SBNeC 2010
Resumo:B.035


Prêmio
B.035TOXIC EFFECTS OF 1,2-DIHIDROXIBENZENE (CATECHOL) IN CENTRAL NERVOUS SISTEM TUMOR CELLS
Autores:Rute Maria Ferreira Lima (UFBA - Universidade Federal da Bahia) ; Diêgo Madureira de Oliveira (UFBA - Universidade Federal da Bahia) ; Lizandra Moreira Góes (UFBA - Universidade Federal da Bahia) ; Maria Socorro Grangeiro (UFBA - Universidade Federal da Bahia) ; Ramon dos Santos El-bachá (UFBA - Universidade Federal da Bahia)

Resumo

INTRODUCTION: Benzene is used as a raw material for the manufacture of chemicals and various drugs. It is one of the most important environmental work contaminants. The1,2-dihydroxybenzene (catechol) is a metabolite of benzene that can cross the blood-brain barrier and oxidize. The oxidation of this metabolite may in turn generate reactive oxygen species (ROS) and also reactive quinones. The effects of exposure to benzene are well documented in studies of epidemiology and toxicology. However, knowledge about the mechanisms of toxicity of its metabolites in various biological systems, mainly in the central nervous system is scarce. AIM: the aim of the present study was to examine the toxic properties of catechol in central nervous system (CNS) cell cultures. METHODS: since the study using primary cultures of cells from CNS is not so easy, due to ethical reasons, a useful strategy is the use tumor cell lines. These lines have glial and neuronal origin from human and animal sources. In this work, toxic effects of catechol were characterized on human glioblastoma (GL-15), rat glioma (C6), murine neuroblastoma (N2a) and human neuroblastoma (SH-SY5Y) cells. Catechol was dissolved in 5 χ 10-4 Μ HCl (final concentration) and used at increasing concentrations to examine its cytotoxic effects in all cell lines. All the cell cultures were exposed to catechol for 72 hours. Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). A nonlinear regression was performed to fit concentration-response curves using GraphPad Prism Software. This calculation was used to determine the concentration of catechol that killed effectively 50% of cells (EC50). RESULTS: the results showed that catechol has dose-dependent cytotoxic effects that was more evident to glial cells than to neuronal cells. The EC50 were 252 μM and 227 μM to GL-15 and C6 cells respectively. The EC50 were 27 μM and 38 μM to SH-SY5Y and N2a neuronal cell lines, respectively. CONCLUSIONS: the neuronal cells are more sensitive to CAT-induced toxicity than the glial ones. The results also showed that these effects are similar in cells from human and animal sources. This experimental model can be used for studying the toxicity of many other compounds in the CNS. (Supported by FAPESB/ CNPq)


Palavras-chave:  catechol, central nervous system, gliobalstoma, neuroblastoma, toxicity