Anti-inflammatory properties of Arnica planta tota versus Arnica flos

Arnica montana L. is traditionally indicated for treatment of blunt injuries like tissue damage, strains and bruises that are physiologically accompanied by local inflammatory processes. These include influx of inflammatory immune cells and the release of pro-inflammatory prostaglandins and leukotrienes that are produced by cyclooxygenase 2 (COX-2) and 5-lipoxygenase (5-LOX), respectively, as part of the arachidonic acid (AA) pathway.

The Weleda Arnica 30% ointment contains a unique ethanolic extract from the whole Arnica plant (Arnica planta tota). In contrast, most commercial products comprise extracts from Arnica flowers (Arnica flos) as active pharmaceutical ingredient. Arnica flos contains e. g., sesquiterpene lactones like helenalin or dihydrohelenalin that are known to be active inhibitors of both enzymes. Less is known about the anti-inflammatory efficacy of Arnica planta tota extracts. Thus we aimed to analyze the ethanolic extracts from Arnica planta tota and Arnica flos in terms of inhibition of recombinant human COX-2 and 5-LOX in vitro.

Arnica planta tota and Arnica flos concentration-dependently inhibited 5-LOX activity (IC₅₀: 8.33 µg/ml and 47.0 µg/ml, respectively) and COX-2 activity (IC₅₀: 5.5 µg/ml and 33.1 µg/ml) in vitro. Interestingly, the Weleda Arnica planta tota extract demonstrated superior inhibition of pro-inflammatory and pain-related enzymes in vitro. In this experimental approach the complex mixture of active compounds contained in the complete Arnica plant improved the anti-inflammatory and pain-related efficacy that is already known for Arnica flowers. However, further studies are required to further characterize potential therapeutic advantages of A. planta tota preparations.

Publikationsverlauf

Artikel online veröffentlicht:
13. Dezember 2021