Jonathan Covault - US grants

A continual interplay between neurons and their targets is fundamental to the development, maintenance and modification of synapses. Our long term goals are to identify molecules mediating these interactions and gain an understanding of their regulation. The neuromuscular systems provides a well characterized, relatively simple system in which to study these instructions. Recent studies of the neural cell adhesion molecule (N-CAM) suggest it plays an important role in nerve-muscle adhesion during synapse formation. Levels of N-CAM are regulated in turn by neural activity. By studying synapse formation in nerve-muscle co-cultures using variant cell lines deficient in N-CAM we will provide a more critical examination of the importance of N-CAM in neuromuscular synaptogenesis. Using specific antibodies and cDNA probes to N-CAM we will study the neural regulation of muscle N-CAM expression, and by molecular genetic analysis of selected N-CAM deficient variants we will identify genes required for N-CAM RNA accumulation. Finally, we will search for muscle specific differences in N-CAM structure which could play a role in selective synapse formation.

neurogenetics; smooth pursuit eye movement; erythema; schizophrenia; genetic markers; auditory stimulus; evoked potentials; linkage mapping; sensory mechanism; family genetics; behavioral genetics; neurophysiology; sensation; niacin; patient oriented research; human subject; clinical research; human genetic material tag;

genetic susceptibility; cannabinoid receptor; substance abuse related disorder; genetic markers; behavioral genetics; alleles; Cannabis; alcoholism /alcohol abuse; drug addiction; genetic mapping; clinical research; human genetic material tag; human subject;

[unreadable] DESCRIPTION (provided by applicant): Studies of the genetic basis of alcohol's effects and their modification by pharmacological agents represent a promising approach to the development of medications to treat problem drinking and alcohol dependence. This proposal employs a human laboratory paradigm to study the moderating effect of genetic variation of GABRA2, which encodes the GABAA-receptor alpha-2 subunit and GABAergic neuroactive steroids on subjective and physiological effects of alcohol when consumed by light drinkers compared with heavy drinkers. This study will explore the hypothesis that effects of alcohol are in part mediated by increased production of neuroactive steroids, which interact with GABAA-receptors. We propose to study non-dependent drinkers using a 4-session within- subjects design in which alcohol / placebo is paired with dutasteride / placebo pretreatment. Dutasteride is a 5-alpha steroid reductase (5AR) inhibitor that limits the production of dihydrotestosterone and the 5alpha-reduced neuroactive steroids allopregnanolone, pregnanolone and 3alpha, 5alpha-THDOC. This work continues our pilot studies in this area in which we demonstrated that both an alcohol-dependence associated GABRA2 allele and inhibition of 5AR reduce the subjective response to alcohol. We will extend work in this area by 1) examining a larger group of subjects that includes both light and heavy drinkers balanced on GABRA2 genotype, 2) include objective measures of alcohol's effects, 3) measure plasma concentrations of neuroactive steroids and their adrenal steroid hormone precursors at several time points following alcohol, 4) examine effects of a more potent and specific inhibitor of 5alpha-reductase (to validate and clarify the relationship of neuroactive steroids to alcohol effects), and 5) examine the effects of polymorphisms in steroid 5alpha-reductase and mu-opioid receptor genes on alcohol-induced neuroactive steroid elevations and behavioral responses. To conduct this work, we have developed collaborations among several investigators with expertise in human alcohol challenge studies and the physiological effects of alcohol, genetics, and steroid hormone analysis, and will make use of an NIH-funded GCRC to augment resources. This study provides a foundation for translating pre-clinical findings on neuroactive steroids to the development of medications to treat alcohol use disorders. Public information description: Alcohol abuse and dependence remain important public health problems. Inherited (e.g. genetic) risk factors are thought to be important in the development of alcohol use problems. This proposal employs a human laboratory paradigm to study the moderating effect of genetic variation in several candidate genes and the role of alcohol induced neuroactive steroids on subjective and physiological effects of alcohol when consumed by light drinkers compared with heavy drinkers. [unreadable] [unreadable]

Abnormal coordination; Acute; Alcohol abuse; Alcohol dependence; Alcohols; Alleles; Allelomorphs; Ataxia; Ataxy; BrAC; CRISP; Case-Base Studies; Case-Comparison Studies; Case-Compeer Studies; Case-Control Studies; Case-Referent Studies; Case-Referrent Studies; Chemical Class, Alcohol; Co-ordination disorder; Cognitive; Computer Retrieval of Information on Scientific Projects Database; Coordination Disorder; Coordination Impairment; Data; Dependence; Development; Dyscoordination; Dyssynergia; Ethanol dependence; Extremities; Family; Funding; Genes; Genetic; Genetic Determinism; Genotype; Grant; Hereditary; Human; Human, General; Incoordination; Individual; Inherited; Institution; Investigators; Lack of Coordination; Limb structure; Limbs; Man (Taxonomy); Man, Modern; Measures; Memory, Immediate; Memory, Short-Term; Memory, Shortterm; Motor; NIH; National Institutes of Health; National Institutes of Health (U.S.); Non-Trunk; Performance; Public Health; Receptor Protein; Research; Research Personnel; Research Resources; Researchers; Resources; Rewards; Risk; Sedation procedure; Short-Term Memory; Source; Thinking; Thinking, function; United States National Institutes of Health; Variant; Variation; alcohol addiction; alcohol breath analysis; alcohol dependency; alcohol effect; alcohol problem; alcohol response; alcohol use disorder; alcohol-dependent; assay of breath alcohol; assay of breath ethanol; base; breath alcohol concentration; breath alcohol measurement; breath alcohol test; breath ethanol concentration; breath ethanol measurement; breath ethanol test; ethanol abuse; ethanol addiction; ethanol breath analysis; ethanol dependency; ethanol effect; ethanol response; ethanol use disorder; ethanol-dependent; genetic determinant; genetic risk factor; hazardous alcohol use; inherited factor; problem drinking; public health medicine (field); receptor; response; response to alcohol; response to ethanol; sedation; social; working memory

[unreadable] DESCRIPTION (provided by applicant): Stress- and negative-affect related drinking and drug use (SNAD) is an especially important maladaptive substance use (SU) pattern that results in negative outcomes (e.g. increased academic and interpersonal problems, driving under the influence of alcohol, delinquent activity, and getting involved in regrettable sexual situations) in adolescents and college students. Given the public health risk associated with these outcomes, this project seeks to engage an interdisciplinary team to identify the factors that promote SNAD in college students. Emergent research suggests that two classes of factors - social learning factors and genetic variation in stress and affective reactivity - represent important risks for engagement in SNAD. The goal of the proposed research is to develop and refine interdisciplinary methodologies to examine the interaction of variation in select candidate genes with mood, psychological expectancies, and life stress to enhance our understanding of college students' SNAD. We will simultaneously examine the roles of social learning and genetic vulnerabilities for engaging in drinking or drug use in response to stress- and affect-related triggers in a sample of 700 college students. In view of the relative paucity of research of this kind in minority populations, we will conduct this study at a college campus with a predominantly African American (AA) student body. This project will unite two previously isolated lines of research on SU behavior, social learning and genetics, in order to investigate SNAD at two levels of analysis: the between-person (MACRO) level, i.e., how social learning factors and genes interact with major life stressors to influence average SU, and the within-person (MICRO) level, i.e., how social learning factors and genes interact with daily stressors to influence SU on a day-to-day basis. This study will involve collaborative efforts by an inter-disciplinary team of investigators who conduct research on the psychosocial, genetic, and endocrine bases of behavior related to substance use and dependence. This project is an outgrowth and extension of recently initiated collaborations of the two PIs over the past 2 years and applies the use of robust month-long daily data capture methodologies and DNA collection/genotyping. We will augment these measures with a salivary cortisol measure of hypothalamic- pituitary-adrenal (HPA) axis activity as a biological measure of inter-individual responses to stress. Understanding the contributions of social learning and genetic risk factors to SNAD at both macro and micro levels is important, as it will inform prevention efforts by potentially allowing early identification of individuals at greatest risk for problem SU, including alcohol and drug use disorders. Results may also make it possible to match specific treatments to individuals' vulnerabilities. Alcohol and drug use among college students is an important public health issue. Emerging research suggests that social learning factors interacting with individual genetic variation and with life stress influence the risk of maladaptive substance use behavior. This proposal seeks to develop robust and novel methodologies to use internet-based technologies to capture daily data about college student life events and behavior related to substance use, and to integrate this information with emerging knowledge about natural variation in genes related to stress reactivity. [unreadable] [unreadable] [unreadable]

17beta-N-(2,5-bis(trifluoromethyl))phenyl-carbamoyl-4-aza-5alpha-androst-1-en-3-one; 3 alpha-Hydroxy-5 alpha-pregnan-20-one; 4-Azaandrost-1-ene-17-carboxamide, N-(1,1-dimethylethyl)-3-oxo-, (5alpha,17beta)-; ADRGND; Acute; Adrenal Glands; Adrenals; Agonist; Alcohol dependence; Alcoholic; Alcoholic beverage heavy drinker; Alcohols; Allopregnanolone; Animals; Ataxia; Ataxy; Beverages; Blood Plasma; Boozer; CRISP; Chemical Class, Alcohol; Computer Retrieval of Information on Scientific Projects Database; Coordination Impairment; Dehydrogenases; Dependent drinker; Dutasteride; Dyssynergia; Enzymes; Ethanol dependence; Family; Feedback; Finasteride; Funding; Gene variant; Genes; Genetic; Genetic Diversity; Genetic Polymorphism; Genetic Variation; Grant; HPA; HPR1; HPSE; HPSE gene; HPSE1; HSE1; Heavy Drinker; Human; Human, General; Institution; Investigators; Isoenzymes; Isozymes; Laboratory Study; Light; Man (Taxonomy); Man, Modern; NIH; National Institutes of Health; National Institutes of Health (U.S.); Opioid Receptor; Oxidoreductase; PBO; Photoradiation; Placebo Control; Placebos; Plasma; Polymorphism (Genetics); Polymorphism, Genetic; Pregnanolone, (3alpha,5alpha)-isomer; Production; Receptor Gene; Receptor Protein; Receptors, Opiate; Reductases; Regulation; Research; Research Personnel; Research Resources; Researchers; Resources; Reticuloendothelial System, Serum, Plasma; Risk; Role; Serum, Plasma; Sham Treatment; Source; Steroid Compound; Steroids; Testing; Therapeutic Steroid Hormone; Time; United States National Institutes of Health; Variant; Variation; Variation (Genetics); alcohol addiction; alcohol dependency; alcohol effect; alcohol-dependent; allelic variant; base; case control; design; designing; ethanol addiction; ethanol dependency; ethanol effect; ethanol-dependent; genetic variant; hypothalamic-pituitary-adrenal (HPA) axis; hypothalamic-pituitary-adrenal axis; hypothalmus-pituitary-adrenal axis; inhibitor; inhibitor/antagonist; polymorphism; problem drinker; receptor; response; sham therapy; social role; steroid hormone; suprarenal gland

FDA approved pharmacotherapy options for alcohol use disorders remain limited, with only three currently approved compounds (disulfiram, naltrexone and acamprosate). Recent studies highlight the potential for medications used for the treatment of other indications to be examined for the treatment of alcohol use disorders. Study of additional agents, particularly those that act through novel mechanisms, is needed to expand the range of pharmacotherapy options for alcohol use problems. Extensive preclinical studies indicate that neuroactive steroids medicate important effects of alcohol and support the examination of neuroactive steroid modulators as treatment options for alcohol use problems. Dutasteride, a widely prescribed medication for benign prostatic hypertrophy, bloci

DESCRIPTION (provided by applicant): Pharmacogenetics has the potential to inform individualized medication treatment decisions by characterizing the role of natural genetic variation in moderating treatment response or adverse effects. Recent studies have shown that the medication topiramate, which is used to treat epilepsy, is also effective in reducing heavy drinking in patients with alcohol use disorder. A common variation in the gene GRIK1 that encodes one of the key proteins targeted by topiramate, the Gluk1 glutamate receptor subunit, has been associated with alcohol dependence and with treatment response to topiramate for reducing alcohol use in treatment seeking heavy drinkers. This project will use neural cells generated in the laboratory from reprogrammed pluripotent stem cells derived from adult skin cells donated by characterized alcoholic and non-alcoholic subjects to examine the effects of GRIK1 genetic variation and of alcohol combined with topiramate on the expression and function of the GluK1 glutamate receptor in human neural cells in vitro. This work will employ quantitative gene expression assays of GRIK1 RNA isoforms, antisense RNA, RNA editing and next generation sequencing as well as electrophysiology records of pharmacologically isolated GluK1 containing kainate receptors. We anticipate that results from this work will provide a better understanding of the biological basis for differential responses of alcoholic subjects to topiramate treatment and thereby increase the potential to provide individualized treatment planning for persons with alcohol use problems.

Abstract Pharmacotherapy options for alcohol use disorders remain limited, with only three FDA approved compounds (disulfiram, naltrexone and acamprosate). Recent studies highlight the potential for medications used for the treatment of other indications to be useful in helping patients reduce drinking. Study of additional agents, particularly those that act through novel mechanisms, is needed to expand the range of pharmacotherapy options for alcohol use problems. Additionally, identification of individual subject level predictors of efficacy are needed to better personalize pharmacotherapy treatment recommendations. Extensive preclinical studies indicate that neuroactive steroids mediate important effects of alcohol and support the examination of neuroactive steroid modulators as treatment options for alcohol use disorders (AUD). Dutasteride, a widely prescribed medication for benign prostatic hypertrophy and androgenic hair loss, blocks a key step in the production of neuroactive steroids and represents a promising candidate for treatment of AUD. Interim analysis from the first 12-week RCT of dutasteride for AUD in a sample of male heavy drinkers indicates that dutasteride is well tolerated in alcoholics and has efficacy in helping subjects reduce drinking. Results suggest that dutasteride may be particularly helpful for patients with baseline negative mood or are carriers of a stress-reactive allele of a chaperone protein, FKBP5, involved in regulation of glucocorticoid, androgen and progesterone receptor function. This 24-week treatment study will use an innovative step therapy randomized placebo controlled design to examine the safety and efficacy of dutasteride to reduce drinking among a sample of 190 treatment seeking men and women with hazardous levels of alcohol use. At 12-weeks placebo non-responders will transition to dutasteride and dutasteride non-responders will transition to naltrexone, an FDA approved medication with demonstrated efficacy for reducing heavy drinking. Baseline measures of anxiety and perceived life stress will be examined separately and in conjunction with stress resilient vs. reactive genotypes of FKBP5 as predictors of dutasteride treatment efficacy.