Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1332347 (ADH)
 2,230 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alcohol dehydrogenase (ADH; EC 1.1.1.1) and aldehyde dehydrogenase (ALDH; EC 1.2.1.3.) are important enzymes involved in the biotransformation of both alcohols and aldehydes. Today, six classes of ADH and twelve classes of ALDH have been defined in mammals. Here we report the detection and localisation of three classes of ADH and two classes of ALDH in human skin, using Western blot analysis and immunohistochemistry with class-specific antisera. Western blot analysis of human skin cytosol revealed that class I-III ADH and class 1 and class 3 ALDH enzymes are expressed, constitutively, in three different anatomical regions of human skin (foreskin, breast, abdomen). Densitometric analysis of the immunoreactive bands revealed differential constitutive expression of these enzymes in foreskin, breast, and abdomen skin. Immunohistochemistry showed the presence of class I ADH and class III ADH enzymes, predominantly in the epidermis with some localised expression in the dermal appendages of human skin. In comparison, staining for class II ADH was more faint in the epidermis with very little dermal expression. Class 1 ALDH and class 3 ALDH were predominantly localised to the epidermis with minimal, highly localised dermal appendageal expression. These cutaneous ADH and ALDH enzymes may play significant roles in the metabolism of endogenous or xenobiotic alcohols and aldehydes.
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PMID:Expression and localization of human alcohol and aldehyde dehydrogenase enzymes in skin. 1040 30

It is already known that kinetic resolution of racemic glycidol (2,3-epoxy-1-propanol) takes place when Acetobacter pasteurianus oxidizes the compound to glycidic acid (2,3-epoxy-propionic acid) with glycidaldehyde (2,3-epoxy-propanal) proposed to be the transient seen in this conversion. Since inhibition affects the feasibility of a process based on this conversion in a negative sense, and the chemical reactivity of glycidaldehyde predicts that it could be the cause for the phenomena observed, it is important to know which enzyme(s) oxidise(s) this compound. To study this, rac.- as well as (R)-glycidaldehyde were prepared by chemical synthesis and analytical methods developed for their determination. It appears that purified quinohemoprotein alcohol dehydrogenase (QH-ADH type II), the enzyme responsible for the kinetic resolution of rac.-glycidol, also catalyses the oxidation of glycidaldehyde. In addition, a preparation exhibiting dye-linked aldehyde dehydrogenase activity for acetaldehyde, most probably originating from molybdohemoprotein aldehyde dehydrogenase (ALDH), which has been described for other Acetic acid bacteria, oxidised glycidaldehyde as well with a preference for the (R)-enantiomer, the selectivity quantified by an enantiomeric ratio (E) value of 7. From a comparison of the apparent kinetic parameter values of QH-ADH and ALDH, it is concluded that ALDH is mainly responsible for the removal of glycidaldehyde in conversions of glycidol catalysed by A. pasteurianus cells. It is shown that the transient observed in rac.-glycidol conversion by whole cells, is indeed (R)-glycidaldehyde. Since both QH-ADH and ALDH are responsible for vinegar production from ethanol by Acetobacters, growth and induction conditions optimal for this process seem also suited to yield cells with high catalytic performance with respect to kinetic resolution of glycidol and prevention of formation of inhibitory concentrations glycidaldehyde.
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PMID:Enzymes involved in the glycidaldehyde (2,3-epoxy-propanal) oxidation step in the kinetic resolution of racemic glycidol (2,3-epoxy-1-propanol) by Acetobacter pasteurianus. 1116 17

Kupffer cells are known to participate in the early events of liver injury involving lipid peroxidation. 4-Hydroxy-2,3-(E)-nonenal (4-HNE), a major aldehydic product of lipid peroxidation, has been shown to modulate numerous cellular systems and is implicated in the pathogenesis of chemically induced liver damage. The purpose of this study was to characterize the metabolic ability of Kupffer cells to detoxify 4-HNE through oxidative (aldehyde dehydrogenase; ALDH), reductive (alcohol dehydrogenase; ADH), and conjugative (glutathione S-transferase; GST) pathways. Aldehyde dehydrogenase and GST activity was observed, while ADH activity was not detectable in isolated Kupffer cells. Additionally, immunoblots demonstrated that Kupffer cells contain ALDH 1 and ALDH 2 isoforms as well as GST A4-4, P1-1, Ya, and Yb. The cytotoxicity of 4-HNE on Kupffer cells was assessed and the TD50 value of 32.5+/-2.2 microM for 4-HNE was determined. HPLC measurement of 4-HNE metabolism using suspensions of Kupffer cells incubated with 25 microLM 4-HNE indicated a loss of 4-HNE over the 30-min time period. Subsequent production of 4-hydroxy-2-nonenoic acid (HNA) suggested the involvement of the ALDH enzyme system and formation of the 4-HNE-glutathione conjugate implicated GST-mediated catalysis. The basal level of glutathione in Kupffer cells (1.33+/-0.3 nmol of glutathione per 10(6) cells) decreased significantly during incubation with 4-HNE concurrent with formation of the 4-HNE-glutathione conjugate. These data demonstrate that oxidative and conjugative pathways are primarily responsible for the metabolism of 4-HNE in Kupffer cells. However, this cell type is characterized by a relatively low capacity to metabolize 4-HNE in comparison to other liver cell types. Collectively, these data suggest that Kupffer cells are potentially vulnerable to the increased concentrations of 4-HNE occurring during oxidative stress.
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PMID:Metabolism of 4-hydroxynonenal by rat Kupffer cells. 1137 Jun 75

Alcohol dehydrogenase and aldehyde dehydrogenase (ADH and ALDH) have been coencapsulated into mouse erythrocytes by an electroporation technique. The optimal conditions were achieved as follows: 420 V, four pulses of 1 ms every 15 min. at 37 degrees C, completed by resealing: 1 h at 37 degrees C. An encapsulation yield ranging from 11-12% was obtained for ADH+ALDH-loaded erythrocytes. Carrier cell recovery was 52%. Electroporated-RBCs observed under Scanning electron microscopy exhibited a tendency toward invaginated sphero-stomatocytes. These invaginations were not found in electroporated/resealed RBCs. The intravenous administration of 51Cr-RBCs manifested a bimodal pharmacokinetic profile: an initial phase (t1/2alpha) with a rapid decrease of plasma 51Cr-RBCs followed by a slow and prolonged elimination phase (t1/2beta). The values corresponding to in vivo survival rate during the elimination phase indicated that the survival rate of 51Cr-electroporated loaded-RBCs was slightly lower (t1/2beta, 4.5 days) than 51Cr-native RBCs (t1/2beta, 5.3 days). The mean clearance values from blood of electroporated 51Cr-RBCs (unloaded and loaded) were higher (0.51 %51Cr/day and 0.54 %51Cr/day, respectively) than the obtained for native 51Cr-RBCs (0.18 %51Cr/day). The target organs for electroporated RBCs proved to be the same as for native RBCs. However, electroporated RBCs showed highest accumulation in liver, spleen and lung, since they were promptly recognized by the reticuloendothelium system. Mice induced to the state of acute ethanol intoxication and treated with ADH+ALDH-RBCs clearly showed a lower level of ethanol concentration in plasma (less than 43% ethanol) than the intoxicated mice treated with native RBCs. En consequence the clearance values of ethanol from blood in intoxicated mice treated with ADH+ALDH-RBCs (0.39 ml/min) were higher than the treated with native RBCs (0.20 ml/min). The results obtained suggest that ADH+ALDH-loaded erythrocytes could be used as a potential carrier system for in vivo removal of high levels of ethanol from blood caused by excessive alcohol consumption.
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PMID:Mouse erythrocytes as carriers for coencapsulated alcohol and aldehyde dehydrogenase obtained by electroporation in vivo survival rate in circulation, organ distribution and ethanol degradation. 1138 2

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

The kinetics of furfural inhibition of the enzymes alcohol dehydrogenase (ADH; EC 1.1.1.1), aldehyde dehydrogenase (AlDH; EC 1.2.1.5) and the pyruvate dehydrogenase (PDH) complex were studied in vitro. At a concentration of less than 2 mM furfural was found to decrease the activity of both PDH and AlDH by more than 90%, whereas the ADH activity decreased by less than 20% at the same concentration. Furfural inhibition of ADH and AlDH activities could be described well by a competitive inhibition model, whereas the inhibition of PDH was best described as non-competitive. The estimated K(m) value of AlDH for furfural was found to be about 5 microM, which was lower than that for acetaldehyde (10 microM). For ADH, however, the estimated K(m) value for furfural (1.2 mM) was higher than that for acetaldehyde (0.4 mM). The inhibition of the three enzymes by 5-hydroxymethylfurfural (HMF) was also measured. The inhibition caused by HMF of ADH was very similar to that caused by furfural. However, HMF did not inhibit either AlDH or PDH as severely as furfural. The inhibition effects on the three enzymes could well explain previously reported in vivo effects caused by furfural and HMF on the overall metabolism of Saccharomyces cerevisiae, suggesting a critical role of these enzymes in the observed inhibition.
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PMID:Inhibition effects of furfural on alcohol dehydrogenase, aldehyde dehydrogenase and pyruvate dehydrogenase. 1196 78

Pyruvate dehydrogenase, threonine aldolase and phosphoethanolamine lyase can produce acetaldehyde during normal metabolism. We studied the effect of loading with the substrates of these enzymes (pyruvate, 500 mg/kg, i.p., threonine 500 mg/kg, i.p., and phosphoethanolamine, 230 mg/kg, i.p.) on the blood concentrations of endogenous acetaldehyde and ethanol and the activities of enzymes producing and oxidizing acetaldehyde in the liver of normal rats and rats with liver injury provoked by chronic carbon tetrachloride (CCl4) treatment (0.2 ml i.p. per rat, 2 times a week during 4 weeks). Blood was collected before the treatment and then 30 min and 1 h following the administration of the substrates to intact and CCl4-treated rats. Endogenous acetaldehyde and ethanol were determined by headspace GC. The CCl4 treatment resulted in decreased liver alcohol dehydrogenase and aldehyde dehydrogenase activities and a significant elevation of liver endogenous ehtanol and a clear tendency to enhance blood acetaldehyde levels. Pyruvate increased blood endogenous acetaldehyde in CCl4-treated animals and endogenous ethanol--in the control group of animals. Threonine elevated endogenous acetaldehyde in normal rats. Phosphoethanolamine increased endogenous ethanol in the intact and CCl4 groups. At the same time, in CCl4-treated rats pyruvate administration increased the liver pyruvate dehydrogenase, threonine decreased threonine aldolase, whereas phosphoethanolamine decreased phosphoethanolamine lyase. Thus, the CCl4 effect on blood endogenous acetaldehyde and ethanol may be mediated through decreased liver ALDH and ADH activities. Liver injury promotes the accumulation of acetaldehyde, derived from physiological sources, including the degration of pyruvate and threonine by decreased acetaldehyde oxidation.
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PMID:[Effect of pyruvate, threonine, and phosphoethanolamine on acetaldehyde metabolism in rats with toxic liver injury]. 1224 86

Adult male and female rats were subjected to gonadectomy by means of surgical removal of the gonads. In the male, castration resulted in a significant decrease in both body and liver weights compared to intact controls, which persisted for at least 3 weeks. Conversely, ovariectomy was associated with a significant enhancement in both growth rate and liver weight from intact controls. Castration of male rats resulted in induction of hepatic L-ADH (cytosolic alcohol dehydrogenase) and L-ALDH (cytosolic aldehyde dehydrogenase) as contrasted with inhibition of mitochondrial ALDH which was evident in the enzyme with the apparent high Km. Kinetic studies indicate that there was an increase in apparent Km of L-ADH, and hence reduced affinity to hepatic metabolism of ethanol as a consequence of castration in the male rat. This is compared with few changes occurring in the apparent Km value of L-ALDH. Ovariectomy did not alter endogenous L-ADH or L-ALDH. Short-term administration of a synthetic estrogenic steroid ethinyl estradiol, inhibited liver mitochondrial ALDH in the intact female rat but not in the ovariectomized female. Short-term administration of the same dose of an androgen, testosterone, did not alter specific activities of the liver enzymes measured in the intact or in the castrated male rat. Administration of both components of OCs (oral contraceptives) combined or the estrogen alone in behavioral experiments profoundly reduced ethanol drinking by voluntary intake of diluted ethanol solution by the intact female rat. These results suggest a hepatic-gonadal link may exist and that a toxic interaction between the OCs and alcohol drinking is definitely possible.
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PMID:Studies on ethanol and oral contraceptives: feasibility of a hepatic-gonadal link. 1231 Sep 79

Alcohol dehydrogenase (ADH; EC. 1.1.1.1) and aldehyde dehydrogenase (ALDH; EC 1.2.1.3) play important roles in the metabolism of both endogenous and exogenous alcohols and aldehydes. The expression and localisation patterns of ADH (1-3) and ALDH (1-3) were investigated in the skin and liver of the mouse (BALB/c and CBA/ca), rat (F344) and guinea-pig (Dunkin-Hartley), using Western blot analysis and immunohistochemistry with class-specific antisera. ALDH2 expression and localisation was also determined in human skin, while ethanol oxidation, catalysed by ADH, was investigated in the mouse, guinea-pig and human skin cytosol. Western blot analysis revealed that ADH1, ADH3, ALDH1 and ALDH2 were expressed, constitutively, in the skin and liver of the mouse, rat and guinea-pig. ADH2 was not detected in the skin of any rodent species/strain, but was present in all rodent livers. ALDH3 was expressed, constitutively, in the skin of both strains of mouse and rat, but was not detected in guinea-pig skin and was absent in all livers. Immunohistochemistry showed similar patterns of expression for ADH and ALDH in both strains of mouse, rat, guinea-pig and human skin sections, with localisation predominantly in the epidermis, sebaceous glands and hair follicles. ADH activity (apparent V(max), nmoles/mg protein/min) was higher in liver (6.02-16.67) compared to skin (0.32-1.21) and lower in human skin (0.32-0.41) compared to mouse skin (1.07-1.21). The ADH inhibitor 4-methyl pyrazole (4-MP) reduced ethanol oxidation in the skin and liver in a concentration dependent manner: activity was reduced to approximately 30-40% and approximately 2-10% of the control activity, in the skin and liver, respectively, using 1 mM 4-MP. The class-specific expression of ADH and ALDH enzymes, in the skin and liver and their variation between species, may have toxicological significance, with respect to the metabolism of endogenous and xenobiotic alcohols and aldehydes.
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PMID:Species variations in cutaneous alcohol dehydrogenases and aldehyde dehydrogenases may impact on toxicological assessments of alcohols and aldehydes. 1249 13

Ethanol metabolism in the pancreas occurs predominantly by way of an nonoxidative pathway to fatty acid ethyl esters but oxidative routes to acetaldehyde also may contribute to injury of pancreatic cells. Three metabolic systems are responsible for the oxidative metabolism of ethanol, among which the cytochrome P-4502E1 and alcohol dehydrogenase have been found in the pancreas. The aims of this study were to detect ADH and ALDH in the human pancreas and to assess which ADH isoenzymes are present in this organ. ADH activity was measured by the photometric method and ADH isoenzyme activity was determined using sensitive and specific substrates. ALDH activity was measured by the fluorometric method. We have shown that the activities of ADH and ALDH are present in the pancreas, although the activity of ALDH was not proportionally as low as ADH activity. The class III isoenzyme exhibited the highest activity of all ADH isoenzymes tested and it was about 7 times higher than the activity of class I. The activities of classes II and IV were low. The activities of ADH isoenzymes of classes I, II, and III in the pancreas of men were significantly higher than in women. This study demonstrates that alcohol dehydrogenase and aldehyde dehydrogenase are present in the pancreas.
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PMID:Alcohol dehydrogenase (ADH) isoenzymes and aldehyde dehydrogenase (ALDH) activity in the human pancreas. 1287 Jul 77


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