Fatty acids and other components of the diet may modulate, among others, mechanisms involved in homeostasis, aging, and age-related diseases. Using a proteomic approach, we have studied how
dietary oil affected
plasma proteins in young (6 months) or old (24 months) rats fed lifelong with two experimental diets enriched in either sunflower or virgin
olive oil. After the depletion of the most abundant
proteins, levels of less abundant
proteins were studied using two-dimensional electrophoresis and mass spectrometry. Our results showed that compared with the
sunflower oil diet, the virgin
olive oil diet induced significant decreases of plasma levels of
acute phase proteins such as
inter-alpha inhibitor H4P heavy chain (at 6 months),
hemopexin precursor (at 6 and 24 months), preprohaptoglobin precursor (at 6 and 24 months), and α-2-HS
glycoprotein (at 6 and 24 months);
antioxidant proteins such as type II
peroxiredoxin (at 24 months);
proteins related with coagulation such as
fibrinogen γ-chain precursor (at 24 months),
T-kininogen 1 precursor (at 6 and 24 months), and
apolipoprotein H (at 6 and 24 months); or with lipid metabolism and transport such as
apolipoprotein E (at 6 and 24 months) and
apolipoprotein A-IV (at 24 months). The same diet increased the levels of
apolipoprotein A-1 (at 6 and 24 months), diminishing in general the changes that occurred with age. Our unbiased analysis reinforces the beneficial role of a diet rich in virgin
olive oil compared with a diet rich in
sunflower oil, modulating
inflammation, homeostasis, oxidative stress, and cardiovascular risk during aging.