The anti-arthritic effects of Aconitum vilmorinianum, a folk herbal medicine in Southwestern China

Ethnopharmacological relevance: Aconiti Radix (AC) and Aconiti Kusnezoffii Radix (AK) are two traditional Chinese medicines commonly used to treat joint pain and arthritis. In Southwestern China, Huangcaowu (AV), the root of Aconitum vilmorinianum Kom., has long been used as a local substitute for these herbs for analgesia and anti-inflammation. However, its anti-arthritic effects have not been investigated. Aim of study: To investigate the anti-arthritic effects of Huangcaowu (AV). Materials and methods: Mono-arthritis in SD rats was induced by unilateral intra-articular injection of Freund's complete adjuvant. Physiological saline was injected in the contralateral knee. Seventy five percent ethanol extracts of AV (10 mg/kg/day and 100 mg/kg/day), AC (100 mg/kg/day) and AK (100 mg/kg/day) were administered to rats by oral gavage for 14 consecutive days (Day -6 to Day 7) while arthritis was induced at the seventh day (Day 0). The anti-arthritic effects of the herbs were assessed by measuring allodynia, swelling, hyperaemia and the vascular permeability of the knee joints. Results: AV (10 mg/kg/day and 100 mg/kg/day), AC (100 mg/kg/day) and AK (100 mg/kg/day) suppressed joint allodynia. AV (10 mg/kg/day and 100 mg/kg/day) and AK (100 mg/kg/day) significantly reduced join swelling and hyperaemia while AC (100 mg/kg/day) did not. AV (100 mg/kg/day) attenuated vascular permeability while AC (100 mg/kg/day) and AK (100 mg/kg/day) showed no improvement. Conclusions: Huangcaowu (AV) significantly improved allodynia, swelling, hyperaemia and vascular permeability in arthritic knee joints. It showed the highest anti-arthritic effects among the three tested Aconitum herbs. (C) 2013 Elsevier Ireland Ltd. All rights reserved.