Protective effects of thymoquinone and alpha-tocopherol on the sciatic nerve and femoral muscle due to lower limb ischemia-reperfusion injury.

OBJECTIVE Thymoquinone (TQ) is an antioxidant and anti-apoptotic substance found in the Nigella sativa plant. Alpha-tocopherol (α-TP) is a potent antioxidant. We aimed to determine whether or not TQ and TP have a protective effect against lower limb ischemia-reperfusion (IR) injury of muscle and the sciatic nerve. MATERIALS AND METHODS A single dose of TQ 25 mg/kg was given intraperitoneally to the TQ group, a single dose of α-TP 200 mg/kg was given intraperitoneally to the α-TP group. IR was performed for 45 minutes after the drugs' applications. RESULTS While serum levels of malondialdehyde (MDA) and interleukin-6 (IL-6) of the IR group were significantly higher than those of the TQ plus α-TP, TQ and α-TP groups (p<0.001, p<0.001, p=0.008, respectively) and IL-6 (all p<0.001), the reduced glutathione (GSH) level of the IR group was lower than that of the other three groups. While neuronal nitric oxide synthase activity of nerve tissues of the IR group was significantly lower than that of the TQ plus α-TP group, the muscle tissue caspase-3 activity was higher than that of the TQ plus α-TP group. CONCLUSIONS Administration of TQ plus α-TP may strongly protect muscle and nerve tissues against IR injury via their synergistic effects.