Glutathione status of placentae from differently polluted regions of Ukraine

A study of the glutathione status as a prerequisite of the detoxifying activity of the fetoplacental barrier was undertaken in different regions of the Ukraine that have been judged either 'clean', chemically polluted or radioactively contaminated with different summary effective equivalent annual expositional doses (SEEAED). In the samples from clean regions, cytosolic glutathione transferase (GST), glutathione reductase (GSSG-R) activities and contents of total SH-groups were higher than in contaminated areas and corresponded to 50.4 +/- 9.0. 13.6 +/- 1.8 mU/mg cytosolic protein and 30.2 +/- 5.7 mumol/g tissue, respectively. In heavily radioactively exposed women, e.g. 'liquidators' (SEEAED in 1986: > 5 mSv), low GST activity, 17.0 +/- 3.0 mU/mg cytosolic protein and high malonic dialdehyde concentration, 128.8 +/- 13 nmol/g tissue were found; the latter serves as a measure of lipid peroxidation. In the placental specimens from heavily exposed women, the distribution of GST pi-specific antigen along the villi was irregular and differed from specimens of unexposed women. Malonic dialdehyde concentrations in all other groups of women were in the range 37.1-69.2 nmol/g tissue. In less exposed women, e.g. Kiev citizens and those from some rural areas (SEEAED in 1986: 4.9 and < 1 mSv, respectively), GST activity, 19.1 +/- 2.1 and 33.7 +/- 5.0 mU/mg cytosolic protein, increased concomitantly with the total content of SH-groups, 7.4 +/- 1.0 and 15.3 +/- 1.6 mumol/g tissue, and with the decreasing values of the first year SEEAED. GST activity, 49.6 +/- 8.8 mU/mg cytosolic protein, and total SH-group content, 19.8 +/- 0.5 mumol/g tissue, were even higher in the women evacuated on the second day after the catastrophe. Placental GST activity in chemically exposed women. 18.0 +/- 2.0 mU/mg cytosolic protein, was in the range of the lowest obtained values but the differences in the placental glutathione status between radioactively contaminated and chemically polluted areas point to different pathogenetic mechanisms of this reduction. The inverse correlation between the mean values of GSSG-R activities and the concentration of low-molecular weight thiols appears to be true for all groups. The indices of the placental glutathione status seem to be sensitive to environmental pollution.