Objectives: To study the protective effect of melatonin (Mel) against oxygen-induced retinopathy (OIR) in neonatal mice and the role of the HMGB1/NF-κB/NLRP3 axis.
Methods: Neonatal C57BL/6J mice, aged 7 days, were randomly divided into a control group, a model group (OIR group), and a Mel treatment group (OIR+Mel group), with 9 mice in each group. The hyperoxia induction method was used to establish a model of OIR. Hematoxylin and eosin staining and retinal flat-mount preparation were used to observe retinal structure and neovascularization. Immunofluorescent staining was used to measure the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis and lymphocyte antigen 6G. Colorimetry was used to measure the activity of myeloperoxidase.
Results: The OIR group had destruction of retinal structure with a large perfusion-free area and neovascularization, while the OIR+Mel group had improvement in destruction of retinal structure with reductions in neovascularization and perfusion-free area. Compared with the control group, the OIR group had significant increases in the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis, the expression of lymphocyte antigen 6G, and the activity of myeloperoxidase (P<0.05). Compared with the OIR group, the OIR+Mel group had significant reductions in the above indices (P<0.05). Compared with the control group, the OIR group had significant reductions in the expression of melatonin receptors in the retina (P<0.05). Compared with the OIR group, the OIR+Mel group had significant increases in the expression of melatonin receptors (P<0.05).
Conclusions: Mel can alleviate OIR-induced retinal damage in neonatal mice by inhibiting the HMGB1/NF-κB/NLRP3 axis and may exert an effect through the melatonin receptor pathway.
目的: 观察褪黑素（melatonin，Mel）对新生小鼠氧诱导视网膜病变（oxygen-induced retinopathy，OIR）的保护作用，并探讨HMGB1/NF-κB/NLRP3轴在其中的作用。方法: 7日龄C57BL/6J新生小鼠随机分为对照组、模型组（OIR组）及Mel处理组（OIR+Mel组），各组n=9。采用高氧诱导法制备OIR模型。苏木精-伊红染色和视网膜铺片法检测视网膜结构和新生血管；免疫荧光染色法检测HMGB1/NF-κB/NLRP3轴相关蛋白和炎性因子及淋巴细胞抗原6G表达；比色法检测髓过氧化物酶活性。结果: OIR组视网膜结构被破坏，出现大片无灌注区和新生血管，OIR+Mel组可见破坏的视网膜结构改善，新生血管和无灌注区减少。与对照组相比，OIR组HMGB1/NF-κB/NLRP3轴相关蛋白和炎性因子表达升高（均P<0.05），淋巴细胞抗原6G表达和髓过氧化物酶活性升高（均P<0.05）；Mel处理后，上述各指标降低（均P<0.05）。与对照组相比，OIR组视网膜中褪黑素受体表达降低；Mel处理后，褪黑素受体表达较OIR组升高（均P<0.05）。结论: Mel可能通过抑制HMGB1/NF-κB/NLRP3轴减轻OIR新生小鼠视网膜损伤，且可能通过褪黑素受体途径发挥作用。.
Keywords: HMGB1/NF-κB/NLRP3 axis; Inflammation; Melatonin; Neonatal mouse; Oxygen-induced retinopathy.