ADH1B, the adipocyte-enriched alcohol dehydrogenase, plays an essential, cell-autonomous role in human adipogenesis.

Alcohol dehydrogenase 1B (ADH1B) is a primate-specific enzyme which, uniquely among the ADH class 1 family, is highly expressed both in adipose tissue and liver. Its expression in adipose tissue is reduced in obesity and increased by insulin stimulation. Interference with ADH1B expression has also been reported to impair adipocyte function. To better understand the role of ADH1B in adipocytes, we used CRISPR/Cas9 to delete ADH1B in human adipose stem cells (ASC). Cells lacking ADH1B failed to differentiate into mature adipocytes manifested by minimal triglyceride accumulation and a marked reduction in expression of established adipocyte markers. As ADH1B is capable of converting retinol to retinoic acid (RA), we conducted rescue experiments. Incubation of ADH1B-deficient preadipocytes with 9-cis-RA, but not with all-transretinol, significantly rescued their ability to accumulate lipids and express markers of adipocyte differentiation. A homozygous missense variant in ADH1B (p.Arg313Cys) was found in a patient with congenital lipodystrophy of unknown cause. This variant significantly impaired the protein's dimerization, enzymatic activity, and its ability to rescue differentiation in ADH1B-deficient ASC. The allele frequency of this variant in the Middle Eastern population suggests that it is unlikely to be a fully penetrant cause of severe lipodystrophy. In conclusion, ADH1B appears to play an unexpected, crucial and cell-autonomous role in human adipocyte differentiation by serving as a necessary source of endogenous retinoic acid.

Alcohol dehydrogenase 1 is a tubular mitophagy-dependent apoptosis inhibitor against septic acute kidney injury.

Alcohol dehydrogenase 1 (ADH1) is an alcohol-oxidizing enzyme with poorlydefined biology. Here we report that ADH1 is highly expressed in kidneys of mice with lethal endotoxemia and is transcriptionally upregulated in tubular cells by lipopolysaccharide (LPS) stimuli through TLR4/NF-κB cascade. The Adh1 knockout (Adh1KO) mice with lethal endotoxemia displayed increased susceptibility to acute kidney injury (AKI) but not systemic inflammatory response. Adh1KO mice develop more severe tubular cell apoptosis in comparison to Adh1 wild-type (Adh1WT) mice during course of lethal endotoxemia. ADH1 deficiency facilitates the LPS-induced tubular cell apoptosis in a caspase-dependent manner. Mechanistically, ADH1 deficiency dampens tubular mitophagy that relies on PINK1-Parkin pathway characterized by the reduced membrane potential, reactive oxygen species (ROS) and release of fragmented mtDNA to cytosol. Kidney-specific overexpression of PINK1 and Parkin by adeno-associated viral vector 9 (AAV9) delivery ameliorates AKI exacerbation in Adh1KO mice with lethal endotoxemia. Our study supports the notion that ADH1 is critical for blockade of tubular apoptosis mediated by mitophagy, allowing the rapid identification and targeting of alcohol-metabolic route applicable to septic AKI.

Mediation analysis unveils a carcinogenic effect of ADH1B rs1229984 through mechanisms other than change in drinking intensity: oesophageal cancer case-control study.

BACKGROUND: Ingested alcohol is predominantly oxidized to acetaldehyde by alcohol dehydrogenase 1B (ADH1B), and acetaldehyde is further oxidized to acetate mainly by aldehyde dehydrogenase 2 (ALDH2). Although alcohol consumption is a convincing risk factor for oesophageal cancer, the role of ADH1B rs1229984 (His48Arg), the single-nucleotide polymorphism associated with slow alcohol metabolism, in oesophageal cancer development is unclear. Because this single-nucleotide polymorphism is associated with both increased risk of oesophageal cancer and drinking intensity, its association with oesophageal cancer might operate either through a direct pathway independently of drinking intensity, via an indirect pathway mediated by drinking intensity, or both. METHODS: To disentangle these different pathways, we applied a mediation analysis to an oesophageal cancer case-control study (600 cases and 865 controls) by defining the ADH1B Arg allele and alcohol consumption as exposure and mediator, respectively, and decomposed the total-effect odds ratio of the ADH1B Arg allele into direct- and indirect-effect odds ratio. RESULTS: The ADH1B Arg allele was associated with oesophageal cancer risk through pathways other than change in drinking intensity (direct-effect odds ratio, 2.03; 95% confidence interval, 1.41-2.92), in addition to the indirect pathway mediated by drinking intensity (indirect-effect odds ratio, 1.27; 95% confidence interval, 1.05-1.53). Further analyses by stratifying genotypes of ALDH2 rs671 (Glu504Lys), the functional single-nucleotide polymorphism that strongly attenuates the enzymatic activity, showed significant direct-effect odds ratio within each stratum. CONCLUSIONS: These results indicate that ADH1B Arg allele contributes to oesophageal cancer risk by slowing alcohol breakdown, in addition to its effect on the amount of alcohol consumed.

Association of alcohol drinking with incident type 2 diabetes and pre-diabetes: The Guangzhou Biobank Cohort Study.

AIMS: We examined associations of baseline alcohol drinking with incident type 2 diabetes (T2D) or impaired fasting glucose (IFG), and explore whether the associations were modified by genetic polymorphisms of aldehyde dehydrogenase-2 (ALDH2) and alcohol dehydrogenase-1B (ADH1B). MATERIALS AND METHODS: All participants were aged 50+ (mean = 60.45; standard deviation = 6.88) years. Information of alcohol consumption was collected at baseline from 2003 to 2008. Incident T2D was defined as fasting glucose ≥7.0 mmol/L or post-load glucose ≥11.1 mmol/L at follow-up examination (2008-2012), self-reported T2D and/or initiation of hypoglycaemia medication or insulin during follow-up. Impaired fasting glucose was defined as fasting glucose ≥5.6 mmol/L and <7 mmol/L. RESULTS: Of 15,716 participants without diabetes and 11,232 participants without diabetes and IFG at baseline, 1624 (10.33%) developed incident T2D and 1004 (8.94%) developed incident IFG during an average 4 years of follow-up. After multivariable adjustments, compared with never drinking, occasional or moderate alcohol drinking was not associated with risk of incident hyperglycaemia (T2D + IFG) (odds ratio (OR) = 1.10, 95% confidence interval (CI) 0.95-1.27, and 0.90 (0.69-1.18), respectively), whereas heavy alcohol drinking was associated with a higher risk of incident hyperglycaemia (T2D + IFG) (OR = 1.82, 95% CI 1.24-2.68). No interactions of sex, overweight/obesity and genetic polymorphisms of ADH1B/ALDH2 genes with alcohol drinking on incident T2D and/or IFG were found (P for interaction from 0.12 to 0.85). CONCLUSIONS: Our results support a detrimental effect of heavy alcohol use on IFG and T2D. No protective effect was found for those carrying lower risk alleles for ADH1B/ALDH2 genes.

Alcohol-induced Hsp90 acetylation is a novel driver of liver sinusoidal endothelial dysfunction and alcohol-related liver disease.

BACKGROUND & AIMS: Liver sinusoidal endothelial cell (LSEC) dysfunction has been reported in alcohol-related liver disease, yet it is not known whether LSECs metabolize alcohol. Thus, we investigated this, as well as the mechanisms of alcohol-induced LSEC dysfunction and a potential therapeutic approach for alcohol-induced liver injury. METHODS: Primary human, rat and mouse LSECs were used. Histone deacetylase 6 (HDAC6) was overexpressed specifically in liver ECs via adeno-associated virus (AAV)-mediated gene delivery to decrease heat shock protein 90 (Hsp90) acetylation in ethanol-fed mice. RESULTS: LSECs expressed CYP2E1 and alcohol dehydrogenase 1 (ADH1) and metabolized alcohol. Ethanol induced CYP2E1 in LSECs, but not ADH1. Alcohol metabolism by CYP2E1 increased Hsp90 acetylation and decreased its interaction with endothelial nitric oxide synthase (eNOS) leading to a decrease in nitric oxide (NO) production. A non-acetylation mutant of Hsp90 increased its interaction with eNOS and NO production, whereas a hyperacetylation mutant decreased NO production. These results indicate that Hsp90 acetylation is responsible for decreases in its interaction with eNOS and eNOS-derived NO production. AAV8-driven HDAC6 overexpression specifically in liver ECs deacetylated Hsp90, restored Hsp90's interaction with eNOS and ameliorated alcohol-induced liver injury in mice. CONCLUSION: Restoring LSEC function is important for ameliorating alcohol-induced liver injury. To this end, blocking acetylation of Hsp90 specifically in LSECs via AAV-mediated gene delivery has the potential to be a new therapeutic strategy. LAY SUMMARY: Alcohol metabolism in liver sinusoidal endothelial cells (LSECs) and the mechanism of alcohol-induced LSEC dysfunction are largely unknown. Herein, we demonstrate that LSECs can metabolize alcohol. We also uncover a mechanism by which alcohol induces LSEC dysfunction and liver injury, and we identify a potential therapeutic strategy to prevent this.

Expression, purification and X-ray crystal diffraction analysis of alcohol dehydrogenase 1 from Artemisia annua L.

Alcohol dehydrogenase 1 identified from Artemisia annua (AaADH1) is a 40 kDa protein that predominately expressed in young leaves and buds, and catalyzes dehydrogenation of artemisinic alcohol to artemisinic aldehyde in artemisinin biosynthetic pathway. In this study, AaADH1 encoding gene was subcloned into vector pET-21a(+) and expressed in Escherichia coli. BL21(DE3), and purified by Co2+ affinity chromatography. Anion exchange chromatography was performed until the protein purity reached more than 90%. Crystallization of AaADH1 was conducted for further investigation of the molecular mechanism of catalysis, and hanging-drop vapour diffusion method was used in experiments. The results showed that the apo AaADH1 crystal diffracted to 2.95 Å resolution, and belongs to space group P1, with unit-cell parameters, a = 77.53 Å, b = 78.49 Å, c = 102.44 Å, α = 71.88°, ß = 74.02°, γ = 59.97°. The crystallization condition consists of 0.1 M Bis-Tris pH 6.0, 13% (w/v) PEG 8000 and 5% (v/v) glycerol.

Associations among liver disease, serum lipid profile, body mass index, ketonuria, meal skipping, and the alcohol dehydrogenase-1B and aldehyde dehydrogenase-2 genotypes in Japanese men with alcohol dependence.

AIM: To elucidate associations among liver disease, lipid profile, body mass index (BMI), ketonuria, and meal skipping under the influence of alcohol dehydrogenase-1B (ADH1B; rs1229984) and aldehyde dehydrogenase-2 (ALDH2; rs671) genotypes in men with alcohol dependence. METHODS: We investigated the associations among these variables in 1768 Japanese men with alcohol dependence. Serum lipid levels were followed up after abstinence. RESULTS: The slow-metabolizing ADH1B Arg/Arg genotype and inactive ALDH2 Glu/Lys genotype increased the age- and drinking-adjusted odds ratio or regression coefficient for fatty liver, ketonuria, and serum high-density-lipoprotein cholesterol levels (HDL-C), and decreased these for cirrhosis and serum triglyceride levels (TG). The ADH1B Arg/Arg genotype increased the adjusted regression coefficient for BMI and non-HDL-C. In addition to the positive interlinkage among fatty liver, BMI, and atherogenic dyslipidemia, positive associations were observed of fatty liver with ketonuria and meal skipping, of cirrhosis with the BMI, and of ketonuria with non-HDL-C. Negative associations were observed of cirrhosis with fatty liver, TG, non-HDL-C, and HDL-C, and of ketonuria with BMI and TG. Overall, after admission for 4 or 6 weeks, the TG and HDL-C decreased, and the serum low-density lipoprotein cholesterol levels increased. However, there was no change of the serum low-density lipoprotein in the patients with cirrhosis or of the serum TG in those with fatty liver. CONCLUSIONS: These associations and the alterations in lipid profile after abstinence serve as useful information for a better understanding of the clinical features of men with alcohol dependence.

Genome-wide analysis reveals alcohol dehydrogenase 1C and secreted phosphoprotein 1 for prognostic biomarkers in lung adenocarcinoma.

To seek out novel promising biomarkers for predicting lung adenocarcinoma (LUAD) prognosis, we conducted this study. First, 279 upregulated and 37 downregulated differentially expressed genes were obtained from LUAD and para-carcinoma tissues by the Affymetrix GeneChip Human Transcriptome Array. Then, we randomly classified samples of LUAD data set GSE31210 as training and testing sets in a 1:1 ratio. Alcohol dehydrogenase 1C (ADH1C) and secreted phosphoprotein 1 (SPP1) were finally identified correlating with the LUAD survival through least absolute shrinkage and selection operator penalized Cox proportion hazards regression model, and applied to build a 2-gene signature related to prognosis in training set. Univariate and multivariable survival analyses suggested that overall survival (OS) and relapse-free survival (RFS) in the 2-gene signature low-risk group were better than the high-risk group. Kaplan-Meier curves proved that elevated ADH1C expression and reduced SPP1 expression were related to better OS and RFS. Besides, the SPP1 expressed higher in LUAD than para-carcinoma tissues using quantitative reverse transcription polymerase chain reaction assay. Finally, the association between the two genes and clinicopathological parameters in 80 LUAD were analyzed, it is suggested that SPP1 was relevant to epidermal growth factor receptor mutation. These findings indicated that ADH1C and SPP1 might be novel promising biomarkers for predicting LUAD prognosis.

Candida Albicans Alcohol Dehydrogenase 1 gene in oral dysplasia and oral squamous cell carcinoma.

This study was designed to examine the prevalence of Candida albicans alcohol dehydrogenase 1 (CaADH1) gene in oral dysplasia as well as oral squamous cell carcinoma (OSCC) with and without lymph node metastasis (LNM) using reverse transcription polymerase chain reaction (RT-PCR) in order to determine its role in initiation, propagation and metastasis of oral dysplasia and carcinoma. Formalin-fixed parafin-embedded specimens were grouped into four groups: 7 control, 16 oral dysplasia, 16 OSCC without LNM and 15 OSCC with LNM. All specimens were examined by periodic acid Schiff (PAS) stain to detect Candida hyphae, while CaADH1 gene was detected using RT-PCR. Candida hyphae were detected by PAS stain in one specimen of oral dysplasia group, 5 OSCC without LNM and 5 OSCC with LNM. CaADH1 gene was detected in 29 specimens (one case of sever dysplasia, 16 OSCC without LNM and 12 OSCC with LNM), with a highly statistically significant between the groups. CaADH1 gene is associated with OSCC with and without metastasis whereas in oral dysplasia it could not be estimated. Further studies with larger sample size are needed to confirm the role of CaADH1 in oral dysplasia and OSCC.

An improved PCR-CTPP assay for the detection of ADH1B Arg48His polymorphism.

BACKGROUND: ADH1B Arg48His polymorphism is associated with the development of alcohol-related diseases. In this study, we aimed to explore an improved polymerase chain reaction with confronting two-pair primers (PCR-CTPP) assay for the detection of ADH1B Arg48His polymorphism. METHODS: A mismatch was introduced at the 3' end of each of the two allele-specific to increase the specificity of the reaction. But beyond that, a new mismatch at-3 positions of outer primers was designed to decrease the efficiency of the aforementioned primers and depresses the amplification of an internal nonspecific DNA control. A total of 180 samples from healthy volunteers Han Chinese were tested to evaluate this new assay. RESULTS: The protocol of PCR-CTPP was successful for genotyping of ADH1B Arg48His. The results from the improved PCR-CTPP assay were confirmed by Sanger sequencing, and correct genotyping rates were 100%.The genotype frequencies were 49.44% (89 cases) for His/His, 46.67% (84 cases) for Arg/His, and 3.89% (seven cases) for Arg/Arg respectively. CONCLUSIONS: This improved PCR-CTPP assay is simple, rapid, cost-effective, and reliable, specific for the detection of ADH1B Arg48His polymorphism in most clinical diagnostic laboratories.

ADH1B: From alcoholism, natural selection, and cancer to the human phenome.

The ADH1B (Alcohol Dehydrogenase 1B (class I), Beta Polypeptide) gene and its best-known functional alleles, Arg48His (rs1229984, ADH1B*2) and Arg370Cys (rs2066702, ADH1B*3), have been investigated in relation to many phenotypic traits; most frequently including alcohol metabolism and alcohol drinking behaviors, but also human evolution, liver function, cancer, and, recently, the comprehensive human phenome. To understand ADH1B functions and consequences, we provide here a bioinformatic analysis of its gene regulation and molecular functions, literature review of studies focused on this gene, and a discussion regarding future research perspectives. Certain ADH1B alleles have large effects on alcohol metabolism, and this relationship particularly encourages further investigations in relation to alcoholism and alcohol-associated cancer to understand better the mechanisms by which alcohol metabolism contributes to alcohol abuse and carcinogenesis. We also observed that ADH1B has complex mechanisms that regulate its expression across multiple human tissues, and these may be involved in cardiac and metabolic traits. Evolutionary data strongly suggest that the selection signatures at the ADH1B locus are primarily related to effects other than those on alcohol metabolism. This is also supported by the involvement of ADH1B in multiple molecular pathways and by the findings of our recent phenome-wide association study. Accordingly, future studies should also investigate other functions of ADH1B potentially relevant for the human phenome. © 2017 Wiley Periodicals, Inc.

Platelet Counts and Genetic Polymorphisms of Alcohol Dehydrogenase-1B and Aldehyde Dehydrogenase-2 in Japanese Alcoholic Men.

BACKGROUND: Thrombocytopenia during intoxication, rebound thrombocytosis during 1 to 3 weeks of abstinence, and subsequent normalization of the platelet count are common in alcoholics. METHODS: We evaluated 989 Japanese alcoholic men to identify the effects of genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B; rs1229984) and aldehyde dehydrogenase-2 (ALDH2; rs671) on platelet counts during an 8-week in-hospital abstinence period. RESULTS: Thrombocytopenia (<15 × 104 /µl) was observed in 25.9% of the subjects upon admission. The platelet counts increased from 21.4 ± 0.3 × 104 /µl (mean ± SE) to 27.6 ± 0.3 × 104 /µl, and a rebound platelet increase of  ≥10 × 104 /µl was observed in 28.6% of the patients during the first 2 weeks after admission. By 4 weeks, the mean platelet counts had returned to intermediate levels and remained stable thereafter. The reversible suppression and rebound increase in the platelet counts were more prominent in the slow-metabolizing ADH1B*1/*1 group than in the fast-metabolizing ADH1B*2 group. Throughout the 8 weeks, the mean platelet counts of the active ALDH2*1/*1 group were consistently lower than those in the inactive ALDH2*1/*2 group. Cirrhosis was a strong determinant of a lower platelet count. After adjustments for nongenetic factors including cirrhosis, multiple linear regression analyses showed that the ADH1B*1/*1 genotype was associated with a lower platelet count (partial regression coefficient = -1.3 × 104 /µl) on the admission day, but subsequently had a positive effect on the platelet count at 1 and 2 weeks after admission (+1.5 and +3.8 × 104 /µl, respectively). The ALDH2*1/*1 genotype was associated with a lower platelet count (-2.1 to -3.9 × 104 /µl) consistently throughout the 8 weeks. Multiple logistic regression analyses showed that the ADH1B*1/*1 genotype increased the risk of thrombocytopenia upon admission (odds ratio [95% confidence interval] = 1.61 [1.14 to 2.27]) and of a rebound platelet increase during the first 2 weeks (3.86 [2.79 to 5.34]). The ALDH2*1/*1 genotype increased the risk of thrombocytopenia upon admission (1.73 [1.06 to 2.82]). CONCLUSIONS: In alcoholics, the ADH1B*1/*1 genotype increased the risk of thrombocytopenia upon admission and of a rebound platelet increase 2 weeks thereafter, while the ALDH2*1/*1 genotype was associated with lower platelet counts throughout the 8-week hospital stay.

Recovery from anemia and leukocytopenia after abstinence in Japanese alcoholic men and their genetic polymorphisms of alcohol dehydrogenase-1B and aldehyde dehydrogenase-2.

BACKGROUND: The combination of the fast-metabolizing alcohol dehydrogenase-1B (ADH1B*2 allele) and inactive heterozygous aldehyde dehydrogenase-2 (ALDH2*1/*2) increases susceptibility to macrocytic anemia and leukocytopenia in alcoholics due to severe acetaldehydemia. More than half of Japanese drinkers with esophageal cancer have this genotype combination. METHODS: To assess the recovery of hematologic abnormalities after drinking cessation, changes in blood erythrocyte indices and leukocyte count during 8-week hospital stay were evaluated in 925 Japanese alcoholic men. We used four categories in ascending order for high blood acetaldehyde exposure from drinking: A, ADH1B*1/*1 plus ALDH2*1/*1; B, ADH1B*2 plus ALDH2*1/*1; C, ADH1B*1/*1 plus ALDH2*1/*2; and D, ADH1B*2 plus ALDH2*1/*2. RESULTS: Mean values of hemoglobin and hematocrit were the lowest, and those of mean corpuscular volume (MCV) were markedly the highest in the D group on admission, and returning toward normal after abstinence, but the inter-group differences remained significant throughout the 8 weeks. The mean leukocyte count was the lowest in the D group on admission, but increased during 4-week abstinence when the inter-group differences were no longer significant. Frequencies of MCV ≥110 fl (50.5%), hemoglobin levels <11.5 g/dL (32.7%), hemoglobin levels <10.0 g/dL (9.9%) and leukocytopenia <4000/µL (22.8%) were the highest in the D group on the admission day and decreased at the 4-week abstinence (28.7%, 18.8%, 4.0% and 7.9%, respectively). The inter-group differences in frequencies of the severe anemia and leukocytopenia disappeared after 4-week abstinence. CONCLUSIONS: Drinking cessation before surgery and/or chemoradiation treatment for esophageal cancer may be effective for recovery from anemia and leukocytopenia in drinkers belonging to the D group.

Effect of alcohol dehydrogenase 1C (ADH1C) genotype on vitamin A restriction and marbling in Korean native steers.

OBJECTIVE: This work was to find the correlation of alcohol dehydrogenase 1C (ADH1C) genotype with vitamin A reduction and carcass traits during the vitamin A restriction period. METHODS: In study 1, 60 Korean native steers were fed a diet (890 IU/kg) with 8,000 IU and 0 IU of supplemental premix vitamin A/kg of dry matter (DM) for control and treatment group, respectively. The levels of serum vitamin A were analyzed through high preparative performance liquid chromatography, and the ADH1C genotype was analyzed based on polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP; 78.1% TT type, 21.9% TC type); however, CC type was not found. Then, the interaction between ADH1C and carcass traits on the vitamin A restriction was investigated in study 2. A total of 136 Korean native steers were fed a diet that included 930 IU/kg vitamin A of DM. RESULTS: Serum vitamin A in treatment was reduced to 112.4 IU/dL in steers with TT type of ADH1C, while for steers with TC type the concentration of serum vitamin A was dropped to 79.5 IU/dL (p<0.1) in study 1. This showed that TC type had the potential to lower serum vitamin A concentration during vitamin A restriction compared to TT type. In study 2 we found that eye muscle area, marbling and carcass weight in Korean native steers with TC type were higher than in steers with TT type (p<0.05). CONCLUSION: The interaction between vitamin A restriction and TC type of ADH1C gene could have the potential of increasing the marbling in Korean native steers. These results indicated that steers with TC type of the ADH1C gene were more sensitive to the change of serum vitamin A than TT types. Furthermore, this finding has the potential to enable a higher marbling score under the condition of vitamin A restriction in Korean native steers.

Which alcohol use disorder criteria contribute to the association of ADH1B with alcohol dependence?

Although alcohol dependence (AD) is approximately 50% heritable, little is known about how specific genetic loci affect AD risk. In a genome-wide association study (GWAS), we identified highly significant associations between two population-specific functional variants in the alcohol dehydrogenase 1B gene (ADH1B) and AD in African-Americans (AAs; rs2066702) and European-Americans (EAs; rs1229984). In the current study, we determined which specific diagnostic criteria contributed to the observed associations of ADH1B SNPs with AD. Our analysis included both the DSM-IV and DSM-5 diagnostic systems. We also investigated the relationship of ADH1B variants to the maximum number of drinks consumed in a 24-hour period (MaxDrinks), a presumed intermediate phenotype of AD. We found that, although all criteria made strong individual contributions to the associations, the largest contributions came from those reflecting neuroadaptation: tolerance (rs2066702) and withdrawal (rs1229984). Overall, evidence for association with DSM-5 criteria was slightly stronger than for DSM-IV criteria. For rs2066702, results were similar for DSM-IV and DSM-5 criteria. However, the most significant DSM-5 criterion associated with rs1229984 was alcohol-related social/interpersonal problems. Both ADH1B variants were associated with MaxDrinks, a measure of innate tolerance, and MaxDrinks mediated the associations between ADH1B and alcohol outcomes. We replicated the findings for rs2066702 and tolerance in an independent sample of AAs. Taken together, these results suggest that variation in ADH1B affects the adaptation to heavy drinking, highlighting population-specific differences in genetic risk for AUD. They also suggest that the revisions reflected in DSM-5 AUD may enhance the utility of that diagnosis for gene finding.

Association between alcohol dehydrogenase-2 gene polymorphism and esophageal cancer risk: a meta-analysis.

BACKGROUND: It has been shown that gene polymorphisms may play an important role in the carcinogenesis of esophageal cancer. This study is to investigate the role of alcohol dehydrogenase 1B (ADH1B) gene Arg47His polymorphism in esophageal cancer susceptibility. METHODS: Case-control studies published between January 2000 and June 2015 were searched to retrieve relevant articles. The pooled odds ratio (OR) and 95 % confidence interval (CI) were employed to calculate the strength of association. RESULTS: A total of 23 relevant articles were finally selected for the analysis, including 9338 esophageal cancer patients and 14,896 matched controls. Overall, we found that the 47His allele was significant associated with the decreased risk of esophageal cancer when compared with the 47Arg allele in total populations (A vs. G: OR = 0.67, 95 % CI = 0.59-0.76, P < 0.00001). This protective relationship was observed under other genetic models as well (P < 0.00001). Subgroup analysis by ethnicity showed that ADH1B Arg47His variant was associated with the decreased esophageal cancer risk under all the genetic models (P < 0.00001) among Asians, especially in Chinese and Japanese; while in non-Asians, no significant correlation was detected in any genetic models (P > 0.05). Furthermore, Arg/Arg genotype of ADH1B Arg47His variant combined with drinking, smoking and males appeared to show a high risk in patients with esophageal cancer. CONCLUSIONS: Our results suggested that ADH1B gene Arg47His variant was associated with the decreased esophageal cancer risk. Genetic-environmental interaction should be further considered in the future researches.

Relationships of alcohol dehydrogenase 1B (ADH1B) and aldehyde dehydrogenase 2 (ALDH2) genotypes with alcohol sensitivity, drinking behavior and problem drinking in Japanese older men.

OBJECTIVES: Many East Asians have the genetic polymorphisms rs1229984 in alcohol dehydrogenase 1B (ADH1B) and rs671 in aldehyde dehydrogenase 2 (ALDH2). Here we analyzed the relationships of the two genotypes with alcohol sensitivity, drinking behavior and problem drinking among older and younger men living in rural areas of Japan. METHODS: The subjects were 718 Japanese men aged 63.3 ± 10.8 (mean ± SD), categorized into the older (≥65 years, n = 357) and younger (<65 years, n = 361) groups. Facial flushing frequency, drinking behavior and positive CAGE results were compared among the genotypes using Bonferroni-corrected χ(2) test and a multivariate logistic regression analysis adjusting for age, BMI and lifestyle factors. RESULTS: The frequency of 'always' facial flushing among the ADH1B*1/*2 carriers was significantly lower than that among the ADH1B*2/*2 carriers in the older group (P < 0.01). The alcohol consumption (unit/day) in the ADH1B*1/*2 carriers tended to be higher compared with that in the ADH1B*2/*2 carriers among the older group (P = 0.050). In the younger group, no significant differences in alcohol sensitivity and drinking habits were generally found among the ADH1B genotypes. The ADH1B*1/*1 genotype tended to be positively associated with problem drinking in the older group (P = 0.080) but not in the younger group. The ALDH2 genotypes consistently and strongly affected the alcohol sensitivity, drinking behavior and problem drinking in both the younger and older group. CONCLUSIONS: We for the first time observed a significant difference in alcohol sensitivity between ADH1B*1/*2 and ADH1B*2/*2 in older men aged 65 and above.

Aldehyde dehydrogenase 2 polymorphism for development to hepatocellular carcinoma in East Asian alcoholic liver cirrhosis.

BACKGROUND AND AIM: We aimed to clarify the influences of aldehyde dehydrogenase 2 (ALDH2), alcohol dehydrogenase 1B (ADH1B) polymorphisms, and ethanol consumption profile to hepatocellular carcinoma (HCC) development in alcoholic liver cirrhosis without chronic hepatitis B and C virus infection (non-B non-C). METHODS: Of 236 freshly diagnosed non-B non-C alcoholic liver cirrhosis patients, 67 were diagnosed as HCC and the remaining 169 as not having HCC. The relationship between the genetic polymorphisms and development to HCC were evaluated in well-matched patients with HCC (HCC group, n = 67) and without HCC (non-HCC group, n = 67) using propensity scores in age, sex, and prevalence of diabetes mellitus. RESULTS: Daily amount of ethanol consumption was significantly lower (P = 0.005), and consumptive period was significantly longer (P = 0.003) in HCC group than non-HCC group. Of 134 well-matched patients, 113 (84.3%) had ALDH2*1/*1 genotype and 21 (15.7%) had ALDH2*1/*2 genotype. In HCC development, consumptive long period (P = 0.007) and carrying ALDH2*1/*2 genotype (P = 0.026) were identified as significant factors independently participated, while there was no relation to ADH1B polymorphism. In addition, consumptive period was significantly longer in HCC group than non-HCC group in ALDH2*1/*1 genotype patients (P = 0.0005), while there was no difference in profile of ethanol consumption in ALDH2*1/*2 genotype patients. Among HCC group, daily (P = 3.78 × 10(-6) ) and cumulative amount (P = 4.89 × 10(-6) ) of ethanol consumption were significantly higher in ALDH2*1/*1 genotype patients than ALDH2*1/*2 genotype patients. CONCLUSION: In alcoholic liver cirrhosis, investigations of ALDH2 polymorphism and ethanol consumption profile are useful for prediction of HCC development.

Roles of the ALDH2 and ADH1B genotypes on the association between alcohol intake and serum adiponectin levels among Japanese male workers.

BACKGROUND: Adiponectin secreted from adipose tissue is assumed to mediate protective effects on development of metabolic syndrome (MetS) and MetS-related diseases such as cardiovascular diseases and cancer. Relationship between alcohol intake and circulating adiponectin levels is not consistent among the several previous studies. In the present study, we investigated effects of alcohol intake and the alcohol-related polymorphisms on serum adiponectin levels among Japanese male workers. METHODS: We conducted a cross-sectional design study with 541 male workers aged 51.5 ± 5.9 (mean ± SD) years in a Japanese plant. Information on alcohol intake and other lifestyles was obtained by a self-administered questionnaire. Serum total adiponectin (T-Ad), high-molecular-weight adiponectin (HMW-Ad), medium-molecular-weight adiponectin (MMW-Ad), and low-molecular-weight adiponectin (LMW-Ad) levels were measured by the enzyme-linked immune assay system kit. Two genotypes in the alcohol dehydrogenase-1B (ADH1B) and aldehyde dehydrogenase-2 (ALDH2) genes were determined using blood sample. In multivariate regression analyses, we adjusted for age, body mass index, smoking, and physical exercise. RESULTS: Among all subjects, high alcohol consumption of 12 units (1 unit contains 22.9 g of ethanol) a week or more was negatively associated with T-Ad levels in the multivariate model, although not significant. When we performed analyses separately for each genotype, high alcohol consumption was negatively associated with T-Ad, HMW-Ad, and LMW-Ad levels only in those with ADH1B *2/*2. Such relationships were not observed in each ALDH2 genotype group. CONCLUSIONS: High alcohol consumption was inversely associated with T-Ad, HMW-Ad, and LMW-Ad levels in those with ADH1B *2/*2 genotype, but not in those with the other ADH1B genotypes. To our knowledge, this is the first study that reports combined effects of the alcohol-related polymorphisms and alcohol intake on serum adiponectin levels. Additional studies are required to confirm the present finding.

Alcohol-metabolizing genes and alcohol phenotypes in an Israeli household sample.

BACKGROUND: Alcohol dehydrogenase 1B and 1C (ADH1B and ADH1C) variants have been robustly associated with alcohol phenotypes in East Asian populations, but less so in non-Asian populations where prevalence of the most protective ADH1B allele is low (generally <5%). Further, the joint effects of ADH1B and ADH1C on alcohol phenotypes have been unclear. Therefore, we tested the independent and joint effects of ADH1B and ADH1C on alcohol phenotypes in an Israeli sample, with higher prevalence of the most protective ADH1B allele than other non-Asian populations. METHODS: A structured interview assessed lifetime drinking and alcohol use disorders (AUDs) in adult Israeli household residents. Four single nucleotide polymorphisms (SNPs) were genotyped: ADH1B (rs1229984, rs1229982, and rs1159918) and ADH1C (rs698). Regression analysis examined the association between alcohol phenotypes and each SNP (absence vs. presence of the protective allele) as well as rs698/rs1229984 diplotypes (also indicating absence or presence of protective alleles) in lifetime drinkers (n = 1,129). RESULTS: Lack of the ADH1B rs1229984 protective allele was significantly associated with consumption- and AUD-related phenotypes (OR = 1.77 for AUD; OR = 1.83 for risk drinking), while lack of the ADH1C rs698 protective allele was significantly associated with AUD-related phenotypes (OR = 2.32 for AUD). Diplotype analysis indicated that jointly ADH1B and ADH1C significantly influenced AUD-related phenotypes. For example, among those without protective alleles for ADH1B or ADH1C, OR for AUD was 1.87 as compared to those without the protective allele for ADH1B only and was 3.16 as compared to those with protective alleles for both ADH1B and ADH1C. CONCLUSIONS: This study adds support for the relationship of ADH1B and ADH1C and alcohol phenotypes in non-Asians. Further, these findings help clarify the mixed results from previous studies by showing that ADH1B and ADH1C jointly effect AUDs, but not consumption. Studies of the association between alcohol phenotypes and either ADH1B or ADH1C alone may employ an oversimplified model, masking relevant information.