title: Effects of microcystins on human polymorphonuclear leukocytes.
abstract: Microcystins (MCs) are cyclic heptapeptides produced by cyanobacteria present in water contaminated reservoirs. Reported toxic effects for microcystins are liver injury and tumour promotion. In this study, we evaluated the effects of two MCs, MC-LR and [Asp(3)]-MC-LR, on human neutrophil (PMN). We observed that even at concentrations lower than that recommended by World Health Organization for chronic exposure (0.1 nM), MCs affect human PMN. Both MCs have chemotactic activity, induce the production of reactive oxygen species, and increase phagocytosis of Candida albicans. MC-LR also increased C. albicans killing. The effect of MCs on PMN provides support for a damage process mediated by PMN and oxidative stress, and may explain liver injury and tumour promotion associated to long-term MCs exposures.
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Brazil.
authors.forename: Paula
authors.initials: P
authors.lastname: Kujbida
authors.forename: Elaine
authors.initials: E
authors.lastname: Hatanaka
authors.forename: Ana
authors.initials: A
authors.lastname: Campa
authors.forename: Pio
authors.initials: P
authors.lastname: Colepicolo
authors.forename: Ernani
authors.initials: E
authors.lastname: Pinto
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D006801:Humans; D008387:Marine Toxins; D052998:Microcystins; D018375:Neutrophil Activation / Q000187:drug effects*; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D010456:Peptides, Cyclic / Q000008:administration & dosage*; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016897:Respiratory Burst / Q000187:drug effects / Q000502:physiology
chemical_list: D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D017382:Reactive Oxygen Species; C057862:cyanoginosin LR