Toxicity and carcinogenicity mechanisms of fibrous antigorite.
We studied the effects of fibrous antigorite on mesothelial MeT-5A and monocyte-macrophage J774 cell lines to further understand cellular mechanisms induced by asbestos fibers leading to lung damage and cancer. Antigorite is a mineral with asbestiform properties, which tends to associate with chrysotile or tremolite, and frequently occurs as the predominant mineral in the veins of several serpentinite rocks found abundantly in the Western Alps. Particles containing antigorite are more abundant in the breathing air of this region than those typically found in urban ambient air. Exposure of MeT-5A and J774 cells to fibrous antigorite at concentrations of 5-100 microg/ml for 72 hr induced dose-dependent cytotoxicity. Antigorite also stimulated the ROS production, induced the generation of nitrite and PGE2. MeT-5A cells were more sensitive to antigorite than J774 cells. The results of this study revealed that the fibrous antigorite stimulates cyclooxygenase and formation of hydroxyl and nitric oxide radicals. These changes represent early cellular responses to antigorite fibers, which lead to a host of pathological and neoplastic conditions because free radicals and PGE2 play important roles as mediators of tumor pathogenesis. Understanding the mechanisms of the cellular responses to antigorite and other asbestos particles should be helpful in designing rational prevention and treatment approaches.
Cardile
Venera
V
Department of Physiological Sciences, University of Catania, Italy. cardile@unict.it
Lombardo
Laura
L
Belluso
Elena
E
Panico
Annamaria
A
Capella
Silvana
S
Balazy
Michael
M
D000818:Animals; D017632:Asbestos, Serpentine / Q000633:toxicity*; D015197:Carcinogenicity Tests; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D051379:Mice; D019016:Mineral Fibers / Q000633:toxicity; D009573:Nitrites / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects; D026361:Reactive Nitrogen Species / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism
D017632:Asbestos, Serpentine; D019016:Mineral Fibers; D009573:Nitrites; D026361:Reactive Nitrogen Species; D017382:Reactive Oxygen Species; D007770:L-Lactate Dehydrogenase; D015232:Dinoprostone