Antifungal properties of 5-hydroxytryptamine (serotonin) against Candida species in vitro.
In this study the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of 5-hydroxytryptamine (5 HT, serotonin) against clinical isolates of Candida albicans (n = 11), Candida glabrata (n = 9), Candida tropicalis (n = 10) and Candida parapsilosis (ATCC 22019) using a broth microdilution test were investigated. In addition, it was examined whether delayed regrowth as a post-antifungal effect results following short exposure to 5 HT. 5 HT showed antifungal activity towards all isolates of Candida spp. The isolates yielded comparable MIC and MFC values of 5 HT in the range 0.91-7.34 mM and 1.83-14.68 mM, respectively. A lag in regrowth was dependent on the concentration tested. Treatment for 3 h at concentrations of 5 HT below and equipotent to the MFC resulted in a delayed regrowth of 8-12 h for isolates of Candida spp. In conclusion, these in vitro studies clearly demonstrate antifungal effects of 5 HT. Identifying the mode of action could be of great help in developing and researching new antifungal drugs.
Lass-Flörl
Cornelia
C
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
Fuchs
Dietmar
D
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
Ledochowski
Maximilian
M
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
Speth
Cornelia
C
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
Dierich
Manfred P
MP
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
Würzner
Reinhard
R
Institute of Hygiene and Social Medicine1 and Medical Chemistry and Biochemistry2, University of Innsbruck, Austria 3Department of Clinical Nutrition, University Hospital of Innsbruck, Austria.
D000935:Antifungal Agents / Q000494:pharmacology*; D002175:Candida / Q000187:drug effects* / Q000254:growth & development; D002176:Candida albicans / Q000187:drug effects / Q000254:growth & development; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers; D006801:Humans; D008826:Microbial Sensitivity Tests; D012701:Serotonin / Q000494:pharmacology*; D013997:Time Factors
D000935:Antifungal Agents; D016166:Free Radical Scavengers; D012701:Serotonin