【摘要】 目的:采用规律有氧运动干预不同年龄大鼠,基于mi RNA表达谱芯片技术,旨在寻找运动适应性作用对神经退行性病变早期作用的靶标,挖掘关键的可解释运动适应性作用机理的靶标基因的生物功能。方法:选取SPF级健康雄性3月龄(青年,n=20)、13月龄(中年,n=24)和22月龄(老年,n=24)SD大鼠,每个年龄组大鼠按体重随机分为青年对照组(Y-SED,n=10)、青年运动组(Y-EX,n=10),中年对照组(M-SED,n=12)、中年运动组(M-EX,n=12),老年对照组(O-SED,n=12)和老年运动组(O-EX,n=12)。三组对照组安静饲养;三组运动组进行10周递增负荷中等强度的规律有氧跑台运动。每周进行体重监控;采用HE染色观察大鼠脑纹状体形态学变化;采用mi RNA微阵列芯片mi RCURYTM LNA Array(v.18.0)等方法分析miRNAs差异表达谱,使用q RT-PCR等对筛选重要差异mi RNA及其相关通路的mRNA表达进行验证与研究。结果:大鼠纹状体的形态学变化明显呈现增龄性变化,实施规律有氧运动后,各年龄组相应地出现线团状的基质部分明显紧凑,之间间隙非常紧密,显微镜下观察细胞核排列有序,数量明显增加。mi RNA微阵列芯片数据结果显示,发生2倍及以上变化差异的miRNAs有26个,经生物信息学分析,最终筛查出规律有氧运动上调mi RNA207和下调mi RNA542的表达,mi RNA207和mi RNA542所作用的下游基因PI3K、Akt和m TOR mRNA表达呈现增龄性下调,与对照组M-SED和O-SED相比较,M-EX和O-EX组PI3K、Akt和m TOR mRNA表达上调(P<0.05,P<0.01)。Vdac1 mRNA呈现增龄性上升趋势,与各年龄安静组相比较,运动组Ca MKIIα和Vdac1 mRNA表达上调显著(P<0.05)。结论:规律有氧运动通过上调mi RNA207和下调mi RNA542的表达而激活大鼠纹状体的PI3K/Akt/m TOR和Ca MKIIα信号通路共同参与调控纹状体的生物学功能和改善神经老化。更多还原

【Abstract】 Objective To explore the new targets of the impact of exercise on the striatal in the early neurodegeneration among rats of different ages with regular aerobic exercise by means of the miRNA expression profile chip technology,and explain the key biochemical and molecular regulation mechanism of the new target genes. Methods Three,13 and 22-month-old specific pathogen free(SPF)male Sprague-Dawley Rat(SD) rats were randomly divided into a young(Y-SED,n=10),a middle-aged(M-SED,n=10) and an old-aged(O-SED,n=12) sedentary control group,and the corresponding Y-EX(n=10),M-EX(n=10) and O-EX(n=12) in the aerobic exercise group. The rats in thesedentary control groups didn’t exercise,while those in the aerobic exercise groups underwent a 10-week regular moderate-intensity aerobic exercise on treadmill. The rats’ body weight was measured ev-ery week. HE staining was used to present the morphological changes in the striatum. The mi RNA microarray of mi RNA mi RCURYTM LNA Array(v.18.0)(Exiqon,Danish) was employed to analyze theexpression profile of miRNAs.The q RT-PCR was performed to screen and to verify the related signalpathways for the biochemical mechanisms. Results The morphology of the rats’ striatum changed clearly with ages. The nuclei in the striatum were arranged orderly and the number of nuclei increased sig-nificantly in each group undergoing regular aerobic exercise. mi RNA microarray data showed that 26 miRNAs increased to no less than twice of the original level. The expression of mi RNA207 was foundup-regulated while that of mi RNA542 was down-regulated after regular aerobic exercise through screen-ing the bioinformatics of mi RNA. The expression of PI3 K,Akt and m TOR mRNA,downstream genesof mi RNA207 and mi RNA542,was also found down-regulated with the increase of age. However,com-pared with the sedentary groups,the expression of PI3 K,Akt and m TOR was higher in the exercisegroups. The Vdac1 mRNA was observed an increasing tendency with age. Compared with all the seden-tary groups,significant upregulation was observed in the expression of Ca MKIIα and Vdac1 in the aerobic exercise groups. Conclusion Regular aerobic exercise can regulate the biological function of rats’ striatum and alleviate the aging process through upregulating the expression of mi RNA207 and downregulating that of mi RNA542 to activate the PI3K/Akt/m TOR and Ca MKIIα signaling pathway.更多还原