Objective: To explore the protective effect of SBi4211 (heptamidine), an inhibitor of S100B, against central nervous system injury induced by HIV-1 envelope protein gp120.
Methods: In an in vitro model, U251 glioma cells were co-cultured with SH-SY5Y cells to explore the protective effect of SBi4211 against gp120-induced central nervous system injury. In a gp120 transgenic (Tg) mouse model (8 months old) mimicking HIV-associated neurocognitive disorder (HAND), the effect of treatment with gp120 or both gp120 and SBi4211 on neuronal activity and apoptosis were assessed using Cell Counting kit-8 (CCK-8) and flow cytometry. ELISA, Western blotting and immunohistochemistry were used to determine the expression levels of S100B, RAGE, GFAP, NeuN, Syn, MAP-2 and the inflammatory factors IL-6 and TNF-α.
Results: In the cell co-culture system, SBi4211 treatment significantly inhibited gp120-induced expression of S100B, RAGE and GFAP in U251 cells (P < 0.001), reduced the levels of inflammatory factors iNOS, IL-6 and TNF-α (P < 0.001) and enhanced the expressions of neuron-related proteins NeuN, Syn and MAP-2 (P < 0.001). In the transgenic mouse model, SBi4211 treatment significantly reduced the expressions of S100B, RAGE and inflammation levels (P < 0.05), inhibited the activation of astrocytes in the brain, and maintained the integrity of the neurons (P < 0.05).
Conclusions: SBi4211 can protect neurons from gp120-induced neurotoxicity possibly by inhibiting the S100B/ RAGE-mediated signaling pathway.
目的: 研究S100B抑制剂SBi4211（heptamidine）在人类免疫缺陷病毒-1（HIV-1）包膜蛋白gp120损伤中枢神经系统的作用。
方法: 通过U251细胞和SH-SY5Y细胞建立非接触式星形胶质细胞-神经元共培养体系，由gp120蛋白处理U251细胞激活神经炎症反应造成神经元损伤，体外水平探讨SBi4211在gp120诱导的中枢神经毒性中的作用；体内实验中，以8月龄gp120转基因小鼠模拟HIV相关神经认知障碍（HAND）模型，实验分为对照组、gp120组以及gp120+SBi4211组（SBi4211处理组）。采用CCK-8、流式细胞术检测神经元活性及凋亡情况，ELISA检测S100B及炎症因子IL-6、TNF-α表达水平，Western blot和免疫组织化学染色分析RAGE、GFAP、NeuN、Syn、MAP-2蛋白表达情况。
结果: 体外实验结果显示SBi4211可以显著抑制gp120刺激后U251细胞S100B、RAGE的表达（P < 0.001），降低炎症因子iNOS、IL-6和TNF-α的表达水平（P < 0.001），维持神经元相关标记蛋白NeuN、Syn的表达（P < 0.001）。体内实验结果显示SBi4211显著降低gp120转基因小鼠S100B、RAGE表达及炎症水平（P < 0.05），并且抑制脑内星形胶质细胞活化，保护神经元的完整性（P < 0.05）。
结论: SBi4211可能通过下调S100B/RAGE表达，抑制gp120引发的神经炎症反应，继而阻断gp120的中枢神经毒性作用。
Keywords: HIV-associated neurocognitive disorder; S100B/RAGE; SBi4211; gp120.