Hickey M S, Carey J O, Azevedo J L, Houmard J A, Pories W J, Israel R G, Dohm G L
Human Performance Laboratory, School of Health and Human Performance, East Carolina University, Greenville, North Carolina 27858.
Am J Physiol. 1995 Mar;268(3 Pt 1):E453-7. doi: 10.1152/ajpendo.1995.268.3.E453.
The purpose of this study was to determine if a relationship exists among skeletal muscle fiber composition, adiposity, and in vitro muscle glucose transport rate in humans. Rectus abdominus muscle was obtained during elective abdominal surgery from nonobese control (n = 12), obese (n = 12), and obese non-insulin-dependent diabetes mellitus (NIDDM) patients (n = 10). The obese NIDDM group had a significantly lower percentage of type I muscle fibers (32.2 +/- 1.9%) than the obese group (40.4 +/- 2.7%), and both obese groups were significantly lower than the control group (50.0 +/- 2.6%). Insulin-stimulated glucose transport, determined on 28 subjects, was significantly lower in both the obese (3.83 +/- 0.48 nmol.min-1.mg-1) and NIDDM (3.93 +/- 1.0 nmol.min-1.mg-1) groups vs. the control group (7.35 +/- 1.50 nmol.min-1.mg-1). Body mass index (BMI) was inversely correlated to percent type I fibers (r = -0.50, P < 0.01) and to the insulin-stimulated glucose transport rate (r = -0.53, P < 0.01). The percentage of type I muscle fibers was related to the insulin-stimulated glucose transport rate (r = 0.57, P < 0.01), although this relationship was not significant after adjusting for BMI. Although these data do not support an independent relationship between fiber type and insulin action in obesity, a reduced skeletal muscle type I fiber population may be one component of a multifactorial process involved in the development of insulin resistance.
本研究的目的是确定人类骨骼肌纤维组成、肥胖程度与体外肌肉葡萄糖转运速率之间是否存在关联。在择期腹部手术期间，从非肥胖对照组（n = 12）、肥胖组（n = 12）和肥胖非胰岛素依赖型糖尿病（NIDDM）患者（n = 10）获取腹直肌。肥胖NIDDM组的I型肌纤维百分比（32.2 +/- 1.9%）显著低于肥胖组（40.4 +/- 2.7%），且两个肥胖组均显著低于对照组（50.0 +/- 2.6%）。对28名受试者测定的胰岛素刺激的葡萄糖转运，肥胖组（3.83 +/- 0.48 nmol·min-1·mg-1）和NIDDM组（3.93 +/- 1.0 nmol·min-1·mg-1）均显著低于对照组（7.35 +/- 1.50 nmol·min-1·mg-1）。体重指数（BMI）与I型纤维百分比呈负相关（r = -0.50，P < 0.01），与胰岛素刺激的葡萄糖转运速率呈负相关（r = -0.53，P < 0.01）。I型肌纤维百分比与胰岛素刺激的葡萄糖转运速率相关（r = 0.57，P < 0.01），尽管在调整BMI后这种关系不显著。虽然这些数据不支持肥胖中纤维类型与胰岛素作用之间存在独立关系，但骨骼肌I型纤维数量减少可能是胰岛素抵抗发生的多因素过程的一个组成部分。
