published_or_final_version / Zoology / Master / Master of Philosophy

Phosphoinositide 3-kinases (PI3Ks) are a family of proteins involved in many different aspects of cell signaling. To date, eight different human PI3K isoforms have been identified, and distinct roles are beginning to emerge for each family member. Statins, HMG co-A reductase inhibitors used clinically to lower LDL cholesterol levels, also act through the PI3K signaling pathway to regulate cholesterol independent of their lipid-lowering effects. In an effort to discover the role of pl 10f3 in mediating non-lipid lowering effects of pravastatin, a mutant of p110(3 was overexpressed in human coronary artery endothelial cells (HCAEC) to form a dominant negative model (p110(3 DN). Silence si-RNA as an alterative tool was also optimized to diminish p110(3 protein expression successfully. HepG2 3: RE was used to monitor statins function by assaying luciferase expression. Results from these studies will determine the contribution of p110f3 in mediating selective cellular responses to statin. / Department of Biology

Thesis (Ed. D.)--Teachers College, Columbia University. / Typescript; issued also on microfilm. Sponsor: Bernard Gutin. Dissertation Committee: Isobel Contento. Bibliography: leaves 75-83.

Thesis (M.S.)--University of Toledo, 2010. / Typescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Masters of Science Degree in Pharmaceutical Sciences, Administrative Pharmacy Option." "A thesis entitled"--at head of title. Title from title page of PDF document. Bibliography: p. 61-69.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph.D.)--York University, 2004. Graduate Programme in Biology. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99153

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu). / A role has been proposed for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in central cardiovascular control. This proposa 1 was based on the cardiovascular effects of agents which block or mimic the action of GABA on the post-synaptic membrane. This dissertation reported the cardiovascular effects of 3-mercaptopropionic acid (3-MP), an agent which inhibits GABA biosynthesis in the pre-synaptic nerve terminal in anesthetized guinea pigs. 3-MP interrupts GABAergic transmission by decreasing the amount of GABA in the brain. The effect of 3-MP on mean arterial pressure, heart rate and barorflex-induced bradycardia was determined as well as the mechanism(s) involved in observed changes. The content of GABA in four regions of the brain (hypothalamus, medulla, cerebellum and occipital cortex) was determined at the end of each experiment. In anesthetized guinea pigs, 3-MP (195 mg/kg, i.p.) elicited a biphasic response (Type I) in the majority of animals. This response consisted of sympathetically-mediated hypertension and tachycardia superseded by vagally-mediated bradycardia. The other response (Type II) consisted of only the sympathetically-mediated effects. The Type II response was associated with animals in which the vagus nerves were functionally impaired. In all brain regions measured, the GABA levels of both Types I and II were significantly lower than those of control animals. The sympathetically-mediated effects of 3-MP were reversed by chlordiazepoxide, a GABA-facilitory agent. Therefore, the 3-MP-induced cardiovascular effects appeared to reflect GABAergic activity in the bra in which resulted from a reduction of GABA content. The two phases of the Type I response may have resulted from a reduction of GABA content in specific brain regions. A reduction in hypothalamic GABA levels appeared to be related to the sympathetic activation and a reduction in medullary GABA levels appeared to be related to the vagal activation. In unparalyzed animals, 3-MP elicited convulsive movements as well as the described effects on the cardiovascular system. The centrally acting anticonvulsant phenytoin stopped 3-MP-induced motor manifestations of seizure activity without altering either blood pressure or heart rate. Therefore, the cardiovascular effects of 3-MP appeared to occur independent of the convulsive effect of this agent. These results support the hypothesis of GABAergic involvement in the central control of autonomic outflow to the cardiovascular system. The inability of phenytoin to reverse the cardiovascular effects of 3-MP suggests that these effects were independent of 3-MP-induced seizures.

Finally, the pharmacodynamic effects of propranolol powder formulation with different buffering were carried out in two healthy male subjects. The maximal reduction in heart rate was found at the saliva pH of 7.6, which corresponded to the pHmax of propranolol. A buffered propranolol sublingual tablet was then prepared to achieve the saliva pH around 7.6. The preliminary investigation confirmed that the sublingually administrated buffered propranolol tablet produced a faster and more pronounced heart rate reduction than the non-buffered commercial propranolol tablet. / Firstly, the use of the HO-1-u-1 cell culture for screening sublingual drug delivery was validated. The cells were seeded on cell culture inserts. The integrity of cell layers, inter-passage variation and directionality were assessed by measuring the resistance and the permeability of standard markers, beta-blockers and calcium channel blockers. The effect of pH, osmolarity and a permeation enhancer (GDC) were also studied. The results showed that HO-1-u-1 cells grown on inserts formed stratified and epithelial-like structure that preserved the typical histological feathers of the normal human sublingual epithelium. The maximal integrity was reached in 23 days. The Papp of beta-blockers and calcium channel blockers ranged from 2.89+/-0.17 x 10 -6 cm/s to 6.37+/-0.37 x 10-6 cm/s. The permeability of selected beta-blockers under different pH, osmolarity and GDC revealed that enhancing effects were significant for hydrophilic compounds but less for lipophilic compounds. / Secondly, fresh porcine sublingual mucosa was prepared and compared to the cell line model. Good correlations were obtained for both the Papp of beta-blockers and the enhancement ratios of pH and GDC between the two models. / The aims of the present study are (1) to develop and validate a human sublingual epithelial cell line model and (2) to demonstrate the application in sublingual development of cardiovascular drugs. / Thirdly, the steady-state flux (Jss) at various pH levels were measured. Results show that saturated propranolol solution at pH 7.0--7.6 resulted in a much higher Jss than the solution at other pHs. These data led to the development of theoretical equations for predicting the optimum pH (pHmax) for ionizable compounds. The calculation fitted well with the experimental data. / Wang Yanfeng. / Advisers: Moses S. S. Chow; Zhong Joan Zuo. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 184-). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Wong, Mei Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 207-251). / Abstracts in English and Chinese. / ABSTRACT --- p.i / 摘要 --- p.iv / ACKNOWLEDGEMENTS --- p.vi / PUBLICATIONS BASED ON WORK IN THIS THESIS --- p.vii / ABBREVIATIONS --- p.viii / TABLE OF CONTENTS --- p.x / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Diabetes Mellitus --- p.1 / Chapter 1.2 --- Structure and Functions of the Pancreas --- p.2 / Chapter 1.2.1 --- Size of Pancreatic β-Cells --- p.4 / Chapter 1.2.2 --- Signaling Pathways of Insulin Secretion from Pancreatic β-Cells --- p.4 / Chapter 1.3 --- Classification of Diabetes --- p.6 / Chapter 1.3.1 --- Type 1 Diabetes --- p.6 / Chapter 1.3.2 --- Type 2 Diabetes --- p.8 / Chapter 1.4 --- Pathologies of Type 2 Diabetes --- p.9 / Chapter 1.4.1 --- Hyperglycemia --- p.9 / Chapter 1.4.1.1 --- A dvanced Glycosylation End Products --- p.11 / Chapter 1.4.1.2 --- Protein Kinase C Activation --- p.13 / Chapter 1.4.1.3 --- The Glucosamine Pathway --- p.14 / Chapter 1.4.1.4 --- Oxidative Stress --- p.15 / Chapter 1.4.2 --- Insulin Resistance --- p.15 / Chapter 1.4.3 --- Loss of β-Cell Mass and β-Cell Dysfunction --- p.18 / Chapter 1.5 --- Complications of Diabetes Mellitus --- p.21 / Chapter 1.5.1 --- Cardiovascular Diseases --- p.21 / Chapter 1.5.2 --- Diabetic Retinopathy --- p.22 / Chapter 1.5.3 --- Diabetic Nephropathy --- p.23 / Chapter 1.5.4 --- Neuropathy --- p.24 / Chapter 1.6 --- Anti-Diabetic Drugs for Type 2 Diabetes Mellitus --- p.25 / Chapter 1.6.1 --- Secretagogues --- p.25 / Chapter 1.6.2 --- Sensitizers --- p.26 / Chapter 1.6.3 --- Alpha-Glucosidase Inhibitors --- p.27 / Chapter 1.6.4 --- Peptide Analogs --- p.27 / Chapter 1.6.4.1 --- Incretin Mimetics --- p.27 / Chapter 1.6.4.2 --- Dipeptidyl Peptidase-4 Inhibitors --- p.28 / Chapter 1.7 --- Insights of Porcine Islets in Treatment of Diabetics --- p.28 / Chapter 1.8 3 --- -Hydroxy-3-Methylglutaryl Coenzyme A Reductase (HMG CoA Reductase) --- p.31 / Chapter 1.8.1 --- Statins --- p.32 / Chapter 1.8.2 --- Pleiotropic Effects of Statins --- p.36 / Chapter 1.8.2.1 --- Statins and Isoprenylated Proteins --- p.36 / Chapter 1.8.2.2 --- Statins and Endothelial Functions --- p.38 / Chapter 1.8.2.3 --- Statins and Platelet Functions --- p.39 / Chapter 1.8.2.4 --- Statins and Plaque Stability --- p.39 / Chapter 1.8.2.5 --- Statins and Vascular Inflammation --- p.40 / Chapter 1.9 --- Clinical Studies of Statins on Diabetics --- p.41 / Chapter 1.10 --- Possible Factors Involved in Simvastatin-Regulated Insulin Secretion --- p.44 / Chapter 1.10.1 --- AMP-Activated Protein Kinase --- p.44 / Chapter 1.10.2 --- Caveolin-1 --- p.46 / Chapter 1.10.3 --- Sterol-Regulatory Elementary Binding Protein --- p.50 / Chapter 1.10.4 --- Protein Phosphatase 2A --- p.52 / Chapter 1.10.5 --- Calcium Sensing Receptor --- p.55 / Chapter 1.11 --- Objectives of Study --- p.59 / Chapter CHAPTER 2 --- MATERIALS AND METHODS --- p.60 / Chapter 2.1 --- Materials --- p.60 / Chapter 2.1.1 --- Solutions --- p.60 / Chapter 2.1.2 --- Antibodies --- p.63 / Chapter 2.2 --- Methods --- p.64 / Chapter 2.2.1 --- Maintenance of Pancreas Function --- p.64 / Chapter 2.2.2 --- Islet Isolation --- p.65 / Chapter 2.2.3 --- Hematoxylin and Eosin (H&E) Staining --- p.65 / Chapter 2.2.4 --- Simvastatin and Simvastatin-Na+ --- p.66 / Chapter 2.2.5 --- AICAR --- p.67 / Chapter 2.2.6 --- Compound C --- p.67 / Chapter 2.2.7 --- Incubation of Islets --- p.67 / Chapter 2.2.8 --- Western Blot --- p.68 / Chapter 2.2.9 --- Enzyme-Linked Immunosorbent Assay (ELISA) --- p.69 / Chapter 2.2.10 --- Statistical Analysis --- p.71 / Chapter CHAPTER 3 --- HISTOLOGY OF PORCINE PANCREATIC ISLETS OF LANGERHANS --- p.72 / Chapter 3.1 --- Comparison of Sizes of Porcine Pancreatic Islets in Histological Sections of Pancreas --- p.72 / Chapter CHAPTER 4 --- PROTEIN EXPRESSION OF HMG COA REDUCTASE --- p.75 / Chapter 4.1 --- Effect of Incubation Time on HMG CoA Reductase Expression --- p.75 / Chapter 4.2 --- Short-Term Effect of Simvastatin on HMG CoA Reductase Expression --- p.78 / Chapter 4.3 --- Long-Term Effect of Simvastatin on HMG CoA Reductase Expression --- p.81 / Chapter 4.4 --- Effect of Osmolality on HMG CoA Reductase Expression --- p.83 / Chapter 4.5 --- Effect of Simvastatin on Ser871 p-HMG CoA Reductase Expression --- p.87 / Chapter CHAPTER 5 --- EVALUATION OF THE ROLE OF SIMVASTATIN IN INSULIN SECRETION VIA HMG CO A REDUCTASE REGULATION --- p.90 / Chapter 5.1 --- Effect of Simvastatin on Insulin Secretion --- p.90 / Chapter 5.2 --- Effect of Different Concentrations of Simvastatin on Insulin Secretion --- p.94 / Chapter 5.3 --- Effect of Simvastatin on Insulin Content --- p.96 / Chapter CHAPTER 6 --- ROLE OF AMPK EXPRESSION IN INSULIN SECRETION PATHWAY --- p.100 / Chapter 6.1 --- Effect of Simvastatin on Thr172 p-AMPK α and AMPK α1 Expressions --- p.100 / Chapter 6.2 --- Evaluation of the Role of Simvastatin in AMPK Regulation --- p.104 / Chapter 6.3 --- Evaluation of the Role of PP2A in AMPK Regulation --- p.108 / Chapter 6.4 --- Evaluation of the Role of Simvastatin on Insulin Secretion via AMPK Regulation --- p.111 / Chapter 6.4.1 --- AMPK Regulation on Releasable Insulin Secretion --- p.111 / Chapter 6.4.2 --- AMPK Regulation on Non-Releasable Insulin Content and Total Insulin Content --- p.112 / Chapter CHAPTER 7 --- EFFECT OF SIMVASTATIN ON THE EXPRESSION OF REGULATORY PROTEINS INVOLVED IN INSULIN SECRETION --- p.119 / Chapter 7.1 --- Effect of Simvastatin on SREBP-2 Expression --- p.119 / Chapter 7.2 --- Effect of Simvastatin on Caveolin-1 Expression --- p.121 / Chapter 7.3 --- Effect of Simvastatin on Calcium Sensing Receptor Expression --- p.123 / Chapter CHAPTER 8 --- EFFECT OF SIMVASTATIN-NA+ ON INSULIN SECRETION --- p.126 / Chapter 8.1 --- Effect of Simvastatin-Na+ on HMG CoA Reductase Expression --- p.126 / Chapter 8.2 --- Effect of Simvastatin-Na+ on Insulin Secretion --- p.128 / Chapter 8.3 --- Effect of Different Concentrations of Simvastatin-Na+ on Insulin Secretion --- p.130 / Chapter 8.4 --- Effect of Simvastatin-Na+ on Insulin Content --- p.132 / Chapter CHAPTER 9 --- EFFECT OF PRAVASTATIN ON INSULIN SECRETION --- p.136 / Chapter 9.1 --- Effect of Pravastatin on Insulin Secretion --- p.136 / Chapter 9.2 --- Effect of Pravastatin on Insulin Content --- p.138 / Chapter CHAPTER 10 --- EFFECT OF METHYL-B-CYCLODEXTRIN ON INSULIN SECRETION --- p.142 / Chapter 10.1 --- Effect of Methyl-β-cyclodextrin on Insulin Secretion --- p.142 / Chapter 10.2 --- Effect of Methyl-β-cyclodextrin on Insulin Content --- p.144 / Chapter CHAPTER 11 --- DISCUSSION --- p.149 / Chapter 11.1 --- Importance of Studying Porcine Pancreatic Islets and Islet Distribution --- p.150 / Chapter 11.2 --- Screening of Concentration and Incubation Time of Simvastatin on Porcine Pancreatic Islets --- p.152 / Chapter 11.3 --- Glucose-Independent Effect of Simvastatin on Protein Expression of HMG CoA Reductase --- p.154 / Chapter 11.4 --- Role of AMPK in HMG CoA Reductase-Modulated Insulin Secretion --- p.159 / Chapter 11.5 --- Role of SREBP-2 in Simvastatin-Modulated Regulation --- p.174 / Chapter 11.6 --- Role of Calcium Sensing Receptor in Simvastatin-Modulated Regulation --- p.175 / Chapter 11.7 --- Role of Caveolin-1 in Simvastatin-Modulated Regulation --- p.179 / Chapter 11.8 --- "Effects of Simvastatin-Na+， Pravastatin and Methyl-β-cyclodextrin, and Importance of Endoplasmic Reticulum in Insulin Secretion" --- p.183 / Chapter CHAPTER 12 --- CONCLUSIONS AND FURTHER STUDIES --- p.197 / Chapter 12.1 --- Conclusions --- p.197 / Chapter 12.2 --- Further Studies --- p.203 / REFERENCES --- p.207