Antinociceptive and anti-inflammatory activities of lectin from the marine green alga Caulerpa cupressoides.

The search for new compounds for controlling pain and inflammation, with minimal side effects has focused on marine algae. The aim of this work was to investigate the effect of the purified lectin from the green marine alga Caulerpa cupressoides (CcL) in classical models of nociception and inflammation. Male Swiss mice received i.v. CcL 30 min prior to receiving 0.8% acetic acid (10 ml/kg; i.p); 1% formalin (20 microl; s.c.) or were subjected to thermal stimuli. We observed that CcL (3, 9 or 27 mg/kg) significantly reduced the number of writhes induced by acetic acid by 37.2%; 53.5% and 86.0%, respectively. CcL (27 mg/kg) also reduced the second phase of the formalin test. However, CcL (27 mg/kg) did not present significant antinociceptive effects in the hot plate test, when compared to morphine, suggesting that its antinociceptive action occurs predominantly through a peripheral mechanism. The antinociceptive effects were abolished when CcL was pre-incubated with mucin (20mg/kg; i.v.). When CcL (9 mg/kg) was administered i.v. in Wistar rats 30 min before carrageenan administration, neutrophil counts were reduced by 65.9%. CcL also inhibited paw edema in all time intervals, especially at the third hour. Finally, CcL (9 mg/kg) administered i.v. in mice did not cause hepatic or renal alterations and did not affect body mass or macroscopy of the organs examined. In conclusion, CcL appears to have important antinociceptive and anti-inflammatory activities and could represent an important agent for future studies.