白藜芦醇对离心运动后骨骼肌微损伤的修复

背景：白藜芦醇是一种天然的抗氧化剂和自由基廓清剂，具有清除自由基、减轻脂质过氧化等重要药理作用，目前有关白藜芦醇在减轻骨骼肌损伤、促进损伤修复方面的研究尚不多见。 目的：观察白藜芦醇对离心运动后骨骼肌超微结构损伤、血清丙二醛和肌细胞浆Ca2+浓度的影响。 设计、时间及地点：对照观察动物实验，于2007-08/2008-06在南方医科大学完成。 材料：成年雄性SD大鼠72只，实验室适应性喂养3 d后随机分为蒸馏水组(n=40)、白藜芦醇组(n=32)。白藜芦醇制剂购自湖南省洪江华光生物有限公司。 方法：白藜芦醇组大鼠每日腹腔注射1次白藜芦醇制剂60 mg/kg，蒸馏水组大鼠腹腔注射等量蒸馏水，连续2周。2周后，将大鼠在动物跑台上进行一次性下坡跑运动，速度为16 m/min，下坡坡度为16°，5 min运动，2 min休息，总运动时间为120 min。运动过程中采用人工驱赶和声刺激，不使用电刺激。 主要观察指标：于运动前、运动后即刻、运动后24，48，72 h电镜下观察比目鱼肌纤维Z线，TAB法测定血清丙二醛和流式细胞仪检测肌细胞浆Ca2+浓度。 结果：与蒸馏水组比较，白藜芦醇组镜下肌纤维损伤程度减轻，骨骼肌细胞Z线异常百分率在运动后即刻、运动后24，48，72 h比蒸馏水组分别降低了50.34%，52.67%，52.65%和53.26%(P < 0.05)，离心运动引起的血清丙二醛升高程度分别下降了27.7%，29.56%，34.38%和27.79%(P < 0.05)，胞浆Ca2+浓度分别降低了27.53%，25.84%，22.14%和11.62% (P < 0.05)。 结论：白藜芦醇可降低离心运动后血清丙二醛浓度和肌细胞浆Ca2+浓度，减轻运动导致的肌肉损伤。

Effects of resveratrol on the repair of skeletal muscle microdamage after eccentric exercise

BACKGROUND: As a natural antioxidant and free radicals clearer, resveratrol has many important pharmacological effects, such as clearing free radicals and relieving lipid peroxidation. However, studies on its effects on lessening skeletal muscle damage and promoting recovery are still few. OBJECTIVE: To investigate the influence of resveratrol on skeletal muscle ultra-microstructure damage, the serum malonaldehyde (MDA) concentration and the intracellular Ca2+ concentration after eccentric exercise. DESIGN, TIME AND SETTING: A controlled observational animal experiment was carried out in the Southern Medical University from August 2007 to June 2008. MATERIALS: A total of 72 adult male SD rats, which were adaptively fed for 3 days in laboratory, were divided into a distilled water group (n =40) and a resveratrol group (n =32). Resveratrol was purchased from Hunan Huaguang Biological Products Co., Ltd. METHODS: Rats in the resveratrol group were injected intraperitoneally with 60 mg/kg resveratrol preparation once a day and the distilled water group with distilled water of the same dose. After 2 weeks of injection, they were tested by a 120-minute one trial downhill running on the animal treadmill at a speed of 16 m/min and a gradient of 16°, with a 2-minute rest following every 5-minute exercise. In the test, rats were driven to run by human or sound stimulus instead of electrical stimulus. MAIN OUTCOME MEASURES: The soleus muscle fibers Z-band of rats was observed under the electron microscope before exercise, immediately post-exercise, 20, 48 and 72 hours post-exercise respectively. The serum MDA concentration was determined with TAB method. The intracellular Ca2+ concentration was detected by flow cytometry. RESULTS: Compared with the distilled water group, the muscle fibers damage of rats in the resveratrol group was lessened. According to the detection made immediately post-exercise, 24, 48 and 72 hours post-exercise, Z-band abnormal percentages of skeletal muscles in the resveratrol group decreased by 50.34%, 52.67%, 52.65% and 53.26% respectively (P < 0.05), the serum MDA concentrations decreased by 27.7%, 29.56%, 34.38% and 27.79% respectively (P < 0.05) and the intracellular Ca2+ concentration decreased by 27.53%, 25.84%, 22.14% and 11.62% respectively (P < 0.05), compared with those of the distilled group. CONCLUSION: Resveratrol is effective in lowering the serum MDA and intracellular Ca2+ concentration after eccentric exercise and lessening the excess-induced muscle damage.