Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although alcohol-related flushing seems to be a genetically influenced protective factor for alcoholism in some Asian groups, little is known about whether this is true for Caucasians. The evidence for alcohol-related flushing as a protective factor for the development of alcoholism was examined in a sample of 5831 Australian twins (2041 men, 3790 women) who were administered a structured psychiatric interview. Twin correlations for self-reported adverse alcohol reactions (e.g., "flushing or blushing" and "feeling very sleepy" after drinking 1 or 2 drinks) were modest, suggesting minimal contribution of genetic factors, but when corrected for reliability of measurement, were consistent with moderate heritabilities. In accord with studies examining Asian samples, we found that individuals who experienced adverse reactions after drinking small amounts of alcohol drank less often and slightly less per drinking occasion than those who did not experience adverse reactions. However, those who experienced adverse reactions were more likely to have symptoms of alcoholism and to report a parental history of alcohol problems. We conclude that self-reported alcohol-related flushing is not a protective factor for alcoholism in Caucasians and may be a risk factor.
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PMID:Is alcohol-related flushing a protective factor for alcoholism in Caucasians? 757 78

Inherited variations in alcohol and aldehyde dehydrogenases, the principal enzymes of ethanol metabolism, have been implicated in determining susceptibility to alcoholism and alcohol-related organ damage. An association between an RFLP for the alcohol dehydrogenase-2 (ADH2) gene and alcohol-induced liver damage was demonstrated in a Caucasian population. Genotyping studies revealed an increase in the ADH3(2) allele in patients with alcohol-induced cirrhosis. PCR studies of the ALDH5 gene have demonstrated diverse polymorphism within a short segment of its coding region, with marked inter-racial variation in allele frequencies. In addition, the Caucasian alcohol-induced flushing reaction has been characterised and its relationship with phenotypic polymorphism of ALDH1 examined.
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PMID:Alcohol and acetaldehyde dehydrogenase gene polymorphism and alcoholism. 791 53

Sulfiram, a drug applied topically to treat scabies, produces effects similar to those of disulfiram after subsequent ingestion of ethanol. Disulfiram, used in aversion therapy in the treatment of alcoholism, inhibits hepatic aldehyde dehydrogenase (ALDH) causing an accumulation of acetaldehyde after ethanol ingestion. The increased tissue levels of acetaldehyde cause a spectrum of undesirable side-effects including flushing, nausea, vomiting, and tachycardia, which are referred to as the disulfiram reaction. Previous studies have shown that in vitro sulfiram is a very weak inhibitor of ALDH, but solutions of sulfiram markedly increase in potency with time. In the present study, fresh solutions of sulfiram were exposed to fluorescent room light under ambient conditions and analyzed at timed intervals by HPLC. At least eight products, including disulfiram, were formed in the light-exposed sulfiram solutions, but not in solutions kept in the dark. Structural characterization of two of the photolysis products was obtained by on-line microbore HPLC-mass spectrometry (mu LC-MS) and on-line microbore HPLC-tandem mass spectrometry (mu LC-MS/MS) using continuous flow-liquid secondary ion mass spectrometry (CF-LSIMS) as the primary ionization method. Sulfiram was converted to disulfiram at an initial rate of 0.7%/hr, and the formation of disulfiram correlated with the increase in ALDH inhibition in vitro. The results of this investigation show that while sulfiram is a weak inhibitor of ALDH in vitro, it is readily photoconverted to disulfiram, a very potent inhibitor of ALDH, which may explain the adverse reaction to ethanol after sulfiram therapy.
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PMID:Photolysis of sulfiram: a mechanism for its disulfiram-like reaction. 798 3

Disulfiram, an aldehyde dehydrogenase (ALDH) inhibitor, induces a flushing reaction upon the ingestion of ethanol, exerting aversion against alcohol that has been used in the treatment of alcoholism. This unpleasant response has been associated with an accumulation of acetaldehyde, and more recently, with an increase in vascular prostacyclin (PGI2) production. To evaluate the possibility of evoking the flushing reaction with drugs less toxic than disulfiram, we studied the effects of propranolol and dipyridamole on ALDH and PGI2. Acetaldehyde oxidation rate was assessed by gas chromatography in mitochondria from rats treated with these drugs for seven days. Prostacyclin generation was determined in rat aortic rings incubated in Krebs-Ringer with these drugs separately and associated to acetaldehyde, and measured by radioimmunoassay of 6-keto-PGF1 alpha. Propranolol inhibited acetaldehyde oxidation rate whereas dipyridamole did not. Furthermore, propranolol increased blood acetaldehyde levels without affecting ethanol elimination rate. Both drugs stimulated prostacyclin synthesis but only dipyridamole enhanced the stimulatory effect of acetaldehyde on vascular prostacyclin production. These results strongly suggest the possibility of producing a deterrent effect on the consumption of alcohol by using propranolol or dipyridamole. In contrast to disulfiram, these drugs could potentially induce the flushing reaction in humans in the presence of low acetaldehyde concentrations; this new therapeutic approach might have an important clinical and toxicological relevance.
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PMID:Investigations on the ethanol-induced flushing reaction: effects of propranolol and dipyridamole on acetaldehyde and prostacyclin metabolism. 802 34

The aims of this study are to investigate whether self-reported facial flushing postalcohol consumption (PAC) among subjects with ALDH2*1/*1 can be attributed to ADH2 or ADH3 and whether the prediction of ALDH2 genotype can be improved by examining the combination of flushing and other accompanying reactions of PAC sensitivity. Fifty-eight subjects of Han ancestry in Taiwan were interviewed for alcohol-sensitivity reactions and their blood samples were genotyped for ALDH2, ADH2, and ADH3. For subjects with ALDH2*1/*1 (n = 46), 70% reported to have no flushing PAC and 30% reported flushing PAC. When subjects with ALDH2*1/*1 had ADH2*1/*1 (n = 11), all reported to have no flushing; otherwise, 35% (for ADH2*1/*2, n = 17) and 44% (for ADH2*2/*2, n = 18) reported flushing. For subjects with ALDH2*1/*1 and at least one ADH2*2 allele, the genotype of ADH3 was not associated with self-reported flushing. PAC flushers with ALDH2*1/*1 (50%) were more likely to report nausea than those with ALDH2*1/*2 (8%). The probability of ALDH2*1/*1 given flushing reported was 0.29, while the probability of ALDH2*1/*1 given both flushing and nausea reported was 0.71. The results indicate that self-reported flushing is determined by both ALDH2 and ADH2 and that prediction of ALDH2 genotype on the basis of self-reported flushing and nausea can help identify subjects at increased risk for alcoholism.
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PMID:Self-reported flushing and genotypes of ALDH2, ADH2, and ADH3 among Taiwanese Han. 972 71

The characteristics of alcohol-induced flushing response were studied in some Siberian Native populations (Chukchi, Eskimo, Jakuts, Udege, and Nanaian). Flushing peculiarities were estimated and the interrelationship with drinking patterns, the ethanol patch test (EPT), and somatic disorders were analyzed. Frequency of flushing response varied from 9.0% to 66.7%, and was more often apparent among females. Only the Nanaian demonstrated typical flushing, which did not allow them to consume high doses of alcohol. In the rest of the populations flushing was "atypical," i.e., appearing sometimes after high doses of alcohol but not interrupting alcohol drinking, and not associated with a positive EPT. Direct genotyping in DNA samples of Chukotka Natives did not reveal atypical allele aldehyde dehydrogenase (AIDH 2/2). Frequencies of alcohol problems, alcohol dependence symptoms, and somatic disorders (arterial hypertension, silent ischemia, diffuse liver lesions, and noncalculous cholecystitis) were higher among atypical flushers compared to nonflushers (p < 0.05-0.01). The mechanism of the observed atypical flushing response is unknown. We speculate on its hereditary nature, since flushing alcoholics, compared to nonflushers, reported that their parents had flushing responses significantly more often. Further studies are required.
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PMID:Flushing response and its role in alcohol disease in Siberian populations. 1009 24

Alcohol and histamine metabolic pathways in the body have the common enzymes aldehyde dehydrogenase and aldehyde oxidase. The metabolite of ethanol, acetaldehyde, can effectively compete with the metabolites of histamine, methylimidazole acetaldehyde, and imidazole acetaldehyde. At the periphery, alcohol and acetaldehyde liberate histamine from its store in mast cells and depress histamine elimination by inhibiting diamine oxidase, resulting in elevated histamine levels in tissues. Histamine mediates alcohol-induced gastric and intestinal damage and bronchial asthma as well as flushing in Orientals. On the other hand, alcohol provokes food-induced histaminosis and histamine intolerance, which is an epidemiological problem. There are many controversial reports concerning the effect of H2 receptor antagonists on ethanol metabolism and the activity of alcohol dehydrogenase in the stomach. In addition, alcohol affects histamine levels in the brain by modulating histamine synthesis, release, and turnover. Histamine receptor antagonists can affect ethanol metabolism and change the sensitivity of animals to the hypnotic effects of alcohol. In contrast to other neurotransmitters, the involvement of the brain histamine system in the mechanisms of the central actions of alcohol and in the pathogenesis of alcoholism is poorly studied and understood.
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PMID:Alcohol-histamine interactions. 1034 73

Several possible risk factors for ICD-10 alcohol dependence were studied by comparing cases (117 men, 188 women) with controls (248 men, 300 women). Logistic regression analyses showed that parental alcohol problems and high trait anxiety were significantly related to high occurrence of alcohol dependence in both men and women. In women, high antisocial behaviour, high impulsivity, and high externality were also related to high occurrence of alcohol dependence. High facial flushing and high stimulation when intoxicated were related to low occurrence of alcohol dependence in both men and women. In men, this was also the case for high social support. Several interactions were observed. In contrast to earlier studies, there was no significant association between alcohol dependence and left-handedness.
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PMID:Risk factors for alcohol dependence: a case-control study. 1078 96

Using a dipole tracing method based on the two-dipole model, the purpose of the present study was to investigate alcohol-induced changes in the alpha band of electroencephalogram (EEG) and its equivalent current dipoles (ECDs) in 12 healthy male volunteers, who were genetically typed for mitochondrial aldehyde dehydrogenase-2 (ALDH2). The alpha power and the mean interval dipolarity, which represents the goodness of fit of alpha EEG with the two-dipole model, increased at 30 min after 0.75 ml/kg of alcohol ingestion, when breath alcohol concentration showed its peak. However, the location of ECDs and distribution of alpha EEG did not change after alcohol ingestion. These findings indicate that alcohol enhances alpha EEG but does not change the location of its electrical sources. Interestingly, the time course of alcohol-induced EEG changes differed significantly according to the aversive flushing reaction after its intake. From 60 to 120 min, the non-flushing group which had homozygous ALDH2* 1 (active type) displayed significant increase not only in the alpha power but also in the interval dipolarity compared to the baseline, whereas the flushing group with heterozygous ALDH2*1/2*2 (inactive type) did not exhibit this significant increase. The difference in the time course was discussed from the viewpoint of the protective effect of ALDH2*2 allele against the risk for alcoholism. These results suggest that the dipole tracing method could provide an alternative neurophysiological marker for the risk for alcoholism.
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PMID:Dipole estimation of alpha EEG during alcohol ingestion in males genotypes for ALDH2. 1095 50

Multiple forms and gene loci of human alcohol dehydrogenase (ADH EC: 1.2.1.3) and aldehyde dehydrogenase (ALDH, EC: 1.2.1.3) in the major pathway of alcohol metabolism have been found and characterized in the last two decades. With the coenzyme NAD, these enzymes catalyze the reversible conversion of organic alcohols to ketones or aldehydes, and aldehyde to acetic acid. The ADH genes are mapped to chromosome 4p21-25, but the ALDH genes are localized at different chromosomes. The cytochrome P450 2E1 (CYP2E1) gene, which is mapped to chromosome 10q24.3-qter contributes also the conversion of ethanol to acetaldehyde. Genetic polymorphisms have been reported in these alcohol metabolizing enzymes. The metabolisms of alcohol and acetaldehyde in liver and blood after drinking alcohol are thought to be influenced by the interactive action of these enzymes. Amongst the five major classes of the ADH subunits (alpha, beta, gamma, pi, chi, sigma), beta and gamma subunits show genetic polymorphisms. Recently a new nomenclature for ALDH genes has been recommend based on divergent evolution and chromosomal mapping. Two major isoforms designated as cytosolic ALDH1 and mitochondrial ALDH2 can be distinguished by their electrophoretic and kinetic properties as well as by their subcellular localization. Mitochondrial ALDH2 is a major enzyme in the oxidation of acetaldehyde derived from ethanol metabolism. The catalytic deficiency of ALDH2 isozyme is responsible for flushing and other vasomotor symptoms caused by higher acetaldehyde levels after alcohol intake. So far, frequencies of the two alleles of ALDH2 in Mongoloid have been reported in the different population groups. The catalytic deficiency of ALDH2 is caused by a structural point mutation at amino acid position 487, where a substitution of Glu to Lys resulting from a transition of G (C) to A (T) at 1510 nucleotide from the initiation codon has occurred. Individuals deficient in ALDH2 activity refrain from excessive drinking of alcohol due to the aversive reactions, leading to protection against alcoholism. Prevalence of the ALDH2*1 allele is associated with alcoholism, and subsequent studies have confirmed the allelic association with alcoholism in different ethnic groups. The effects of polymorphisms of ADH2 and CYP2E1 remained controversial, even in the same ethnic group. Investigation of mutations for the transacting cis-element in promoter region of the ALDH2 gene will provide important information with respect to regulation of this gene. Transfection assays using the first 600 bp of the upstream nucleotide sequences indicated that a region from -75 to -120 was necessary for the ALDH2 gene expression, and especially NF-Y/CP1 binding site from -92 to -96 (CCAAT box) is important in the expression of the gene. A novel polymorphism due to the nucleotide replacement at -357 G to A was found in all the population groups. Alcoholism is thought to be a multifactorial disease with complex mode of inheritance in addition to psychological and social factors, and many studies of family, adoption and twins concerning alcoholism have revealed that hereditary factor is an important determinant for developing alcoholism. Genetic association studies have contributed to the identification of a number of genetic risk factors for the chronic diseases influenced by genetic disorders and environmental factors.
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PMID:[Classification of alcohol metabolizing enzymes and polymorphisms--specificity in Japanese]. 1139 42


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