Sex-dependent decrease of sphingomyelinase activity during alcohol withdrawal treatment.

BACKGROUND: In vitro and in vivo studies have demonstrated the role of the acid sphingomyelinase (ASM) in pathophysiological processes and alterations in response to ethanol exposure. Cellular and plasmatic ASM activities are increased in male alcohol dependent patients and decrease during physical withdrawal. METHODS: Here, we analyzed the time course of ASM in male and also female acutely intoxicated patients during alcohol withdrawal and compared the activity levels to those under long-term maintenance treatment. Craving and further psychometric parameters were assessed by questionnaires. RESULTS: The gradual decrease of serum ASM was confirmed in males (p<0.001) and continued to lower activities in long-term patients (p=0.001). The trend was similar in females (p=0.178), although the initial enzyme activities were significantly lower (p=0.035). ASM activity strongly correlated with the body mass index in males. The initial ASM activity and its decline during the first two days were associated with the improvement in scores for the Beck depression inventory, the obsessive compulsive drinking and the withdrawal syndrome scales. CONCLUSION: These data support the potential of ASM as a biomarker for the course of withdrawal therapy in males and provide the first associations of this enzyme with psychological variables such as craving and depression.

CB1 and CB2 receptor expression and promoter methylation in patients with cannabis dependence.

CB1 and CB2 receptors are influenced via exogenous and endogenous cannabinoids. To date, little is known regarding changes in receptor expression and methylation in THC (tetrahydrocannabinol) dependence. Therefore, the CB1 and CB2 receptor mRNA expression levels and promoter methylation status in the peripheral blood cells of 77 subjects (36 with THC dependence, 21 cigarette smokers and 20 nonsmokers) were assessed by quantitative real-time PCR and methylation-specific PCR. There was a significant difference in CB1 receptor expression levels between the three groups (ANOVA, p < 0.001, d.f. = 2, F = 71.3). The mean promoter methylation (%) was significantly negatively correlated with CB1 receptor mRNA expression levels (Spearman's rho: r = -0.37; p = 0.002). Using a mixed general linear model, it was demonstrated that the CB1 mRNA expression (as the dependent variable) was associated with the satisfaction with life scale (SWLS) (r = 0.101; T = 2.8; p = 0.007), craving (as measured with the VAS; r = -0.023; T = -2.3; p = 0.023) and the WHO-Assist Subscale for Cannabis consumption (r = -0.068; T = -2.4; p = 0.02). CB1 receptor expression levels and methylation status appear to be altered in subjects with THC dependence.

Auricular transcutaneous electrical nerve stimulation in depressed patients: a randomized controlled pilot study.

Invasive vagus nerve stimulation has been demonstrated to be an effective treatment in major depressive episodes. Recently, a novel non-invasive method of stimulating the vagus nerve on the outer canal of the ear has been proposed. In healthy subjects, a prominent fMRI BOLD signal deactivation in the limbic system was found. The present pilot study investigates the effects of this novel technique of auricular transcutaneous electric nerve stimulation in depressed patients for the first time. A total of 37 patients suffering from major depression were included in two randomized sham controlled add-on studies. Patients were stimulated five times a week on a daily basis for the duration of 2 weeks. On days 0 and 14, the Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI) were assessed. In contrast to sham-treated patients, electrically stimulated persons showed a significantly better outcome in the BDI. Mean decrease in the active treatment group was 12.6 (SD 6.0) points compared to 4.4 (SD 9.9) points in the sham group. HAMD score did not change significantly in the two groups. An antidepressant effect of a new transcutaneous auricular nerve stimulation technique has been shown for the first time in this controlled pilot study. Regarding the limitations of psychometric testing, the risk of unblinding for technical reasons, and the small sample size, further studies are necessary to confirm the present results and verify the practicability of tVNS in clinical fields.

Orexin A expression and promoter methylation in patients with cannabis dependence in comparison to nicotine-dependent cigarette smokers and nonsmokers.

BACKGROUND: The orexins (hypocretins) are neuropeptides with an origin in the lateral hypothalamus. They have been found to be crucial within the context of drug craving, withdrawal und relapse. METHODS: Therefore, orexin A gene expression and promoter methylation in peripheral blood cells of 77 subjects [36 with tetrahydrocannabinol (THC) dependence, 20 nicotine-dependent cigarette smokers and 21 nonsmokers] were assessed by quantitative real-time PCR and methylation-specific digestion PCR. RESULTS: There was a statistically significant difference in orexin A expression between the three groups [p = 0.000, F = 131.4, d.f. = 2, analysis of variance (ANOVA)]. Orexin A gene expression was statistically significantly correlated with the Satisfaction with Life Scale (r = -0.28, p = 0.018), a visual analogue scale of craving (r = 0.734, p = 0.000) and three subscales of the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test, i.e. nicotine consumption (r = 0.388, p = 0.001), alcohol consumption (r = 0.354, p = 0.002) and cannabis consumption (r = 0.783, p = 0.000). The mean promoter methylation (as a percentage) was not statistically related to orexin gene expression. However, there was a statistically significant difference in promoter methylation with regard to body mass index in general (F = 2.37, d.f. = 54, p = 0.016, ANOVA). CONCLUSIONS: Orexin might be a possible target in THC as well as nicotine dependence, taking into account the effect of THC on energy homeostasis in the circuit of reward and motivation and its impact on appetite and body weight.

Orexin A expression and promoter methylation in patients with alcohol dependence comparing acute and protracted withdrawal.

The orexins (hypocretins) are neuropeptides deriving from the lateral hypothalamus and may be of importance within the context of drug craving, withdrawal, and relapse. Therefore, the orexin A expression and promoter methylation in peripheral blood cells of 68 patients (41 male and 27 female patients at three different time points during withdrawal and 27 patients during stationary dehabituation therapy) suffering from alcohol dependence were assessed by quantitative reverse transcription-polymerase chain reaction and bisulfite sequencing. There was a statistically significant difference of orexin A expression between the three time points of withdrawal and long-term (LT) abstinence (F=4.16, P=.011). This difference was most prominent in comparison with LT abstinence (t=-3.08, P=.0032). Expression was significantly associated with the severity of withdrawal symptoms measured with the Withdrawal Syndrome Scale for Alcohol and Related Psychoactive Drugs (WSA) (t=2.17, P=.0356). The stronger the withdrawal symptoms, the lower the orexin A expression (F=4.69, P=.036). Body mass index (t=2.15, P=.041), the severity of withdrawal measured with the WSA (t=2.595, P=.0133), craving measured either by the Obsessive Compulsive Drinking Scale (t=2.77, P=.0085) or the Lübecker Craving Questionnaire (t=-2.23, P=.0314) had a significant influence on orexin A expression taking into account mean methylation of the CpG island of the orexin A promoter during withdrawal. Orexin A may be a possible candidate to further elucidate mechanisms of alcohol withdrawal taking into account energy homoeostasis in the circuit of reward and motivation.

Low digit ratio 2D:4D in alcohol dependent patients.

The ratio of the lengths of the second and fourth finger (2D∶4D) has been described as reflecting the degree of prenatal androgen exposure in humans. 2D∶4D is smaller for males than females and is associated with traits such as left-handedness, physical aggression, attention-deficit-hyperactivity disorder and a genetic polymorphism of the androgen receptor. All of these traits are known to be correlated to the vulnerability for alcohol dependency. We therefore hypothesized low 2D∶4D in patients with alcohol dependency. In the present study on 131 patients suffering from alcohol dependency and 185 healthy volunteers, we found that alcohol dependent patients had smaller 2D∶4D ratios compared to controls with preserved sexual dimorphism but with reduced right-left differences. The detection of alcohol dependency based on 2D∶4D ratios was most accurate using the right hand of males (ROC-analysis: AUC 0.725, sensitivity 0.667, specificity 0.723). These findings provide novel insights into the role of prenatal androgen exposure in the development of alcohol dependency and for the use of 2D∶4D as a possible trait marker in identifying patients with alcohol dependency.

The TTTAn aromatase (CYP19A1) polymorphism is associated with compulsive craving of male patients during alcohol withdrawal.

Alcoholism is associated with alterations of the hypothalamus-pituitary-gonadal hormone axis. We recently reported a leptin-mediated relation between the CAGn polymorphism of the androgen receptor and craving during alcohol withdrawal. This study investigated whether the TTTAn polymorphism of the aromatase (CYP19A1) is equally linked to craving. An association between TTTAn and compulsive craving (p=0.029) was revealed in our sample of 118 male alcohol addicts at day of hospital admission. Genotype-dependent subgroups showed differences in that the patients with short alleles suffered from lower compulsive craving during withdrawal than those with the longer alleles (p=0.027). The additional inclusion of leptin revealed no further significant association in the present study. Our finding is a further step on the way to elucidate the genesis of craving for alcohol with its extensive underlying interactions of different genetic and non-genetic factors. Future investigations should enrol women and consider sex hormone levels for further clarification of the observed TTTAn-craving relationship.

NGF plasma levels increase due to alcohol intoxication and decrease during withdrawal.

Recent studies show that alcohol dependence is associated with alterations in plasma levels of nerve growth factor (NGF). The aim of this study was to further elucidate reported alterations in NGF plasma levels during alcohol intoxication and withdrawal. Therefore, we assessed NGF plasma levels by enzyme-linked immunosorbent assay (ELISA) on admission (day 0) and day 7 of alcohol withdrawal in male alcohol dependent patients (n=75) in comparison to healthy controls (n=44). We found significant higher (U=1005.0, p<0.001) NGF plasma levels in the alcohol-dependent patients. Subgroup analysis showed significant higher (U=-2.934, p=0.003) NGF plasma levels in patients suffering from acute alcohol intoxication (group A) than in early abstinent patients (group B). From day 0 to day 7 of alcohol withdrawal NGF plasma levels decreased significantly in both groups (group A: Z=-3.118, p=0.002, group B: Z=-2.103, p=0.035). Our results suggest that acute alcohol intoxication is associated with an increase in NGF plasma levels, which decrease during alcohol withdrawal. These results suggest that NGF plasma levels increase as part of a regulation mechanism that counteracts alcohol intoxication.

Alcoholism, craving, and hormones: the role of leptin, ghrelin, prolactin, and the pro-opiomelanocortin system in modulating ethanol intake.

Evidence is growing that appetite regulating peptides such as leptin and ghrelin, but also other hormones including prolactin are altered in alcoholism. The brain pro-opiomelanocortin (POMC) system which has important mediating roles in alcohol intake also has important functions in prolactin regulation and energy homeostasis. Furthermore, it has been demonstrated to be functionally integrated with leptin regulation. The satiety factor leptin seems to be counteracted by the gut-derived peptide ghrelin which increases hunger and food intake. Consequently, the POMC system may have a role in integrating regulation of alcohol effects and these seemingly disparate regulatory systems. The goal of this mini-review is to discuss the results of some recent investigations of the potential interactions of these systems with acute and chronic alcohol responses.

Association of the long allele of the 5-HTTLPR polymorphism with compulsive craving in alcohol dependence.

AIMS: Various studies have reported a role of the serotonin transporter-linked polymorphic region (5-HTTLPR) in alcoholism. METHOD: The present study investigated an association of this polymorphism with obsessive-compulsive alcohol craving in 124 male patients admitted for alcohol detoxification treatment. RESULTS: We found significantly higher compulsive craving in patients with the long allele of the 5-HTTLPR polymorphism [at admission: analysis of variance (ANOVA): F = 3.48, P = 0.034, general linear model: F = 3.92, P = 0.023; after 7 days: ANOVA: F = 3.12, P = 0.049]. CONCLUSIONS: Our results suggest that the long variant of the 5-HTTLPR polymorphism is associated with higher compulsive alcohol craving at the beginning of alcohol withdrawal.

Combinations of carbohydrate-deficient transferrin, mean corpuscular erythrocyte volume, gamma-glutamyltransferase, homocysteine and folate increase the significance of biological markers in alcohol dependent patients.

AIMS: The traditionally used biological markers for alcoholism include a wide range of sensitivity and specificity as single tests. This study focuses on the combination of established laboratory parameters with new meaningful biomarkers to advance the significance regarding alcohol dependence. DESIGN: We analyzed blood samples from alcohol-dependent patients (n=177) compared with a control group (n=181). In the statistical calculation we included carbohydrate-deficient transferrin (CDT), mean corpuscular erythrocyte volume (MCV), gamma-glutamyltransferase (GGT), total plasma homocysteine, and folate. RESULTS: None of the examined biomarkers reached sensitivity above 90% while all markers showed a good specificity. Combinations of different markers led to a significant elevation in sensitivity. Best values for men were achieved by using a combination of MCV, CDT, GGT, homocysteine and folate in different weightings (sensitivity: 98.6%, specificity: 86.4%). For women, similar results were yielded by combining MCV and CDT (sensitivity: 94.1%, specificity: 96%). The addition of homocysteine and folate in different weightings did not result in further enhancement. CONCLUSIONS: Gender-specific clusters including MCV, CDT, GGT, homocysteine and folate led to an increase in sensitivity compared to single laboratory markers. This is a reliable help to identify patients with regular heavy drinking in clinical practice which might prevent further complications.

Apolipoprotein E gene polymorphism and previous alcohol withdrawal seizures.

Aim of this study was to investigate the possible association of apolipoprotein E (ApoE) gene polymorphism with a history of alcohol withdrawal seizures. We included 194 patients with alcohol dependence who were divided into patients with (SZ+) and without (SZ-) previous alcohol withdrawal seizures. ApoE genotypes were determined using PCR. For statistical analysis we examined the number of ApoE alleles (ApoE2: n=36; ApoE3: n=311; ApoE4: n=41). A significant positive association with a positive history of withdrawal seizures (SZ+) was found in the ApoE3 allele group (Fisher's exact test: p=0.006) while a significant negative association was observed in the ApoE2 allele group (Fisher's exact test: p=0.029). For the ApoE4 allele group no significant differences were found regarding a history of withdrawal seizures. Our findings suggest an association between the apolipoprotein E3 gene variant and an elevated risk of alcohol withdrawal seizures. These preliminary results must be validated in further studies.

Elevated prolactin serum levels and history of alcohol withdrawal seizures.

BACKGROUND: Prolactin has been discussed to be useful for differential diagnosis in epilepsia. Aim of the present study was to investigate the association between prolactin serum levels and previous alcohol withdrawal seizures. METHODS: We assessed 118 male patients admitted for detoxification treatment. Previous withdrawal seizures were recorded and prolactin serum levels were measured using an enzymatic immunoassay. RESULTS: Patients with a history of alcohol withdrawal seizures had significantly higher prolactin levels (17.8 ng/ml, SD=12.1) than patients without previous seizures (13.0 ng/ml, SD=8.1, p<0.05). Logistic regression revealed significant predictive qualities for prolactin serum levels (B=0.05, Wald=5.30, p=0.021, OR=1.06, 95%CI=1.01-1.11). CONCLUSIONS: The present findings show an association between elevated prolactin serum levels and a history of withdrawal seizures. Hence, the results suggest that prolactin elevation at admission may be a clinical marker for an increased risk of withdrawal seizures.

Obsessive-compulsive alcohol craving is not associated with Apolipoprotein E genotype.

This study examined a possible association with obsessive and compulsive alcohol craving in 192 alcohol-dependent patients undergoing detoxification treatment. Statistical analysis revealed no significant association between Apolipoprotein E polymorphism and obsessive-compulsive alcohol craving (analysis of variance: F=1.11, P=0.358).

Nicotine dependence is associated with compulsive alcohol craving.

AIMS: To investigate a possible association of nicotine dependence and alcohol craving. DESIGN: A prospective cross-sectional study on patients diagnosed with alcohol dependence. SETTING: Detoxification unit of a regional psychiatric hospital. PARTICIPANTS: A total of 127 smoking male patients were included in the study at admission for detoxification from alcohol. MEASUREMENTS: The Fagerström Test for Nicotine Dependence (FTND) was used to assess the severity of nicotine dependence while the Obsessive Compulsive Craving Scale (OCDS) was used to measure alcohol craving. The OCDS was assessed at admission and after 7 days of withdrawal treatment, distinguishing the total score, the obsessive and the compulsive subscale. FINDINGS: Spearman's correlation revealed a significant association between the extent of alcohol craving and the FTND score (day 0, n = 127: OCDS total score r = 0.238, P = 0.007; OCDS compulsive score r = 0.280, P = 0.001; day 7; n = 94: OCDS total score r = 0.212, P = 0.040; OCDS compulsive score r = 0.225, P = 0.029). CONCLUSIONS: The severity of nicotine dependence is associated with higher craving in alcohol-dependent patients. These results point towards shared pathophysiological mechanisms in alcohol craving and nicotine addiction.

An assessment of the potential value of elevated homocysteine in predicting alcohol-withdrawal seizures.

PURPOSE: Higher homocysteine levels were found in actively drinking patients with alcohol dependence. Recent studies have shown that high homocysteine levels are associated with alcohol-withdrawal seizures. The aim of the present study was to calculate the best predictive cutoff value of plasma homocysteine levels in actively drinking alcoholics (n = 88) with first-onset alcohol-withdrawal seizures. METHODS: The present study included 88 alcohol-dependent patients of whom 18 patients had a first-onset withdrawal seizure. All patients were active drinkers and had an established diagnosis of alcohol dependence, according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Sensitivity and specificity were calculated by using every homocysteine plasma level found in the study population as cut-off value. A Bayes theorem was used to calculate positive (PPV) and negative (NPV) predictive values for all cutoff values used. RESULTS: The highest combined sensitivity and specificity was reached at a homocysteine plasma cutoff value of 23.9 microM. Positive predictive values ranged from 0.23 to 0.745; the maximum was reached at a homocysteine plasma level of 41.7 microM. Negative predictive values ranged from 0.50 to 0.935, with a maximum at a homocysteine plasma level of 15.8 microM. CONCLUSIONS: Homocysteine levels above this cutoff value on admission are a useful screening tool to identify actively drinking patients at higher risk of alcohol-withdrawal seizures. This pilot study gives further hints that biologic markers may be helpful to predict patients at risk for first-onset alcohol-withdrawal seizures.

Different allele-distribution of mthfr 677 C -> T and mthfr -393 C -> a in patients classified according to subtypes of Lesch's typology.

AIMS: The typology by Lesch distinguishes between four subtypes: type 1 (model of allergy), type 2 (model of anxiety or conflict), type 3 (alcohol as an antidepressant), and type 4 (alcohol as adaptation). Taking into account that alcohol dependence is associated with elevated homocysteine levels, this study was undertaken to investigate different MTHFR (methylenetetrahydrofolate reductase) genotypes related to homocysteine metabolism in patients with alcohol dependence who were classified according to Lesch's typology (LT). SUBJECTS AND METHODS: 134 non-abstinent chronic alcoholics (112 males, 22 females; mean age 44.2 (SD 8.9) years) were classified according to LT and divided into four groups: LT 1 (n = 26), LT 2 (n = 65), LT 3 (n = 58), and LT 4 (n = 18). Total plasma homocysteine levels and MTHFR genotypes -393, 677, and 1,793 were determined. RESULTS: We observed a significantly higher frequency of the thermolabile MTHFR 677 C-->T variant (TT) in patients classified as subtype LT4 when compared with subtypes LT2 and LT3 (P = 0.005). Furthermore, for the MTHFR -393 C --> A-polymorphism, significantly more AC/AA variants were found in subtype LT4 (P = 0.034). No differences in allele-distribution were detected for MTHFR 1793. CONCLUSION: To our knowledge, this is the first study evaluating MTHFR genotypes in patients who were classified according to LT. Significantly different distributions of MTHFR 677 and -393 variants within Lesch Type 4 as compared with Types 2 and 3 hint at genetic determination of Lesch subtypes.

Prolactin serum levels and alcohol craving - an analysis using Lesch's typology.

BACKGROUND: Prolactin secretion is closely connected to dopaminergic transmission that is known to play a crucial role in mediating reinforcement and craving in alcoholism. OBJECTIVES: The study was performed to analyze the association between prolactin serum levels and alcohol craving during withdrawal differentiating alcohol-dependent patients using Lesch's typology. METHODS: We assessed 115 male patients with the Obsessive Compulsive Drinking Scale at early alcohol withdrawal. In addition, serum was obtained to measure prolactin concentration and the patients were classified according to Lesch's typology into one of four subgroups. RESULTS: Correlation analysis showed a significant association between prolactin serum levels and the extent of craving in Lesch's type 2 patients (r=0.32, p=0.015; n=57); however, no association was found for any other subgroup. The results were confirmed comparing patients with low and high craving (Mann-Whitney U test: Z=-2.805, p=0.005). CONCLUSIONS: In patients of Lesch's type 2, who are characterized to suffer from anxiety and to use alcohol because of its anxiolytic effects, prolactin is associated with craving during early alcohol withdrawal.

Recurrent detoxifications are associated with craving in patients classified as type 1 according to Lesch's typology.

AIMS: Recurrent detoxifications have been suggested to be associated with elevated alcohol craving. The aim of this investigation was to study the influence of preceding detoxifications on craving in patients with alcoholism classified according to Lesch's typology. METHODS: We examined 192 patients (154 men, 38 women) after admission for detoxification treatment. Craving was assessed using the Obsessive Compulsive Drinking Scale, and patients were classified into one of the four subgroups of Lesch's typology. The number of preceding detoxifications was assessed with a structured interview. RESULTS: Lesch's typology type 4 patients showed significantly higher craving scores than type 1-3 patients (Mann-Whitney U-Test; P < 0.05). With respect to the influence of recurrent detoxifications, we found a significant correlation between the number of preceding detoxifications and the extent of craving for the whole population (Spearman's rho r = 0.241, P = 0.001, N = 192), particularly for patients of Lesch's type 1 (Spearman's rho r = 0.534, P = 0.001, N = 37). No significant association was found for patients of the other subgroups (Lesch's type 2-4). CONCLUSION: The influence of recurrent detoxifications on craving is especially important in patients with Lesch's type 1. Our results underline the importance of the kindling effect particularly in this group of patients, possibly mediated by an increase of glutamatergic neurotransmission. Furthermore, our results emphasize the need to classify patients with alcohol-dependency in addiction research.

Volume intake and craving in alcohol withdrawal.

AIMS: It has been shown that beer consumption is associated with alcohol craving, in contrast to wine or spirits consumption. The present study was undertaken to evaluate whether the daily volume intake of alcoholic beverages is associated with craving in patients undergoing alcohol withdrawal. METHODS: A total of 158 male patients were assessed using the obsessive compulsive drinking scale (OCDS) at admission. The daily volume intake of alcoholic beverages was calculated by adding the volume of all regularly consumed alcoholic beverages, disregarding their alcohol percentage. Lesch's typology was used to classify patients for subgroup analysis. RESULTS: The daily volume intake of alcoholic beverages correlated significantly with the extent of the OCDS (r = 0.33; P < 0.001). With general linear models, we found a significant association of the calculated daily volume intake of all alcoholic beverages with craving (F = 6.426; P = 0.012), but not for the daily ethanol intake. Differentiating the patients according to Lesch's typology a significant association was particularly found in Lesch Type 2 (model of anxiety) patients (F = 11.31; P = 0.001). CONCLUSION: Our results support the hypothesis that volume intake is associated with craving and suggest a role of pathophysiological changes in volume regulating mechanisms (such as vasopressin or ANP) in the neurobiology of alcohol craving, particularly in male patients of Lesch's Type 2 undergoing alcohol withdrawal.