丁苯酞对血管性痴呆大鼠Shh/Ptch1通路的影响

The effect of NBP on Shh/Ptch1 pathway in rats with vascular dementia

目的:观察血管性痴呆大鼠海马组织Shh,Ptch1,Smo和Gli1信号通路的变化,及不同剂量丁苯酞(NBP)对海马组织中Shh,Ptch1,Smo和Gli1表达的影响。方法:将SD大鼠分为模型组和不同剂量(30,60和120 mg·kg^-1)丁苯酞干预组。采用Western blot法和RT-PCR法进行检测Shh,Ptch1,Smo和Gli1蛋白或基因的表达情况。结果:Morris水迷宫实验定位航行实验:给予不同剂量的丁苯酞后,大鼠的逃避潜伏期均逐渐缩短,尤其以NBP120组更显著;HE染色:给予不同剂量的NBP后,SD大鼠海马区锥体神经元丢失明显减少,细胞形态较饱满,排列较为紧密,层次较清晰,尤其以NBP120组更显著;给予不同剂量的NBP后,各治疗组SYN,GAP43和PSD95在蛋白水平上表达上调(P<0.01)。NBP120组对SYN和PSD95蛋白表达的影响存在显著差异;同时各治疗组间PSD95的表达存在显著差异(P<0.01);Western blot方法检测发现,所有治疗组Shh,Ptch1,Smo和Gli1各蛋白的表达均显著上调(P<0.01);尤其是NBP120组对各蛋白的上调作用更加显著(P<0.05)。RT-PCR结果发现,NBP60组和NBP120组对Shh和Gli1指标的mRNA水平的表达作用无统计学差异;而对Ptch1和Smo的mRNA表达各治疗组间有统计学差异(P>0.05)。结论:VD大鼠海马组织细胞内Shh/Ptch1通路各指标表达下调,表明该通路参与了VD的发展过程;给予不同剂量的NBP后该通路被不同程度激活,促进海马神经元的存活,促进突触的形成并调节其可塑性,进而改善认知功能,起到神经保护作用。丁苯酞可能通过激活Shh/Ptch1信号通路而发挥神经保护作用,具体机制需进一步研究。

Objective:To observe the changes of Shh,Ptch1,Smo and Gli1 in hippocampus of rats with vascular dementia,and to explore the effect of NBP at different doses on the expression of those markers.Methods:SD rats were divided into model group and different dose group of NBP(30,60 and 120 mg·kg^-1).Protein and gene expression levels of Shh,Ptch1,Smo and Gli1 were assayed using Western blot and Real Time-PCR.Results:In the Morris water maze,after administering of different doses of NBP,the escape latency of different NBP-treated groups was significantly reduced with the NBP120 gould most significant.In HE staining,after treatment of NBP,especially 120 mg per day,reversed the morphologic changes were observed.After treatment with NBP at different doses,the expressions of the three markers,SYN,GAP43 and PSD95,significantly up-regulated compared to Model group(P<0.01).At the protein level,the expression of SYN and PSD95 exhibited the most significance in the NBP120 group(P<0.01).The expression of PSD95 exhibited the significance in the each treatment time group(P<0.01).In Western blot results,at the protein level,all treated groups were significantly up-regulated the expressions of the four markers than Model group(P<0.01),with the NBP120 group most significant.While at mRNA level,the treatment of NBP60 and NBP120 groups had nearly the same effect on the expression of Shh and Gli1.Although all treated groups had protective effects on the expression of Ptch1 and Smo.Conclusion:The expression of Shh/Ptch1 pathway in hippocampal neurons of VD rats decreased after BCCAO,indicating that the pathway was involved in the development of VD.After NBP was given,the pathway is activated to different extent to promote the survival of hippocampal neurons by promoting synaptic formation and regulating its plasticity.The activation of the pathway plays a neuroprotective role and improves cognitive function of VD.NBP plays a neuroprotective role by activating the Shh/Ptch1 signaling pathway,the specific mechanisms of which still need further studies.