Serotonin (5-HT) enhances the activity of amphotericin B against Aspergillus fumigatus in vitro.
We investigated the in vitro synergistic antifungal potential of combining serotonin (5-HT) and sertraline with amphotericin B and itraconazole against clinical isolates of Aspergillus spp. Synergy tests were performed using the chequerboard microdilution method. Activity was measured against Aspergillus fumigatus (n = 7), Aspergillus flavus (n = 3) and Aspergillus terreus (n = 2), and compared with that for Candida albicans and Candida parapsilosis. The fractional inhibitory concentration (FIC) indices ranged between 0.25 and 3 for the various isolates tested. 5-HT was shown to enhance the activity of amphotericin B against Aspergillus spp. Combination studies with 5-HT and itraconazole and with sertraline and itraconazole or amphothericin B showed different activities for the various strains, including synergism (FIC < 1.0), additivity (FIC = 1), and indifference (FIC between 1.0 and 2.0). 5-HT and sertraline showed antagonistic activity (FIC > 2) with amphotericin B and itraconazole against C. parapsilosis.
Heller
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I
Institute of Hygiene and Social Medicine, Leopold-Franzens University of Innsbruck, Fritz Pregl-Strasse 3/III, 6020 Innsbruck, Austria.
Leitner
S
S
Dierich
M P
MP
Lass-Flörl
C
C
D000666:Amphotericin B / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology; D001230:Aspergillus / Q000187:drug effects; D001232:Aspergillus fumigatus / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects; D004357:Drug Synergism; D008826:Microbial Sensitivity Tests; D012701:Serotonin / Q000494:pharmacology*
D000935:Antifungal Agents; D012701:Serotonin; D000666:Amphotericin B