Reactive Nitrogen Species in Brain after In Vivo Exposure to Arsenic

Abstract

Arsenic (As) is a natural pollutant, which exposure is related to avariety of diseases like hypertension, diabetes, cancer andneurodegenerative or neurodevelopment impairment but, the exactmechanism by which As exposure could be toxic is still unclear.Studies employing different models of Astoxicity suggested that Ascould cause ROS generation and antioxidant depletion in biologicalsystems, including controversial data related to RNS generation andnitrosative damage. The hypothesis of the present work is that acute Asexposure could trigger an imbalance in the production of RNS in brain,leading to nitrosative stress and nitrosative-dependent cellular damage.The effect of in vivo exposure to As was studied by histopathology ofthe tissue, NO2- plus NO3- content, NO generation rate employingElectron Paramagnetic Resonance (EPR) techniques, and the content ofnitrotyrosine (NO2-Tyr) of total proteins in rat brain by western blottechniques. The data presented here suggested that the exposure to Asincreased the production of NO and lipid radicals in brain, leading tonitrosative damage to proteins and a depletion of the hippocampalpyramidal cell layer, that could affect functionality of the brain.