The progesterone receptor membrane component 1 (PGRMC1) is a multifunctional protein with a heme-binding domain that promotes cellular signaling via receptor trafficking, and is essential for some elements of tumor growth and metastasis. PGRMC1 is upregulated in breast, colon, lung and thyroid tumors. We expanded the analysis of PGRMC1 in the clinical setting, and report the first analysis of PGRMC1 in human oral cavity and ovarian tumors and found PGRMC1 to correlate with lung and ovarian cancer patient survival. Furthermore, we discovered a specific role for PGRMC1 in cancer stem cell viability. PGRMC1 directly associates with the epidermal growth factor (EGFR) in cancer cells, and we reviewed multiple signaling-associated pathways that are important in trafficking wild-type and mutant EGFR. To better understand the potential of PGRMC1 in receptor tyrosine kinase trafficking, we extended our research to the insulin receptor (IR). Changes in insulin signaling have been linked to multiple diseases, because IR plays a key role in glucose metabolism, cellular survival and proliferation. We found PGRMC1 to co-precipitate with IR in cancer cells and in an adipose model system. PGRMC1 increased IR plasma membrane levels in multiple cancer cell lines, and was also found to increase plasma membrane levels of two glucose transporters. Treatment with a PGRMC1 ligand significantly increased IR levels in human adipocytes. Moreover, we demonstrate that both insulin binding and glucose uptake are dependent on PGRMC1.

Health inequalities take many forms related to race, gender, socioeconomic status, ethnic, language and many other axes throughout communities around the world. Type two diabetes, high blood pressure, and high cholesterol are examples of conditions (among many others) that disproportionately affect Latino@s in the U.S.. The research of this dissertation is based on fieldwork conducted throughout several predominantly Latin@ neighborhoods in Chicago, IL. This dissertation examines how Latin@s in Chicago navigate health and well-being, and how they engage in agentive strategies in the face of chronic disease. I recorded individual life histories and semi-structured interviews, focus groups, and participant observation at various community events and settings. The stories of these Chicago Latin@s are shared here in an effort to de-homogenize the depiction of Latin@s in the U.S. by paying attention to local narratives, and especially to those related to living with chronic disease.

Patients with liver disease have an increased risk for malnutrition because of side effects of the disease. The Nutrition Focused Physical Exam (NFPE) was developed for nutrition professionals to aid physicians in a nutrition-based diagnosis of malnutrition. The purpose of this study was to examine the NFPE for its validity in liver disease patients being evaluated for transplant. In addition, the NFPE was used to assess incidence and severity of malnutrition in end stage liver disease patients and compare these results to already developed malnutrition tools such as the Patient Generated-Subjective Global Assessment (PG-SGA), Triceps Skinfolds (TSF), Mid-Arm Circumference (MAC), Lumbar Index, and Total Psoas Muscle Area (TPA). The NFPE was found to be highly correlated with PG-SGA results. There was a weak correlation between the NFPE and the TSF, MAC, and Lumbar Index/TPA, except when comparing the bottom 25% quartile of the Lumbar Index to severe malnutrition using the NFPE. This resulted in a moderate correlation. The odds-ratio for hospital admission based on malnutrition and severe malnutrition were both extremely high (14.571, 18.857 respectively). These preliminary results reinforce the significance of the NFPE and the need for additional studies using this tool.

In horses, a painful and often debilitating disease known as laminitis can result in impaired function and, in severe cases, euthanasia. Equine Metabolic Syndrome (EMS) is a syndrome in horses that results in development of laminitis and is characterized by the presence of general and/or regional adiposity (“cresty neck”), aberrations in blood lipid concentrations, insulin resistance (IR) and/ or hyperinsulinemia. Therapies have focused on improving the state of obesity and insulin resistance with the goal of diminishing the likelihood of laminitis development. A definitive cause for laminitis has not been established, but hyperinsulinemia and IR are likely candidates as experimental states of hyperinsulinemia have been shown to induce laminitis and improvements in insulin sensitivity and obesity have been associated with a decreased risk of laminitis development. This dissertation discusses associations between obesity and IR, as well as potential therapies for alleviating insulin resistance with the ultimate goal of decreasing the risk of developing laminitis. Therapies evaluated included chromium and magnesium, levothyroxine sodium, and metformin hydrochloride. Horses were treated with each supplement for 10 to 36 weeks, depending on the supplement tested, and physical measurements such as body weight, neck circumference, and body condition score were obtained. Throughout each study, blood concentrations of glucose, insulin, and plasma lipids were analyzed. Chromium and magnesium currently do not appear to have any effect on insulin sensitivity, whereas results of levothyroxine administration indicate therapeutic responses, as does metformin, though results indicate further work are required. Research contained in this dissertation focuses on the potential of identifying animals at risk of developing IR and laminitis through measurement of blood biomarkers such as adiponectin and glucagon-like peptide 1. Assays to measure markers included enzyme-linked immunosorbent assays, western blots, and radioimmunoassays. Glucagon-like peptide 1 currently does not appear to differ between healthy and IR animals, but protein band density of high-molecular weight adiponectin does appear to be lower in horses with IR when compared to healthy animals. There is still much to learn about IR in horses, and therapy appears to be dependent on a case by case basis.

Diet-induced obesity promotes type 2 diabetes (T2D). Drugs that inhibit the renin-angiotensin system (RAS) have been demonstrated in clinical trials to decrease the onset of T2D. Previously, we demonstrated that mice made obese from chronic consumption of a high-fat (HF) diet have marked elevations in systemic concentrations of angiotensin II (AngII). Pancreatic islets have been reported to possess components of the renin-angiotensin system (RAS), including angiotensin type 1a receptors (AT1aR), the primary receptor for AngII, and angiotensin converting-enzyme 2 (ACE2), which negatively regulates the RAS by catabolizing AngII to angiotensin-(1-7) (Ang-(1-7)). These two opposing proteins have been implicated in the regulation of β-cell function. We hypothesized that the RAS contributes to the decline of β-cell function during the development of T2D with obesity. To test this hypothesis we first examined the effects of whole-body deficiency of ACE2 in mice on β-cell function in vivo and in vitro during the development of T2D. Whole-body deficiency of ACE2 resulted in impaired β-cell adaptation to insulin resistance with HF-feeding and a reduction of in vivo glucose-stimulated insulin secretion (GSIS) associated with reduced β- cell mass and proliferation. These results demonstrate that ACE2 plays a role in the adaptive response to hyperinsulinemia with obesity. In islets from HF-fed mice, AngII inhibited GSIS. In mice with pancreatic-specific deletion of AT1aR, AngII-induced inhibition of GSIS in vitro from islets of HF-fed mice was abolished. However, there was no effect of pancreatic AT1aR-deficiency on glucose homeostasis in vivo in HF-fed mice exhibiting pronounced hyperinsulinemia. Notably, pancreatic weight, insulin content and basal and glucose-stimulated insulin secretion from islets were decreased in mice with pancreatic AT1aR deficiency. These results suggest that AT1aR may contribute to pancreatic cell development, and also contribute to AngII-induced reductions in GSIS from islets of HF-fed mice. Overall, these studies suggest a role for the RAS in the regulation of β-cell function in T2D.

Angiotensinogen is the only known precursor in the renin-angiotensin system, a hormonal system best known as an essential regulator of blood pressure and fluid homeostasis. Angiotensinogen is sequentially cleaved by renin and angiotensin- converting enzyme to generate angiotensin II. As the major effector peptide, angiotensin II mainly function through angiotensin type 1 receptor. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and more recently renin inhibitors are widely known as the 3 classic renin-angiotensin system inhibitory drugs against hypertension and atherosclerosis. Here, we developed an array of regents to explore the effects of angiotensinogen inhibition. First, we demonstrated that genetic deficiency of angiotensinogen not only protected against hypercholesterolemia- induced atherosclerosis but also prevented diet-induced obesity. Then we found weekly intraperitoneal injection of antisense oligonucleotides against angiotensinogen remarkably surpressed body weight gain in mice fed a western diet, which was absent from classic renin-angiotensin system inhibition. The suppressed body weight gain was attributable to diminished body fat mass gain and enhanced energy expenditure. More excitingly, angiotensinogen antisense oligonucleotides regressed body weight gain on obese mice. Together, our findings revealed a unique feature of angiotensinogen inhibition beyond classic renin angiotensin inhibition and demonstrated therapeutic potentials of angiotensinogen antisense oligonucleotides against hypertension, atherosclerosis, and obesity. We also developed an in vivo system to explore the functional consequences of disrupting a conserved Cys18-Cys137 disulfide bridge in angiotensinogen. The formation of this disulfide bridge could trigger conformational changes in angiotensinogen, thereby facilitating renin cleavage of angiotensinogen. It was predicted that the redox-sensitive disulfide bridge might change the efficiency of angiotensinogen/renin reaction to release angiotensin II, thus modulate angiotensin II-dependent functions. We determined effects of the presence and absence of the disulfide bridge on angiotensin II concentrations and responses in mice expressing either native angiotensinogen or Cys18Ser, Cys137Ser mutated angiotensinogen in liver via adeno-associated viral vectors. Contrary to the prediction, disruption of Cys18-Cys137 disulfide bridge in angiotensinogen had no discernible effects on angiotensin II production and angiotensin II-dependent functions in mice.

Obesity is associated with insulin resistance, dyslipidemia, and cardiovascular disease. The current obesity epidemic is the result of surplus energy consumption. Excess energy is stored in expanding adipose tissue. Adipose tissue growth entails the enlargement of existing adipocytes, the formation of new fat cells from preexisting progenitors, and the coordinated development of supporting vasculature. Identifying adipocyte progenitors and the mechanism of adipose tissue expansion is crucial for the development of new strategies to combat obesity and its complications. Though important progress has been made towards understanding the developmental origin of adipocytes, the identities of adipocyte progenitors are still not completely known. The main objective of this study is to determine whether endothelial cells of the adipose tissue can give rise to new adipocytes. Our results indicate that murine endothelial cells of adipose tissue are pluripotent and can potentially give rise to preadipocytes. Lineage tracing experiments using the VE-Cadherin-Cre transgenic mouse reveal localization of reporter genes in endothelial cells, preadipocytes and white and brown adipocytes. Moreover, capillary sprouts from human adipose tissue, which have predominantly endothelial cell characteristics, are found to express Zfp423, a preadipocyte determination factor. In response to PPARγ activation, endothelial characteristics of sprouting cells are progressively lost, and cells form structurally and biochemically defined adipocytes. Taken together, our data support an endothelial origin of a population of adipocytes. The ability of the vascular endothelium to give rise to adipocytes may explain how angiogenesis and adipogenesis can be temporally and spatially coordinated. Analysis of BAT and WAT revealed that adipose depots have distinct compositions of adipocyte progenitors. Of the CD45-CD29+Sca1+CD24+ progenitor population, only 17% and 52% express VE-Cadherin in WAT and BAT, respectively. Our data show that the number of these specific progenitors in BAT and WAT are highly variable and suggest that a considerable number of adipocytes progenitors may have a non-endothelial cell origin. Differences in composition and types of adipocyte progenitors may explain the differences in the adipocytes phenotypes that we observe in discrete depots. In brief, we find that the vascular endothelium gives rise to a population of brown and white fat cells, and that the number of endothelial-derived adipocyte progenitors residing in BAT and WAT is highly variable. These results expand our current understanding of adipose tissue growth, and, we hope, will accelerate the development of treatments for obesity-related complications.

O presente trabalho teve por objetivo avaliar a microbiota subgingival pela técnica de Checkerboard e o perfil de citocinas por imunoensaio com princípio sanduíche baseado na tecnologia fluxometria do fluido gengival e soro em indivíduos não obesos; e em indivíduos com obesidade, antes e após cirurgia bariátrica. Diferenças na microbiota bucal foram observadas entre não obesos e obesos para 19 espécies bacterianas, particularmente E. corrodens que apresentou diferenças significativas em obesos, com consequente redução após a perda de peso. As citocinas IL-1b, IL-6, IL-10, IL-13, IL-17, TNF-a, leptina e adiponectina apresentaram diferenças estatisticamente significantes (p<0,05) quando esses indivíduos foram comparados. Todas as citocinas analisadas no soro diminuíram após a redução de peso, apenas a adiponectina apresentou concentrações significativamente mais elevadas (p<0,05). Assim, a obesidade promove alterações na microbiota subgengival e na resposta imunológica local e sua prevenção ou controle pode favorecer a saúde bucal. / In this study, the aimed to evaluate the subgingival microbiota using Checkerboard technique and the cytokines profile by using immunoassay based on the flowmetry gingival fluid and serum in non-obese and obese individuals, before and after bariatric surgery. Differences were observed in the oral microbiota between nonobese and obese for 19 bacterial species, particularly E. corrodens that showed significant differences in obese, with a consequent reduction after weight loss. The cytokines IL-1b, IL-6, IL-10, IL-13, IL-17, TNF-a, leptin and adiponectin were statistically different (p <0.05) when these individuals were compared. All analyzed cytokines in serum decreased after weight reduction only adiponectin concentrations showed significantly higher (p <0.05). Thus, obesity causes changes in the subgingival microbiota and the local immune response, and prevention and control can promote oral health.

Diabetes mellitus (DM) is a group of non-infectious diseases that cause hyperglycemia. DM symptoms were first clinically described by ancient Greek physicians whose prescriptions included plant-based remedies. Today, DM affects >400 million people globally and prevalence rates are rapidly increasing in developing countries where basic healthcare relies on local knowledge of botanical remedies. Many developing countries are home to diverse peoples and plants—providing fodder for varied plant-selection strategies and unique botanical pharmacopoeias. I addressed the plant-selection strategies used in a multi-ethnic, developing country, Trinidad and Tobago (T&T), to ascertain their role in shaping the local antidiabetic pharmacopoeia and to assess their benefits and risks in identifying safe and useful remedies. Using literature reviews, field surveys, and laboratory bioassays, I completed three categories of analysis. Ethnobotanical analyses showed that T&T’s antidiabetic pharmacopoeia is primarily of recent origin as >50% of the 48 historical DM remedies were Neotropical natives, including congenerics of well-known medicinal Paleotropical genera. Nevertheless, conservative knowledge transmission was also evident as several Paleotropical species of T&T’s pharmacopoeia, including Momordica charantia and Catharanthus roseus were also used in Africa, India and across the Caribbean. Paleotropical natives with a long history of use are likely to be safer remedies. Ethno-medicinal analyses of the pre- and post-2000 DM remedies of T&T, totaling 99 species, suggest that the centuries-old hot/cold folk disease-model was the model predominantly used in plant-selection. Parallels found between T&T folk concepts and biomedical mechanisms of DM provide probable bases for efficacy but the chronic use of purgatives and bitter-tasting plants is likely to be risky. Phytochemical analyses revealed that 69% of the tested plant extracts contained phenolic compounds, with more than half producing >80% alpha-glucosidase inhibition. Phenolic content and alpha-glucosidase inhibition were strongly correlated among food plants used as medicines, suggesting higher probability of selection as a result of non-target effects. The medicinal use of food plants may provide the best margins of safety and efficacy in identifying antidiabetic remedies. Together, these analyses showed how culture-specific plant-selection strategies can identify safe, useful remedies for developing countries to address their increasing DM prevalence in a cost-effective and sustainable manner.

Examining factors that affect vitamin D status in the fast-growing elderly population of Miami-Dade, Florida, is needed. Vitamin D deficiency in older adults has been linked to correlates of disability, including falls and fractures, and cardiovascular disease. The purpose of this study was to determine the proportion of vitamin D insufficient individuals and their relationship with vitamin D insufficiency in older adults (n=97) living in Miami-Dade. We evaluated the association between vitamin D status and 1) dual task physical performance to understand the link between vitamin D and cognition in the context of mobility; and 2) cardiometabolic risk, measured by galvanic skin response, pulse oximetry, and blood pressure to create a composite score based on autonomic nervous system and endothelial function. Participants completed baseline assessments that included serum levels of vitamin D, anthropometrics, body composition, dual task physical performance and cardiometabolic risk. Surveys to evaluate vitamin D intake, sun exposure, physical activity, and depressive symptoms were completed. Spearman’s correlations, independent t-tests, paired t-tests, repeated measures ANOVAs, and multiple logistic and linear regressions were used to examine the relationship of vitamin D insufficiency (25(OH)D /ml) and sufficiency (25(OH)D ≥30 ng/ml) with determinants of vitamin D status, dual task physical performance variables and cardiometabolic risk scores. Although the proportion of vitamin D insufficient individuals was lower when compared to the prevalance of the general United States elderly population, it was still common in healthy community-dwelling older adults living in Miami-Dade County, especially among Hispanics. Factors that affected skin synthesis (ethnicity, and sun exposure), and bioavailability/metabolism (obesity) were significant predictors of vitamin D status. Vitamin D insufficiency was not significantly correlated with worse dual task physical performance; however, cognitive performance was worse in the vitamin D insufficient group. Our results suggest a relationship of vitamin D insufficiency with executive dysfunction, and support an association with cardiometabolic risk using an innovative electro-sensor complex, possibly by modulating autonomic nervous system activity and vascular function, thus affecting cardiac performance.