Coenzyme Q10: blood levels and metabolic demand

Blood levels of CoQ10 were found to be lower in patients affected by hyperthyroidism and in athletes during a severe training period. In patients who had received a kidney transplant decreasing CoQ10 levels were found, during the first 30 min after transplant, in the blood leaving the newly transplanted organ. No decrease was detectable in patients who had received the kidney from a sibling. It may reasonably be hypothesized that the ischaemia/reperfusion damage is responsible for a certain degree of impoverishment of CoQ10, leading to a CoQ10 uptake from perfusing blood. A comparable trend was also evident in liver transplants. Low CoQ10 plasma levels may therefore reflect increased metabolic needs from various tissues, on the basis of increased overall metabolic rate and/or peroxidative damage.