Bulló, M., M.R. Nogués, P. López-Uriarte, J. Salas-Salvadó, M. Romeu, 2010. Effect of whole walnuts and walnut-skin extracts on oxidant status in mice. Nutrition. 26(7-8):823-8.
Objective: To evaluate the effect of the intake of whole walnuts and walnut fractions on the oxidant status in mice. Methods: Thirty-six C57BL/6J male mice were randomized to be fed one of three diets: 1) a standard diet (control group), 2) a standard diet with 10% of whole walnuts (walnut-diet group), or 3) a standard diet with 2% of walnut skins (walnut-skin-diet group) for 8 wk. The plasma antioxidant capacity was measured by oxygen radical-absorbance capacity and plasma ferric-reducing antioxidant potential. Conjugated diene formation and reduced glutathione levels were also analyzed. Results: We observed no changes in plasma oxidation capability between the walnut and walnut skin groups with the exception of conjugated dienes. Plasma total antioxidant capacity and the ratio between reduced and oxidized forms of glutathione were lower in the walnut and walnut skin groups than in the control group. Conclusion: The decrease in the antioxidant burden observed in enzymatic and non-enzymatic antioxidant systems after sustained consumption of a whole-walnut or a walnut-skin diet in mice may be related to the plasma oxidation capability being maintained in the groups consuming the walnut diets.