title: Immunomodulatory Effects of the Mycosporine-Like Amino Acids Shinorine and Porphyra-334.
abstract: Mycosporine-like amino acids (MAAs) are secondary metabolites, produced by a large variety of microorganisms including algae, cyanobacteria, lichen and fungi. MAAs act as UV-absorbers and photo-protectants. MAAs are suggested to exert pharmaceutical relevant bioactivities in the human system. We particularly focused on their effect on defence and regulatory pathways that are active in inflamed environments. The MAAs shinorine and porphyra-334 were isolated and purified from the red algae Porphyra sp. using chromatographic methods. The effect of MAAs on central signaling cascades, such as transcription factor nuclear factor kappa b (NF-κB) activation, as well as tryptophan metabolism, was investigated in human myelomonocytic THP-1 and THP-1-Blue cells. Cells were exposed to the MAAs in the presence or absence of lipopolysaccharide (LPS). NF-κB activity and the activity of tryptophan degrading enzyme indoleamine 2,3-dioxygenase (IDO-1) were used as readout. Compounds were tested in the concentration range from 12.5 to 200 µg/mL. Both MAAs were able to induce NF-κB activity in unstimulated THP-1-Blue cells, whereby the increase was dose-dependent and more pronounced with shinorine treatment. While shinorine also slightly superinduced NF-κB in LPS-stimulated cells, porphyra-334 reduced NF-κB activity in this inflammatory background. Modulation of tryptophan metabolism was moderate, suppressive in stimulated cells with the lower treatment concentration of both MAAs and with the unstimulated cells upon porphyra-334 treatment. Inflammatory pathways are affected by MAAs, but despite the structural similarity, diverse effects were observed.
authors.affiliation: Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria. kathrin.becker@i-med.ac.at.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Becker
authors.affiliation: Institute of Pharmacy, Pharmacognosy, University of Innsbruck, Innsbruck 6020, Austria. anja.hartmann@uibk.ac.at.
authors.forename: Anja
authors.initials: A
authors.lastname: Hartmann
authors.affiliation: Institute of Pharmacy, Pharmacognosy, University of Innsbruck, Innsbruck 6020, Austria. markus.ganzera@uibk.ac.at.
authors.forename: Markus
authors.initials: M
authors.lastname: Ganzera
authors.affiliation: Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria. dietmar.fuchs@i-med.ac.at.
authors.forename: Dietmar
authors.initials: D
authors.lastname: Fuchs
authors.affiliation: Division of Medical Biochemistry, Biocenter, Medical University of Innsbruck, Innsbruck 6020, Austria. johanna.gostner@i-med.ac.at.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Gostner
mesh_terms: D000596:Amino Acids / Q000276:immunology / Q000494:pharmacology*; D045744:Cell Line, Tumor; D003512:Cyclohexanones / Q000276:immunology / Q000494:pharmacology*; D003514:Cyclohexylamines / Q000276:immunology / Q000494:pharmacology*; D005998:Glycine / Q000031:analogs & derivatives* / Q000276:immunology / Q000494:pharmacology; D006801:Humans; D007155:Immunologic Factors / Q000276:immunology / Q000494:pharmacology*; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D044664:Porphyra / Q000737:chemistry; D000461:Rhodophyta / Q000737:chemistry; D014364:Tryptophan / Q000378:metabolism
chemical_list: D000596:Amino Acids; D003512:Cyclohexanones; D003514:Cyclohexylamines; D007155:Immunologic Factors; D016328:NF-kappa B; C421025:porphyra-334; D014364:Tryptophan; C494891:shinorine; D005998:Glycine
keywords: indoleamine 2,3-dioxygenase; mycosporine-like amino acids; nuclear factor kappa B; porphyra-334; shinorine