Anti-inflammatory activity and molecular docking studies of the hydromethanolic leaf extract of Baphia longipedicellata brumitt in rats

Abstract

Background: Almost all Baphia species of the Fabaceae family have a long history in traditional China due to their potent anti-inflammatory properties Baphia longipedicellata (B. longipedicellata) is a relatively novel plant comprised mainly of stigmasterol, which has a rich history in Chinese medicine and is a principal active component in numerous Chinese herbs such as maidong, the banxia-baizhu-tianma decoction and Qingfengteng which are all native to China and well known for its use in inflammatory diseases, asthma and diabetes management.

Aim of the study: The study was meticulously designed to evaluate the anti-inflammatory activity of Baphia longipedicellata in rats. What sets this study apart is its unique approach to predicting the mechanism of anti-inflammatory action through docking studies.

Materials and Methods: Preliminary phytochemical screening and oral acute toxicity were carried out for the hydromethanolic extract of Baphia longipedicellata (HMBL). Phytocompounds in the extract were identified using high-performance Liquid Chromatography (HPLC). Carrageenan and egg albumin-induced paw edema models in rats were evaluated to ascertain the extract's anti-inflammatory potential.

Molecular docking experiments were carried out to evaluate the binding affinity of HPLC-selected compounds to cyclooxygenase-2 (COX-2) and tumour necrosis Factor-alpha (TNF-alpha).

Results and Discussion: Preliminary phytochemical screening revealed the presence of saponin, tannins, cardiac glycosides, alkaloids, terpenoids, etc. Results obtained from this study showed that the LD50 was greater than 2000 mg/kg, and there were no observable toxic effects or mortality following its acute exposure.

HPLC of HMBL profiled, Curcumin, Lutein, Stigmasterol, Beta-Sitosterol, Chrysarobin, Quercetin, and Napabucasin,

HMBL extract at all treatment doses showed a significant reduction in both carrageenan and egg albumin-induced hind paw edema in a dose-dependent manner, comparable to the standard drug Diclofenac. Peak anti-oedematogenic activity was observed at the 6th-hour post-carrageenan injection with 28.50, 42.06, and 36.90 % inhibition for HMBL (100, 200, or 400 mg/kg) and 5th-hour post-egg-albumin injection with 61.22, 66.88, and 48.06 % inhibition.

The molecular docking study showed that all the isolated HPLC compounds inhibited COX-2 and TNF-alpha.

Conclusion Ultimately, the hydro-methanolic leaf extract of B. longipedicellata exhibits potent anti-inflammatory activity via COX 2 and TNF-alpha inhibition. Thus, it would be a viable phytotherapeutic option for treating inflammatory conditions.