ABSTRACT
For a long time the formation of free radicals and the development of oxidative stress in
living organisms have been considered as exclusively damaging factors, leading to various
pathophysiological events. This is not surprising because numerous studies showed that the
development of many diseases is associated with the overproduction of free radicals.
Although this fact cannot of course be an undeniable proof of the predominant role of free
radicals or oxidative stress in these pathologies, an excess in the formation of free radicals and
other reactive oxygen and nitrogen species pointed out at least a casual intervention of all
these reactive compounds in disease development. However, we now know that not only the
overproduction but also the insufficient formation of free radicals could also be a cause of
pathological disorders. Therefore, the main approach to the treatment and prevention of
pathologies associated or accompanied by free radical formation should be the regulation and
not simple suppression of their formation.
