Studies on the Anti-Inflammatory Properties of the Aqueous Ethanol Extract of the Stem Bark of Bombax Costatum P.V
The stem bark of Bombax costatum (family: Bombacaceae) is used traditionally in Ghana for the treatment of many inflammatory diseases. The present study evaluated the effect of aqueous ethanol stem bark extract of Bombax costatum on carrageenan-induced paw oedema, cotton-pellet tissue granuloma formation and adjuvant-induced arthritis. The work also established its possible mechanisms of action using clonidine and haloperidol-induced catalepsy, PGE2-induced paw oedema; and determination of serum cytokines levels after acetic acid-induced colitis in rats. Carrageenan-induced foot oedema in chicks was used to assess the effect of the extract on acute inflammation. Extract of Bombax costatum (EBC) showed maximal inhibition of 21.22 ± 1.18 %, 18.39 ± 1.31 % (prophylactic study) at 50 and 100 mg kg-1 and 24.97 ± 1.89 % (curative study) at 100 mg kg-1 respectively. For cotton-pellet granuloma formation; EBC (10-100 mg kg-1) significantly reduced the total granuloma formation in both wet and dry cotton-pellets by 49.01 % and 54.53 % at 100 mg kg-1 respectively. In adjuvant-induced arthritis, EBC significantly inhibited maximal oedema to mean maximal inhibition of 139.49 ± 8.04 %, 136.96 ± 9.71 % and 132.14 ± 12.33 % at 10, 50 and 100 mg kg-1 respectively. Cataleptic responses induced in mice using clonidine was inhibited by EBC with maximal percentage inhibition of 17.50 ± 1.94 % and 12.75 ± 0.85 % at doses of 50 and 100 mg kg-1. EBC reduced the total oedema in PGE2-induced inflammation remarkably by 53.06 % at 100 mg kg-1. EBC reduced total serum levels of IL-6 and TNF-α significantly by 47.32 %, 70.57 % and 37.91 %, 50.32 % at 50 and 100 mg kg-1 respectively. Preliminary phytochemical analysis of aqueous ethanol stem bark extract of Bombax costatum indicated the presence of terpenoids, saponins, tannins, phytosterols, alkaloids, reducing sugars and flavonoids which could possibly be attributed to its anti-inflammatory effects on acute and chronic inflammation.
A thesis submitted to the School of Graduate Studies, Kwame Nkrumah University of Science and Technology in partial fulfillment of the requirements for the award of the Degree of Master of Philosophy, 2016