目的:探讨Myostatin重组蛋白疫苗(His-Ms)对小鼠骨骼肌质量和力量的影响及其相关机制。方法:实验动物分为正常对照组和His-Ms组,每组10只。采用基因工程技术表达并纯化的Myostatin无活性蛋白作为疫苗,按100μg/只剂量对His-Ms组小鼠进行免疫,每隔14 d免疫1次,免疫4次,共62 d。在His-Ms组小鼠进行免疫时,正常对照组腹腔注射相等体积生理盐水。最后一次免疫后20 d对照组和His-Ms组动物取血样和组织样本,检测血清Myostatin抗体水平及胆固醇(CHO)、甘油三脂(TG)、尿素氮(BUN)、血糖(GLU)、肌酸激酶(CK)等血液指标,检测骨骼肌质量和细胞形态等指标。结果:利用高纯度His-Ms重组蛋白作为疫苗免疫小鼠,可诱导小鼠产生特异性抗体,平均抗体滴度在2×102以上。血清中CHO、TG、BUN、GLU和CK等指标两组小鼠间无显著性差别。与正常对照组比较,His-Ms组免疫小鼠体重平均增加了3.6%;股四头肌、腓肠肌和胸大肌重量分别增加了11.2%、3.2%和15.8%,股四头肌横断面积增加了5.6%,而每束肌纤维平均细胞数两组之间无明显差别。His-Ms组免疫小鼠前肢抓力与正常对照组比较平均增加了26.6%,增加显著(P〈0.05)。结论:Myostatin重组蛋白疫苗免疫使小鼠体重和肌肉质量不同程度增加,抓力明显增强。
Aim The purpose of the study is to investigate the effects of myostatin recombinant protein vaccine(MRPC)on the skeletal muscle mass and strength of mice.Methods Two groups of mice(His-Ms group and control group) were allocated.The mice in His-Ms group were immunized with inactive myostatin recombinant protein(100μg per mouse,4 vaccinations within 62 days,with an interval of 14 days).The mice in control group were intraperitoneally injected with the same amount of saline at the same time.20 days after the last immunization,the levels of anti-myostatin antibody,serum cholesterin(CHO),triglyceride(TG),blood urea nitrogen(BUN),glucose(GLU)and creatine kinase(CK),as well as the muscle strength(through rope grip test)in two groups were measured.The muscle mass and muscle morphology in two groups were also determined.Results The average specific antibody titer induced by MRPC was above 2×102.There were no differences in the levels of CHO,TG,BUN,GLU and CK between the two groups.The average body weight in His-Ms group increased by 3.6% comparing to the control group.The average mass of quadriceps,gastrocnemius and pectoralis increased by 11.2%,3.2% and 15.8% respectively in His-Ms group,and they were greater than those in control group.Cross-sectional area of whole quadriceps in His-Ms group increased by 5.6% as compared with that in control group,while there was no significant difference in the average fiber number between the two groups.Improved performance of rope grip test by 26.6% in His-Ms group was more significantly than that in control group(P 0.05).Conclusion The body weight,muscle mass,especially the muscle strength of mice immunized with MRPC increased significantly.