Pharmacology, Toxicology and Environmental Health Commons^™

The Characterization Of Per- And Polyfluoroalkyl Substances (Pfas) In Nebraska Drinking Water And Human Health Impacts, Sarah Tucker

Theses & Dissertations

Per- and polyfluoroalkyl substances (PFAS) are synthetic compounds that have been detected in water sources of urban and rural environments with evidence of adverse human health effects from exposure. Humans are primarily exposed through ingestion of contaminated water and food. PFAS exposure has been linked to negative multi-system health outcomes (liver, kidneys, cardiovascular, reproductive, and immune). PFAS occur as persistent mixtures in environmental media with decades long consequences to water quality. While national agencies have launched large-scale PFAS water quality monitoring studies, limited data exists for contamination of rural water in Nebraska, especially private wells. The aims of this study …

Ccr5-Ligand Decorated Rilpivirine Lipid-Based Nanoparticles For Sustained Antiretroviral Responses, Milankumar Patel

Theses & Dissertations

Antiretroviral therapy (ART) is the standard remedy to improve the health-related quality of life of people living with human immunodeficiency virus (HIV). However, limited access to the viral reservoir has significantly hindered its effectiveness in fully eradicating HIV. Therefore, to improve HIV therapy, here we propose a C-C chemokine receptor type 5 (CCR5)-targeted theranostic lipid Based Nanoparticles (LBNPs) to noninvasively track and specifically deliver the antiretroviral drugs (ARVs) to the viral reservoir. A multi-modular radioactive nanoprobe was synthesized and co-encapsulated with rilpivirine (RPV, an ARV) into the LBNP to achieve a theranostic LBNP that can be tracked by positron emission …

Pharmacokinetics And Tissue Distribution Of A Lipid-Based Extended-Release Nano-Formulation Of Mo-Oh-Nap Tropolone To Enhance Pulmonary Delivery For The Treatment Of Pulmonary Metastatic Osteosarcoma, Wafaa N. Aldhafiri

Theses & Dissertations

Osteosarcoma is the most common primary bone tumor in children and adolescents. Metastasis is prevalent in 25% of patients, at diagnosis, with the lungs being the most common metastatic site. Pulmonary metastatic osteosarcoma is a significant therapeutic challenge with a 5-year survival rate of ≤30%. Patients with pulmonary metastatic disease at diagnosis receive the same standard of care as patients with local disease, which hasn’t changed over the past 30 years. The treatment and prevention of pulmonary metastatic osteosarcoma represents a significant critical and unmet need.

MO-OH-Nap tropolone is a novel small molecule with cytotoxic activity across multiple human osteosarcoma …

Development Of Long-Acting Antiviral And Antimicrobial Prodrug Nanoformulations, Srijanee Das

Theses & Dissertations

Over the past decade, the global burden of infectious diseases has increased substantively, underscoring the need for more effective treatment strategies. However, the discovery and development of new drugs with desirable safety, pharmacokinetics, and efficacy is a time consuming and costly process with great uncertainty around success rate. As an alternative to new drug development, prodrugs and novel drug delivery systems have increasingly been explored. Both serve to overcome the drug development challenges. Such drug formulations that permit extended dosing intervals of potent native drugs serve multiple purposes by promoting patient adherence to in improving treatment outcomes. This is especially …

Pharmacodynamic Effects Of Zsj-0228 On Complement Protein Deposition In The Kidneys Of Focal Segmental Glomerulosclerosis-Afflicted Mice., Braeden Pinkerton

Theses & Dissertations

Chronic inflammation, when left untreated, may result in significant morbidity and in severe cases, mortality. While glucocorticoids (GCs) are still being extensively used clinically as a class of very potent anti-inflammatory agents, they are also notorious for diverse adverse side effects. To mitigate these side effects, we have developed a polyethylene glycol (PEG)-based prodrug (ZSJ-0228) of dexamethasone (Dex). When tested on rodent models of Lupus Nephritis and Focal Segmental Glomerulosclerosis (FSGS), ZSJ-0228 was found to provide potent and sustained therapeutic efficacy without any detectable typical GC-associated side effects. Given ZSJ-0228’s transient renal exposure after systemic administration, it is yet to …

Assessment Of In-Vitro And In-Vivo Pre-Clinical Pharmacokinetics Of Epz015666; A Novel Small Molecule For Medulloblastoma Treatment, Pratiksha U. Kshirsagar

Theses & Dissertations

Group 3 medulloblastoma (MB) has the worst prognosis of the MB subgroups associated with elevated MYC expression and a 5-year survival rate of

Quantitation of EPZ was performed on a Shimadzu LC-MS/MS system utilizing electrospray ionization operated in positive mode. The validated assay was linear from 0.2 to 500 ng/mL. Metabolic stability studies demonstrated slow intrinsic clearance of EPZ in mouse and human liver microsomes, suggesting no CYP-mediated metabolism. Additionally, EPZ exhibited low binding affinity to plasma and brain proteins and high apparent permeability across artificial membranes, indicating efficient membrane penetration. Drug transporter studies identified EPZ as a substrate of …

An Ultra Long-Acting Bictegravir Prodrug Nanocrystal With A Shape-Shifting Pharmacokinetic Tail, Mohammad Ullah Nayan

Theses & Dissertations

While antiretroviral therapy (ART) has significantly reduced human immunodeficiency virus type one (HIV-1) co-morbidities and mortality, adherence to daily oral therapy remains a key barrier to all therapeutic and preventative outcomes. Over the past years, the emergence of long-acting (LA) ART has gained considerable enthusiasm amongst people living with HIV (PLWH) and could potentially simplify dosing regimens and improve treatment outcomes. LA ART could also improve drug adherence, reduce viral transmission, and limit viral drug resistance and systemic toxicities. In response to these needs, a combination of two LA injectable nanocrystalline drugs (CABENUVA) was recently approved for bimonthly administration in …

Intramuscular Administration Of The Host-Derived Immunostimulant Cpdi-02 Increases Protection Of Outbred Mice And Piglets Against Dermal Mrsa Infection In A Curative Setting And Is Well Tolerated After Repeated Administration, Jason P. Stewart

Theses & Dissertations

Staphylococcus aureus is the most common cause of bacterial skin and soft tissue infections (SSTIs) and the leading cause of hospital-associated infections in the United States. The abundance of S. aureus infections is due, in part, to its virulence factors that suppress host immune system and the development of antibiotic resistance strains such as methicillin-resistant S. aureus (MRSA). In contrast to antibiotics, Host-Directed Therapeutics (HDTs), avoid the pitfalls of antibiotics by targeting the host for immune system rather than targeting the pathogen. This mechanism of action avoids selective evolutionary pressure, which leads to antibiotic resistance and helps the host immune …

Hepatocyte-Hepatic Stellate Cell Axis In Potentiation Of Alcohol And Hiv-Induced Liver Injury, Moses O. New-Aaron

Theses & Dissertations

Human Immunodeficiency Virus (HIV) remains a global threat, with approximately 38.4 million active infections and 33 million HIV-related deaths since the first case. While many may be tempted to think of HIV as a relic of the past, emerging data suggests otherwise. By the end of 2021, approximately 1.5 million HIV incidences and 650 000 mortalities were reported globally. The etiologies of HIV-related mortality are numerous. Liver disease is one of the leading etiologies of HIV-related mortality, especially in recent times of antiretroviral therapy (ART)-induced longevity among people living with HIV (PLWH). While co-infections with hepatotropic viruses notoriously contribute to …

Nanofabrication For Precision Vaccinology, Karen Zagorski

Theses & Dissertations

Vaccines are among the most effective and safe therapeutics known to mankind. Historically the approach to the creation of new vaccines has been dominated by empirical research, trial, and error. This thesis focuses on the more modern, rational approaches to vaccinology based on the current understanding of the inner workings of the immune system. We used nanotechnology for the generation of novel immunogens, addressed several challenges, and characterized the immune responses.

The preparation, characterization, and troubleshooting of several vaccines against dimeric amyloid beta are covered in chapters 4-6. Despite being ultimately unsuccessful, this part provided a deeper understanding of the …

Neuropilin-2 In Advanced Prostate Cancer And Its Targeting With Novel Small Molecule Inhibitors, Ridwan Islam

Theses & Dissertations

Despite the development of new therapies, clinical management of advanced metastatic castrationresistant prostate cancer (mCRPC) still remains challenging owing to the emergence of therapy resistance. Resistance to the therapies is driven by both AR and non-AR pathways. Non-AR pathway is characterized by a lineage switch that leads to the development of neuroendocrine-like (NE-like) prostate cancer (PCa), which has a fulminant clinical course due to the lack of effective treatment strategy. Therefore, novel molecular targets need to be identified to develop effective therapeutic regimen to improve the outcomes in advanced PCa patients including NE-like PCa. Recent investigation on advanced PCa patients …

Polymeric Nanocarriers For Delivery Of Small Molecules Inhibiting Tubulin Polymerization For The Treatment Of Pancreatic Cancer And Lung Metastatic Melanoma, Rajan Sharma Bhattarai

Theses & Dissertations

The aim of this thesis is to develop delivery systems for the novel small molecules which inhibit tubulin polymerization. One of the small molecules was modified to lipid conjugate to increase the lipophilicity of the molecules which in turn drastically improved the drug loading in amphiphilic polymeric system. The second molecule was conjugated to the amphiphilic polymeric backbone with pH sensitive Schiff’s linker for the tumor site specific delivery in lung metastatic melanoma model.

Chapter 1 discusses the tumor microenvironment for the solid tumor especially focusing on Pancreatic Ductal Adenocarcinoma (PDAC). Further the drug delivery system currently researched for addressing …

Utilizing Proteolysis-Targeting Chimeras To Target The Transcriptional Cyclin-Dependent Kinases 9 And 12, Hannah King

Theses & Dissertations

Cyclin-dependent kinases (CDKs) are a family of serine-threonine kinases involved in various cellular functions, such as regulating the cell cycle and gene transcription. CDK9, a transcriptional CDK, regulates highly expressed enhancer-associated oncogenic transcription factors, including the oncogene Myc. CDK9 is responsible for the transcription and stabilization of Myc; consequently, it was a validated target for pancreatic cancer treatment.

As such, we developed a panel of aminopyrazole based proteolysis targeting chimera where we identified PROTAC 2 as a selective degrader of CDK9 (DC₅₀ = 158 ± 6 nM). PROTAC 2 was capable of cereblon mediated proteasomal degradation of CDK9 while …

Development Of Long-Acting Antiviral Drug Nanoformulations, Denise Cobb

Theses & Dissertations

Antiretroviral therapy (ART) has improved the quality and duration of life for people living with human immunodeficiency virus (HIV) infection. However, opportunities to improve its profile abound. ART is limited by putative viral reservoir penetrance, emergence of viral mutations, inherent toxicities, and regimen non-adherence. These highlight the need improved drug delivery schemes. Previously, our lab has demonstrated that targeting mononuclear phagocytes for antiretroviral drug delivery extends drug half-life and improves penetrance into viral reservoirs, addressing these limitations of ART. Herein, we developed synthetic and biologic antiretroviral (ARV) drug nanocarriers improve the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of ARVs through …

Long-Acting Nanoformulated Antivirals For The Treatment And Prevention Of Hiv-1 And Hbv Infections, Dhruvkumar M. Soni Dr.

Theses & Dissertations

While antiretroviral therapy (ART) has revolutionized treatment and prevention of human immunodeficiency virus type one (HIV-1) infection, regimen adherence, viral mutations, drug toxicities, stigma and pill fatigue are limitations. These have led to the development of long acting (LA) ART. These include, but are not limited to, implantable devices, new chemical entities, prodrug modifications and nanoformulations. To these ends, this thesis focues on the transformation of nucleoside reverse transcriptase inhibitors (NRTIs) into LA parenterals, While elusive, data from our laboratories demonstrated that modifications to the PROdrug and nucleoTide technology (ProTide) enables improvements in drug apparent half-life and tissue and cell …

Next Generation Aryl Hydantoins As Antischistosomal Agents, Derek A. Leas

Theses & Dissertations

Schistosomiasis, also known as “snail fever,” is both an acute and chronic disease spread by trematode flukes from the tropical parasitic worm genus Schistosoma. The flukes are spread via diseased freshwater snails, which release the parasites into the water column where they find a new human host. According to the World Health Organization (WHO), 99 million people were treated for schistosomiasis in 2017. The primary treatment used to combat schistosomiasis is the drug praziquantel (PZQ), but due to high drug pressure and widespread administration, its effectiveness has eroded because of rising drug resistance. Furthermore, PZQ is active against adult but …

Development Of An Lc-Esi-Ms/Ms Method For Determination Of A Novel Pyrrolomycin (Mp-1) And Application To Pre-Clinical Adme Studies, Wafaa N. Aldhafiri

Theses & Dissertations

A rapid, selective, and sensitive liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitation of a novel Pyrrolomycin (MP-1) in mouse plasma. MP-1 was extracted from plasma utilizing a structural analog (PL-3) as the internal standard (IS). Analyte separation was achieved using a Waters Acquity UPLC®BEH C18 column (1.7 µm, 100 x 2.1 mm) protected with Acquity UPLC C18 guard column. Mobile phase consisted of 0.1% acetic acid in water (10%) and methanol (90%) at a total flow rate of 0.25 mL/min. The mass spectrometer was operated at unit resolution in the multiple reaction …

Delivery Of Small Molecule And Rna Using Synthetic Polymeric Micelles And Multifunctional Exosomes For The Treatment Of Type 1 Diabetes, Yang Peng

Theses & Dissertations

Type 1 diabetes is one of the most challenging chronic autoimmune diseases. The destruction and dysfunction of insulin-secreting β cells are the results of inflammatory infiltration and the synergistic effect of multiple immune cells. The aim of this dissertation is to develop novel and reliable therapeutic approaches to advance the treatment of T1D: including chemical modification of a broad-spectrum immunosuppressant, co-application of small molecule based immune intervention and siRNA based β cell preservative therapy, and administration of a PI3K-δ/γ dual inhibitor to specifically target immune cells, utilizing synthetic polymeric micelles or natural produced multi-functional exosomes derived from human bone marrow …

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 …

Computational Studies And Design Of Pparγ And Glut1 Inhibitors, Suliman Almahmoud

Theses & Dissertations

The peroxisome proliferator-activated receptor gamma (PPARγ) is a ligand-dependent transcription factor of the nuclear receptor superfamily that controls the expression of a variety of genes involved in fatty acid metabolism, adipogenesis, and insulin sensitivity. PPARγ is a target for insulin-sensitizing drugs, and it plays a significant function in prostate cancer. PPARγ antagonists have anti-proliferative effects in a broad range of hematopoietic and epithelial cell lines. The ligand binding domain (LBD) of PPARγ is large and has orthosteric and allosteric binding sites. Several PPARγ-ligand co-crystal structures show two bound molecules, one to the orthosteric pocket and a second to the allosteric …

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 …

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 …

Development Of Long-Acting Nanoformulated Abacavir Protides, Zhiyi Lin, Howard E. Gendelmant

Theses & Dissertations

Combination antiretroviral therapy (cART) for treatment of human immunodeficiency virus (HIV) infection demands life-long regimen adherence. Treatment interruptions lead to a lack of virologic control and the emergence of viral mutations and drug resistance. To address these, our laboratory developed long-acting (LA) parenteral administered nanoformulated abacavir prodrug (NMABC) by formulating myristoylated abacavir (MABC) with poloxamer 407 as stabilizer, which sustained ABC levels for up to 2 weeks with low levels of active drug metabolite (CBV-TP). To more significantly extend the apparent half-life of ABC and improve its antiretroviral activities, we developed second generation long-acting ABC prodrugs by ProTide technologies. This …

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 …

Modulation Of Estrogen Metabolism And Prevention Of Pathologies, Bodhisattwa Mondal

Theses & Dissertations

Estrogens have been implicated in non-cancerous pathologies such as Fuchs Endothelial Corneal Dystrophy (FECD), and accumulating evidence suggests estrogen genotoxicity leads to initiation of multiple types of cancer among Caucasian populations. These studies were mono-racial, and restoration of estrogen metabolism imbalance using naturally occurring compounds were not definitive. Therefore, the role of estrogen metabolism in FECD, in cancer initiation among African American (AA) populations, its modulation by environmental toxicant arsenic trioxide (As₂O₃), and by antioxidants polydatin (PD) and resveratrol were explored.

In human breast epithelial non-transformed MCF10A cells, As₂O₃ – induced cytotoxicity was …

Biotransformation Of Praziquantel By Cunninghamella Elegans, Umbelopsis Ramanniana, And Yarrowia Lipolytica Metabolism, Samuel Chivers

Theses & Dissertations

Schistosomiasis is a neglected tropical disease rampant in developing countries. Widespread chemotherapy is reliant on a single drug, praziquantel, which increases the risk of resistance and creates an urgent need for the development of new alternatives for treatment. Fungal biotransformation is a well-documented tool in the pharmaceutical synthesis of new drugs. This study examined the efficacy of four fungal strains, Cunninghamella elegans (ATCC 9245 and ATCC 8688a), Umbelopsis ramanniana, (ATCC 9628) and Yarrowia lipolytica (ATCC 20225), in the biotransformation of praziquantel. Colonies were cultured, dosed with praziquantel, incubated for 5, 10 or 15 days to metabolize, after which the …

Development Of Chloroquine-Containing Hpma Copolymers For Drug Delivery, Fei Yu

Theses & Dissertations

Abstract

Development of Chloroquine-containing HPMA Copolymers for Drug Delivery

Fei Yu, Ph.D.

University of Nebraska Medical Center, 2018

Supervisor: David Oupický, Ph.D.

Synthetic polymers have been extensively explored for improved delivery of anticancer agents. Polymers can be designed as either carriers of existing drugs or as polymeric drugs with intrinsic pharmacological activity. Advantages of such polymeric drugs include common positive features of polymer-drug conjugates, such as targeted delivery of drugs, altered pharmacokinetic and biodistribution, improved drug safety, but also favorable pharmacological activities due to multivalent receptor-ligand interactions.

Chloroquine (CQ) and hydroxychloroquine (HCQ) are safe drugs that have been in clinical …

The Opposing Roles Of Glun2c And Glun2d Nmda Receptor Subunits In Modulating Neuronal Oscillations, Zhihao Mao

Theses & Dissertations

N-methyl-D-aspartate receptors (NMDARs) are ligand-gated ion channels consisting of two GluN1 subunits and two other subunits from among GluN2A-2D and GluN3A-3B subunits. NMDARs play critical roles in synaptic plasticity, learning and memory, and higher brain function such as cognition and perception. Dysfunction of NMDARs (hyper-function and hypo-function of NMDARs) are related to various diseases, including stroke, schizophrenia, Alzheimer’s disease, and others. However, to date, NMDARs antagonists have mostly failed in clinical trials due to adverse effects.

NMDARs antagonists replicate the core symptoms of schizophrenia which may underlie its ability to alter neuronal oscillations in the neural circuitry of different brain …

Development Of Macromolecular Prodrug Conjugates For The Diagnosis And Treatment Of Musculoskeletal Diseases, Xin Wei

Theses & Dissertations

Macromolecular prodrug conjugate is a promising strategy for better diagnosis and treatment of musculoskeletal diseases. Our lab has pioneered this effort and has successfully developed multiple prodrug formulations. The general approach we have taken is to incorporate active ingredient (AI, including imaging probe or therapeutic agents) containing monomers into water-soluble and biocompatible polymers, such as N-(2-Hydroxypropyl) methacrylamide (HPMA) copolymers. Structural parameters of these polymeric prodrugs, such as molecular weight (MW), drug loading, prodrug activation mechanism and the selection of drug payload may greatly affect therapeutic efficacy and the safety of the macromolecular prodrugs. To investigate the impact of these …