Pharmaceutics and Drug Design Commons^™

Physiologically-Based Pharmacokinetic (Pbpk) Modeling For The Preclinical Development Of Spectinamide Antibiotics, Keyur R. Parmar

Theses and Dissertations (ETD)

Despite being an ancient disease caused by Mycobacterium tuberculosis (Mtb) and after decades of research, tuberculosis (TB) still affects millions of people every year worldwide. In 2018, the World Health Organization (WHO) reported that 10 million people developed tuberculosis and 1.5 million died of the disease. With the increase in the multidrug-resistant (MDR) and extensively drug-resistant (XDR) cases, the treatment for TB with the standard first and second-line therapy is becoming increasingly difficult. Therefore, there is an urgent need to find new anti-TB drugs as combination partners of existing and experimental classes of antimicrobial agents to shorten and simplify the …

Computer-Aided Drug Discovery For Helicobacter Pylori, Nicole Ann Vita

Theses and Dissertations (ETD)

Helicobacter pylori is a high-priority drug-resistant pathogen and is currently the only bacteria considered to be a class I carcinogen and there is a critical need to identify novel chemical matter to treat H. pylori infections. Hp is responsible for greater than 60% of gastric cancer related deaths and 89% of all gastric cancer morbidities. In a previous study, our lab identified novel Hp thienopyrmidine inhibitors that target respiratory complex I, an essential enzyme in respiration. Respiratory complex I is a large asymmetric multidomain and membrane bound enzyme and due to these innate features, it is not practical for biophysical …

Targeting Myeloid Protein Kinase C Signaling To Overcome Immune Suppression And Improve Immunotherapy In Cancer, Mehdi Chaib

Theses and Dissertations (ETD)

Checkpoint immunotherapy unleashes T cell antitumor potential which has revolutionized cancer treatment showing unprecedented long-term responses. However, most patients do not respond to immunotherapy which often correlates with a dysfunctional or immunosuppressive myeloid compartment. Immunosuppressive myeloid cells comprise Myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) and can suppress T cells via production of immunosuppressive factors. Conversely, efficient cytotoxic T cell priming is dependent on the ability of antigen-presenting cells (APCs), mainly conventional dendritic cells (cDCs) and macrophages, to present or cross-present tumor antigens to T cells. Thus, targeting immunosuppressive myeloid cells while simultaneously enhancing APCs represents a promising strategy …

Characterizing And Overcoming Resistance To Aminomethylspectinomycins In Gram-Negative Bacteria, Nisha Das

Theses and Dissertations (ETD)

Spectinomycin (SPC) is a broad-spectrum aminocyclitol antibiotic. Its use in agriculture has led to widespread resistance in enteric bacteria, necessitating the development of more effective analogs. Aminomethyl spectinomycins (amSPC) are modified spectinomycins with increased potency against many bacterial species. These species include Legionella pneumophila, which harbors a chromosomally encoded aminoglycoside modifying enzyme (AME). In this study, we follow up on this observation and examine the extent to which the amSPCs are substrates for AMEs through adenylation (ANTs) and phosphorylation (APH). APH(9)-Ia and ANT(3")(9) were expressed in E. coli BL21(DE3) and purified using the Ni-affinity chromatography. The ability of AMEs to …

Combating Hiv-1 By Targeting Drug Efflux Transporters On The Macrophage Reservoir, Ying Mu

Theses and Dissertations (ETD)

Introduction. HIV-1 eradication has not been achieved so far due to the existence of the cellular reservoir in which the virus can reside and replicate even under antiretroviral drug therapy (ART). Infected macrophages, which represent a long-term viral reservoir have been shown to lead to viral rebound independently. In response to the environmental stimuli, macrophages can be polarized into different phenotypes: the pro-inflammatory M1 and the anti-inflammatory M2. Tobacco smoking and alcohol drinking, which are prevalent among people who are living with HIV-1, have been shown to promote HIV-1 progression and decrease the efficacy of antiretroviral drugs. A commonly …

Model-Based Dose-Exposure-Response Assessment For Lead And Backup Spectinamide In A Mouse Model Of Tuberculosis, Santosh Janardan Wagh

Theses and Dissertations (ETD)

Despite decades of research, tuberculosis remains the oldest pathogen-based disease that is the leading cause of death from a single infectious agent. Among many anti-tubercular therapies under investigation, the semisynthetic compounds spectinamides are a promising novel class of anti-tuberculosis agents. One such lead candidate, spectinamide 1810, and backup spectinamide 1599 have demonstrated excellent efficacy, safety, and drug-like properties in various in vitro and in vivo assessments. The dose-ranging and dose fractionation studies were designed to characterize the dose-exposure-response relationship for lead and backup spectinamide in a mouse model of Mycobacterium tuberculosis infection. In this current study, we used 26 and …

Veru-111 As An Oral Tubulin Inhibitor Suppressing Triple-Negative Breast Cancer And Evaluation Of Novel Tubulin Inhibitors For Cancer Therapy, Shanshan Deng

Theses and Dissertations (ETD)

Triple negative breast cancer (TNBC) has aggressive clinical features strongly associated with poorer overall prognosis and higher mortality rates relative to other molecular subtypes. FDA-approved drugs, such as paclitaxel, are effective in treating TNBC. Yet, treatment failure is commonly observed due to the development of acquired chemoresistance, which remains a clinical challenge for TNBC therapy.

Validation And Application Of A Novel Target-Based Whole-Cell Screen To Identify Antifungal Compounds, Christian Alexander Dejarnette

Theses and Dissertations (ETD)

Traditional approaches to drug discovery are inefficient and have several key limitations that constrain our capacity to rapidly identify and develop novel experimental therapeutics. To address this, we have devised a second-generation target-based whole-cell screening assay based on the principles of competitive fitness, which can rapidly identify target-specific and physiologically-active compounds. Briefly, strains expressing high, intermediate, and low levels of a preselected target protein were constructed, tagged with spectrally distinct fluorescent proteins (FPs), and mixed together. The pooled strains were then grown in the presence of various small molecules, and the relative growth of each strain within the mixed culture …

Characterization Of Novel Cb2 Agonist Smm-295 And Its Effects In Ischemia/Reperfusion Injury, Jeffrey D. Pressly

Theses and Dissertations (ETD)

Acute kidney injury (AKI) is a major problem clinically affecting up to two-thirds of intensive care unit patients, and results in increased hospitalization time, the risk of developing chronic kidney disease, and mortality. Hallmarks of AKI include tubular cell death and a decrease in renal perfusion which leads to decreases in renal function following injury. For 20 years the pathophysiology of AKI has been well established. However, therapies for AKI have shown minimal to no success clinically. The work here describes our efforts to further categorize the effects of CB2 activation, a possible novel therapeutic target in AKI.

There is …

Tobacco/Hiv-1-Induced Myeloid Cell-Derived Extracellular Vesicles In Hiv-1 Pathogenesis, Sanjana Haque

Theses and Dissertations (ETD)

Introduction. Smoking, which is highly prevalent in people living with HIV/AIDS, has been shown to exacerbate HIV-1 replication, in part via cytochrome P450 (CYP)-induced oxidative stress. CYP enzymes metabolize cigarette smoke condensate (CSC), causing oxidative stress and cytotoxicity. Our previous studies have demonstrated that CSC and specific CSC constituents, benzo(a)pyrene and nicotine, potentially induce CYPs, resulting in higher oxidative stress and subsequent exacerbation of HIV-1 replication in monocytes and macrophages. However, the exact mechanism behind tobacco-induced, oxidative stress-mediated enhancement of HIV-1 replication is still poorly understood. Extracellular vesicles (EVs) have recently gained attention for their unique nature as intercellular messengers …

Development Of Multiple Microemulsion Eye Drops For Sustained Release Of New Glaucoma Drug, Doaa Nabih Ahmed Maria

Theses and Dissertations (ETD)

Persistent or repeated elevation of intraocular pressure (IOP) is a primary risk factor of visual field loss in glaucoma, therefore IOP reduction is the first-line therapeutic option in the disease management. Unfortunately, the current therapies are associated with a lot of deficiencies including several daily dosing, reduced efficacy and systemic side effects all of which resulted in poor patient compliance. Previously we have identified Calcium voltage-gated channel auxiliary subunit Alpha2delta 1 gene (Cacna2d1) as a novel modulator of IOP and confirmed that pregabalin targeted CACNA2D1 in eye tissues (ciliary body and trabecular meshwork) to lower IOP in a …

Genetic Exploration Of Hereditary Immune Diseases, Cheng Tian

Theses and Dissertations (ETD)

An autoimmune disease is a condition arising from an abnormal immune response to a normal body part. There are at least 80 types of autoimmune diseases, rheumatoid arthritis and systemic sclerosis are two of them. My study focuses on these two diseases. Our hypothesis is that mutated genes lead to autoimmune diseases that cause the immune system to attack the human body. The mutated genes cause the gene expression levels to change which fail to properly regulate the body's functions, resulting in immune system diseases. I used existing mouse models to improve the understanding of these two diseases.

The first …

Novel Determinants That Influence Azole Susceptibility In Candida Glabrata And Candida Albicans, Sarah Garland Whaley

Theses and Dissertations (ETD)

Despite the scientific and medical communities’ best efforts, the incidence of fungal infections in susceptible populations continues to rise. The most common cause of these opportunistic fungal infections is Candida. In fact, Candida is the fourth most common pathogen associated with nosocomial blood stream infections. Reported mortality rates for patients with candidemia vary, but have not decreased in the past fifteen years and are reported to be as high as 50%. Candida glabrata, second only to Candida albicans among Candida infections, expresses high rates of resistance to treatment with arguably the best class of currently available antifungals - …

Rheological Studies Of Injectable Thermoresponsive Biodegradable Hydrogels And Porcine Ocular Tissues, Chandana Reddy Damera

Theses and Dissertations (ETD)

This research has evaluated the rheological properties of two types of materials which include (i) semi-synthetic polymer-based injectable hydrogels [P(NIPAAm-co-DEX-Lactate HEMA) and P(NIPAAm-co-HA-AEMA)], and (ii) biological tissues (porcine ocular tissues).

A series of thermoresponsive and biodegradable in situ hydrogel based on N-isopropyacrylamide (NIPAAm) monomer and hydrolytically degradable oligolactate Dextran-lactate-HEMA or Hyaluronic acid (HA)-AEMA macromer were investigated as encapsulation matrices (scaffolds) for DPSCs/ADSCs and assess their applicability in dental/retinal tissue engineering. The rheological properties of the hydrogels were strongly dependent on the reaction conditions and composition of the hydrogels. Both the hydrogels exhibited linear viscoelasticity, and the values of storage moludus …

Discovery Of Novel Tubulin Inhibitors And Selective Survivin Inhibitors For Advanced Melanoma And Total Synthesis Of Bioactive 20s-Hydroxyvitamin D3, Qinghui Wang

Theses and Dissertations (ETD)

According to the statistics from American Cancer Society, the 5-year survival rate for patients with advanced melanoma is as low as 5%. Treatment of advanced melanoma, therefore, represents an unmet medical need. In this dissertation, I will show the effort to develop new generations of bioavailable tubulin inhibitors targeting the colchicine binding site and selective small-molecule survivin inhibitors for treating advanced melanoma. Extensive structure-activity relationship (SAR) studies of lead molecules ABI-231 and UC-112 have been performed.

Chapter 1 will introduce the current situation of advanced or metastatic melanoma, its clinical drug treatments, as well as problems in current drug treatments. …

Translational Pharmacokinetic-Pharmacodynamic Modeling And Simulation In The Development Of Spectinamides, A Novel Class Of Anti-Tuberculosis Agents, Chetan Rathi

Theses and Dissertations (ETD)

New chemotherapeutic agents are urgently needed to control the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of tuberculosis, which still remains an important public health challenge globally. Recently, spectinamides have emerged as a novel class of anti-tuberculosis agents that overcomethe native drug efflux. Spectinamides bind to the 30S bacterial ribosomal subunit which interferes with ribosomal translocation, and ultimately results in inhibition of protein synthesis. They have potent in vitro activity against drug resistant Mycobacterium tuberculosis (Mtb), and also demonstrated sustained efficacy in (Mtb)-infected mouse models. Pharmacokinetic (PK)/ pharmacodynamic (PD) analyses play a critical role in identifying …

The Development Of Methods To Account For Physiologic Dynamic Changes And Their Effects On The Pharmacokinetics Of Therapeutic Monoclonal Antibodies And Other Therapeutics, Josiah Thomas Ryman

Theses and Dissertations (ETD)

Physiologic changes in the body can drastically affect the clearance of a medication, and therefore increase the variability in exposure to the medication. Physiologic changes that can have a profound effect on the exposure of a medication can stem from changes CYP enzymes, transport proteins, binding protein expression, organ function, immune reactivity, and health status to name a few; with the focus of this dissertation on the dynamic changes in the ontogeny of MRP2 (an apical liver transport protein) and the dynamic changes caused by an immune response to a therapeutic monoclonal antibody (mAb). Several approaches can be used to …

Synthesis Of 20s-Hydroxyvitamin D3 Analogs And Their 1Α-Hydroxyl Derivatives As Potent Anti-Inflammatory Agents, Zongtao Lin

Theses and Dissertations (ETD)

Rheumatoid arthritis (RA) is one of the autoimmune diseases, and is affecting 2.5 million Americans in total. Among the treatment options of RA, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3] is the only steroidal drug used clinically for anti-inflammatory and immune diseases. However, long-term use of 1,25(OH)2D3 (625 µg/day) in human would result in hypercalcemia (toxicity), and 1,25(OH)2D3 has substantial hypercalcemic effects (toxicity) in mice at a dose as low as only 2 µg/kg. Fortunately, during the investigation of novel metabolic pathway of vitamin D3 by cytochrome P450 enzymes, we found 20S-hydroxyvitamin D3 [20S(OH)D3] as a good lead compound. 20S(OH)D3 suppressed disease symptoms at …

Age-Associated Expression Patterns Of Oatp 1b1 And Oatp 1b3 And Their Effect On The Disposition Of Fexofenadine, Margaret Mary Thomson

Theses and Dissertations (ETD)

As part of the drug disposition process (absorption, distribution, metabolism, excretion), an often overlooked aspect is transport. In order for drugs to be metabolized and excreted from the body they go through the liver or other drug removal organs. For drugs that are polar or are large they must rely upon transport mechanisms to transport them across the biomembranes of the drug removal organs. OATP1B1 and OATP1B3 are transporters on the sinusoidal membrane of the liver which work in concert with the drug metabolizing enzymes as part of the drug removal process. It is known that the development of each …

Biodegradable Polymeric Biomaterials In Different Forms For Long-Acting Contraception And Drug Delivery To The Eye And Brain, Dileep Reddy Janagam

Theses and Dissertations (ETD)

Efficacy of many of the new and existing therapeutics is often hampered by the lack of an effective and compliant method of delivery. Typically, drugs have poor water solubility, short half-lives, and low permeability across the biological membranes. The result is low bioavailability of the drugs at the target site and can cause toxicity and side effects at high doses. Often the conventional dosage forms fail to overcome these limitations. In the recent decades, biodegradable polymeric drug delivery systems have emerged as promising candidates to solve the challenges of poor solubility, low permeability and sustained release owing to the advantages …

Cannabinoid Receptor 2 (Cb2) Ligands Downregulate Pro-Inflammatory Markers In Stimulated Primary Human Periodontal Ligament Fibroblasts (Hpdlfs), Ammaar Hasan Abidi

Theses and Dissertations (ETD)

There are approximately 743 million individuals suffering from chronic periodontitis (PD) making it the sixth most prevalent condition worldwide. The affected adult population in the U.S. are nearly 64.7 million and the healthcare costs exceeds $14 billion. Recently, host response to pathogenic infection has been seen critical to the progression of PD and exhibit increase in various inflammatory markers. Marijuana is well known for its recreational usage and is a risk factor for periodontal disease, which is seen as a concern in society for its negative health consequences. However, many medical conditions can benefit from the pharmacological effects of cannabinoids. …

Discovery Of Natural Product-Based Antimycobacterial Agents Effective Against Non-Replicating Bacilli, Shajila Siricilla

Theses and Dissertations (ETD)

New antimycobacterial molecules that kill non-replicating Mycobacterium tuberculosis (Mtb) were identified by screening libraries of synthetic natural products. De novo screening of a 400-membered library of aurachin RE analogs resulted in discovery of UT-317 ((R)-20). UT-317 is a selective vitamin K2 biosynthesis (MenA) inhibitor that killed replicating and non-replicating Mtb at 2.31 μg/mL (MIC) and 0.85 μg/mL, respectively. A 50-membered library of capuramycin analogs was evaluated in their enzymatic inhibitory activities against translocase I (MraY/MurX) and prenyl-phosphate-GlcNAc-1-phosphate transferase (WecA). UT-01320 (45) is identified as a selective WecA inhibitor that kills both replicating and non-replicating Mtb at 1.50 μg/mL (MIC) and …

Biophysical And Biochemical Screening Approaches For Antimicrobial Drug Discovery Targeting S. Aureus Clpp, Aman Preet Singh

Theses and Dissertations (ETD)

The discovery of antibacterial drugs has been among most significant achievements of mankind in saving millions of lives across the planet from infectious diseases. With rise in resistance to almost all existing chemotypes, the design of next generation novel antibiotics has become much more challenging and difficult. The early 21st century witnessed the advancement of multiple novel chemotypes during golden age of antibiotics however the pace of antibiotic drug discovery has slowed down tremendously, contributing to life threatening antimicrobial discovery void since 1980’s. Therefore the need to develop novel antibiotics with unique mechanism of action to leverage against multi drug …

Discoveries Of Targets And Novel Agents For The Treatment Of Ischemic Retinopathy And Neovascular Disease, Jordan Javad Toutounchian

Theses and Dissertations (ETD)

Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are among the most common causes of blindness in adults. Vision loss can occur during the advanced stages of DR and AMD as a consequence of unregulated and dysfunctional growth of new blood vessels, or neovascularization (NV) in the retina or choroid. NV can also be triggered by numerous other ocular insults and diseases including radiation retinopathy (RR) and retinal vein occlusion. These latter cases are generally less common but, like DR and AMD, they are characterized by an initial injury, chronic inflammation, and ischemia which perpetuates episodes of retinal neovascularization (RNV). …

Hit Identification For Pkcζ Inhibitors: Structure-Based Optimization, Virtual Screening, And Biological Evaluation, Xiaoxin Wu

Theses and Dissertations (ETD)

Protein kinase C ζ (PKCζ) is believed to be a promising target for the treatment of some diseases, including inflammatory diseases, obesity and diabetes. Hit identification of PKCζ inhibitors was conducted by structure-based modification, virtual screening and biological evaluation. Among all the compounds selected and synthesized, compound JW-1-60A showed moderate activity against PKCζ at 30 μM and 100 μM. The molecular modeling studies showed that the binding mode of JW-1-61A was very close to the binding mode of JP-3-149, a reported PKCζ inhibitor with very potent activity, which might partially explain the moderate activity of JW-1-61A. Based on the structure …

Development Of Oral Vaccines Against Lyme Disease, Rita Raquel Dos Anjos De Carvalho E Melo

Theses and Dissertations (ETD)

Lyme Disease, caused by the spirochete Borrelia burgdorferi, is the most common vector-borne disease in the United States and Europe. If left untreated, it can lead to permanent damage to the nervous and musculoskeletal systems. In some cases, patients that receive the recommended antibiotic therapy develop a debilitating health condition associated with substantial health care costs. Despite current preventive measures, the incidence and the geographic distribution of Lyme Disease continues to increase. Recent estimates from CDC suggest that the true number of cases of Lyme Disease in the US is approximately 300,000 per year. Yet, there is currently no vaccine …

Optimization Of Lead Spectinamide Compounds As Novel Anti-Tuberculosis Agents With A Pharmacometric Approach, Ashit Rasendu Trivedi

Theses and Dissertations (ETD)

In an effort to combat the global Tuberculosis pandemic, Dr.Richard E. Lee and his group at St.Jude Children’s Research Hospital designed a novel series of anti-tuberculosis agents, spectinamides – semi-synthetic analogs of spectinomycin. Spectinamides are a potent inhibitor of mycobacterial ribosomes and overcome efflux mediated drug resistance in M. tb. Spectinamides have shown an excellent in vitro activity, which makes them well suited for further lead optimization and preclinical development. We hypothesized that through pharmacokinetic (PK) and pharmacodynamics (PD) model-based dosing optimization studies, we could strategically guide the selection and refinement of more potent and effective anti-TB spectinamides. Biopharmaceutical in …

Development And Evaluation Of Amphotericin B Loaded Iron Oxide Nanoparticles For Targeted Drug Delivery To Systemic Fungal Infections, Pavan Balabathula

Theses and Dissertations (ETD)

A targeted nanotheronostic drug delivery system to diagnose and treat life threatening invasive fungal infections (IFIs) such as cryptococcal meningitis was designed, developed, characterized, and evaluated. To address the development processes, first, iron oxide nanoparticles (IONP) (34-40 nm) coated with bovine serum albumin (BSA), loaded and targeted with amphotericin B (AMB) (AMB-IONP) was formulated by applying a layer by layer approach. Several designs (A, B, C, D, & E) of AMB-IONP were developed and their physicochemical properties such as drug loading with HPLC method, particle size, poly dispersity index (PDI), and ζ-potential using dynamic light scattering (DLS) technique, morphology with …

Discovery Of Novel Tubulin Polymerization Inhibitors And Survivin Inhibitors As Potential Anticancer Agents, Min Xiao

Theses and Dissertations (ETD)

Melanoma is the most dangerous form of skin cancer and accounts for the majority of skin cancer death. Although considerable advances have been made in melanoma treatment in recent years, there are many problems associated with current therapies. Drug resistance to targeted therapies is almost inevitable after short term treatment. Immunotherapies generally have low response rate and the effects vary among patients. Therefore, the need to develop new and more effective treatment for melanoma is high.

The work presented here focuses on discovery of novel anticancer agents for melanoma by targeting two important cancer targets: tubulin and survivin. Microtubules play …

Overcoming Acquired Resistance To Braf Inhibitors By Novel Synergistic Drug Combination And Discovery Of Novel Smac Mimetics As Selective Survivin Inhibitors, Jin Wang

Theses and Dissertations (ETD)

The first part (Chapter 1 and 2) of this dissertation presents a novel combination study of melanoma therapy. Acquired clinical resistance to vemurafenib, a selective BRAFV600E inhibitor, arises frequently after short term chemotherapy. Since the inhibitions of targets in the RAFMEK-ERK pathway result in G0/G1 cell cycle arrest, vemurafenib-resistant cancer cells are expected to escape this cell cycle arrest and progress to subsequent G2/M phase. We hypothesized that a combined therapy using vemurafenib with a G2/M phase blocking agent will trap resistant cells and overcome vemurafenib resistance. To test this hypothesis, we first determined the combination index (CI) values of …