DNA strand breaks and base modifications induced by cholesterol hydroperoxides

Cholesterol (Ch) can be oxidized by reactive oxygen species, forming oxidized products such as Ch hydroperoxides (ChOOH). These hydroperoxides can disseminate the peroxidative stress to other cell compartments. In this work, the ability of ChOOH to induce strand breaks and/or base modifications in a plasmid DNA model was evaluated. In addition, HPLC/MS/MS analyses were performed to investigate the formation of 8-oxo-7,8-dihydro-2`-deoxyguanosine (8-oxodGuo) after the incubation of 2`-deoxyguanosine (dGuo) with ChOOH and Cu(2+). In the presence of copper ions, ChOOH induced DNA strand breaks in time and concentration-dependent manners. Purine and pyrimidine base modifications were also observed, as assessed respectively by the treatment with Fpg and Endo III repair enzymes. The detection of 8-oxodGuo by HPLC/MS/MS is in agreement with the dGuo oxidation in plasmid DNA. ChOOH-derived DNA damage adds further support to the role of lipid peroxidation in inducing DNA modifications and mutation.

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

INCT de Processos Redox em Biomedicina-Redoxoma

INCT de Processos Redox em Biomedicina-Redoxoma

Universidade de São Paulo - Pro-reitoria de Pesquisa da USP

Universidade de São Paulo - Pro-Reitoria de Pesquisa-USP