Antinociceptive and anti-inflammatory activities of the ethanolic extract from Synadenium umbellatum pax. (euphorbiaceae)‎ leaves and its fractions

Abstract EN

Synadenium umbellatum Pax., popularly known in Brazil as “cola-nota,” “avelós,” “cancerola,” and “milagrosa”, is a plant species used in folk medicine for the treatment of inflammation, pain, and several diseases.

This study aimed to investigate the antinociceptive and anti-inflammatory activities of the ethanolic extract from Synadenium umbellatum Pax.

leaves (EES) and its hexane (HF), chloroform (CF), and methanol/water (MF) fractions using the acetic acid-induced abdominal writhing test, formalin-induced paw licking test, tail flick test, croton oil-induced ear edema test, and carrageenan-induced peritonitis test.

EES and MF reduced the number of acetic acid-induced abdominal writhes, while CF and HF did not.

EES effect on acetic acid-induced abdominal writhing was reversed with a pretreatment with naloxone.

EES reduced licking time in both phases of the formalin-induced paw licking test, but did not prolong the latency in the tail flick test.

These results show that EES presented antinociceptive activity, probably involving the opioid system, anti-inflammatory activity in the croton oil-induced ear edema test, and leukocyte migration into the intraperitoneal cavity.

MF also presented anti-inflammatory activity in the croton oil-induced ear edema test.

In conclusion, EES and MF have antinociceptive activity involving the opioid system and anti-inflammatory activity.