An investigation into the antimalarial effect of methanolic extract of Paullinia pinnata leaves in Plasmodium berghei infected mice and course of infection

Abstract

Aim: The aim of this study was to investigate the antimalarial activity of methanolic leaves extract of Paullinia pinnata on chloroquine- sensitive Plasmodium berghei NK 65 infected mice. Methodology: The curative study was conducted in thirty- six Wistar albino mice of both sexes which were divided into six groups of six animals each. The animals were infected with P.berghei NK 65. Group I was the negative control and received the vehicle (10% DMSO). Group II received no treatment. Groups III and IV were the positive controls and received chloroquine (CQ) (10mg/kg) and artesunate (4 mg/kg)- amodiaquine (lOmg/kg) combination (ACT) respectively. Groups V and VI received lOOmg/kg and 200mg/kg doses of the extract respectively. Administration was done orally once for three or four days for the standard drugs or the extract/ vehicle respectively. The percentage parasitaemia, packcd cell volume (PCV), body weight and death was monitored on days 0, 1, 2, 3, 4 and 11 (7-day post administration). The study of the course of infection of P.berghei was monitored in eighteen Wistar albino mice of both sexes which were similarly grouped, infected and treated for 3 days. Group A received the vehicle (distilled water) only. Group B was treated with CQ (10 mg/kg) and Group C with ACT. The percentage parasitaemia and death was monitored from day 0 to day 30 (27-day post administration). Results: In the curative study, the extract suppressed parasitaemia at both doses on day 4. The group treated with 200mg/kg dose showed a higher percentage chemo suppression though not significant. The course of infection study revealed that recrudescence occurred on day 8 in the CQ treated group which lasted until day 23 after which the recrudescence was lost without rd- treatment. A similar result was observed in the ACT group.