摘要
The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The main difference between the present three-stage hypothesis and other hypotheses is the assertion that, in the pathogenesis of early and late complicated pregnancy, methemoglobin takes on an important role. Methemoglobin by itself and from heme, redox-active ferric iron as a product of methemoglobin catabolism, has prooxidant properties and causes important structural and functional changes in the vascular endothelium, such as growth arrest, senescence, morphological alterations and cell apoptosis. Our own prospective study of methemoglobin in pregnancy revealed a significant rise and correlation between the ground level of SO2 and the level of methemoglobin: >1.5 g/L (r = 0.72, p 2, NOx, NO, NO2 and others) and that is an early biomarker of the identification of women with a pregnancy risk, and having an significant role upon adverse effects on mother and fetus health.
The tested hypothesis points out that exposure to environmental toxic substances originating from coal or other fossil fuels burning is the most decisive for the impacts of the metabolic synergy of nitrogen oxides as oxidants that cause hemoglobin oxidation to methemoglobin, and sulphur dioxide metabolites as inhibitors of antioxidants, in the bloodstream throughout the period of pregnancy. The main difference between the present three-stage hypothesis and other hypotheses is the assertion that, in the pathogenesis of early and late complicated pregnancy, methemoglobin takes on an important role. Methemoglobin by itself and from heme, redox-active ferric iron as a product of methemoglobin catabolism, has prooxidant properties and causes important structural and functional changes in the vascular endothelium, such as growth arrest, senescence, morphological alterations and cell apoptosis. Our own prospective study of methemoglobin in pregnancy revealed a significant rise and correlation between the ground level of SO2 and the level of methemoglobin: >1.5 g/L (r = 0.72, p 2, NOx, NO, NO2 and others) and that is an early biomarker of the identification of women with a pregnancy risk, and having an significant role upon adverse effects on mother and fetus health.
