title: A role for melatonin in maintaining the pro- and anti-inflammatory balance by influencing leukocyte migration and apoptosis in carp.
abstract: Melatonin is responsible for the synchronization of many physiological processes, including the immune response. Here we focus on the expression of melatonin MT1 receptors in/on leukocytes, and on the effects of melatonin administration on the inflammatory processes of carp. For the first time, we showed that fish leukocytes express MT1 receptors, implicating direct responsiveness to melatonin stimulation. Moreover, both in vitro and in vivo, melatonin modulated the immune response. The most potent effects of melatonin concerned the regulation of leukocyte migration. Melatonin reduced chemotaxis of leukocytes towards CXC chemokines in vitro. In vivo, during zymosan induced peritonitis, i.p. administration of melatonin reduced the number of neutrophils. This correlated with a melatonin-induced decrease of gene expression of the CXCa chemokine. Moreover, melatonin induced a decrease of the respiratory burst in inflammatory leukocytes. Although these data do suggest a potent anti-inflammatory function for this hormone, melatonin-induced inhibition of leukocyte apoptosis clearly indicates towards a dual function. These results show that also in carp, melatonin performs a pleiotropic and extra-pineal function that is important in maintaining the delicate pro- and anti-inflammatory balance during infection. They furthermore demonstrate that neuroendocrine-immune interaction via melatonin is evolutionary conserved.
authors.affiliation: Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, PL30-387, Krakow, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Kepka
authors.affiliation: Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, PL30-387, Krakow, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Szwejser
authors.affiliation: Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, PL30-387, Krakow, Poland.
authors.forename: Lukasz
authors.initials: L
authors.lastname: Pijanowski
authors.affiliation: Cell Biology and Immunology Group, Dept of Animal Sciences, Wageningen University, P.O. Box 338, 6700 AH, Wageningen, The Netherlands.
authors.forename: B M Lidy
authors.initials: BM
authors.lastname: Verburg-van Kemenade
authors.affiliation: Department of Evolutionary Immunology, Institute of Zoology, Jagiellonian University, Gronostajowa 9, PL30-387, Krakow, Poland. Electronic address: magdalena.chadzinska@uj.edu.pl.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Chadzinska
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects* / Q000276:immunology; D002347:Carps / Q000276:immunology*; D019743:Chemokines, CXC / Q000096:biosynthesis / Q000276:immunology; D002633:Chemotaxis / Q000187:drug effects* / Q000276:immunology; D007249:Inflammation / Q000276:immunology; D053765:Interleukin-12 Subunit p35 / Q000096:biosynthesis; D007962:Leukocytes / Q000276:immunology*; D008550:Melatonin / Q000494:pharmacology*; D018375:Neutrophil Activation / Q000187:drug effects; D009504:Neutrophils / Q000276:immunology; D010538:Peritonitis / Q000139:chemically induced / Q000276:immunology; D044122:Receptor, Melatonin, MT1 / Q000096:biosynthesis*; D016897:Respiratory Burst / Q000187:drug effects / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D015054:Zymosan
chemical_list: D000893:Anti-Inflammatory Agents; D019743:Chemokines, CXC; D053765:Interleukin-12 Subunit p35; D044122:Receptor, Melatonin, MT1; D014409:Tumor Necrosis Factor-alpha; D015054:Zymosan; D008550:Melatonin
keywords: Apoptosis; Carp; Chemotaxis; Inflammation; Melatonin; Respiratory burst