过度训练对大鼠骨骼肌炎性因子和氧化应激相关基因表达的影响

目的:了解过度训练对大鼠骨骼肌炎性因子和氧化应激相关基因表达的影响。方法:8周龄健康雄性Wistar大鼠26只,随机分为安静对照组(C,n=10)、过度训练后36 h取材组(E1,n=8)和过度训练后7天取材组(E2,n=8)。过度训练组进行11周递增负荷跑台训练。断头处死大鼠并分离右后肢腓肠肌,采用荧光定量PCR技术测定腓肠肌TNF-α、IL-1β、IL-10、RANTES、NADPH氧化酶催化亚基(gp91phox)、PKC-δ基因表达。结果:C组、E1组和E2组促炎因子TNF-α和IL-1βmRNA表达量三组之间无显著差异(P>0.05);E1组和E2组抑炎因子IL-10 mRNA表达量显著低于C组(P<0.05,P<0.01);E1组和E2组趋化因子RANTES mRNA表达量显著高于C组(P<0.05)。相关分析显示,IL-10与RANTES呈负相关(r=-0.56,P<0.05)。C组、E1组和E2组gp91phox mRNA表达量三组之间差异无统计学意义(P>0.05);E1组PKC-δmRNA表达量显著高于C组(P<0.05),E2组PKC-δmRNA表达量相对E1组降低,仍高于C组水平,但无统计学意义。结论:过度训练对大鼠骨骼肌TNF-α和IL-1β表达无显著影响,但可显著上调RANTES基因表达和下调IL-10基因表达;过度训练可上调骨骼肌氧化应激相关基因表达。

Effects of Overtraining on the Gene Expression of Inflammatory Cytokines and Oxidative Stress in Rat Skeletal Muscle

Objective To investigate the effect of overtraining on the inflammation and oxidative stress of skeletal muscle.Methods Twenty six male Wister rats were randomly divided into 3 groups: sedentary group(C,n = 10),two overtraining groups,which were sampled at 36h(E1,n = 8)and 7 day(E2,n = 8)receptively,after the last training.Rats in overtraining group were trained on standard treadmill with an increasing load for 11 weeks.Gastrocnemius muscle of right hind limb was isolated after all rats were sacrificed by decapitation.The mRNA expression of TNF-α,IL-1β,IL-10,RANTES,gp91phox(a subunit of NADPH oxidase)and PKC-δ were detected by real time-PCR.Results The expression of TNF-α and IL-1β showed no significant differences among group C,group E1 and group E2.The IL-10 mRNA level in group E1 and group E2 was significant lower than in group C(P < 0.05,P < 0.01,respectively).Group E1 and group E2 showed a significant increase in RANTES gene expression when compared with group C(P < 0.05).Analysis showed that there was negative correlation between IL-10 and RANTES,and the Pearson correlation was-0.56(P < 0.05).The gp91phox mRNA level had no significant difference among group C,group E1 and group E2.The expression of PKC-δ in group E1 was significant higher than in group C(P < 0.05).Conclusion Overtraining has no significant effect on TNF-α and IL-1β mRNA levels in skeletal muscle,however,it induces up-regulation of RANTES mRNA and down-regulation of IL-10 mRNA.In addition,overtraining induces up-regulation of oxidative-stress gene in skeletal muscle.