Tissue-Level Dynamics and Redox State of Coenzyme Q10 in Rats After Intravenous Injection of Ubiquinol

Abstract

The ability of i.v. injected ubiquinol to influence the concentration and redox state of CoQ10 (concentration ratio of ubiquinol to total CoQ10) in rat tissues was evaluated. The ubiquinol and total CoQ10 contents before and for 8 d after i.v. administration of an aqueous solution (1%) of solubilized ubiquinol drug substance at a dose of 30 mg/kg were determined using HPLC with electrochemical detection. It was demonstrated for the first time that i.v. administration of ubiquinol did not affect the redox state in myocardium and brain and gradually increased it in liver, regardless of CoQ10 concentration changes in the organs. The ubiquinol fraction of the total CoQ10 content in blood plasma was constant for a minimum of 2 d after administration and was the highest of all studied tissues. The redox state of CoQ10 in plasma and organs differed because ubiquinol was partially oxidized to the level of the organ endogenous redox equilibrium during the transfer.