A Single-Dose Treatment of Alstonia boonei Stem Bark Extract Elicits Anti-inflammatory Effect in vivo

Introduction: This study aimed to investigate the anti-inflammatory effect of methanol extract of Alstonia boonei stem bark in a lipopolysaccharide (LPS)-induced model of inflammation.

Methodology: Twenty Wistar albino rats were divided into five groups (n=4). Group 1 served as the normal control, while groups 2-5 were induced with 10 mg/kg b.wt of LPS dissolved in normal saline. Thirty minutes after lipopolysaccharide (LPS) induction, group 3 (standard control) and groups 4 and 5 (Alstonia boonei groups) were treated with the standard drug (50 mg/kg of ibuprofen) and 250 mg/kg and 500 mg/kg (AB₂₅₀ and AB₅₀₀) of the Alstonia boonei extract, respectively. Blood was collected from the animals six hours post-treatment for biochemical analysis.

Results: The acute toxicity study demonstrated a high safety profile of the extract, with an LD₅₀ exceeding 5000 mg/kg body weight in mice. Phytochemical analysis of the Alstonia boonei methanol extract revealed the presence of diverse bioactive compounds, including pomiferin, quercetin, ellagic acid, rutin, coumarin, stilbenes, catechol, and gallic acid, amongst others. The in vivo results showed that the untreated group had a significantly higher (p < 0.05) increase in Interleukin-6 (IL-6), Nuclear factor kappa B-p65 (NFKB-p65), and Interleukin 1 beta (IL-1β) activities in the untreated group compared to the normal control group. In the treatment groups, both doses of the extract (AB₂₅₀ and AB₅₀₀) caused significant reductions in IL-6 and IL-1β levels but not NFKB-p65.

Conclusion: This result highlights the rich bioactive store of A. boonei stem bark and its potential to modulate inflammatory responses in vivo.