Mechanism involved in the anti-inflammatory effect of Spiranthera odoratissima (Manacá)

Acetic acid-induced writhing, hot-plate, carrageenan-induced pleurisy, formalin-induced pain, croton oil-induced ear edema, vascular permeability tests and phospholipase A2 activity assay were used to study the analgesic and/or anti-inflammatory activity of the hydromethanolic fraction of ethanolic extract from Spiranthera odoratissima A. St.-Hil., Rutaceae, leaves (HMF) and its subfraction (sub-Fr10-28). HMF and sub-Fr10-28 reduced the leukocyte migration on the carrageenan-induced pleurisy test; sub-Fr10-28 reduced the pain reaction time in the second phase of formalin-induced pain, as well as the ear edema and vascular permeability. Both HMF and sub-Fr10-28 inhibited the phospholipase A2 activity. These results suggest that the analgesic effect of this plant could be, in part, due to an anti-inflammatory action produced by the inhibition of phospholipase A2 activity.

Anti-inflammatory and opioid-like activities in methanol extract of Mikania lindleyana, sucuriju

Mikania lindleyana DC., Asteraceae (sucuriju), grows in the Amazon region, where is frequently used to treat pain, inflammatory diseases and scarring. This study was carried out to investigate phytochemical profile accompanied by in vivo antinociceptive and anti-inflammatory screening of n-hexane (HE), dichloromethane (DME) and methanol (ME) extracts obtained from the aerial parts of the plant. The oral administration of ME (0.1, 0.3, 1 g/kg) caused a dose-related reduction (16.2, 42.1 e 70.2 percent) of acetic acid-induced abdominal writhing while HE and DME (1 g/kg, p.o.) were ineffective. In the hot plate test, ME (300 mg/kg, p.o.) increased the latency of heat stimulus between 30 and 120 min and inhibited the first (45 percent) and second (60 percent) phases of nociception in the formalin test. The antinociception induced by ME or positive control fentanyl (150 µg/kg, s.c.) in hot plate and formalin tests was prevented by naloxone (3 mg/kg, s.c.). When submitted to the carrageenan-induced peritonitis test, ME (0.5, 1.0, 2.0 g/kg, p.o.) impaired leukocyte migration into the peritoneal cavity by 46.8, 59.4 and 64.8 percent respectively, while positive control dexamethasone (2 mg/kg, s.c.), inhibited leukocyte migration by 71.1 percent. These results indicate that the antinociception obtained after oral administration of methanol extract of M. lindleyana involves anti-inflammatory mechanisms accompanied with opioid-like activity which could explain the use of the specie for pain and inflammatory diseases.