Anti-inflammatory activity of aqueous leaf extract of Phyllanthus muellerianus (Kuntze) Exell. and its major constituent, geraniin

Ethnopharmacological relevance: Phyllanthus muellerianus (Kuntze) Exell. which belongs to the Family Euphorbiaceae is a shrub widely distributed in West Africa. It is used traditionally to manage wounds and wound infections, menstrual disorders, fevers, pain and inflammation. Hence to confirm its ethnobotanical uses in managing inflammation, we investigated the anti-inflammatory properties of aqueous leaf extract of P. muellerianus (PLE) and its major isolate, geraniin in experimentally-induced inflammation in rats. Materials and methods: Carrageenan induced oedema and adjuvant induced arthritis models in rats were used in this study. Results: In the carrageenan-induced acute inflammation, both 300 mg/kg PLE-treated and 10 mg/1<g geraniin-treated groups significantly reduced the mean maximal swelling attained at 4 h to 46.75 +/- 4.97% (p < 0.01) and 61.65 +/- 6.70% (p < 0.05), respectively, from the inflamed control response of 122.60 +/- 16.39%. In the adjuvant-induced chronic inflammation, both PLE-treated (100 and 300 mg/kg) groups and geraniin-treated (10 and 30 mg/kg) groups significantly (p < 0.001) reduced the total limb swelling over 16 days in the polyarthritic phase compared to the arthritic control. These observations were supported by the radiograph records and the histological investigations of the hind limbs which showed reduced bone damage in both PLE and geraniin-treated rats. Conclusion: The findings may confirm the ethnobotanical use of PLE in the management of inflammatory disorders or conditions and observed anti-inflammatory property of PLE may largely be due to its major constituent, geraniin. (C) 2016 Elsevier Ireland Ltd. All rights reserved.