The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Arthur W. Bull - One of the best experts on this subject based on the ideXlab platform.
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Metabolism of oxidized linoleic acid: characterization of 13-hydroxyoctadecadienoic acid dehydrogenase activity from rat colonic tissue.
Biochimica et biophysica acta, 1991Co-Authors: Sonja M. Earles, Joel C. Bronstein, David L. Winner, Arthur W. BullAbstract:An oxidized derivative of linoleic acid, 13-hydroxyoctadecadienoic acid (13-HODE), is dehydrogenated by an NAD+ dependent dehydrogenase present in rat colon mucosa. The product of the reaction is the 2,4-dienone, 13-oxooctadecadienoic acid. Enzyme activity was determined by HPLC analysis of incubation mixtures as well as by measuring the increase in absorbance at 285 nm, which represents formation of the 2,4-dienone chromophore. Characteristics of the reaction with respect to protein concentration, time of incubation and substrate dependence were investigated. Several inhibitors of known dehydrogenases had no effect on the 13-HODE dehydrogenase. These include, ethanol, indomethacin, 6-methyl-17-Hydroxyprogesterone Acetate, 4-(diethylamino)-benzaldehyde, and aspirin. The enzyme was mildly inhibited by pyrazole, 4-methylpyrazole and ibuprofen. Disulfiram was found to be a potent inhibitor of enzyme activity with an IC50 of 200 microM. Inhibitor specificity, and other characteristics of the reaction suggest the enzyme is neither alcohol dehydrogenase, diol dehydrogenase, nor a prostaglandin dehydrogenase. It is possible this enzyme plays an important role in the response of the colonic mucosa to the mitogenic effect of oxidized fatty acids.
Sonja M. Earles - One of the best experts on this subject based on the ideXlab platform.
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Metabolism of oxidized linoleic acid: characterization of 13-hydroxyoctadecadienoic acid dehydrogenase activity from rat colonic tissue.
Biochimica et biophysica acta, 1991Co-Authors: Sonja M. Earles, Joel C. Bronstein, David L. Winner, Arthur W. BullAbstract:An oxidized derivative of linoleic acid, 13-hydroxyoctadecadienoic acid (13-HODE), is dehydrogenated by an NAD+ dependent dehydrogenase present in rat colon mucosa. The product of the reaction is the 2,4-dienone, 13-oxooctadecadienoic acid. Enzyme activity was determined by HPLC analysis of incubation mixtures as well as by measuring the increase in absorbance at 285 nm, which represents formation of the 2,4-dienone chromophore. Characteristics of the reaction with respect to protein concentration, time of incubation and substrate dependence were investigated. Several inhibitors of known dehydrogenases had no effect on the 13-HODE dehydrogenase. These include, ethanol, indomethacin, 6-methyl-17-Hydroxyprogesterone Acetate, 4-(diethylamino)-benzaldehyde, and aspirin. The enzyme was mildly inhibited by pyrazole, 4-methylpyrazole and ibuprofen. Disulfiram was found to be a potent inhibitor of enzyme activity with an IC50 of 200 microM. Inhibitor specificity, and other characteristics of the reaction suggest the enzyme is neither alcohol dehydrogenase, diol dehydrogenase, nor a prostaglandin dehydrogenase. It is possible this enzyme plays an important role in the response of the colonic mucosa to the mitogenic effect of oxidized fatty acids.
Joel C. Bronstein - One of the best experts on this subject based on the ideXlab platform.
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Metabolism of oxidized linoleic acid: characterization of 13-hydroxyoctadecadienoic acid dehydrogenase activity from rat colonic tissue.
Biochimica et biophysica acta, 1991Co-Authors: Sonja M. Earles, Joel C. Bronstein, David L. Winner, Arthur W. BullAbstract:An oxidized derivative of linoleic acid, 13-hydroxyoctadecadienoic acid (13-HODE), is dehydrogenated by an NAD+ dependent dehydrogenase present in rat colon mucosa. The product of the reaction is the 2,4-dienone, 13-oxooctadecadienoic acid. Enzyme activity was determined by HPLC analysis of incubation mixtures as well as by measuring the increase in absorbance at 285 nm, which represents formation of the 2,4-dienone chromophore. Characteristics of the reaction with respect to protein concentration, time of incubation and substrate dependence were investigated. Several inhibitors of known dehydrogenases had no effect on the 13-HODE dehydrogenase. These include, ethanol, indomethacin, 6-methyl-17-Hydroxyprogesterone Acetate, 4-(diethylamino)-benzaldehyde, and aspirin. The enzyme was mildly inhibited by pyrazole, 4-methylpyrazole and ibuprofen. Disulfiram was found to be a potent inhibitor of enzyme activity with an IC50 of 200 microM. Inhibitor specificity, and other characteristics of the reaction suggest the enzyme is neither alcohol dehydrogenase, diol dehydrogenase, nor a prostaglandin dehydrogenase. It is possible this enzyme plays an important role in the response of the colonic mucosa to the mitogenic effect of oxidized fatty acids.
David L. Winner - One of the best experts on this subject based on the ideXlab platform.
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Metabolism of oxidized linoleic acid: characterization of 13-hydroxyoctadecadienoic acid dehydrogenase activity from rat colonic tissue.
Biochimica et biophysica acta, 1991Co-Authors: Sonja M. Earles, Joel C. Bronstein, David L. Winner, Arthur W. BullAbstract:An oxidized derivative of linoleic acid, 13-hydroxyoctadecadienoic acid (13-HODE), is dehydrogenated by an NAD+ dependent dehydrogenase present in rat colon mucosa. The product of the reaction is the 2,4-dienone, 13-oxooctadecadienoic acid. Enzyme activity was determined by HPLC analysis of incubation mixtures as well as by measuring the increase in absorbance at 285 nm, which represents formation of the 2,4-dienone chromophore. Characteristics of the reaction with respect to protein concentration, time of incubation and substrate dependence were investigated. Several inhibitors of known dehydrogenases had no effect on the 13-HODE dehydrogenase. These include, ethanol, indomethacin, 6-methyl-17-Hydroxyprogesterone Acetate, 4-(diethylamino)-benzaldehyde, and aspirin. The enzyme was mildly inhibited by pyrazole, 4-methylpyrazole and ibuprofen. Disulfiram was found to be a potent inhibitor of enzyme activity with an IC50 of 200 microM. Inhibitor specificity, and other characteristics of the reaction suggest the enzyme is neither alcohol dehydrogenase, diol dehydrogenase, nor a prostaglandin dehydrogenase. It is possible this enzyme plays an important role in the response of the colonic mucosa to the mitogenic effect of oxidized fatty acids.
H. P. G. Schneider - One of the best experts on this subject based on the ideXlab platform.
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The Role of Antiandrogens in Peri- and Postmenopausal HRT
Medical Science Symposia Series, 2002Co-Authors: H. P. G. SchneiderAbstract:Progesterone is the only natural progestogen with significant biological function. However, it is not well absorbed unless administered in a micronized form, which has been unavailable until recent years. Addition of a hydroxyl group at C17 of progesterone results in a loss of progestational activity. Acetylation of the 17-hydroxyl group gives rise to 17-hydroxy-progesterone Acetate, which has some progestational activity. This compound offers an important starting point in the development of a number of synthetic progestogens. Elongation of the carboxyl side chain at C17 of 17-Hydroxyprogesterone Acetate gives rise to long-acting progestogens, when used parenterally; one such example is 17-Hydroxyprogesterone caproate. Various manipulations of the 17-Hydroxyprogesterone Acetate molecule, primarily at C6, have produced potent oral as well as parenteral progestogens (Figure 1). The addition of a methyl group at C6 of 17-Hydroxyprogesterone Acetate gives rise to medroxyprogesterone Acetate. Formation of a double-bond between C6 and C7 of this compound yields megestrol Acetate. If to the latter molecule a methyl group is substituted at C6 with a chloral group and attachment of a methylene group so that it is shared jointly by C1 and C2 gives rise to cyproterone Acetate (CPA).
