Effects of subinhibitory concentrations of ketoconazole on in vitro adherence ofCandida albicans to vaginal epithelial cells

Abstract

The in vitro adherence of multiple 14C-glucose labeled isolates of Candida albicans to exfoliated vaginal epithelial cells in the presence of subinhibitory concentrations of ketoconazole was studied with a new method utilizing differential centrifugation in a gelatin-PBS solution as well as by the standard method of direct microscopy measurement. Pre-incubation of stationary-phase candida in ketoconazole at concentrations of 0.002 to 0.1 microgram/ml for 4 h at 37 degrees C had no effect on adherence. The addition of ketoconazole to logarithmic phase Candida albicans failed to reduce the total number of cell-associated adherent yeast but exposure to subinhibitory concentrations of ketoconazole was associated with a dystrophic morphology of the blastospores, extensive clumping and reduced germination resulting in fewer individual candida blastospores directly attached to the cell membranes. Germination inhibition and a marked reduction in adherent candida was observed when 0.01 microgram/ml ketoconazole was added to Candida albicans incubated in germination promoting medium. The diminished adherence of Candida albicans to vaginal epithelial cells after exposure to subinhibitory concentrations of ketoconazole may have clinical relevance in preventing recurrent candida vaginitis.

The effects of amphotericin B on the interaction of Candida albicans with fibroblast cultures

“…Although our results with respect to the inhibition of germ tube formation and elongation were consistent with observations reported by others for AmB (Nugent and Couchot 1986;Nugent et al 1987;Schaude et al 1987) and the imidazoles (Borgers et al 1979(Borgers et al , 1983Davies and Marriott 1981;Odds et al 1985;Shibl 1985;Sobel and Obedeanu 1983), correlating these events to subsequent reductions in the in vitro interaction of C. albicans with mammalian cells have not been previously reported. The results presented here also seem to indicate that while germ tube formation may be a prerequisite for fibroblast infection, modification of germinated cells by AmB may be sufficient to prevent yeast-fibroblast interactions.…”

In vitro inhibitory effect of Streblus asper leaf-extract on adhesion of Candida albicans to human buccal epithelial cells

“…Similarly, exposure to sub-inhibitory concentrations of garlic extract (Ghannoum, 1990), date extract (Abu-Elteen, 2000), octenidine and pirtenidine , amphotericin B and nystatin (Macura, 1988;Abu-el Teen et al, 1989) and ketoconazole (King et al, 1980;Sobel and Obedeanu, 1983) inhibited Candida germination and reduced attachment to human epithelial cells. Thus, the inhibition of germ tube formation by the SAE is important, since it is well known that germ tube and mycelial forms of Candida albicans adhere more efficiently to host cells than do yeast form cells (Kimura and Pearsall, 1980;Sobel et al, 1981;Hostetter, 1994;Pendrak and Klotz, 1995).…”

Oral Candidal Infections and Antimycotics

“…Though the mechanisms by which ketoconazole reduces mucosal colonization are not fully understood a marked reduction of germination and adhesion of C. albicans to vaginal and buccal epithelial cells following exposure to ketoconazole has been reported (Johnson et al, 1983;Sobel and Obedeanu, 1983;Macura, 1988;Vuddhakul et al, 1988;Abu-El Teen et al, 1989). In contrast, one group has reported that the adhesion of C. albicans to vaginal epithelial cells, in vitro, was not significantly altered when the drug was used to pre-treat the fungi or the vaginal cells or was added to the fungal/vaginal cell mixture (Odds and Webster, 1988).…”