目的:观察N-乙酰5-羟色胺(NAS)对大鼠视网膜缺血再灌注(RIR)损伤的影响,探讨高迁移率族蛋白B1(HMGB1)/糖基化终产物受体(RAGE)/核因子-κB(NF-κB)信号通路的作用机制。
方法:通过增加眼前房的压力来建立RIR的大鼠模型。将80例雄性SpragueDawley随机分为5组:假手术组(n=8),RIR组(n=28),RIR+NAS组(n=28),RIR+FPS-ZM1组(n=8)和RIR+NAS+FPS-ZM1组(n=8)。通过苏木精-伊红(H&E)染色检查NAS的治疗效果,和视网膜神经节细胞(RGC)计数。白细胞介素1β(IL-1β)的表达,HMGB1,RAGE,通过免疫组织化学染色和Westernblot分析nod样受体3(NLRP3)蛋白和核因子κB(p-NF-κB)的磷酸化。酶联免疫吸附试验(ELISA)检测HMGB1蛋白的表达。
结果:H&E染色结果显示,NAS显着减轻了RIR大鼠的视网膜水肿并增加了RGCs的数量。使用NAS治疗,HMGB1和RAGE表达显著降低,NF-κB/NLRP3通路的激活与p-NF-κB和NLRP3蛋白表达的抑制同时被拮抗。此外,NAS通过降低IL-1β表达表现出抗炎作用。RAGE抑制剂FPS-ZM1抑制RAGE与HMGB1的结合导致p-NF-κB和NLRP3表达显著降低,从而对IL-1β的表达和视网膜水肿,在RIR大鼠中伴有RGC的增加。
结论:NAS可能通过HMGB1/RAGE/NF-κB信号通路表现出对RIR的神经保护作用,这可能是一个有用的治疗视网膜疾病的目标。
OBJECTIVE: To observe the effects of N-acetylserotonin (NAS) administration on retinal ischemia-reperfusion (RIR) injury in rats and explore the underlying mechanisms involving the high mobility group box 1 (HMGB1)/receptor for advanced glycation end-products (RAGE)/nuclear factor-kappa B (NF-κB) signaling pathway.
METHODS: A rat model of RIR was developed by increasing the pressure of the anterior chamber of the eye. Eighty male Sprague Dawley were randomly divided into five groups: sham group (n=8), RIR group (n=28), RIR+NAS group (n=28), RIR+FPS-ZM1 group (n=8) and RIR+NAS+ FPS-ZM1 group (n=8). The therapeutic effects of NAS were examined by hematoxylin-eosin (H&E) staining, and retinal ganglion cells (RGCs) counting. The expression of interleukin 1 beta (IL-1β), HMGB1, RAGE, and nod-like receptor 3 (NLRP3) proteins and the phosphorylation of nuclear factor-kappa B (p-NF-κB) were analyzed by immunohistochemistry staining and Western blot analysis. The expression of HMGB1 protein was also detected by enzyme-linked immunosorbent assay (ELISA).
RESULTS: H&E staining results showed that NAS significantly reduced retinal edema and increased the number of RGCs in RIR rats. With NAS therapy, the HMGB1 and RAGE expression decreased significantly, and the activation of the NF-κB/NLRP3 pathway was antagonized along with the inhibition of p-NF-κB and NLRP3 protein expression. Additionally, NAS exhibited an anti-inflammatory effect by reducing IL-1β expression. The inhibitory of RAGE binding to HMGB1 by RAGE inhibitor FPS-ZM1 led to a significant decrease of p-NF-κB and NLRP3 expression, so as to the IL-1β expression and retinal edema, accompanied by an increase of RGCs in RIR rats.
CONCLUSIONS: NAS may exhibit a neuroprotective effect against RIR via the HMGB1/RAGE/NF-κB signaling pathway, which may be a useful therapeutic target for retinal disease.