Aldehyde dehydrogenase 2 (ALDH2), as one of the most important alcohol metabolizing enzymes, plays a significant role in the detoxification process of acetaldehyde which is a main carcinogenic product of alcoholic metabolism. Alteration in its genotypes (particularly at the site of rs671) is closely associated with a variety of tumors in drinkers. Recent advance in the research of the association of the ALDH2 gene rs671 polymorphisms with cancer susceptibility in drinkers is reviewed.
Alcohol Drinking ; genetics ; Aldehyde Dehydrogenase ; genetics ; Aldehyde Dehydrogenase, Mitochondrial ; Genetic Predisposition to Disease ; Humans ; Neoplasms ; etiology ; genetics ; Polymorphism, Genetic

OBJECTIVE: To explore alcohol pharmacokinetics as well as acetaldehyde level in peripheral blood in human subjects with different ALDH2 genotypes after drinking. METHODS: Venous blood samples of 14 unrelated volunteers were collected. Polymerase chain reaction-restriction fragment length polymorphism technology was adopted for DNA extraction and ALDH2 genotyping. The volunteers were asked to drink beer at certain doses. The concentration of alcohol and acetaldehyde were assayed by headspace gas chromatography method at different time. The pharmacokinetic parameters were calculated. RESULTS: According to the results of electrophoresis, 5 people carried ALDH2*1/*1 as wild group and 9 people carried ALDH2*1/*2 as mutation group. The good linear range of alcohol and acetaldehyde were 0-1 570.7 microg/mL and 0-5.1772 microg/mL, respectively. The AUC values of alcohol and acetaldehyde and the t1/2Z value of alcohol were higher in the mutation group than that in the wild group. But the CL/F value of alcohol was lower in the mutation group than that in the wild group (P<0.05). CONCLUSION After the consumption of alcohol, alcohol and acetaldehyde metabolism in blood slow down in ALDH2*1/*2 mutation group influenced by the inhibition of enzyme activity, leading to the accumulation of acetaldehyde in peripheral blood, thus reinforcing their effects in the body.
Alcohol Drinking ; Aldehyde Dehydrogenase/genetics* ; Aldehyde Dehydrogenase, Mitochondrial ; Ethanol/metabolism* ; Genotype ; Humans ; Polymerase Chain Reaction ; Polymorphism, Genetic

Objective To explore the change rules of blood ethanol and blood acetaldehyde concentration, the impairment of psychomotor functions of different acetaldehyde dehydrogenase （ALDH） 2 genotype individuals after alcohol consumption and the relationship among them. Methods The ALDH2 genotypes in seventy-nine healthy volunteers were obtained by SNaPshot^TM method, then divided into ALDH2*1/*1 （wild type） and ALDH2*1/*2 （mutant type） group. After volunteers consumed 1.0 g/kg of alcohol, blood ethanol concentration and blood acetaldehyde concentration at a series of time points before and after alcohol consumption and psychomotor functions, such as, visual selective response time, auditory simple response time and tracking experiment were detected. Biphasic alcohol response questionnaires were collected. Results After alcohol consumption, ALDH2*1/*2 group's blood ethanol and blood acetaldehyde concentration reached the peak earlier than ALDH2*1/*1 group. Its blood acetaldehyde concentration was higher than that of ALDH2*1/*1 group, 1-6 h after alcohol consumption. The psychomotor functions, such as visual selective response time and auditory simple response time in ALDH2*1/*2 group were more significantly impaired than those in ALDH2*1/*1 group after alcohol consumption. There was no statistical significance between the two groups in excitement or sedation reactions （P>0.05）. Pearson correlation coefficient test showed that blood acetaldehyde concentration was related with psychomotor function. Conclusion There are significant differences between the psychomotor function of ALDH2 wild type and mutant type individuals after alcohol consumption estimated to be related to the difference in blood acetaldehyde concentration after alcohol consumption.
Acetaldehyde/metabolism* ; Alcohol Drinking/blood* ; Aldehyde Dehydrogenase/genetics* ; Aldehyde Dehydrogenase, Mitochondrial ; Aldehyde Oxidoreductases ; Ethanol/metabolism* ; Genotype ; Humans ; Polymorphism, Genetic/genetics* ; Psychomotor Performance/physiology*

BACKGROUNDNitroglycerin (NTG) is one of the few immediate treatments for acute angina. Aldehyde dehydrogenase 2 (ALDH2) is a key enzyme in the human body that facilitates the biological metabolism of NTG. The biological mechanism of NTG serves an important function in NTG efficacy. Some reports still contradict the results that the correlation between ALDH2 gene polymorphisms and NTG and its clinical efficacy is different. However, data on NTG measurement by pain relief are subjective. This study aimed to investigate the influence of ALDH2 gene polymorphism on intervention with sublingual NTG using noninvasive hemodynamic parameters of cardiac output (CO) and systemic vascular resistance (SVR) in Northern Chinese Han population.

METHODSThis study selected 559 patients from the Affiliated Hospital of Qingdao University. A total of 203 patients presented with coronary heart disease (CHD) and 356 had non-CHD (NCHD) cases. All patient ALDH2 genotypes (G504A) were detected and divided into two types: Wild (GG) and mutant (GA/AA). Among the CHD group, 103 were wild-type cases, and 100 were mutant-type cases. Moreover, 196 cases were wild-type, and 160 cases were mutant type among the NCHD volunteers. A noninvasive hemodynamic detector was used to monitor the CO and the SVR at the 0, 5, and 15 minute time points after medication with 0.5 mg sublingual NTG. Two CO and SVR indicators were used for a comparative analysis of all case genotypes.

RESULTSBoth CO and SVR indicators significantly differed between the wild and mutant genotypes at various time points after intervention with sublingual NTG at 5 and 15 minutes in the NCHD (F = 16.460, 15.003, P = 0.000, 0.000) and CHD groups (F = 194.482, 60.582, P = 0.000, 0.000). All CO values in the wild-type case of both NCHD and CHD groups increased, whereas those in the mutant type decreased. The CO and ΔCO differences were statistically significant (P < 0.05; P < 0.05). The SVR and ΔSVR changed between the wild- and mutant-type cases at all-time points in both NCHD and CHD groups had statistically significant differences (P < 0.05; P < 0.05).

CONCLUSIONALDH2 (G504A) gene polymorphism is associated with changes in noninvasive hemodynamic parameters (i.e. CO and SVR) after intervention with sublingual NTG. This gene polymorphism may influence the effect of NTG intervention on Northern Chinese Han population.

Aged ; Aldehyde Dehydrogenase ; genetics ; Aldehyde Dehydrogenase, Mitochondrial ; Asian Continental Ancestry Group ; Female ; Hemodynamics ; drug effects ; genetics ; physiology ; Humans ; Male ; Middle Aged ; Nitroglycerin ; pharmacology ; Polymorphism, Genetic ; genetics

OBJECTIVETo study the distribution of aldehyde dehydrogenase-2 (ALDH2) polymorphisms between healthy Zhuang and Han ethnic individuals in Guangxi Autonomous Region and its influence to the behaviors of alcohol consumption.

METHODSPolymerase chain reaction with confronting two-pair primers (PCR-CTPP) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques were used to genotype ALDH2, respectively, and alcohol consumption was recorded in a constructed questionnaire.

RESULTSThe frequencies of ALDH2 alleles (ALDH2(1)/ALDH2(2)) among Zhuang and Han ethnics were 0.511, 0.489 and 0.508, 0.492 respectively (chi2 = 0.001, P > 0.05). The ALDH2 genotypes were verified with PCR-RFLP method. The frequencies of ALDH2(1) genotype in alcoholics (> or = 3 times drinking per week) were 35.59% and 15.67% in Zhuang and Han groups respectively (chi2 = 5.800, P = 0.016).

CONCLUSIONThere was no significant different distribution of ALDH2 genotype among healthy Zhuang and Han ethnic people. The genotype of ALDH2 in different ethnicity might influence individual behavior of alcohol consumption.

Adult ; Aldehyde Dehydrogenase ; genetics ; Aldehyde Dehydrogenase, Mitochondrial ; Alleles ; China ; DNA Primers ; genetics ; Female ; Gene Frequency ; Genotype ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; methods ; Polymorphism, Restriction Fragment Length

OBJECTIVE: To investigate the correlation between aldehyde dehydrogenase 2 (ALDH2) rs671 polymorphisms and chemotherapy-induced nausea and vomiting (CINV). METHODS: A total of 90 Chinese patients with malignant tumors receiving chemotherapy for the first time were recruited in this study. The occurrence of CINV was observed within 120 h after treatment with docetaxel and cis-platinum chemotherapy (DP regimen). The data of the patients (including age, gender, tumor stage, habitual alcohol consumption, motion sickness, morning sickness, and average sleep time prior to chemotherapy) were collected through a questionnaire. ALDH2 rs671 polymorphisms of the patients were analyzed using a multiple single nucleotide polymorphism genotyping, and the Hardy-Weinberg equation was used for genetic linkage analysis. The correlations between the factors including ALDH2 rs671 polymorphisms and the occurrence of CINV were analyzed. RESULTS: The incidence of CINV was 48.9% among the patients receiving their first chemotherapy with DP regimen. Univariate analysis indicated that the genetic polymorphisms of ALDH2 rs671 were significantly correlated with the occurrence of CINV (P < 0.05). Multivariate logistic analysis indicated that ALDH2 rs671 mutation (OR: 3.019, 95% CI: 1.056-8.628, P < 0.05) and average sleep time prior to chemotherapy no longer than 6 h (OR: 2.807, 95% CI: 1.033-7.628, P < 0.05) were risk factors for CINV in patients with malignant tumors receiving the first chemotherapy with DP regimen. CONCLUSION ALDH2 gene mutation at rs671 is a risk factor contributing to the occurrence of CINV, and understanding of the underlying mechanism may help to more effectively control the occurrence of CINV.
Humans ; Aldehyde Dehydrogenase, Mitochondrial/genetics* ; Antineoplastic Agents/adverse effects* ; Nausea/genetics* ; Polymorphism, Single Nucleotide ; Vomiting/genetics* ; Neoplasms/drug therapy*

OBJECTIVETo investigate the association of the polymorphisms of aldehyde dehydrogenase-2(ALDH2) and CYP2E1-RsaI genes and alcohol consumption with oral squamous cell carcinoma (OSCC).

METHODSThe genetic polymorphisms of ALDH2 and CYP2E1-RsaI were determined by polymorphism-polymerase chain reaction (PCR) technique in the peripheral blood leukocytes of 320 OSCC patients and 320 non-cancer controls.

RESULTSThe frequencies of ALDH2 variant genotypes and CYP2E1-RsaI (c2/c2) were 70.94% and 39.06% in the OSCC group and 43.44% and 20.62% in the control group (both P<0.01). The risk of OSCC with ALDH2 variant genotypes was significantly higher than that in control group (OR=3.178, 95% CI=1.917-4.749), whereas the subjects carried with CYP2E1-RsaI (c2/c2) also had a high risk of OSCC (OR=2.467, 95%CI=1.783-4.045). Combined analysis of the polymorphisms showed that percentage of ALDH2 variant genotypes/CYP2E1-RsaI (c2/c2) in OSCC group and control group was 32.19% and 6.25%, respectively (P<0.01). Carriers of ALDH2 variant genotypes/CYP2E1-RsaI (c2/c2) had a high risk of OSCC (OR=9.792, 95%CI=3.583-12.472). The percentage of alcohol consumption was significantly higher in OSCC group than in the control group (OR=2.861, 95% CI=1.541-4.781, P<0.01), and ALDH2 variant genotypes and CYP2E1-RsaI (c2/c2) showed synergic effects with alcohol consumption for the increased risk of OSCC (OR=41.152, 95%CI=19.903-67.551).

CONCLUSIONThe polymorphisms of ALDH2 and CYP2E1-RsaI genes and alcohol consumption, independently and synergically, increase the risk of OSCC.

Alcohol Drinking ; adverse effects ; Aldehyde Dehydrogenase ; Aldehyde Dehydrogenase, Mitochondrial ; Carcinoma, Squamous Cell ; etiology ; genetics ; Cytochrome P-450 CYP2E1 ; genetics ; Female ; Humans ; Male ; Middle Aged ; Mouth Neoplasms ; etiology ; genetics ; Polymorphism, Genetic ; Risk Factors

OBJECTIVETo study the relationship between occupational hazard susceptibility of formaldehyde and genetic polymorphisms of ALDH2 and CYP2E1.

METHODSGenotypes of ALDH2 and CYP2E1 (Rsa I/Pst I site) of 107 subjects exposed to formaldehyde were determined with PCR-RFLP through testing peripheral blood lymphocytes, and the concentration of air formaldehyde in workplace and urine formic acid of the subjects were measured with HPLC. The relationship between genotypes and the urine formic acid increment was analyzed with nonparametric rank sum testing.

RESULTSThe concentration of urine formic acid increment was related with ALDH2 genotypes (chi2 = 9.241, P < 0.05), and the means of urinary formic acid of subjects with GG, GA, AA genotype were (15.84 +/- 6.86), (12.06 +/- 7.94) and (7.31 +/- 5.37) mg/g creatinine, respectively. Mann-Whitney U test showed the formic acid increment between allele G homozygotes and allele A homozygotes was significantly different (U=26, P= 0.033). Our data indicated that the formaldehyde metabolism of ALDH2 GG homozygotic genotype was more active than ALDH2 AA homozygotic genotype(the difference of the two mean rank was 13.30). But the polymorphism of Rsa I / Pst I site of CYP2E1 5'-franking region was not correlated with the concentration of urine formic acid (chi2 = 4.285, P=0.117), and the urinary formic acid means of subjects with C1/C1, C1/C2, C2/C2 genotype were (11.14 +/- 7.91), (12.13 +/- 8.16) and (16.51 -/+ 3.78) mg/g creatinine, respectively. By Stepwise Multiple Regression Analysis, it showed that the urinary formic acid increment might be influenced by FA exposure concentration and ALDH2 genotype, and the model's R2 was 0.196.

CONCLUSIONThe metabolism of formaldehyde in human body was related with the genotypes of ALDH2, but not with the CYP2E1 (Rsa I/Pst I) polymorphisms.

Adolescent ; Adult ; Aldehyde Dehydrogenase ; genetics ; Aldehyde Dehydrogenase, Mitochondrial ; Alleles ; Cytochrome P-450 CYP2E1 ; genetics ; Disease Susceptibility ; Female ; Formaldehyde ; metabolism ; Gene Frequency ; Genotype ; Humans ; Male ; Occupational Exposure ; Polymorphism, Genetic ; Risk Factors

PURPOSE: The aldehyde dehydrogenase 2 (ALDH2) gene has been implicated in the development of alcoholic liver cirrhosis (ALC) in East Asians. However, the results are inconsistent. In this study, a meta-analysis was performed to assess the associations between the ALDH2 polymorphism and the risk of ALC. MATERIALS AND METHODS: Relevant studies were retrieved by searching PubMed, Web of Science, CNKI, Wanfang and Veipu databases up to January 10, 2015. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using either the fixed- or random effects model. RESULTS: A total of twelve case-control studies included 1003 cases and 2011 controls were included. Overall, the ALDH2 polymorphism was associated with a decreased risk of ALC (*1/*2 vs. *1/*1: OR=0.78, 95% CI: 0.61-0.99). However, in stratification analysis by country, we failed to detect any association among Chinese, Korean or Japanese populations. CONCLUSION: The pooled evidence suggests that ALDH2 polymorphism may be an important protective factor for ALC in East Asians.
Aldehyde Dehydrogenase, Mitochondrial/*genetics ; Asian Continental Ancestry Group/*genetics ; Case-Control Studies ; Genetic Predisposition to Disease ; Humans ; Liver Cirrhosis, Alcoholic/*ethnology/*genetics ; Odds Ratio ; Polymorphism, Genetic/*genetics ; Protective Factors

OBJECTIVETo investigate whether activation of mitochondrial aldehyde dehydrogenase 2 (ALDH2) and inhibition of mitochondrial permeability transition pore (mitoPTP) were involved in the cardioprotection of ethanol postconditioning in isolated rat heart.

METHODSHearts isolated from male Sprague-Dawley rats were perfused on a langendorff apparatus and subjected to 30 min of regional ischemia (occlusion of left anterior descending artery) followed by 120 min of reperfusion. The ventricular hemodynamic parameters and lactate dehydrogenase (LDH) release during reperfusion were measured. Infarct size was measured by TTC staining method and the expression of ALDH2 at mRNA level of left anterior myocardium was detected by RT-PCR.

RESULTIn contrast to ischemia and reperfusion, ethanol postconditioning improved the recovery of left ventricular developed pressure, maximal rise/fall rate of left ventricular pressure during reperfusion, reduced LDH release and infarct size. The expression of ALDH2 mRNA level was increased. Administration of mitoPTP activator atractyloside attenuated the effect of ethanol postconditioning, LDH release and infarct size were increased, and the recovery of hemodynamic parameters was inhibited. The expression of ALDH2 mRNA was decreased.

CONCLUSIONEthanol postconditioning has cardioprotection effect, which may be associated with upregulating mitochondrial ALDH2 mRNA expression and inhibiting the opening of mitochondrial permeability transition pore.

Aldehyde Dehydrogenase ; drug effects ; genetics ; metabolism ; Aldehyde Dehydrogenase, Mitochondrial ; Animals ; Ethanol ; pharmacology ; In Vitro Techniques ; Ischemic Postconditioning ; L-Lactate Dehydrogenase ; metabolism ; Male ; Mitochondria, Heart ; drug effects ; metabolism ; Mitochondrial Membrane Transport Proteins ; drug effects ; metabolism ; Mitochondrial Proteins ; drug effects ; genetics ; metabolism ; Myocardial Reperfusion Injury ; metabolism ; pathology ; prevention & control ; Myocardium ; metabolism ; pathology ; RNA, Messenger ; genetics ; Rats ; Rats, Sprague-Dawley