Effect Of Troxerutin On CCI-induced Neuropathic Pain And Inflammation In Lumber Spinal Cord

Object:To investigate the effect of troxerutin on treatment of neuropathic pain and expression changes of inflammatory factors in lumber spinal cord(L4-6) induced by CCI.Methods: A total of 60 health, adult Kunming mice weighting 25-35 g, were randomly divided into three groups: Sham group(n=20), CCI group(n=20), and Troxerutin group(n=20). Mice in Sham group were treated with sham surgery. Mice in CCI group and Troxerutin group were treated with CCI surgery. After surgery, mice in Troxerutin group were fed with troxerutin at a dosage of 150mg/kg/day. The baselines of paw withdrawal mechanical threshold(PWMT) and paw withdraw thermal latency(PWTL) in each groups were measured the day before surgery. After surgery, daily general behaviors such as diet, activity, gait, and activaties of licking paw in the first 3 days were record. Five mice in each group were used to measure the PWMT and PWTL changes following the surgeries. 4 mice of each group were deeply anesthetized and sacrificed in the third day after surgery and 11 mice were anesthetized and sacrificedin the seventh day. All the lumber spinal cord(L4-6) were taken after mice were sacrificed and the tissues were homogenated. Part of the supernatant was used to determine the levels of pro-inflammatory factor TNF-α expression in the third day(n=4), INF-γ and IL-1β in the seventh day(n=4) by ELISA. The supernatant’s NF-κB(p65) expression and phosphorylation of NF-κB(p65) were detected by western blot.Results: Phenomenons of licking paw were observed in CCI group and Troxerutin group. Compared to Sham groups, the values of PWMT and PWTL were significantly decreased after CCI surgery(P<0.05). And CCI surgery significantly increased the lumber expression of TNF-α in the third day, expression of NF-κB(p65), phosphorylation of NF-κB(p65) INF-γ and IL-1β in the seventh day in the lumber. Troxerutin did not decrease the percentage of mice with behavior of licking the operational paw(P>0.05). But troxerutin significantly inhibited the decrease of PWMT and PWTL values induced by CCI. Troxerutin also inhibited the lumber expression of TNF-α in the third day, and expression of NF-κB(p65), phosphorylation of NF-κB(p65), INF-γ, and IL-1β in the seventh day in the lumber.Conclusions: Troxerutin significantly improved CCI induced allodynia. The mechanism might be related to troxerutin’s ability of controlling the inflammation in the lumber.