Anti-Inflammatory Activities of Arnica montana Planta Tota versus Flower Extracts: Analytical, In Vitro and In Vivo Mouse Paw Oedema Model Studies

Abstract

Arnica montana is well known for its anti-inflammatory properties. While the anti-inflammatory activity of Arnica flowers (Arnicae flos) has been extensively studied, that of the whole plant (Arnicae planta tota) is less characterized. We compared the ability of Arnicae planta tota and Arnicae flos extracts to inhibit the pro-inflammatory NF-κB—eicosanoid pathway, using several in vitro and in vivo assays. We showed that Arnicae planta tota inhibited NF-κB reporter activation, with an IC50 of 15.4 μg/mL (vs. 52.5 μg/mL for Arnicae flos). Arnicae planta tota also inhibited LPS-induced expression of ALOX5 and PTGS2 genes in human differentiated macrophages. ALOX5 and PTGS2 encode the 5-lipoxygenase (5-LO) and cyclooxygenase-2 (COX-2) enzymes that initialize the conversion of arachidonic acid into leukotrienes and prostaglandins, respectively. Arnicae planta tota inhibited 5-LO and COX-2 enzymatic activity in vitro and in human primary peripheral blood cells, with lower IC50 compared to Arnicae flos. Finally, Arnicae planta tota applied topically reduced carrageenan-induced mouse paw oedema more efficiently than Arnicae flos. Altogether, Arnicae planta tota displayed a superior anti-inflammatory activity compared to Arnicae flos, suggesting that Arnicae-planta-tota-containing products might be more effective in alleviating the manifestations of acute inflammation than those based on Arnicae flos alone.

Traditional Knowledge Evolution over Half of a Century: Local Herbal Resources and Their Changes in the Upper Susa Valley of Northwest Italy

“…Other natural products typically found in the flower-head are flavonoids such as quercetin and kaempferol, coumarins, and an essential oil [ 31 , 32 ]. A preparation with A. montana showed anti-inflammatory effects in vivo for arthritis [ 33 ]. In particular, helenalin seems to interact with many cysteine residues in a number of target proteins, modifying their activity, such as with NFkB and NFAT, two transcription factors orchestrating the inflammation pathways.…”

Chemical Composition Antioxidant and Anti-Inflammatory Activities of Myrtus communis L. Leaf Extract: Forecasting ADMET Profiling and Anti-Inflammatory Targets Using Molecular Docking Tools

“…Edema is one of the obvious indicators of inflammation and a key factor to take into account when assessing the anti-edematogenic and anti-inflammatory properties of a substance [ 74 ]. Carrageenan is an acknowledged pro-inflammatory agent that has been used to initiate acute inflammatory episodes upon injection into the footpad of rodents, and it well recapitulates the pathogenesis characteristics [ 75 , 76 ]. Carrageenan has been found to resist biodegradation due to its persistence within Kupffer cells for several months [ 9 ].…”

“…Seed extract (50 mg.kg −1 for 2 months) decreased the plasma levels of inflammatory cytokines TNF-α, IL-8, IL-6, and IL-1β as well as erythrocyte concentration, ROS level, and lipid peroxidation, and fortified the activity of the main antioxidant enzymes [ 87 ]. It was reported that phenolic compounds are similar to NSAIDs in their ability to decrease the chemical mediators of inflammation [ 75 ]. We hypothesize that the increased and more varied content of bioactive substances in MMEx explains the higher anti-inflammatory activity by diminishing TNF-α, IL-1β, and COX targets or by blocking the NF-κB pathway and its messengers.…”

Characterization of Phenolic Compounds of Arnica montana Conventional Extracts

“…Recently, there has been a growing interest in this species and its possible industrial applications. Different bioactive compounds have been identified in AM, including sesquiterpene lactones, which are associated with anti-inflammatory properties, and phenolic compounds (mainly phenolic acids and flavonoids), known for their antioxidant and antimicrobial activities [2]. Nowadays, phenolic compounds are one of the most studied groups of bioactive compounds in plants, algae, and foods.…”