摘要目的 研究人脐带间充质干细胞(hUC-MSCs)能否通过影响Notch信号通路及血管内皮生长因子受体2(VEGFR-2)对糖尿病视网膜病变(DR)起治疗作用.方法 选取周龄6～8周、体重20～24 g雌性NOD小鼠80只,适应性喂养1周后按随机数字表法将1型糖尿病发病小鼠分为糖尿病(DM)组、胰岛素(INS)组(给予甘精胰岛素干预)和干细胞(MSC)组(给予hUC-MSCs+甘精胰岛素干预),选取未发生糖尿病的NOD小鼠为正常对照(NC)组;每组10只小鼠.定期检测各组小鼠随机血糖.8周后处死小鼠,制作眼球切片,计数突破视网膜内界膜的血管内皮细胞核数;检测视网膜Notch-1蛋白胞内段(NICD)、发状分裂相关增强子1(HESR1) mRNA、VEGFR-2mRNA及蛋白的表达.多组间比较采用单因素方差分析,多组间两两比较采用最小显著性差异法(LSD)-t检验.结果 (1)四组间突破内界膜的内皮细胞核数量总体比较差异有统计学意义(F=57.247,P＜0.001),与DM组(6.4±1.0)相比,MSC组(2.8±0.5)数量显著减少(P＜0.05).(2)四组间小鼠视网膜NICD蛋白、HESR1 mRNA、VEGFR-2mRNA及蛋白表达量比较差异均有统计学意义(分别为F=155.076～562.306,均P＜0.05).与NC组相比,DM组小鼠视网膜NICD蛋白(0.38±0.18比1.74±0.11)和HESR1 mRNA(0.29±0.04比1.00±0.00)表达下降、VEGFR2 mRNA(4.11±0.40比1.00±0.00)及蛋白(1.40±0.85比0.28±0.02)表达量增加(均P＜0.05);与DM组相比,MSC组小鼠视网膜NICD蛋白(1.36±0.05比0.38±0.18)、HESR1 mRNA (0.80±0.02比0.29±0.04)表达增加,VEGFR2 mRNA(1.80±0.27比4.11±0.40)及蛋白(0.92±0.10比1.40±0.85)表达量减少,差异均有统计学意义(均P＜0.05).结论 hUC-MSCs可能通过激活Notch通路、抑制VEGFR-2来抑制视网膜新生血管形成,从而对DR起治疗作用.

abstractsObjective To investigate whether human umbilical cord mesenchymal stem cells (hUC-MSCs) can play a role in the treatment of diabetic retinopathy (DR) by affecting Notch signaling pathway and vascular endothelial growth factor receptor 2 (VEGFR-2).Methods Eighty female NOD mice aged 6-8 weeks and weighingt of 20-24 g were randomly divided into diabetes group (group DM) group,insulin group (INS) group (insulin glargine subcutaneous injection,group INS) and mesenchymal stem cells (MSC) group (hUC-MSCs + insulin glargine subcutaneous injection,group MSC) according to random number table after adaptive feeding for 1 week.NOD mice without diabetes were compared as normal control (NC) group (group NC).Each group had 10 mice.Random blood glucose was detected regularly.All the mice were sacrificed after 8 weeks.The number of vascular endothelial nuclei beyond the inner limiting membrane of retina were counted.The mRNA expressions of VEGFR-2 and hairy and enhancer of split related 1 (HESR1),as well as the protein expressions of VEGFR-2 and Notch-1 intracellular domain (NICD) of retina were detected.Oneway analysis of variance (ANOVA) was used for comparison among multiple groups.The least-significant difference (LSD)-t test was used for comparison between two groups after ANOVA.Results (1) The difference in the number of endothelial nuclei beyond the inner limiting membrane of retina among four groups was statistically significant (F=57.247,P＜0.001).The number was significantly lower in MSC group (2.8±0.5) than that in DM group (6.4± 1.0) (P＜0.05).(2) There were significant differences in the expression of NICD protein,HESR1 mRNA,VEGFR-2 mRNA and protein of retina among four groups (F=155.076-562.306,all P＜0.05).Compared with NC group,the expression of NICD protein (0.38±0.18 vs 1.74±0.11) and HESR1 mRNA (0.29±0.04 vs 1.00±0.00) decreased significantly,the expression of VEGFR2 mRNA (4.11 ±0.40 vs 1.00±0.00) and protein (1.40±0.85 vs 0.28±0.02) increased significantly in DM group(all P＜0.05).Compared with DM group,the expression of NICD protein (1.36±0.05 vs 0.38±0.18) and HESR1 mRNA (0.80±0.02 vs 0.29±0.04) increased significantly,meanwhile the expression of VEGFR2 mRNA (1.80±0.27 vs 4.11± 0.40) and protein (0.92 ± 0.10 vs 1.40 ± 0.85) decreased significantly in MSC group (all P＜0.05).Conclusion hUC-MSCs may inhibit the formation of retinal neovascularization by activating Notch signaling pathway and inhibiting VEGFR-2,and may be helpful for the treatment of DR.