[Differences in the dynamics of leptin and cortisol during the non-infectious stress reaction]

Leptin is a hormone and acute phase reactant with multiple effects during both rest and inflammatory period. Effects of leptin in acute phase response cover a modulation of hypothalamo-pituitoadrenal (HPA) axis, too. In our study we evaluate the dynamics of leptin and glucocorticoid acute changes in model situations of infectious and non-infectious inflammatory reaction.

This study was realized on a group of patients 1--after operation of carcinoma coli (16 persons), 2--after laparoscopic non-adjustable gastric banding (13 persons), and patients 3--with development of postoperative intraabdominal sepsis (22 persons). Plasma levels of leptin, ACTH, cortisol, TNF-alpha, IL-6, C reactive protein (CRP), and alpha1-antitrypsin (AAT) were measured from -7 to +3 day related to surgery or 2nd day after a day when signs of sepsis were occurred.

All tested parameters responded to surgical trauma with elevation 12 h after operation except leptin that elevated +24 h after surgery. Maximal levels of measured parameters were found 12 h after surgery (for cortisol), 24 h after surgery (for leptin, TNF-alpha, IL-6), or 36 h after operation (for CRP and AAT). Maximal levels of cortisol after a resection of coli or maximal levels of leptin after laparoscopic gastric banding fall to septic range. Other parameters in uncomplicated postoperative period significantly differed from septic levels on p < 0.01. There wasn't found statistically significant correlation between leptin and cortisol or between leptin and ACTH in all groups.

The elevation of leptin in postoperative period and during sepsis reflects a different regulation of this protein in rest period and during systemic inflammatory response. The inhibitory effect of leptin to HPA axis during stress response was documented in vitro, however, its physiological importance is not clear, yet. Our study didn't prove a statistically significant relation between plasma cortisol and leptin. The different dynamics of leptin and cortisol after surgical trauma shows that both factors have own specific regulation.