Introduction: DNA methylation constitutes one important epigenetic mechanism that regulates gene expression in human cells. With regard to obesity, bariatric surgery-induced weight loss has been associated with promoter methylation changes in several genes. Hyperleptinemia is a characteristic feature of obesity. The underlying regulating mechanisms have not yet been completely elucidated. Methods: We investigated the methylation of the promoters of the leptin gene (LEP) and the leptin receptor gene (LEPR) as well as leptin expression in pre- and postbariatric surgery patients using a comparative cross-sectional design. Results: Our results revealed significantly higher LEP promoter methylation patterns in prebariatric surgery patients compared to postoperatively. DNA methylation of the LEPR promoter was significantly higher in the postoperative group. Moreover, we found significantly higher leptin serum levels in patients before the bariatric surgery than afterwards. Discussion: These findings strengthen the suggestion that there is an association between LEP expression and LEP methylation in obesity. We suggest that the epigenetic profile of LEP might be influenced by leptin serum levels in the form of a regulating feedback mechanism.

The dopaminergic neurotransmission is known to be of crucial importance in addictive behavior. Epigenetic regulation like methylation of DNA influences the function of dopaminergic transmission. The present study investigated alterations of DNA methylation in the dopamine D2 receptor (DRD2)-gene in patients suffering from alcohol dependence. The study sample consists of 99 alcohol dependent males admitted for alcohol withdrawal treatment and a control group of 33 healthy participants. Blood samples underwent bisulfite sequencing to determine levels of DNA-methylation of the promoter region of the DRD2 gene. Mixed linear modeling was used to test differences between patients and controls, course of methylation during detoxification. While DRD2-gene methylation did not differ significantly between patients and controls, we found a significant increase of DRD2-gene methylation during alcohol withdrawal/early abstinence. Craving, measured with the Obsessive Compulsive Drinking Scale (OCDS), was significantly associated with DRD2-gene methylation. Furthermore, smoking significantly influenced DRD2-gene methylation in both, patients and controls. As in other types of addictive disorders, DRD2-gene methylation is altered during alcohol withdrawal/early abstinence. The findings regarding an association with alcohol craving and tobacco consumption point towards a crucial role of DRD2-gene methylation in the neurobiology of addictive behavior.

Purpose: The aim of this study was to investigate the effects of bariatric surgery on homocysteine serum levels with respect to cognitive functioning and level of depression. Materials and Methods: Fasting homocysteine, vitamin B12, and folate levels were measured in 99 patients; 48 bariatric surgery candidates and 51 postbariatric patients with a mean excess weight loss of at least 40%. Cognitive performance in all subjects was evaluated by a computerized test battery. Depression was assessed using the depression module of the Patient Health Questionnaire. Results: We found a significant relationship between gender, folate, and affiliation and the pre/postgroup and homocysteine levels. Postoperative patients' homocysteine levels were significantly higher compared with preoperative levels. Regarding cognitive functioning, bivariate correlations suggested a link between homocysteine and verbal learning/short-term memory, measured with the Auditory Verbal Learning Test as a trend, not reaching significance. Multivariate analysis showed that it was not homocysteine but affiliation to the pre- or postoperative group that was significantly associated with the level of depression. Applying the Auditory Verbal Learning Test as a dependent variable, male gender and younger age were associated with better task performance, but homocysteine was not. Conclusions: Our results do not support a relevant pathophysiological role of homocysteine levels in cognitive performance early after bariatric surgery.

Alcohol-withdrawal seizures (AWS) are an important and relevant complication during detoxification in alcohol-dependent patients. Therefore, it is important to evaluate the individual risk for AWS. We apply a random forest algorithm to assess possible predictive markers in a large sample of 200 alcohol-dependent patients undergoing alcohol withdrawal. This analysis showed that the combination of homocysteine, prolactin, blood alcohol concentration on admission, number of preceding withdrawals, age and the number of cigarettes smoked may successfully predict AWS. In conclusion, the results of this analysis allow for origination of further research, which should include additional biological and psychosocial parameters as well as consumption behaviour.

Aims: Alcohol withdrawal seizures (AWS) are among the most important possible complications during the detoxification treatment of alcohol-dependent patients. Pharmacological therapy is often used during detoxification, but can cause dangerous side effects [Eur Addict Res 2010;16:179–184]. In separate studies several biological markers have been described as being associated with AWS risk. We investigated the role of homocysteine (HCT), carbohydrate-deficient transferrin (CDT) and prolactin (PRL) as biological markers for the risk of developing AWS. Methods: The present study included 189 alcohol-dependent patients of whom 51 had a history of AWS. We investigated the HCT, CDT and PRL levels of all patients and calculated sensitivity and specificity. Bayes’ theorem was used to calculate positive (PPV) and negative (NPV) predictive values. Results: The highest combined sensitivity and specificity for %CDT was reached at a plasma cutoff value of 3.75%. The combination of HCT at a cutoff value of 23.9 µmol/l and %CDT at a cutoff value of 3.75% showed the best predictive values (sensitivity 47.1%, specificity 88.4%, PPV 0.504, NPV 0.870). Conclusion: A combined assessment of HCT and CDT levels can be a useful method to identify patients at a higher risk of AWS, which may lead to a more individualized therapy.

Gray matter abnormalities have been found in anorexia nervosa (AN) in several brain regions. However, little is known about white matter abnormalities under the condition of AN. To comprehensively assess the microstructural integrity of white matter pathways in women with anorexia nervosa, we performed voxel-based Diffusion Tensor Imaging (DTI). 21 women with AN according to DSM-IV criteria (9 of them recovered) and 20 female age-matched healthy control subjects were enrolled in the study. The patients had a mean body mass index of 17.2 kg/m2 (controls: 19.6 kg/m2). High resolution T1 images (MP-RAGE) and DTI were performed on a 3 T Siemens-scanner. Images were pre-processed and analyzed using a modified protocol for DTI in SPM2. Fractional anisotropy (FA) maps were compared using t-tests (p < 0.05, corrected). Compared with controls, AN patients showed bilateral reductions of FA maps in the posterior thalamic radiation which includes the optic radiation, and the left mediodorsal thalamus. Our study is limited by the small sample size and its cross-sectional design. A longitudinal design with the same individuals assessed when acutely ill and recovered is warranted for future studies. For the first time, the findings of our DTI study identified disturbances of associational and commissural fibers in the bilateral occipitotemporal white matter. The results help narrowing the prevailing biological models of AN by suggesting that body image distortion is related to microstructural alterations of white matter tracts connecting the extrastriate visual cortex with other brain regions involved in body perception.

Background: The hypothalamic galanin expression has been associated with increased intake of carbohydrates and fats in preclinical studies. The appetite stimulating effect of galanin is thought to underlie the positive association between alcohol consumption and hypothalamic galanin expression observed in preclinical studies.Methods: In this pilot study we investigated alterations in galanin serum levels (33 male patients) in alcohol-dependent patients during alcohol withdrawal (days 1, 7 and 14) in comparison to healthy controls (19 male controls). In order to assess the putative association between appetite regulation, galanin serum levels and alcohol consumption we additionally investigated the serum levels of insulin, glucose and triglycerides.Results: The galanin serum levels on day 1 of alcohol withdrawal were significantly reduced in the alcohol-dependent patients (T=-3.302, p=0.002) and increased significantly from day 1 to day 14 of alcohol withdrawal (F=6.437, p=0.002). We found a significant negative association between the galanin serum levels and alcohol craving measured by the Obsessive Compulsive Drinking Scale (OCDS) (r=-0.449, p=0.009) and the obsessive subscale of the OCDS (r=-0.521, p=0.002) on day 1 of alcohol withdrawal. There was no association between the galanin serum levels and the parameters of energy homeostasis (triglycerides, cholesterol, insulin, and glucose) investigated.Conclusions: Acute alcohol withdrawal was associated with decreased galanin serum levels in this pilot study. There was no association between the galanin serum levels and the parameters of energy homeostasis. Further research of galanin serum levels in active drinkers will be necessary to clarify the putative association between galanin serum levels, appetite regulation-and alcohol consumption. (C) 2010 Elsevier Inc. All rights reserved.

ABSTRACTWe investigated the Cytosin‐phosphatidyl‐Guanin (CpG) island promoter methylation (mean and methylation of individual CpG‐sites) of the nerve growth factor (NGF) gene in the blood of alcohol‐dependent patients (57 male patients) during withdrawal (days 1, 7 and 14). Methylation and NGF serum levels did not change significantly from days 1–7. From days 7–14, mean methylation increased (F = 30.55, P < 0.001), whereas the NGF serum levels decreased significantly (days 7–14: F = 17.95, P < 0.001). The NGF serum levels were significantly associated with the mean methylation of the investigated CpG‐sites (F = 1.55, P < 0.001). These results imply an epigenetic regulation of the NGF gene during alcohol withdrawal.

Introduction: The serotonergic system plays a role in the neurobiology of eating disorders. The serotonin transporter gene (SLC6A4) promoter polymorphism (5HTTLPR) was examined as a susceptibility gene for anorexia nervosa. DNA methylation of a CpG island upstream of the promoter region has been associated with childhood abuse and an interaction between 5HTTLPR genotype and methylation density was shown to predict unresolved loss or trauma. Methods: The aim of our study was to analyze 5HTTLPR genotype and SLC6A4 promoter methylation in a sample of in-patients with anorexia (n = 20) or bulimia nervosa (n = 22). Results: We found an effect of the 5HTTLPR on age of onset and on the Eating Disorder Inventory-2 subscales drive for thinness and body dissatisfaction. The methylation density of the 5‘ region of the promoter was associated with the BDI score and with binge eating behavior – the 3’ region was associated with purging and self-injuring behavior. In a general linear model computing several phenotypic characteristics as dependent and genotype and methylation as independent variables, whole model significance could be reached for BDI, self injuring behavior, age at onset, years of illness and drive for thinness. Conclusions: Our study shows that analysis of different regulatory mechanisms, i.e. genotype and promoter methylation together can help to explain phenotypic variability that could not be accounted for by one factor alone.

Preclinical study results suggest that brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) modulate addictive behaviour. Therefore we investigated alterations in BDNF (81 male patients) and GDNF serum levels (52 male patients) in alcohol-dependent patients during alcohol withdrawal (day 1, 7 and 14) in comparison to healthy controls (41 male controls). BDNF serum levels were not significantly altered in alcohol-dependent patients compared to healthy controls (p=0.685). GDNF serum levels were significantly reduced in the alcohol-dependent patients (p<0.001). BDNF (p=0.265) and GDNF (p=0.255) serum levels did not change significantly during alcohol withdrawal. BDNF serum levels were significantly negatively associated with alcohol withdrawal severity on day 1 (CIWA-Ar score, p=0.004). GDNF serum levels were significantly negatively associated with individual estimation of alcohol tolerance (SESA-XT score, p=0.028). There was no further association with psychometric dimensions of alcohol withdrawal. In conclusion we found that GDNF serum levels are significantly reduced in alcohol-dependent patients. GDNF serum levels were negatively associated with alcohol tolerance. Moreover BDNF serum levels were found to be associated with withdrawal severity.

Recent studies have shown elevated homocysteine levels in patients with eating disorders. In a prospective, longitudinal study, we investigated differences of homocysteine plasma levels in patients with anorexia nervosa (N = 12) and bulimia nervosa (N = 17) compared to healthy controls (N = 20) and alteration of homocysteine levels in patients during specific in-patient treatment. We found significantly elevated homocysteine levels in both patient groups (anorexia nervosa and bulimia nervosa) and a non-significant decrease of homocysteine during the 12-week treatment period. Furthermore, we found a significant association between low homocysteine levels and cognitive deficits, pointing toward a beneficial effect of elevated homocysteine levels on cognition in this patient group. We suppose that during effective treatment with significant increase of the body mass index, the observed hyperhomocysteinemia in patients with eating disorders is partially reversible. These findings add further evidence to the hypothesis that homocysteine might be involved in the pathophysiology of anorexia and bulimia nervosa.

Disturbances of volume regulating peptides like vasopressin and atrial natriuretic peptide (ANP) have been described in early abstinent patients. Aim of the present study was to evaluate possible alterations of the promoter-related DNA methylation of the ANP and vasopressin precursor genes and the related mRNA-expression of these genes in early alcohol withdrawal. We analyzed blood samples of 57 healthy controls and of 111 patients suffering from alcohol dependence that were admitted for detoxification treatment. Promoter-related DNA methylation and mRNA-expression of vasopressin and ANP genes were assessed using real-time PCR. Vasopressin mRNA-expression was not statistically different between patients and controls. However, we found a significantly elevated promoter-related DNA methylation of the vasopressin gene in patients with alcohol dependence (Mann–Whitney U-test: Z = −2.178, p = 0.029). ANP mRNA-expression was significantly elevated in alcoholic patients (Z = −6.240, p < 0.001) while promoter-related DNA methylation of ANP was significantly decreased (Z = −2.282, p = 0.023). Furthermore, promoter-related DNA methylation of ANP was significantly correlated to the extent of craving measured with the OCDS (r = −0.197, p = 0.040). The findings of the present study show significant alterations of the mRNA-expression and promoter-related DNA methylation of vasopressin and especially ANP precursor genes in patients with alcohol dependence. Further studies focusing on longitudinal changes of epigenetic regulation and gene expression of both peptides are needed to clarify the pathophysiological role of these findings.

OBJECTIVEThe pathophysiology of eating disorders such as anorexia nervosa (AN) and bulimia nervosa (BN) has been linked to an impaired dopaminergic neurotransmission, still the origin of this disturbance remains unknown. The aim of the present study was, therefore, to evaluate whether the expression of dopaminergic genes is altered in the blood of patients suffering from eating disorders and if these alterations can be explained by changes in the promoter specific DNA methylation of the genes.METHODWe used quantitative real-time PCR to measure both the expression and the promoter specific DNA methylation of the dopamine transporter (DAT), and the D2 (DRD2) and D4 receptor (DRD4) gene in the blood of 46 patients (22 AN, 24 BN) and 30 healthy controls.RESULTSPatients showed an elevated expression of DAT mRNA when compared with the controls and a downregulation of the DRD₂ expression. The upregulation of the DAT gene was accompanied by a hypermethylation of the gene's promoter in the AN and BN group while a significant hypermethylation of the DRD₂ promoter was only present in the AN group. No differences in expression or methylation were found for the other dopamine receptors investigated.DISCUSSIONOur study shows a disturbed expression of dopaminergic genes that is accompanied by a dysregulation of the epigenetic DNA methylation. Further studies are necessary to provide more insight into the epigenetic dysregulation of the dopaminergic neurotransmission in the pathophysiology of eating disorders.

α-Synuclein (α-Syn) is a neuronal protein involved in the regulation of brain serotonin and dopamine levels. We analyzed the peripheral expression of α-Syn mRNA and Beck Depression Inventory scores in female patients suffering from anorexia nervosa (n = 18) or bulimia nervosa (n = 24). We found a significant positive association between α-Syn mRNA expression and the total scores of the Beck Depression Inventory (linear regression; R2 = 0.20; p = 0.003). α-Syn may play a pathophysiological role in depressive symptoms associated with eating disorders. Further investigations in patients with depression as a sole diagnosis are needed to support its role in the pathogenesis of major depression.

Disturbances of volume-regulating mechanisms have already been implicated in the pathophysiology of eating disorders like anorexia or bulimia nervosa with the peptide hormones vasopressin and atrial natriuretic peptide (ANP) being of special interest. Aim of the present study was to investigate, whether the expression of the corresponding genes was altered and if so, if these changes could be explained by epigenetic mechanisms such as DNA methylation. We analyzed blood samples of 46 women suffering from anorexia (n=22) or bulimia nervosa (n=24) as well as of 30 healthy controls. Peripheral mRNA expression and DNA methylation of the vasopressin and the ANP precursor genes were assessed using real-time PCR. We found significantly lower levels of ANP mRNA in patients with eating disorders. This downregulation was accompanied by a hypermethylation of the ANP gene promoter in the bulimic subgroup. We did not find differences regarding expression or methylation of the vasopressin gene. ANP mRNA expression was inversely associated with impaired impulse regulation. We conclude that epigenetic mechanisms may contribute to the known alterations of ANP homeostasis in women with eating disorders.

Dopaminergic neurotransmission plays a crucial role in the genesis and maintenance of alcohol dependence. Epigenetic regulation via promoter specific DNA methylation of the dopamine transporter gene (DAT) may influence altered dopaminergic neurotransmission in alcoholism. Aim of the present study was to investigate DNA promoter methylation of DAT in early alcohol withdrawal and in relation to alcohol craving. We analyzed blood samples of 76 patients admitted for detoxification treatment and compared them to 35 healthy controls. Methylation specific quantitative real-time PCR was used to measure the promoter specific DNA methylation of the dopamine transporter. We assessed the extent of alcohol craving using the obsessive compulsive drinking scale (OCDS). Compared to healthy controls we found a significant hypermethylation of the DAT-promoter (Mann-Whitney U-test: p=0.001). Ln-transformed methylation of the DAT-promoter was negatively associated with the OCDS (linear regression: Beta=-0.275, p=0.016), particularly with the obsessive subscale (Beta=-0.300, p=0.008). Findings of the present study show that the epigenetic regulation of the DAT-promoter is altered in patients undergoing alcohol withdrawal. Furthermore, hypermethylation of the DAT-promoter may play an important role in dopaminergic neurotransmission and is associated with decreased alcohol craving.

Objective: The endocannabinoid system is involved in the regulation of appetite, food intake and energy balance.Methods: To study possible differences in CB(1) and CB(2) mRNA expression in eating disorders, 20 patients with anorexia nervosa (AN), 23 with bulimia nervosa (BN) and 26 healthy women were enrolled into the trial (Homocysteine and Eating Disorders, HEaD).Results: We found significantly higher levels of CB, receptor mRNA in the blood of patients with AN (Delta CT: -3.9 (1.0); KW: 11.31; P = 0.003) and BN (Delta CT -3.7 (1.7)) when compared to controls (Delta CT. -4.6 (0.6); Dunn's test AN vs. Controls: P < 0.05; BN vs. Controls: P < 0.001) measured by quantitative real-time PCR. No differences were found regarding the expression of CB(2) receptor mRNA. Higher CB(1) receptor expression was associated with lower scores in several eating disorder inventory-2 (EDI-2) subscales including perfectionism, impulse regulation and drive for thinness.Conclusion: Our finding of elevated CB(1)-receptor expression in AN and BN adds further evidence to the hypothesis of impaired endocannabinoid signaling in eating disorders. (C) 2008 Elsevier Ltd. All rights reserved.

Aims: The individual extent of structural brain tissue changes in patients with alcohol dependence is influenced by genetic factors, gender, age and possibly a dose/duration-effect. Aim of the present study was to investigate different types of alcoholic beverages with regard to hippocampal volume loss in patients suffering from alcoholism. Methods: We included 52 patients with alcohol dependence and divided them according to their preferred type of beverage consumption (beer, wine, and spirits). Hippocampal volumes were determined using volumetric high-resolution MR imaging. Results: There was a significant difference in hippocampal volumes between patients consuming different beverages (ANOVA: F = 7.454; df = 2; P = 0.0015) with the smallest volumes in the wine group, followed by the spirits group. Furthermore, patients with a preferred spirits consumption showed significantly higher plasma homocysteine levels (ANOVA: F = 3.39; df = 2; P = 0.042). Linear regression analyses revealed an association of homocysteine and hippocampal volume only in the group of patients preferring spirits (R(2) = 0.364; P = 0.008). Conclusions: Homocysteine-mediated excitotoxicity may be an important pathophysiological mechanism in ethanol-related brain damage, particularly in patients consuming wine and spirits. The extent of brain atrophy in beer consuming patients seems to be more moderate.