OBJECTIVE: Our work aimed to elucidate the effect and mechanism of NXS on hematoma absorption in rats with ICH.
METHODS: Induction of ICH model in the rats with intracerebral injection of collagenase VII, followed by treatment with NXS and Edaravone as a control neuroprotection medication. Neural functional recovery was assessed using mNSS, foot fault test, corner test, forelimb grip-traction test, and adhesive removal test. Hematoma absorption was assessed by the spectrophotometric hemoglobin assay with Drabkin\'s reagent. The protein expression of CD36, M2 microglia marker (CD206 and YM-1) and TLR4/MyD88/NF-κB pathway related proteins were determined by Western blot and immunofluorescence.
RESULTS: NXS could significantly ameliorate the ICH recovery of neural and locomotor function as well as reduce hemorrhage volume. NXS could increase the expression of CD36 expressed in M2 microglia and promote M2 microglia polarization. Simultaneously, NXS significantly suppressed protein expressions of TLR4, MyD88, and NF-κB following ICH in rats. The results indicated that lipopolysaccharide (LPS), TLR4 specific agonist, could partially reverse the change in ICH rats administrated with NXS.
CONCLUSIONS: NXS promotes hematoma absorption by targeting CD36 expression in M2 microglia via TLR4/MyD88/NF-κB signaling pathway in rats with ICH. Collectively, current research provides a novel theoretical basis for the clinical application of NXS.
目的:我们的工作旨在阐明NXS对ICH大鼠血肿吸收的影响及其机制。
方法:脑内注射胶原酶VII诱导大鼠ICH模型,然后用NXS和依达拉奉作为对照神经保护药物治疗。使用mNSS评估神经功能恢复,足部故障测试,转角测试,前肢抓力牵引试验,和粘合剂去除试验。用Drabkin试剂通过分光光度血红蛋白测定法评估血肿吸收。采用Westernblot和免疫荧光法检测CD36、M2小胶质细胞标志物(CD206和YM-1)和TLR4/MyD88/NF-κB通路相关蛋白的表达。
结果:NXS能显著改善ICH神经和运动功能的恢复,减少出血量。NXS可以增加M2小胶质细胞中CD36的表达,促进M2小胶质细胞极化。同时,NXS显著抑制大鼠脑出血后TLR4、MyD88和NF-κB蛋白的表达。结果表明,脂多糖(LPS),TLR4特异性激动剂,可以部分逆转ICH大鼠服用NXS的变化。
结论:NXS通过TLR4/MyD88/NF-κB信号通路靶向M2小胶质细胞CD36的表达促进血肿吸收。总的来说,目前的研究为NXS的临床应用提供了新的理论依据。