南极磷虾油对小鼠力竭运动后骨骼肌质膜修复的影响

目的：研究补充南极磷虾油(krill oil,KO)对小鼠一次性力竭运动后骨骼肌质膜损伤和功能恢复的影响，探讨补充南极磷虾油促进骨骼肌质膜损伤修复的可能机制。方法：选取8周龄雄性C57小鼠60只，随机分为豆油对照(bean oil control,BOC)组、豆油运动(bean oil exercise,BOE)组、磷虾油对照(krill oil control,KOC)组和磷虾油运动(krill oil exercise,KOE)组，KO组连续灌胃4周200 mg/(kg m_b·d)磷虾油，豆油组进行等体积豆油灌胃。干预4周后，运动组进行一次性力竭跑台运动，每组6只小鼠在力竭运动后即刻(0 h)、2、6、24、48、72 h进行抓力测试，其余小鼠于运动后2 h取材。比色法检测小鼠血清肌酸激酶(creatine kinase,CK)、乳酸脱氢酶(lactate dehydrogenase,LDH)活力；冰冻切片并采用伊文氏蓝(Evan’s blue dye,EBD)染色法检测小鼠股四头肌质膜完整性；液相色谱-质谱法检测小鼠股四头肌质膜脂肪酸成分；荧光偏振法检测小鼠...

Effect of Antarctic Krill Oil Supplementation on Skeletal Muscle Plasma Membrane Repair in Mice after Exhaustive Exercise

Objective: To investigate the effects of supplementation of Antarctic krill oil (KO) on muscle plasma membrane injury and functional recovery in mice after exhaustive exercise, and to explore the possible mechanism by which KO supplementation promotes muscle plasma membrane injury repair. Methods: Sixty male C57 mice aged eight weeks were randomly divided into a soybean oil control group (BOC), a soybean oil plus exercise group (BOE), a krill oil control group (KOC) and a krill oil plus exercise group (KOE). The mice in the KO groups were intragastrically adminsitered with 200 mg/(kg mb·d) of KO for four weeks, and those in the BO groups were given an equal amount of soybean oil. Thereafter, the mice in the exercise groups were subjected to one-time exhaustive treadmill exercise. Six mice in each group were tested for grasping force immediately (0 h), 6, 24, 48 and 72 h after exhaustive exercise, and the rest were sacrificed 2 h after exhaustive exercise. The activities of serum creatine kinase (CK) and lactate dehydrogenase (LDH) were measured by colorimetric assays. The integrity of mouse quadriceps muscle plasma membrane was detected by Evan’s blue dye (EBD) staining. The fatty acid composition of mouse quadriceps muscle plasma membrane was detected by liquid chromatography-mass spectrometry (LC-MS). The fluorescence polarization degree, microviscosity and fluidity of mouse quadriceps muscle plasma membrane were measured by fluorescence polarization method. Result: 1) After four and three weeks of intervention, the body mass of mice in the KO groups was significantly lower than that of mice in the BO groups (P < 0.05). 2) The exhaustive exercise time of mice in the KOE group was significantly longer than that in the BOE group (P < 0.01), and the grasping force of limbs in mice in the KOE group was significantly higher than that in BOE group at 2, 6, 24 and 48 h after exhaustive exercise (P < 0.05). 3) The serum activity of CK and LDH in mice in the KOE group was significantly lower than that in the BOE group (P < 0.01 and 0.05, respectively). 4) The area of EBD positive muscle fibers in mic from the KOE group was significantly smaller than that in mice from the BOE group (P < 0.05). 5). Compared with the BOC group, the concentration of the unsaturated fatty acid C18:3 in skeletal muscle plasma membrane was significantly decreased in the BOE group (P < 0.05). Compared with the KOC group, the concentrations of the saturated fatty acids C9:0, C10:0, C12:0, C18:0 and C20:0 and the concnentration of the unsaturated fatty acid C20:2 in skeletal muscle plasma membrane were significantly decreased in the KOE group (P < 0.05). The concentrations of the unsaturated fatty acids C22:5, C22:6 (DHA) and C24:5 in skeletal muscle plasma membrane were significantly higher in the KOE group than in the BOE group (P < 0.05). 6) Compared with the BOC group, the fluidity of skeletal muscle plasma membrane in the BOE group was significantly increased (P < 0.05), while the fluidity of skeletal muscle plasma membrane in the KOE group was significantly higher than that in the BOE group (P < 0.01). Conclusion: KO supplementation for four weeks can improve exhaustive exercise performance in mice, enhance the fluidity of skeletal muscle plasma membrane, accelerate the repair of skeletal muscle plasma membrane after exhaustive exercise, and promote the recovery of skeletal muscle function during delayed onset muscle soreness.