The effects of chronic psychogenic stress on the expression of DNA
damage and cellular response to the damage were investigated. Using the
comet assay, basal DNA damage was found to be similar in lymphocytes of
both affected and non-affected Populations (n = 30 in both groups). The
induction of DNA damage in lymphocytes by external factors (H2O2 and
gamma-irradiation), was also investigated. In these Studies, cells were
treated with 50, 100 and 150 muM H2O2 for 5 minutes or with 0.8, 2.5 and
4.2 Gy gamma-rays. A significant difference was found between the
chronically stressed and the control populations, indicating the
enhanced sensitivity of the former population. Cells were also held for
2 hours after the treatment, allowing time for the cells to deal with
the induced DNA damage. Based on the level of residual DNA strand
breaks, cells from the stressed population had more breaks than the
controls. Gender does not alter these findings. In conclusion, our data
indicate that cells from the stressed population were more sensitive to
the induction of DNA damage and had higher level of residual damage.
Therefore, stress conditions may cause the affected individuals to be
susceptible to environmental mutagenic agents