title: Effects of microcystin-LR on patterns of iNOS and cytokine mRNA expression in macrophages in vitro.
abstract: The presence of cyanobacterial toxins in drinking and recreational waters represent a potential health hazard to the public. Microcystin-LR (MC-LR) is the most commonly encountered toxin and is a potent cyclic heptapeptide hepatotoxin produced by cyanobacteria. In this study, the immunomodulation by MC-LR of BALB/c mice peritoneal macrophages was investigated in vitro on mRNA levels of induced nitric oxide synthase and multiple cytokines by reverse-transcription polymerase chain reaction (RT-PCR). Lavaged peritoneal macrophages were incubated for 6 h with lipopolysaccharide (LPS) at a concentration of 100 microg/L and MC-LR at doses of 1, 10, 100, and 1000 nmol/L. Total RNA was extracted from the incubated macrophages, and then the levels of mRNA for induced nitric oxide synthase (iNOS), IL-1beta, TNF-alpha, GM-CSF, and IFN-gamma were detected. The results showed that expression of mRNA for iNOS, IL-1beta, TNF-alpha, GM-CSF, and IFN-gamma decreased significantly compared to the positive control (LPS only). These results have led us to propose the need for the establishment of a survey of the immunotoxicity of microcystins.
authors.affiliation: Department of Biochemistry, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.forename: Pingping
authors.initials: P
authors.lastname: Shen
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.forename: Zichun
authors.initials: Z
authors.lastname: Hua
mesh_terms: D000818:Animals; D000458:Cyanobacteria / Q000737:chemistry; D016207:Cytokines / Q000096:biosynthesis*; D004791:Enzyme Inhibitors / Q000633:toxicity*; D007107:Immune System / Q000187:drug effects; D008264:Macrophages; D008297:Male; D008387:Marine Toxins; D051379:Mice; D008807:Mice, Inbred BALB C; D052998:Microcystins; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D010456:Peptides, Cyclic / Q000633:toxicity*; D010533:Peritoneal Lavage; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D016207:Cytokines; D004791:Enzyme Inhibitors; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D012333:RNA, Messenger; D019001:Nitric Oxide Synthase; D010749:Phosphoprotein Phosphatases; C057862:cyanoginosin LR