proBDNF对培养的海马神经元存活的影响及其机制

Effect of precursor of brain-derived neurotrophic factor on hippocampal neuron survival and its mechanism

目的:初步探讨proBDNF(precursor of brain-derived neurotrophic factor)对海马神经元的可能作用及其机制。方法:采用体外培养胚鼠海马神经元,并给予proBDNF,preBDNF(propeptide of proBDNF)和抗proBDNF血清处理;30min,1h和48h后行尼氏染色,ELK-p(Ets domain protein),ErK2(extracellularsignal regulated kinase)和c-fos免疫细胞化学染色。结果:给予proBDNF处理后,可见培养细胞内ELK-p,ErK2和c-fos表达明显上调,部分细胞核深染;而用抗血清中和内源性proBDNF后,ELK-p、ErK2和c-fos均下调,且细胞出现肿胀、空泡样变化。preBDNF处理组细胞与正常对照组类似。结论:proBDNF可维持海马神经元的存活,其机制可能与激活ErK和ELK信号通路有关。

Objective To explore the effect of precursor of brain-derived neurotrophic factor （proBDNF） on cultured hippocampal neuron and its intracellular mechanism. Methods The hip-pocampal neurons were dissociated from E18 rats and cultured in neurobasal medium, and then the cells were treated with proBDNF, preBDNF （ propeptide of proBDNF ） and proBDNF antiserum, re-spectively. Thirty minutes, 1 hour or 48 hours later, the cells were stained with Nissl solution, and the immunocytochemistry methods of ELK-p （ Ets domain protein ） , ErK2 （ extracellular signal regula-ted kinase） and e-fos were performed. Results The expressions of ELK-p, ErK and e-fos were significantly upregulated in the cultured hippocampal neurons after they were treated with proBDNF protein,and the immuno-positive staining was also obvious in some nuclei. While the endogenous proBDNF was neutralized by proBDNF antiserum treatment, the expressions of ELK-p, ErK and c-fos were downregulated and many cells showed swelling and vasoculation. The immunoreactivity in preBD-NF treated cells was similar to that in normal cultured cells. Conclusion proBDNF plays an important role in sustaining the hippocampal neuron survival through upregulating the ELK and ErK pathways.