Glutatião reduzido e oxidado da placenta na gravidez complicada com preeclâmpsia.

Abstract

Significative enhancement of free radical formation (FRO) in vivo is an important feature of hypertensive disorders of pregnancy (HDP), namely preeclampsia (PIH). The latest investigations about the pathology of HDP, showed the contribution of placental circulation to the development and evolution of such disease. The placental bed can be a potential source of FRO or activation of cells that can produce FRO. Glutathione, is an important molecule for cellular protection against damage, is a cofactor of many enzymes, in particular, for the glutathione peroxidase of the placental tissue; this enzyme in the placenta bed prevent the production of thromboxan and lipoperoxides; the latter are potentially damaging to the endothelium cells and can cause vasoconstriction, the most important feature of PIH. The activity of that enzyme is deficient in PIH. We studied, by fluorometric assay, the concentrations of the two states of glutathione in placental homogenates (PLH) from pregnant women without pathology (PWN) and from pregnant women with PIH (PWPIH). The data showed significant low concentrations in the PLH of the two states of glutathione in the PWN against high concentrations of this molecule in the PLH from PWPIH. This feature can result from a deficient user of the glutathione by the cellular mechanism for prevention against oxidative factors. In addition, our study shows a biochemical marker that is suggestive that the placental bed is a potential source of FRO production in PIH.