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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1985-10-9
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pubmed:abstractText |
Leishmania mexicana mexicana promastigotes grown with cholesterol, supplied in natural products as the free sterol and as cholesteryl esters, were exposed to [2-14C]mevalonate and to the antimycotic drug ketoconazole. Growth was inhibited and cholesterol and 14 alpha-methyl sterols accumulated in free and esterified forms (cholesterol much greater than 4 alpha,14 alpha-dimethylcholesta-8,24-dien-3 beta-ol much greater than 14 alpha-methylcholesta-8,24-dien-3 beta-ol congruent to 14 alpha-methylergosta-8,24(28)-dien-3 beta-ol much greater than 4 alpha,14 alpha-dimethylergosta-8,24(28)-dien-3 beta-ol; identified by capillary gas chromatography/mass spectrometry, and by 1H and 13C nuclear magnetic resonance spectrometry). The 14 alpha-methyl sterols were preferentially labelled with 14C. The cholesterol was unlabelled and substituted for a substantial fraction of the major product of sterol biosynthesis, ergosta-5,7, 24(28)-trien-3 beta-ol (5-dehydroepisterol), but did not replace it and did not offer remarkable protection against either growth inhibition or alteration of sterol biosynthesis. Promastigotes grown with [6-2H]cholesterol or [4-14C]cholesterol did not contain labelled forms of Leishmania sterols, or other sterols. The chromatographic and spectrometric sterol analyses and the isotopic tracer findings suggested that ketoconazole impaired the cytochrome P-450 dependent 14 alpha-demethylation of lanosterol, that cholesterol was neither biosynthesized nor metabolized, and that the physiological functions of 5-dehydroepisterol had sterol structural requirements not entirely met by cholesterol. In all these studies, L. mexicana mexicana demonstrated a sterol biochemistry remarkably similar to that of fungi. This recommends an increase in interest in antimycotic drugs as chemotherapeutic agents for leishmanial infections.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Cholesterol,
http://linkedlifedata.com/resource/pubmed/chemical/Cytochrome P-450 Enzyme System,
http://linkedlifedata.com/resource/pubmed/chemical/Ketoconazole,
http://linkedlifedata.com/resource/pubmed/chemical/Lanosterol,
http://linkedlifedata.com/resource/pubmed/chemical/Mevalonic Acid,
http://linkedlifedata.com/resource/pubmed/chemical/Sterols
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pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
0166-6851
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
15
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
257-79
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:4033689-Animals,
pubmed-meshheading:4033689-Cholesterol,
pubmed-meshheading:4033689-Chromatography, Gas,
pubmed-meshheading:4033689-Cytochrome P-450 Enzyme System,
pubmed-meshheading:4033689-Ketoconazole,
pubmed-meshheading:4033689-Lanosterol,
pubmed-meshheading:4033689-Leishmania,
pubmed-meshheading:4033689-Magnetic Resonance Spectroscopy,
pubmed-meshheading:4033689-Mass Spectrometry,
pubmed-meshheading:4033689-Mevalonic Acid,
pubmed-meshheading:4033689-Sterols
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pubmed:year |
1985
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pubmed:articleTitle |
Sterols of ketoconazole-inhibited Leishmania mexicana mexicana promastigotes.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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