Effect of aronia on thiol levels in plasma of breast cancer patients

Abstract

AbstractThe various specific biomarkers of oxidative stress in plasma from patients with breast cancer, as well as biomarkers (the level of lipid hydroperoxides, conjugated dienes, thiobarbituric acid reactive substances) have been described. The aim of our present study was to evaluate the amount of low-molecular-weight thiols (which are physiological free radical scavengers) and establish the effects of the extract from A. melanocarpa on the amount of these thiols in plasma obtained from patients with invasive breast cancer, patients with benign breast diseases and from healthy volunteers. We observed in patients the higher amounts of homocysteine in plasma from patients in comparison to plasma from the control group; however the total level of glutathione, cysteine, cysteinylglycine, and the amount of thiols in reduced and oxidized forms was changed (e.g., in patients, the decrease of glutathione and cysteine reached about 50% of total values). Moreover, we showed that in the presence of the extract of A. melanocarpa (50 µg/mL, 5 min, 37°C), changes in amount of thiols in plasma from patients with invasive breast cancer and patients with benign breast diseases were significantly reduced in vitro. Considering the data presented in this study, we suggest that the extract from A. melanocarpa has an effect on thiol metabolism and the levels of all tested thiols observed in plasma obtained from breast cancer patients.