基于TLR-4/NF-κB信号通路探讨半乳糖凝集素-3对大鼠脑出血后脑损伤的影响

To Investigate the Effect of Galactin-3 on Brain Injury after Cerebral Hemorrhage in Rats Based on TLR-4/NF-κB Signaling Pathway

摘要: 目的：探究半乳糖凝集素-3 (Galectin-3)对大鼠脑出血后脑损伤的影响及相关机制。方法：将120只清洁级Wistar大鼠随机分为假手术组(Sham组)、脑出血模型组(ICH组)、Galectin-3抑制剂MCP组(MCP组)，每组40只。采用胶原酶脑内定点注射法制作大鼠ICH模型，Sham组和ICH组大鼠经侧脑室注射20 μg正常绵羊IgG，MCP组大鼠注射4 μg MCP。48 h后采用Longa评分标准进行神经功能缺损评分，并检测各组大鼠脑含水量，评估血脑屏障通透性，TUNEL染色法检测神经细胞凋亡，酶联免疫吸附法(ELISA)检测白细胞介素-1β (IL-1β)、白细胞介素-6 (IL-6)和肿瘤坏死因子-α (TNF-α)含量，蛋白免疫印迹法(Western Blot)检测TLR-4/NF-κB通路相关蛋白表达。结果：与Sham组相比，ICH组大鼠神经功能缺损评分、脑含水量、血脑屏障通透性、细胞凋亡率、脑组织IL-1β、IL-6、TNF-α含量升高(P < 0.01)，脑组织Galectin-3、TLR-4、NF-κB p65蛋白表达量增加(P < 0.01)；与ICH组相比，MCP组大鼠神经功能缺损评分、脑含水量、血脑屏障通透性、细胞凋亡率、脑组织IL-1β、IL-6、TNF-α含量降低(P < 0.01)，脑组织Galectin-3、TLR-4、NF-κB p65蛋白表达量降低(P < 0.05)。结论：半乳糖凝集素-3能够增加脑出血大鼠神经细胞凋亡和炎症反应，促进脑损伤，其机制与上调TLR-4/NF-κB通路有关。

Abstract: Objective: To explore the effect of Galectin-3 on brain injury after cerebral hemorrhage in rats and its related mechanism. Methods: A total of 120 Wistar rats were randomly divided into Sham group, ICH group, Galectin-3 inhibitor MCP group (MCP group), 40 mice per group. ICH model was made by intracerebral injection of collagenase. 20 μg normal sheep IgG was injected into the lateral ventricle of Sham group and ICH group, and 4 μg MCP was injected into the MCP group. 48 h later, Longa score was used to evaluate the neural function deficit, and the brain water content of rats in each group was detected to evaluate the blood-brain barrier permeability. TUNEL staining was used to detect nerve cell apoptosis. The levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA), and the expression of TLR-4/NF-κB pathway related proteins was detected by Western Blot. Results: Compared with Sham group, the neural function deficit score, brain water content, blood-brain barrier permeability, cell apoptosis rate, the contents of IL-1β, IL-6 and TNF-α in brain tissue were increased in ICH group (P < 0.01), and the expression of Galectin-3, TLR-4 and NF-κB p65 in brain tissue were increased (P < 0.01). Compared with ICH group, the neural function deficit score, brain water content, blood-brain barrier permeability, cell apoptosis rate, the contents of IL-1β, IL-6 and TNF-α in brain tissue were decreased in MCP group (P < 0.01), and the expression of Galectin-3, TLR-4 and NF-κB p65 in brain tissue were decreased (P < 0.05). Conclusion: Galactin-3 can increase neuronal apoptosis and inflammatory response in rats with cerebral hemorrhage, and promote brain injury, the mechanism of which is related to up-regulation of TLR-4/NF-κB pathway.