The imbalance between the production of Reactive Oxygen Species (ROS) and their sequestration promotes the formation of so-called oxidative stress conditions which are considered crucial in the aging process and development of many human diseases. Glutathione plays an essential role in the antioxidative barricade against ROS. Its role in the detoxification process of xenobiotics and carcinogen is also known. However, there are no comparative studies on the antioxidant properties of both biological samples and glutathione as well as the change in these properties as a result of exposure to various stress factors.
This paper fills this gap comparing the antioxidant activity of serum and plasma samples of the known glutathione content with the activity of glutathione itself assessed by the different methods. In addition, it reveals a significant role of environmental xenobiotics in oxidative stress and differentiates the stress induced by different groups of drugs, among which the greatest one has been demonstrated for antiarrhythmic drugs and cytostatics. More importantly, it proves that human plasma is more resistant to stress factors and N-acetylcysteine clearly promotes the extension of antioxidant properties of both the plasma and serum samples. The latter conclusion is consistent with the implied preventive and/or supportive action of this drug against SARS-CoV-2.