Pharmacology Commons^™

Exposure To Pm2.5 And Aging., Daniel Chris Gomes

Electronic Theses and Dissertations

Inhalation of fine airborne particulate matter (PM_2.5) is an environmental risk factor for numerous health disorders, including cardiovascular diseases (CVD). While several studies have shown that PM_2.5 exposure can induce oxidative stress, DNA damage, and inflammation, the underlying mechanisms that translate these effects into systemic pathology remain poorly understood. Some recent studies have shown that PM_2.5 exposure can lead to telomere shortening in leukocytes, but the generality of this outcome and contribution to endothelial dysfunction has not yet been fully explored. We hypothesized that PM_2.5inhalation accelerates cellular aging and senescence in both circulating peripheral …

A Ralgef Inhibitor Suppresses Lung Cancer Stem Cell Development And Tumorigenesis., Raphael Ngozichi Suarez Jigo

Electronic Theses and Dissertations

The RALGEF family of proteins are direct downstream effectors of the RAS oncoprotein. RALGEFs act as guanine nucleotide exchange factors (GEFs) for downstream RAL proteins, thus tying RAS to the regulation of RAL. Genetic studies have demonstrated RAL proteins to be key drivers of RAS-driven transformation and metastasis. Furthermore, this pathway has been implicated in chemoresistance, exocyst-mediated transport, and the modulation of cancer stem cells. Previous work in our lab reported the activity of a novel pan-RALGEF inhibitor (C4-180) against RAS-driven pancreatic cancer models. Here we show the agent to be active against in vitro and in vivo models of …

Effect Of Histidine Tag On The Enzymatic Activity Of Pseudolysin And Its Interaction With The Streptomyces Metalloprotease Inhibitor (Smpi) Protein, Adewale Adeboye Adewole

Electronic Theses and Dissertations

Pseudolysin (PLN) protein is a major virulent factor in Pseudomonas aeruginosa infection. PLN belongs to the family of zinc-dependent metalloproteases. It is naturally inhibited by a smaller protein called streptomyces metalloprotease inhibitor (SMPI), secreted by Streptomyces nigrescens. Previous and current studies demonstrate that the interaction between PLN and SMPI offers unique mechanistic insights for drug development against infections caused by P. aeruginosa. This study investigated the effect of N-terminal Histidine (His) tag on the enzymatic activity of PLN and its interaction with SMPI. His-tagged PLN and SMPI proteins were expressed in bacteria and purified by affinity chromatography …

Investigating The Role Of The Hypocretin/Orexin System In A Novel Model Of Polysubstance Dependence, Tyler Zarin

Electronic Theses and Dissertations

Substance use disorders (SUD) in the United States are steadily increasing. Potent and dangerous substances such as methamphetamine (MA) and fentanyl (FEN) are often co-used as a polysubstance (POLY), either intentionally or unknowingly as FEN is a common adulterant. SUD is characterized by physiological and psychological dependence involving the negative reinforcement of anhedonia and withdrawal which drive hypermotivated drug-taking behaviors. Current theory suggests that recruitment of hypocretin/orexin (HCRT) neuropeptide in reward and stress associated brain regions contributes to drug dependence. Despite strong evidence for HCRT’s role in mono-drug dependence, a relevant model for POLY dependence has yet to be developed, …

The Multipurpose Dna Repair/Redox Protein Ape1 In Rodent And Human Lewy Body Disease, Kristin Marie Miner

Electronic Theses and Dissertations

Lewy body disorders are a family of neurodegenerative conditions characterized by proteostatic and redox disequilibrium, leading to deposition of the abundant protein α-synuclein in hallmark inclusions and oxidative damage to DNA. Sublethal oxidative DNA damage in neurons is repaired predominantly by the base excision repair pathway, which involves the coordinated activity of several enzymes, including apurinic/apyrimidinic endonuclease 1 (APE1). Despite emerging connections between α-synuclein, oxidative stress, and DNA damage/repair, along with evidence demonstrating the multifunctional nature of APE1, the link between APE1 and α-synuclein has not yet been explored.

Here, we conducted a broad investigation of APE1 in the context …

The Effect Of Novel Microtubule Modulators On Experimental Lewy Body Disease, Anuj S. Jamenis

Electronic Theses and Dissertations

In Lewy body disorders, α-synuclein aggregates are believed to destabilize the microtubular framework. However, microtubules are a challenging therapeutic target, as excessive rigidity or flexibility afforded by microtubule modulators may be neurotoxic. Thus, the objective of the present study was to evaluate dual-acting microtubule- stabilizing/destabilizing agents in cellular and animal models of early-stage Lewy body disease.

In Aim 1 we tested the dual-acting tricylic pyrimido[4,5-b]indole analogs AG161-47 and AG161-41 in an in vitro preformed fibril induced model of Lewy body disease. We found that both compounds reduced preformed fibril-seeded α-synucleinopathy without toxicity in primary hippocampal cultures. AG161-47 subtly impacted microtubule …

The Reinforcement Enhancing Effects Of Delta-9-Tetrahyrdrocannabinol (Thc) In Male And Female Rats, Kynah Walston

Electronic Theses and Dissertations

Cannabis is widely consumed by humans for pharmacological effects that are mediated by THC, though there is little evidence that THC is a primary reinforcer in non-human animal models. We hypothesized that THC may have potent reinforcement enhancing effects, comparable to other drugs (e.g., nicotine and caffeine) which are also widely consumed by humans, but difficult to establish as primary reinforcers in non-humans. In three experiments with male and female rats saccharin (SACC) or a visual stimulus (VS) served as reinforcers for operant behavior. We explored several pharmacological parameters of THC on responding for SACC or VS, including THC dose, …

Soluble Epoxide Hydrolase Inhibition: A Novel Therapeutic Strategy For Alcohol-Associated Liver Disease., Jeffrey Warner

Electronic Theses and Dissertations

Introduction Alcohol-associated liver disease (ALD) is a common chronic liver disease and healthcare burden, and a spectrum of pathologies ranging from steatosis to steatohepatitis, fibrosis, and alcohol-associated hepatitis (AH). Despite its prevalence, there are limited effective therapeutic options for the treatment of ALD/AH. Previous evidence suggested that inhibition of soluble epoxide hydrolase (sEH), a lipid metabolism enzyme which degrades beneficial metabolites of dietary polyunsaturated fatty acids, may be a beneficial strategy. The central hypothesis of the current dissertation is that sEH inhibition will ameliorate alcohol-associated liver injury and inflammation in mouse models of ALD. Methods To determine the efficacy of …

Modulatory Effects Of Deacetylated Sialic Acids On Breast Cancer Resistance Protein-Mediated Multidrug Resistance And Receptor Tyrosine Kinase-Targeted Therapy, Isaac Tuffour

Electronic Theses and Dissertations

Multidrug resistance (MDR) remains a major challenge in cancer treatment, accounting for over 90% of chemotherapeutic failures. Cancers utilize sugar residues to engage in multidrug resistance. The underlying mechanism of action involving glycans, specifically the glycan sialic acid (Sia) and its various functional group alterations, has not been explored. ATP-binding cassette (ABC) transporter proteins, key proteins utilized by cancers to engage in MDR pathways, contain Sias in their extracellular domains. Modulating the expression of acetylated-Sias on Breast Cancer Resistance Protein (BCRP), a significant ABC transporter implicated in MDR, in lung and colon cancer cells directly impacted the ability of cancer …

Investigation Of Human N-Acetyltransferases (Nat1 And Nat2) Genetic Polymorphisms In Susceptibility To Aromatic Amine And Alkylaniline Genotoxicity., Mariam Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT1 and NAT2 genotypes. We hypothesize that different NATs alleles will impact levels of N-acetylation, HPRT mutations, DNA damage and oxidative stress induced by carcinogens. NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and NAT1*4, NAT1*14B, NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of benzidine, β-naphthylamine (BNA), and 4, 4’-methylene bis (2-chloroaniline) (MOCA) as aromatic amines and 3,4-dimethylaniline (3,4-DMA) as one of alkylanilines and their associated toxicity. Our …

Validation Of The 40 Hz Auditory Steady State Response As A Pharmacodynamic Biomarker Of Evoked Neural Synchrony, Muhammad Ummear Raza

Electronic Theses and Dissertations

Schizophrenia is a troubling and severe mental illness that is only incompletely treated by currently available drugs. New drug development is hindered by a scarcity of functionally relevant pharmacodynamic biomarkers that are translatable across preclinical and human subjects. Although psychosis is a major feature of schizophrenia, cognitive and negative symptoms determine the long-term functional outcomes for patients. Stimulus-evoked neural synchrony at gamma (~ 40 Hz) frequency plays an important role in the processing and integration of sensory information. Not surprisingly, schizophrenia patients show deficits in gamma oscillations. NMDA receptor (NMDAR) activation on fast-spiking parvalbumin-positive interneurons is deemed important for the …

Sex-Specific Effects Of Chaperone And Glial Defenses On Experimental Lewy Body Disease, Tarun Bhatia

Electronic Theses and Dissertations

Lewy body disorders are a group of neurodegenerative conditions characterized by the pathological misfolding and aggregation of the abundant protein, α-synuclein. The most common Lewy body disorders are Parkinson’s disease and dementia with Lewy bodies. Apart from ageing, male sex is a major risk factor for Lewy body disorders, as men are at ~1.5-fold higher risk for these diseases than women. Yet, preclinical studies on Lewy body disorders rarely examine sex as a biological variable, and the mechanisms underlying sex-skewedness in disease risk remain undetermined.

Here, we developed a sex-stratified model of Lewy body disorders by exposing primary neurons harvested …

Cannabinoids And Retinal Fibrotic Disorders., Lucy June Sloan

Electronic Theses and Dissertations

Retinal fibrosis is detrimental to vision. Retinal pigment epithelial (RPE) cells contribute to several retinal fibrotic diseases. Upon exposure to TGF-β, a key fibrotic cytokine, RPE cells trans-differentiate to myofibroblasts marked by the integration of α-SMA fibers into F-actin stress fibers, which confer strong contractility. Myofibroblasts produce and contract the collagen-rich fibrotic scar and disrupt retinal architecture. In this study, we investigated the in vitro effects of the putative endocannabinoid compound N-oleoyl dopamine (OLDA) on TGF-β2 induced porcine RPE cell contraction and α-SMA expression. Using an in vitro collagen matrix contraction assay, we found that OLDA inhibited TGF-β2 induced contraction …

Particulate Hexavalent Chromium Inhibits Homologous Recombination Repair By Targeting Rad51 Paralogs In Human Lung Fibroblasts., Aggie R. Williams

Electronic Theses and Dissertations

Hexavalent Chromium [Cr(VI)] is a known human lung carcinogen and general health hazard. The mechanism of carcinogenesis remains poorly understood, but chromosome instability (CIN) is the major theory in its carcinogenic mechanism. Homologous recombination (HR) repair is a DNA repair pathway that prevents CIN by repairing DNA double-strand breaks. RAD51, a key mediator protein of HR repair, along with the RAD51 paralogs (RAD51B, C, D, XRCC2, and 3) are required for HR repair. During HR, RAD51 loads and forms a helical nucleoprotein filament structure to promote DNA strand exchange and stimulate pairing activity of DNA. Cr(VI) exposures have been shown …

Behavioral Effects And Neurobiological Mechanisms Of 3-Aminobenzimide In A Rodent Model Of Chronic Psychological Stress, Liza Wills

Electronic Theses and Dissertations

Major depressive disorder (MDD) is a leading cause of disability worldwide, with a lifetime prevalence rate of approximately 20%. Inadequate pharmacological treatment methods for MDD are a significant debilitating factor. Patient estimates suggest that the treatment resistance rate for pharmacological interventions is over 30%. Postmortem analyses of human tissue of individuals diagnosed with MDD have shown an increase in Poly (ADP-ribose) polymerase 1 (PARP-1) mRNA gene expression in prefrontal cortical white matter when compared to psychiatrically normal brain tissue. In order to further investigate this issue, the present study used the social defeat stress/chronic unpredictable stress (SDS + CUS) rodent …

Characterizing The Role Of Macrophages In Cisplatin-Induced Kidney Injury And Progression To Chronic Kidney Disease., Sophia M. Sears

Electronic Theses and Dissertations

Cisplatin is a commonly used chemotherapeutic for treatment of many solid-organ cancers. Unfortunately, 30% of patients treated with cisplatin develop acute kidney injury (AKI), and even patients who do not develop AKI are at risk for long term declines in kidney function and development of chronic kidney disease (CKD). While traditional rodent toxicity studies have utilized a single, lethal dose of cisplatin, new models of cisplatin-induced kidney injury have revealed that repeated, low doses of cisplatin lead to development of kidney fibrosis. This model can be used to examine AKI-to-CKD transition processes. C57BL/6 mice are one of the most used …

The Role Of Sphingolipids In Aki And The Progression To Ckd: Potential Therapuetic Targets., Nicholas A. Hoffman

Electronic Theses and Dissertations

Acute Kidney Injury (AKI) is most simply defined as a rapid decline in kidney function over a period of hours to days. There is currently a lack of effective treatment options for patients with AKI, highlighting the need to identify new therapeutic targets. Sphingolipids play a number of roles in different models of AKI, suggesting they could be promising future targets for treating kidney injury. Specifically, sphingosine-1-phosphate (S1P) and its receptors (S1PRs) have been implicated in numerous inflammatory disorders and models of AKI. The purpose of this review is to better characterize the role of S1P receptors in models of …

Isolation, Structure Elucidation, And Synthesis Of Natural Products From Marine Cyanobacteria, Keren Solomon

Electronic Theses and Dissertations

This thesis describes the isolation, structure elucidation, and synthesis of natural products from marine cyanobacteria. A crude extract from a cyanobacterium collected in Curacao showed selective affinity for the dopamine D₅ receptor in a screen against a panel of CNS receptors. Due to the high similarity of the D₅ and D₁ receptor, to date there are no known ligands that differentiate them. Attempts to purify the compound responsible for this affinity led to the isolation of the known compound caylobolide A. A second extract from a cyanobacterium collected in Panama underwent bioassay-guided fractionation and yielded the novel …

N-Acetyltranserase 2 (Nat2) Genotype Polymorphism In Cryopreserved Human Hepatocytes And Chinese Hamster Ovary (Cho) Cells., Mariam Refaat Zaky Habil

Electronic Theses and Dissertations

Arylamine N-acetyltransferases, NAT1 and NAT2, catalyze the detoxification and/or activation of drugs and aromatic amine carcinogens. Single nucleotide polymorphisms or SNPs result in different human NAT2 genotypes thus dividing the population into rapid, intermediate, and slow acetylators. We hypothesize allelic variants of NAT2 genotype will decrease levels of N-acetylation, cytotoxicity, oxidative stress, DNA adduct formation, and mutagenesis compared to the reference allele NAT2*4. Cryopreserved human hepatocytes expressing different NAT2 genotypes and NER-deficient Chinese hamster ovary (CHO) cells transfected with human CYP1A2 and human NAT2*4, NAT2*5B or NAT2*7B have been used to investigate N-acetylation of different xenobiotics. In …

Human Genetics, Psychotropic Drugs, And Acts Of Violence, Selma Jolanda Eikelenboom-Schieveld

Electronic Theses and Dissertations

From the start of the use of psychoactive prescription medications in the 1950s, physicians reported paradoxical adverse reactions, ranging from newly developing depressions to an increase in existing mood disorders, and extremely violent and bizarre acts of suicide and homicide. In this research, it is hypothesized that the pharmacological properties of the prescribed drugs or the interaction between the drugs and the enzymes that are primarily responsible for their metabolism (cytochrome P450s) could cause these reactions. Given that acts of violence could be medication-induced, the role of the rate of drug metabolism is discussed. Genetic testing of certain CYP450s could …

Dual Inhibition Of The Pi3k/Akt And Mek5/Erk5 Pathways For The Treatment Of Breast Cancer, Thomas Douglas Wright

Electronic Theses and Dissertations

Breast cancer is a heterogeneous disease state with several challenging frontiers. In particular, aberrations in the Phosphoinositide-3-kinase (PI3K) and Mitogen Activated Protein Kinase (MAPK) pathways have been linked to increased breast cancer proliferation and survival. It has been proposed that these survival characteristics are enhanced through compensatory signaling and crosstalk mechanisms. New evidence suggests that MEK5/ERK5, a member of the MAPK family, is a crucial component in the proliferation and survival of several aggressive cancers. We hypothesize that inhibiting both PI3K/Akt and MEK5/ERK5 pathways will decrease cell viability while maintaining limited collateral toxicity. In this study, we examined the effects …

Development Of A Lectin-Fc Fusion Protein With Antiviral And Anti-Cancer Activity., Matthew William Dent

Electronic Theses and Dissertations

This thesis describes the development of a novel lectin-Fc fusion protein and its antiviral and anti-cancer activity. The molecule, Avaren-Fc (AvFc), is a fusion of a variant of the actinomycete lectin actinohivin (Avaren) and the Fc region of human IgG1, and is selective for the terminal α1,2-mannose residues found at the ends of high-mannose-type glycans that can be found on the surface of certain heavily glycosylated viruses and cancer cells. Here, AvFc was found to be able to neutralize simian immunodeficiency virus as well as Hepatitis C virus with nanomolar IC₅₀ values. Furthermore, AvFc recognizes a number of cell …

Paraoxonase 2 Is Critical For Non-Small Cell Lung Carcinoma Proliferation., Aaron Whitt

Electronic Theses and Dissertations

Non-small cell lung carcinoma (NSCLC) comprises 85% of lung cancer diagnoses and is plagued by drug resistance. Thus, elucidating the underlying mechanisms of NSCLC is paramount to expand future treatment options. Paraoxonase 2 (PON2), an intracellular enzyme with arylesterase and lactonase functions, has well-established anti-atherosclerotic activity. Recent studies show PON2 is overexpressed in a variety of tumors and confers drug resistance, although these interactions have not been thoroughly examined in NSCLC. Thus, we sought to investigate the role of PON2 in cellular proliferation using PON2-knockout mice, primary mouse cells, and NSCLC cell lines. Using these approaches, we demonstrate that PON2 …

Development Of Bar-Peptide Nanoparticles And Electrospun Fibers For The Prevention And Treatment Of Oral Biofilms., Mohamed Yehia Mahmoud

Electronic Theses and Dissertations

Background: Periodontal diseases are globally prevalent inflammatory disorders that affect ~47% of U.S adults. Porphyromonas gingivalis (Pg) has been identified as a “keystone” pathogen that disrupts host-microbe homeostasis and contributes to the initiation and progression of periodontitis. Pg associates with oral streptococci in supragingival plaque and this interaction represents a potential target for therapeutic intervention. Previously our group developed a peptide (designated BAR), that potently inhibits Pg/Streptococcus gordonii (Sg) adherence in vitro and Pg virulence in a murine model of periodontitis. While efficacious, BAR (SspB Adherence Region) provided transient inhibition and required higher concentrations of BAR to disrupt established …

A Mechanistic Study Of The Teratogenic Potential Of 4-O-Methylhonokiol (Mh) On Japanese Medaka (Oryzias Latipes), Santu Kumar Singha

Electronic Theses and Dissertations

An additional goal of this project was to characterize the Wnt/β-catenin signaling pathway to unravel the adverse potential of MH on the cardiovascular system (CVS). Our study suggested that MH-mediated cardiovascular injury may be caused due to upregulation of some major components of the Wnt/β-catenin pathway through expression of excessive pro-inflammatory mediators. Moreover MH decreased expression of ErbB3 and NRG-2 suggesting impaired cardiac structure. MH exposure caused a slow heartbeat blood occlusion absence of blood circulation decreased hatching efficiency and increased mortality in medaka embryos in a concentration- and time-dependent manner. MH might cause blood vessel occlusion by increasing the …

Safety Assessment And Chemical Fingerprint Analysis Of Medicinal Plants Commonly Consumed As Herbal Teas; Rooibos (Aspalathus Linearis) And Moringa (Moringa Oleifera), Omer I. Fantoukh

Electronic Theses and Dissertations

The first chapter discusses the significance of natural products, safety challenges, and quality issues concisely. Specifically, the impact of herb-drug interaction on consumers and the quest for chemical markers for chemical fingerprinting development are provided. Rooibos tea (Aspalathus linearis) is a popular South African herbal tea enjoyed worldwide. Limited reports indicate the potential of rooibos tea to alter the activity of CYP450 isozymes. In chapter two, the phytochemical investigation of A. linearis resulted in the isolation and characterization of 14 phenolic compounds. Safety assessment of the phytochemicals through interaction with CYP, PXR, and P gp was conducted. The …

Continuous Production Of Raloxifene Hydrochloride Loaded Nanostructured Lipid Carriers Using Hot-Melt Extrusion Technology, Derick Muhindo

Electronic Theses and Dissertations

The aim of this study was to utilize a continuous process for the production of Raloxifene Hydrochloride (RX-HCl) loaded NLC formulations for extended drug release using hot-melt extrusion technology coupled with probe sonication, and also to evaluate the in vitro characteristics of the prepared NLCs by particle size, PDI, zeta potential, entrapment efficiency, drug loading, and in vitro drug release profile. Preparation of the NLCs using HME technology involved two main steps, first formation of a pre-emulsion after extrusion and then size reduction of the pre-emulsion using probe sonication to obtain the NLCs. Process parameters for the extrusion process like …

Developing Zebrafish As An In Vivo Model To Screen Compounds For Anti-Cancer Activity In Human Breast Cancer, Trisha Dhawan

Electronic Theses and Dissertations

Breast Cancer (BC) is the most frequently diagnosed cancer; 1:8 women are at risk of developing BC in her lifetime. Cancer metastasis causes the majority of deaths in BC patients. Moreover, side effects of traditional chemotherapeutic drugs (TCD) impair the quality of life of these patients. Discovery and development of safe and effective new therapies is imperative for the treatment of BC and targeting metastasis. The goal herein is to further expand the applicability of in vivo xenotransplantation of human BC cells in transgenic zebrafish to screen potential chemotherapeutics for toxicity and efficacy. For xenotransplantation, MCF-7, BT-474, and MDA-MB-231 BC …

Implementing Mass Spectrometry For The Structural And Compositional Analysis Of Proteins, Mohammad Riaz

Electronic Theses and Dissertations

Lectins are sugar-binding proteins that perform various biological functions such as cellular recognition attachments etc. Pulses the dried edible seeds of certain plants are great sources of lectins and a proteomics approach directed at lectins identification would bring substantial improvement in the lectin identification process. Lectins from nine different plant species were analyzed through SDS-PAGE and proteomics analysis. After LC-MS/MS analysis proteins were identified with protein database searches using Uniprot. Functionally uncharacterized proteins were identified with database searches were annotated with the Pfam and NCBI-CCD databases. In-vitro pharmacological screening will be carried out to assess the pharmacological effects of these …

Pharmacokinetic Study Of Novel Anthraquinone Analogues, Yuhan Guo

Electronic Theses and Dissertations

Small molecules functioning as negative regulators of MDM2 have been considered as promising anti-cancer agents. A series of novel anthraquinone (AQ) analogues upregulate p53, a well-known tumor suppressor, by inactivating its antagonist protein MDM2. The novel AQ compounds synthesized through the modifications on the rhein scaffold were reported to have successfully arrested tumor growth. To have a better understanding of their underlying metabolism in vivo, pharmacokinetic (PK) studies were performed for the AQ compounds. A selective, accurate and reproducible assay methodology for PK study was set up for each AQ compound. The stabilities of AQ compounds were then evaluated …