不同年龄阶段Duchenne型肌营养不良患儿肌细胞膜上DGC关联复合物蛋白的表达

Expression of dystrophin associated glycoprotein complex in Duchenne muscular dystrophy at different age groups

目的研究不同年龄阶段Duchenne型肌营养不良患儿肌细胞膜上DGC关联复合物蛋白的表达。方法将24例已确诊的Duchenne型肌营养不良患儿根据儿童发育年龄分成3组,0.5～3岁为幼儿期组,～6岁为学龄前期组,～13岁为学龄期组。利用免疫组织化学方法对肌细胞膜上与抗肌萎缩蛋白(dystrophin)组成相关DGC复合体的蛋白进行分析。结果dystrophin蛋白的缺失可引起不同年龄阶段的肌细胞膜上α-SG、β-SG、γ-SG、δ-SG、β-DG和dysferlin不同程度的缺乏或完全缺乏;肌细胞膜上的nNOS蛋白在3组中完全缺乏,而caveolin-3蛋白表达增加。结论与dystrophin组成相关DGC复合体的蛋白在不同年龄阶段Duchenne型肌营养不良患儿均呈现不同程度的缺乏或完全缺乏,这些蛋白的缺乏可能发生在胚胎时期,而caveolin-3蛋白表达增高与肌纤维再生过程有关。

Objective To analyze the expression of dystrophin associated glycoprotein complex （DGC） in Duchnne muscular dystrophy （DMD） in different age groups. Methods The confirmed 24 DMD patients were divided into 3 groups according to their chronological age （children whose age between l to 3 were assigned to early childhood group; children whose age between 3 to 6 were assigned to preschool group; children whose age between 6 to 13 were assigned to school-age group）. Several proteins from sarcolemmal muscle membrane were analyzed by immunohistochemistry. Results The primary loss of dystrophin may lead to a secondary or completely deficiency of α-SG. β-SG γ-SG. δ-SG, δ-DG and dysferlin from sarcolemmal muscle membrane in different age groups. The expression of nNOS is completely deficient in the 3 groups, while the expression of caveolin-3 increased. Conclusions The expression of dystrophin related DGC proteins from DMD patients in different age groups showed diversed degrees of deficiency or complete deficiency. The deficiency of these proteins may occur during the embryonic period, while the increased expression of caveolin-3 may have a relation with the regeneration of skeletal muscle fibers.