Malassezin, a novel agonist of the aryl hydrocarbon receptor from the yeast Malassezia furfur, induces apoptosis in primary human melanocytes.
Pityriasis versicolor is the most common skin mycosis in humans worldwide. Yeasts of the genus Malassezia, particularly M. furfur, a saprophyte occurring widely on human skin, are generally regarded as the causative agents. Pityriasis versicolor is often accompanied by a long-lasting depigmentation that persists even after successful antimycotic therapy. M. furfur is able to convert tryptophan into a variety of indole alkaloids, some of them showing biological properties that correlate well with certain clinical features of pityriasis versicolor. This suggests a possible role for these compounds in the depigmentation process. We now report that human melanocytes undergo apoptosis when exposed to the crude mixture of tryptophan metabolites from M. furfur. The active compound was identified as malassezin, previously isolated by us from the same source and characterized as an agonist of the aryl hydrocarbon (Ah) receptor. The compound could, therefore, contribute to the marked depigmentation observed during the course of pityriasis versicolor.
Krämer
Hans-Joachim
HJ
Center of Andrology and Dermatology, Justus Liebig-Universität, Gaffkystrasse 14, 35385 Giessen, Germany. kraemer@innere.med.uni-giessen.de
Podobinska
Monika
M
Bartsch
Andrea
A
Battmann
Achim
A
Thoma
Wiebke
W
Bernd
August
A
Kummer
Wolfgang
W
Irlinger
Bernhard
B
Steglich
Wolfgang
W
Mayser
Peter
P
D017209:Apoptosis / Q000187:drug effects*; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D002855:Chromatography, Thin Layer; D020552:Comet Assay; D006801:Humans; D007211:Indoles / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008290:Malassezia / Q000737:chemistry*; D008544:Melanocytes / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D008854:Microscopy, Electron; D015394:Molecular Structure; D018336:Receptors, Aryl Hydrocarbon / Q000819:agonists* / Q000378:metabolism
D007211:Indoles; D018336:Receptors, Aryl Hydrocarbon; C436511:malassezin; D007770:L-Lactate Dehydrogenase; C506433:CASP9 protein, human; D053453:Caspase 9; D020169:Caspases