Anti-hyperalgesic activity of corilagin, a tannin isolated from Phyllanthus niruri L. (Euphorbiaceae)

Ethnopharmacological relevance: Corilagin (beta-1-O-galloy1-3,6-(R)-hexahydroxydiphenoyl-D-glucose) is a tannin isolated from Phyllanthus niruri (Euphorbiaceae). This plant is well known for their therapeutic purposes to treat several diseases associated with dolorous process and are used in several ethno-medicines in tropical and subtropical countries. Aim of the study: This study was designed to evaluate the anti-hyperalgesic activity of corilagin using chemically and thermally based nociception models in mice. Materials and methods: Corilagin was isolated from Phyllanthus niruri (Euphorbiaceae) by extraction and chromatographic procedures and the anti-hyperalgesic activity was evaluated by using writhing, formalin, capsaicin, glutamate and hot plate tests in mice. Results: Corilagin presented activity in acetic acid model with the ID50 calculated value of 6.46 (3.09-13.51) being about 20.6 fold more potent than acetylsalicylic acid. It also exhibited activity against the first phase of formalin test with ID50 value of 18.38 (15.15-22.59) mu mol/kg. In the capsaicin and glutamate models, corilagin demonstrated significant activity at the 3 mg/kg. Conclusion: The experimental data demonstrated that corilagin exhibits anti-hyperalgesic activity that may be due to interaction with the glutamatergic system. (C) 2013 Elsevier Ireland Ltd. All rights reserved.