Preservation of ischemic rat liver mitochondrial functions and liver viability with CoQ10.

The present study was undertaken to determine whether CoQ10 administration to rats can protect hepatic mitochondrial functions, improve energy metabolism during hepatic ischemia and subsequent reperfusion, and prolong the viability of the organ. Although ischemia of the liver for 90 minutes did not permit survival of the animals, CoQ10 administration (6 mg/kg of body weight) increased the survival rate to 60%. The period of ischemia was accompanied by decreases in hepatic adenosine triphosphate (ATP) level and respiratory control index without significant increases in mitochondrial calcium content and lipid peroxide formation. The subsequent restoration of blood flow resulted in a low recovery of ATP level, recovery of respiratory control and ADP:O ratio to levels significantly lower than normal, and on the contrary, marked increases in mitochondrial calcium and lipid peroxide levels. However, in CoQ10-treated animals mitochondrial functions were all completely reversible, and resynthesis of ATP was accelerated even after 90 minutes of ischemia. The pretreatment also completely suppressed the elevation of mitochondrial calcium and lipid peroxide levels. These results suggest that preservation with CoQ10 of cellular damages caused by hepatic ischemia is probably due to protection of cellular and subcellular membranes from lipid peroxidation, so that mitochondrial functions are restored and cellular calcium homeostasis is maintained.