[Leptin decreases post-septic pulmonary and intestinal FABP levels and its mechanism]

To detect the effect of sepsis on fatty acid binding proteins (FABP) levels and corresponding enzymes in lung and intestine of mice, and to explore the role for FABP in acute inflammation.

A sepsis model of mice made with cecum deligation and perforation was established, and a radioimmunoassay for FABP and 96-well spectrophotometry assays for myeloperoxidase (MPO) and superoxide dismutase (SOD) which were related with clearance of free radicals,were used to detect their levels in lung and intestine homogenized fluids. Hematoxylin-eosin stain was used simultaneously to check the histopathologic chanes of both tissues.

Compared with sham group (108.11 +/- 94.03 and 67.22 +/- 19.47 ng/ml) 6 h and 12 h after sepsis, FABP levels in lung and intestine were significantly higher (204.98 +/- 70.72 and 154.29 +/- 60.14 ng/ml), respectively. Twelve hours after leptin (0.1 mg/kg i p) and indomethacin (2 mg/kg i p) injection, lung FABP level decreased and was lower than septic group (P < 0.05). Moreover, 12 h after sepsis intestinal FABP increased, but it decreased after leptin injection (419.80 +/- 80.06 vs 191.09 +/- 96.75 ng/ml), while indomethacin injection had no such effect. MPO and SOD activities in lung and intestine changed accordingly with time after sepsis, the effect of leptin and indomethacin injections on it had no significant correlation with FABP changes.

Leptin can protect vital organ functions such as lung and intestine after sepsis, as FABP levels, the cellular injury marker, were significantly lower than groups without injection. And this effect might have no correlation with the clearance factors of oxygenic free radicals such as MPO and SOD.