Modifications of plasma proteome in long-lived rats fed on a coenzyme Q10-supplemented diet

Dietary coenzyme Q10 prolongs life span of rats fed on a PUFAn-6-enriched diet. Our aim was to analyze changes in the levels of plasma proteins of rats fed on a PUFAn-6 plus coenzyme Q10-based diet. This approach could give novel insights into the mechanisms of life span extension by dietary coenzyme Q10 in the rat. Serum albumin, which decreases with aging in the rat, was significantly increased by coenzyme Q10 supplementation both at 6 and 24 months. After depletion of the most abundant proteins by affinity chromatography, levels of less abundant plasma proteins were also studied by using 2D-electrophoresis and MALDI-TOF mass fingerprinting analysis. Our results have shown that lifelong dietary supplementation with coenzyme Q10 induced significant decreases of plasma hemopexin, apolipoprotein H and inter-α-inhibitor H4P heavy chain (at both 6 and 24 months), preprohaptoglobin, fibrinogen γ-chain precursor, and fetuin-like protein (at 6 months), and α-1-antitrypsin precursor and type II peroxiredoxin (at 24 months). On the other hand, coenzyme Q10 supplementation resulted in significant increases of serine protease inhibitor 3, vitamin D-binding protein (at 6 months), and Apo A–I (at 24 months). Our results support a beneficial role of dietary coenzyme Q10 decreasing oxidative stress and cardiovascular risk, and modulating inflammation during aging.