摘要
目的:对应用糖皮质激素(glucocorticoid,GC)治疗Duchenne型肌营养不良(Duchenne muscular dystrophy,DMD)的机制进行探讨。方法:应用DMD动物模型mdx小鼠进行实验,将模型组随机分为3组,Mdx模型组(6周龄)、Mdx安慰剂组(12周龄)、Mdx GC治疗组(12周龄),每组8只,另取正常C57小鼠,6周龄和12周龄各8只,作为正常对照组,分别进行悬吊实验,测量时间,观察治疗前后时间变化;测量血清CK值,了解肌肉损伤情况;对所分离的腓肠肌进行HE染色,在电镜下观察病理变化;检测肌肉中Utrophin蛋白表达状况,应用Western blot进行检测,同时获得核因子-κB(nuclear factor-κB,NF-κB)、I-κB、热休克蛋白70(heat shak protein,HSP70)蛋白表达水平,采用独立样本t检验、方差分析(多重比较)和配对t检验统计方法发现与前者关系所在。结果:GC治疗实验动物出现明显变化,与安慰剂相比具有差异明显:(1)Mdx小鼠与治疗前相比肌力明显好转;治疗前悬吊实验时间为(22±11)s,治疗后为(43.8±24.9)s,P<0.001,CK值下降明显,治疗前为(20 230±2 444)U/L,治疗后为(6 457±2 215)U/L,P<0.001;(2)Mdx小鼠腓肠肌电镜下进行细胞学观察,发现较前明显好转;(3)Mdx小鼠肌肉组织中HSP70蛋白表达水平明显增加,OD比值由治疗前0.50±0.09上升至治疗后0.75±0.09,P<0.001,而Utrophin蛋白表达从0.23±0.03上升至0.42±0.08,P=0.003,NF-κB蛋白表达由治疗前0.33±0.04下降至0.26±0.02,P<0.001,治疗前后I-κB蛋白表达由0.21±0.06变至0.18±0.05,P=0.372。结论:应用GC治疗后HSP70表达增强,NF-κB活性下降,Utrophin表达增加,从而使Mdx小鼠的肌肉病变有所延缓,肌力增加。
Objective：To apply glucocorticoid（GC） to treat Duchenne muscular dystrophy（DMD） and to discuss its mechanism.Methods：DMD animal model was used in the experiment.The model group was randomly divided into three subgroups,namely Mdx model group（6-week age）,Mdx placebo group（12-week age）,Mdx GC treatment group（12-week age）,eight rats in each group.Eight normal 6-week age C57 rats and 8 12-week age C57 rats were taken as normal control groups,respectively and suspension experiment was carried out.The time required was measured and the changes of time before and after the treatment were observed.Gastrocnemius was applied to measure serum CK values,and to understand muscle damage;HE staining was carried out on the decomposition of the muscle,to observe the pathological changes under the electron microscope;Western blot was used to test the utrophin protein expression and the NF-kappa B/I-kappa B predominate and HSP70 protein expression.Independent sample t test,variance analysis（multiple comparisons）and matching t test statistics were adopted to found the the relationship between the NFkappa B/I-kappa B predominate and HSP70 protein expression.Results：After GC treatment,obvious changes were observed in the experimental animals than in the placebo with significant differences.（1） The Mdx mice were significantly better after the treatment.In suspension test,the time pre-treatment was（22±11） seconds,while that post-treatment was（43.8±24.9） seconds,P〈0.001.CK decreased significantly,from（20 230 ±2 444） U/L before the treatment to（6 457±2 215）U/L after the treatment,P〈0.001.（2）The cytological observation was performed in the mouse under the gastroenteroscope among Mdx mice,and the findings were significantly improved than before.（3） HSP70 protein expression level increased significantly in the muscle tissue in Mdx mice,the OD ratio increaded from 0.50±0.09 before the treatment to 0.75 ±0.09 after the treatment,P〈0.001,while Utrophin protein expression incr
出处
《重庆医科大学学报》
CSCD
北大核心
2017年第12期1598-1603,共6页
Journal of Chongqing Medical University
基金
重庆市卫生局医学科研资助项目(编号:2012-1-044)
