phosphorus-radioisotopes and Candidiasis

To find novel drugs for effective antifungal therapy in candidiasis, we examined disulfiram, a drug used for the treatment of alcoholism, for its role as a potential modulator of Candida multidrug transporter Cdr1p. We show that disulfiram inhibits the oligomycin-sensitive ATPase activity of Cdr1p and 2.5mM dithiothreitol reverses this inhibition. Disulfiram inhibited the binding of photoaffinity analogs of both ATP ([alpha-(32)P]8-azidoATP; IC(50)=0.76 microM) and drug-substrates ([(3)H]azidopine and [(125)I]iodoarylazidoprazosin; IC(50) approximately 12 microM) to Cdr1p in a concentration-dependent manner, suggesting that it can interact with both ATP and substrate-binding site(s) of Cdr1p. Furthermore, a non-toxic concentration of disulfiram (1 microM) increased the sensitivity of Cdr1p expressing Saccharomyces cerevisiae cells to antifungal agents (fluconazole, miconazole, nystatin, and cycloheximide). Collectively these results demonstrate that disulfiram reverses Cdr1p-mediated drug resistance by interaction with both ATP and substrate-binding sites of the transporter and may be useful for antifungal therapy.

Topics: Adenosine Triphosphate; Azides; Candida albicans; Candidiasis; Cloning, Molecular; Disulfiram; Enzyme Inhibitors; Fungal Proteins; Genes, Reporter; Membrane Transport Proteins; Phosphorus Radioisotopes; Saccharomyces cerevisiae

White mice, Balb/c, were infected intraperitoneally with Candida albicans strains: standard ATCC 1023 and 910 strain isolated from vaginal excretions of patient suffering from genital mycosis. One group of animals was given new Polish polyene antibiotic N-methylglucamine salt of N-glucosylpolyfungin (N-MGP). It was possible to follow a course of infection using our own experimental model of candidiasis with 32P-Candida albicans cell suspension by measuring a degree of radioactivity of organs taken from treated and untreated animals. Statistically significant lower radioactivity values (P less than 0.01) were found in organs of animals treated with N-MGP salt for 20 days in daily dose of 20 mg/kg of body weight. Therapeutic efficacy of N-MGP salt was confirmed in separate experiments where mice were infected intraperitoneally with unlabelled Candida albicans cells. Negative results of mycological examinations were found when several organs homogenates of treated mice were tested. Activity of new polifungin derivative in chronic candidiasis of mice was found using two different ways of evaluation of this new preparation.

Topics: Animals; Antifungal Agents; Candida albicans; Candidiasis; Chronic Disease; Male; Mice; Mice, Inbred BALB C; Peritonitis; Phosphorus Radioisotopes; Polyenes

An attempt was made to produce DNA probes that could be used as a rapid and efficient means of detecting candidiasis (invasive Candida infection) in immunocompromised patients. Whole DNA from Candida albicans was digested with restriction endonuclease, and the resulting fragments were randomly cloned into a plasmid vector. Several recombinant plasmids were evaluated for cross-hybridization to various other Candida species, other fungal DNAs, and to nonfungal DNAs. Cross reactions were observed between the probes and different yeasts, but none with unrelated DNAs. Some recombinants were genus-specific, and two of these were applied to the analysis of C. albicans growth curves. It became evident that, although both 32P- and biotin-labelled probes could be made quite sensitive, a possible limitation in their diagnostic potential was the poor liberation of Candida DNA from cells. Thus, better methods of treatment of clinical specimens will be required before such probes will be useful in routine diagnosis.

Topics: Autoradiography; Candida albicans; Candidiasis; Cross Reactions; DNA Probes; DNA, Fungal; Phosphorus Radioisotopes