title: Immune alterations in mice exposed to the herbicide simazine.
abstract: Simazine, a triazine herbicide, was investigated for its in vivo immunomodulatory properties. Male C57Bl/6 mice were treated with vehicle or 300 or 600 mg/kg body weight (bw) simazine daily orally for 4 wk. The immune system was evaluated by the antibody response to sheep red blood cells (SRBC; plaque assay and serum immunoglobulin G), natural killer (NK) and macro-phage activities, lymphocyte subpopulations in the spleen and thymus, and concanavalin A (Con A)- and lipopolysaccharide (LPS)-stimulated lymphocyte proliferation using splenocytes. Body weight and spleen and thymus weight decreased generally in simazine-treated mice, while the weight of adrenal glands was higher than in the control. Simazine treatment (600 mg/kg) induced an increase in the percentage of CD4(+) cells in spleen and CD8 + in thymus. Simazine inhibited the IgM plaque-forming cell numbers and lowered the level of IgG and the proliferation of mitogen-stimulated B cells and T cells. In addition, splenic NK and peritoneal macrophage activities in exposed mice were significantly decreased. Exposure to simazine also decreased cytokine production by macrophages, such as interleukin-1 (IL-1), IL-6, and tumor necrosis factor-alpha (TNF-alpha). Taken together, data indicate that the immune system was suppressed by oral simazine exposure.
authors.affiliation: Division of Immunopharmacology, College of Pharmacy, Sungkyunkwan University, Suwon, Kyunggi-do, South Korea.
authors.forename: Kyung-Ran
authors.initials: KR
authors.lastname: Kim
authors.forename: Eun-Wha
authors.initials: EW
authors.lastname: Son
authors.forename: Sung
authors.initials: S
authors.lastname: Hee-Um
authors.forename: Byung-Oh
authors.initials: BO
authors.lastname: Kim
authors.forename: Dong-Kwon
authors.initials: DK
authors.lastname: Rhee
authors.forename: Suhkneung
authors.initials: S
authors.lastname: Pyo
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006540:Herbicides / Q000008:administration & dosage / Q000633:toxicity*; D007107:Immune System / Q000187:drug effects*; D007694:Killer Cells, Natural / Q000187:drug effects; D008213:Lymphocyte Activation / Q000187:drug effects*; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009929:Organ Size / Q000187:drug effects; D012839:Simazine / Q000008:administration & dosage / Q000633:toxicity*; D013154:Spleen / Q000187:drug effects* / Q000276:immunology
chemical_list: D006540:Herbicides; D012839:Simazine