简介:目的:以骨骼肌卫星细胞NO/HGF/c-Met激活通路为切入点,研究不同低氧训练对骨骼肌蛋白质合成的影响.方法:50只雄性SD大鼠随机平均分为低住安静组(LC)、低住低练组(LL)、高住安静组(HC)、高住低练组(HL)及高住高训低练组(HHL),实验4周后检测股四头肌卫星细胞激活通路中HGF、c-Met、MAPK蛋白表达水平及NO的含量.结果:与其他各组相比,HHL组大鼠股四头肌蛋白质含量显著减少(P<0.05),而其NO水平显著高于LC和LL组(P<0.05),各组HGF及c-Met水平没有显著差异(P>0.05);另外,HHL组MAPK水平显著或极显著低于LC组、LL组及HC组(P<0.05,P<0.01),同时,HL组的MAPK水平也显著低于LL组(P<0.05).结论:高住高练低训可导致骨骼肌蛋白的丢失,其机制与肌卫星细胞NO/HGF/c-Met激活通路中HGF分泌减少及MAPK活性下降有关.
简介:Background:Overweightandobesityhasbecomeaseriouspublichealthprobleminmanypartsoftheworld.Studiessuggestthatmakingsmallchangesindailyactivitylevelssuchas"breaking-up"sedentarytime(i.e.,standing)mayhelpmitigatethehealthrisksofsedentarybehavior.Theaimofthepresentstudywastoexaminetimespentinstanding(determinedbycountthreshold),lying,andsittingpostures(determinedbyinclinometerfunction)viatheActiGraphGT3Xamongsedentaryadultswithdifferingweightstatusbasedonbodymassindex(BMI)categories.Methods:Participantsincluded22sedentaryadults(14men,8women;meanage26.5±4.1years).Allsubjectscompletedtheself-reportInternationalPhysicalActivityQuestionnairetodeterminetimespentsittingovertheprevious7days.Participantswereincludediftheyspentsevenormorehourssittingperday.PosturesweredeterminedwiththeActiGraphGT3Xinclinometerfunction.Participantswereinstructedtoweartheaccelerometerfor7consecutivedays(24haday).BMIwascategorizedas:18.5to<25kg/m2asnormal,25to<30kg/m2asoverweight,and≥30kg/m2asobese.Results:Participantsinthenormalweight(n=10)andoverweight(n=6)groupsspentsignificantlymoretimestanding(afteradjustmentformoderate-to-vigorousintensityphysicalactivityandwear-time)(6.7hand7.3hrespectively)andlesstimesitting(7.1hand6.9hrespectively)thanthoseinobese(n=6)categories(5.5hand8.0hrespectively)afteradjustmentforwear-time(p<0.001).Therewerenosignificantdifferencesinstandingandsittingtimebetweennormalweightandoverweightgroups(p=0.051andp=0.670respectively).Differenceswerenotsignificantamonggroupsforlyingtime(p=0.55).Conclusion:Thisstudydescribedposturalallocationsstanding,lying,andsittingamongnormalweight,overweight,andobesesedentaryadults.Theresultsprovideadditionalevidencefortheuseofincreasingstandingtimeinobesitypreventionstrategies.
简介:目的:探讨4周中等强度跑台运动对慢性不可预知性应激致抑郁大鼠开场实验及空间学习记忆能力、血清皮质醇和前额叶皮质(PFC)自由基代谢及c-fos表达的影响。方法:将30只大鼠随机分为对照组、应激模型组及应激运动组3组,每组10只。应激模型组及应激运动组大鼠每日进行慢性不可预知性应激1次,连续28天,同时应激运动组大鼠进行4周跑台运动。跑台运动结束后检测所有大鼠血清皮质醇水平及PF区自由基含量,运用开场实验测试大鼠主动活动能力及探索行为,Y迷宫实验测试大鼠空间学习记忆能力,采用免疫组织化学结合图像半定量方法对PF区c-fos神经元的数量、面积及灰度进行测量和分析。结果:(1)与应激模型组比较,应激运动组大鼠穿越格数、直立次数及修饰次数显著增多(P〈0.01,P〈0.05),中央格停留时间缩短(P〈0.05),粪便颗粒减少(P〈0.05);(2)与应激模型组比较,应激运动组大鼠血清皮质醇水平下降(P〈0.05),PF区SOD活性增强(P〈0.05),MDA含量下降(P〈0.05);应激运动组大鼠在Y迷宫训练中达到标准时训练时间缩短,电击次数减少(P〈0.05),Y迷宫记忆能力测试中,应激运动组大鼠错误次数少于应激模型组;(3)与应激模型组比较,应激运动组大鼠PFC区原癌基因c-fos免疫阳性神经元面积及数量表达均增加(P〈0.05),灰度值虽降低,但没有显著差异(P〉0.05)。结论:长期跑台运动可提高抑郁大鼠的学习记忆能力,可能与跑台运动降低抑郁大鼠血清皮质醇水平、增强脑抗氧化能力及上调前额叶皮质c-fos的表达有关。