Paulsen Gøran, Vissing Kristian, Kalhovde John Magne, Ugelstad Ingrid, Bayer Monika Lucia, Kadi Fawzi, Schjerling Peter, Hallén Jostein, Raastad Truls
Norwegian School of Sport Sciences, P.O. Box 4014 U.S., N-0806 Oslo, Norway.
Am J Physiol Regul Integr Comp Physiol. 2007 Aug;293(2):R844-53. doi: 10.1152/ajpregu.00677.2006. Epub 2007 May 23.
In this study the stress protein response to unaccustomed maximal eccentric exercise in humans was investigated. Eleven healthy males performed 300 maximal eccentric actions with the quadriceps muscle. Biopsies from vastus lateralis were collected at 30 min and 4, 8, 24, 96, and 168 h after exercise. Cellular regulation and localization of heat shock protein (HSP) 27, alpha B-crystallin, and HSP70 were analyzed by immunohistochemistry, ELISA technique, and Western blotting. Additionally, mRNA levels of HSP27, alpha B-crystallin, and HSP70 were quantified by Northern blotting. After exercise (30 min), 81 +/- 8% of the myofibers showed strong HSP27 staining (P < 0.01) that gradually decreased during the following week. alpha B-Crystallin mimicked the changes observed in HSP27. After exercise (30 min), the ELISA analysis showed a 49 +/- 13% reduction of the HSP27 level in the cytosolic fraction (P < 0.01), whereas Western blotting revealed a 15-fold increase of the HSP27 level in the myofibrillar fraction (P < 0.01). The cytosolic HSP70 level increased to 203 +/- 37% of the control level 24 h after exercise (P < 0.05). After 4 days, myofibrillar-bound HSP70 had increased approximately 10-fold (P < 0.01) and was accompanied by strong staining on cross sections. mRNA levels of HSP27, alpha B-crystallin, and HSP70 were all elevated the first day after exercise (P < 0.01); HSP70 mRNA showed the largest increase (20-fold at 8 h). HSP27 and alpha B-crystallin seemed to respond immediately to maximal eccentric exercise by binding to cytoskeletal/myofibrillar proteins, probably to function as stabilizers of disrupted myofibrillar structures. Later, mRNA and total HSP protein levels, especially HSP70, increased, indicating that HSPs play a role in skeletal muscle recovery and remodeling/adaptation processes to high-force exercise.
在本研究中，对人体不习惯的最大离心运动的应激蛋白反应进行了调查。11名健康男性用股四头肌进行了300次最大离心动作。在运动后30分钟以及4、8、24、96和168小时采集股外侧肌活检样本。通过免疫组织化学、酶联免疫吸附测定（ELISA）技术和蛋白质印迹法分析热休克蛋白（HSP）27、αB-晶状体蛋白和HSP70的细胞调节及定位。此外，通过Northern印迹法定量HSP27、αB-晶状体蛋白和HSP70的mRNA水平。运动后（30分钟），81±8%的肌纤维显示出强烈的HSP27染色（P<0.01），在接下来的一周内逐渐减少。αB-晶状体蛋白呈现出与HSP27类似的变化。运动后（30分钟），ELISA分析显示胞质部分的HSP27水平降低了49±13%（P<0.01），而蛋白质印迹法显示肌原纤维部分的HSP27水平增加了15倍（P<0.01）。运动后24小时，胞质HSP70水平增加到对照水平的203±37%（P<0.05）。4天后，与肌原纤维结合的HSP70增加了约10倍（P<0.01），并且在横切面上伴有强烈染色。运动后第一天，HSP27、αB-晶状体蛋白和HSP70的mRNA水平均升高（P<0.01）；HSP70 mRNA的增加最为显著（8小时时增加20倍）。HSP27和αB-晶状体蛋白似乎通过与细胞骨架/肌原纤维蛋白结合，对最大离心运动立即做出反应，可能起到破坏的肌原纤维结构稳定剂的作用。随后，mRNA和总的HSP蛋白水平，尤其是HSP70增加，表明HSP在骨骼肌恢复以及对高强度运动的重塑/适应过程中发挥作用。
