[Effect of ubiquinone and other scavengers on alterations caused by oxidative stress]

In the development of several diseases the oxidative stress is a significant aetiological or important pathogenetic factor. Its significance has been proved in the pathogenesis of several diseases, among them in arteriosclerosis and reperfusion, in inflammation and immunological disorders, as well as in toxic alterations and in carcinogenesis. The increased incidence of malignant tumors may be attributed to smoking, intemperate alcohol abuse, as well as inappropriate nutrition. Inappropriate nutrition is thought to be responsible for the development of about 30-50% of malignancies. In this paper the authors review the processes of the development of free radicals based on oxygen and nitrogen. They discuss the modalities which are able to decrease the oxidative stress, like the low oxygen tension in the tissues, the enzymatic and antioxidant protections, and the different repair mechanisms. In details the roles of ubiquinone, with other name of coenzyme Q, as well as of the selenium are discussed in the antioxidant defence processes. As a conclusion they suppose that oxidative stress in the organism and the alterations caused by them can be decreased by adequate nutrition or nutriceuticals.