Medical Pharmacology Commons^™

Genetic Dissection Of Quantitative Trait Loci For Substances Of Abuse, Jo Lynne Harenza

Theses and Dissertations

It has been reported that an individual’s initial level of response to a drug might be predictive of his or her future risk of becoming dependent, thus basal gene expression profiles underlying those drug responses may be informative for both predicting addiction susceptibility and determining targets for intervention. This dissertation research aims to elucidate genetic risk factors underlying acute alcohol and nicotine dependence phenotypes using mouse genetic models of addiction. Phenotyping, brain region-specific mRNA expression profiling, and genetic mapping of a recombinant inbred panel of over 25 mouse strains were performed in order to identify quantitative trait loci (QTL) harboring …

Identification And Characterization Of Ethanol Responsive Genes In Acute Ethanol Behaviors In Caenorhabditis Elegans, Joseph Alaimo

Theses and Dissertations

Alcohol abuse and dependence are complex disorders that are influenced by many genetic and environmental factors. Acute behavioral responses to ethanol have predictive value for determining an individual’s long-term susceptibility to alcohol abuse and dependence. These behavioral responses are strongly influenced by genetics. Here, we have explored the role of genetic influences on acute behavioral responses to ethanol using the nematode worm, Caenorhabditis elegans. First, we explored the role of ethanol metabolism in acute behavior responses to ethanol. Natural variation in human ethanol metabolism machinery is one of the most reported and reproducible associations found to alter drinking behavior. Ethanol …

Cytotoxic Properties Of Novel Platinum Compounds, Bbr3610-Dach And Trans-4-Nbd In Tumor Cells: Cellular Effects Of 1, 2-Dach And Nbd Ligands, Vijay Menon

Theses and Dissertations

Platinum-based chemotherapeutics are used for the treatment of a wide range of cancers and a number of attempts have been made toward developing compounds with better cellular stability and similar or enhanced cytotoxicity as compared to their predecessors. The first part of the work reported here focuses on the cellular effects of the metabolically stable dinuclear platinum compound, BBR3610-DACH. Comet assay showed this compound to form interstrand crosslinks, a highly toxic DNA lesion in HCT116 cells, at equimolar concentrations to its parental compound, BBR3610. Cell cycle studies showed that BBR3610-DACH causes G1/S and G2/M cell cycle arrest with S phase …

Determinants Of Abuse-Related Effects Of Monoamine Releasers In Rats, Clayton T. Bauer

Theses and Dissertations

Monoamine releasers constitute a class of compounds that promote release of dopamine, serotonin, and/or norepinephrine. These compounds have a range of different uses in the medical setting, including treatment of attention deficit hyperactivity disorder, narcolepsy, and obesity. A major limitation of many of these compounds (i.e. amphetamine, methamphetamine, phenmetrazine) is their propensity for abuse; however, not all monoamine releasers are abused (i.e. fenfluramine). The goal of this dissertation was to examine pharmacological determinants of abuse-related effects produced by monoamine releasers in two preclinical assays in rats: intracranial self-stimulation (ICSS) and drug discrimination. First, this work confirmed and expanded upon previous …

Effects Of Mu Opioid Receptor Agonists On Intracranial Self-Stimulation In The Absence And Presence Of “Pain” In Rats, Ahmad Altarifi

Theses and Dissertations

Pain is a significant health problem. Mu opioid receptor agonists are used clinically as analgesics, but their use is constrained by high abuse liability. Intracranial self-stimulation (ICSS) is a preclinical behavioral procedure that has been used to assess abuse potential of opioids, and drug-induced facilitation of ICSS is interpreted as an abuse-related effect. ICSS can also be used as a behavioral baseline to detect affective dimensions of pain. Specifically, pain-related depression of ICSS can model pain-related depression of behavior and mood, and drug-induced blockade of pain-related ICSS depression can serve as a measure of affective analgesia. This dissertation used mu …

Effect Of Cannabinoids On Pain-Stimulated And Pain-Depressed Behavior In Rats, Andrew Kwilasz

Theses and Dissertations

Cannabinoids produce antinociception in many preclinical models of acute and chronic pain. In contrast, cannabinoids produce inconsistent analgesia in humans, showing little or no efficacy in treating acute pain, with modest efficacy in treating chronic inflammatory pain. This discrepancy may reflect an overreliance on preclinical assays of pain-stimulated behaviors, defined as behaviors that increase in rate or intensity following delivery of a noxious stimulus. In these assays, antinociception is indicated by a reduction in pain-stimulated behaviors, and antinociception is produced either by a reduction in sensory sensitivity to the noxious stimulus (i.e. true analgesia) or by false positive motor impairment. …

Ethanol Regulation Of Glucocorticoid Responsive Genes, Blair Costin

Theses and Dissertations

Glucocorticoid hormones modulate acute and chronic behavioral and molecular responses to drugs of abuse including psychostimulants and opioids. Acute ethanol activates the hypothalamic pituitary adrenal (HPA) axis causing the release of adrenal glucocorticoid hormones, but following chronic ethanol the HPA axis is dysregulated in both humans and rodents. Thus, there is growing evidence that glucocorticoids might also modulate behavioral and molecular responses to ethanol. Previous microarray studies in the Miles’ laboratory have shown that the well-known glucocorticoid responsive gene, Serum and Glucocorticoid-regulated Kinase 1, Sgk1, is prominently up regulated by acute ethanol (2 g/kg) in the prefrontal cortex (PFC) of …

The Role Of Nicotinic Acetylcholine Receptors In Ethanol Responsive Behaviors And Drinking, Anton Dawson

Theses and Dissertations

The high co-morbidity between alcohol (ethanol) and nicotine abuse suggests that nicotinic acetylcholine receptors (nAChRs), which are thought to underlie nicotine dependence, may also be involved in alcohol dependence. A genomic region that encodes the Alpha5* nAChR subtype has recently been shown to be associated with alcohol dependence phenotypes in humans. Therefore, the aim of this study was to determine the role of Alpha5* nAChRs in ethanol-responsive behaviors upon acute administration in mice as well as in their drinking behavior. We conducted tests in mice lacking the Alpha5 coding gene (Chrna5) in ethanol-induced hypothermia, hypnosis, anxiolysis, and conditioned place preference. …

Ethanol Regulation Of Serum Glucocorticoid Kinase 1 Expression In Dba2/J Mouse Prefrontal Cortex, Blair N. Costin, Seth M. Dever, Michael F. Miles

Pharmacology and Toxicology Publications

Background

We previously identified a group of glucocorticoid-responsive genes, including Serum Glucocorticoid kinase 1 (Sgk1), regulated by acute ethanol in prefrontal cortex of DBA2/J mice. Acute ethanol activates the hypothalamic pituitary adrenal axis (HPA) causing release of glucocorticoids. Chronic ethanol dysregulates the HPA response in both humans and rodents, possibly contributing to important interactions between stress and alcoholism. Because Sgk1regulates ion channels and learning and memory, we hypothesized that Sgk1 contributes to HPA-dependent acute and adaptive neuronal responses to ethanol. These studies characterized acute and chronic ethanol regulation of Sgk1 mRNA and protein and their relationship with ethanol actions …

Cannabinoid Cb2 Receptors Regulate Central Sensitization And Pain Responses Associated With Osteoarthritis Of The Knee Joint, James J. Burston, David R. Sagar, Pin Shao, Mingfeng Bai, Emma King, Louis Brailsford, Jenna M. Turner, Gareth J. Hathway, Andrew J. Bennett, David A. Walsh, David A. Kendall, Aron H. Lichtman, Victoria Chapman

Pharmacology and Toxicology Publications

Osteoarthritis (OA) of the joint is a prevalent disease accompanied by chronic, debilitating pain. Recent clinical evidence has demonstrated that central sensitization contributes to OA pain. An improved understanding of how OA joint pathology impacts upon the central processing of pain is crucial for the identification of novel analgesic targets/new therapeutic strategies.

Inhibitory cannabinoid 2 (CB2) receptors attenuate peripheral immune cell function and modulate central neuro-immune responses in models of neurodegeneration. Systemic administration of the CB2 receptor agonist JWH133 attenuated OA-induced pain behaviour, and the changes in circulating pro- and anti-inflammatory cytokines exhibited in this model. Electrophysiological studies revealed that …

Fyn-Dependent Gene Networks In Acute Ethanol Sensitivity, Sean P. Farris, Michael F. Miles

Pharmacology and Toxicology Publications

Studies in humans and animal models document that acute behavioral responses to ethanol are predisposing factor for the risk of long-term drinking behavior. Prior microarray data from our laboratory document strain- and brain region-specific variation in gene expression profile responses to acute ethanol that may be underlying regulators of ethanol behavioral phenotypes. The non-receptor tyrosine kinase Fyn has previously been mechanistically implicated in the sedative-hypnotic response to acute ethanol. To further understand how Fyn may modulate ethanol behaviors, we used whole-genome expression profiling. We characterized basal and acute ethanol-evoked (3 g/kg) gene expression patterns in nucleus accumbens (NAC), prefrontal cortex …

Contribution Of Nadph Oxidase To Membrane Cd38 Internalization And Activation In Coronary Arterial Myocytes, Ming Xu, Xiao-Xue Li, Joseph K. Ritter, Justine M. Abais, Yang Zhang, Pin-Lan Li

Pharmacology and Toxicology Publications

The CD38-ADP-ribosylcyclase-mediated Ca2+ signaling pathway importantly contributes to the vasomotor response in different arteries. Although there is evidence indicating that the activation of CD38-ADP-ribosylcyclase is associated with CD38 internalization, the molecular mechanism mediating CD38 internalization and consequent activation in response to a variety of physiological and pathological stimuli remains poorly understood. Recent studies have shown that CD38 may sense redox signals and is thereby activated to produce cellular response and that the NADPH oxidase isoform, NOX1, is a major resource to produce superoxide (O2·−) in coronary arterial myocytes (CAMs) in response to muscarinic receptor agonist, which uses CD38-ADP-ribosylcyclase …

Early Adolescent Nicotine Exposure Has Long-Lasting Effects On Cocaine-Induced Behaviors In Mice, Mai Alajaji

Theses and Dissertations

Nicotine is one of the most commonly used drugs among adolescent populations. Given the fact that adolescence is a unique developmental stage, during which nicotine has long-term effects on future drug-taking behavior, it is essential to understand how early exposure to nicotine during adolescence may affect the abuse liability of other drugs. We hypothesize that repeated exposure to low doses of nicotine in adolescence induce age-specific enhancement of the rewarding effects of several drugs of abuse in the conditioned place preference (CPP) test. Furthermore, we predict that these changes in behavioral responses are mediated by nicotine-induced brain region-specific increases in …

Role Of Tyrosyl-Dna Phosphodiesterase (Tdp 1) On Repair Of 3′-Phosphoglycolate (3′- Pg) Terminated Dna Double-Strand Breaks (Dsbs) And In Response To Oxidative Stress, Tong Zhou

Theses and Dissertations

DNA DSBs are most toxic to cells because they can lead to genomic rearrangements and even cell death. Most DSBs induced by ionizing radiation or radiomimetic drugs such as calicheamicin and bleomycin, bear 3′-phosphate or 3′- PG moieties that must be removed to allow subsequent gap filling and ligation. DSBs can be repaired by two main pathways: the homologous recombination (HR) pathway and the non-homologous end-joining (NHEJ) pathway, NHEJ is the primary repair pathway in mammalian cells. While HR repairs single strand breaks (SSBs) or DSBs accurately by using an undamaged copy of the sequence mostly at late S phase …

Investigating A Model For Fetal Alcohol Damage In Caenorhabditis Elegans, Lindsay Kondo

Theses and Dissertations

Alcohol use and abuse has many harmful effects, especially to children exposed prenatally, including fetal alcohol spectrum disorders (FASDs). The disabilities due to fetal alcohol exposure continue throughout life and cause major financial burdens to society. The molecular mechanisms underlying FASDs are not well understood. We have taken a genetic approach to characterize ethanol’s effect on changing a discrete cell fate decision during embryogenesis in the nematode, Caenorhabditis elegans (C. elegans). Our preliminary data suggest that ethanol can affect the development of AWC neurons, a pair of olfactory neurons in C. elegans. We suggest that lipids can protect AWC neurons …

The Role Of Magl Inhibition In Nicotine Withdrawal And Reward, Pretal Muldoon

Theses and Dissertations

ROLE OF MAGL INHIBITION IN NICOTINE WITHDRAWAL AND REWARD. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. by Pretal Ishvarlal Patel Muldoon Director: M. Imad Damaj, PhD Professor, Department of Pharmacology and Toxicology Tobacco use is one of the leading causes of preventable deaths worldwide. Nicotine, the main psychoactive component of tobacco, sustains and initiates tobacco addiction. Cessation of nicotine induces a dependence withdrawal syndrome. Recent in vivo studies indicate that the endocannabinoid (EC) system modulates both nicotine reward and withdrawal. The purpose of this proposal is to …

Role Of Autophagy In The Response Of Hs578t Breast Tumor Cells To Radiation, Shweta Chakradeo

Theses and Dissertations

Breast cancer is the most commonly observed cancer type in women and is the second leading cause of cancer death in women. Radiation can be used to debulk tumors prior to surgery as well as to treat patients after surgery and/or chemotherapy. Previous studies from our laboratory have shown that the anti –malarial drug chloroquine sensitizes breast cancer cell lines to radiation by suppression of autophagy which is a conservative catabolic process that can be cytoprotective. The scientific literature has demonstrated that many tumor cell systems undergo cytoprotective autophagy and that pharmacological or genetic inhibition of autophagy leads to other …

Role Of Nicotinic Acetylcholine Receptors In Experimental Colitis, Shakir Alsharari

Theses and Dissertations

Substantial evidence in the literature shows that tobacco smoking has complex and divergent effects on inflammatory bowel diseases (IBD). It ameliorates ulcerative colitis (UC); whereas it aggravates the risk of Crohn’s disease (CD) and affects the disease course and severity. Studies have shown that nicotine has a positive influence on symptoms of UC. Also, it is demonstrated that nicotinic acetylcholine receptor, especially α7 subunit plays an essential component in the vagus nerve-based cholinergic anti-inflammatory effects. In the present study, we explored the effect of nicotine and α7 nicotinic agonists treatment in the DSS colitis mouse model. We also investigated the …

Development Of Natural Cyclic Peptide Inhibitors Of Xrcc4/Xlf Interaction For Radio-Sensitization Of Breast Tumor Cells, Mohaini Mohammed Al

Theses and Dissertations

Breast cancer is the second leading cause of cancer death in women according to the American Cancer Society. The standard treatment regimen for breast cancer involves ionizing radiation combined with surgery and chemotherapy. Ionizing radiation induces a complex signaling response in cells resulting in either growth arrest, senescence or cell death, and the cell killing after exposure to radiation results largely from DNA double-strand breaks (DSBs). There are two main mechanisms in mammalian cells responsible for repairing the DSBs; the primary mechanism is non-homologous end joining (NHEJ) and the secondary mechanism is homologous recombination (HRR). Previous studies showed that breast …

Cell Death And Growth Arrest Pathways Mediating The Actions Of Stilbene 5c In Hct-116 Colon Cancer Cells, Moureq Alotaibi

Theses and Dissertations

Abstract The stilbene derivative, cis-3, 4’, 5-trimethoxy-3’-aminostilbene (stilbene 5c), is a potentially potent antitumor agent that acts via binding to the colchicine-binding pocket in microtubules. Earlier studies have shown that stilbene 5c induces cell death in ovarian cancer cells and leukemic cells. The present study was designed to investigate the effectiveness of this microtubule poison against the HCT-116 human colon cancer cell line and its mechanisms of action. Time course studies demonstrated that stilbene 5c produces a biphasic decrease in cell viability. The capacity of the cells to proliferate was not restored upon removal of the drug after 6 days …

The Antinociceptive Effects Of Alpha 7 Nicotinic Acetylcholine Receptor Positive Allosteric Modulators In Different Animal Pain Models, Kelen Freitas

Theses and Dissertations

The α7 nicotinic acetylcholine receptor (nAChR) subtype is abundantly expressed in the central nervous system (CNS) and in the periphery. Positive allosteric modulators (PAMs) of the α7 increase the response to an agonist and are divided into two types depending on whether they also decrease desensitization of the receptor (type II) or not (type I). Therefore, this study aims to investigate whether the enhancement of endogenous α7 nAChR function will result in a beneficial effect in nociceptive, inflammatory and chronic neuropathic pain models. While NS1738 and PNU-120596 were not active to reduce acute thermal pain, measured by hot-plate and tail-flick …

Radiation Sensitization Of Breast Cancer Cells By Vitamin D Through The Promotion Of Autophagic Cell Death, Eden Wilson

Theses and Dissertations

Radiation therapy is a widely used tool in cancer therapy and is frequently offered as the first line of treatment for cancers of the breast. While radiotherapy is often initially effective in killing tumor cells or suppressing their growth, there are factors that confer tumor cell resistance to irradiation. Development of resistance may lead to disease recurrence despite the use of surgery, chemotherapy and radiation therapy. A primary goal of the studies in Dr. Gewirtz’s laboratory is to develop strategies to overcome resistance to radiation (and chemotherapy) in breast cancer, with the ultimate goal of preventing or attenuating disease recurrence. …

Hydrogen Sulfide As An Allosteric Modulator Of Atp Sensitive Potassium Channels In Colonic Inflammation., Aravind Gade

Theses and Dissertations

The ATP sensitive potassium channel (KATP) in mouse colonic smooth muscle cell is a complex containing a pore forming subunit (Kir6.1) and a sulfonyl urea receptor subunit (SUR2B). These channels are responsible for maintaining the cellular excitability of the smooth muscle cell which in turn regulates the motility patterns in the colon. We used whole-cell voltage-clamp techniques to study the alterations in these channels in smooth muscle cells in experimental model of colitis (colonic inflammation). Colitis was induced in BALB/C mice following an intracolonic administration of trinitrobenzene sulfonic acid (TNBS). KATP currents were measured at Vh -60 mV in high …

Myelin Gene Expression: Implications For Alcohol Abuse And Dependence, Sean Farris

Theses and Dissertations

Acute behavioral responses to ethanol have predictive value for determining an individual's risk of long-term drinking behavior. Although the neurobiology of alcohol abuse is complex, prior studies from our laboratory demonstrated differential myelin-associated gene expression (MAGE) in medial prefrontal cortex (PFC) as one potential mechanism influencing acute ethanol behaviors between C57BL/6J (B6) and DBA/2J (D2) mice. Our laboratory and others have also shown MAGE is reduced in PFC of alcoholics. Herein, I have extended these findings through expression profiling of PFC into chronic models of ethanol self-administration from non-human primates and mice. Together, these results suggest that regulation of MAGE …

Antinociceptive Effects Of Monoamine Reuptake Inhibitors In Assays Of Pain-Stimulated And Pain-Depressed Behaviors, Marisa Rosenberg

Theses and Dissertations

ANTINOCICEPTIVE EFFECTS OF MONOAMINE REUPTAKE INHIBITORS IN ASSAYS OF PAIN-STIMULATED AND PAIN-DEPRESSED BEHAVIOR By Marisa B. Rosenberg A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University. Virginia Commonwealth University, 2012 Advisor: Sidney Stevens Negus, Ph.D. Professor, Department of Pharmacology/Toxicology Noxious stimuli can produce pain-related stimulation of some behaviors (e.g. withdrawal responses) and depression of other behaviors (e.g. feeding, locomotion, responding maintained by many types of positive reinforcement). Monoamine reuptake inhibitors are used clinically to treat depression and to manage some types of pain. This study examined the antinociceptive properties …

Elevating Endogenous Cannabinoids Reduces Opioid Withdrawal In Mice, Divya Ramesh

Theses and Dissertations

Delta9-tetrahydrocannbinol (THC), the primary active constituent of Cannabis sativa, has long been known to reduce opioid withdrawal symptoms. Although THC produces most of its pharmacological actions through the activation of CB1 and CB2 cannabinoid receptors, the role these receptors play in reducing opioid withdrawal symptoms remains unknown. The endogenous cannabinoids, N-arachidonoylethanolamine (anandamide; AEA) and 2-arachidonylglycerol (2-AG), activate both cannabinoid receptors, but are rapidly metabolized by fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), respectively. The objective of this dissertation was to test whether increasing AEA or 2-AG, via inhibition of their respective hydrolytic enzymes, reduces morphine withdrawal symptoms in …

Dynamics Of Substrate Interactions In Trna (M1g37) Methyltransferase: Implications For Drug Discovery, Maria Kiouppis Palesis

Theses and Dissertations

The bacterial enzyme t-RNA (m1G37) methyltransferase (TrmD) is an ideal anti-microbial drug target since it is found in all eubacteria, serves an essential role during protein synthesis, and shares very little sequence or structural homology with its eukaryotic counterpart, Trm5. TrmD, a homodimeric protein, methylates the G37 nucleotide of tRNA using S-adenosyl-L-methionine (SAM) as the methyl donor and thus enables proper codon-anticodon alignment during translation. The two deeply buried binding sites for SAM seen in X-ray crystallography suggest that significant conformational changes must occur for substrate binding and catalytic turnover. Results from molecular dynamics simulations implicate a flexible loop region …

Low Dose Nicotine And Antagonism Of Β2 Subunit Containing Nicotinic Acetylcholine Receptors Have Similar Effects On Affective Behavior In Mice, Shawn M. Anderson, Darlene H. Brunzell

Pharmacology and Toxicology Publications

Nicotine leads to both activation and desensitization (inactivation) of nicotinic acetylcholine receptors (nAChRs). This study tested the hypothesis that nicotine and a selective antagonist of β2*nAChRs would have similar effects on affective behavior. Adult C57BL/6J male mice were tested in a conditioned emotional response (CER) assay which evaluates the ability of an aversive stimulus to inhibit goal-directed behavior. Mice lever-pressed for a saccharin reinforcer according to a variable schedule of reinforcement during sessions in which two presentations of a compound light/tone conditioned stimulus (CS) co-terminated with a 0.1 or 0.3 mA, 0.5 s footshock unconditioned stimulus (US). During testing in …

Mice Deficient In Gem Gtpase Show Abnormal Glucose Homeostasis Due To Defects In Beta-Cell Calcium Handling, Jenny E. Gunton, Mary Sisavanh, Rebecca A. Stokes, Jon Satin, Leslie S. Satin, Min Zhang, Sue M. Liu, Weikang Cai, Kim Cheng, Gregory J. Cooney, D. Ross Laybutt, Trina So, Juan-Carlos Molero, Shane T. Grey, Douglas A. Andres, Michael S. Rolph, Charles R. Mackay

Pharmacology and Toxicology Publications

Aims and Hypothesis

Glucose-stimulated insulin secretion from beta-cells is a tightly regulated process that requires calcium flux to trigger exocytosis of insulin-containing vesicles. Regulation of calcium handling in beta-cells remains incompletely understood. Gem, a member of the RGK (Rad/Gem/Kir) family regulates calcium channel handling in other cell types, and Gem over-expression inhibits insulin release in insulin-secreting Min6 cells. The aim of this study was to explore the role of Gem in insulin secretion. We hypothesised that Gem may regulate insulin secretion and thus affect glucose tolerance in vivo.

Methods

Gem-deficient mice were generated and their metabolic phenotype characterised by …

Lipid Environment Modulates The Development Of Acute Tolerance To Ethanol In Caenorhabditis Elegans, Jill C. Bettinger, Kapo Leung, Mia H. Bolling, Andrew D. Goldsmith, Andrew G. Davies

Pharmacology and Toxicology Publications

The development of tolerance to a drug at the level of the neuron reflects a homeostatic mechanism by which neurons respond to perturbations of their function by external stimuli. Acute functional tolerance (AFT) to ethanol is a fast compensatory response that develops within a single drug session and normalizes neuronal function despite the continued presence of the drug. We performed a genetic screen to identify genes required for the development of acute functional tolerance to ethanol in the nematode C. elegans. We identified mutations affecting multiple genes in a genetic pathway known to regulate levels of triacylglycerols (TAGs) via …