Febbraio Mark A, Hiscock Natalie, Sacchetti Massimo, Fischer Christian P, Pedersen Bente K
Skeletal Muscle Research Laboratory, Center for Nutrition, Metabolism and Endocrinology, RMIT University, P.O. Box 71, Bundoora 3083, Victoria, Australia.
Diabetes. 2004 Jul;53(7):1643-8. doi: 10.2337/diabetes.53.7.1643.
The mechanisms that mediate the tightly controlled production and clearance of glucose during muscular work are unclear, and it has been suggested that an unidentified "work factor" exists that influences the contraction-induced increase in endogenous glucose production (EGP). The cytokine interleukin (IL)-6 is released from skeletal muscle during contraction. Here we show that IL-6 contributes to the contraction-induced increase in EGP. Six men performed 2 h of bicycle exercise on three separate occasions, at a relatively high intensity (HI) or at a low intensity with (LO + IL-6) or without (LO) an infusion of recombinant human IL-6 that matched the circulating concentration of IL-6 seen in HI exercise. The stable isotope 6,6 (2)H(2) glucose was infused to calculate EGP (rate of glucose appearance [R(a)]), whole-body glucose disposal (rate of glucose disappearance [R(d)]), and metabolic clearance rate (MCR) of glucose. Glucose R(a), R(d), and MCR were higher (P < 0.05) at HI than at LO. Throughout exercise at LO + IL-6, glucose R(a) and R(d) were higher (P < 0.05) than LO, even though the exercise intensity was identical. In addition, MCR was higher (P < 0.05) at LO + IL-6 than at LO at 90 min. Insulin, glucagon, epinephrine, norepinephrine, cortisol, and growth hormone were identical when comparing LO + IL-6 with LO. These data suggest that IL-6 influences glucose homeostasis during exercise. Our results provide potential new insights into factors that mediate glucose production and disposal and implicates IL-6 in the so-called "work factor."
在肌肉运动期间介导葡萄糖产生和清除受到严格控制的机制尚不清楚，有人提出存在一种未知的“工作因子”，它会影响收缩诱导的内源性葡萄糖生成（EGP）增加。细胞因子白细胞介素（IL）-6在收缩过程中从骨骼肌释放。在这里，我们表明IL-6促成了收缩诱导的EGP增加。六名男性在三个不同场合进行了2小时的自行车运动，分别是相对高强度（HI）运动，或低强度运动且伴有（LO + IL-6）或不伴有（LO）重组人IL-6输注，输注的IL-6浓度与HI运动时的循环IL-6浓度相当。输注稳定同位素6,6 - 2H2葡萄糖以计算EGP（葡萄糖出现率[R(a)]）、全身葡萄糖处置（葡萄糖消失率[R(d)]）和葡萄糖的代谢清除率（MCR）。HI运动时的葡萄糖R(a)、R(d)和MCR高于低强度运动（P < 0.05）。在LO + IL-6的整个运动过程中，尽管运动强度相同，但葡萄糖R(a)和R(d)高于LO（P < 0.05）。此外，在90分钟时，LO + IL-6的MCR高于LO（P < 0.05）。比较LO + IL-6与LO时，胰岛素、胰高血糖素、肾上腺素、去甲肾上腺素、皮质醇和生长激素水平相同。这些数据表明IL-6在运动期间影响葡萄糖稳态。我们的结果为介导葡萄糖产生和处置的因素提供了潜在的新见解，并将IL-6与所谓的“工作因子”联系起来。
