Analysis of the interrelationship of indices of oxidative stress with cytogenetic indicators of genome instability in blood samples of Moscow residents

Abstract

Introduction. Both mutagens and non-mutagenic chemical compounds, that can create conditions for a long-term shift in the oxidative balance in the body, contribute to increase of cancer risk in polluted regions. The aim of the study. To assess the nature of relationships between indices of oxidant status and indicators of genome instability in micronuclear test using a sample of Moscow residents. Materials and methods. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) content were determined in blood lysates of sixty nine Moscow residents (men of working age, 44 [38;58] years old), as well as 8-OHdG plasma content. Indicators of genome instability were determined in cytokinesis-block micronucleus assay of blood lymphocytes. Results. The rate of PHA-stimulated lymphocyte proliferation was shown to depend on the ratio of GPx and SOD activities in blood lysates: GPx accelerates proliferation, SOD slows down, and the optimal marker is GPx/SOD (R=0.418; p=0.00035 for proliferation index). The effects observed coincide with those obtained earlier on stabilized lines of spontaneously dividing cells; the absence of CAT influence was established for the first time. The frequencies of nucleoplasmic bridges (NPM) in 2-nuclear, polynuclear, and dividing cells but not of micronuclei, “broken eggs” and protrusions were associated positively with CAT and GPx activities (additive effect with close values of partial correlation coefficients; z=16.4x+0.17y-5.38 at R=0.464; p=0.0004 for the proportion of dividing cells with NPM). Further research is needed to explain these findings. No relationship was found between the results of cytome analysis and integral markers of oxidative stress (MDA, 8-OHdG). Limitations. It is possible that modified patterns will be obtained in polluted regions. Conclusion. Parallel study of free radical and cytogenetic indicators with their relationship will contribute to the selection of optimal markers for human health monitoring in regions with elevated levels of radiation or pro-oxidant chemicals.