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Alcoholism: Clinical and Experimental Research | 2008

Salivary Acetaldehyde Concentration According to Alcoholic Beverage Consumed and Aldehyde Dehydrogenase-2 Genotype

Akira Yokoyama; Eri Tsutsumi; Hiromi Imazeki; Yoshihide Suwa; Chizu Nakamura; Takeshi Mizukami; Tetsuji Yokoyama

BACKGROUND Acetaldehyde is suspected of playing a critical role in cancer development in the upper aerodigestive tract (UADT). The high salivary acetaldehyde levels after alcohol drinking are partly due to acetaldehyde production by oral bacteria. Some alcoholic beverages, especially Calvados and shochu, contain very high levels of acetaldehyde. Inactive heterozygous aldehyde dehydrogenase-2 (ALDH2) increases the risk of UADT cancer in drinkers. METHODS In a randomized cross-over design study, 19 healthy Japanese volunteers ingested 0.6 g ethanol/kg body weight in the form of 13% ethanol Calvados, 13% ethanol shochu, 13% ethanol red wine, and 5% ethanol beer under the fasting conditions at 3-week intervals. We monitored blood and salivary acetaldehyde concentrations immediately after drinking, and 30, 60, 90, 120, and 180 minutes after completion of drinking. RESULTS The acetaldehyde concentration of each beverage was: Calvados 0.60 mM (1.86 mM in 40% undiluted solution), shochu 0.60 mM (1.16 mM in 25% undiluted solution), red wine 0.25 mM, and beer 0.14 mM. The salivary acetaldehyde concentration immediately after drinking wine was significantly lower than the other beverages, and it was significantly lower immediately after drinking beer than Calvados. The acetaldehyde concentrations 30 to 180 minutes after drinking were unrelated to the beverage type. Throughout the observation period the salivary acetaldehyde concentrations were much higher than the blood acetaldehyde concentrations in all 12 active ALDH2 homozygotes (24 to 53 microM in saliva vs. 2 to 5 microM in blood) and in all 7 inactive ALDH2 heterozygotes (37 to 76 microM in saliva vs. 12 to 25 microM in blood), and they were 13 to 25 microM higher in the ALDH2 heterozygotes than in the ALDH2 homozygotes after adjusting for age, body weight, sex, smoking and drinking habits, and time since the last toothbrushing. The values after subtracting the blood acetaldehyde concentration from the salivary acetaldehyde concentration were also higher in the ALDH2 heterozygotes than in the ALDH2 homozygotes. CONCLUSIONS There are differences in exposure of the UADT to high salivary acetaldehyde concentrations according to the type of alcoholic beverage and ALDH2 genotype, and the differences partly explain the differences in the cancer susceptibility of the UADT according to alcoholic beverage and ALDH2 genotype.


Cancer Epidemiology, Biomarkers & Prevention | 2006

Risk of Squamous Cell Carcinoma of the Upper Aerodigestive Tract in Cancer-Free Alcoholic Japanese Men: An Endoscopic Follow-up Study

Akira Yokoyama; Tai Omori; Tetsuji Yokoyama; Yasuo Sato; Takeshi Mizukami; Sachio Matsushita; Susumu Higuchi; Katsuya Maruyama; Hiromasa Ishii; Toshifumi Hibi

Asian case-control studies have shown a strong relationship between the development of squamous cell carcinoma (SCC) of the esophagus and alcohol consumption combined with inactive aldehyde dehydrogenase-2 (ALDH2*1/*2), less-active alcohol dehydrogenase-1B (ADH1B*1/*1), high mean corpuscular volume (MCV), and self-reported facial flushing in response to alcohol. However, little is known about whether these risk factors prospectively influence cancer development in cancer-free alcoholics. Between 1993 and 2005, 808 Japanese alcoholic men diagnosed as cancer-free by an initial endoscopic screening examination received follow-up examinations ranging from 1 to 148 months (median, 31 months) later, and SCC of the upper aerodigestive tract was diagnosed in 53 of them (esophagus in 33 and oropharyngolarynx in 30). Cox proportional hazards analysis showed that the age-adjusted relative hazard for SCC was 11.55 [95% confidence interval (95% CI), 5.73-23.3] in ALDH2*1/*2 heterozygotes compared with ALDH2*1/*1 homozygotes, 2.02 (95% CI, 1.02-4.02) in ADH1B*1/*1 homozygotes compared with ADH1B*1/*2 heterozygotes or *2/*2 homozygotes, 2.64 (95% CI, 1.49-4.67) in patients with flushing compared with those who had never experienced flushing, 2.91 (95% CI, 1.63-5.20) in those with an MCV ≥ 106 compared with those with an MCV < 106, 2.52 (95% CI, 1.22-5.22) in those who smoked ≥30 cigarettes per day compared with those who smoked 0 to 19 cigarettes per day, 7.26 (95% CI, 3.99-13.23) in those with esophageal dysplasia compared with those without distinct iodine-unstained lesions ≥5 mm, and 0.28 (95% CI, 0.09-0.85) in those with body mass index ≥ 23.2 (highest quartile) compared with those with body mass index < 19.0 (lowest quartile). These predictors are useful for selecting appropriately patients for careful follow-up examinations. (Cancer Epidemiol Biomarkers Prev 2006;15(11):2209–15)


Alcoholism: Clinical and Experimental Research | 2013

Genetic Polymorphisms of Alcohol Dehydrogenase‐1B and Aldehyde Dehydrogenase‐2 and Liver Cirrhosis, Chronic Calcific Pancreatitis, Diabetes Mellitus, and Hypertension Among Japanese Alcoholic Men

Akira Yokoyama; Takeshi Mizukami; Toshifumi Matsui; Tetsuji Yokoyama; Mitsuru Kimura; Sachio Matsushita; Susumu Higuchi; Katsuya Maruyama

BACKGROUND The presence of the less-active form of alcohol dehydrogenase-1B encoded by ADH1B*1/*1 (vs. *2 allele) and active form of aldehyde dehydrogenase-2 (ALDH2) encoded by ALDH2*1/*1 (vs. *2 allele) increases the risk of alcoholism in East Asians. METHODS The subjects in this cross-sectional survey were 1,902 Japanese alcoholic men (≥40 years) who underwent ADH1B/ALDH2 genotyping. RESULTS Age-adjusted daily alcohol consumption did not differ according to the ADH1B/ALDH2 genotypes. The age-adjusted odds ratios (AORs; 95% confidence interval) for liver cirrhosis (LC; n = 359, 1.58 [1.19 to 2.09]), chronic calcific pancreatitis (CP; n = 80, 2.24 [1.20 to 4.20]), and diabetes mellitus (DM; n = 383, 1.51 [1.15 to 1.99]) were higher in the ADH1B*2 allele carriers than in the ADH1B*1/*1 carriers. The AORs for LC (1.43 [1.01 to 2.02]), CP (1.68 [0.80 to 3.53]), DM (1.63 [1.15 to 2.30]), and hypertension (HT; n = 495, 1.52 [1.11 to 2.07]) were higher in the ALDH2*1/*1 carriers than in the ALDH2*1/*2 carriers. The ADH1B*2-associated AOR for LC was 2.08 (1.46 to 2.94) among those aged 40 to 59 years, but 0.89 (0.56 to 1.43) among those aged 60 years or over, and the interaction between ADH1B genotype and age on the LC risk was significant (p = 0.009). When the group with non-LC and no/mild fibrosis was used as controls, the ADH1B*2-associated AORs increased according to the severity of their liver disease: 1.67 (1.32 to 2.11) for the group with non-LC and serum type IV collagen values ≥200 ng/ml, 1.81 (1.24 to 2.63) for the group of Child-Pugh class A LC, and 3.17 (1.98 to 5.07) for the group with Child-Pugh class B/C LC. Anti-hepatitis C virus (HCV) antibody was positive in 103 patients, and the groups with a high anti-HCV antibody titer and either the ADH1B*2/*2 genotype or the ALDH2*1/*1 genotype had the highest AORs (8.83 and 4.90, respectively). The population attributable fraction (PAF) due to the ADH1B*2 allele was 29% for LC, 47% for CP, and 27% for DM, and the PAF due to the ALDH2*1/*1 genotype was 26% for LC, 34% for DM, and 30% for HT. CONCLUSIONS The ADH1B*2 allele increased the AORs for LC, CP, and DM of the alcoholics, and the ALDH2*1/*1 genotype increased their AORs for LC, DM, and HT. HCV infection and genetic susceptibility had a synergistic effect on the AOR for LC.


Journal of Gastroenterology and Hepatology | 2007

Helicobacter pylori, chronic atrophic gastritis, inactive aldehyde dehydrogenase-2, macrocytosis and multiple upper aerodigestive tract cancers and the risk for gastric cancer in alcoholic Japanese men

Akira Yokoyama; Tetsuji Yokoyama; Tai Omori; Sachio Matsushita; Takeshi Mizukami; Hisao Takahashi; Susumu Higuchi; Katsuya Maruyama; Hiromasa Ishii; Toshifumi Hibi

Background:  Gastric carcinoma occurs at a high rate in alcoholic Japanese men. Inactive heterozygous aldehyde dehydrogenase‐2 (ALDH2*1/2*2) and macrocytosis (mean corpuscular volume [MCV] ≥ 106 fl) enhance the risk for esophageal carcinoma, which frequently occurs with gastric carcinoma in this population. Whether alcoholism affects Helicobacter pylori‐induced chronic atrophic gastritis (CAG) is unknown.


Alcoholism: Clinical and Experimental Research | 1999

Superoxide anion release into the hepatic sinusoid after an acute ethanol challenge and its attenuation by Kupffer cell depletion.

Hirokazu Yokoyama; Masahiko Fukuda; Yukishige Okamura; Takeshi Mizukami; Hideki Ohgo; Yoshitaka Kamegaya; Shinzo Kato; Hiromasa Ishii

Superoxide anion release into the hepatic sinusoids and subsequent damage to the endothelial cells of the hepatic sinusoids after ethanol challenge was examined. A 250 mg/kg body weight/hr dose of ethanol was given to rats for 3 hr, and superoxide anion release into the hepatic sinusoids was examined in a liver perfusion model using the cytochrome c method. Ethanol treatment resulted in superoxide anion release into the hepatic sinusoids (0.20 ± 0.01 vs. 0.12 ± 0.02 o.d., p< 0.05) and an increase in the purine nucleoside phosphorylase/alanine aminotransferase ratio in the liver perfusate, a marker of damage to the endothelial cells of the hepatic sinusoids (0.003 ± 0.002 vs. 0.008 ± 0.002; p < 0.05). Tumor necrosis factor-alpha was not detectable in either group, and there were no significant differences in the population of hepatic macrophages, leukocytes, or Kupffer cells between the two groups. To clarify the role of Kupffer cells in the mechanism, 10 mg/kg of body weight of gadolinium chloride was given to rats twice, 24 hr apart, resulting in depletion of ED2-positive cells from the hepatic lobules. The superoxide anion release after the ethanol challenge was significantly attenuated in the Kupffer cell-depleted rats, compared with the controls (0.14 ±0.02;p <0.05, compared with ethanol alone). The change was associated with a significant decrease in the purine nucleoside phosphorylase/alanine aminotransferase ratio in the liver perfusate (0.004 ± 0.002; p < 0.05, compared with ethanol alone). Ethanol causes superoxide anion release into the hepatic sinusoid and subsequent damage to the sinusoidal endothelial cells. These changes were reduced by Kupffer cell depletion. This supports the view that Kupffer cell depletion has a protective effect on ethanol-induced liver injury.


Alcoholism: Clinical and Experimental Research | 2013

Alcohol dehydrogenase-1B genotype (rs1229984) is a strong determinant of the relationship between body weight and alcohol intake in Japanese alcoholic men.

Akira Yokoyama; Tetsuji Yokoyama; Toshifumi Matsui; Takeshi Mizukami; Sachio Matsushita; Susumu Higuchi; Katsuya Maruyama

BACKGROUND The calories in alcoholic beverages consumed by alcoholics are a major energy source and a strong modifier of their body weight. Genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B) and aldehyde dehydrogenase-2 (ALDH2) affect susceptibility to alcoholism and may affect body weight via gene-associated differences in fuel utilization in alcoholics. METHODS We evaluated associations between ADH1B/ALDH2 genotypes and the body weight and body mass index (BMI) of 1,301 Japanese alcoholic men at the time of their first visit to an addiction center. RESULTS Median (25th to 75th) caloric intake in the form of alcoholic beverages was 864 (588 to 1,176) kcal/d. Age-adjusted caloric intake did not differ according to ADH1B/ALDH2 genotypes. The body weight and BMI values showed that the ADH1B*2/*2 and *1/*2 carriers (n = 939) were significantly leaner than the ADH1B*1/*1 carriers (n = 362) irrespective of age, drinking, smoking, and dietary habits. The age-adjusted body weight values of the ADH1B*2/*2, ADH1B*1/*2, and ADH1B*1/*1 carriers were 58.4 ± 0.4, 58.7 ± 0.5, and 63.6 ± 0.5 kg, respectively (ADH1B*2 vs. ADH1B*1/*1 carriers, p < 0.0001), and the corresponding BMI values were 21.0 ± 0.1, 21.0 ± 0.1, and 22.9 ± 0.2 kg/m(2) , respectively (ADH1B*2 vs. ADH1B*1/*1 carriers, p < 0.0001). No effects of inactive ALDH2 on body weight or BMI were observed. A multivariate analysis showed that BMI decreased by 0.35 per 10-year increase in age, by 1.73 in the presence of the ADH1B*2 allele, by 1.55 when the preferred beverage was whiskey, and by 0.19 per +10 cigarettes/d and that it increased by 0.10 per +22 g ethanol (EtOH)/d and by 0.41 per increase in category of frequency of milk intake (every day, occasionally, rarely, and never). The increase in BMI as alcohol consumption increased was significantly smaller in the ADH1B*2 group than in the ADH1B*1/*1 group (p = 0.002). CONCLUSIONS ADH1B genotype was a strong determinant of body weight in the alcoholics. The more rapid EtOH elimination associated with the ADH1B*2 allele may result in less efficient utilization of EtOH as an energy source in alcoholics.


International Journal of Cancer | 2012

Development of squamous neoplasia in esophageal iodine-unstained lesions and the alcohol and aldehyde dehydrogenase genotypes of Japanese alcoholic men.

Akira Yokoyama; Teruyuki Hirota; Tai Omori; Tetsuji Yokoyama; Hirofumi Kawakubo; Toshifumi Matsui; Takeshi Mizukami; Shuka Mori; Hitoshi Sugiura; Katsuya Maruyama

We investigated the development of esophageal neoplasia in biopsy specimens of the distinct iodine‐unstained lesions (DIULs) ≥5 mm detected in 280 of 2,115 Japanese alcoholic men who underwent screening by esophageal iodine staining. Low‐grade intraepithelial neoplasia (LGIN) was diagnosed in 155 of them, high‐grade intraepithelial neoplasia (HGIN) in 57, and invasive SCC in 35. The size of the DIULs increased with the degree of neoplasia. Most LGINs were flat and were missed before iodine staining. Some DIULs became a light pink color (PC) about 2 min after staining, and 2.6, 56.1 and 96.0% of the LGIN, HGIN and invasive SCC lesions, respectively, were PC‐sign‐positive. Multiple DIULs of any size markedly increased the risk of LGIN [adjusted OR (95%CI) = 10.1 (7.12–14.5)], HGIN [27.9 (14.6–53.4)] and invasive SCC [21.6 (10.1–46.4)], and were strongly associated with the presence vs. absence of DIULs ≥ 5 mm [13.3 (9.21–19.1)], inactive heterozygous aldehyde dehydrogenase‐2 (ALDH2*1/*2) vs. ALDH2*1/*1 [2.60 (1.79–3.78)], and less‐active alcohol dehydrogenase‐1B (ADH1B*1/*1) vs. ADH1B*2 allele [2.61 (1.87–3.64)]. The combination of ALDH2*1/*2 and ADH1B*1/*1 synergistically increased the risk of LGIN [4.53 (2.17–9.47)], HGIN [10.4 (4.34–24.7)] and invasive SCC [21.7 (7.96–59.3)]. Esophageal neoplasia developed at earlier ages in those with ALDH2*1/*2. Biopsy‐proven HGIN was diagnosed as invasive SCC in 15 (39.5%) of 38 patients after endoscopic mucosectomy or surgery. In conclusion, large size, non‐flat appearance, positive PC sign and multiplicity of DIULs and ALDH2*1/*2 and ADH1B*1/*1 were associated with development of esophageal neoplasia in Japanese alcoholics. Biopsy‐proven HGIN should be totally resected for both diagnostic and therapeutic purposes.


Journal of Gastroenterology and Hepatology | 2004

Kupffer cell depletion attenuates superoxide anion release into the hepatic sinusoids after lipopolysaccharide treatment

Masahiko Fukuda; Hirokazu Yokoyama; Takeshi Mizukami; Hideki Ohgo; Yukishige Okamura; Yoshitaka Kamegaya; Yoshinori Horie; Shinzo Kato; Hiromasa Ishii

Background and Aim:  The mechanisms involved in the beneficial effect of gadolinium chloride against endotoxin‐induced liver damage were studied.


Journal of Gastroenterology | 2005

Esophageal melanosis, an endoscopic finding associated with squamous cell neoplasms of the upper aerodigestive tract, and inactive aldehyde dehydrogenase-2 in alcoholic Japanese men

Akira Yokoyama; Tai Omori; Tetsuji Yokoyama; Yoichi Tanaka; Takeshi Mizukami; Sachio Matsushita; Susumu Higuchi; Hisao Takahashi; Katsuya Maruyama; Hiromasa Ishii; Toshifumi Hibi

BackgroundEsophageal melanosis is often observed in alcoholic Japanese men, in whom the prevalence of squamous cell dysplasia and carcinoma (SCC) in the upper aerodigestive tract are high. This study evaluated the associations of esophageal melanosis with these neoplasms, and the factors contributing to the development of esophageal melanosis in this population.MethodsEndoscopic screening was combined with esophageal iodine staining in 1535 alcoholic Japanese men (aged 40–79 years), of whom 1007 underwent aldehyde dehydrogenase-2 (ALDH2) genotyping.ResultsFifty patients (3.3%) were diagnosed with esophageal melanosis, which had a higher incidence in those with noncancerous distinct iodine-unstained lesions (DIULs; 16/268; 6.0%), esophageal SCC (9/66; 13.6%), and oropharyngolaryngeal SCC (4/19; 21.1%) than in cancer- and DIUL-free controls (24/1182; 2.0%). The presence of esophageal melanosis was associated with higher risks for noncancerous DIULs, esophageal SCC, and oropharyngolaryngeal SCC (odds ratios, 2.81, 6.54, and 14.77, respectively). Men with the inactive ALDH2*1/2*2 genotype had a higher risk for esophageal melanosis (2.66-fold), as well as for DIULs and SCCs.ConclusionsThe presence of esophageal melanosis in alcoholic Japanese men could indicate a high risk for DIULs and SCCs in the upper aerodigestive tract. The high incidence of esophageal melanosis may be partially linked to high acetaldehyde exposure, a consequence of drinking alcohol in persons with inactive ALDH2.


Alcohol and Alcoholism | 2014

Blood Ethanol Levels of Nonabstinent Japanese Alcoholic Men in the Morning After Drinking and Their ADH1B and ALDH2 Genotypes

Akira Yokoyama; Tetsuji Yokoyama; Takeshi Mizukami; Toshifumi Matsui; Mitsuru Kimura; Sachio Matsushita; Susumu Higuchi; Katsuya Maruyama

AIMS Genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B, rs1229984) and aldehyde dehydrogenase-2 (ALDH2, rs671) affect ethanol (EtOH) metabolism and susceptibility to alcoholism. METHODS We evaluated associations between ADH1B/ALDH2 genotypes and the blood EtOH levels of 805 Japanese alcoholic men in the morning after they had drunk within the previous 34 h. RESULTS Age-adjusted usual alcohol consumption did not differ according to ADH1B/ALDH2 genotypes. Higher blood EtOH levels persisted for longer periods in the ADH1B*1/*1 carriers (n = 246) than in the ADH1B*2 carriers (n = 559). Blood EtOH levels did not differ by ALDH2 genotype. The blood EtOH levels ≥ 0.3 mg/ml (criterion for drunk driving in Japanese law) were observed (40% vs. 14-17%, P < 0.0001) in a higher proportion of the ADH1B*1/*1 carriers than of the ADH1B*2 carriers after a 12.1-to-18-h interval since the last drink. Multivariate analyses showed that the EtOH levels heightened by 0.500 mg/ml in the presence of ADH1B*1*1 and by 0.248 mg/ml in the presence of cirrhosis, and lowered by 0.120 mg/ml per 10-year age increase, by 0.087 mg/ml per 10-kg body-weight increase and by 0.673 mg/ml per 10-h interval since the last drink. The odds ratio (95% confidence interval) for an EtOH level ≥ 0.3 mg/ml was 3.44 (2.34-5.04) in the presence of ADH1B*1/*1, 2.01 (1.28-3.14) in the presence of cirrhosis, 0.59 (0.49-0.71) per 10-year age increase, 0.80 (0.68-0.95) per 10-kg body-weight increase and 0.10 (0.07-0.15) per 10-h interval since the last drink. CONCLUSION The longer-than-expected EtOH lingering in the blood of the ADH1B*1/*1 alcoholics may exacerbate alcohol-related problems, including drunk driving.

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Tetsuji Yokoyama

Tokyo Medical and Dental University

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Sachio Matsushita

National Institute for Health and Welfare

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