DNA breakage by resveratrol and Cu(II): reaction mechanism and bacteriophage inactivation.

Resveratrol (3,4',5-trihydroxy stilbene) is a phytoalexin and a polyphenolic compound present in human dietary material such as peanuts, mulberries, grapes and red wine. It is widely considered to possess cardiovascular protective properties and has also been shown to be chemopreventive against various stages of chemically induced carcinogenesis. It has recently been shown that resveratrol induces strand breakage in DNA in the presence of copper ions. In this paper, we have shown that resveratrol catalyzes the reduction of Cu(II) to Cu(I), which is accompanied by the formation of 'oxidized product(s)' of resveratrol, which in turn also appear to catalyze the reduction of Cu(II). Strand scission by the resveratrol-Cu(II) system was found to be biologically active as assayed by bacteriophage inactivation. The results are discussed in relation to the putative chemopreventive mechanism of resveratrol.