强化铁营养对铁缺乏大鼠耳蜗膜性结构基因表达的影响  

Effects of Fortified Iron Nutrition on Gene Expression in the Membranous Cochlea of Iron-Deficient Rats

作　　者：孙爱华[1] 田树昌[1] 王秋莎[2] 范静平[1] 林顺涨 吴建[1] 杨毓梅[1] 王宝东[1] 

机构地区：[1]第二军医大学长征医院耳鼻咽喉科,上海200003 [2]南京医科大学附属常州第二人民医院高压氧科

出　　处：《听力学及言语疾病杂志》2007年第4期299-302,306,I0002,共6页Journal of Audiology and Speech Pathology

基　　金：国家自然科学基金资助项目(编号30472124)

摘　　要：目的 应用基因表达谱芯片研究强化铁营养对铁缺乏耳聋Wistar大鼠耳蜗膜性结构基因表达的影响.方法体重28～45 g、健康、无耳疾、ABR反应阈值正常的幼龄Wistar大鼠66只,随机分成正常对照组12只,标准饲料喂养12周;缺铁大鼠组54只,以缺铁饲料喂养法建立缺铁模型,饲养8周后,复制出至少有一耳ABR阈值改变≥15 dB的大鼠共21只,再将该21只大鼠随机分成缺铁耳聋组11只,补铁治疗组10只,缺铁耳聋组继续喂以缺铁饲料4周,补铁治疗组喂以强化铁饲料4周.将包含了4096条的大鼠靶基因用点样仪点在特制玻片上制备成表达谱芯片,分别取缺铁耳聋组（与正常对照组比较）、强化铁治疗组（与缺铁耳聋组比较）的耳蜗膜性组织mRNA,通过逆转录方法,将Cy3和Cy5两种荧光分别标记到两种组织的cDNA上,制成cDNA探针,并与表达谱芯片进行杂交及扫描.筛选出部分差异表达基因,另用RT-PCR验证.结果缺铁耳聋组与正常对照组比较：前者筛选出差异表达基因896条,其中上调基因447条,下调基因449条.肌动蛋白基因及其相关调节蛋白基因的表达发生了改变,其中肌动蛋白基因Arpclb、Actcl、Actb、Actal都表现为下调,肌动蛋白的抑制蛋白基因ProfilinⅡ上调.细胞骨架蛋白Tubulin、Myosin和热休克蛋白（heat shock protein,HSP）下调.强化铁治疗组与缺铁耳聋组比较：前者筛选出差异表达基因355条,其中上调基因128条,下调基因227条.细胞骨架蛋白Tubulin、Myosin和热休克蛋白（HSP）上调,肌动蛋白基因表达没有发生明显改变.从中选取5条差异表达基因：BC072490（Ctsb）、CF111145（Actb）、NM013146（Cald1）、AB011679（Tubb5）、BC063175（ctsl）,用RT-PCR验证,RT-PCR结果与基因芯片结果基本一致.结论铁缺乏通过影响耳蜗膜性结构中多种基因的表达,包括肌动蛋白基因及其相关调节蛋白基因的表达,从而导致感音神经性聋.强化铁营养可Objective To study the effects of fortified iron nutrition on gene expression in the membranous cochlea of iron - deficient rats. Methods Sixty - six growing W-istar rats with normal hearing were randomly devided into two groups. In groupA, 12 animals were given the final iron - supplemented diet for 12 weeks. In groupX, 54 rats were fed with the basic iron - deficient diet for 8 weeks to establish a hearing loss models due to iron deficiency. In Group X, twenty - one rats with hearing loss caused by iron deficiency were then randomly devided into 2 groups： B（11 rats） and C（10 rats）. The rats of group B were fed with iron deficiency diet for another 4 weeks while group C rats were fed with fortified iron nutrition diet for another 4 weeks. Two cDNA probes labelled with Cy3 or Cy5 fluorescence dyes were prepared from mRNA of the cochlear of B/A and were hybridized with cDNA microarray of target gene expression profile which were scanned for fluorescent intensity. The mixed probes were hybridized with two piece of BioDoor 4096 double dot rat whole gene chip. Fluorescence signals were scanned by Scan Array 4000 laser scanner . The difference of gene expression profile was screened and further analyzed by hnagene 3.0 software through the digital computer. The changes in gene expression were further conformed by RT - PCR. The significance of the changes of gene expression profiles in the cochlear of B/A ＆ C/B were analyzed. Results The expression of 227 genes was up - regulated and 128 genes was down - regulated in the cochlea of fortified iron nutrition rats compare with iron deficiency hearing loss rots. Gene expression profile changed significantly in the cochlea of Wistar rats of iron deficiency hearing loss after fortified iron nutrition. The differential expression of genes might be not related to actin. Conclusion Although iron dificiency is responsible for change of expression of genes in membranous cochlea, including actin gene and its related protein. The fortification of iron mutrition can produ

关 键 词：铁缺乏 基因芯片 基因表达 听力损失 肌动蛋白 

分 类 号：R764.5[医药卫生—耳鼻咽喉科]