THE 2α-3β-6β-23-TETRAHYDRO-OLEAN-12-EN-28-OIC ACID FROM THE LEAVES OF CHRYSOBALANUS ICACO L. ATTENUATES THE INFLAMMATORY HYPERNOCICEPTION IN MICE

Abstract

Objective: The species Chrysobalanus icaco L., popularly known as abajurú, abajeru, has frequently been associated with antiangiogenic, anti-inflammatory and antirheumatic effects. The 2α-3β-6β-23-tetrahydro-olean-12-en-28-oic acid (THOA) was isolated from the methanolic extract of Chrysobalanus icaco leaves. Thus, the aim of the study was to evaluate the antinociceptive and anti-inflammatory activities of THOA.Methods: Acetic acid-induced abdominal writhing, formalin, von frey and open field tests were performed in mice. The number of writhes, licking time, mechanical threshold and walked squares by animals were the evaluation parameters applied, respectively. In addition, quantification of IL-1β and TNF-α were also performed. The THOA was administered orally at doses of 1–10 mg/kg in male mice. In addition, water, vehicle, morphine (5.01 mg/kg), acetylsalicylic acid (100 mg/kg), and dexamethasone (2.25 mg/kg) were administered.Results: The THOA showed effect with 5 and 10 mg/kg in the acute pain induced by acetic acid (49% and 62% contortion inhibition), carrageenan (150% and 188% increase in mechanical threshold) and formalin (36% and 60% licking inhibition), respectively. These results indicate an inhibition of hyper nociception, while the reduction in the production of cytokines (TNF-α inhibition–64% and 88%; IL-1β inhibition–48% and 55%, respectively) confirmed the inflammatory inhibition by carrageenan. The THOA did not induce motor impairment. The THOA was not toxic after oral administration (LD50>50 mg/kg).Conclusion: These data provide initial evidence that THOA decreases the inflammatory hyper nociception probably by inhibition of IL-1β and TNF-α production, proving to be effective in reducing pain and inflammation.