Oxidative stress evaluation of skeletal muscle in ischemia–reperfusion injury using enhanced magnetic resonance imaging

Acute extremity arterial occlusion requires prompt revascularization. Delayed revascularization induces ischemia-reperfusion injury in the skeletal muscle. Organ injury-induced oxidative stress is widely reported, and oxidative stress is heavily involved in ischemia-reperfusion injury. This study aimed to evaluate oxidative stress in ischemia-reperfusion rat models using 3-carbamoyl PROXYL enhanced magnetic resonance imaging (3-CP enhanced MRI). Ischemia-reperfusion injury was induced through clamping the right femoral artery in rats, with a 4-h ischemia time in all experiments. 3-CP enhanced MRI was performed to evaluate oxidative stress, and the rats were divided into 3 reperfusion time groups: 0.5, 2, and 24 h. Signal intensity was evaluated using 3-CP enhanced MRI and compared in the ischemia-reperfusion and intact limbs in the same rat. Furthermore, the effect of edaravone (radical scavenger) was evaluated in the 4-h ischemia-24-h reperfusion injury rat model. The signal intensity of the ischemia-reperfusion limb was significantly stronger than that of the intact limb, suggesting that oxidative stress was induced in the ischemia-reperfusion muscle. Edaravone administration reduced the oxidative stress in the ischemia-reperfusion limb. The signal intensity of the ischemia-reperfusion limb was stronger than that of the intact limb, presumably reflecting the oxidative stress in the former. 3-CP MRI examination shows promise for effective assessment of oxidative stress and may facilitate early diagnosis of ischemia-reperfusion injury.