Effect of pesticides on apoptosis biomarkers in various rat tisúes.

ASTIZ MARIANA; TACCONI DE ALANIZ MARÍA J.; MARRA CARLOS ALBERTO

Villa Carlos Paz, Córdoba.

Congreso; XLIV Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB).; 2008

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

We previously demonstrated that the administration (i.p. 1/50 to 1/250 LD50, three times a week for 5 weeks) of dimethoate, glyphosate and zineb to rats, alone or in combination, provokes oxidative stress in liver (L) and brain (B) tissues. Now, we investigated the status of the apoptotic cell death pathway under these conditions. Caspase-3 activity was apparently unaltered in L and in cerebral cortex or substantia nigra. However we found higher activities of milli- and micro-calpains in treated groups compared with controls in both B regions. This proteolytic activity increased with pesticide associations. The inner mitochondrial membrane integrity (MMI) was decreased in treated animals between 20 to 60% compared with control samples from L or B preparations; nevertheless there were no differences in the outer MMI. We also observed a decrease in mitochondrial cardiolipin (CL) content which is usually associated with cytochrome C release. An apoptotic DNA fragmentation pattern was also observed in L and in B regions. We concluded that relative low doses of pesticides were able to induce an oxidative stress condition which is potentially enough to induce cellular apoptosis. This scenario is aggravated by the administration of pesticide mixtures. Results could contribute to the understanding of the etiological role that pesticides should play in neurodegenerative human illnesses.