesity. Male and female C57BL/6J wild type, Per1/2 KO, and Per1/2/3 KO mice were housed in 12L:12D and fed high-fat diet for 12 weeks. We found a striking sex difference in obesity such that disabling the Period genes exacerbated adiposity in female, but not male, mice. Increased adiposity in female Period …

Factors Regulating Features Of Metabolic Syndrome, Sonja S. Pijut

Theses and Dissertations--Pharmacy

The collective presence of central obesity, low HDL-cholesterol, and elevated triglycerides, blood pressure, and fasting blood glucose constitutes Metabolic Syndrome (MetS), a disease state that increases the risk of cardiovascular disease (CVD) and Type 2 Diabetes Mellitus (T2DM). Nonalcoholic fatty liver disease (NAFLD), present in up to 90% of obese adults, is also linked to MetS. As in CVD, disruptions in cholesterol metabolism play a contributing role in the development of T2DM and NAFLD. Genes involved in cholesterol synthesis, secretion, and catabolism are diurnally regulated in the liver and adipose. Disruptions in the sleep-wake cycle are thought to potentiate metabolic …

An Investigation Of Perinatal Polychlorinated Biphenyl Exposure On Body Composition And Glucose Homeostasis, Cetewayo S. Rashid

Theses and Dissertations--Nutritional Sciences

Recent advancements have uncovered environmental contributions to obesity and diabetes etiology. In fact, perinatal malnutrition resulting in low birth weight (LBW) has been shown to correlate with later life obesity and impaired glucose tolerance in aged offspring. LBW can result from a myriad of developmental perturbations including macronutrient restriction, hypoxia, maternal stress and toxin exposure.

Polychlorinated biphenyls (PCBs) are ubiquitous environmental pollutants that bioaccumulate in the food chain resulting in dietary exposure in humans. Maternal and cord blood PCB levels are inversely associated with birth weight, and recent studies indicate that perinatal exposures to PCBs contribute to gender-specific obesity development …

Novel Insights Into The Function And Regulation Of Group X Secretory Phospholipase A2, Joseph D. Layne Jr

Theses and Dissertations--Nutritional Sciences

Group X secretory phospholipase A₂ (GX sPLA₂) hydrolyzes membrane phospholipids producing free fatty acids and lysophospholipids. Previous studies from our lab suggest that mice with targeted deletion of GX sPLA₂ (GX KO) have increased age-related weight gain due to an increase in overall adiposity. Paradoxically, this increased adiposity is associated with improved age-related glucose intolerance. GX KO mice also demonstrate a reduced inflammatory response to lipopolysaccharide injection. In vitro studies indicate this phenotype may be attributable to blunted macrophage mediated inflammatory responses. Given the role of macrophages in promoting adipose tissue (AT) inflammation and metabolic dysfunction …

Effects Of Adipocyte Deficiency Of Angiotensin Type 1a Receptors In Models Of Obesity And Hypercholesterolemia, Kelly Anne Putnam

Theses and Dissertations--Nutritional Sciences

Adipocytes express angiotensin II (AngII) receptors; however the direct effects of AngII at the adipocyte remain unclear. Knockout mouse models of renin-angiotensin system components exhibit reduced body weight, reduced adiposity, improved glucose tolerance, and improved blood pressure when fed high fat diets, which may be due to reduced action of AngII through the AT1aR in adipocytes. Additionally, hypercholesterolemic AT1aR deficient mice are protected from AngII-induced increases in atherosclerosis and abdominal aortic aneurysm (AAA) formation. We hypothesized that deficiency of AT1aR in adipocytes would reduce the development of obesity, obesity-induced disorders, and vascular diseases. To test this hypothesis, we created a …

Role Of Angiotensin Converting Enzyme 2 (Ace2) In Obesity-Associated Hypertension, Manisha Gupte

University of Kentucky Doctoral Dissertations

The purpose of this research was to determine whether adipocytes express ACE2 and its role in obesity-associated hypertension with diet-induced obesity.

To determine if ACE2 was expressed in adipose tissue and its regulation in the setting of diet-induced obesity, we fed male mice either a low fat (LF) or high fat (HF) diet acutely (1 week) or chronically ( 4 months). We demonstrated that ACE2 was regulated specifically in adipose tissue with consumption of a HF diet. However, with chronic HF feeding adipose ACE2 was dysregulated resulting in activation of the systemic RAS and increased blood pressure.

To determine the …

Neural Mechanisms Of Sympathetic Activation During Hyperinsulinemia And Obesity-Induced Hypertension, Megan Elyse Bardgett

University of Kentucky Doctoral Dissertations

Obesity afflicts more than 30% of the U.S. population and is a major risk factor for the development of hypertension, type II diabetes, and cardiovascular disease. Studies in humans and animals indicate that obesity is associated with increased sympathetic outflow to the vasculature and kidneys. One mechanism postulated to underlie the increase in sympathetic nerve activity (SNA) in obesity is hyperinsulinemia. Little is known regarding the central circuitry underlying elevated SNA and arterial blood pressure (ABP) during hyperinsulinemia and obesity or if sympathoexcitatory circuits are still responsive to insulin in obesity.

Hyperinsulinemic-euglycemic clamps elevate SNA to the hind limb vasculature …