Chemical Characterization of Alphitonia neocaledonica (Schltr.) Guillaumin Bark Extract and Its Anti-Inflammatory Activities.

Alphitonia neocaledonica (Schltr.) Guillaumin is a small forest tree endemic of New Caledonia traditionally used to treat rheumatic pain and dermatoses. Very few studies described biological activities and phytochemical composition of this plant. This study aims to investigate the anti-inflammatory and anti-gout activities of A. neocaledonica bark extract (ANBE) and its chemical composition. Lipopolysaccharide (LPS)-induced phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 macrophages and LPS/monosodium urate (MSU)-treated THP-1 model reproducing gout in vitro were used. Chemical analyses were undertaken using liquid chromatography-high resolution mass spectrometry (LC-HRMS) approaches. Dose-dependent inhibitory effects of ANBE on inflammatory cytokines interleukin-(IL-)1β, IL-6, and tumor necrosis factor-α (TNF-α) were observed. Inhibition of LPS/MSU-dependent IL-1β at 1 and 10 µg/mL was also reported. Chemical analyses by LC-HRMS allowed us to putatively identify some features such as epigallocatechin, iridoid- and flavonoid-glycosides, oligopeptides, and triterpenoids in ANBE. These results provide some cues in favor of traditional uses of ANBE and support the need of further bioactivities and chemical investigations.