Modulation of the insulin-like growth factor system by chronic alcohol feeding
Modulation of the insulin-like growth factor system by chronic alcohol feeding
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DOI：
10.1097/00000374-199806000-00008
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发表时间：
1998-06-01
影响因子：
3.2
通讯作者：
McDonough, KH
中科院分区：
文献类型：
--
作者：
Lang, CH;Fan, J;McDonough, KH
胰岛素样生长因子(IGF)- 1是一种有效的合成代谢因子，在调节肌肉蛋白平衡中起重要作用。IGF系统的一种或多种成分的改变可能部分导致伴随慢性饮酒的肌肉萎缩。本研究的目的是表征大鼠慢性酒精消耗产生的生长激素- igf轴的变化。酒精喂养8周后，与成对喂养的对照动物相比，血浆中igf - 1浓度降低（31%），肝脏和骨骼肌中igf - 1浓度降低（40-50%）。此外，酒精消耗降低了肝脏和肌肉中IGF-I mRNA的丰度（接近50%）。十二指肠和肾脏中igf - 1的含量不受酒精喂养的影响。同时，与对照组相比，酒精喂养大鼠血浆、肝脏和肌肉中IGF结合蛋白(IGFBP)-1的相对浓度升高。相反，在这个时间点，酒精喂养大鼠的血浆中没有检测到IGFBP-2、-3或-4的浓度变化。先前的研究表明，糖皮质激素的升高或胰岛素或生长激素的降低可能导致其他分解代谢条件下igf -1的降低和/或IGFBP-1的增加。然而，在本研究中，这些激素的血浆浓度在酒精喂养的动物和对照组动物之间没有差异。这些数据表明，大鼠慢性酒精喂养降低了血液循环和骨骼肌中的IGF- 1并增加了IGFBP-1，这些变化似乎独立于IGF系统的经典激素调节因子的变化。观察到的IGF系统的改变与慢性饮酒引起的IGF- 1合成代谢作用的减少是一致的。
Insulin-like growth factor (IGF)-I is a potent anabolic agent that plays an important role in regulating muscle protein balance. Alterations in one or more of the various components of the IGF system may be in part responsible for the muscle wasting that accompanies chronic alcohol consumption. The purpose of the present study was to characterize changes in the growth hormone-IGF axis produced by chronic alcohol consumption in rats. After 8 weeks of alcohol feeding, the IGF-I concentration was decreased in plasma (31%) as well as in the liver and skeletal muscle (40-50%), compared with pair-fed control animals. In addition, alcohol consumption decreased IGF-I mRNA abundance in liver and muscle (similar to 50%). IGF-I content in duodenum and kidney, however, was not altered by alcohol feeding. Concomitantly, the relative concentration of IGF binding protein (IGFBP)-1 was increased in plasma, liver, and muscle of alcohol-fed rats, compared with control values. In contrast, no changes in the plasma concentrations of IGFBP-2, -3, or -4 were detected in alcohol-fed rats at this time point. Previous studies have indicated that elevations in glucocorticoids or decreases in insulin or growth hormone might be responsible for the decrease in IGF-I and/or the increase in IGFBP-1 in other catabolic conditions. However, there was no difference in the plasma concentrations of these hormones between alcohol-fed and control animals in this study. These data indicate that chronic alcohol feeding in rats decreases IGF-I and increases IGFBP-1 in the circulation and in skeletal muscle and that these changes appear to be independent of changes in classical hormonal regulators of the IGF system. The observed alterations in the IGF system are consistent with a reduction in the anabolic actions of IGF-I induced by chronic alcohol consumption.