AI Article Synopsis
- The study investigated the effects of three antifungal azole drugs (ketoconazole, itraconazole, fluconazole) on the growth and sterol composition of various Leishmania strains.
- Itraconazole was found to be the most effective drug, inhibiting growth and sterol biosynthesis more than ketoconazole and fluconazole, particularly in certain subspecies like L. donovani and L. braziliensis.
- The drugs significantly altered the normal sterol profile, reducing major endogenous sterols and replacing them with 14 alpha-methyl sterols and cholesterol, suggesting that while these changes impact membrane functions, traces of specific sterols may still be necessary for other metabolic activities.
Article Abstract
Promastigotes of 36 World Health Organization reference (and other) strains of 6 species and 10 subspecies of Leishmania were cultured in the presence of 3 antimycotic azole drugs (ketoconazole, itraconazole, fluconazole) and their population growth determined. A representative of each subspecies was also analyzed for its sterol composition. For all strains the order of azole drug activity with respect to both growth and sterol biosynthesis inhibition was itraconazole greater than or equal to ketoconazole greater than fluconazole. The inhibitory actions of the three azole drugs were greater on L. donovani and L. braziliensis subspecies and on L. mexicana amazonensis than on L. aethiopica, L. major, L. tropica and L. mexicana mexicana. The nature of the changes in sterol composition caused by the drugs was the same for all strains. The normal, major endogenous sterols of the promastigotes (5-dehydroepisterol and ergosterol) were reduced in amount to 1-2% of the total free sterols and were replaced by endogenous 14 alpha-methyl sterols and exogenous cholesterol. The changes occurred rapidly, were drug concentration dependent and coincided with growth inhibition. Six strains of those Leishmania species less sensitive to the azole drugs could be subcultured indefinitely at reduced growth rates in the presence of a ketoconazole concentration causing the same extraordinary alterations in sterol composition. This suggested that the bulk membrane functions of sterols in leishmanias can be served by 14 alpha-methyl sterols and cholesterol, albeit imperfectly, while traces of 14 alpha-desmethyl sterols are needed for uncharacterized metabolic functions.
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| http://dx.doi.org/10.1016/0166-6851(88)90166-1 | DOI Listing |
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From Médecins Sans Frontières (L.G., F.V.), Sorbonne Université, INSERM Unité 1135, Centre d'Immunologie et des Maladies Infectieuses (L.G.), Assistance Publique-Hôpitaux de Paris, Groupe Hospitalier Universitaire Sorbonne Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (L.G.), and Epicentre (M.G., E. Baudin), Paris, and Translational Research on HIV and Endemic and Emerging Infectious Diseases, Montpellier Université de Montpellier, Montpellier, Institut de Recherche pour le Développement, Montpellier, INSERM, Montpellier (M.B.) - all in France; Interactive Development and Research, Singapore (U.K.); McGill University, Epidemiology, Biostatistics, and Occupational Health, Montreal (U.K.); UCSF Center for Tuberculosis (G.E.V., P.N., P.P.J.P.) and the Division of HIV, Infectious Diseases, and Global Medicine (G.E.V.), University of California at San Francisco, San Francisco; the National Scientific Center of Phthisiopulmonology (A.A., E. Berikova) and the Center of Phthisiopulmonology of Almaty Health Department (A.K.), Almaty, and the City Center of Phthisiopulmonology, Astana (Z.D.) - all in Kazakhstan; Médecins Sans Frontières (C.B., I.M.), the Medical Research Council Clinical Trials Unit at University College London (I.M.), and St. George's University of London Institute for Infection and Immunity (S.W.) - all in London; MedStar Health Research Institute, Washington, DC (M.C.); Médecins Sans Frontières, Mumbai (V. Chavan), the Indian Council of Medical Research Headquarters-New Delhi, New Delhi (S. Panda), and the Indian Council of Medical Research-National AIDS Research Institute, Pune (S. Patil) - all in India; the Centre for Infectious Disease Epidemiology and Research (V. Cox) and the Department of Medicine (H. McIlleron), University of Cape Town, and the Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine (S.W.) - both in Cape Town, South Africa; the Institute of Tropical Medicine, Antwerp, Belgium (B. C. J.); Médecins Sans Frontières, Geneva (G.F., N.L.); Médecins Sans Frontières, Yerevan, Armenia (O.K.); the National Center for Tuberculosis and Lung Diseases, Tbilisi, Georgia (N.K.); Partners In Health (M.K.) and Jhpiego Lesotho (L.O.) - both in Maseru; Socios En Salud Sucursal Peru (L.L., S.M.-T., J.R., E.S.-G., D.E.V.-V.), Hospital Nacional Sergio E. Bernales, Centro de Investigacion en Enfermedades Neumologicas (E.S.-G.), Hospital Nacional Dos de Mayo (E.T.), Universidad Nacional Mayor de San Marcos (E.T.), and Hospital Nacional Hipólito Unanue (D.E.V.-V.) - all in Lima; Global Health and Social Medicine, Harvard Medical School (L.L., K.J.S., M.L.R., C.D.M.), Partners In Health (L.L., K.J.S., M.L.R., C.D.M.), the Division of Global Health Equity, Brigham and Women's Hospital (K.J.S., M.L.R., C.D.M.), the Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, (L.T.), and Harvard T.H. Chan School of Public Health (L.T.) - all in Boston; and the Indus Hospital and Health Network, Karachi, Pakistan (H. Mushtaque, N.S.).
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