Medicinal Chemistry and Pharmaceutics Commons^™

Absolute Quantification And Identification Of Rna From Rna-Lipid Nanoparticles Using High Resolution Mass Spectrometry, Jason C. Funderburk

Theses and Dissertations

RNA therapeutics are a rising drug category with potential use for a range of conditions encompassing infectious diseases to therapies for cancer, diseases, and genetic disorders. RNA-lipid nanoparticles (RNA-LNPs) are the prominent delivery method for these therapeutics approved products include mRNA vaccines and polyneuropathy treatments. The emergency use authorizations and orphan drug status of current RNA-LNP drugs has allowed approval without finalization of the regulatory analytical procedures for quality monitoring. The objective of the study was to develop an LC-MS assay to simultaneously measure identity and concentration of two therapeutically relevant intact RNA constructs extracted from RNA-LNPs to enhance quality …

The Impact Of Hiv-1 Tat And Morphine On Spatial Distribution Of Drugs In The Brain., Austin M. Jones

Theses and Dissertations

Despite combination antiretroviral therapy effectively suppressing HIV within the periphery, the central nervous system (CNS) remains affected by the virus. Approximately half of people living with HIV will experience HIV-associated neurocognitive disorders (HAND) or neuroHIV. Concurrent opioid use exacerbates neuroHIV by promoting neuroinflammation, viral replication, and potentially altering the antiretroviral concentrations within the brain.

Using a transgenic mouse that expresses the HIV-1 Tat protein, we examined the effects of Tat and morphine on antiretroviral accumulation and distribution and the effects of Tat on morphine accumulation within the brain using infrared matrix-assisted laser desorption electrospray ionization with mass spectrometry imaging (IR-MALDESI-MSI). …

Understanding Effect Of Ionic Liquid On Metalloproteins: Laccase And Azurin, Aashka Y. Patel

Theses and Dissertations

Interactions between ionic liquids and biomolecules have been of great interest due to the intrinsic properties of ionic liquids and the flexibility to mix and match cations and anions to create unique ionic liquids. A number of ionic liquid-biomolecule studies have focused on the interactions with proteins, including industrially relevant enzymes. One of these, laccase from Trametes versicolor, is a naturally derived enzyme used in the breakdown of phenolic compounds in a wide variety of industries, especially useful in breakdown of lignocellulosic materials. Here, a combination of experiments and molecular dynamics (MD) simulations were used to investigate the interactions …

An In Silico Study Of The Delta Opioid Receptor Using Small Molecules, Emily Dean

Theses and Dissertations

The DOR is the least studied out of the three opioid receptors (Mu, Kappa, and Delta). The most is known of the Mu Opioid receptor (MOR) and the drugs that target it have led to the global opioid epidemic due to their adverse effects of tolerance and addiction. The DOR is not known for the same adverse effects and therefore, is a promising pharmacological target for the development of new opioid ligands. In this thesis, molecular modeling, simulations and other computational methods are introduced in Chapter 1 where these methods are used to study the activation mechanism of DOR (Chapter …

Biomimetic Strategies To Control Therapeutic Release From Novel Dna Nanoparticles, Robert J. Mosley

Theses and Dissertations

The inherent chemical, mechanical, and structural properties of nucleic acids make them ideal candidates for the formulation of tunable, personalized drug nanocarriers. However, none so far have exploited these properties for the controlled release of therapeutic drugs. In this dissertation, a biomimetic approach to controlling drug release is exhibited by specifically manipulating the architecture of novel, DNA nanoparticles to take advantage of drug binding mechanisms of action. Rationally designed DNA strands were immobilized on gold surfaces via a terminal thiol modification. Immobilized monomers can be manipulated to form distinct monolayer architectures including flat, folded, coiled, or stretched structures. Increasing the …

Using Molecularly Imprinted Polymers For The Selective Extraction Of Analytes, Haley A. Mulder

Theses and Dissertations

Sample preparation is a critical steps in bioanalysis. Traditional methods such as solid-phase extraction and liquid-liquid extraction are laborious and ultimately incapable of properly separating target analytes from matrix and interferents. The co-extraction of these components interferes with the analytical instrument’s ability to properly detect and quantitate analytes. Molecularly imprinted polymers (MIPs) are synthetic polymers that have been “imprinted” with a template analyte in a co-polymer system. MIPs are capable of selectively extracting analytes from complex biological matrices and can be employed in off-line, benchtop extractions or for on/in-line instrument extractions. MIPs offer faster and more selective sample preparation, leading …

Nebulizer-Based Systems To Improve Pharmaceutical Aerosol Delivery To The Lungs, Benjamin M. Spence

Theses and Dissertations

Combining vibrating mesh nebulizers with additional new technologies leads to substantial improvements in pharmaceutical aerosol delivery to the lungs across therapeutic administration methods. In this dissertation, streamlined components, aerosol administration synchronization, and/or Excipient Enhanced Growth (EEG) technologies were utilized to develop and test several novel devices and aerosol delivery systems. The first focus of this work was to improve the poor delivery efficiency, e.g., 3.6% of nominal dose (Dugernier et al. 2017), of aerosolized medication administration to adult human subjects concurrent with high flow nasal cannula (HFNC) therapy, a form of continuous-flow non-invasive ventilation (NIV). The developed Low-Volume Mixer-Heater (LVMH) …

Pharmacophoric Evaluation Of 5-Ht2a And 5-Ht2b Serotonin Recpeptors, Prithvi Hemanth

Theses and Dissertations

Serotonin (5-HT) receptors represent a class of receptors involved in a variety of physiological processes including regulation of mood, perception, cognition, appetite, and heart function, and thus serve as drug targets of several drugs such as antipsychotic agents, hallucinogenic drugs, and appetite suppressant drugs. Due to the structural similarity of certain 5-HT receptor subtypes, particularly 5-HT₂ receptors (5-HT_2A, 5-HT_2B receptors) determination and refinement of pharmacophore models of these receptor subtypes can greatly improve the therapeutic efficacy of drugs that target them.

The goals of this study were to define and/or refine existing pharmacophore models for 5-HT …

Dendrimer-Based Antibiotics For The Treatment Of Bacterial Biofilm In Cystic Fibrosis (Cf), Younan Ma

Theses and Dissertations

Pseudomonas aeruginosa (PA) is the predominant pathogen in chronic lung infections of cystic fibrosis (CF) patients. The most important mechanism of adaptation of PA to host defense and antibiotic treatment is the formation of biofilms within the mucus layer covering the lung bronchi. The effectiveness of antibiotics such as aminoglycosides is significantly attenuated by their limited penetration through thick mucus and embedded biofilm matrix in patients’ lung. Inhaled tobramycin (Tobra), which is the most commonly used antibiotics in the treatment of PA infections for CF patients, is usually found to be in very high concentration in patients’ lung, and yet …

The Use Of Ultra-High Pressure Liquid Chromatography In High-Throughput Pharmaceutical Separations, Glenn Anthony Kresge

Theses and Dissertations

The higher pressures and flow rates needed to increase throughput in ultra-high pressure liquid chromatography (UHPLC) can lead to thermal broadening due to viscous friction. The use of superficially porous particles and still-air thermal environments can help reduce this broadening, which is especially important in applications requiring high-throughput, isocratic separations, such as monograph methods for over-the-counter analgesics. In the first experiment discussed below, system suitability parameters (resolution and peak asymmetry) and temperature changes across the axial length of the column were monitored at conditions near column or system pressure limits. Results from this investigation indicated that shorter columns packed with …

Pharmacology Of Fentanyl-Related Substances In Mice Reveals Potential Therapeutics With Improved Protective Indices, Neil B. Varshneya

Theses and Dissertations

Fentanyl-related substances constitute a class of compounds that were originally developed in the latter half of the 20th century as combination analgesic-anesthetic agents. Today, many of these compounds have emerged in the recreational drug marketplace as adulterants to heroin, counterfeit prescription pills, and even as standalone products designed to circumvent drug control laws. The objective of this dissertation was to identify the structural determinants of fentanyl analogs that could affect the potency and efficacy for eliciting their therapeutic and toxic effects to identify candidates of potential therapeutic interest. To accomplish this objective, thirty-eight fentanyl-related substances, in addition to the MOR …

Model-Based In-Vitro Pk/Pd Profiling Of Novel Synthetic Allosteric Effectors Of Hemoglobin (Aeh) As Potential Sickle Cell Disease (Scd) Therapeutics, Xiaomeng Xu

Theses and Dissertations

Introduction: Allosteric effectors of hemoglobin (AEH) represent a class of synthetic aromatic aldehydes that transiently form covalent interactions (Schiff-base) with hemoglobin (Hb) to form Hb-AEH adduct, preventing the HbS polymerization and sickling of red blood cells (RBC). The overall objective of this research was to aid in the optimization of novel AEH by understanding their target-site disposition of AEH in relevant biological matrices, e.g., HbA solution, whole blood (WB) and human liver cytosol (HLC), a surrogate of aldehyde dehydrogenase (ALDH)-mediated oxidative metabolism.

Methods: A “universal” HPLC-UV/Vis assay method was developed for the quantitation of HbA-AEH adduct for chemically …

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 …

5-Ht2b Receptor-Mediated Cardiac Valvulopathy, Pallavi Nistala

Theses and Dissertations

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

Salvianolic Acid B For Pulmonary Delivery Towards Reversal Of Emphysema, Sneha Dhapare

Theses and Dissertations

A new pathobiologic hypothesis has recently emerged that the alveolar structural destruction and loss in emphysema are caused by the deficiency of vascular endothelial growth factor (VEGF). Therefore, this project hypothesized that such pathobiologic VEGF deficiency of emphysematous lungs can be recovered with a natural caffeic acid tetramer, salvianolic acid B (SalB), through activation of signal transducer and activator of transcription 3 (STAT3), so that emphysema can be reversed as a result of inhibition of induced cell death, stimulation of cell proliferation and migration, and promotion of stem cell recruitment to the lungs.

SalB was first shown to be potently …

Three Dimensional Homology Modeling Of Organic Cation Transporter 3 To Identify Structural Elements Mediating Transporter-Substrate Interactions, Hebing Liu

Theses and Dissertations

Organic cation transporters (OCTs) play a pivotal role in the absorption, tissue distribution, and excretion of a diverse array of substances, and currently the nature of the biochemical interactions between substrate and OCTs are unknown. Therefore, identifying which amino acid residues are critical for OCT-substrate interactions is of central importance to understanding and predicting interactions between drugs and OCTs. A three-dimensional (3-D) homology model of human OCT3 was generated using the crystal structure of a high affinity phosphate transporter from Piriformospora indica (PiPT) as template, and putative binding pocket for the prototypical hOCT3 ligand 1-methyl-4-phenylpyridinium (MPP⁺) was identified …

Synthetic And Biological Exploration Of (+)-Boldine - Identification Of Potential Cns Receptor Ligands, Sujay Joseph

Theses and Dissertations

(+)-Boldine, an aporphine alkaloid, is reported to be biologically active at various Central Nervous System(CNS) receptors. However, only a few Structure Activity Relationship(SAR) studies have been conducted using boldine’s aporphine scaffold. A library of novel analogs was synthesized from boldine to understand the effect of bisbenzylation at C2 and C9 positions on the affinity and selectivity at the serotonin receptors.

High Affinity Block Of Icl,Swell By Thiol-Reactive Small Molecules, Sung H. Park

Theses and Dissertations

Ebselen (Ebs) is considered as a glutathione peroxidase (GPx) mimetic and primarily thought to function by scavenging intracellular reactive oxygen species (ROS). Previous to our work, Deng et al. (2010a) demonstrated complete block of I_Cl,swell with 15 microM Ebs following endothelin-1 (ET-1) induced activation of the current in cardiomyocytes. This block was presumed to take effect mainly via the quenching of ROS. Nonetheless, our work with DI TNC1 astrocytes strongly emphasizes that Ebs might function by an alternative mechanism based on its kinetic profile in blocking I_Cl,swell. Our experiments showed that 45 nM Ebs can fully block …

Development Of Non-Traditional Platinum Anticancer Agents: Trans-Platinum Planar Amine Compounds And Polynuclear Platinum Compounds, Daniel E. Lee

Theses and Dissertations

Development of Non-Traditional Platinum Anticancer Agents: trans-Platinum Planar Amine Compounds and Polynuclear Platinum Compounds

By Daniel E. Lee, Ph.D.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.

Virginia Commonwealth University, 2015

Major Director: Nicholas P Farrell, Ph.D., Professor, Department of Chemistry

Platinum anticancer compounds with cis geometry, similar to cisplatin, have been explored to circumvent the cisplatin resistance; however, they were not considered broadly active in cisplatin cells due to exhibiting similar or same cell death mechanism as cisplatin. Platinum compounds with trans geometry were less studied …

Elaboration And Design Of Α7 Nachr Negative Allosteric Modulators, Osama I. Alwassil

Theses and Dissertations

α7 Neuronal nicotinic acetylcholine receptors are one of two major classes of receptors responsible for cholinergic neurotransmission in the central nervous system. The existence of α7 neuronal nAChRs in different regions of the nervous system suggests their involvement in certain essential physiological functions as well as in disorders such as Alzheimer’s disease (AD), drug dependence, and depression. This project was aimed toward the discovery and development of small–molecule arylguanidines that modulate α7 nAChR function with improved subtype-selectivity through an allosteric approach. Identifying the required structural features of these small molecules allowed optimization of their negative allosteric modulator (NAM) actions at …

Development Of Irreversible Substrate Competitive Probes For Pka Activity, Robert A. Coover

Theses and Dissertations

The current environment for drug discovery and disease treatment relies heavily on genomic analysis, structural biology and chemical biology techniques. With the enormous advances in genomic analysis and structural biology, the use of and desire for targeted therapies has increased. However, as more genomic data for cancer disease state pathology becomes available we must ask increasingly difficult questions and even produce new technologies, such as activity-based probes, to answer these questions.

In particular, targeted kinase inhibitors for the treatment of cancer has become a mainstay for drug development for both industry and academia, but it is evident that the genomic …

Development Of Clinically Relevant In Vitro Performance Tests For Powder Inhalers, Xiangyin Wei

Theses and Dissertations

While realistic in vitro testing of dry powder inhalers (DPIs) can be used to establish in vitro–in vivo correlations (IVIVCs) and predict in vivo lung doses, the aerodynamic particle size distributions (APSDs) of those doses and their regional lung deposition remains unclear. Four studies were designed to improve testing centered on the behavior of Novolizer®. Different oropharyngeal geometries were assessed by testing different mouth-throat (MT) models across a realistic range of inhalation profiles (IPs) with Salbulin® Novolizer®. Small and large Virginia Commonwealth University (VCU) and Oropharyngeal Consortium (OPC) models produced similar ranges for total lung dose in vitro (TLD …

Novel Compounds As Potential Alzheimer's Disease Therapeutics And Inhibitors Of The Nlrp3 Inflammasome, Jeremy E. Chojnacki

Theses and Dissertations

Alzheimer’s disease is a devastating neurodegenerative disorder and the leading cause of dementia. The disease manifests via several pathologies including neuroinflammation, oxidative stress, metal ion dyshomeostasis, and cell death. To address the multifaceted nature of this disorder, the design of several diverse compounds, targeting many pathological effects, was generated. First, a series of compounds based on curcumin and diosgenin were synthesized following the bivalent design strategy. Two compounds were discovered to have neuroprotective ability, anti-oxidative function, and anti-Aß oligomerization (AßO) properties. A second set of molecules was also designed, wherein a hybrid compound strategy was utilized. Three hybrids were to …