为了探究自噬抑制剂3-甲基腺嘌呤（3-MA）在糖尿病小鼠模型（DM）中的作用及其潜在机制。雄性C57BL/6J小鼠随机分为正常对照组（NC组）和DM组。通过多次低剂量腹腔注射链脲佐菌素（STZ）（60 mg/kg·d，连续5天）诱导DM。DM小鼠随机分为未处理组（DM组），3-MA（10 mg/kg·d，口服）处理组（DM+3-MA组）和氯喹（CQ；50 mg/kg，腹腔注射）处理组（DM+CQ组）。每周记录空腹血糖（FBG）水平。实验结束时，采集视网膜样本。通过Western blot检测裂解的半胱天冬氨酸蛋白酶-3（cleaved caspase-3），裂解的聚腺苷酸二磷酸核糖聚合酶1（cleaved poly ADP-ribose polymerase 1，PARP1）和Bax等前大家促凋亡蛋白，抗凋亡蛋白Bcl-2，纤维连接蛋白和1型胶原α1链（COL1A1）等纤维化相关蛋白，血管内皮生长因子（Vascular endothelial growth factor，VEGF），炎症因子白细胞介素-1β（interleukin-1β，IL-1β）和肿瘤坏死因子-α（tumor necrosis factor-α，TNF-α），以及自噬相关蛋白LC3、Beclin-1和P62的表达水平。采用商业试剂盒检测氧化应激指标8-羟基脱氧鸟苷（8-hydroxydeoxyguanosine，8-OHdG）和丙二醛（malondialdehyde，MDA）。3-MA和CQ对DM小鼠的FBG具有短期降糖作用，并减少了VEGF以及炎症因子IL-1β和TNF-α的表达。3-MA还显著缓解了氧化应激指标8-OHdG和MDA的水平，降低了纤维化相关蛋白纤维连接蛋白和COL1A1的表达，前大家促凋亡蛋白cleaved caspase-3，cleaved PARP1以及Bax/Bcl-2比值。CQ对氧化应激指标、纤维化和凋亡相关蛋白没有显著影响。Western blot检测结果显示，3-MA治疗降低了DM小鼠视网膜LC3 II/LC3 I比值和Beclin-1的表达，CQ治疗进一步增加了P62的表达。3-MA对DM小鼠视网膜具有抗凋亡和抗纤维化作用，并能减轻视网膜氧化应激、VEGF表达和炎症因子的产生。3-MA上述作用的潜在机制可能与其抑制早期自噬和降糖作用有关。 《国际眼科学杂志》出版社。

To investigate the role of autophagy inhibitor 3-methyladenine (3-MA) on a diabetic mice model (DM) and the potential mechanism.Male C57BL/6J mice were randomly divided into a normal control group (NC group) and an DM group. DM were induced by multiple low-dose intraperitoneal injection of streptozotocin (STZ) 60 mg/kg·d for 5 consecutive days. DM mice were randomly subdivided into untreated group (DM group), 3-MA (10 mg/kg·d by gavage) treated group (DM+3-MA group) and chloroquine (CQ; 50 mg/kg by intraperitoneal injection) treated group (DM+CQ group). The fasting blood glucose (FBG) levels were recorded every week. At the end of experiment, retinal samples were collected. The expression levels of pro-apoptotic proteins cleaved caspase-3, cleaved poly ADP-ribose polymerase 1 (PARP1) and Bax, anti-apoptotic protein Bcl-2, fibrosis-associated proteins Fibronectin and type 1 collagen α1 chain (COL1A1), vascular endothelial growth factor (VEGF), inflammatory factors interleukin (IL)-1β and tumor necrosis factor (TNF)-α, as well as autophagy related proteins LC3, Beclin-1 and P62 were determined by Western blotting. The oxidative stress indicators 8-hydroxydeoxyguanosine (8-OHdG) and malondialdehyde (MDA) were detected by commercial kits.Both 3-MA and CQ had short-term hypoglycemic effect on FBG and reduced the expression of VEGF and inflammatory factors IL-1β and TNF-α in DM mice. 3-MA also significantly alleviated oxidative stress indicators 8-OHdG and MDA, decreased the expression of fibrosis-related proteins Fibronectin and COL1A1, pro-apoptotic proteins cleaved caspase-3, cleaved PARP1, as well as the ratio of Bax/Bcl-2. CQ had no significant impact on the oxidative stress indicators, fibrosis, and apoptosis related proteins. The results of Western blotting for autophagy related proteins showed that the ratio of LC3 II/LC3 I and the expression of Beclin-1 in the retina of DM mice were decreased by 3-MA treatment, and the expression of P62 was further increased by CQ treatment.3-MA has anti-apoptotic and anti-fibrotic effects on the retina of DM mice, and can attenuate retinal oxidative stress, VEGF expression and the production of inflammatory factors in the retina of DM mice. The underlying mechanism of the above effects of 3-MA may be related to its inhibition of early autophagy and hypoglycemic effect.International Journal of Ophthalmology Press.