AS160与TBC1D1:胰岛素和运动/骨骼肌收缩诱导葡萄糖转运的汇聚点

运动和胰岛素是诱导骨骼肌葡萄糖转运的两种重要生理因素,两者均能通过不同的信号转导通路诱导GLUT4从细胞内转位到细胞膜表面,从而调控骨骼肌的葡萄糖转运。研究表明,TBC1家族结构域家族成员蛋白激酶B蛋白底物160KDa（AS160/TBC1D4）和TBC1D1这两种同源蛋白均可在运动或胰岛素诱导下发生磷酸化,两者可能是运动和胰岛素调控骨骼肌葡萄糖转运信号通路的关键汇聚点。综述AS160与TBC1D1在胰岛素诱导骨骼肌葡萄糖转运中的不同作用以及运动/骨骼肌收缩对其的影响及其机制,以期深入了解运动如何改善胰岛素敏感性、为更科学的运动处方及其他干预措施的研发提供有价值的理论支持。     

运动对GLUT4影响的研究进展

葡萄糖跨膜转运是机体利用葡萄糖的首要步骤。葡萄糖载体(GLUT)是细胞膜上介导葡萄糖跨膜转运的蛋白质,它们对机体的葡萄糖利用有重要意义。运动可有效增加外周组织(主要为骨骼肌和脂肪组织)细胞膜葡萄糖载体4(GLUT4)的数量,使细胞内GLUT4的囊泡数量增多,GLUT4mRNA的表达增强,有效地加快血糖的转移、吸收和利用,解除外周组织胰岛素抵抗,调节血糖平衡,对糖尿病人的治疗有积极的作用和意义。     

运动性贫血大鼠红细胞膜功能变化与运动方式的关系

研究目的:研究红细胞膜功能改变与运动方式的关系。研究方法:通过跑台运动和游泳运动两种方式建立运动性贫血动物模型,测定红细胞膜磷脂酰丝氨酸外翻率,带3蛋白,葡萄糖载体蛋白-1转运功能,钠钾ATP酶活性。研究结果:两种运动方式诱导的运动性贫血时红细胞膜磷脂酰丝氨酸外翻率,带3蛋白阴离子转运蛋白功能、葡萄糖载体蛋白转运葡萄糖功能,钠钾ATP酶活性变化没有显著差异。结论:运动性贫血红细胞膜功能的改变与不同运动方式无关。     

重复运动对骨骼肌糖转运能力的调节作用

长时间的胰岛素缺乏,既会使脂肪细胞内胰岛素依赖性2-脱氧葡萄糖的转运降低,也会使骨骼肌内胰岛素和肌收缩刺激作用依赖性3-甲基葡萄糖的转运降低。胰岛素对脂肪细胞和骨骼肌细胞内糖转运载体分子具有长期的调节作用,而肌肉收缩刺激能产生一种不同于胰岛素的糖转运调节作用(Wallberg-Henr-     

运动对p38MAPK的影响

运动是一个非常重要的刺激因素,可对骨骼肌中的多种代谢和转录过程起调节作用。MAPK信号级联中有多种独立的信号途径参与了骨骼肌运动性适应的细胞调控过程,对骨骼肌中葡萄糖转运、胰岛素信号转导、钾离子转运、工作肌的可塑性等产生影响。     

连续力竭性运动后大鼠血乳酸的持续升高

连续力竭性运动后,大鼠血乳酸和肌乳酸浓度显著升高,而肌糖原显著降低。虽经48小时休息,血和肌乳酸浓度以及肌糖原均未能恢复至安静水平,肌细胞内线粒体明显水肿,显示乳酸未被有效氧化或合成糖原。这可能与细胞膜的转运障碍及线粒体氧化还原酶系的机能障碍有关。     

大强度间歇练习对红细胞膜蛋白功能的影响

目的:探讨运动过程中红细胞膜蛋白功能的变化规律。方法:选取武术系男子长拳专项学生为训练组(T组)8名,对照组(U组)为普通系男生8名。运动方式为功率自行车运动。肘静脉抽血5mL检验。结果:(1)T组与U组葡萄糖转运速率分别在运动后即刻,运动30min显著降低(P<0.05)。(2)U组阴离子转运功能在在运动后即刻30min阴离子转运功能显著下降(P<0.01)。(3)T、U组Na ,K -ATP酶活性在安静时,运动后即刻,运动后30min,运动后3h均有显著差异(P<0.05)。(4)相关分析表明三种红细胞膜蛋白的变化不相关。结论:大强度间歇练习对不同红细胞膜蛋白功能的影响是不同的,长期长拳练习可改善红细胞膜蛋白功能。目的:探讨运动过程中红细胞膜蛋白功能的变化规律。方法:选取武术系男子长拳专项学生为训练组(T组)8名,对照组(U组)为普通系男生8名。运动方式为功率自行车运动。肘静脉抽血5mL检验。结果:(1)T组与U组葡萄糖转运速率分别在运动后即刻,运动30min显著降低(P<0.05)。(2)U组阴离子转运功能在在运动后即刻30min阴离子转运功能显著下降(P<0.01)。(3)T、U组Na ,K -ATP酶活性在安静时,运动后即刻,运动后30min,运动后3h均有显著差异(P<0.05)。(4)相关分析表明三种红细胞膜蛋白的变化不相关。结论:大强度间歇练习对不同红细胞膜蛋白功能     

运动刺激骨骼肌葡萄糖转运的细胞信号转导机制

近来,骨骼肌葡萄糖转运的细胞信号转导机制研究十分活跃,但运动刺激骨骼肌葡萄糖转运的信号机制尚不明了。文章就运动刺激骨骼肌葡萄糖转运的胰岛素信号转导途径和非胰岛索信号转导途径两大方面的研究进展进行了综述（重点在非胰岛素途径）,并对二者的交叉作用作简要介绍,以促进对运动调节骨骼肌葡萄糖转运信号转导机制的深入研究。     

运动与p38MAPK

运动是一个非常重要的刺激因素,可对骨骼肌中的多种代谢和转录过程起到调节作用.MAPK信号级联中有多种独立的信号途径参与了骨骼肌运动性适应的细胞调控过程,对骨骼肌中葡萄糖转运、胰岛素信号转导、钾离子转运、工作肌的可塑性等产生影响     

运动裨益AD的机制：大脑糖代谢紊乱和特征性病理症状的协同改善

运动预防和延缓阿尔茨海默病（Alzheimer’s disease,AD）的作用机制并非仅与β-淀粉样蛋白（β-amyloid peptides, Aβ）、tau蛋白过度磷酸化等特征性病理症状改变有关,其可能是运动多靶点效应协同改善大脑葡萄糖代谢紊乱和AD特征性病理症状的结果。运动可发挥其多靶点效应,激活脑源性神经营养因子和腺苷酸活化蛋白激酶、Sirtuins等信号分子,上调胰岛素信号通路活性,抑制神经炎症诱发的胰岛素抵抗,增加葡萄糖转运载体表达,改善糖酵解、三羧酸循环和氧化磷酸化等葡萄糖氧化分解代谢途径障碍,从而协同改善大脑糖代谢紊乱和AD特征性病理症状,发挥抗AD的作用。     

运动、补糖或刺五加对大鼠糖原耗竭运动后肌细胞膜GLUT4转位的影响

目的:研究大鼠运动后骨骼肌细胞膜葡萄糖转运体4(Glucose transporter 4,GLUT4)转位及其时相性变化,并探索补糖和刺五加对其影响。方法:128只SD大鼠大鼠随机分为训练对照、训练补糖、训练补刺五加皂甙和训练补刺五加皂甙和糖4组,在糖原消耗性运动前和运动后不同时间点(0 h,4 h,12 h)采样,共16小组(n=8)。采用Western blotting方法分析骨骼肌细胞质膜和细胞膜的GLUT4的相对蛋白含量。结果:(1)糖原耗竭性运动后骨骼肌细胞内质膜GLUT4相对蛋白量明显降低(105.66±10.54 vs 98.05±11.89)。补充刺五加提高了骨骼肌的骨骼肌细胞内质膜GLUT4蛋白含量。(2)糖原耗竭性运动后即刻骨骼肌细胞膜的GLUT4相对蛋白量明显升高(100.47±10.40 vs 188.14±24.31)。补糖和刺五加可显著升高运动后骨骼肌细胞膜GLUT4相对蛋白含量。结论:运动后骨骼肌细胞膜GLUT4转位增加,补糖或补刺五加均可以促使运动后GLUT4转位增加。     

An acute bout of high-intensity intermittent swimming induces glycogen supercompensation in rat skeletal muscle

Abstract

High-intensity intermittent exercise substantially increases muscle glucose transport, which is thought to be the rate-limiting step for glycogen synthesis. In the present study, we compared muscle glycogen supercompensation after high-intensity intermittent exercise with that observed after low-intensity continuous exercise in rats. Four- to five-week-old male Sprague-Dawley rats performed either low-intensity swimming (240 min of swimming exercise with a weight equivalent to 1% of their body mass; LOW) or high-intensity swimming (twenty 30-s swimming bouts with 30 s rest between bouts with a weight equivalent to 16% of their body mass; HIGH) to deplete muscle glycogen. After the glycogen-depleting exercise, rats were given a rodent chow diet plus 5% glucose solution for 6 h or 24 h. Immediately after the two types of exercise, glycogen concentration in rat epitrochlearis muscle was similarly depleted. After the 6-h and 24-h recovery periods, muscle glycogen concentrations in both the HIGH and LOW groups were restored well above the normally fed state. Furthermore, muscle glycogen accumulation in the HIGH group for the 6-h and 24-h recovery periods was not significantly different from that observed in the LOW group. The high-intensity intermittent swimming exercise also induced muscle glycogen supercompensation in well-trained rats that had performed 7 days of endurance swimming training (6 h per day). Our results indicate that high-intensity intermittent exercise as well as low-intensity continuous exercise could induce glycogen supercompensation in rat skeletal muscle.     

运动干预代谢综合征机制研究进展

运动可通过提高胰岛素敏感性及葡萄糖的转运速度,促进骨骼肌利用葡萄糖而降低血糖;减轻体重,改善内脏脂肪堆积,降低血清低密度脂蛋白水平,促进胆固醇的逆向转运;改善血管内皮功能,降低血压,干预代谢综合征的发生与发展,减轻糖尿病、肥胖、高血压、血脂异常等代谢综合征的临床表现,起到预防和辅助药物治疗的作用。     

耐力训练时脂肪甘油三酯脂肪酶与工作肌糖代谢和线粒体密度——基于ATGL基因敲除小鼠的研究

目的：（1）观察ATGL基因敲除小鼠耐力训练时胰岛素抵抗、工作肌糖转运蛋白及线粒体密度的变化;（2）测定Akt、PKC、PPAR-α蛋白激活及含量,探究其与胰岛素抵抗、工作肌糖转运蛋白及线粒体密度的变化之间的关系。方法：ATGL^-/-、ATGL^+/-和C57BL/6J小鼠跑台耐力训练训练7天,测定小鼠体重、肌糖原、血糖、血胰岛素和胰岛素抵抗,蛋白印记法测定腓肠肌和比目鱼肌GLUT-4（内外膜）、p-Akt、Akt、p-PKC、PKC含量和PPAR-α水平。结果：（1）运动训练后,腓肠肌和比目鱼肌糖原含量、HOMA-IR指数存在基因类型、运动训练的差异（P<0.05）。运动训练引起血糖和血胰岛素在基因类型的差异（P<0.05）。（2）运动训练后,腓肠肌和比目鱼肌Akt、PKC、磷酸化水平、腓肠肌总Akt、PPAR-α蛋白表达存在基因类型、运动训练的差异（P<0.05）。比目鱼肌总Akt表达、腓肠肌和比目鱼肌总PKC、PPAR-α蛋白运动训练的差异不具有显著性意义（P>0.05）。结论：耐力训练时,ATGL通过上调Akt和PKC促进胰岛素敏感性和改善胰岛素抵抗;ATGL上调PPAR-α起到促进线粒体含量。     

Pre-exercise carbohydrate and fat ingestion: effects on metabolism and performance

A key goal of pre-exercise nutritional strategies is to maximize carbohydrate stores, thereby minimizing the ergolytic effects of carbohydrate depletion. Increased dietary carbohydrate intake in the days before competition increases muscle glycogen levels and enhances exercise performance in endurance events lasting 90 min or more. Ingestion of carbohydrate 3-4 h before exercise increases liver and muscle glycogen and enhances subsequent endurance exercise performance. The effects of carbohydrate ingestion on blood glucose and free fatty acid concentrations and carbohydrate oxidation during exercise persist for at least 6 h. Although an increase in plasma insulin following carbohydrate ingestion in the hour before exercise inhibits lipolysis and liver glucose output, and can lead to transient hypoglycaemia during subsequent exercise in susceptible individuals, there is no convincing evidence that this is always associated with impaired exercise performance. However, individual experience should inform individual practice. Interventions to increase fat availability before exercise have been shown to reduce carbohydrate utilization during exercise, but do not appear to have ergogenic benefits.     

Melatonin administration does not alter muscle glycogen concentration during recovery from exhaustive exercise in rats

Abstract

The purpose of this study was to investigate the effect of melatonin administration on muscle glycogen concentration during recovery after exhaustive swimming exercise in sedentary and trained rats. Male Wistar rats were assigned to one of four groups: sedentary control (C), sedentary melatonin-injected (M), exercise-trained (T), and trained and melatonin-injected (MT) groups. Exercise-trained groups were subjected to six weeks of swimming exercise. All rats completed an exhaustive swimming exercise. Two daily subcutaneous injections of melatonin at a dose of 3 mg·kg^?1 were given to the rats in the M and MT groups immediately after the exhaustive exercise. Plasma melatonin, glucose and lactate concentrations, and glycogen concentrations of the soleus and epitrochlearis muscle tissues were measured after exhaustive exercise. Plasma lactate concentration was significantly lower in the T and MT groups than in the C group. Plasma melatonin concentration was higher in the supplemented groups than in the C group. Plasma glucose concentration was significantly higher in the T and MT groups than in the C group. Both epitrochlearis and soleus muscle glycogen concentrations were higher in the trained groups than in the C group. In conclusion, although exercise training results in improvement in muscle glycogen, exogenous melatonin administration after exhaustive exercise did not restore the glycogen concentrations in fast- or slow-twitch muscle tissues.     

论骨骼肌内葡萄糖的转运

骨骼肌是葡萄糖最主要的利用者,同时也是碳水化合物的主要贮藏部位（占糖原总量的70％）。本文介绍了在运动过程中骨骼肌对葡萄糖利用及骨骼肌对葡萄糖利用的潜在机理。     

磷酯酰肌醇3激酶在骨骼肌中的调节以及运动对它的影响

在骨骼肌中磷酯酰肌醇3激酶(PI3K)以异二聚体形态存在.它以及它下游的靶目标和胰岛素受体底物(IRS1,2)一起在胰岛素信号转导通路中发挥重要作用,并参与了胰岛素刺激的葡萄糖转运和GLUT-4转移;不同强度运动以及运动时间对骨骼肌中PI3K有着不同的作用,这也和胰岛素的调节有关.     

The ingestion of combined carbohydrates does not alter metabolic responses or performance capacity during soccer-specific exercise in the heat compared to ingestion of a single carbohydrate

This study was designed to investigate the effect of ingesting a glucose plus fructose solution on the metabolic responses to soccer-specific exercise in the heat and the impact on subsequent exercise capacity. Eleven male soccer players performed a 90 min soccer-specific protocol on three occasions. Either 3 ml · kg(-1) body mass of a solution containing glucose (1 g · min(-1) glucose) (GLU), or glucose (0.66 g · min(-1)) plus fructose (0.33 g · min(-1)) (MIX) or placebo (PLA) was consumed every 15 minutes. Respiratory measures were undertaken at 15-min intervals, blood samples were drawn at rest, half-time and on completion of the protocol, and muscle glycogen concentration was assessed pre- and post-exercise. Following the soccer-specific protocol the Cunningham and Faulkner test was performed. No significant differences in post-exercise muscle glycogen concentration (PLA, 62.99 ± 8.39 mmol · kg wet weight(-1); GLU 68.62 ± 2.70; mmol · kg wet weight(-1) and MIX 76.63 ± 6.92 mmol · kg wet weight(-1)) or exercise capacity (PLA, 73.62 ± 8.61 s; GLU, 77.11 ± 7.17 s; MIX, 83.04 ± 9.65 s) were observed between treatments (P > 0.05). However, total carbohydrate oxidation was significantly increased during MIX compared with PLA (P < 0.05). These results suggest that when ingested in moderate amounts, the type of carbohydrate does not influence metabolism during soccer-specific intermittent exercise or affect performance capacity after exercise in the heat.