亚精胺对小鼠骨骼肌自由基代谢影响及抗疲劳的效果研究

目的：研究亚精胺（spermidine，SPD）对骨骼肌自由基代谢的影响以及抗疲劳作用。方法：实验分为生理盐水组、SPD低剂量组（0.5 mmol/（kg·d））、中剂量组（1.0 mmol/（kg·d））、高剂量组（1.5 mmol/（kg·d））以及西洋参口服液阳性对照组（总皂苷30 mg/（kg·d）），每周灌胃6 d共30 d，每次灌胃前称量小鼠体质量调整灌胃溶液量，灌胃期间进行每天45 min无负重游泳训练。各组随机选取10 只小鼠测试力竭游泳时间；各组剩余10 只负重游泳30 min，休息30 min后取材，检测血清肌酸激酶（creatine kinase，CK）、骨骼肌谷胱甘肽-过氧化物酶（glutathione peroxidase，GSH-Px）、总超氧化物歧化酶（total-superoxide dismutase，T-SOD）、琥珀酸脱氢酶（succinate dehydrogenase，SDH）活性和骨骼肌丙二醛（malondialdehyde，MDA）含量。结果：与生理盐水组比较，SPD能显著延长小鼠力竭游泳时间（P＜0.05）；低、中剂量组骨骼肌中GSH-Px、T-SOD、SDH酶活性显著提高（P＜0.05），MDA含量显著降低（P＜0.05）；SPD组与西洋参组比较，低、中剂量抗疲劳效果有非常显著性（P＜0.05）差异，高剂量抗疲劳效果略优（P＞0.05）。结论：0.5～1.0 mmol/（kg·d） SPD可以增加抗氧化酶的活性，减少自由基的积累，提高骨骼肌细胞膜代谢能力和抗损伤能力，显著推迟小鼠疲劳发生。

Influence of Spermidine on Free Radical Metabolism in Skeletal Muscle and Its Anti-fatigue Effect in Mice

Objective: To explore the influence of spermidine (SPD) on the metabolism of free radicals in skeletal muscle and its
anti-fatigue effect in mice. Methods: Mice were divided into negative control (normal saline), low-, middle- and high-dose SPD (0.5,
1.0 and 1.5 mmol/(kg·d), respectively) and positive control groups (American ginseng oral liquid, total saponin 30 mg/(kg·d)). The
administration period was 6 days per week for 5 weeks. Before each administration, body weight was measured based on which
the volume of administration was determined. The mice were subjected to swimming without weight loading for 45 min each
day during the administration period. Ten mice were sampled randomly from each group to examine the exhaustive swimming
time. The other 10 mice in each group with 30 min swimming with loading were dissected after 30 min recovery to determine the
activities of serum creatine kinase (CK) and skeletal muscle glutathione peroxidase (GSH-Px), total-superoxide dismutase (T-SOD)
and succinate dehydrogenase (SDH) and skeletal muscle MDA content. Results: Compared with the negative control group, SPD
could prolong the exhaustive swimming time of mice (P ＜ 0.05); The activities of GSH-Px, T-SOD and SDH were improved in
skeletal muscle (P ＜ 0.05). Furthermore, the content of MDA was reduced (P ＜ 0.05). On the other hand, compared with the
positive control group, low- and medium-dose SPD showed a significant difference in anti-fatigue effect (P ＜ 0.05), and high-dose
SPD revealed slightly better anti-fatigue effect than American ginseng although no significant difference was observed (P ＞ 0.05).
Conclusion: SPD at a dose of 0.5－1.0 mmol/(kg·d) can increase the activity of antioxidant enzymes and reduce the accumulation
of free radicals. Meanwhile, SPD can improve the metabolism of skeletal muscle and prevent injuries, and delay the onset of
exercise fatigue in mice significantly. Therefore, SPD is an excellent anti-fatigue tonic.