Assessing of the role superoxide, nitric oxide and redox metals in cytotoxic effect of the Н₂О₂ and amyloid-β-protein

Abstract

On the cells of neuroendocrine tumor of rats (line PC12) in culture was estimating of the governing mechanisms of the cytotoxicity of the oxidative stress and the role of the amyloids in increasing this stress. Using flowcytometric assessment of the cytotoxicity Н₂О₂ and fragment b-amyloid (Αβ) peptide (25-35) has been shown the dose-dependent increasing of the quote of the cells with DNA content <2c. Isoeffective consentrations were 1 мМ Н₂О₂ and 5 мкМ Αβ. The cytotoxicity Н₂О₂ and Ab were accompanig with the increasing of the intracellular level of O₂^-. The treatment of the cells GSNO (donor of NO) and o-phenantrolin (chelators of Fe ions) significantly decreased the intracellular level of O₂^- as well as the cytotoxicity Н₂О₂ and Αβ. Thus, in direct experiments has been shown of the part amyloids in the increasing of the oxidative stress and participation of the reactive oxide radicals in the cytotoxic effect of the Αβ. The addition argument which confirmed contribution of the oxidative stress in the cytotoxic effect of the Αβ was the similarity of the cellular response on the action of the oxidative agent — Н₂О₂ and Αβ.