EFEITO DA Lantana canescens Kunth SOBRE PARÂMETROS INFLAMATÓRIOS – in vivo

Abstract

ABSTRACT Medicinal plants are commonly used all over the world for the treatment or prevention of diseases. Some species of the genus Lantana, are used for therapeutic purposes. Lantana canescens Kunth is popularly used as an anti-inflammatory and for pain relief, however, has not been scientifically proven for these effects. Consequently, the objective of the present work was to evaluate the anti-inflammatory and anti-hyperalgic effects of this species. The hydroethylic extract of L. canescens (HELc) was analyzed by HPLC-DAD-EM and its composites were described. The acute toxicity of HELc (2000 mg/Kg) was assessed in female Swiss mice. Its anti-inflammatory and anti-hyperalgesic effects were evaluated in in vivo models, in male Swiss mice, for that, the tests of paw edema, mast cell degranulation, leukocyte influx, abdominal writhing test and formalin test were performed. The results were expressed as mean ± E.P.M., ANOVA and Bonferroni test (p < 0.05). The phytochemical characterization of HELc confirmed the presence of glycosylated iridoids (tevesideo, teviridosideo), verbascosides and flavonoids. The HELc did not present toxicity in the evaluated dose. In the tests, the mice were pretreated orally (v.o.) with water (control) or indomethacin (5 mg / kg, standard anti-inflammatory) or morphine (5 mg/kg, standard analgesic, formalin test). In the carrageenan-induced paw edema model, the peak of edema was at 240 minutes (0.098 ± 0.016 mL) and at that time the edema was inhibited by indomethacin in 74.0% and HELc (3, 30 and 300 mg/kg) in 44.0%, 54.0% e 72.0%, respectively. For the 48/80 compound-induced degranulation assay, indomethacin was reduced by 67.8%. HELc at the same previous doses reduced by 64.9%, 45.4% e 40.8%, respectively, no difference between doses. The leukocyte influx of the predominant cells in the inflammatory focus, polymorphonuclear cells (3085.0 ± 548.2 cell/mm3) into the peritoneal cavity of mice was reduced by indomethacin by 74.4% and the HELc reduced by an average of 54.2%, 56.3% e 62.3%, at doses of 3, 30 and 300 mg/kg, respectively. HELc did not alter the influx of mononuclear leukocytes. In the abdominal writhing test, acetic acid induced 87.0 ± 3.4 writhing episodes. Indomethacin inhibited the writhing episodes by 38.4% (53.6 ± 1.0 writhing episodes). HELc at doses 3, 30 and 300 mg/kg, inhibited the writhing episodes by 31%, 41%, and 35%, respectively. In the formalin test, in animals treated with water, the paw licking time was 64.6 ± 13.7 s in the first phase and 215.0 ± 4.8 s in the second phase. Morphine reduced this time by 99.0% in both phases. Indomethacin reduced the paw licking time by 43,3% on the second phase and HELc 3, 30 and 300 mg/Kg reduced by 40.7%, 36.3% and 33.4% respectively, in this same phase of the trial and showed no effect in phase I. It was concluded that HELc has anti-hyperalgesic and anti-inflammatory activity, validating its popular use. Keywords: Medicinal plants; pain; inflammation.