糖尿病大鼠神经干细胞视网膜下移植后TLR4、NF-κB的表达

Expression of TLR4 and NF-κB in streptozotocin-induced diabetic rats following transplantation of NSCs into subretinal space

目的观察糖尿病大鼠视网膜下移植大鼠胚胎神经干细胞(NSCs)后转录因子(NF-κB)、Toll样受体4(TLR4)的表达。方法大鼠糖尿病成模后,A组视网膜下移植大鼠NSCs,B组视网膜下填充DMEM,C组不做手术处理。NSCs移植组术后1、2、4周分别取双眼颞上视网膜做对照检测。Western blot法检测TLR4和NF-κB的蛋白表达。结果A组糖尿病大鼠TLR4、NF-κB持续表达阳性,B组仅术后3d、1周TLR4表达阳性,术后1周NF-κB表达阳性,C组TLR4和NF-κB表达为阴性。各组TLR4、NF-κB表达差异有统计学意义(P<0.05)。结论糖尿病大鼠NSCs视网膜下移植后TLR4、NF-κB可持续表达。

Objective Activation of nuclear factor-kappa B（NF-κB） and toll-like receptor 4（TLR4） play major roles in the inflammatory and immune responses and cellular growth properties. Present study was to observe the expression of TLR4 and NF-κB in streptozotocin-induced diabetic rats after transplantation of neural stem cells （NSCs） into subretinal space. Methods Diabetic model was induced in 80 Wistar rats by injection of streptozotocin （STZ） intraperitondally. The diabetic rats were randomly divided into group A, group B and group C. NSCs was transplanted into the subretinal space of the right eyes in group A, and DMEM was transplanted at the same way in the rats of group B. The non-operation rats were assigned to group C. In NSCs group ,uppertemple retina of two eyes in a rat was chosen after operation. Expression of TLR4 and NF-κB in retina was detected by Western blot. Results Cultured stem cells showed positive fluorescence staining for Nestin and positive reaction for NSE and GFAP. TLR4 was expressed in 3 days,1 week,2 weeks and 4 weeks in group A and only in 3 days and 1 week in group B. No TLR4 and NF-KB expressions were seen in group C. NF-κB was expreessed in 3 days,1 week,2 weeks and 4 weeks in group A and only 1 week in group B. Expression level of NF-KB protein was higher in the right eyes of experimental rats than the left eyes （P 〈0. 05）. Conclusion In diabete rats, the protein of TLR4, NF-κB has a long-term expression after the NSCs subretinal transplantation. This result suggests that NSCs induce serious inflammation or immunization procedure.