Neuroprotective effects of BDNF and GDNF in intravitreally transplanted mesenchymal stem cells after optic nerve crush in mice

AIM： To assess the neuro-protective effect of bone marrow mesenchymal stem cells （BMSCs） on retinal ganglion cells （RGCs） following optic nerve crush in mice. METHODS： C56BL/6J mice were treated with intravitreal injection of PBS, BMSCs, BDNF-interference BMSCs （BIM）, and GDNF-interference BMSCs （GIM） following optic nerve crush, respectively. The number of surviving RGCs was determined by whole-mount retinas and frozen sections, while certain mRNA or protein was detected by q-PCR or ELISA, respectively.RESULTS： The density （cell number/mm^2） of RGCs was 410.77±56.70 in the retina 21d after optic nerve crush without any treatment, compared to 1351.39±195.97 in the normal control （P〈0.05）. RGCs in BMSCs treated eyes was 625.07±89.64/mm^2, significantly higher than that of no or PBS treatment （P〈0.05）. While RGCs was even less in the retina with intravitreal injection of BIM （354.07±39.77） and GIM （326.67±33.37） than that without treatment （P〈0.05）. BMSCs injection improved the internal BDNF expression in retinas.CONCLUSION： Optic nerve crush caused rust loss of RGCs and intravitreally transplanted BMSCs at some extent protected RGCs from death. The effect of BMSCs and level of BDNF in retinas are both related to BDNF and GDNF expression in BMSCs.

兔视网膜下非活动载片植入后视网膜免疫组织化学观察

目的观察兔视网膜下非活动载片植入后视网膜相关蛋白的表达。方法健康成年新西兰白兔27只，随机分为手术组、伪手术组及对照组，3组分别为12、12、3只兔。手术组和伪手术组再分为手术后7、15、30、60d亚组，每组随机分配3只兔，手术组为非活动载片植入，伪手术组非活动载片植入随即取出。于手术后7、15、30、60d处死动物后进行免疫组织化学染色，对照组于饲养30d后处死动物行免疫组织化学染色，观察胶质纤维酸性蛋白（GFAP）和脑源性神经营养因子（BDNF）在视网膜的表达。结果手术组手术后7、15、30d组载片上外层视网膜明显变薄，内层细胞排列紊乱；60d组胶质细胞增生，手术组载片上视网膜GFAP和BDNF阳性表达均较伪手术组和对照组增加，伪手术组GFAP和BDNF阳性表达均较对照组增加，各组内各时间点间GFAP和BDNF表达未见明显差异。结论载片植入后局部视网膜神经保护相关蛋白表达升高，提示载片植入可能有神经保护作用参与，但其作用有限。