Relationship of plasma coenzyme Q10 and vitamin E with oxidative stress in patients with coronary artery disease

Coronary artery disease (CAD) is the leading cause of death in Taiwan. Higher oxidative stress may contribute to the pathogenesis of CAD. Coenzyme Q10 and vitamin E are lipid-soluble vitamins known for their excellent antioxidant qualities. The purpose of this study was to investigate the relationship of coenzyme Q10 and vitamin E concentrations with oxidative stress in patients with CAD. Patients who were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery were assigned to the case group (n = 51). The control group (n = 102) consisted of healthy individuals with normal blood biochemical values. Plasma coenzyme Q10, vitamin E, and malondialdehyde (MDA) concentrations and antioxidant enzyme activities [catalase (CAT) and glutathione peroxidase (GPx)] were measured. Subjects in the case group had significantly lower values of plasma coenzyme Q10, vitamin E, and antioxidant enzyme activities than the control group. Plasma coenzyme Q10 and vitamin E levels were significantly correlated with the MDA level and antioxidant enzyme activities. Patients with CAD were exposed to a higher level of oxidative stress and lower levels of coenzyme Q10 and vitamin E. Further study is needed to examine the benefits of administering coenzyme Q10 or vitamin E to CAD patients, especially those with higher levels of oxidative stress.