Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:1.1.1.1 (alcohol dehydrogenase)
9,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because ethanol ingestion lowers delta-aminolevulinic acid dehydratase (ALAD) activity in liver and red cells, effects of ethanol and acetaldehyde on ALAD in rat liver cytosol were studied. When added to the assay mix, as little as 0.5 mmol/L acetaldehyde competitively inhibited ALAD even in the presence of dithiothreitol, a sulfhydryl reagent. ALAD activity also fell when undiluted cytosol was incubated at 37 degrees with as little as 0.25 mmol/L acetaldehyde for 8 hours before enzyme assay. Inactivation of ALAD by acetaldehyde was prevented by the metabolic inhibitor NaF but not by the aldehyde dehydrogenase inhibitor cyanamide. Incubation of undiluted cytosol with 20 mmol/L ethanol also decreased ALAD activity, but addition of ethanol to the assay mix had no effect. Ethanol-mediated inactivation of ALAD was reduced by inhibition of alcohol dehydrogenase with 4-methylpyrazole, but ALAD activity was not decreased by incubation of undiluted cytosol with acetate or sorbitol or by addition of acetate to the assay mix. The aldehydic B6 vitamers, pyridoxal and pyridoxal phosphate, also inhibited ALAD activity when added to the assay mix. However, these vitamers increased ALAD activity and decreased acetaldehyde-mediated inactivation of ALAD when incubated for 8 hours with undiluted cytosol. We conclude that (1) acetaldehyde decreases ALAD activity both by competitive inhibition with substrate and by inactivation of enzyme protein and that (2) inactivation of ALAD by acetaldehyde may require nonoxidative metabolism of acetaldehyde. The net pharmacologic effect of B6 vitamers on ALAD activity and on inactivation of ALAD by acetaldehyde remains to be determined.
...
PMID:delta-Aminolevulinic acid dehydratase in rat liver: studies on the effects of ethanol, acetaldehyde, and B6 vitamers. 239 40

Alcoholism is one of the most challenging current health problems in the Western countries with far-reaching medical, social, and economic consequences. There are a series of factors that interact in predisposing or protecting an individual against alcoholism and alcohol-related disorders. This article surveys the state of our knowledge concerning the biochemical and genetic variations in alcohol metabolism and their implications in alcohol sensitivity, alcohol drinking habits, and alcoholism in different racial/ethnic groups. The major pathway for the degradation of ethanol is its oxidation to hydrogen and acetaldehyde--to which many of the toxic effects of ethanol can be attributed. Variations in alcohol and acetaldehyde metabolism via genetically determined polymorphisms in alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) seem to play an important role in individual and racial differences in acute and chronic reactions to alcohol, alcohol drinking habits, as well as vulnerability to organ damage after chronic alcohol abuse. Alcohol sensitivity and associated discomfort symptoms accompanying alcohol ingestion may be determinental for the significantly low incidence of alcoholism among the Japanese, Chinese and other Orientals of Mongoloid origin. An abnormal ALDH isozyme has been found to be widely prevalent among individuals of the Mongoloid race and is mainly responsible for the acute sensitivity to alcohol commonly observed in this race. Persons sensitive to alcohol by virtue of their genetically controlled ALDH isozyme deficiency may be discouraged from drinking large amounts of alcohol in their daily life due to the initial adverse reaction experienced after drinking alcohol. Indeed, a significantly low incidence of the mitochondrial ALDH isozyme deficiency has been observed in alcoholics as compared to psychiatric patients, drug dependents and healthy controls in Japan. How far any variation in ADH and/or ALDH activity among individuals of Caucasian origin will have similar effects has yet to be studied.
...
PMID:[Genetically-induced variability of alcohol metabolism and its effect on drinking behavior and predisposition to alcoholism]. 240 60

Both aldehyde dehydrogenase (ALDH, EC 1.2.1.3) and the aldehyde dehydrogenase activity of alcohol dehydrogenase (ADH, EC 1.1.1.1) were found to coexist in Drosophila melanogaster larvae. The enzymes, however, showed different inhibition patterns with respect to pyrazole, cyanamide and disulphiram. ALDH-1 and ALDH-2 isoenzymes were detected in larvae by electrophoretic methods. Nonetheless, in tracer studies in vivo, more than 75% of the acetaldehyde converted to acetate by the ADH ethanol-degrading pathway appeared to be also catalysed by the ADH enzyme. The larval fat body probably was the major site of this pathway.
...
PMID:The metabolism of ethanol-derived acetaldehyde by alcohol dehydrogenase (EC 1.1.1.1) and aldehyde dehydrogenase (EC 1.2.1.3) in Drosophila melanogaster larvae. 249 14

Research into the causes of alcoholism is a relatively recent scientific endeavor. One area of study which could lead to better understanding of the disease is the possibility of a genetic predisposition to alcoholism. Recent work has demonstrated that people have varying complements of enzymes to metabolize alcohol. Current knowledge is examined about the influence of various ethanol metabolizing enzymes on alcohol consumption by Asians and members of other ethnic groups. The two principal enzymes involved in ethanol oxidative metabolism are alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). ADH is responsible for the metabolism of ethanol to acetaldehyde. ALDH catalyzes the conversion of acetaldehyde to acetate. The different isozymes account for the diversity of alcohol metabolism among individuals. An isozyme of ADH (beta 2 beta 2) is found more frequently in Asians than in whites, and an ALDH isozyme (ALDH2), although present in Asians, often is in an inactive form. The presence of an inactive form of ALDH2 is thought to be responsible for an increase in acetaldehyde levels in the body. Acetaldehyde is considered responsible for the facial flushing reaction often observed among Asians who have consumed alcohol. A dysphoric reaction to alcohol, producing uncomfortable sensations, is believed to be a response to deter further consumption. Although the presence of an inactive ALDH2 isozyme may serve as a deterrent to alcohol consumption, its presence does not fully explain the levels of alcohol consumption by those with the inactive isozyme. Other conditions, such as social pressure, and yet undetermined biological factors, may play a significant role in alcohol consumption.
...
PMID:Research on alcohol metabolism among Asians and its implications for understanding causes of alcoholism. 251 95

Polymorphonuclear leukocytes (PMNL) release superoxide anions formed by a membrane-bound NADPH oxidase induced by stimulations. Properties of the inducers and their antagonists indicate that Ca2+, GTP-binding protein (G-protein), phospholipase C and Ca2+, phospholipid-dependent protein kinase (C-kinase) are mainly associated with the stimulation of receptors. Low concentrations of ATP induce the oxidase accompanied by the increase in the intracellular Ca2+ due to the flux from the medium and the storage site. ATP-gamma-S, UTP and ITP are effective but mononucleotides, dinucleotides, GTP and CTP are not. Leukotriene B4 (LTB4) which acts as a chemotactic agent and the inducer of the NADPH oxidase is catabolized. It is hydroxylated by a specific cytochrome P450 and then oxidized to a carboxy derivative by a cytosolic alcohol dehydrogenase and a microsomal aldehyde dehydrogenase in PMNL. Active NADPH oxidase was obtained by incubating membrane and cytosolic components of resting PMNL in the presence of sodium dodecyl sulfate (SDS). Two cytosolic components were obtained by an affinity chromatography on 2',5'-ADP Sepharose. One component is active in the presence of GTP or GTP-gamma-S and the other component in the presence of another cytosolic fraction.
...
PMID:Metabolism of stimulated polymorphonuclear leukocytes. 254 77

Allelic differences at the alcohol dehydrogenase (ADH) and aldehyde dehydrogenase loci may have an important role in an individual's alcohol sensitivity. We have cloned and sequenced all nine exons of an ADH2(2) allele which codes for an 'atypical' ADH, ADH beta 2. Our sequence data shows that the histidine at residue 47 of ADH beta 2 is encoded by CAC. Surprisingly, no silent substitution was found between the coding regions of ADH2(1) [Duester, G., Smith, M., Bilanchone, V. & Hatfield, G. W. (1986) J. Biol. Chem. 261, 2027-2033.] and ADH2(2) alleles over the 1122 nucleotide sites.
...
PMID:The genes for human alcohol dehydrogenases beta 1 and beta 2 differ by only one nucleotide. 254 9

We have previously reported that cytochrome P-450LTB in the microsomes of human polymorphonuclear leukocytes (PMN) catalyzes three omega-oxidations of leukotriene B4 (LTB4), leading to the sequential formation of 20-OH-LTB4, 20-CHO-LTB4, and 20-COOH-LTB4 (Soberman, R.J., Sutyak, J.P., Okita, R.T., Wendelborn, D.F., Roberts, L.J., II, and Austen, K. F. (1988) J. Biol. Chem. 263, 7996-8002). The identification of the novel final intermediate, 20-CHO-LTB4, allowed direct analysis of its metabolism by PMN microsomes in the presence of adenine nucleotide cofactors. Microsomes in the presence of 100 microM NAD+ or 100 microM NADP+ converted 1.0 microM 20-CHO-LTB4 to 20-COOH-LTB4 with a Km of 2.4 +/- 0.8 microM (mean +/- S.E., n = 4) and a Vmax of 813.9 +/- 136.6 pmol.min-1.mg-1, for NAD+, as compared to 0.12 microM and 5.0 pmol.min-1.mg-1 (n = 2) for NADPH as a cofactor. The conversion of 1.0 microM of 20-CHO-LTB4 to 20-COOH-LTB4 in the presence of saturating concentrations (1.0 mM) of both NAD+ and NADP+ was not greater than the reaction in the presence of 1.0 mM of each cofactor separately, indicating that NAD+ and NADP+ were cofactors for the same enzyme. Antibody to cytochrome P-450 reductase did not inhibit the conversion of 20-CHO-LTB4 to 20-COOH-LTB4. When 1.0 microM 20-OH-LTB4 was added to microsomes in the presence of NADPH, approximately three-fourths of the product formed (63.7 +/- 5.1 pmol; mean +/- S.E., n = 3) was 20-CHO-LTB4 and approximately one-fourth (21.3 +/- 3.9 pmol; mean +/- S.E., n = 3) was 20-COOH-LTB4. In the presence of both NADPH and NAD+, only 20-COOH-LTB4 (85.5 +/- 9.9 pmol; mean +/- S.E., n = 3) was formed. PMN microsomes also contain an NADH-dependent aldehyde reductase which converts 20-CHO-LTB4 to 20-OH-LTB4, a member of the LTB4 family of molecules with biological activity. Based upon kinetic, cofactor and inhibition data, microsomal aldehyde dehydrogenase preferentially regulates the final and irreversible inactivation step in the LTB4 metabolic sequence.
...
PMID:Identification of an aldehyde dehydrogenase in the microsomes of human polymorphonuclear leukocytes that metabolizes 20-aldehyde leukotriene B4. 254 38

Following a selective breeding program of heterogeneous mice for more than 30 generations, SS ("short sleep") and LS ("long sleep") lines have been developed on the basis of their sleep times when challenged with a single intraperitoneal dose of ethanol. The aromatic hydrocarbon responsiveness (Ah) locus encodes the Ah receptor, which regulates the induction of certain drug-metabolizing enzymes by polycyclic aromatic compounds such as 3-methylcholanthrene and tetrachlorodibenzo-p-dioxin. The C57BL/6 inbred mouse strain (B6; Ahb/Ahb) has a high-affinity Ah receptor, while the DBA/2 inbred mouse strain (D2; Ahd/Ahd) has a low-affinity Ah receptor. We show here that the SS inbred mouse line exhibits markedly elevated hepatic levels of the high-affinity Ah receptor, while the LS outbred mouse line contains the low-affinity Ah receptor. Among progeny of (B6D2)F1 X D2 backcross, the b/d heterozygote (having the high-affinity Ah receptor) was found to be several times more resistant than the d/d homozygote to a single dose of intraperitoneal ethanol. The D2.B6-Ahb congenic line is also several times more resistant to intraperitoneal ethanol than the B6.D2-Ahb congenic line is also several times more resistant to intraperitoneal ethanol than B6.D2-Ahd congenic line. We found that the waking blood ethanol levels are the same in b/d and d/d mice, suggesting that the relative ethanol resistance in b/d mice cannot be explained on the basis of a difference in central nervous system sensitivity. There are no differences between SS and LS mice or between b/d and d/d mice with regard to (i) blood acetaldehyde levels after a single intraperitoneal dose of ethanol, or (ii) hepatic alcohol dehydrogenase activities. There is a difference in the rate of ethanol elimination: SS more rapid than LS; b/d more rapid than d/d. Although SS mice have lower hepatic aldehyde dehydrogenase activities (cytosolic, mitochondrial low-Km: and mitochondrial high-Km forms) than LS mice, b/d and d/d do not show this difference. These data suggest that a selected mouse breeding program, based on resistance to a single intraperitoneal dose of ethanol, selects concurrently for the hepatic high-affinity Ah receptor. This selective advantage cannot be explained on the basis of changes in alcohol dehydrogenase or aldehyde dehydrogenase activities and might provide insight into the nature of the endogenous ligand for the Ah receptor.
...
PMID:Selective mouse breeding for short ethanol sleep time has led to high levels of hepatic aromatic hydrocarbon (Ah) receptor. 255 26

The effect of carbidine on enzymes of ethanol and acetaldehyde oxidation, the rate of ethanol elimination and the parameters of ethanol consumption were studied during long-term alcoholic intoxication. Carbidine administration was shown to increase the activity of alcohol dehydrogenase of the liver tissue, to decrease the activity of aldehyde dehydrogenase with a low Km to acetaldehyde. Also, the rate of ethanol elimination and a relative amount of consumed ethanol increase at the expense of an increase of the volume of consumed liquid.
...
PMID:[Effect of carbidine on parameters of ethanol oxidation in experimental alcoholic intoxication]. 257 20

Previous studies from this laboratory have shown that alcohols inhibit the localization of nitrosonornicotine and urethane in tissues of the mouse. Subsequent studies demonstrated that this inhibition of the localization of urethane was apparently due to an almost total inhibition of the metabolism of that compound by ethanol. We now report that dimethyl sulfoxide (DMSO) also almost completely inhibits the localization of urethane metabolites in tissues of the mouse and maintains a high concentration of urethane in blood. Since metabolism is essentially the only route of elimination of urethane in the mouse, this indicates that DMSO inhibits the metabolism of urethane. These studies lend further support to the suggestion that urethane is metabolized by either an alcohol dehydrogenase, an aldehyde dehydrogenase, or an alcohol-preferring isozyme of cytochrome P-450. These results indicate that studies on the metabolism as well as the carcinogenic activity of urethane (and possibly other chemicals) also may be affected by concurrent administration of DMSO.
...
PMID:Inhibition of the metabolism of urethane in the mouse by dimethyl sulfoxide (DMSO). 257 88


<< Previous 1 2 3 4 5 6 7 8 9 10

---