ANTIOXIDATIVE EFFECT OF DIETARY COENZYME Q(10) IN HUMAN BLOOD-PLASMA

The effect of an oral dose of 90 mg/day coenzyme Q(10) on the antioxid ative status in 22 healthy young subjects (9 men and 13 women) was inv estigated before and after induction of an oxidative stress by fish oi l supplementation. The levels of oxidised and reduced coenzyme Q(10), alpha-tocopherol, ascorbate, TBARS and the fatty acid composition of p hospholipids were determined in plasma. The total amount of plasma enz yme Q(10) increased significantly from 0.7+/-0.1 mu mol/l before suppl ementation to 1.7+/-0.3 mu mol/l before supplementation while the redo x status (reduced CoQ(10)/total CoQ(10)) remained constant, even durin g a follow-up fish oil supplementation. The level of TBARS decreased d uring the first 2 weeks of CoQ(10) ingestion while the content of alph a tocopherol increased in the second week and ascorbate did not change . The decrease of TBARS and the presence of the majority of the orally supplemented CoQ(10) in the reduced form in plasma seem to indicate a n antioxidative role of CoQ(10) in blood plasma.