Quercetin ameliorates peripheral nerve ischemia–reperfusion injury through the NF-kappa B pathway

This study aimed to investigate the protective effect of quercetin against ischemia–reperfusion (IR) injury induced in the sciatic nerve of the rat. Quercetin (20 mg/kg) was given during ischemia just before reperfusion. Four groups of rats (Q+IR3, Q+IR7, Q+IR14, and Q+IR28) received 3, 7, 14, and 28 days of reperfusion, respectively, after the intraperitoneal injection of quercetin. After reperfusion, a behavioral test was performed and the sciatic functional index was calculated. Each sciatic nerve was stained to check for edema and ischemic fiber degeneration. Immunohistochemical staining was performed to detect TNF-alpha and NF-kappa B, and TUNEL staining was carried out to detect apoptosis. The Q+IR3, Q+IR7, and Q+IR14 groups showed significantly increased behavioral scores and ameliorated sciatic functional index values compared to IR-injured rats that received vehicle alone during ischemia and then the same period of reperfusion. The Q+IR3, Q+IR7, Q+IR14, and Q+IR28 groups presented significant ischemic fiber degeneration (IFD), TNF-alpha expression, and apoptosis as compared with the IR-injured and perfused rats that did not receive quercetin. The Q+IR3, Q+IR7, and Q+IR28 groups also exhibited significantly decreased NF-kappa B expression (p < 0.001, p = 0.001, p = 0.026) as compared with the IR-injured rats that were perfused but did not receive quercetin. These results imply that quercetin may be beneficial in the treatment of sciatic IR injury because of its antiapoptotic and antiinflammatory effects and its ability to decrease the expression of NF-kappa B.