Recombinant Human Growth Hormone Increases Thyroid Hormone-Binding Sites in Recovering Severely Burned Children

Abstract

Thyroxine (T4), Tri-iodothyronine (T3), and total serum protein levels are reduced in severely burned children. T4 and T3 are carried on serum transport proteins via thyroid hormone-binding sites (THBS). Treatment of bums with recombinant human growth hormone (rhGH) increases albumin (Alb) and prealbumin (PreAlb), which bind nearly 30% of circulating T4 and T3. This study investigated the effect of rhGH on THBS sites in burned children. Records of 11 acutely burned children with a total body surface area burned >40% who were randomized to either a daily subcutaneous injection of rhGH at 0.05 mg/kg/day or placebo for 6 months after discharge from hospital were reviewed. Thyroxine uptake percentage (TU%), Total T4 levels (TT4), free thyroxine index, Alb and PreAlb, and height and weight measurements taken at discharge and 6 months later were compared in both groups. In the six children who received rhGH, mean TU% had decreased from 41 +/- 1 to 33 +/- 1% by 6 months postdischarge, (P < 0.001), mean TT4 increased from 5.8 +/- 0.3 to 8.1 +/- 0.8 microg/dL, (P < 0.02), mean Alb increased from 2.0 +/- (0.6) to 3.5 +/- (0.1) g/dL (P < 0.0001), and mean PreAlb increased from 8.7 +/- 0.7 to 16.5 +/- 2.1 mg/dL, (P < 0.006). There were no significant changes in the five children in the placebo (control group), and height and weight did not significantly change in either group. rhGH significantly increases THBS in severely burned children, possibly through increases in serum Alb and PreAlb. The increases in circulating thyroxine observed in this group may be involved in the attenuation of growth arrest.

The Evaluation of the Adrenal and Thyroid Axes and Glucose Metabolism after Burn Injury in Children

“…These few studies report that thyroid hormones are low following burn injury, as in adults 32,33 . Thyroid hormones are reported to fall, especially in major burns, possibly due to the body's metabolic adaptation 34 .…”

A proteomic approach identified growth hormone-dependent nutrition markers in children with idiopathic short stature

“…The intensity of the transthyretin peak increased in the low-responder group and decreased in the high-responder group during GH treatment. Interestingly, GH administration has also been shown to increase serum levels of transthyretin in severely burned children and in adults after hepatectomy [ 15 , 16 ], suggesting a common mechanism between serious illness and low GH responsiveness. Our results are in line with a report showing that serum levels of transthyretin in rats were markedly decreased by hypophysectomy and further decreased after GH replacement [ 17 ].…”

Anabolic and anticatabolic agents used in burn care: What is known and what is yet to be learned

“…Conflicting results have been published about the effect of rhGH on the healing time of donor sites. (79)(80)(81)(82)(83)(84)(85)(86)(87)(88)(89)(90)(91)(92) Kim and colleagues studied adults with full thickness burns greater than 20% TBSA and showed that treatment with rhGH for 3 months during rehabilitation phase increases fitness levels, muscle power and metabolic processes. (93) Growth hormone supplementation and mortality have been the focus of debate in the literature.…”