Anthocyanins are
flavonoids present in a variety of pigmented food and, like other
flavonoids, seem to play a role in preventing human pathologies related to oxidative stress. In fact,
anthocyanins have been shown to exert antiproliferative effects in cell cultures and exhibit antiinflammatory and vasoprotective activities in animal models. Although these
biological activities have been related to their
antioxidant properties, little is known on the molecular mechanism of action of
anthocyanins. The effects of pretreatment with the
anthocyanins delphinidin,
cyanidin, and their
glycoside and rutinoside derivatives against induction of DNA damage induced by
tert-butyl-hydroperoxide (TBHP) were evaluated in rat smooth muscle and in rat
hepatoma cell lines using alkaline single cell gel electrophoresis (Comet test). In addition, a possible protection exerted by
anthocyanins on cell killing, lipid peroxidation, and redox state alterations induced by TBHP was also investigated. It was found that the treatment with TBHP induces the formation of
DNA single strand breaks (SSB) and oxidised bases, along with cell killing, lipid peroxidation and redox state alteration. Our data demonstrate that
anthocyanins are effective against cytotoxicity,
DNA SSB formation and lipid peroxidation induced by TBHP, but they do not have any detectable effect against impairment by TBHP of cellular redox state and on protection against
DNA bases oxidation. The presence of a
sugar moiety in
anthocyanin derivatives reduced this protective effect, mainly in rat
hepatoma cells. The different activity of
anthocyanins and their derivatives may be explained taking into account a structure/function relationship that could also influence
anthocyanin intracellular localisation.