Abstract

IN VIVO ANTI-INFLAMMATORY AND ANALGESIC PROPRIETIES OF EXTRACTS, FRACTIONS AND POLYSACCHARIDES FROM BRUCEA SUMATRANA ROXB. (SIMAROUBACEAE) LEAVES IN EXPERIMENTAL ANIMALS

Tshodi Ehata M., Nsaka Lumpu S., Lami Nzunzu J., Cimanga Kanyanga R.*, Vlietinck A. J. and Pieters L.

ABSTRACT

The anti-inflammatory and analgesic activities of extracts, fractions and polysaccharides from B. sumatrana leaves collected in Mai-Ndombe in Democratic Republic of Congo (DR-Congo) were evaluated in Wistar rats and reported for the first time in this study. Results indicated that, when tested against carrageenan-induced increase of liquid volume of animal foot (paw edema), lyophilized aqueous extract and its soluble fractions chloroform, ethylacetate, n-butanol and residual aqueous fractions, 80% methanol and total alkaloids extracts, crude and pure polysaccharide fractions, administered at oral doses of 50 and 100 mg/kg body weight respectively, induced significant reduction of paw edema development in dose-dependent manner. At the highest oral dose of 100 mg/kg body weight, they produced percentage inhibitions of carrageenan effects more than 82% for lyophilized aqueous extract, from 65.71±0.02 to 77.42±0.04% for soluble fractions, more than 85% for 80% MeOH and total alkaloids extracts, and ranging between 71.42±0.00 and 91.42±0.01% for polysaccharides compared to negative control (0% inhibition of paw edema). Diclofenac used as anti-inflammatory reference product caused more than 97.14±0.03% inhibition of paw edema development. In analgesic test, acetic acid-induced pains was used to determine the analgesic activity. Results from this assay revealed that, the oral administration of lyophilized aqueous extract and its fractions, 80% methanol and total alkaloids extracts, crude and pure polysaccharide fractions from Brucea sumatrana leaves at 50 and 100 mg/kg body weight caused marked reduction of the number of acetic acid-induced abdominal writhes of treated Wistar rats in dose-dependent manner compared to negative control, indicating significant peripheral antinociceptive activity. All extracts including lyophilized aqueous, 80% methanol and total alkaloids significantly reduced abdominal writhes of the treated animals with percentage reductions ranging from 83 to 86% with the 80% methanol extract as the most active (86.32±0.02%). Chloroform, ethylacetate, n-butanol and residual aqueous soluble fractions also showed good reduction of acetic acid-induced abdominal writhes in treated animals with percentage inhibitions between 67 to 76% with ethylacetate fraction as the most active (76.83±0.03%). Crude and isolated pure polysaccharide fractions provoked prominent reduction of abdominal writhes of treated animals with percentage reductions ranging from 82 to 83% with crude polysaccharide extract as the most active (85.15±0.01%). Aspirin used as reference analgesic drug reduced the number of abdominal writhes by 89.27±0.001%. A number of phytochemical compounds associated with anti-inflammatory and analgesic activities were observed to be present in all tested samples of B. sumatrana leaves. This present study therefore, scientifically confirmed the traditional use of the studied medicinal plant part in the management of various pains in traditional medicine including rheumatism. These results showed that all tested samples from B. sumatrana leaves possessed good and appreciable anti-inflammatory and analgesic effects. They can thus, support the use of the plant part in traditional medicine in painful conditions acting centrally and peripherally in both evaluated biological activities.

Keywords: Brucea sumatrana, leaves, extracts, fractions, polysaccharides, in vivo anti-inflammatory and analgesic activities, paw edema, writhes, Wistar rats.