Pharmacokinetics of a Natural Self-emulsifying Reversible Hybrid-Hydrogel (N'SERH) Formulation of Full-Spectrum Boswellia serrata Oleo-Gum Resin Extract: Randomised Double-Blinded Placebo-Controlled Crossover Study.

Abstract

The oleo-gum-resin of Boswellia serrata, an Ayurvedic herb for the treatment of chronic inflammatory diseases, contains both volatile (terpenes) and nonvolatile (boswellic acids) molecules as responsible for its bioactivity. The present randomized, double-blinded, placebo-controlled, crossover study evaluated the human pharmacokinetics of a 'natural' hybrid-hydrogel formulation of a unique full-spectrum boswellia extract (BFQ-20) (standardized for both volatile and nonvolatile bioactives) in comparison with unformulated extract (U-BE), for the first time. Mass spectrometry coupled with LC (UPLC-MS/MS) and gas chromatography (GC-MS/MS) measurements of the plasma concentration of boswellic acids and α-thujene at different post-administration time points followed by a single dose (400 mg) of U-BE and BFQ-20, to healthy volunteers (n = 16), offered 4-fold enhancement in the overall bioavailability of boswellic acids from BFQ-20, [area under the curve (AUC) (BFQ-20) = 9484.17 ± 767.82 ng * h/mL vs. AUC (U-BE) = 2365.87 ± 346.89 ng * h/mL], with the absorption maximum (T_max) at 6.3 h post-administration and elimination half-life (T_1/2) of 15.5 h (p < 0.001). While plasma α-thujene was not detectable upon U-BE administration, BFQ-20 provided significant absorption, [AUC (BFQ-20): 298.60 ± 35.48 ng * h/mL; C_max: 68.80 ± 18.60 ng/mL; T_max: 4.12 ± 0.38 h; T_1/2: 16.24 ± 1.12 h]. Further investigation of the anti-inflammatory effect revealed 70.5% inhibition of paw edema in rats compared to 38.0% for U-BE. In summary, the natural self-emulsifying reversible hybrid-hydrogel (N'SERH) formulation of boswellia extract using fenugreek mucilage (FenuMat^®) significantly increased the solubility (58-fold), stability, and bioavailability of both the volatile and non-volatile bioactives which in turn improved the anti-inflammatory efficacy of Boswellia extract.