Role of insulin-like growth factors and growth hormone in reversing catabolic states.

The insulin-like growth factors (IGFs) mediate the anabolic effects of growth hormone or protein synthesis in muscle and skeletal tissues. Administering growth hormone to normal volunteers who have been made catabolic by caloric restriction improves the nitrogen balance. The studies described illustrate that administration of somatomedin-C (IGF-I) to catabolic normal volunteers also results in improved nitrogen balance and, unlike growth hormone, does not induce insulin resistance. Growth hormone was anabolic in patients with severe chronic obstructive lung disease and resulted in improved chest wall muscle strength. Both IGF-I and growth hormone have the potential to improve muscle mass and function in patients who are catabolic due to the severity of their underlying disease state.