缺氧对少突胶质前体细胞内NLRP3炎症小体表达的影响

Effect of hypoxia on expression of NLRP3 inflammasome in oligodendrocyte precursor

目的:观察缺氧对少突胶质前体细胞(preOL)内Nod样受体热蛋白结构域相关蛋白3(NLRP3)及细胞凋亡相关斑点样蛋白(ASC)表达的影响。方法:将体外分离纯化的preOL分为正常组和缺氧组,1%O25%CO2、37℃缺氧培养箱培养9 h建立preOL缺氧损伤模型。TUNEL法检测细胞凋亡,免疫荧光染色、qRT-PCR及Western Blot检测NLRP3表达,Western Blot检测ASC表达。结果:preOL缺氧损伤后胞质内出现空泡,胞膜破裂,突起出现肿胀、断裂;凋亡率较正常组增加(P<0.05);缺氧组NLRP3阳性细胞数和平均荧光强度均较正常组增加(P<0.05),NLRP3的mRNA及蛋白水平也均较正常组增加(P<0.05);ASC蛋白的表达在缺氧后上调(P<0.05)。结论:preOL的缺氧损伤可能与激活NLRP3炎症小体有关。

Objective： The purpose of this study was to observe the expression of Nod like receptor pyrin domain containing 3（ NLRP3） and apoptosis-associated speck-like protein containing a CARD（ ASC） in oligodendrocyte precursor（ preOL） affected by hypoxia damage. Methods： The preOL of cerebral cortex of SD rats were divided into normal group and hypoxia group. The preOL hypoxia damage was induced under the condition with 1% O25% CO2,37℃for 9 hours. The apoptosis was assessed by TUNEL staining. The expression of NLRP3 was measured by immunocytochemical staining,qRT-PCR and Western Blot. Western Blot was also adopted to detect the expression of ASC.Results： After hypoxia damage,the morphology of preOL was obviously changed： vacuoles appeared in cytoplasm,part of membrane dissolved,cell processes swelled and ruptured gradually. TUNEL staining results showed that the apoptosis in hypoxia group was increased compared with normal group（ P〈0. 05）. Both of the number of NLRP3 positive and mean intensity of NLRP3 immunofluoresence were increased in hypoxia group compared with the normal group（ P〈0. 05）. nlrp3 mRNA and protein levels were also elevated compared with the normal group（ P〈0. 05）. The expressionof ASC increased by hypoxia damage（ P〈0. 05 vs normal group）. Conclusion： Hypoxia anight activate NLRP3 inflammasome and involve in hypoxia damage of preOL.