Evaluation Of The Antinociceptive, Antipyretic And Anti-Inflamatory Properties Of Methanolic Bark Extracts Of Terminalia Brownie In Wistar Rats

ABSTRACT

Pain, pyrexia and inflammation cause unnecessary discomfort, suffering and also

lower productivity of the victims. Conventional drugs for these conditions are

expensive, not easily available and have adverse side effects. There is therefore

need to develop alternative therapeutic agents, such as medicinal plant

derivatives, that are cheaper and have lesser side effects. Terminalia brownii is

used in traditional medicine to treat pain, pyrexia, inflammation but there is no

scientific evidence to confirm these ethno-medicinal claims. The present study

therefore tested for the anti-nociceptive, antipyretic and anti-inflammatory

properties of methanolic bark extracts of T brownii in Rattus novegicus. The

plant samples sourced from Kitui County, Kenya were dried and milled at

Kenyatta University Biochemistry department laboratory. Adult male Wistar rats

(R. novegicus), 2-3 months old, weighing 140-180g were divided into six groups

of 5 rats each scheduled for different treatments; normal, negative and positive

controls and three experimental groups (50, 100 and 150mglkg bw extract).

Formalin-induced pain, turpentine oil-induced pyrexia and carrageenan-induced

paw edema were used to assess the anti nociceptive, antipyretic and antiinflammatory

properties of the extract, respectively. The antinociceptive and antiinflammatory

activities of the extract were compared to those of diclofenac while

the antipyretic activity of the extract was compared to that of aspirin. The

phytochemical secondary metabolites tested for include alkaloids, cardiac

glycosides, flavonoids, phenols, saponins, steroids and terpenoids. T brownii

methanolic bark extract demonstrated significant antinociceptive, antipyretic and

anti-inflammatory effects in a dose-dependent manner. The extract at the dose

level of 150mglkg bw exhibited the highest antinociceptive, antipyretic and antiinflammatory

activities and its activities were comparable to those of the

respective reference drugs. The methanolic bark extracts of T brownii reduced

the paw licking time by between 4.62%-44.96% (pSO.05) in the early phase and

35.77%-58.89% (pSO.05) in the late phase. Diclofenac on the other hand reduced

the paw licking time by 44.79% in the early phase and 55.33% in the late phase.

The extract reduced the elevated rectal temperatures by between 1.15%-4.38%

(pSO.05) while aspirin reduced by between 0.00%-4.85%. The extract reduced the

inflamed paw diameter by between 1.57%-20.41 % (pSO.05) while diclofenac

reduced by between 11.12%-25.33%. Phytochemical screening of the extract

indicated the presence of alkaloids, cardiac glycosides, flavonoids, phenols,

saponins, steroids and terpenoids. The present study therefore demonstrated the

antinociceptive, antipyretic and anti-inflammatory properties of methanolic bark

extracts of T brownii hence providing a basis for further research that may result

in pure compounds that can be advanced into drug discovery.