锌指蛋白A20拮抗庆大霉素致豚鼠耳蜗毛细胞损伤的实验研究

Experimental study of zinc finger protein A20 antagonizing gentamicin-induced damage of guinea pig cochlear hair cells

目的探讨细胞保护性基因锌指蛋白A20对内耳毛细胞的保护作用,为修复受损的听功能提供方法。方法采用锌指蛋白A20基因重组腺病毒(pAdEeay-1/A20)耳蜗圆窗膜显微注射,通过免疫组织化学染色、扫描电镜、ABR等办法,观察其在庆大霉素(GM)损伤条件下对毛细胞的保护作用。结果功能上,pAdEeay-1/A20/GM组和人工外淋巴液/GM组听力阈值均明显升高(P<0.05),但pAdEeay-1/A20/GM组听力损伤较轻。形态学上,pAdEeay-1/A20/GM组与pAdEeay-1/GM组、人工外淋液/GM组比较,毛细胞的损伤数目减少,电镜观察下,此组也只有少量纤毛细胞发生倒伏或缺失,内毛细胞大部分正常,也较其他实验组损伤轻。结论构建的pAdEeay-1/A20载体可有效感染毛细胞,从功能和形态上可对GM造成的毛细胞损伤起到一定的保护作用,但这种保护作用有一定的限度。

Objective To investigate the protective effect of cell protective gene zinc finger protein(A20)on the inner ear hair cells to provide a method for repairing damaged hearing function.Methods A20 gene recombinant adenoviral expression vector pAdEeay-1/A20 was injected into cochlea round window membrane.Its protective effect on hair cells under the gentamicin(GM)injury condition was observed by using the immunohistochemical staining,scanning electron microscope and ABR.Results In the function,the hearing threshold value in the pAdEeay-1/A20/GM group and artificial perilymphatic fluid/GM group was significantly increased(P<0.05),but the hearing impairment in the pAdEeay-1/A20/GM group was mild.In the morphology,compared with the pAdEeay-1/GM group and artificial perilymphatic fluid/GM group,the number of hair cells injury in the pAdEeay-1/A20/GM group was decreased,under the electronic microscopic observation,only a small amount of ciliated cells in this group developed lodging or deletion,the majority of inner hair cells were normal,their damage was milder than that in the other experiment groups.Conclusion The constructed recombinant pAdEeay-1/A20 adenoviral vector can effectively infect the hair cells and play a certain protective role on the injury of hair cells caused by GM in terms of function and morphology,but this protective effect has a certain limit.