Analgesic effect of methanolic extract obtained from Schinus terebinthifolius leaves

Abstract

Previous studies from our group showed the analgesic effects of essential oil and extracts of Schinus terebinthifolius. The aims of this research were to evaluate the anti-nociceptive, anti-arthritic properties of methanolic extract obtained from S. terebinthifolius (MEST) leaves in animal models of experimental pain and arthritis. The MEST (30 and 100 mg/kg) reduced both phases of formalin induced licking behavior in Swiss mice. The MEST (100 mg/kg) reduced mechanical hyperalgesia induced by carrageenan in swiss mice. The MEST (100 mg/kg) oral administration reduced significantly the mechanical hyperalgesia (day 2, 5, 10, and 20), knee oedema (day 2), cold (day 15) and heat sensitivity (day 20), but not depressive-like behavior (Forced Swim Test), after Complete Freund's Adjuvant (CFA) in C57B16 mice. The MEST prevented the anti-nociceptive effects in formalin nociception and did not interfere with locomotor activity in Swiss mice (open field test). The MEST was effective for the inhibition of pain and arthritic parameters without altering locomotor activity or depressive-like behavior. The present results may open new possibilities for the development of new analgesic agents from S. terebinthifolius.