Antinociceptive effect and gastroprotective mechanisms of 3,5-diprenyl-4-hydroxyacetophenone from Ageratina pichinchensis

The present study aimed to evaluate the antinociceptive activity (in inflammatory and neuropathic pain models) and gastroprotective effect of the 3,5-diprenyl-4-hydroxyacetophenone (HYDP), isolated from Ageratina pichinchensis . The gastroprotective activity of this plant was previously reported by our workgroup, finding encesanescin to be one active compound. The present results show that HYDP reduced nociception in a dose-dependent manner in carrageenan and L5/L6 spinal nerve ligation, with efficacies of 72.6 and 57.1%, respectively, at doses of 100 and 562 mg/kg. HYDP also showed gastroprotective activity in the model of ethanol-induced gastric lesion, with a 75.59% maximum inhibition of ulcers at a dose of 100 mg/kg. This gastroprotective effect was attenuated by N G -nitro- l -arginine methyl ester, indomethacin and N-ethylmaleimide, indicating that NO, prostaglandins and sulfhydryl groups are involved in the mechanisms of action. This is the first evidence, to our knowledge, of the antinociceptive and gastroprotective activities of HYDP.