Suchergebnisse

<i>Aims:</i> 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. <i>Methods:</i> 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. <i>Results:</i> 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). <i>Conclusion:</i> 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.

<b><i>Background:</i></b> Atrial natriuretic peptide (ANP) is well known in psychiatric disorders to modulate hypothalamic-pituitary-adrenal axis activity. Disturbances of ANP have been described in early abstinent alcohol-dependent patients. This is the first longitudinal investigation on cytosine-phosphatidyl-guanine (CpG)-island promoter methylation of the <i>ANP</i> gene in the blood of tobacco-dependent patients. <b><i>Methods:</i></b> In a longitudinal approach, we investigated whether changes in ANP serum levels correlated to CpG methylation of the respective gene promoters on days 1, 7, and 14 of tobacco withdrawal. <b><i>Results</i></b> <b><i>and Conclusion:</i></b> Compared to non-smokers, promoter-related deoxyribonucleic acid methylation of the ANP promoter was significantly elevated on days 7 and 14 of withdrawal in tobacco-dependent patients. Baseline methylation status of the ANP promoter was not significantly different from controls, arguing for an impaired regulation during withdrawal.

<b><i>Aims:</i></b> Childhood trauma is of importance for the manifestation of substance-related disorders and maintenance of hypothalamic-pituitary-adrenal (HPA)-axis disorders. Since stress plays a crucial role in opioid compliance and craving, we investigated the immediate effects of diacetylmorphine application on the HPA axis. In particular, adrenocorticotropic hormone (ACTH) and cortisol secretion, as well as satiety regulating proopiomelanocortin peptides α-melanocyte-stimulating hormone (MSH) and β-endorphin (END) in a cohort of opioid-dependent patients in diamorphine maintenance treatment concerning the clinical severity of their childhood trauma. <b><i>Methods:</i></b> We compared the serum levels of ACTH, cortisol, MSH, and END in 15 opioid-dependent patients. All participants received treatment with diamorphine and were observed at 5 timepoints before and after injection. We split the cohort into 2 subgroups concerning childhood trauma measured by the Childhood Trauma Questionnaire. <b><i>Results:</i></b> Splitting in 2 subgroups for mild (5) and severe trauma (10), we found that while both groups show a significant reduction of ACTH and cortisol levels over time, slopes display different progressions over time for cortisol (<i>F</i>[1.6] = 9.38, <i>p</i> = 0.02), while remaining identical for ACTH (<i>F</i>[1.6] = 1.69, <i>p</i> = 0.24). Also, levels of both MSH and END were significantly lower in severely traumatized patients. <b><i>Conclusions:</i></b> For the first time, we present a detailed representation of stress- and addiction-related proteins for the first 5 h after diamorphine application, demonstrating the interrelationship between stress hormones and childhood trauma as well as its potential effects on the progression of addictions such as opioid dependence.

Appetite-regulating peptides, such as leptin, are linked to craving and have been in the focus of alcohol dependence research for years. The objective of our study was to investigate the dynamics of leptin gene promoter methylation during alcohol withdrawal and specific treatment in a rodent (rat) model for alcohol dependence. DNA methylation was measured using direct bisulfite sequencing at 0 h, 24 h, and 6 days of alcohol withdrawal as well as after treatment with alpha-melanocyte-stimulating hormone (alpha-MSH), Beta-Endorphin, or saline. We found significantly lower methylation levels in alcohol-consuming animals compared to alcohol-naïve animals. During 6 days of alcohol deprivation, this difference in methylation vanished. Leptin methylation of the alpha-MSH-treated group and 6 days alcohol-deprived animals was significantly higher than that in saline-treated animals, possibly indicating compensatory effects of the treatment. Our results further expand on previous findings from human studies that explain leptin's role in bridging the gap between alcohol consumption and appetite regulation.

Abstract

Aims
Alcohol use alters the reward signaling processes contributing to the development of addiction. We studied the effects of alcohol use disorder (AUD) on brain regions and blood of deceased women and men to examine sex-dependent differences in epigenetic changes associated with AUD. We investigated the effects of alcohol use on the gene promoter methylation of GABBR1 coding for GABAB receptor subunit 1 in blood and brain.


Methods
We chose six brain regions associated with addiction and the reward pathway (nucleus arcuatus, nucleus accumbens, the mamillary bodies, amygdala, hippocampus and anterior temporal cortex) and performed epigenetic profiling of the proximal promoter of the GABBR1 gene of post-mortem brain and blood samples of 17 individuals with AUD pathology (4 female, 13 male) and 31 healthy controls (10 female, 21 male).


Results
Our results show sex-specific effects of AUD on GABBR1 promoter methylation. Especially, CpG −4 showed significant tissue-independent changes and significantly decreased methylation levels for the AUD group in the amygdala and the mammillary bodies of men. We saw prominent and consistent change in CpG-4 across all investigated tissues. For women, no significant loci were observed.


Conclusion
We found sex-dependent differences in GABBR1 promoter methylation in relation to AUD. CpG-4 hypomethylation in male individuals with AUD is consistent for most brain regions. Blood shows similar results without reaching significance, potentially serving as a peripheral marker for addiction-associated neuronal adaptations. Further research is needed to discover more contributing factors in the pathological alterations of alcohol addiction to offer sex-specific biomarkers and treatment.

Disturbances of volume-regulating peptides like vasopressin (AVP) and atrial natriuretic peptide (ANP) have been described in early abstinent alcohol-dependent patients. In a longitudinal approach, we investigated whether changes in AVP and ANP serum levels correlated to cytosine-phosphatidyl-guanine (CpG) methylation of the respective gene promoters on days 1, 7 and 14 of alcohol withdrawal. We analyzed the blood samples of 99 patients suffering from alcohol dependence alongside age- and BMI-matched controls. Concerning AVP promoter methylation, we observed an interaction between time of measurement and CpG loci with CpG 2 showing a significant increase in methylation from day 1 to 14. Serum levels of AVP were significantly decreased in the patient group. Compared to healthy controls, promoter-related DNA methylation of the ANP promoter was significantly reduced on days 7 and 14. Moreover, we detected a significant interaction between CpG position and group. In both cases the difference was mainly observed at CpG 1. The present study shows significant changes in the methylation status of individual CpG sites of AVP and ANP. Observing respective alterations of AVP serum protein levels in alcohol-dependent patients during detoxification treatment, we consider methylation as a possible mode of regulation for these proteins during alcohol detoxification.

Preclinical study results suggest that neurotrophic peptides like nerve growth factor (NGF) and vascular endothelial growth factor A (VEGF-A) may be associated with symptoms of addictive behavior like withdrawal symptoms and rewarding effects. We investigated alterations in NGF and VEGF-A serum levels in opiate-dependent patients (25 male patients), who received diamorphine (DAM, heroin) treatment within a structured opiate maintenance program, and compared the results with the NGF and VEGF-A serum levels of healthy controls (23 male controls). NGF and VEGF-A serum levels were assessed before and after DAM administration twice a day (in the morning (16 h after last application – t1) and in the afternoon (7 h after last application – t3)) in order to detect a possible immediate or summative (in the afternoon) heroin effect on these two neuropeptides. Moreover, we investigated possible associations between the serum levels of these neurotrophic growth factors and psychometric dimensions of addictive behavior, e.g. craving, withdrawal, depression. Whereas there was no direct effect of DAM application on the serum levels of both neurotrophic growth factors neither in the morning nor in the afternoon, the NGF serum levels of the patient group were found to be significantly increased at all four time points of investigation compared with the healthy controls. In contrast, VEGF-A serum levels did not differ significantly in the patient and control groups. We found a significant positive association between the NGF serum levels and several items of the short opiate withdrawal scale as well as a negative association between self-reported mood (measured by visual analogue scale) and mood before heroin application (in the morning as in the afternoon). Moreover, we found a significant positive association between the NGF serum levels (t1 and t3) and the self-reported craving for methadone. In contrast, we found a negative association between the VEGF-A serum levels and avoidance, anxiety, suicide intentions of the SCL-90 as well as a positive association between the VEGF-A serum levels and the subscales of the heroin craving questionnaire measuring the rewarding effects of heroin. In conclusion, the results of this pilot study show that there might be an association between symptoms of opiate dependence and withdrawal and serum levels of VEGF-A and NGF.

<b><i>Aims:</i></b> The nerve growth factor (NGF) and the vascular endothelial growth factor-A (VEGF-A) may be of importance for psychiatric diseases including substance use disorders. The aim of the study was to identify differences in the regulation of both neuropeptides via the DNA-methylation status of the promotor regions of NGF and VEGF-A in different forms of maintenance therapy for opioid dependence and the related stress regulation via the hypothalamic-pituitary-adrenal axis. <b><i>Methods:</i></b> We compared methylation levels of opioid-dependent patients receiving treatment with diamorphine (<i>n</i> = 28) or levomethadone (<i>n</i> = 54) and similar levels in a healthy control group (<i>n</i> = 72). <b><i>Results:</i></b> There was a significantly higher methylation of VEGF-A in opioid-maintained patients with levomethadone compared to that in the control group (estimated marginal means [EMM] [SE]): 0.036 [0.003] vs. 0.020 [0.003]; <i>p</i> &#x3c; 0.001). We performed a cluster analysis for NGF, splitting up the results in 4 clusters. We found significant changes in methylation rates of the opioid-maintained patients compared to the controls in cluster I ([EMM] [SE]: 0.064 [0.005] vs. 0.084 [0.006]; <i>p</i> = 0.03), cluster II ([EMM] [SE]: 0.133 [0.013] vs. 0.187 [0.014]; <i>p</i> &#x3c; 0.001) and cluster III ([EMM] [SE]: 0.190 [0.014] vs. 0.128 [0.016]; <i>p</i> &#x3c; 0.001). <b><i>Conclusions:</i></b> The results are of importance, as they indicate that long-term changes in stress regulation regulated by neurotrophines are a crucial part of the symptomatology of opioid dependence, thus influencing drug consumption and the different forms of opioid-maintenance therapies.

Acetaldehyde, the carcinogenic metabolite of ethanol known to provoke aversive symptoms of alcohol consumption, is predominantly eliminated by aldehyde dehydrogenase 2 (ALDH2). Reduced ALDH2 activity correlates with low alcohol tolerance and low risk for alcohol dependence. The ALDH2 promoter polymorphism rs886205 (A>G) is associated with decreased promoter activity, but a molecular mechanism and allele-dependent ALDH2 protein expression has not been described yet. On the basis of allele-dependent epigenetic effects, we analyzed the rs886205 genotype, methylation rates of cytosine-phosphatidyl-guanine (CpG)-sites within a regulatory promoter region and ALDH2 protein levels in 82 alcohol-dependent patients during a 2-week withdrawal and compared them to 34 matched controls. Patients without the G-allele of rs886205 showed higher methylation of the promoter region than controls and readily adapted epigenetically as well as on protein level during withdrawal, while patients with the G-allele displayed retarded methylation readjustment and no change in ALDH2 protein levels. Our data provide novel insights into an unknown genetic-epigenetic interaction, revealing impaired ALDH2 protein expression in patients with the G-allele of rs886205. Additionally, we checked for an association between rs886205 and protection against alcohol dependence and found a trend association between the G-allele and protection against alcohol dependence that needs replication in a larger Caucasian cohort.

AbstractAimsThe dopamine receptor D2 (DRD2) is substantially involved in several forms of addiction. In addition to genetic polymorphisms, epigenetic mechanisms have emerged as an important means of regulation. Previously, DRD2 hypo- and hyper-methylation have been observed in alcohol use disorder (AUD). Blood samples are commonly used as a surrogate marker of epigenetic alterations in epigenetic research, but few specific comparisons between blood and brain tissue samples in AUD exist.MethodsWe used post-mortem brain tissue samples of 17 deceased patients with AUD and 31 deceased controls to investigate the relationship between blood and brain methylation of the DRD2 promoter.ResultsWhen investigating individual cytosine methylation sites (CpG), several significant differences were found in the nucleus accumbens and hippocampus in the study population. Investigating binding sites with significant differences in methylation levels revealed hypomethylated CpGs targeting mainly activating transcription factors.ConclusionThese findings support an altered transcription of the DRD2 gene in AUD specimens with a consecutively changed reward response in the brain. While methylation between specific brain regions and blood is comparable, our study further suggests that blood methylation cannot provide meaningful perspectives on DRD2 promoter methylation in the brain.