Broad disruption of brain white matter microstructure and relationship with neuropsychological performance in male patients with severe alcohol dependence.

Aims In the last years, refined magnetic resonance diffusion tensor imaging (DTI) methods have become available to study microstructural alterations in the human brain. We investigated to what extent white matter tissue abnormalities are present in male patients after chronic, excessive alcohol consumption and if these alterations are correlated with measures of alcohol consumption and neuropsychological performance. Methods Twenty-four detoxified adult male patients with severe alcohol dependence and 23 healthy male control subjects were included in the study. Neuropsychological tests were assessed for executive function, attention, memory and visuospatial function. DTI was acquired and pr…

Serotonergic polymorphisms in patients suffering from alcoholism, anxiety disorders and narcolepsy.

Abstract 1. Alterations in the serotonergic neurotransmission have been frequently described for patients suffering from alcoholism, anxiety disorders and narcolepsy. 2. The authors tested for association of the 5-HT2A receptor polymorphism (T102C) and the intron 7 tryptophan hydroxylase (TPH) polymorphism (A218C) among 176 alcohol dependent patients, 35 patients with panic disorder, 50 patients with generalized anxiety disorder, 55 patients with narcolepsy and 87 healthy controls. 3. Allele and genotype frequencies of the 5-HT2A receptor polymorphism (T102C), the intron 7 TPH polymorphism (A218C) were almost similar between the patients suffering from alcohol dependence, panic disorder, ge…

Sex differences in allelic frequencies of the 5-HT2C Cys23Ser polymorphism in psychiatric patients and healthy volunteers: findings from an association study

Polymorphisms in the serotonergic system are believed to play a role in the etiology and treatment of different psychiatric illnesses. The 5-HT2C receptor gene is X-linked, with a frequent mutation at nucleotide 68 leading to a Ser-->Cys transition at amino acid 23. Recent studies have demonstrated an impaired function of 5-HT2C receptors and an increased production of the major noradrenergic metabolite 3-methoxy-4-hydroxyphenylethyleneglycol in the cerebrospinal fluid among the subjects carrying the Ser23 allele (Lappalainen et al., 1999). Biol. Psychiatry 46:821). We genotyped patients with alcohol dependence, panic disorder without agoraphobia, generalized anxiety disorder, narcolepsy an…

Quantitation of GABA transporter 3 (GAT3) mRNA in rat brain by competitive RT-PCR.

Gamma-amino butyric acid is the major inhibitory neurotransmitter in the brain. GABA transporters (GATs) remove GABA from the synaptic cleft. Till now, five distinct GABA transporters have been cloned and termed consecutively GAT1 to GAT4 and vGAT. To study the mechanisms by which tolerance and dependence associated with drugs enhancing GABAergic transmission is brought upon we analysed the mRNA expression levels of GATs in various brain regions under different conditions. In this paper, we describe our protocol for measurement of GAT3 mRNA expression, and its validation through control experiments for the various steps. We performed competitive reverse transcription and polymerase chain re…

Pro und Kontra: Monotherapie - Goldstandard der Psychopharmakabehandlung?

Confirmation of association of the GABRA2 gene with alcohol dependence by subtype-specific analysis

Objectives: Three recent studies revealed a haplotypic association of alcohol dependence with the gene encoding the {alpha}2 subunit of the {gamma}-aminobutyric acid type A (GABAA) receptor (GABRA2). The present study examined whether variation of the GABRA2 gene confers susceptibility to different subtypes of alcohol dependence in the German population. Methods: A total of 257 German alcohol-dependent patients and 88 healthy population controls were genotyped for six single-nucleotide polymorphisms covering the middle part and the 3′ end of GABRA2. Allelic, genotypic and haplotypic comparisons were done for subgroups of alcohol-dependent patients with a presumed high genetic load. Results:…

No association of alcohol dependence with HOMER 1 and 2 genetic variants.

Several lines of evidence indicate that alterations of the central cortico-accumbens glutamate pathway are involved in the development and maintenance of alcohol- and substance-use disorders. The HOMER protein family is encoded by 3 genes HOMER (1–3) which are components of the excitatory postsynaptic density complex and function to modulate synaptic activity by the regulation of glutamate signaling. HOMER 1 and 2 have been reported to contribute to chronic alcohol-induced long-term neurochemical changes in the endogenous reward system. Data from animal models suggest a potential role of the Homer protein family in the development of alcohol and substance use. The aim of this study is to as…

Alcohol Consumption in HealthyOPRM1G Allele Carriers and Its Association with Impulsive Behavior

AIMS: A link between alcohol use disorders (AUD) and impulsivity is well established. As there is evidence for the heritability of AUD, the investigation of the underlying genetic disposition for both conditions is an important issue. An association between AUD and a coding single nucleotide polymorphism (SNP) (rs1799971 encoding an Asn40Asp amino acid substitution, A118G) within the µ-opioid receptor 1 gene (OPRM1) has been reported. Therefore we tested the association between the OPRM1 A118G polymorphism and drinking as well as impulsive behavior in social drinkers. METHODS: A total of 214 healthy male social drinkers were recruited. Each participant was genotyped for the OPRM1 A118G vari…

Association of nicotinic acetylcholine receptor subunit alpha 4 polymorphisms with nicotine dependence in 5500 Germans.

Polymorphisms in the CHRNA4 gene coding the nicotinic acetylcholine receptor subunit alpha 4 have recently been suggested to play a role in the determination of smoking-related phenotypes. To examine this hypothesis, we conducted a genetic association study in three large samples from the German general population (N(1)=1412; N(2)=1855; N(3)=2294). Five single-nucleotide polymorphisms in CHRNA4 were genotyped in 5561 participants, including 2707 heavily smoking cases (regularly smoking at least 20 cigarettes per day) and 2399 never-smoking controls (or=100 cigarettes over lifetime). We examined associations of the polymorphisms with smoking case-control status and with the extent of nicotin…

Disturbed structural connectivity is related to inattention and impulsivity in adult attention deficit hyperactivity disorder

Inattention and impulsivity are the most prominent clinical features of attention deficit hyperactivity disorder (ADHD) in adulthood. Structural and functional neuroimaging studies of subjects with ADHD have demonstrated abnormalities in several brain areas, including fronto-striatal and fronto-cerebellar networks. Mostly, these studies were based on volumetric measurements and have been conducted in children. We investigated white matter (WM) integrity and correlation with measures of attention and impulsivity in adult patients with ADHD adopting diffusion tensor imaging (DTI). N = 37 (21 males) never-medicated adult patients with ADHD combined subtype and N = 34 (16 males) healthy control…

Association of ADH4 genetic variants with alcohol dependence risk and related phenotypes: results from a larger multicenter association study

Genetic variants of the alcohol-metabolizing enzyme ADH4, located on chromosome 4q22-4q23, have been related to alcohol dependence (AD) risk in previous research. The aim of this association study in a large multicenter sample of alcohol-dependent individuals and controls is to confirm ADH4 single nucleotide polymorphism (SNP) and haplotype association with AD and relevant related phenotypes. One thousand, six hundred and twenty-two (1622) inpatient subjects and 1469 control subjects with DSM-IV. AD from four addiction treatment centres were included. Characteristics of AD and related phenotypes including alcohol withdrawal, Cloninger's type I and II and first ages of drinking, regular drin…

Acute effect of intravenously applied alcohol in the human striatal and extrastriatal D2 /D3 dopamine system

Investigations on the acute effects of alcohol in the human mesolimbic dopamine D2 /D3 receptor system have yielded conflicting results. With respect to the effects of alcohol on extrastriatal D2 /D3 dopamine receptors no investigations have been reported yet. Therefore we applied PET imaging using the postsynaptic dopamine D2 /D3 receptor ligand [18 F]fallypride addressing the question, whether intravenously applied alcohol stimulates the extrastriatal and striatal dopamine system. We measured subjective effects of alcohol and made correlation analyses with the striatal and extrastriatal D2 /D3 binding potential. Twenty-four healthy male μ-opioid receptor (OPRM1)118G allele carriers underw…

Association of functional DBH genetic variants with alcohol dependence risk and related depression and suicide attempt phenotypes: Results from a large multicenter association study

Abstract Objective Dopamine-beta-hydroxylase (DBH) metabolizes the conversion of dopamine to noradrenaline. DBH, located on chromosome 9q34.2 has variants with potential functional consequences which may be related to alterations of neurotransmitter function and several psychiatric phenotypes, including alcohol dependence (AD), depression (MD) and suicidal behavior (SA). The aim of this association study in a large multicenter sample of alcohol-dependent individuals and controls is to investigate the role of DBH SNPs and haplotypes in AD risk and associated phenotypes (AD with MD or SA). Method 1606 inpatient subjects with DSM-IV AD from four addiction treatment centers and 1866 control sub…

Molecular cloning of rat G-protein-coupled receptor kinase 6 (GRK6) from brain tissue, and its mRNA expression in different brain regions and peripheral tissues

The rat G-protein-coupled receptor kinase 6 (GRK6) cDNA was cloned from rat brain tissue by a combination of reverse-transcription polymerase chain reactions (RT-PCR), based on homology to the cloned human GRK6, and rapid amplification of cDNA ends (RACE-PCR). We obtained a clone of 2817 bp with an open reading frame of 1731 bp encoding for a protein of 576 amino acids that is 96.7% identical and 97.9% similar to its human counterpart. mRNA was detectable in all brain areas examined. In addition, GRK6 was expressed in skeletal muscle, small intestine, aorta, liver, heart, lung, thymus, stomach, uterus and kidney.

Genome-wide Association Study of Alcohol Dependence

Context Alcohol dependence is a serious and common public health problem. It is well established that genetic factors play a major role in the development of this disorder. Identification of genes that contribute to alcohol dependence will improve our understanding of the mechanisms that underlie this disorder. Objective To identify susceptibility genes for alcohol dependence through a genome-wide association study (GWAS) and a follow-up study in a population of German male inpatients with an early age at onset. Design The GWAS tested 524 396 single-nucleotide polymorphisms (SNPs). All SNPs with P −4 were subjected to the follow-up study. In addition, nominally significant SNPs from genes t…

Mpdz is a quantitative trait gene for drug withdrawal seizures

Physiological dependence and associated withdrawal episodes can constitute a powerful motivational force that perpetuates drug use and abuse. Using robust behavioral models of drug physiological dependence in mice, positional cloning, and sequence and expression analyses, we identified an addiction-relevant quantitative trait gene, Mpdz. Our findings provide a framework to define the protein interactions and neural circuit by which this gene's product (multiple PDZ domain protein) affects drug dependence, withdrawal and relapse.

Disturbed brain activation during a working memory task in drug-naive adult patients with ADHD.

Neuroimaging studies in attention-deficit/hyperactivity disorder (ADHD) have shown abnormalities in several brain areas including the frontostriatal circuitry and were mostly conducted in children and adolescents. We investigated 30 never-medicated adult ADHD patients (16 males) and 30 matched healthy control individuals. Functional magnetic resonance imaging was acquired during a working memory paradigm (n-back). Group activation maps and group differences of activation were calculated using voxel-based analyses. The generic activation pattern was more extended in the control group. In ADHD patients, significantly decreased activation was found in the right inferior parietal cortex. Distur…

Possible association between OPRM1 genetic variance at the 118 locus and alcohol dependence in a large treatment sample: relationship to alcohol dependence symptoms.

Background Several lines of evidence from previous research indicate that opioid receptors play an important role in ethanol reinforcement and alcohol dependence (AD) risk. Conflicting results were reported on the role of the mu-opioid receptor (OPRM1) polymorphism A118G (Asn40Asp, rs1799971) in the development of alcoholism. Methods We investigated a total number of 1,845 alcohol-dependent subjects recruited from inpatient facilities in Germany and 1,863 controls for the mu-opioid receptor (OPRM1) polymorphism using chi-square statistics. Results An association between the OPRM variant and AD was detected (p = 0.022), in recessive (AA vs. GA/GG) and co-dominant (AA vs. GA) models of inheri…

The HTR1B 861GC receptor polymorphism among patients suffering from alcoholism, major depression, anxiety disorders and narcolepsy.

Abstract The HTR1B receptor gene has been linked to antisocial alcoholism in a Finnish population and an American Indian tribe [Lappalainen et al., Arch. Gen. Psychiatry, 55 (1998) 989]. Using a candidate gene approach, we genotyped 209 patients with alcoholism, 108 patients with major depression, 32 patients with panic disorder, 50 patients with generalized anxiety disorder, 58 patients with narcolepsy and 74 healthy volunteers for the HTR1B 861G>C polymorphism. There was a higher frequency of the HTR1B 861G alleles among the alcohol-dependent patients as compared to the control subjects (χ 2 =4.02, d.f.=2, P =0.04). However, the association resulted from higher frequencies of the opposite…

Severity of dependence modulates smokers' neuronal cue reactivity and cigarette craving elicited by tobacco advertisement

Smoking-related cues elicit craving and mesocorticolimbic brain activation in smokers. Severity of nicotine dependence seems to moderate cue reactivity, but the direction and mechanisms of its influence remains unclear. Although tobacco control policies demand a ban on tobacco advertising, cue reactivity studies in smokers so far have not employed tobacco advertisement as experimental stimuli. We investigated whether tobacco advertisement elicits cue reactivity at a behavioral (subjective craving) and a neural level (using functional magnetic resonance imaging) in 22 smokers and 21 never-smokers. Moreover, we studied the influence of severity of dependence on cue reactivity. In smokers, tob…

Dopamine D2/D3 receptor availability and venturesomeness.

The construct of impulsivity is considered as a major trait of personality. There is growing evidence that the mesolimbic dopamine system plays an important role in the modulation of impulsivity and venturesomeness, the two key components within the impulsivity-construct. The aim of the present study was to explore an association between trait impulsivity measured with self-assessment and the dopaminergic neurotransmission as measured by positron emission tomography (PET) in a cohort of healthy male subjects. In vivo D2/D3 receptor availability was determined with [(18)F]fallypride PET in 18 non-smoking healthy subjects. The character trait impulsivity was measured using the Impulsiveness-V…

Impulsiveness and venturesomeness in German smokers.

Introduction Cigarette smoking is a behavior, which is influenced by genetic, demographic, and psychological factors. A large body of research has examined the association of cigarette smoking variables with individual differences in personality traits. The aim of the current study was to replicate the findings of higher self-reported impulsivity in smokers compared with never-smokers in a German sample using Eysenck´s construct of impulsivity. Furthermore, it was intended to further the knowledge about associations between different self-reported impulsivity components and different smoking variables. Methods We used the Impulsiveness-Venturesomeness-Empathy questionnaire (I7) to measure s…

Risk gene variants for nicotine dependence in the CHRNA5-CHRNA3-CHRNB4 cluster are associated with cognitive performance

Recent studies strongly support an association of the nicotinic acetylcholine receptor gene cluster CHRNA5-CHRNA3-CHRNB4 with nicotine dependence (ND). However, the precise genotype-phenotype relationship is still unknown. Clinical and epidemiological data on smoking behavior raise the possibility that the relevant gene variants may indirectly contribute to the development of ND by affecting cognitive performance in some smokers who consume nicotine for reasons of "cognition enhancement." Here, we tested seven single nucleotide polymorphisms (SNPs) rs684513, rs637137, rs16969968, rs578776, rs1051730, rs3743078, rs3813567 from the CHRNA5-CHRNA3-CHRNB4 gene cluster for association with ND, me…

Human dopamine receptor D2/D3 availability predicts amygdala reactivity to unpleasant stimuli

r r Abstract: Dopamine (DA) modulates the response of the amygdala. However, the relation between dopa- minergic neurotransmission in striatal and extrastriatal brain regions and amygdala reactivity to affective stimuli has not yet been established. To address this issue, we measured DA D2/D3 receptor (DRD2/3) availability in twenty-eight healthy men (nicotine-dependent smokers and never-smokers) using positron emission tomography with ( 18 F)fallypride. In the same group of participants, amygdala response to unpleasant visual stimuli was determined using blood oxygen level-dependent (BOLD) functional mag- netic resonance imaging. The effects of DRD2/3 availability in emotion-related brain …

Biomarkers to disclose recent intake of alcohol: potential of 5-hydroxytryptophol glucuronide testing using new direct UPLC-tandem MS and ELISA methods

Aims: This study compared two new methods for direct determination of 5-hydroxytryptophol glucuronide (GTOL) in urine, a biomarker for detection of recent alcohol consumption. Methods: Urine samples were collected from ten alcoholic patients during recovery from intoxication. A direct injection ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for measurement of the urinary GTOL to 5-hydroxyindoleacetic acid (5-HIAA) ratio, and an ELISA assay for direct measurement of GTOL, were used. Comparison was made with the urinary ethanol and ethyl glucuronide (EtG) concentrations. Results: The breath ethanol concentration on admission ranged between 1.0-3.1 g/l. Th…

Rapid cloning of cDNA ends polymerase chain reaction of G-protein-coupled receptor kinase 6: an improved method to determine 5′- and 3′-cDNA ends

Abstract Rapid cloning of 5′- and 3′-cDNA ends polymerase chain reaction (5′-/3′-RACE-PCR) is useful to determine unknown 5′- and 3′-cDNA termini. Even if the method can yield complete cDNA sequences within a couple of days, the RACE procedure bears some characteristic traps and often results in amplification of unspecific PCR-products. Here we used improved 5′- and 3′-RACE-PCR protocols to obtain the complete cDNA sequence of the G-protein-coupled receptor kinase 6 (GRK6) from a rat brain cDNA library. The use of an anchored oligo-(dT) 16 -V-primer in the cDNA synthesis, the addition of single-sided PCR steps prior to the RACE-PCRs and the optimization of the dA-tailing reaction conditions…

Association of a variant in the muscarinic acetylcholine receptor 2 gene (CHRM2 ) with nicotine addiction

Genetic factors contribute to the overall risk of developing nicotine addiction, which is the major cause of preventable deaths in western countries. However, knowledge regarding specific polymorphisms influencing smoking phenotypes remains scarce. In the present study we provide evidence that a common single nucleotide polymorphism (SNP) in the 5′ untranslated region of CHRM2, the gene coding for the muscarinic acetylcholine receptor 2 is associated with nicotine addiction. CHRM2 was defined as a candidate gene for nicotine addiction based on previous evidence that linked variations in CHRM2 to alcohol and drug dependence. A total of more than 5,500 subjects representative of the German po…

The TPH intron 7 A218C polymorphism and TCI dimension scores in alcohol-dependent patients: hints to nonspecific psychopathology

Abstract Aims A linkage of certain alleles of the tryptophan hydroxylase (TPH) intron 7 A218C polymorphism to suicidality and antisocial behaviour has been described. The aim of our study was to find any association between dimensions of the Temperament and Character Inventory (TCI) indicating impulsivity and the TPH polymorphism alleles in unselected alcohol-dependent patients and age-matched controls. Methods We examined 159 alcohol-dependent patients and 161 controls with the TCI and genotyped them for the TPH intron 7 A218C polymorphism alleles. Results Although homozygous TPH genotypes were found more often in alcohol-dependent patients than in controls, an association between TCI dime…

Association of Low Striatal Dopamine D2Receptor Availability With Nicotine Dependence Similar to That Seen With Other Drugs of Abuse

All drugs of abuse induce a phasic dopamine release within the striatum that does not undergo habituation. Prolonged substance consumption impairs the natural function of the mesolimbic dopamine system, as shown by a decrease in the availability of striatal dopamine 2 (D(2)) receptors in patients suffering from cocaine, heroin, amphetamine, and alcohol dependence. However, it is unclear whether similar changes can also be observed in heavy-smoking nicotine-dependent smokers.In vivo D(2)/D(3) receptor availability was determined with [ (18)F]fallypride positron emission tomography in 17 heavy-smoking nicotine-dependent subjects and in 21 age-matched never-smoking comparison subjects. The smo…

Stimulation of immediate early gene expression by desipramine in rat brain.

The stimulation of immediate early gene expression in brain and neuronal cell culture systems has been reported after various experimental paradigms such as chemiconvulsant-provoked seizures or specific drug applications. In particular, the induction of immediate early genes by adrenergic model substances has been demonstrated by several investigators. This report demonstrates that a single dose of desipramine (10 or 25 mg/kg), a classical tricyclic antidepressant drug acting on the adrenergic system, induced c-fos and zif268 expression in rat hippocampus without affecting c-jun. The observed immediate early gene response might reflect part of a signal transduction cascade involved in long-…