Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.9.3.1 (cytochrome oxidase)
 8,822 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When mice were exposed to 1% 2-ethylhexanoic acid in the diet, cytosolic and microsomal epoxide hydrolase (EC 3.3.2.3) activities were increased maximally (2-2.5- and 0.5-1-fold, respectively) after 3 days. Immunochemical quantitation of these enzymes indicated that the process involved was a true induction in both cases. Maximal levels of peroxisome proliferation (as indicated by carnitine acetyltransferase activity) were obtained after 7 days of exposure. All three of these activities returned to control levels within 4 days after termination of the treatment. The liver somatic index was slightly increased after 4 days of administration of 1% 2-ethylhexanoic acid, but the protein contents of the "mitochondrial," microsomal, and cytosolic fractions were unaffected. The activity of peroxisomal palmitoyl-CoA beta-oxidation was increased 2-fold, whereas peroxisomal catalase activity was unaffected. Exposure to 2-ethylhexanoic acid also increased cytochrome oxidase activity, suggesting an effect on mitochondria. Other parameters of detoxication--i.e. total microsomal cytochrome P-450 content, cytosolic glutathione transferase activity toward 1-chloro-2,4-dinitrobenzene, and the "cytosolic" epoxide hydrolase activity localized in the "mitochondrial" fraction--were not affected by 4 days of treatment with 1% 2-ethylhexanoic acid.
 ...
PMID:Characterization of the induction of cytosolic and microsomal epoxide hydrolases by 2-ethylhexanoic acid in mouse liver. 288 46

We have found here that there are clear structural requirements for peroxisome proliferation (monitored as increases in carnitine acetyltransferase activity, cyanide-insensitive palmitoyl-CoA oxidation, catalase and increases in the protein designated PPA 80) in mouse liver. From the investigation of ten structural analogues of 2-ethylhexanoic acid, it could be concluded that the most effective proliferators all have an ethyl group as the substituent on carbon 2 of the main chain, which consists of six carbons. The further observation from this group of compounds that a charged group is required for effective proliferation leads us to speculate that such a group is involved in the molecular mechanism as well. Many, but not all, of the effective peroxisome proliferators in a second group of compounds contain a phenoxy group, often with a substituted alpha carbon. Interestingly, the 2,4-dichlorophenoxyacetic and 2,4,5-trichlorophenoxyacetic acids are both effective peroxisome proliferators, but the closely related p-chlorophenoxyacetic acid is inactive in this respect, indicating that the chlorine atom at position 2 must be essential to the process in these cases. The results presented here also indicate that the structural requirements for proliferation of mitochondria are similar to those for proliferation of peroxisomes. Certainly, the most effective peroxisome proliferators also cause large increases in 'mitochondrial' protein and cytochrome oxidase activity, i.e. there is an obvious qualitative correlation.
 ...
PMID:Examination of the structural requirements for proliferation of peroxisomes and mitochondria in mouse liver by hypolipidemic agents, with special emphasis on structural analogues of 2-ethylhexanoic acid. 302 4

The effects of dietary exposure to 0.125% (w/w) p-chlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid or 2,4,5-trichlorophenoxyacetic acid on the content of peroxisomes and levels of certain xenobiotic-metabolizing enzymes in mouse liver have been investigated. In agreement with the literature on rat liver 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid were found to cause extensive proliferation of peroxisomes (as judged by the total levels of "mitochondrial" protein, carnitine acetyltransferase, cyanide-insensitive palmitoyl-CoA oxidation and catalase) in mouse liver. On the other hand, exposure to p-chlorophenoxyacetic acid did not significantly affect any of these parameters. As with certain other peroxisome proliferators, 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid increased total cytochrome oxidase activity as well. In addition, dietary exposure to 2,4-dichlorophenoxyacetic acid and to 2,4,5-trichlorophenoxyacetic acid resulted in increases in the activities of cytosolic and microsomal epoxide hydrolases in mouse liver and generally less pronounced increases in the total cytosolic glutathione transferase activity and microsomal content of cytochrome P-450. In the case of cytochrome P-450, this process can be said to be a true induction (i.e. the amount of enzyme protein is increased), because the assay procedure for cytochrome P-450 measures holoenzyme amount. Immunoquantitation demonstrated that this was also the case for the changes in cytosolic epoxide hydrolase. The dramatic differences in proliferation of peroxisomes and induction of xenobiotic-metabolizing enzymes seen here with compounds differing relatively little in structure may indicate that a receptor mechanism of some kind is involved.
 ...
PMID:Induction of cytosolic and microsomal epoxide hydrolases and proliferation of peroxisomes and mitochondria in mouse liver after dietary exposure to p-chlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid. 303 97

The case of a female patient with cardio-encephalo-myopathy who died of her illness at one year of age, similarly to her three sisters, is reported. In autopsy samples, like muscle, heart, liver and cerebellum activities of several mitochondrial enzymes were determined. In the skeletal muscle serious decrease of carnitine acetyltransferase was observed (from the normal 4.8 U/g to 0.08 U/g wet weight), while in other tissues this activity was normal. In the muscle activities of several other mitochondrial enzymes were also decreased (cytochrome oxidase, NADH cytochrome C oxidoreductase, citrate synthase), while in other tissues there were no similar changes. Serious distortion was observed in the structure of the majority of mitochondria of muscle and heart by electronmicroscopy. The number of the Purkinje-cells in the cerebellum decreased, and the cells were shrunken, their axons were fragmented and disoriented. Also the structure of the mitochondria was abnormal in the Purkinje-cells, while it was normal in other areas of the cerebrum. In te tissues of the patient normal and deleted mitochondrial DNA coexisted as which could explain the genetic background of this disease at molecular level.
 ...
PMID:[Mitochondrial DNA deletion in hereditary cardio-encephalo-myopathy]. 759 86