人第10染色体缺失性磷酸酶张力蛋白同源基因抑制剂SF1670对大鼠创伤性脑损伤的神经保护作用

Neuropective role of phosphatase and tensin homolog deleted on chromosome 10 inhibitor SF1670 in traumatic brain injury rats

目的探究人第10染色体缺失性磷酸酶张力蛋白同源基因(PTEN)抑制剂SF1670对大鼠创伤性脑损伤(TBI)的神经保护作用及其机制。方法采用Feeney’s自由落体硬膜外打击法制作大鼠创伤性脑损伤模型, 随机分为假手术组(Sham)、创伤性脑损伤+溶剂组(TBI+Vehicle)、创伤性脑损伤+SF1670组(TBI+SF1670)。药物实验组在术前2 h通过侧脑室注射SF1670(10 μmol/L, 2 μl), 在术后确定时间取脑组织样本。采用免疫荧光法、蛋白免疫印迹法、脑含水量测定、Fluoro-Jade C染色法和动物行为学测试来评价SF1670对大鼠创伤性脑外伤的神经保护作用。单因素方差分析进行组间比较。结果通过单因素方差分析可以发现相较于TBI+Vehicle处理组(91.41±1.20)%, TBI+SF1670组(82.90±0.96)%可以明显降低大脑含水量(n=6, F=300.896, P<0.05)。TBI+Vehicle处理下p-Akt/t-Akt最低(0.28±0.05), TBI+SF1670组(0.73±0.06)可以明显提高p-Akt/t-Akt(n=6, F=236.121, P<0.05)。TBI+Vehicle处理下FJC染色神经元数目最高[(309.18±17.20)个], TBI+SF1670组[(199.63±16.11)个]可以明显降低FJC染色神经元数目(n=6, F=612.806, P<0.05)。挂线测试第14天, TBI+SF1670组[4.50±0.47)分]与TBI+Vehicle组[(3.40±0.46)分]比较, n=6, SE=0.394, P<0.05;与TBI+IV+SF1670组[(3.18±0.52)分]比较, SE=0.762, P<0.05。脚缺陷测试第14天, TBI+SF1670组(0.10±0.04)与TBI+Vehicle组(0.21±0.04)比较, n=6, SE=0.077, P<0.05;与TBI+IV+SF1670组(0.24±0.04)比较, n=6, SE=0.082, P<0.05。圆柱体试验第14天, TBI+SF1670组(0.09±0.04)与TBI+Vehicle组(0.25±0.04)比较, n=6, SE=0.085, P<0.05;与TBI+IV+SF1670组(0.27±0.04)比较, n=6, SE=0.091, P<0.05。结论 PTEN抑制剂SF1670可通过上调磷酸化的Akt, 抑制损伤后神经元死亡, 对大鼠创伤性脑损伤发挥神经保护作用。

Objective To investigate the neuroprotective effect of SF1670 on traumatic brain injury(TBI)rats and its underlying mechanisms.Methods The TBI model was induced by Feeney’s weigh-drop method.The rats were randomly divided into sham group,TBI+vehicle group,TBI+SF1670 group.Rats were treated with SF1670(10μmol/L,2μL)2 h before TBI by i.c.v.The brain tissues were taken at the indicated time point.Immunofluorescence staining,Western blotting,brain water content,Fluoro-Jade C staining and behavior test were used for evaluating the neuroprotective effect of SF1670 on TBI.Data were expressed as mean±standard deviation,SPSS 17.0 was used for statistical analysis,and one-way analysis of variance(ANOVA)was used for inter-group comparison.Results The univariate ANOVA showed that as compared with TBI+vehicle treatment group[(91.41±1.20)%],brain water content was significantly reduced in TBI+SF1670 group[(82.90±0.96)%](n=6,F=300.896,P<0.05).The p-Akt/t-Akt was significantly reduced in TBI+vehicle group(0.28±0.05)as compared with that in TBI+SF1670 group(0.73±0.06)(n=6,F=236.121,P<0.05).The number of FJC-stained neurons in TBI+SF1670 group(199.63±16.11)was significantly reduced as compared with that in TBI+vehicle group(309.18±17.20)(n=6,F=612.806,P<0.05).On the 14th day of the online test,there was significant difference between TBI+vehicle group[(3.40±0.46)points]and TBI+SF1670 group[(4.50±0.47)points,n=6,SE=0.394,P<0.05)]or TBI+IV+SF1670 group[(3.18±0.52)points,SE=0.762,P<0.05].On the 14th day of foot defect test,there was significant difference between TBI+SF1670 group(0.10±0.04)and TBI+vehicle group(0.21±0.04,n=6,SE=0.077,P<0.05)or TBI+IV+SF1670 group(0.24±0.04,n=6,SE=0.082,P<0.05).On the 14th day of the cylinder test,there was significant difference between TBI+vehicle group(0.25±0.04)and TBI+SF1670 group(0.09±0.04,n=6,SE=0.085,P<0.05)or TBI+IV+SF1670 group(0.27±0.04,n=6,SE=0.091,P<0.05).Conclusion These results indicate that SF1670 can reduce neuroal death by increasing the level of p-Akt to confer neuropective effect in TBI rats.