Protective effect of coenzyme Q10 against hypoxic cellular damage.

Abstract

Heart cells from mouse embryos were cultured in either 5% CO2 and 95% air or 5% CO2 and 95% N2. Single myocardial cells showed frequent irregular beating under both conditions. Using this experimental system, we studied the effect of coenzyme Q10 (CoQ10) on the cellular functions of myocardial cells. Under the hypoxic conditions, CoQ10 decreased the irregular beating frequency without changing the beating rate. CoQ10 increased the cardiac adenosine 3', 5'-cyclic monophosphate (cAMP) level under the normal conditions and tended to decrease cardiac cAMP level under the hypoxic conditions. After incubation of deuterium-labeled CoQ10 (CoQ10-d5), the presence and levels of endogenous CoQ9, CoQ10 and exogenous CoQ10 were determined. Endogenous CoQ9 and CoQ10 were found in the mitochondrial fraction. Exogenous CoQ10 was found in the plasma membrane, cytosol and mitochondrial fractions. These findings confirm the protective effect of CoQ10 in ischemic heart disease. The exogeneous CoQ10 may provide protection against ischemic cellular damage by modulating cell functions.