Blood Concentration of Coenzyme Q10 Increases in Rats When Esterified Forms Are Administered

Abstract

Coenzyme Q levels decrease during aging in most tissues and in the target organs of a number of diseases. The uptake of this lipid into the blood and other tissues was investigated in 6-wk-old male Sprague-Dawley rats after 3 wk of dietary supplementation. In addition to the natural form of coenzyme Q10, acetylated and succinylated forms were also administered. Coenzyme Q10 was taken up into the blood, but uptake was significantly greater in rats given the succinylated (∼40%), and particularly, the acetylated forms (∼70%). All three forms increased significantly the total coenzyme Q concentration in both the liver (∼100%) and spleen (∼130%). Coenzyme Q10 and its esterified forms were not taken up into kidney, heart, muscle or brain. Intraportal and intraperitoneal administration of succinylated coenzyme Q10 gave results similar to those obtained in the dietary experiments. Uptake of the dietary coenzyme Q10 into the liver and spleen did not down-regulate the endogenous synthesis, i.e., the amounts of isolated coenzyme Q9 did not change in these tissues. Thus, esterification of coenzyme Q increases the uptake of dietary lipid into the blood; however, the derivatization does not contribute to the elevation of coenzyme Q levels in various organs.