Pharmacodynamic and Pharmacokinetic Evaluation of Soy Lecithin Based Tablet of Boswellic Acid

ABSTRACT

Background: The oleo-gum resin of Boswellia serrata contains pentacyclic triterpenic acids known as Boswellic acids (BAs) that are responsible for the anti-inflammatory and anti-arthritic activities by inhibition of 5-lipoxygenase. Methods: Soylecithin based tablet formulation of an enriched extract of BAs were formulated and evaluated comparatively with the unformulated extract for bioavailability on rabbits and therapeutic efficacy against arthritis on rats targeting two primary constituent 11-keto ?-boswellic acid (KBA) and 3-O-acetyl 11-keto ?-boswellic acid (AKBA). Total BAs content in the enriched fraction was measured and characterized by HPLC analysis. Soy lecithin based tablet of BAs enriched extract was prepared and evaluated for different parameters. Tablets at 160 and 320 mg/kg, and unformulated extract 160 mg/kg was assessed on CFA-induced arthritic rat model and bioavailability was evaluated on the rabbit. Results: Tablet formulation showed two times higher efficacy in increasing hot plate reaction time, reduction in paw volume, and TNF-? levels compared to unformulated extract signifying enhanced systemic absorption and availability of the BAs at the site of action. The tablet at 320 mg/kg dose showed repair of articular surfaces with small areas of erosion and irregularities in the connective tissue. Plasma samples of rabbit showed identified peaks only for KBA. Conclusion: The soy lecithin based tablet of BAs enriched extract at both doses showed higher peak plasma concentration and AUC compared to unformulated enriched extract. The results of the study substantiated higher efficacy and bioavailability of B. serrata gum resin enriched extract in the form of lecithin based tablet formulation.