Corticosteroid-binding globulin during inflammation and burn injury: nutritional modulation and clinical implications

Corticosteroid-binding globulin (CBG) is the main carrier of glucocorticoids in mammals. Serum CBG shows little physiological variation with the exception of pregnancy. Experimental inflammation and burn injury decrease serum CBG in rats and while the mechanism of this effect is unknown, in vitro experiments suggest that interleukin-6 may be involved. In severely burned patients, we have found that CBG was markedly decreased within a few hours postinjury. This decrease lasted about 2 weeks and was accompanied by an increase in the free fraction of serum cortisol. In addition, serum CBG responded to dietary manipulation in these patients, with low fat feeding resulting in higher serum CBG concentrations and lower serum-free cortisol values. This feeding suggests that during severe stress, CBG may be important in regulating the amount of cortisol reaching target tissues such as the immune system and wounds.