Homocysteine and alcoholism

The Status of Oxidative Stress in Patients with Alcohol Dependence: A Meta-Analysis

Alcohol-induced oxidative stress (OS) plays a pivotal role in the pathophysiology of alcohol dependence (AD). This meta-analysis was aimed at investigating the changes in the levels of OS biomarkers in AD patients. We included relevant literature published before 1 April 2022, from the PubMed, Web of Science, and EBSCO databases following PRISMA guidelines. Finally, 15 eligible articles were enrolled in this meta-analysis, including 860 patients and 849 controls. Compared with healthy controls, AD patients had lower activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes, and lower levels of albumin, while levels of malondialdehyde (MDA), vitamin B12, homocysteine, and bilirubin were significantly increased in serum/plasma samples of AD subjects (all p < 0.05). In male patients, the activities of SOD and GPx were increased in serum/plasma but decreased in erythrocytes (all p < 0.05). The opposite trends in the level of SOD and GPx activities in serum/plasma and erythrocytes of male patients could be used as the biomarker of alcohol-induced OS injury, and the synergistic changes of MDA, vitamin B12, albumin, bilirubin, and homocysteine levels should also be considered.

Exercise Mitigates Alcohol Induced Endoplasmic Reticulum Stress Mediated Cognitive Impairment through ATF6-Herp Signaling

Chronic ethanol/alcohol (AL) dosing causes an elevation in homocysteine (Hcy) levels, which leads to the condition known as Hyperhomocysteinemia (HHcy). HHcy enhances oxidative stress and blood-brain-barrier (BBB) disruption through modulation of endoplasmic reticulum (ER) stress; in part by epigenetic alternation, leading to cognitive impairment. Clinicians have recommended exercise as a therapy; however, its protective effect on cognitive functions has not been fully explored. The present study was designed to observe the protective effects of exercise (EX) against alcohol-induced epigenetic and molecular alterations leading to cerebrovascular dysfunction. Wild-type mice were subjected to AL administration (1.5 g/kg-bw) and subsequent treadmill EX for 12 weeks (5 day/week@7-11 m/min). AL affected mouse brain through increases in oxidative and ER stress markers, SAHH and DNMTs alternation, while decreases in CBS, CSE, MTHFR, tight-junction proteins and cellular H2S levels. Mechanistic study revealed that AL increased epigenetic DNA hypomethylation of Herp promoter. BBB dysfunction and cognitive impairment were observed in the AL treated mice. AL mediated transcriptional changes were abolished by administration of ER stress inhibitor DTT. In conclusion, exercise restored Hcy and H2S to basal levels while ameliorating AL-induced ER stress, diminishing BBB dysfunction and improving cognitive function via ATF6-Herp-signaling. EX showed its protective efficacy against AL-induced neurotoxicity.

Blood homocysteine concentration and mood disorders with mixed features among patients with alcohol use disorder

BACKGROUND

Blood homocysteine concentration (BHC) is higher in patients with alcohol use disorder (AUD). Previous studies have found a relationship between depressive symptoms severity and BHC in AUD patients and recently some authors have found high BHC among patients with bipolar disorder, both during manic and depressive episodes and in euthymic state. However, BHC in patients with mixed mood episode has not yet been investigated. The aim of this study was to evaluate the BHC of patients with AUD and mixed mood episode.

METHODS

A sample of AUD outpatients was assessed by Mini-International Neuropsychiatric Interview (MINI Plus): those with a DSM-IV-TR mood disorder with mixed features were included in the MIXED group (n = 45), whereas those without mood episode were gathered in the NO MOOD group (n = 23). Two subgroups, MIXMANIA and MIXDEPRESSION, were formed according to the prevalence of manic or depressive symptoms, assessed by Young Mania Rating Scale (YMRS), and Hamilton Rating Scale for Depression (HDRS). The Alcohol Use Disorder Identification Test (AUDIT) was used to appraise the AUD. BHC was determined by High-Performance Liquid Chromatography.

RESULTS

The MIXED group showed greater severity of both depressive (26.35 ± 9.96 vs. 4.77 ± 0.92; p < 0.001) and manic (22.35 ± 3.30 vs. 6.14 ± 1.12; p < 0.001) symptoms, and higher BHC (28.80 ± 11.47 vs. 10.83 ± 2.81; p < 0.001), than the NO MOOD group. BHC was strongly correlated to the HDRS, YMRS and AUDIT scores, just as HDRS was to YMRS, and AUDIT was to both HDRS and YMRS, in the MIXED group only (p < 0.001). The MIXDEPRESSION subgroup showed higher BHC than the MIXMANIA subgroup (Mdn = 42.96, IQR = 10.44 vs. Mdn = 19.77, IQR = 5.93; p < 0.001). A linear regression model conducted on the MIXED group found a significant predictive value for BHC of both HDRS (β = 0.560, t = 2.43, p = 0.026) and AUDIT (β = 0.348, t = 2.17, p = 0.044).

CONCLUSIONS

Depressive symptoms seem to be mainly implicated in the BHC elevation among patients with both mixed features mood disorder and AUD.

Validation of differential GDAP1 DNA methylation in alcohol dependence and its potential function as a biomarker for disease severity and therapy outcome

Alcohol dependence is a severe disorder contributing substantially to the global burden of disease. Despite the detrimental consequences of chronic alcohol abuse and dependence, effective prevention strategies as well as treatment options are largely missing to date. Accumulating evidence suggests that gene-environment interactions, including epigenetic mechanisms, play a role in the etiology of alcohol dependence. A recent epigenome-wide study reported widespread alterations of DNA methylation patterns in alcohol dependent patients compared to control individuals. In the present study, we validate and replicate one of the top findings from this previous investigation in an independent cohort: the hypomethylation of GDAP1 in patients. To our knowledge, this is the first independent replication of an epigenome-wide finding in alcohol dependence. Furthermore, the AUDIT as well as the GSI score were negatively associated with GDAP1 methylation and we found a trend toward a negative association between GDAP1 methylation and the years of alcohol dependency, pointing toward a potential role of GDAP1 hypomethylation as biomarker for disease severity. In addition, we show that the hypomethylation of GDAP1 in patients reverses during a short-term alcohol treatment program, suggesting that GDAP1 DNA methylation could also serve as a potential biomarker for treatment outcome. Our data add to the growing body of knowledge on epigenetic effects in alcohol dependence and support GDAP1 as a novel candidate gene implicated in this disorder. As the role of GDAP1 in alcohol dependence is unknown, this novel candidate gene should be followed up in future studies.

Use of Carnosine for Oxidative Stress Reduction in Different Pathologies

The main properties and biological effects of the antioxidant carnosine, the natural dipeptide β-alanyl-L-histidine, are considered. Data on the effective use of carnosine in different pathologies are presented. Special attention is paid to issues of use of carnosine in neurologic and mental diseases, in alcoholism as well as in physiological states accompanied by activation of free-radical processes and formation of oxidative stress.

Homocysteine, cortisol, diabetes mellitus, and psychopathology

OBJECTIVE

This study investigates the association of homocysteine and cortisol with psychological factors in type 2 diabetic patients.

METHOD

Homocysteine, cortisol, and psychological variables were analyzed from 131 diabetic patients. Psychological factors were assessed with the Eysenck Personality Questionnaire (EPQ), Hostility and Direction of Hostility Questionnaire (HDHQ), the Symptom Checklist 90-R (SCL 90-R), the Zung Self-Rating Depression Scale (ZDRS), and the Maudsley O-C Inventory Questionnaire (MOCI). Blood samples were taken by measuring homocysteine and cortisol in both subgroups during the initial phase of the study (T0). One year later (T1), the uncontrolled diabetic patients were reevaluated with the use of the same psychometric instruments and with an identical blood analysis.

RESULTS

The relation of psychoticism and homocysteine is positive among controlled diabetic patients (P value = 0.006 < 0.05) and negative among uncontrolled ones (P value = 0.137). Higher values of cortisol correspond to lower scores on extraversion subscale (r(p) = -0.223, P value = 0.010). Controlled diabetic patients showed a statistically significant negative relationship between homocysteine and the act-out hostility subscale (r(sp) = -0.247, P = 0.023). There is a statistically significant relationship between homocysteine and somatization (r(sp) = -0.220, P = 0.043).

CONCLUSIONS

These findings support the notion that homocysteine and cortisol are related to trait and state psychological factors in patients with diabetes mellitus type 2.

Differential sensitivity of prefrontal cortex and hippocampus to alcohol-induced toxicity

The prefrontal cortex (PFC) is a brain region responsible for executive functions including working memory, impulse control and decision making. The loss of these functions may ultimately lead to addiction. Using histological analysis combined with stereological technique, we demonstrated that the PFC is more vulnerable to chronic alcohol-induced oxidative stress and neuronal cell death than the hippocampus. This increased vulnerability is evidenced by elevated oxidative stress-induced DNA damage and enhanced expression of apoptotic markers in PFC neurons. We also found that one-carbon metabolism (OCM) impairment plays a significant role in alcohol toxicity to the PFC seen from the difference in the effects of acute and chronic alcohol exposure on DNA repair and from exaggeration of the damaging effects upon additional OCM impairment in mice deficient in a key OCM enzyme, methylenetetrahydrofolate reductase (MTHFR). Given that damage to the PFC leads to loss of executive function and addiction, our study may shed light on the mechanism of alcohol addiction.

A Study on MTHFR C677T Gene Polymorphism and Alcohol Dependence among Meiteis of Manipur, India

Chronic alcohol consumption is reported to be associated with increase in plasma homocysteine levels which is further influenced by the polymorphism in methylenetetrahydrofolate reductase (MTHFR) gene. The present study aims to understand the extent of the MTHFR C677T polymorphism in alcohol dependent (AD) cases of Meiteis of Manipur, a Mendelian population of India. MTHFR C677T polymorphism was screened in 313 controls and 139 alcohol dependent (AD) cases who all met DSM-IV criteria for alcohol dependence. Both AD cases and controls were unrelated up to 1st cousin. Among the control group, different drinking patterns like abstainer/nondrinkers (NDs), occasional drinkers (ODs), and moderate drinkers (MDs) are included. Both the groups were found to be in Hardy-Weinberg equilibrium (P > 0.05). Genotypic and allelic frequency distribution of MTHFR C677T polymorphism did not differ significantly between AD cases and controls (P > 0.05). However, individuals carrying mutant (T) allele show more than 1-fold increased risk for AD though not significant (OR = 1.43; 95% CI 0.41–5.01, P > 0.05). In conclusion, MTHFR C677T polymorphism is not found to be risk marker for AD in present studied population. However, higher prevalence of the mutant T allele may exacerbate deleterious health risk in future especially among alcohol drinkers.

Genetics and epigenetics of alcohol dependence

Alcohol dependence is a severe and common disorder associated with high morbidity and mortality rates. Genetic as well as environmental factors are known to modulate susceptibility to alcohol dependence. There is a growing body of evidence suggesting that this interaction between the genome and the environment is mediated by epigenetic mechanisms, e.g. DNA methylation at CpG sites. Following an introduction of epigenetic regulation of gene transcription, this review will provide an overview over recent genetic and epigenetic findings in the context of alcohol dependence focusing on human studies. Finally, we will discuss the current limitations of epigenetic studies as well as the implications of genetic and epigenetic findings for the development of better treatment and prevention strategies.

Are plasma homocysteine and methionine elevated when binging and purging behavior complicates anorexia nervosa? Evidence against the transdiagnostic theory of eating disorders

OBJECTIVE

To determine whether plasma total homocysteine (tHcy) and plasma methionine levels are different in anorexia nervosa restricting type (AN-R) compared to anorexia nervosa binge eating/purging type (AN-BP).

METHODS

Cross-sectional design.

SUBJECTS

Subjects were recruited from the outpatient program of the Eating Disorders Program at St. Paul's Hospital, Vancouver, Canada. All subjects had a current Diagnostic and Statistical Manual of mental Disorders - Fourth Edition (DSM-IV) AN-R, or AN-BP diagnosis. Controls were recruited from staff and trainees of Child and Family Research Institute, and Children's and Women's Hospital, University of British Columbia.

RESULTS

Samples were obtained from AN-R (N=30), AN-BP (N=32) and control women (N=73) and men (N=33). The 5- 95th% confidence intervals from the control women were taken as the normal range. The plasma tHcy and methionine for the control group had a 5-95th percentile range of 5.66-10.57 and 15.3-40.2 microM, respectively. Plasma tHcy was elevated in women with AN-BP (9.24+/-0.85 microM, N=32) but not with AN-R (7.90+/-0.38 microM, N=30). Plasma methionine was decreased in women with AN-BP (22.2+/-1.43 microM, N=32) compared to the control group of women (25.1+/-0.89 microM). The plasma methionine/tHcy ratio was elevated in the women with AN-BP (0.50+/-0.09) but not in those with AN-R (0.34+/-0.03).

CONCLUSION

Elevated plasma tHcy and decreased plasma methionine are consistent with impaired homocysteine remethylation. Altered methyl transfer capacity or methyl deficiency could impair monoamine neurotransmitter metabolism potentially impacting cognitive and psychological function.We hypothesize that the treatment of AN-BP should consider the need for nutritional support of methyl metabolism.

Association of hyperhomocysteinemia to alcohol withdrawal in chronic alcoholics

This study is conducted in chronic alcoholics to assess the association of an Individual's level of serum homocysteine with the success of achieving alcohol deaddiction in the patient. The patients' nutrition status is also assessed. 50 chronic alcoholics admitted to a deaddiction center were inducted into the study. Patients underwent an 8 weeks holistic program to promote rehabilitation from alcoholism. All the patients were addicted to alcohol for 8 - 10 years. Of the 50 patients enrolled, 39 of them completed the 8 weeks program including complete abstinence from alcohol during this period. Fasting blood samples were collected on admission and again after 8 weeks of alcohol abstinence for analyses of serum homocysteine and serum prealbumin, transferrin, total proteins and albumin, gammaglutamyl transferase (GGT) and alanine transaminase (ALT). Of the 50 patients enrolled in the study, 39 completed the 8 weeks rehabilitation program. 11 patients discontinued within 2 weeks of admission. During the 8 weeks of complete alcohol abstinence, patients were given a balanced diet and multivitamin supplements. A significant improvement in their nutritional status was noted by the elevation of serum levels of prealbumin, transferrin, total proteins and albumin. Serum homocysteine levels decreased significantly (p<0.002) to normal levels from previous hyperhomocytenemia. This was accompanied by decrease in serum GGT and ALT levels indicating improved liver functions. Serum estimation of homocysteine in chronic alcoholics is important to assess whether the patient will have a successful rehabilitation. Normal homocysteine levels are achieved after dietary changes and abstinence from alcohol. Timely correction of hyperhomocysteinemia also provides successful rehabilitation.

Alcohol related changes in regulation of NMDA receptor functions

Long-term alcohol exposure may lead to development of alcohol dependence in consequence of altered neurotransmitter functions. Accumulating evidence suggests that the N-methyl-D-aspartate (NMDA) type of glutamate receptors is a particularly important site of ethanol's action. Several studies showed that ethanol potently inhibits NMDA receptors (NMDARs) and prolonged ethanol exposition leads to a compensatory "up-regulation" of NMDAR mediated functions. Therefore, alterations in NMDAR function are supposed to contribute to the development of ethanol tolerance, dependence as well as to the acute and late signs of ethanol withdrawal.A number of publications report alterations in the expression and phosphorylation states of NMDAR subunits, in their interaction with scaffolding proteins or other receptors in consequence of chronic ethanol treatment. Our knowledge on the regulatory processes, which modulate NMDAR functions including factors altering transcription, protein expression and post-translational modifications of NMDAR subunits, as well as those influencing their interactions with different regulatory proteins or other downstream signaling elements are incessantly increasing. The aim of this review is to summarize the complex chain of events supposedly playing a role in the up-regulation of NMDAR functions in consequence of chronic ethanol exposure.