白及多糖在小鼠烟曲霉菌性角膜炎中的抗炎作用

Anti-inflammatory effect of Bletilla striata polysaccharides in mice with Aspergillus fumigatus keratitis

目的研究白及多糖(BSP)在小鼠烟曲霉菌性角膜炎中的抗炎机制,探讨BSP对真菌性角膜炎的治疗作用。方法建立小鼠烟曲霉菌性角膜炎模型,使用BSP水溶液局部滴眼处理,裂隙灯下观察感染后第1、3、5天小鼠角膜的炎症程度,反转录-聚合酶链反应法检测小鼠角膜中炎症因子和模式识别受体Dectin-1的mRNA水平,酶联免疫吸附试验和蛋白免疫印迹法检测炎症因子和Dectin-1蛋白的表达。结果BSP处理的小鼠角膜炎症评分在感染后第3、5天明显低于对照组(F=6.64、11.58,P<0.05)。16 g/L的BSP水溶液可以降低小鼠角膜中炎症因子白细胞介素1β、白细胞介素6、肿瘤坏死因子α以及模式识别受体Dectin-1的mRNA和蛋白表达水平,差异均具有统计学意义(F=2.21~97.39,P<0.05)。结论BSP通过下调炎症因子水平和抑制模式识别受体Dectin-1的表达在小鼠烟曲霉菌性角膜炎中发挥抗炎作用。

Objective To investigate the anti-inflammatory mechanism of Bletilla striata polysaccharides(BSP)in a mouse model of Aspergillus fumigatus keratitis and the therapeutic effect of BSP on fungal keratitis.Methods A mouse model of fungal keratitis(FK)was established,and BSP solution was used for local treatment as eye drops.A slit lamp was used to observe the severity of keratitis on days 1,3,and 5 after infection;RT-PCR was used to measure the mRNA expression levels of inflammatory cytokines and the pattern recognition receptor Dectin-1 in mouse cornea,and ELISA and Western blotting were used to measure the protein expression levels inflammatory cytokines and Dectin-1.Results The BSP group had a significantly lower clinical score of corneal inflammation than the control group on days 3 and 5 after infection(F=6.64,11.58,P<0.05).BSP solution at a concentration of 16 g/L significantly reduced the mRNA and protein expression levels of the inflammatory cytokines interleukin-1β,interleukin 6,and tumor necrosis factor-αand the pattern recognition receptor Dectin-1 in mouse cornea(F=2.21-97.39,P<0.05).Conclusion BSP exerts an anti-inflammatory effect in mice with A.fumigatus keratitis by downregulating the expression levels of inflammatory cytokines and inhibiting the expression of the pattern recognition receptor Dectin-1.