Leptin as an acute phase reactant after non-adjustable laparoscopic gastric banding

Leptin is a hormone that regulates food intake; its concentrations are elevated in the majority of obese individuals. During inflammation, plasma leptin is usually increased and may contribute to the anorexia and cachexia of infection. The purpose of this study was to characterize the dynamics of circulating leptin in the early postoperative period in relation to the acute phase response in extremely obese patients undergoing laparoscopic non-adjustable gastric banding (LNAGB). We compared plasma leptin changes with 4 proinflammatory cytokines and BMI.

The prospective study was performed on 18 patients with 3rd degree obesity. Plasma concentration of leptin, tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1, soluble IL-2 receptor (sIL-2R), and IL-6 were estimated before operation and 24, 48, and 72 h after NALGB.

We demonstrate statistically significant elevation of plasma leptin concentration (32.2 +/- 10.2 micrograms/l) 24 h after operation compared with preoperative status (18.4 +/- 5.2 micrograms/l, p < 0.05). There was diminished correlation of plasma leptin and BMI in this period. Leptin levels +48 and +72 h after banding quickly returned to preoperative levels. The regression coefficient was the highest for leptin and TNF-alpha 24 h after surgery (r = 0.40, p < 0.05), and for leptin and IL-6 24 h after surgery (r = 0.29, p < 0.05). There was no significant correlation between leptin and IL-1 and between leptin and sIL-2R respectively.

During the non-infectious stress response (as with abdominal surgery), leptin shows itself as an acute phase reactant. Proinflammatory cytokines can be the main regulatory factors of leptin in this period. Significant correlation between leptin and TNF-alpha (similarly demonstrated by other authors in models of bacterial inflammation) indicates that TNF-alpha can be a crucial regulator of leptin generation in the early postoperative period.