Insulin
negative regulation of protein secretion
Insulin decreases hepatic acute phase protein levels in severely burned children.
<h4>Background</h4>Severe burn induces the hepatic acute phase response. In this study, we wondered whether continuous insulin treatment decreases acute phase protein levels in the severely burned.<h4>Methods</h4>Eighteen children aged 2 to 17 years with burns >40% of total body surface area were randomized to receive either insulin (n=9) or no treatment (n=9) within 72 hours after injury until the wounds were 95% healed. Insulin was given at a continuous rate of > or =1.5 microU/kg/min to maintain euglycemia (serum glucose 100-140 microg/dL). Plasma was examined at days 7, 14, 21, and 28 for acute phase protein levels including C-reactive protein, C3 complement, alpha1-acid glycoprotein, haptoglobin, alpha2-macroglobulin, prealbumin, transferrin, and retinol-binding protein. Statistical analysis was by ANOVA and t test.<h4>Results</h4>With insulin treatment, alpha1-acid glycoprotein, C3 complement, alpha2-macroglobulin, and haptoglobin levels decreased (P<.05) after a severe burn compared with control, especially at days 21 and 28. Additionally, the hepatic constitutive proteins (prealbumin, transferrin, and retinol-binding protein) were lower in the insulin-treatment group than those of the control group at day 21 (P<.05).<h4>Conclusions</h4>Continuous insulin treatment decreases acute phase protein levels after a severe burn. The results suggest insulin downregulation of the hepatic acute phase response to injury.