膳食诱导的肥胖型 C57 BL／6小鼠视网膜神经节细胞凋亡的机制

目的：探讨高脂饮食诱导的C57 BL/6肥胖小鼠视网膜神经节细胞（ RGCs）凋亡的机制。 方法：高脂饲料喂养19 wk后，小鼠分为肥胖抵抗（ DIO-R）组和肥胖倾向（ DIO）组，同时对照组（ CON）小鼠给予基础饲料。 TUNEL法检测各组小鼠RGCs的凋亡情况，并应用激光共聚焦显微镜检测RGCs内钙离子的浓度。 结果：TUNEL法凋亡检测结果显示，DIO组小鼠视网膜神经节细胞层可见较多黄色着染的凋亡细胞，其凋亡指数为（6．7±1．2）％，显著高于对照组和DIO-R组（P＜0．01， P＜0．05）；对照组和DIO-R组间比较无显著差异（ P＞0.05）。激光共聚焦结果显示，与对照组和DIO-R组比较，DIO组小鼠视网膜神经节细胞内Ca2＋荧光染色明显增强，其荧光染色强度比值显著升高（均P＜0．01）；对照组和DIO-R组视网膜神经节细胞内Ca2＋荧光染色强度无明显差异（P＞0．05）。 结论：细胞内钙离子超载可能介导了肥胖型C57 BL/6小鼠视网膜神经节细胞的凋亡过程。

Mechanism of retinal ganglion cells apoptosis in the diet -induced obese C57 BL/6 mice

AIM：To investigate the mechanism of retinal ganglion cells （RGCs） apoptosis in the diet-induced obese C57BL/6 mice. METHODS： Mice were fed high-fat diet. After 19 weeks of feeding, the mice were divided into diet induced obesity-resistant （ DIO-R ） group and diet induced obesity （ DIO） group, while mice of the control （ CON） group were fed a basal diet at the same time. The apoptosis of RGCs was detected by TUNEL.Laser scanning confocal microscope was used to detect the intracellular calcium ion concentration. RESULTS： TUNEL staining showed apoptosis cells in ganglion cell layer （ GCL） in DIO group increased and the percentage of apoptotic cells was （6.7±1.2）%which was much higher than in CON and DIO-R groups （ P〈0.01, P〈0.05）.There was no significant difference between CON group and DIO-R group （ P〉0.05 ）.Laser scanning confocal microscope detection showed Ca2＋ staining intensity of RGCs in DIO group increased and its staining＆amp;nbsp;intensity was significantly higher than in CON and DIO-R mice （P〈0.01,P〈0.01）, whereas there was no significant difference between CON group and DIO-R group （ P〉0.05 ） . CONCLUSION：Intracellular calcium ion overload might be involved in the RGCs apoptosis in the diet-induced obese C57BL/6 mice.