Pharmacology, Toxicology and Environmental Health Commons^™

Theranostics For Antiretroviral Biodistribution And Pharmacokinetics, Brendan M. Ottemann

Theses & Dissertations

RATIONALE: Our laboratories birthed the field of human immunodeficiency virus (HIV) theranostics. The new field allows simultaneous detection (diagnostics) and treatment (therapeutic) for the identification, treatment and inevitable elimination of virus in cell and tissue compartments. By employing theranostics, antiretroviral drugs (ARVs) can be tracked in lymph nodes, gut, spleen and liver. Cellular viral reservoirs including CD4+ T cell populations and mononuclear phagocytes (MP; monocytes, macrophages, microglia and dendritic cells) along with subcellular endosomal structures can now be targeted for drug delivery bringing therapeutics to areas where virus replicates. The overarching idea rests in improving precision targeted ARV delivery. …

Role Of Astrocyte-Derived Extracellular Vesicles In Neuroinflammation Mediated By Drug Abuse, Ke Liao

Theses & Dissertations

Neuronal damage and neuroinflammation is a hallmark feature of HIV-associated neurological disorders (HANDs). Opioids abuse accelerates the incidence and progression of HAND; however, the mechanisms underlying the potentiation of neuropathogenesis by these drugs remain elusive. Extracellular vesicles (EVs) are essential conduits in HIV and drug abuse-mediated synaptodendritic injury and neuroinflammation. Findings from our group have demonstrated that astrocyte-derived EV (ADEV)-miRNA-29b mediates HIV Tat and morphine-induced neuronal injury, thus underscoring the importance of such interactions in NeuroHIV.

Besides, HIV Tat and morphine-mediated synaptodendritic injury via ADEVs, we are also interested in whether ADEVs contributes to neuroinflammation. Microglia are critical players in …

Excess No Stabilizes The Luminal Domain Of Stim2 In A Cys-Specific Manner Thereby Regulating Basal Calcium Homeostasis And Store-Operated Calcium Entry, Matthew Novello

Electronic Thesis and Dissertation Repository

Stromal-interaction molecule 2 (STIM2) is an endoplasmic reticulum (ER) membrane-inserted Ca²⁺-sensing protein which, together with the plasma membrane Ca²⁺ channel Orai1, regulates basal Ca²⁺ homeostasis and store-operated Ca²⁺ entry (SOCE). Recent evidence suggests that S-nitrosylation, which is the covalent attachment of a nitric oxide (NO) moiety to a cysteine thiol, can attenuate the function of the paralog STIM1 protein. Compared to STIM1, STIM2 also functions as a basal Ca²⁺ homeostatic feedback regulator. Therefore, the objective of my study was to evaluate the susceptibility of STIM2 to S-nitrosylation and the effects that this …

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 …

Investigation Of Riluzole’S Synaptic Protection Mechanism Through Hsf1-Bdnf Axis, Yi Zhang

Theses and Dissertations (ETD)

The FDA-approved amyotrophic lateral sclerosis (ALS) drug Riluzole has great potential in treating Alzheimer’s disease (AD) based on promising animal data as well as its known action on modulating synaptic transmission. However, its detailed mechanism of action is not fully understood. Here, we proposed work aiming to address this aspect via focus- ing on the Heat Shock Factor 1 (HSF1)-dependent mechanisms. We found that Riluzole could increase HSF1 and BDNF (Brain-Derived Neurotrophic Factor) expression both at transcriptional and translational levels. CA1 (Cornu Ammonia, the first region in the hip- pocampal circuit), is its main target. We also demonstrated a protective …

The Role Of Secretory Phospholipase A2 Group Iia In Obesity And Metabolism, Michael S. Kuefner

Theses and Dissertations (ETD)

Secretory phospholipase A2 group IIA (PLA2G2A) is a member of a family of secretory phospholipases previously implicated in inflammation, atherogenesis, and antibacterial actions. These enzymes hydrolyze glycerophospholipids at the sn-2 position releasing lysophospholipids and fatty acids. Though studies have shown PLA2G2A is pro-inflammatory and promotes atherosclerosis, no research has analyzed the role of this enzyme in obesity and metabolism. Studies in the past 5-10 years utilizing various knock- out or over-expression mouse models have analyzed the role of different secretory phospholipase A2s (sPLA2) in metabolic diseases. From these studies, it is known that at least seven of the 11 sPLA2 …

Pregestational Diabetes Induced Congenital Heart Defects And Coronary Artery Malformations; Mechanisms And Preventative Therapies, Anish Engineer

Electronic Thesis and Dissertation Repository

Congenital heart defects (CHDs) arise from perturbations in complex molecular and cellular processes underlying normal embryonic heart development. CHDs are the most common congenital malformation, occurring in 1 to 5% of live births, and are the leading cause of pediatric mortality. Adverse genetic and environmental factors can impede normal cardiogenesis and increase the likelihood of CHDs. Pregestational maternal diabetes increases the risk of CHDs in children by more than four-fold. As the prevalence of diabetes rapidly rises among women of childbearing age, there is a need to investigate the mechanisms and potential preventative strategies for these defects. The aim of …

Maternal Nicotine Exposure Induces Congenital Heart Defects In The Offspring Of Mice, Elizabeth Greco

Electronic Thesis and Dissertation Repository

Congenital heart defects are the most prevalent birth defect, and maternal cigarette smoking is a known risk factor. Nicotine replacement therapies are recommended to pregnant women who smoke to aid in smoking cessation, as this alternative is thought to be much safer compared to cigarette smoking. However, these products contain nicotine, and the safety of nicotine on the developing heart is not well known. In this thesis, a mouse model was used to test the hypothesis that maternal nicotine exposure (MNE) during pregnancy leads to congenital heart defects and coronary artery defects in the offspring of mice. MNE resulted in …

Reversal Of P-Glycoprotein And Breast Cancer Resistance Protein Mediated Multidrug Resistance In Vitro Using In Silico Identified Novel Compounds, Amila Nanayakkara

Biological Sciences Theses and Dissertations

Multidrug resistance (MDR) is a major cause of chemotherapy failure. Overexpression of ATP-binding cassette (ABC) transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are two well-studied drug transporters which are associated with MDR. These two transporters also act as a major functional unit of the blood brain barrier to protect the brain from xenobiotics and toxins. Lack of clinically approved P-gp and BCRP inhibitors renders chemotherapy treatments of many MDR cancers ineffective and obstructs drug uptake into the brain.

Using computational methods, we have identified new compounds that inhibit P-gp (Brewer et al., Mol. Pharmacol. 2014). Several of …

Reversal Of P-Glycoprotein And Breast Cancer Resistance Protein Mediated Multidrug Resistance In Vitro Using In Silico Identified Novel Compounds, Amila Nanayakkara

Biological Sciences Theses and Dissertations

Multidrug resistance (MDR) is a major cause of chemotherapy failure. Overexpression of ATP-binding cassette (ABC) transporters, P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) are two well-studied drug transporters which are associated with MDR. These two transporters also act as a major functional unit of the blood brain barrier to protect the brain from xenobiotics and toxins. Lack of clinically approved P-gp and BCRP inhibitors renders chemotherapy treatments of many MDR cancers ineffective and obstructs drug uptake into the brain.

Using computational methods, we have identified new compounds that inhibit P-gp (Brewer et al., Mol. Pharmacol. 2014). Several of …

Synthesis And Characterization Of A Long-Acting Emtricitabine Prodrug Nanoformulation, Ibrahim M. Ibrahim

Theses & Dissertations

The introduction of highly active antiretroviral therapy led to a paradigm shift in the management of HIV/AIDS changing a disease considered “a death sentence” to “a manageable chronic disease”. Nevertheless, challenges exist for successful treatment of HIV, including patient adherence to the complex daily regimens and the inability of current formulations to target viral sanctuaries. Introduction of nanoformulated antiretroviral therapy (ART) is a promising alternative to tackle these challenges. Our laboratory has been focusing on developing long-acting (LA) nanoformulated antiretrovirals and has succeeded in developing LA integrase inhibitors. However, challenges for this approach extend to a range of short-acting hydrophilic …

Novel Antiviral Effect Of A Small Molecule Onc201 And Its Potential Application In Hiv-1 Eradication, Runze Zhao

Theses & Dissertations

Despite the success of antiretroviral therapy (ART), eradication of HIV-1 from brain reservoirs remains elusive. HIV-1 brain reservoirs include perivascular macrophages that are behind the blood-brain barrier and difficult to access by ART. Macrophages express transcription factor FOXO3a and the TNF superfamily cytokine TRAIL, which are known to target HIV-1-infected macrophages for viral suppression. ONC201 is a novel and potent FOXO3a activator capable of inducing TRAIL. It can cross the blood-brain barrier, and has shown an antitumor effect in clinical trials. We hypothesized that activation of FOXO3a/TRAIL by ONC201 will reduce the size of HIV-1 brain reservoirs. Using primary human …

Development Of A Long-Acting Nanoformulation Of Dolutegravir For Prevention And Treatment Of Hiv-1 Infection, Brady Sillman

Theses & Dissertations

Dolutegravir (DTG) is a potent human immunodeficiency virus type 1 (HIV-1) integrase strand-transfer inhibitor (INSTI) with a high barrier to viral drug resistance. However, opportunities to improve its profile abound. These include extending the drug’s apparent half-life, increasing penetrance to “putative” viral reservoirs, and reducing inherent toxicities. These highlight, in part, the need for long-acting, slow effective release antiretroviral therapy (LASER ART) delivery schemes. A long-acting (LA) DTG was made by synthesizing a hydrophobic and lipophilic prodrug encased with poloxamer (P407) surfactant. This modified DTG (MDTG) reduced systemic metabolism and polarity, increased lipophilicity and membrane permeability, improved encapsulation, and formed …

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 …

Multimodality Somatostatin Analog For Fluorescence-Guided Surgery In Cancer, Servando Hernandez Vargas

Dissertations & Theses (Open Access)

Cancer surgery remains the primary curative treatment for most solid cancers and has major therapeutic implications for patients with neuroendocrine tumors (NETs). Anatomical and functional imaging technologies are widely used during the pre- and postoperative stages, but intraoperative disease recognition relies on direct visual inspection and the hands of surgeons. The limited number of clinical tools for real-time intraoperative visual feedback restricts the ability to remove the complete cancer source and is partially responsible for the high rate of disease recurrence in patients. Intraoperative imaging with fluorescent contrast agents has the potential to improve the ability of surgeons to detect …

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 …

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 …

Elucidation Of The Molecular Mechanisms Of Electrically-Induced Cardioprotection, Anne Elizabeth Roessler

Dissertations

Cardiovascular disease is the leading cause of death worldwide. A myocardial infarction (MI), commonly known as a heart attack, is a major event in cardiovascular disease characterized by reduced blood flow to the heart. The ischemia and reperfusion (I/R) injury associated with an MI results in a region of dead tissue in the heart called an infarct, the size of which influences patient prognosis. In the 1980s, it was discovered that short, non-lethal episodes of I/R, termed ischemic preconditioning (IPC), can protect the heart against a subsequent MI. Ischemic preconditioning demonstrated the phenomenon of endogenous cardioprotection. Cardioprotection has great potential …

The Role Of The Cell-Surface Protease Tmprss13 In Colorectal Cancer, Fausto Alexander Varela

Wayne State University Dissertations

Colorectal cancer (CRC) is one of the most common and deadly cancers in both men and women in the United States. Extracellular proteolysis is often dysregulated in cancer including (CRC), resulting in degradation of extracellular matrix, as well as cleavage, processing, or shedding of cell adhesion molecules, growth factors, and cytokines. Several members of the type II transmembrane serine protease (TTSP) family have been shown to play critical roles in cancer progression; however, many family members have not yet been characterized in malignancy. We identified TMPRSS13 transcript to be upregulated in CRC compared to normal colon. This increase was confirmed …

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 …

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 …

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 …

Characterization Of Cytosolic Sulfotransferase Expression And Regulation In Human Liver And Intestine, Sarah Talal Dubaisi

Wayne State University Dissertations

SULTs are conjugation enzymes that can modify the activity of a myriad of foreign and endogenous molecules. SULT expression was detected in various human tissues, including liver, small intestine, and colon. There are 13 human SULT genes that are classified into 4 families, SULT1, SULT2, SULT4, and SULT6. In humans, SULT1 and SULT2 families include 11 genes that are further divided into 6 subfamilies. In addition to their role in xenobiotic detoxification and regulation of physiological processes, SULT enzymes were implicated in the bioactivation of procarcinogens. Previous studies detected the expression of most SULT1 and SULT2 enzymes during early development, …

Medication Adherence For Foster Children From The Perspective Of Foster Care Providers, Odette Boyd

Walden Dissertations and Doctoral Studies

In 2015, over 427,000 children were in foster care and the largest population were in California's system. Of those children, more than 9,400 were prescribed psychotropic medications. Increases of psychotropic medication use have led to investigations and findings of medication oversights in foster care. Medication oversights included medication nonadherence, which was linked to an increase of problematic behaviors in foster children. The purpose of this phenomenological study was to explore the issues of medication adherence for foster care providers who care for foster children of mild to chronic health concerns who were prescribed medications and experienced multiple placements. By utilizing …

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 …

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 …

Effects Of A Heroin Conjugate Vaccine On The Antinociceptive And Abuse-Related Effects Of Heroin In Rats And Monkeys, Kathryn L. Schwienteck

Theses and Dissertations

The increase in heroin use is one factor contributing to the current opioid epidemic in the United States. There are three Food and Drug Administration (FDA) approved medications for the treatment of opioid use disorder (OUD), and these include agonist (i.e. methadone and buprenorphine) and antagonist (i.e. naltrexone) therapies. Although these medications are effective for some patients, regulatory constraints for agonist therapies limit access and patient compliance for naltrexone is poor. The development of new therapies, such as immunopharmacotherapies, for the treatment of OUD is a priority for the National Institute of Drug Abuse. A heroin immunopharmacotherapy, or vaccine, produces …

Development Of Mithramycin Analogues With Improved Efficacy And Reduced Toxicity For Treatment Of Ets-Dependent Tumors In Ewing Sarcoma And Prostate Cancer, Joseph Michael Eckenrode

Theses and Dissertations--Pharmacy

Introduction: Genetic rearrangements in Ewing sarcoma, prostate, and leukemia cells result in activation of oncogenic ETS transcription factor fusions. Mithramycin (MTM) has been identified as an inhibitor of EWS-FLI1 transcription factor, a gene fusion product responsible for oncogenesis in Ewing sarcoma. Despite preclinical success, a phase I/II clinical trial testing MTM therapy in refractory Ewing sarcoma was terminated. Liver and blood toxicities resulted in dose de-escalation and sub-therapeutic exposures. However, the promise of selectively targeting oncogenic ETS transcription factors like EWS-FLI1 prompted us to undertake the discovery of more selective, less toxic analogues of MTM. MTM is a potent inhibitor …

Understanding The Role Of Androgen Receptor Signaling In Modulating P38-Alpha Mitogen-Activated Protein Kinase In Experimental Autoimmune Encephalomyelitis, Grace Kathryn Voorhees

Graduate College Dissertations and Theses

Multiple Sclerosis (MS) is an inflammatory autoimmune disease of the central nervous system, characterized by axonal demyelination and multifocal inflammation. Like many autoimmune diseases, it is a sexually dimorphic disease, being 3-4 times more common in females than in males. p38α MAP kinase (MAPK) has an integral role in modulating inflammatory processes in autoimmunity. Conditionally ablating p38α MAPK in myeloid cells in B6 mice shows a sex difference in the animal model of MS, experimental autoimmune encephalomyelitis (EAE). In the absence of sex hormones, this sex difference was reversed, suggesting a role for sex hormones in modulating p38α MAPK signaling …

The Metabotropic Glutamate Receptor Mglur1 Regulates The Voltage-Gated Potassium Channel Kv1.2 Through Agonist-Dependent And Agonist-Independent Mechanisms, Sharath Chandra Madasu

Graduate College Dissertations and Theses

The voltage gated potassium channel Kv1.2 plays a key role in the central nervous system and mutations in Kv1.2 cause neurological disorders such as epilepsies and ataxias. In the cerebellum, regulation of Kv1.2 is coupled to learning and memory. We have previously shown that blocking Kv1.2 by infusing its specific inhibitor tityustoxin-kα (TsTX) into the lobulus simplex of the cerebellum facilitates eyeblink conditioning (EBC) and that EBC itself modulates Kv1.2 surface expression in cerebellar interneurons. The metabotropic glutamate receptor mGluR1 is required for EBC although the molecular mechanisms are not fully understood. Here we show that infusion of the mGluR1 …