Coenzyme Q10 depletion and mitochondrial energy disturbances in rejection development in patients after heart transplantation

Sixty endomyocardial biopsies (EMB) and whole blood or plasma samples from 34 patients after heart transplantation (HTx-pts) were studied. Acute rejection of the transplanted heart was histologically graded as: 0 (without), 0-1 (incipient), 1 (mild), 2 (moderate). The level of coenzyme Q(10) (CoQ(10)) in 28 EMB was estimated by HPLC. Mitochondrial respiratory chain function and energy production were measured in 60 EMB. This study is the first report showing a correlation between: (a) histological signs of rejection in the human transplanted heart and (b) CoQ(10) level of EMB, CoQ(10) blood level, and mitochondrial bioenergetic processes: inhibition in PAD-part, but not in NAD-part of respiratory chain. In all patients after heart transplantation (HTx-pts) the dynamic balance between total antioxidant status and degree of oxidative stress was disturbed. Conclusions: CoQ(10) level and mitochondrial bioenergetic functions of EMB contribute to the explanation of pathobiochemical mechanisms of origin and development rejection of human transplanted heart. We suppose that estimation of EMB CoQ(10) level could be used as a bioenergetic marker of rejection development in human transplanted heart. CoQ(10) therapy could contribute to the prevention of rejection of the transplanted heart.