Curcumin protects from cardiac reperfusion damage by attenuation of oxidant stress and mitochondrial dysfunction

This study was designed to investigate whether the pretreatment with curcumin, a yellow pigment from turmeric (Curcuma longa) known for its potent antioxidant capacity, was able to protect against the oxidant damage and mitochondrial dysfunction induced by reperfusion injury in isolated hearts. Rats were treated with a daily intragastric dose of curcumin (200 mg/kg) for 7 days prior to experimental ischemia (30 min) and reperfusion (60 min) (I/R). Cardiac mechanical work was measured during periods of stabilization, ischemia, and reperfusion. Oxidant stress and activity of antioxidant enzymes were measured in both homogenates of cardiac tissue and in isolated mitochondria. In addition, oxygen consumption was measured in isolated mitochondria. It was found that curcumin pretreatment attenuates the I/R injury as evidenced by (a) loss of cardiac mechanical work, (b) oxidant stress (increase in lipid peroxidation and decrease in reduced glutathione content) and (c) decrease in the activity of the antioxidant enzymes superoxide dismutase and glutathione reductase in both cardiac tissue and isolated mitochondria, and (d) decrease in mitochondrial respiratory capacity. In conclusion, the protective effect of curcumin was associated with the attenuation of oxidant stress and mitochondrial dysfunction secondary to I/R injury.