The Research On The Mechanism Of Exercise-induced Muscle Damage And The Effect Of Taurine And Resveratrol Supplementation

Exercise-induced muscle damage(EIMD)is referred to the micro-damage of skeletal muscle fiber after undergone an unaccustomed high-intensity and/or prolonged exercise.The study observed the effects of taurine and resveratrol supplementation on the exercise-induced muscle damage. Indexes such as serum Creatine Kinase , serum MDA,serum SOD,serum Interleukin-6(IL-6) and cytoplasm [Ca2+]i were selected to compare.The purpose of this study was to explore the mechanism of EIMD further, search for the new index for evaluating EIMD and explore the protective mechanism and meaning of the taurine and the resveratrol. In a word,we hope to establish the foundation through this study for further correlated research on these medicines.104 male SD rats were selected as the study objects and randomly divided into no-exercise control group,eccentric exercise + water group, eccentric exercise plus taurine group and eccentric exercise plus resveratrol group. Each exercise group was divided into four groups by post-exercise 0hour,24hours,48hours and 72hours according to the difference of samples taking. There are 13 groups and each group has 8 rats. Exercise groups rats undertake a Bout of eccentric exercise of 120minutes on the treadmill, which the speed was 16metre every minute, gradient was 16°. Rats were killed respectively according to the groups.The left hind limb soleus muscles were fetched to observe the cell shape under the electron-microscope.Indexes of CK,MDA,SOD,IL-6 and [Ca2+]i were determined at the same time.The control group rats didn't run at the treadmill.Results:(1)The ultra-microstructure of the soleus muscles had unequal damage,and the Z-band of the muscle cell had abnormal change after eccentric exercise. The most obvious change occurred post-exercise 24-48hours. The supply of taurine and resveratrol could obviously lessen these abnormal changes,and the effects of the resveratrol supplementation better than that of taurine supplementation.(2)The serum CK and MDA enhanced after eccentric exercise and reached the peak concentration in 24hours post-exercise, and there was obvious correlation between them.The activity of serum SOD was increased after eccentric exercise,but it's peak concentration appeared at 48 hours post-exercise. The supply of taurine and resveratrol could obviously restrain the increase of serum CK and MDA,and enhance the activity of the serum SOD(P<0.05).(3)The serum IL-6 and the cytoplasm [Ca2+]i enhanced after eccentric exercise at the different phase post-exercise.The peak concentration of these indexes appeared at 48hours post-exercise. The supply of taurine and resveratrol could obviously restrain the increase of serum IL-6 and the cytoplasm [Ca2+]i(P<0.05).(4)Correlation analysis result:the Pearson Correlation between the Z-band abnormal rate and the serum CK,MDA,IL-6,the cytoplasm [Ca2+]i were 0.428,0.542,0.787 and 0.805 separately. The Pearson Correlation between the serum CK and the cytoplasm [Ca2+]i, the serum MDA were 0.452 and 0.927. The Pearson Correlation between the serum IL-6 and the serum MDA, the cytoplasm [Ca2+]i were 0.619 and 0.728.All these data have significance meaning(P<0.05).Conclusion:(1)High intensity eccentric exercise could induce severe delayed onset micro-injuries of skeletal muscle,which included the ultra- microstructure change,the serum indexes changes,and the cytoplasm [Ca2+]i change. The possible reason of EIMD occurrence was complicated, which may include the factors of the mechanical extension,free radical damage and the cytoplasm [Ca2+] overload et al.Of these reasons, cytoplasm [Ca2+] overload is the most important factor related to EIMD.(2)Both the taurine and the resveratrol could restrain EIMD and lessen the damage degree of EIMD.They could obviously lighten the Z-band abnormal rate,the plasma IL-6,the serum CK,MDA and the cytoplasm [Ca2+]i(P<0.05).They could also obviously increase the serum SOD concentration(P<0.05).The effects of the resveratrol supplementation on lessening the degree of EIMD have no different with the Tau supplementation.(3) The plasma IL-6 level significantly elevated after high intensity eccentric exercise. Contrast to serum CK , the plasma IL-6 has closer correlation with the damage degree of the muscle cell ultra- microstructure. The plasma IL-6 could be utilized as one of the indexes to examine EMID.(4)The cytoplasm [Ca2+]i concentration dramatically risen after eccentric exercise. Like plasma IL-6,the cytoplasm [Ca2+]i has close correlation with the damage degree of the muscle cell. The results demonstrate the close relation among the cytoplasm [Ca2+]i,the plasma IL-6 and the muscle damage. As the detection of the cytoplasm [Ca2+]i is complex,the application of this index is restricted to examine EMID.