Medicine and Health Sciences Commons^™

Structure-Activity Relationship Studies Of Synthetic Cathinones And Related Agents, Rachel A. Davies

Theses and Dissertations

Synthetic cathinones and related agents represent an international drug abuse problem, and at the same time an important class of clinically useful compounds. Structure-activity relationship studies are needed to elucidate molecular features underlying the pharmacology of these agents. Illicit methcathinone (i.e., MCAT), the prototype of the synthetic cathinone class, exists as a racemic mixture. Though the differences in potency and target selectivity between the positional and optical isomers of synthetic cathinones and related agents have been demonstrated to have important implications for abuse and therapeutic potential, the two MCAT isomers have never been directly compared at their molecular targets: the …

Regorafenib Enhances Lethality Of Sildenafil And Curcumin In Colorectal Cancer Cells, Kervin Benjamin Owusu

Theses and Dissertations

In the United States, more than 130,000 people will be diagnosed with colorectal cancer (CRC) each year and an estimated 50,000 people will die from the disease. Standard of care (SOC) therapies for CRC combine multiple cytotoxic chemotherapeutic drugs. These combinations have varying degrees of effectiveness and can often result in significant patient morbidity. For second recurrence patients, the multi-kinase inhibitor, regorafenib, is an approved agent, but is often poorly tolerated at current doses. In the current study, we propose to develop therapeutic regime of combining agents with modest toxicity profiles: curcumin and sildenafil with regorafenib. Using clinically achievable enterohepatic …

Eralpha Isoforms Modulate The Tumorigenicity Of 24r,25(Oh)2d3 In Estrogen-Responsive Cancer, Anjali Verma

Theses and Dissertations

Over 200,000 cases of breast cancer are diagnosed every year. Nearly 20% of these patients supplement their diets with some form of vitamin D. This high frequency of vitamin D supplement use may be due in part to research suggesting that cancer patients with higher serum vitamin D₃ levels have better prognoses than patients with low serum vitamin D_3. However, double-blind clinical trials on the efficacy of vitamin D₃ supplementation in breast cancer have been inconclusive. A recent meta-analysis showed evidence of reduced cancer recurrence in patients taking vitamin D₃ supplements who had ‘estrogen receptor positive’ …

Diuretic And Natriuretic Activity Of Faah Inhibition In The Renal Medulla: A Proposed Role Of Palmitoylethanolamide And Its Regulation By Renal Medullary Interstitial Cells, Sara Dempsey

Theses and Dissertations

Hypertension is a critical public health issue worldwide, and in the United States, it is the leading cause of heart disease, stroke, and kidney failure, contributing to more than 1,100 deaths per day. It is proposed that the renal medulla combats increased blood pressure by releasing a neutral lipid from the lipid droplets of medullary interstitial cells, termed medullipin, which induces diuresis- natriuresis and vasodepression. The renal medulla is enriched with fatty acid lipid ethanolamides including the endocannabinoid anandamide (AEA), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA), along with their primary hydrolyzing enzyme fatty acid amide hydrolase (FAAH). Our lab is investigating …

Modeling Pharmaceutical Inhibition Of Glucose-Stimulated Renin-Angiotensin System In Kidneys, Ashlee N. Ford Versypt, Minu R. Pilvankar, Hui Ling Yong

Biology and Medicine Through Mathematics Conference

No abstract provided.

Glycosaminoglycan Lyases In The Preparation Of Oligosaccharides, Alhumaidi B. Alabbas

Theses and Dissertations

Glycosaminoglycans are heterogeneous polysaccharides that mediate important biological functions. There has been considerable interest in deciphering the precise GAG sequences that are responsible for protein interactions. In fact, several GAG oligosaccharides have been discovered to date as targeting proteins with higher level of specificity. Yet, it has been difficult to develop GAG oligosaccharides as drugs. One of the key reasons for this state of art is that GAG synthesis is extremely challenging and is highly structure-specific. Thus, much of the biology and pharmacology of GAG remains unknown and unexploited to date.

An alternative approach is to prepare GAG oligosaccharides using …

Bromodomain And Extraterminal Domain (Bet) Inhibitor Rvx-208 Ameliorates Periodontal Bone Loss, Nicholas J. Clayton

Theses and Dissertations

Periodontal disease affects 47% of Americans over 30 and is a growing global concern. Current treatments for periodontal disease focus on the mechanical elimination of periodontal biofilms. Very few treatments are available that target the rampant, unregulated host immune response that is ultimately responsible for tissue degradation. BET proteins have been shown to play critical roles in inflammatory gene regulation and are therefore potentially ideal therapeutic targets for treating periodontal disease. RVX-208 is a selective BET-inhibitor with a high affinity for Bromodomain 2 (BD2) as compared to BD1 in BET proteins. Our previous studies have shown that RVX-208 inhibits inflammatory …

The Role Of Ceramide In Neutrophil Elastase Induced Inflammation In The Lungs, Sophia Karandashova

Theses and Dissertations

Alterations to sphingolipid metabolism are associated with increased pulmonary inflammation, but the impact of inflammatory mediators, such as neutrophil elastase (NE), on airway sphingolipid homeostasis remains unknown. NE is a protease associated CF lung disease progression, and can be found in up to micromolar concentrations in patient airways. While sphingolipids have been investigated in the context of CF, the focus has been on loss of cystic fibrosis transmembrane conductance regulator (CFTR) function. Here, we present a novel observation: oropharyngeal aspiration of NE increases airway ceramides in mice. Using a previously characterized mouse model of NE-induced inflammation, we demonstrate that NE …

Heparan Sulfate, A New Target For Platinum In Metastatic Tnbc, Samantha J. Katner

Theses and Dissertations

Abstract

Heparan Sulfate, A New Target for Platinum in Metastatic TNBC

Author: Samantha J. Katner, Ph.D.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy

Virginia Commonwealth University, 2018

Advisor: Dr. Nicholas Farrell, Professor, Chemistry Department

Heparan sulfate proteoglycans (HSPGs), composed of the linear polysaccharide heparan sulfate (HS) conjugated to a protein core, are located on the cell surface and extracellular matrix. The HS chains display varying degrees of sulfation, which constitutes the molecular recognition motif for many HS-protein interactions. HSPGs, associated growth factors, and heparanase promote tumor progression by facilitating invasion, angiogenesis, …

The Evaluation Of Mefloquine Drug Repurposing On Acute Myeloid Leukemia, Jessica L. Phan, Bhavuk Garg, Hrishikesh Mehta, Seth Corey

Undergraduate Research Posters

The aim of this study is to observe cell proliferation, cell viability, apoptosis, and autophagy on acute myeloid leukemia (AML) cell lines, NB4 and U937, with the drug repurposing of mefloquine (MQ). Methods such as the 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay and trypan blue staining have shown a decrease in live cells with high concentrations of mefloquine. Using their average perspective IC50 values of MQ concentration, Western blotting was applied by means of apoptosis and autophagy markers to determine if the induction of apoptosis and inhibition of autophagy was present in MQ-treated AML cells. The experiment will be continued with more …

Drug Delivery With Light, Patrick S. Dupart

Theses and Dissertations

Cancer is responsible for about 25% of deaths in developed countries and for 15% of all deaths worldwide. Cancer is a devastating disease and while there have been great advances in the development of anticancer drugs, off-target toxicity is a major limitation with conventional cancer chemotherapy. The consequence of this form of treatment results in the killing of healthy and rapidly-growing non-cancerous cells including cells in the bone marrow; hair follicles; and cells in the mouth, digestive tract, and reproductive system. In addition to these general effects, certain anticancer drugs can have other associated toxicities. For instance, the anticancer drug …

In Vitro Genetic Code Expansion And Selected Applications, Emil S. Iqbal

Theses and Dissertations

The ability of incorporation non-canonical amino acids (ncAAs) using translation offers researchers the ability of extend the functionality of proteins and peptides for many applications including synthetic biology, biophysical and structural studies, and discovery of novel ligands. Here we describe the three projects where the addition of ncAAs to in vitro translation systems creates useful chemical biology techniques. In the first, a fluorinated histidine derivative is used to create a novel affinity tag that allows for the selective purification of peptides from a complex mixture of proteins. In the second, the high promiscuity of an editing-deficient valine-tRNA synthetase (ValRS T222P) …

The Forensic Characterization Of Bacterial And Fungal Organisms In Traditional Chinese Medicine, Julia Grzymkowski, Christopher J. Ehrhardt, Justin L. Poklis, Michelle R. Peace

Undergraduate Research Posters

There has been an increase in use of Traditional Chinese Medicine (TCM) in the United States because they are less expensive and believed to be more effective with less adverse effects in comparison to traditional pharmaceutics. Therefore, sales have increased in the US, despite articles and case studies demonstrating the dangers, such as injury and death, related to TCM, stemming from improper labelling, toxic contaminants, and, in some cases, the presence of pathogenic bacteria. The aim of this study was to perform a survival experiment to demonstrate the importance of proper herbal brewing technique and to conduct a molecular and …

Galantamine's Deconstruction In The Quest Of A Pam Pharmacophore, Malaika Argade

Theses and Dissertations

Alzheimer’s disease is a progressive neurodegenerative disorder generally affecting people above the age of 65 years. Even though the pathophysiological hallmarks of AD were established more than a hundred years ago, there is yet to be a drug that can stop its characteristic neuronal damage. Of the five currently FDA-approved drugs, galantamine has a unique mechanism of action. Apart from being an AChE inhibitor, galantamine can effectively potentiate (positive allosteric modulator) the effect of agonists at nAChRs at concentrations lower than those required for its action as an AChE inhibitor. Perhaps the clinical benefits observed with galantamine are associated mainly …

Modulation Of Electron Transport By Metformin In Cardiac Protection: Role Of Complex I, Ahmed Abdul Hussein Mohsin

Theses and Dissertations

Modulation of mitochondrial complex I during reperfusion reduces cardiac injury. Complex I exists in two structural states: active (A) and deactive (D) with transition from A→D during ischemia. Reperfusion reactivates D→A with an increase in ROS production. Metformin preserves the D-Form. Our aim was to study the contribution of maintenance of deactivation of complex I during early reperfusion by metformin to protect against ischemia reperfusion injury. Our results showed that metformin decreased H9c2 cardiomyoblast apoptosis and total cell death following simulated ischemia for six hours followed by reoxygenation for twenty four hours compared to untreated cells. Reactive oxygen species (ROS) …

5-Ht2b Receptor-Mediated Cardiac Valvulopathy, Pallavi Nistala

Theses and Dissertations

5-HT_2B receptor agonism causes cardiac valvulopathy, a condition characterized by thickening of the heart valves and as a result, regurgitation of blood within the heart. The anti-obesity drug fenfluramine, which was originally prescribed as an anorectic, was withdrawn from the market due to causing cardiac valvulopathy. Fenfluramine, after metabolism by N-dealkylation, produces the metabolite norfenfluramine, which acts as a more potent valvulopathogen. The same was seen with MDMA (ecstasy), a popular drug of abuse, which is metabolized by N-dealkylation to produce MDA, a more potent valvulopathogen. Glennon and co-workers. studied a series of 2,5-dimethoxy-4- substituted phenylisopropylamines (DOX type) hallucinogens …

Effect Of Energy Metabolism On Nf-Kb Activity In Ovarian Cancer, Simren K. Bagri

Undergraduate Research Posters

NF-kB is a transcription factor involved in cancer cell growth and survival. The activation of NF-kB can be assessed by monitoring phosphorylation of RelA p65 at Ser-536, which is a surrogate of the NF-kB transcription factor activation. The objective of this study was to determine if the loss of ATP leads to NF-kB deficiency and thus, apoptotic cell death of “bad” cells in ovarian cancer cells. The independent variables were metformin (Met), an anti-diabetic medicine, another compound MinB functionally similar to Met and a glucose transporter inhibitor BAY-876. The dependent variables were the resulting effect of Met and MinB on …

Chemical Probes For Protein Α-N-Terminal Methylation, Brianna D. Mackie

Theses and Dissertations

While protein α-N-terminal methylation has been known for nearly four decades since it was first uncovered on bacteria ribosomal proteins L33, the function of this modification is still not entirely understood. Recent discoveries have demonstrated α-N-terminal methylation is essential to stabilize the interactions between regulator of chromosome condensation 1 (RCC1) and chromatin during mitosis, to localize and enhance the interaction of centromere proteins (CENPs) with chromatin, and to facilitate the recruitment of DNA damage-binding protein 2 (DDB2) to DNA damage foci. Identification of N-terminal methyltransferase 1 (NTMT1) unveiled the eukaryotic methylation writer for protein α-N-termini. In addition, NTMT2 that shares …

Proteomic Approach For Extracting Cytoplasmic Proteins From Streptococcus Sanguinis Using Mass Spectrometry, Fadi Elrami, Kristina Nelson, Ping Xu

Philips Institute for Oral Health Research Publications

Streptococcus sanguinis is a commensal and early colonizer of oral cavity as well as an opportunistic pathogen of infectious endocarditis. Extracting the soluble proteome of this bacterium provides deep insights about the physiological dynamic changes under different growth and stress conditions, thus defining “proteomic signatures” as targets for therapeutic intervention. In this protocol, we describe an experimentally verified approach to extract maximal cytoplasmic proteins from Streptococcus sanguinis SK36 strain. A combination of procedures was adopted that broke the thick cell wall barrier and minimized denaturation of the intracellular proteome, using optimized buffers and a sonication step. Extracted proteome was quantitated …

Investigation Of Anticoagulation Properties Of Sulfated Glycosaminoglycan Mimetics, Elsamani I. Abdelfadiel

Theses and Dissertations

Abstract

INVESTEGATION OF ANTICOAGULATION PROPERTIES OF SULFATED

GLYCOSAMINOGLYCAN MIMETICS

By Elsamani Ismail Abdelfadiel, MS

A thesis submitted in partial fulfillment of the requirements for the degree of Master of

Science at Virginia Commonwealth University

Virginia Commonwealth University, 2017.

Supervisor: Umesh R Desai

Professor, Department of Medicinal Chemistry

The existence of thrombosis in numerous pathophysiological situations formed a vast necessity for anticoagulation therapy. Thrombin and factor Xa are the only two factors of the entire coagulation cascade that have been major targets for regulation of clotting via the direct and indirect mechanism of inhibition. Our recent discovery of sulfated non-saccharide glycosaminoglycan …

Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis

Undergraduate Research Posters

“Kratom” is the common name for the botanical mitragyna speciosa. It is a tree native to Southeast Asia in which leaves contain the psychoactive alkaloids mitragynine and 7-hydroxymitragynine. Kratom is often ingested as teas, chewed, or smoked. It acts as a stimulant in small doses and as an opioid in large doses. Overdoses can result in vomiting, seizures, and death. Recently the Drug Enforcement Agency (DEA) placed Kratom on Schedule 1, but, due to public outcry, it was almost immediately removed.

Eleven kratom based products were obtained from various tobacco shops, “headshops” and via the internet including: Choice brand …

Can A Layer Of Antimicrobial Agents Be Placed Around Breast Implants To Prevent Staph Infections From Occurring?, Valerie L. Tran

Undergraduate Research Posters

The most common infection that occurs after breast augmentation is a staph infection. Currently, there are only three ways to treat this type of infection, all of which treat the breast implant after the infection has developed. The first option is to treat the infection with an oral antibiotic. If this doesn’t completely rid the infection, then intravenous antibiotics are used. If this too doesn’t remove the infection, then surgery will be performed to remove the breast implant and a new implant will be inserted. Although, these options have a low mortality rate, the success rate of completely getting rid …

Understanding And Targeting The C-Terminal Binding Protein (Ctbp) Substrate-Binding Domain For Cancer Therapeutic Development, Benjamin L. Morris

Theses and Dissertations

Cancer involves the dysregulated proliferation and growth of cells throughout the body. C-terminal binding proteins (CtBP) 1 and 2 are transcriptional co-regulators upregulated in several cancers, including breast, colorectal, and ovarian tumors. CtBPs drive oncogenic properties, including migration, invasion, proliferation, and survival, in part through repression of tumor suppressor genes. CtBPs encode an intrinsic dehydrogenase activity, utilizing intracellular NADH concentrations and the substrate 4-methylthio-2-oxobutyric acid (MTOB), to regulate the recruitment of transcriptional regulatory complexes. High levels of MTOB inhibit CtBP dehydrogenase function and induce cytotoxicity among cancer cells in a CtBP-dependent manner. While encouraging, a good therapeutic would utilize >100-fold …

Probing Allosteric, Partial Inhibition Of Thrombin Using Novel Anticoagulants, Stephen S. Verespy Iii

Theses and Dissertations

Thrombin is the key protease that regulates hemostasis; the delicate balance between procoagulation and anticoagulation of blood. In clotting disorders, like deep vein thrombosis or pulmonary embolism, procoagulation is up-regulated, but propagation of clotting can be inhibited with drugs targeting the proteases involved, like thrombin. Such drugs however, have serious side effects (e.g., excessive bleeding) and some require monitoring during the course of treatment. The reason for these side effects is the mechanism by which the drugs’ act. The two major mechanisms are direct orthosteric and indirect allosteric inhibition, which will completely abolish the protease’s activity. Herein we sought an …

Methcathinone Analogue Activity At The Human Serotonin Transporter, William Drake Varn

Theses and Dissertations

In the last few years, there has been continued concern about synthetic drug abuse in both the United States and worldwide. Small adjustments in drug compound structure often allow synthetic drug makers to manufacture a legal product that can produce the same highs as illegal counterparts. Unfortunately, this is happening faster than the government can outlaw the drug compounds, and a wide variety of synthetics are now appearing on the street. This study evaluated the effects on the human serotonin transporter of six different 4-para substituted methcathinone compounds. Using a Xenopus oocyte model, the efficacy of each MCAT analogue …

Can A Metallated Cyclen Species Be Used To Prepare New Odorants?, Jalynn Taylor-Farmer

Undergraduate Research Posters

Scientists in the fragrance industry are constantly searching for new odors to create as well as new, more efficient processes to create them. Scientists mainly look for new ways to synthesize fragrances that will reduce the impact on the environment, produce them at lower costs, produce higher yields, and sometimes to produce a more potent odor [4]. In this research, we investigated the use of metallic macrocycles and/or metal-dioxygen chemistry to prepare new fragrances.

Cyclen (1,4,7,10-tetraazacyclododecane) has significant uses in many pharmaceutical and medicinal research developments such as advances in targeted cancer and Alzheimer’s agents. Macrocyclic amines like cyclen are …

Characterization Of A Novel Protease In Staphylococcus Aureus, Adam L. Johnson

Theses and Dissertations

A newly discovered cysteine protease, Prp, has been shown to perform an essential, site-specific cleavage of ribosomal protein L27 in Staphylococcus aureus. In Firmicutes and related bacteria, ribosomal protein L27 is encoded with a conserved N-terminal extension that must be removed to expose residues critical for ribosome function. Uncleavable and pre-cleaved variants were unable to complement an L27 deletion in S. aureus, indicating that this N-terminal processing event is essential and likely plays an important regulatory role. The gene encoding the responsible protease (prp) has been shown to be essential, and is found in all organisms …

Chronic Behavioral And Cognitive Deficits In A Rat Survival Model Of Organophosphate Toxicity, Beverly Huang

Theses and Dissertations

Organophosphates (OPs) are a major class of pesticides and nerve agents that elicit acute toxicity by inhibiting acetylcholinesterase (AChE), the enzyme responsible for the degradation of the neurotransmitter acetylcholine in the central and peripheral nervous systems. Acetylcholine accumulation following extensive AChE inhibition leads to an acute cholinergic syndrome characterized by autonomic dysfunction, involuntary movements, muscle fasciculations, respiratory distress, and seizures. Despite their classification as moderate to highly toxic, OP pesticides are the most widely used class of insecticides in the U.S., and are even more commonly used worldwide. Additionally, there is a growing concern that OP nerve agents could be …

Dual Pi3k/Mtor Inhibition With Bez235 Augments The Therapeutic Efficacy Of Doxorubicin In Cancer Without Influencing Cardiac Function, David E. Durrant

Theses and Dissertations

Cancer continues to be a leading cause death in the United States despite improved treatments. Cancerous lesions form after acquiring oncogenic driver mutations or losing tumor suppressor function in normal cells. Traditional therapies have included use of genotoxic substances that take advantage of the increased growth rate and loss of tumor suppressor function to cause cell death. One such drug is the anthracycline antibiotic doxorubicin (DOX). DOX interchelates into DNA and disrupts transcriptional machinery while also poisoning topoisomerase II. This results in single and double stranded DNA breaks, which if severe enough leads to either necrotic or apoptotic cell death. …

Elucidation Of A Novel Pathway In Staphylococcus Aureus: The Essential Site-Specific Processing Of Ribosomal Protein L27, Erin A. Wall

Theses and Dissertations

Ribosomal protein L27 is a component of the eubacterial large ribosomal subunit that has been shown to play a critical role in substrate stabilization during protein synthesis. This function is mediated by the L27 N-terminus, which protrudes into the peptidyl transferase center where it interacts with both A-site and P-site tRNAs as well as with 23S rRNA. We observed that L27 in S. aureus and other Firmicutes is encoded with a short N-terminal extension that is not present in most Gram-negative organisms, and is absent from mature ribosomes. The extension contains a conserved cleavage motif; nine N-terminal amino acids are …