NgR在糖皮质激素诱导视网膜神经节细胞凋亡中的作用

Role of Nogo receptor in glucocorticoids-induced apoptosis of retinal ganglion cell

目的:探讨糖皮质激素对视网膜神经节细胞(retinal ganglion cell,RGC)凋亡的影响及机制。方法:分4组培养RGC,即(1)对照组,(2)激素组(0.1μmol/L可的松),(3)激素-siNgR组(0.1μmol/L可的松+NgR反义核苷酸病毒),(4)激素-scRNA对照组(0.1μmol/L可的松+阴性核苷酸病毒)。3d后四甲基噻唑蓝(Thiazolyl blue tetrazolium bromide,MTT)检测细胞活力变化,倒置显微镜观察细胞形态学变化,Hoechst 33342染色检测细胞凋亡,Western blot检测Nogo受体(Nogo receptor,NgR)表达。结果:对照组、激素组、激素-scRNA组及激素-siNgR组细胞活力分别为(100.0±0.0)%,(76.3±6.8)%,(79.4±9.0)%及(96.7±9.8)%,与对照组相比,激素组及激素-scRNA组细胞活力明显降低,细胞密度降低,体积缩小,NgR表达增加(P<0.01),而激素-siNgR组无明显变化(P>0.05)。Hoechst 33342染色显示,对照组及激素-siNgR组细胞淡蓝色,激素组及激素-scRNA组可见大量呈亮蓝色的凋亡细胞。结论:糖皮质激素能通过NgR表达增加诱导RGC凋亡。

AIM： To explore the effects and underlying mechanisms of glucocorticoid in the apoptosis of retinal ganglion cell （RGC）. METHODS： RGC were cultured in 4 groups for 3d： control group, glucocorticoid group （with 0. 1μmol/L cortisone）, glucocorticoid-siNgR group [ with 0. 1μ mol/L cortisone＋ Nogo receptor （NgR） antisense nucleotide ], glucocorticoid-scRNA group （with 0. 1μ mol/L cortisone ＋ scrambled nucleotide）. The cell viability was detected by thiazolyl blue tetrazolium bromide （ MTT ）, the morphological features were observed with inverted microscope, apoptosis of RGC was measured with Hoechst 33342 staining, and expression of NgR was revealed by Western blot. RESULTS： Cell viability in control, glucocorticoid, glucocorticoid-scRNA and glucocorticoid-siNgR groups were （100.0±0.0） %, （76.3±6.8） %, （79.4±9.0） % and （96. 7 ± 9. 8） % respectively. Decreased cell viability, reduced cell number, and increased expression of NgR were atrophic cell body detected in glucocorticoid and glucocorticoid - scRNA groups （ P 〈 0, 01 ）, not in glucocorticoid- siNgR group （ P〉 0. 05）, compared with control group. RGC was showed light blue by Hoechst 33342 staining in control and glucocorticoid- siNgR groups, and exhibiting bright blued apoptotic RGC in glucocorticoid and glucocorticoid-scRNA groups. CONCLUSION： Up-regulation of NgR contributes to glucocorticoids-induced apoptosis of RGC.