Differential Effects Of HGH And IGF-I On Body Proportions

Me: This post shows that the effects of HGH and IGF-1 are actually different for different areas in the body. I showed in a recent post that the inject of IGF-2 in a localized region of the long bone (distal femoral epiphysis) lead to the long bone (femur) to lengthen. We know that from growth plate analysis that the growth plates have receptors for both GH and IGF-2, but from my personal research, the IGF-2 might have a more regional localized effect leading to increased limb length then torso/body length. However this study was done for IGF-1, bot IGF-2. 
Analysis & Interpretation of study: It is important to realized that the upper/lower body segment interpretation means the lower body is the leg/limbs while the upper body is the torso. So a higher U/L value means there was more lengthening effect on the torso than the limbs. A lower U/L value means there was more lengthening on the limbs then the torso. It seems that with kids who have some form of growth hormone deficiency (isolated and multiple pituitary hormone deficiency) the limbs were the primary area of lengthening from using the hGH injections. However with kids who suffered from Laron’s Syndrome, intrauterine growth retardation, or idiopathic short stature the treatment with either IGF-1 or hGH did not change the U/L but did result in increase height so it seems that with these types of disorders, the distributed effect by the GH or IGF-1 was even throughout the body. 
From PubMed article link HERE…
Anthropol Anz. 2012 Jul;69(3):255-9.

Differential effects of hGH and IGF-I on body proportions.

Laron Z, Silbergeld A, Kauli R.

Source

Endocrinology and Diabetes Research Unit, Schneider Children’s Hospital, WHO Collaborating Center for Diabetes in Youth Petah Tikva and Sackler School of Medicine, Tel Aviv, Israel. laronz@clalit.org.il

Abstract

The differential growth effects of hGH and IGF-I on the upper/lower (U/L) body segment in relation to height (Ht) were analyzed in 15 patients with isolated Growth hormone deficiency (IGHD,:7M, 8F) mean age 5.0 +/- 3.2 (SD) years treated with hGH; 21 patients with multiple pituitary hormone deficiency including growth hormone (MPHD: 14M, 7F) aged 10.0 +/- 3.8, treated with hGH; 9 patients with Laron Syndrome (LS) (4M,5F) aged 6.9 +/- 5.6 years treated with IGF-I; 9 boys with intrauterine growth retardation (IUGR) aged 6.3 +/- 1.25 years treated by hGH; and 22 boys with idiopathic short stature (ISS) aged 8.0 +/- 1.55 years treated by hGH. The dose of hGH was 33 microg/kg/day, that of IGF-I 180-200 microg/kg/day. RESULTS: the U/L body segment ratio in IGHD patients decreased from 2.3 +/- 0.7 to 1.1 +/- 0.7 (p <0.001), and the Ht SDS increased from -4.9 +/- 1.3 to 2.3 +/- 1 (p < 0.001) following treatment. In MPHD patients the U/L body segment decreased from 1.1 +/- 1.1 to -0.6 +/- 1.0 (p < 0.001), and the Ht SDS increased from -3.3 +/- 1.4 to -2.5 +/- 1.0 (p < 0.009). In the LS group the U/L body segment ratio did not change with IGF-I treatment but Ht improved from -6.1 +/- 1.3 to -4.6 +/- 1.2 (p < 0.001), The differential growth response of the children with IUGR and with ISS resembled that of the children with LS. CONCLUSIONS: hGH and IGF-I act differentially on the spine and limbs.

PMID: 22928349   [PubMed – indexed for MEDLINE]