Pro- and anti-oxidant effects of polyunsaturated fatty acid supplementation in HepG2 cells.

PUFA are bioactive nutrients thought to be effective in the prevention of many chronic diseases. PUFA susceptibility to free radical oxidation represents the other side of the coin, and the role of PUFA as pro- or anti-oxidants is still an unanswered question. In this study we supplemented HepG2 cells with different PUFA, and observed different effects on cytotoxicity, oxidation and modulation of antioxidant defenses. These were not simply related to the length of carbon chain, or to the number and position of double bonds. ARA supply evidenced the induction of oxidative damage, while DHA supplemented cells appeared richer in antioxidant defenses. To our knowledge, our study is the first evidencing the different pro- or anti-oxidant effect of different fatty acids when supplemented to cells. Overall, this points out the importance of not generalizing dietary recommendations considering PUFA as one category, but to extend them to the individual fatty acids.