4周红景天、红景天苷灌胃对小鼠骨骼肌纤维类型的影响及机制

Effect and Mechanism of Four Weeks Rhodiola or Salidroside Intragastric Gavage on Skeletal Muscle Fiber Type in Mice

目的:为了研究红景天、红景天苷对小鼠不同肌肉骨骼肌纤维类型的影响,进一步探讨作用机制。方法:将30只筛选得出的小鼠按体重和耐力分为对照组、红景天组和红景天苷组,对其进行4周灌胃。检测腓肠肌、比目鱼肌、跖肌中Troponin I-SS(TnI SS)、Troponin I-FS(TnI FS)、Smad3和p-Smad3(Ser423/425)的表达,分析肌纤维类型的变化。结果:各组小鼠体重与腓肠肌、比目鱼肌、跖肌湿重无明显差异。与对照组相比,红景天组和红景天苷组小鼠腓肠肌中TnI SS表达明显增加,且红景天苷组促进表达效果优于红景天组,对TnI FS的表达无明显影响。对照组、红景天组和红景天苷组对Smad3的影响无明显规律性,但红景天组和红景天苷组可有效抑制腓肠肌和比目鱼肌中关键磷酸化因子p-Smad3(Ser423/425)表达。结论:4周红景天和红景天苷灌胃可增加慢肌纤维表达,促进快肌纤维向慢肌纤维转化。灌药对于p-Smad3(Ser423/425)表达的抑制,可能为肌纤维类型转化的机制之一,需运用转染等方法进一步研究机制。

Objective ： This paper aims to explore the effect of rhodiola or salidroside on muscle fiber type in mice, and to detect its mechanism. Methods： Thirty C57BL/6 mice were divided into control, rhodiola, and salidroside groups according to their weight and exercise endurance, and they had been undertaken intragastric gavage for four weeks. The expressions of Troponin I-SS （TnI SS）, Troponin I-FS （TnI FS）, Smad3, and p-Smad3 （Ser423/425） in gastrocnemius, soleus, and plantaris were tested, and the change of muscle fiber type was analyzed. Results ： The weight and muscle weight of gastrocnemius, soleus, and plantaris had no difference among three groups. Compared with control group, the expression of TnI SS of Gastrocnemius in rhodiola and salidroside groups increased significantly,and it was higher in salidroside group than in rhodiola group. Expression of TnI FS didn＇t change in three groups. The expression of p-Smas3 （ Ser423/425）, a key factor of phosphorylation, of gastrocnemius and soleus muscles in rhodiola and salidroside groups decreased significantly although expression of Smad3 didn＇t change in three groups. Conclusion： Four weeks rhodiola, salidroside intragastric gavage can increase type 1 muscle fibers, and promote type Ⅱ muscle fibers transforming to type Ⅰ muscle fibers. The decrease of p-Smad3 （ Ser423/425 ） after four weeks intragastric garage may be one mechanism of muscle fiber type transformation, but it still needs further transfection research.