Effect of Aqueous Extract of Alstonia Boonei on Liver Enzymes and Its Anti-Inflammatory Activity on Formalin- Induced Arthritic Wistar Rats

The anti-inflammatory effect of the aqueous extract of Alstonia boonei on the level of liver biomarker in the plasma of normal and arthritic rats was evaluated using the formalin-induced arthritis inflammation tests. Thirty (30) adult female Wister rats were divided into six groups of five rats each. Group 1 as control, group 2(formalin induced group) while groups 3, 4 and 5 were respectively gavage with 150mg/kg, 300mg/kg and 600mg/kg body weight of the extract daily while group 6 was given reference drug( 5mg/kg body weight of indomethacin for 5 days). After formalin treatment, the paw thickness in formalin-induced group was increased compared with control group. The levels of TNF-alpha, CRP, liver enzymes were increased with severe chronic inflammation sign at histopathologically observation. The animals were sacrificed 24hours after the end of treatments, the skin sample of the right paw was taken for TNF alpha evaluation and blood samples were obtained for assay of the levels of ALT, AST, ALP and C-reactive protein(CRP). Liver enzymes were determined using colorimetric methods while TNFalpha and CRP was determined using ELISA technique. Oral administration of the extract produced significant anti-edematogenic, anti-inflammatory activity and dramatic reduction in liver enzymes, TNF alpha and CRP with a dose of 150mg/kg and 300 mg/kg throughout the period of the experiment. This effect of A.boonei at 300mg/kg was similar to indomethacin group which showed a highly significant (p<0.05) inhibition compared to control group.The result of this study suggests that aqueous extract of A. boonei possesses chronic anti-inflammatory activity which may be mediated by either inhibition or by blocking the release of prostaglandins, histamine and pro-inflammatory cytokine (TNF alpha),which suggest that Alstonia boonei is an alternatve approach for treatment of chronic inflammatory disease, thus supporting its usage for anti- inflammatory treatment and potential effect to resuscitate the hepatocytes.