Impact of exogenous insulinlike growth factor 1 on hepatic energy metabolism in burn injury

Y. L. Dong, K. F. Huang, Z. F. Xia, D. H. Chung, T. Z. Yan, D. N. Herndon and J. P. Waymack
Shriners Burn Institute, Galveston Tex.

BACKGROUND: Insulinlike growth factor 1 (IGF-1) has previously been demonstrated to improve the nutritional status of burned animals. The method by which it achieves this result has not yet been fully elucidated, but may be the result of alterations in hepatic metabolism. OBJECTIVE: To determine if IGF-1 is able to correct the burn-induced impairments in hepatic metabolic function. DESIGN: Seventy-two Sprague-Dawley rats were subjected to a sham burn (n = 24), or a 50% total body surface area scald burn (n = 48). Half the scald burn group received 3 micrograms/kg per day of IGF-1. The remainder received a placebo. The rats were sequentially assayed for multiple components of hepatic function. RESULTS: Insulinlike growth factor 1 corrected the burn-induced decrease in hepatic adenosine triphosphate concentration and prevented the burn-induced increase in hepatic ketone body levels. Insulinlike growth factor 1 was also able to prevent the burn-induced decrease in the hepatic acetoacetate-beta-hydroxybutyrate ratio. Since this ratio is directly proportional to mitochondrial redox potential this indicates that IGF-1 is also able to prevent the burn-induced impairment in hepatic redox potential. CONCLUSIONS: These data indicate that part of the previously demonstrated beneficial effect of IGF-1 in burn injury may be due to its ability to improve multiple components of hepatic metabolism.