The effect of tobacco smoke on oxytocin concentrations and selected oxidative stress parameters in plasma during pregnancy and post-partum – an experimental model

Abstract

Background: Tobacco smoking is a serious threat to life and health of society. Among the most vulnerable to the toxic effects of tobacco smoke are foetuses and newborns. The objective of the research was to assess the impact of tobacco smoke exposure on oxytocin levels and biochemical oxidative stress parameters during pregnancy and after birth in an experimental model. Methods: In the experiment, exposure to tobacco smoke of gravid and non-gravid rats was monitored. A reliable biomarker of exposure – cotinine – was used in the process and it was determined by means of high-performance liquid chromatography with diode array detection, which ensured high analytical accuracy and precision. Determination of oxytocin was performed by means of enzyme-linked immunosorbent assay. The levels of selected oxidative stress parameters: total protein concentration, uric acid, trolox equivalent antioxidant capacity, protein S-nitrosylation and lipid peroxidation (thiobarbituric acid reactive substances) were measured by spectrophotometric methods. Results and conclusions: The effect of prenatal and postnatal exposure to tobacco smoke was a lower medium body mass of rat foetuses and pups. Oxidative stress during pregnancy, additionally intensified by tobacco smoke exposure, led to adaptive changes in properties of plasmatic antioxidant barriers. Moreover, the disturbance of oxidoreductive balance by tobacco smoke affects oxytocin fluctuations, what was observed in this study during lactation period. Therefore, women who smoke may breastfeed their children less frequently and for a shorter period.