Growth hormone resistance

Hull K L, Harvey S (1999). Growth hormone resistance Clinical states and animal models. J. Endocrinol. 163(2) 165-172. 

The production of both anabolic sex hormones and growth hormone decreases in aging and the result is muscle loss. Also the loss of neural motor cells gives rise to atrophy of the muscles. In the aging process an increased inflammatory activity can be seen and it causes degeneration of muscle tissue through insuline resistance and activation of protein breakdown enzymes. The increased inflammatory activity is due to both normal aging as well as the presence of multiple chronic diseases (Dutta 1997. 

Mantovani, G., Maghnie, M., Weber, G., et al. (2003) Growth hormone-releasing hormone resistance in pseudohypoparathyroidism type la new evidence for imprinting of the Gs alpha gene. J. Clin. Endocrinol. Metab. 88, 4070 074. 

Modifications designed to enhance the enzyme resistance and prolong the activity of SS derivatives have been quite successful. The use of D-amino acids instead of the normal L-enantiomers (e.g., in Trp ), or replacement of the disulfide link by a nonreducible ethylene bridge, leads to an increased duration of activity, approaching 3 hours. Several analogs show a greatly increased effect, like the [D-Ala, D-Trp ]somatostatin, which has 20 times the activity of SS on growth hormone release. The NH-terminal outside the cyclic dodecapeptide is not essential for activity. Selectivity of action results from... 

Various hormonal agents (eg, glucocorticoids) lower the affinity of insulin receptors for insulin growth hormone in excess increases this affinity slightly. Aberrant serine and threonine phosphorylation of the insulin receptor subunits or IRS molecules may result in insulin resistance and functional receptor down-regulation. 

Hyperinsulinemia is common in recipients of somatropin, but the long-term effects are controversial. This issue is becoming increasingly important as more adult patients are treated and the duration of therapy is extended. Growth hormone deficiency is itself associated with insulin resistance (36). Plasma concentrations of glucose and hemoglobin Aic increase, especially in the first 6-12... 

Johansson JO, Fowelin J, Landin K, Lager I, Bengtsson BA. Growth hormone-deficient adults are insulin-resistant. Metabolism 1995 44(9) 1126-9. 

Jeffcoate W. Growth hormone therapy and its relationship to insulin resistance, glucose intolerance and diabetes mel-litus a review of recent evidence. Drug Saf 2002 25(3) 199-212. 

Saenger P. Assessing insulin resistance application of a fasting glucose to insulin ratio in growth hormone-treated children. Horm Res 2002 57(l-2) 37-42. 64. 

Growth hormone is one of the glucose counterregulatory hormones. It is released in response to hypoglycemia and has intrinsic hyperglycemic actions and causes insulin resistance. 

Duquesnoy, P., Sobrier, M. L., Duriez, B., Dastot, F., Buchanan, C. R., Savage, M. O., Preece, M. A., Craescu, C. T., Blouquit, Y., and Goossens, M. et al. (1994). A single amino acid substitution in the exoplasmic domain of the human growth hormone (GH) receptor confers familial GH resistance (Laron syndrome) with positive GH-binding activity by abolishing receptor homodimerization. EMBO J. 13(6), 1386-1395. 

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