MANF对神经细胞中tau蛋白过度磷酸化的抑制作用  

MANF inhibits tau hyperphosphorylation in cultured neuronal cells

作　　者：李静[1,2] 王涛[1,2] 沈玉君[2] 方圣云[1,2] 沈玉先[1,2] 

机构地区：[1]安徽医科大学基础医学院,安徽合肥230032 [2]安徽医科大学生物药物研究所,安徽合肥230032

出　　处：《中国药理学通报》2012年第8期1111-1115,共5页Chinese Pharmacological Bulletin

基　　金：国家自然科学基金资助项目(No 30772557;30870881)

摘　　要：目的观察MANF是否可以抑制冈田酸诱导的N2a细胞中tau蛋白的过度磷酸化,以了解MANF神经保护作用的机制。方法采用体外培养小鼠神经母瘤细胞株N2a,以冈田酸(okadaic aicd,OA)作为诱导剂诱导N2a细胞中tau蛋白过度磷酸化,在加入重组人MANF蛋白干预或转染MANF过表达质粒及siRNA后,用MTT法检测细胞增殖活性的变化,并用AT-8抗体检测tau蛋白ser202/Thr205位点的磷酸化水平变化。结果 N2a细胞在加入重组人MANF蛋白预处理4 h后加入OA诱导24 h后,经Western blot和MTT法检测发现,重组人MANF蛋白能明显抑制N2a细胞中tau蛋白的过度磷酸化,并可促进N2a细胞的增殖活性;在转染MANF过表达质粒后,N2a细胞中OA诱导的过度磷酸化tau蛋白减少,且细胞活性增加;与此相反,转染siRNA下调内源性的MANF的表达则能促进N2a细胞中的tau蛋白过度磷酸化,并抑制细胞活性。结论 MANF可以抑制神经细胞中tau蛋白过度磷酸化,这可能是其发挥神经保护作用的原因之一。Aim To investigate the suppressive effect of MANF on okadaic acid （OA）-induced tau hyper- phosphorylation in N2a cells. Methods Mouse neuroblastoma N2a cells were cultured, and okadaic acid （OA） was used to induce tau hyperphosphorylation in N2a cells. The cells were treated with recombinant human MANF protein before exposure of OA. Meanwhile, MANF cDNA or siRNA was transfected to the cells to confirm the protective effect of MANF. The phosphorylated tau was detected by using AT-8 anti- body, which recognized Ser202/Thr205 phosphorylation of tau. The cell viability was determined by MTT assay. Results Pretreatment with recombinant human MANF for 4 h before OA exposure for 24 h, the viabil- ity of N2a was increased and the cellular level of hyperphosphorylated tau was decreased. Similarly, MANF cDNA transfection inhibited OA-induced tau hyperphosphorylation and cell impairment in N2a cells, whereas MANF siRNA transfeetion had an opposite effect. Conclusion MANF can inhibit tau hyperphosphorylation in N2a cells, which may be associated with its protective effects on neuronal cells.

关 键 词：MANF TAU 冈田酸 阿尔采末病 神经保护 细胞活性 

分 类 号：R332[医药卫生—人体生理学] R329.24[医药卫生—基础医学]