Xu Li, Liang Jun, Jin Tao, Zhou Feng
The Third Department of Orthopedics, the Second People's Hospital of Jinmen, Jinmen Hubei, 448000, P. R. China.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2016 Aug 8;30(8):1019-1025. doi: 10.7507/1002-1892.20160205.
To investigate the protective effect of mangiferin on acute spinal cord injury (SCI) in rats and its mechanism.
Ninety Sprague Dawley rats were randomly divided into 5 groups, 18 rats in each group. SCI was induced by using the Allen's method (60 g/cm) at T level in the rats of groups B, C, D, and E; laminectomy was performed at T in group A. The rats were injected intraperitoneally with saline in groups A and B, and with mangiferin in groups C (10 mg/kg), D (25 mg/kg), and E (50 mg/kg) every day for 30 days. The survival condition of rats was observed after operation; at 24, 48, and 72 hours after operation, the motor function of the hind limb was evaluated by the Basso, Beattie, Bresnahan (BBB) scores. The spinal cord edema was assessed by measuring the water content in spinal cord tissues at 72 hours. Meanwhile, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH) were detected by ELISA; nuclear factor κB (NF-κB), tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6 were measured via ELISA at the same time. Caspase-3 and Caspase-9 were also detected by ELISA after mangiferin treatment for 30 days. The expressions of Bax and Bcl-2 proteins were detected by Western blot. Pathological changes of the spinal cord was observed by HE staining. And Caspase-3 protein expression was detected by immunohistochemical staining.
All rats survived to the end of experiment. BBB scores of groups B, C, D, and E were significantly less than that of group A (<0.05), and it showed an increase trend from groups B to E (<0.05). The content of water of groups B, C, D, and E were significantly greater than that of group A (<0.05), and it showed a decrease trend from groups B to E (<0.05). ELISA showed that the activities of MDA, NF-κB, TNF-α, IL-1β, IL-6, Caspase-3, and Caspase-9 in groups B, C, D, and E were significantly greater than that in group A (<0.05), and they showed decrease trends from groups B to E (<0.05). Meanwhile, the activities of CAT, SOD, and GSH in groups B, C, D, and E were significantly less than that in group A (<0.05), and they showed increase trends from groups B to E (<0.05). Western blot showed that the relative expression of Bax protein in groups B, C, D, and E were significantly greater than that in group A (<0.05), and it showed a decrease trend from groups B to E (<0.05). Meanwhile, the relative expression of Bcl-2 protein in groups B, C, D, and E were significantly less than that in group A (<0.05), and it showed an increase trend from groups B to E (<0.05). Histological observation showed that the pathological changes in group B were accord with that in SCI, and the degree of necrosis in groups C, D, and E were significantly improved when compared with that in group B, and the effect was better in group E than group D, and group D than group C. Immunohistochemical staining showed that the absorbance (A) value of Caspase-3 in groups B, C, D, and E were significantly greater than that in group A (<0.05), and it showed a decrease trend from groups B to E (<0.05).
Mangiferin has neuroprotective effects on acute SCI in rats by alleviating edema of spinal cord, inhibiting oxidative stress and inflammation response, and regulating the Bcl-2 and Bax pathway.
探讨芒果苷对大鼠急性脊髓损伤（SCI）的保护作用及其机制。
将90只Sprague Dawley大鼠随机分为5组，每组18只。采用Allen法（60 g/cm）在B、C、D、E组大鼠的T节段诱导脊髓损伤；A组仅行T节段椎板切除术。A组和B组大鼠每天腹腔注射生理盐水，C组（10 mg/kg）、D组（25 mg/kg）和E组（50 mg/kg）大鼠每天腹腔注射芒果苷，连续30天。术后观察大鼠存活情况；术后24、48和72小时，采用Basso、Beattie、Bresnahan（BBB）评分评估后肢运动功能。术后72小时通过测量脊髓组织含水量评估脊髓水肿情况。同时，采用酶联免疫吸附测定（ELISA）法检测丙二醛（MDA）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH）；同时通过ELISA法检测核因子κB（NF-κB）、肿瘤坏死因子α（TNF-α）、白细胞介素1β（IL-1β）和IL-6。芒果苷治疗30天后，采用ELISA法检测Caspase-3和Caspase-9。采用蛋白质免疫印迹法检测Bax和Bcl-2蛋白的表达。通过苏木精-伊红（HE）染色观察脊髓的病理变化。采用免疫组织化学染色检测Caspase-3蛋白表达。
所有大鼠均存活至实验结束。B、C、D、E组的BBB评分均显著低于A组（P<0.05），且从B组到E组呈上升趋势（P<0.05）。B、C、D、E组的脊髓组织含水量均显著高于A组（P<0.05），且从B组到E组呈下降趋势（P<0.05）。ELISA结果显示，B、C、D、E组的MDA、NF-κB、TNF-α、IL-1β、IL-6、Caspase-3和Caspase-9活性均显著高于A组（P<0.05），且从B组到E组呈下降趋势（P<0.05）。同时，B、C、D、E组的CAT、SOD和GSH活性均显著低于A组（P<0.05），且从B组到E组呈上升趋势（P<0.05）。蛋白质免疫印迹法显示，B、C、D、E组的Bax蛋白相对表达量均显著高于A组（P<0.05），且从B组到E组呈下降趋势（P<0.05）。同时，B、C、D、E组的Bcl-2蛋白相对表达量均显著低于A组（P<0.05），且从B组到E组呈上升趋势（P<0.05）。组织学观察显示，B组的病理变化符合脊髓损伤表现，C、D、E组的坏死程度与B组相比均显著改善，且E组效果优于D组，D组优于C组。免疫组织化学染色显示，B、C、D、E组的Caspase-3吸光度（A）值均显著高于A组（P<0.05），且从B组到E组呈下降趋势（P<0.05）。
芒果苷可通过减轻脊髓水肿、抑制氧化应激和炎症反应以及调节Bcl-2和Bax通路，对大鼠急性脊髓损伤发挥神经保护作用。
