Doctor of Philosophy, The Ohio State University, 2019, Biomedical Sciences

Acute Myeloid Leukemia (AML) is the most common acute leukemia in adults affecting almost 12,000 people each year in the US. This disease is collectively characterized by an accumulation of rapidly proliferating neoplastic cells of the myeloid lineage with differentiation defects. In spite of the vast amount of information known about AML and the identification of favorable prognosis factors, a large percentage of patients relapse and succumb to this disease. In addition, the inter- and intra-tumor heterogeneity of AML makes the identification of therapeutic targets for this disease particularly challenging. Future studies are warranted to identify multi-targeted agents that could influence AML as a composite disease. A target that shows promise in targeting the bulk AML leukemic cell population is nicotinamide phosphoribosyltransferase (NAMPT). NAMPT is a protein involved in the generation of NAD+ in tumor cells, an important mediator of enzymatic reactions involved in various functions of leukemic disease progression. Leukemic blasts show a higher NAD+ turnover rate than normal cells, suggesting that NAD+ biosynthesis could be critically required in hematologic malignancies and therefore targeting the regeneration of NAD+ offers an attractive alternative strategy in AML. Inhibitors of NAMPT that have been described by others have shown potent anti-tumor activity and selectivity of several tumor models, including AML, while preserving the viability and functionality of normal tissues. While two agents targeting NAMPT have been tested in Phase I clinical trials, dose-limiting toxicities including thrombocytopenia and gastrointestinal toxicities led to their clinical discontinuation. Novel compounds with improved tolerability are needed. We sought to determine the mechanism of anti-tumor activity on AML leukemic cell population using a novel compound, KPT-9274, targeting NAMPT. We will also highlight several mechanisms used to antagonize AML disease progression v (open full item for complete abstract)

Committee: John Byrd (Advisor); Rosa Lapalombella (Advisor); Sameek Roychowdhury (Committee Chair); Vinay Puduvalli (Committee Member) Subjects: Biomedical Research; Oncology; Pharmacology

Doctor of Philosophy, Case Western Reserve University, 2023, Systems Biology and Bioinformatics

Recently, novel and unrecognized endogenous metabolites have been found to impact the risk of CVD not related to established risk factors (residual risk), including metabolites produced by gut microbes. Discovery platforms including metabolomics and metagenomics have identified new biomarkers associated with residual risk, but these platforms' usefulness is limited by the available methods of data analysis. This thesis aims to develop models of gut microbial metabolism using metagenomic data and new methods to identify unseparated structural isomers in metabolomics data. The gut microbial metabolism of trimethylamine-N-oxide, a metabolite associated with residual CVD risk, is used as a model system to develop predictive models of metabolism based on metagenomic information. An integrated analysis of metabolomics, metagenomics, and several other data types to predict circulating trimethylamine-N-oxide levels shows that while gut microbes play an essential role in trimethylamine-N-oxide synthesis, community composition does not quantitatively predict metabolism well enough to predict clinical risk. Analytical methods are developed to detect and identify structural isomers in metabolomics data. Two structural isomers, the terminal metabolites of niacin metabolism, are detected in human serum and characterized. Multiple clinical studies show these niacin metabolites are associated with residual CVD risk, and animal models show N1-methyl-4-pyridone-3-carboxamide (4PY) enhances vascular inflammation and thrombosis potential. Thus, new microbial and endogenous targets for therapy have been proposed, and new analytical methods have been introduced that may enable further study of residual CVD risk.

Committee: Mehmet Koyuturk (Committee Chair); Stanley Hazeen (Advisor); Daniel Rotroff (Committee Member); Andrew Pieper (Committee Member); Catherine Stein (Committee Member) Subjects: Analytical Chemistry; Animals; Biochemistry; Bioinformatics; Biology; Biostatistics; Food Science; Genetics; Health; Medicine; Microbiology; Molecular Biology; Molecular Chemistry; Molecules; Nutrition; Organic Chemistry; Public Policy

Master of Science (MS), Wright State University, 2021, Pharmacology and Toxicology

In skin connective tissue, dermal fibroblasts appear to be the most prevalent cell type. They are in charge of making the extracellular matrix that makes up the skin's connective tissue, and also involved in wound healing. Moreover, they produce Insulin-like growth factor-1 (IGF-1) which helps in activation of Insulin growth factor-1 receptor (IGF-1R). This receptor helps to control cell proliferation and responses to DNA-damaging substances such as UVB radiation, reactive oxygen species (ROS), and therapeutic drugs. According to our findings, lack of IGF-1 expression in the dermis of elderly patients due to fibroblast senescence (senescence is characterized by which cells enter a condition of irreversible growth arrest after irreversibly avoiding dividing without enduring cell death) has been linked to an increased incidence of skin cancer in the epidermal keratinocyte. Our group resolved that pretreatment with creatine monohydrate and nicotinamide shows a protective effect on oxidative-stress senescence. Based on this study, the present project was designed to study the effect of creatine and nicotinamide on stress-induced reactive oxygen species (ROS) generation as a possible mechanism for their protective effects. Similarly, the present study also examined how the pro-energetics acts on senescence as a post-treatment. Using primary human dermal fibroblasts exposed to H2O2 in vitro, via ROS staining, beta-galactosidase staining, and RT-qPCR, we discovered that pre-treatment with creatine and nicotinamide reduces oxidative stress-induced ROS levels, while post-treatment with creatine or nicotinamide after H2O2 had no effect on stress-induced senescence.

Committee: Jeffrey B. Travers M.D., Ph.D. (Advisor); Michael G. Kemp Ph.D. (Committee Member); Ravi P. Sahu Ph.D. (Committee Member) Subjects: Pharmacology; Toxicology

Master of Science (MS), Wright State University, 2020, Pharmacology and Toxicology

Dermal fibroblasts provide structural support by producing collagen and other structural/support proteins beneath the epidermis. Fibroblasts also produce Insulin-like growth factor-1 (IGF-1), which binds to the IGF-1 receptors (IGF-1Rs) on keratinocytes to activate signaling pathways that regulate cell proliferation and cellular responses to genotoxic stressors like ultraviolet B radiation found in sunlight. Our group has determined that the lack of IGF-1 expression due to fibroblast senescence in the dermis of geriatric individuals is correlated with an increased incidence of skin cancer in geriatric patients. The present studies were designed to test the hypothesis that pro-energetics like creatine monohydrate and nicotinamide can protect fibroblasts against senescence. To that end, we used an experimental model of senescence in which primary human fibroblasts are treated with hydrogen peroxide (H2O2) in vitro, with senescence measured by staining for beta-galactosidase activity (+beta-gal), p21 protein expression and senescence associated secretory phenotype (SASP) cytokine mRNA levels. We also determined the effect of H2O2 on IGF-1 mRNA and protein expression. Our studies indicate that pretreatment with creatine monohydrate or nicotinamide protects human fibroblasts from the H2O2-induced cell senescence. These studies suggest a potential strategy for protecting fibroblasts in geriatric skin from undergoing stress-induced senescence, which may maintain IGF-1 levels and therefore limit carcinogenesis in epidermal keratinocytes.

Committee: Jeffrey B. Travers M.D., Ph.D. (Advisor); Michael Kemp Ph.D. (Committee Member); Yong-jie Xu M.D., Ph.D. (Committee Member) Subjects: Pharmacology

Master of Science in Pharmaceutical Sciences, University of Toledo, 2004, Pharmaceutical Science

The purpose of this study was to examine the nature of the solid-state interaction between ibuprofen and nicotinamide and determine the solubility enhancement achieved by using nicotinamide as a hydrotropic agent and develop a suitable efficacious formulation. Ibuprofen-nicotinamide binary mixtures were prepared by solvent evaporation method. DSC studies suggested complex formation between ibuprofen and nicotinamide with 1:1 stoichiometry in solid state. UV-Visible spectroscopy suggested that the interaction was weak. Disappearance of the broad hydrogen bonding peak in the FTIR spectrum for the complex predicted greater solubility for the complex. Proton NMR studies ruled out the possibility of any chemical interaction between the two compounds. PXRD and microscopic studies showed that the crystallinity of the complex was remarkably reduced. All the studies predicted greater solubility for ibuprofen in complexed form. The HPLC studies showed that solubility was enhanced 62 times in the suspension when the concentration of nicotinamide was 13.3 mg/mL.

Committee: Kenneth Alexander (Advisor) Subjects: Health Sciences, Pharmacy

Doctor of Philosophy, Case Western Reserve University, 2009, Chemical Engineering

The goal of this research was to apply thick-film screen printing technology to produce a single-use, disposable, cost-effective electrochemical biosensor prototype in large scale. Iridium nanoparticles supported by carbon were selected to modify the electrode of the biosensor for its excellent catalytic effect towards the commonly detected electrochemical active species, i.e., hydrogen peroxide, nicotinamide adenine dinucleotide (reduced form, NADH), and nicotinamide adenine dinucleotide (oxidized form, NAD+). The development of this electrochemical biosensor prototype can establish a platform technology for various analytes of clinical importance. This study focused on the biosensing of the following analytes related to diabetes, i.e., 3-hydroxybutyrate (3HB), fructosyl valine, and the HbA1c, providing an analytical tool for diabetic patient management. The first part of this study discusses the importance of developing a point-of-care amperometric biosensor to detect 3-hydroxybutyrate (3HB) for diabetic patient management. Current electrochemical detection methods for 3HB require at least two stepwise reactions or a mediator. The detection method in this study only requires a single reaction step without any mediator, which can potentially also be more accurate, sensitive, cost-effective and stable over the long term. In this detection method, the enzyme D-3-hydroxybutyrate dehydrogenase (3HBDH, EC 1.1.1.30) was immobilized on the iridium–modified sensor prototypes which detect the NADH produced by the reaction of 3HB with NAD+ in the presence of 3HBDH. This microelectrode quantified the NADH electrochemically, which produced an electrical current that would then be used to quantify the concentration of 3HB. The interferences from uric acid, NAD+, and serum were measured. It was concluded that the level of 3HB could still be quantified well in the presence of these interfering species. Spectrometric measurements of NADH and 3HB were performed in both PBS and bov (open full item for complete abstract)

Committee: Chung-Chiun Liu (Committee Chair); Vernon Anderson (Committee Member); Heidi Martin (Committee Member); Harihara Baskaran (Committee Member) Subjects: Biochemistry; Biomedical Research; Chemical Engineering; Engineering