Evaluation of in vitro and in vivo anti-arthritic property of Jaundea pinnata (p. Beauv.) G. Schellenb. (Connaraceae) leaf methanol extract and fractions

Abstract

The anti-arthritic effect of crude methanol (MeOH) extract of Jaundea pinnata (Connaraceae) leaf, as well as its dichloromethane (DCM) and aqueous (AQ) fractions, was investigated by both bovine serum albumin and fresh hen’s egg albumin in vitro models. In addition, rats dosed with the MeOH extract and its fractions, and standard anti-arthritic drug, diclofenac sodium^® (50 mg/kg) up to 14 days were investigated for effects on rat paw oedema in a formaldehyde model. Further assessment of anti-arthritic activity was by assessing the alteration of haematological and biochemical parameters by tested agents. Oral administration with methanol extract and fractions up to Day 14 produced progressive reductions in rat paw oedema diameter. DCM fraction was more active than AQ fraction in reducing paw diameter, and was comparable to MeOH extract and standard drug, diclofenac sodium^®. MeOH extract and DCM fraction reduced erythrocyte sedimentation rate (ESR) in a dose-dependent fashion. On haematological parameters, extract gave dosedependent increase only in packed cell volume (PCV) and was comparable to diclofenac sodium^®1000 mg/kg. DCM fraction gave comparable PCV as the standard drug but AQ fraction was less effective. Extract and fractions were comparable to diclofenac sodium^® in haemoglobin count, while neutrophil count was positively affected by extract and DCM fraction as the standard drug. Extract and fractions had no significant effect on white blood cell count. Effect of extract at 1000 mg/kg on liver function parameters (total protein, albumin and alanine aminotransferase) was comparable to that of standard drug. DCM fraction was a better inhibitor of protein denaturation than AQ fraction in both models. Overall, results of this study support the folkloric use of ^{J. pinnata} leaf in treating rheumatoid arthritis.

Keywords: Jaundea pinnata, methanol leaf extract, dichloromethane fraction, anti-arthritic activity, rats.