Abstract: Salicylate-rich plants are an attractive alternative to synthetic anti-inflammatory drugs due
to a better safety profile and the advantage of complementary anti-inflammatory and antioxidant
effects of the co-occurring non-salicylate phytochemicals. Here, the phytochemical value and
biological effects in vitro and ex vivo of the stems of one of such plants, Gaultheria procumbens L., were
evaluated. The best extrahent for effective recovery of the active stem molecules was established in
comparative studies of five extracts. The UHPLC-PDA-ESI-MS3, HPLC-PDA, and UV-photometric
assays revealed that the selected acetone extract (AE) accumulates a rich polyphenolic fraction
(35 identified constituents; total content 427.2 mg/g dw), mainly flavanols (catechins and
proanthocyanidins; 201.3 mg/g dw) and methyl salicylate glycosides (199.9 mg/g dw). The extract
and its model components were effective cyclooxygenase-2, lipoxygenase, and hyaluronidase
inhibitors; exhibited strong antioxidant capacity in six non-cellular in vitro models (AE and
procyanidins); and also significantly and dose-dependently reduced the levels of reactive oxygen
species (ROS), and the release of cytokines (IL-1β, IL-8, TNF-α) and proteinases (elastase-2,
metalloproteinase-9) in human neutrophils stimulated ex vivo by lipopolysaccharide (LPS) and
N-formyl-L-methionyl-L-leucyl-L-phenylalanine (f MLP). The cellular safety of AE was demonstrated
by flow cytometry. The results support the application of the plant in traditional medicine and
encourage the use of AE for development of new therapeutic agents.
Keywords: Gaultheria procumbens; neutrophils; oxidative burst; anti-inflammatory activity;
antioxidant activity; polyphenols; salicylates; procyanidins; interleukin 1β; elastase 2
… Catechin was purchased from Biopurify Phytochemicals Ltd. (Chengdu, Sichuan,
China)…