Polyphenolic Characterization and Anti-Inflammatory Effect of In Vitro Digested Extracts of Echinacea purpurea L. Plant Parts in an Inflammatory Model of Human Colon Cells

Abstract

Echinacea purpurea L. (EP) preparations are globally popular herbal supplements known for their medicinal benefits, including anti-inflammatory activities, partly related to their phenolic composition. However, regarding their use for the management of inflammation-related intestinal diseases, the knowledge about the fate of orally ingested constituents throughout the human gastrointestinal tract and the exposition of in vitro digested extracts in relevant inflammatory models are unknown. This study investigated for the first time the impact of in vitro gastrointestinal digestion (INFOGEST) on the phenolic composition and anti-inflammatory properties of EP extracts from flowers (EF), leaves (EL), and roots (ER) on IL-1β-treated human colon-derived CCD-18Co cells. Among the seven hydroxycinnamic acids identified using HPLC-UV-MS/MS, chicoric and caftaric acids showed the highest concentrations in EL, followed by EF and ER, and all extracts exerted significant reductions in IL-6, IL-8, and PGE2 levels. After digestion, despite reducing the bioaccessibility of their phenolics, the anti-inflammatory effects were preserved for digested EL and, to a lesser extent, for EF, but not for digested ER. The lower phenolic content in digested EF and ER could explain these findings. Overall, this study emphasizes the potential of EP in alleviating intestinal inflammatory conditions and related disorders.

Impact of Lactic Acid Bacteria Fermentation on (Poly)Phenolic Profile and In Vitro Antioxidant and Anti-Inflammatory Properties of Herbal Infusions

“…On the other hand, regarding the anti-inflammatory effects, all herbal infusion showed significant decreases in the production of pro-inflammatory markers (IL-6, IL-8, and PGE2) on IL-1β-induced CCD18-Co human colon myofibroblasts. This is in agreement with previous studies conducted in systemic and colon models where the anti-inflammatory effect was attributed to the phenolic fraction [21,[48][49][50]. After lacto-fermentation with the two strains of L. plantarum, the reduction in all pro-inflammatory markers was preserved, with the exception of a greater reduction for lacto-fermented thyme compared to the corresponding non-fermented one and, to a lesser extent, for the fermented echinacea and rosemary infusions.…”

“…Therefore, increasing the (poly)phenolic content through lactofermentation could preserve its health effects. In this line, a recent study carried out with extracts of different echinacea parts reported that their anti-inflammatory effects were preserved after in vitro gastrointestinal digestion despite a reduction in the concentration of their phenolics in those with higher contents [21]. Regarding the interaction with the microbiota, a higher content of phenolics, included glycosylated forms, which can be cleaved by endogenous or microbial enzymes from gut microbiota to release an absorbable and(or) metabolizable aglycone forms, could favor a higher conversion of phenolic compounds to more biologically active compounds (e.g., ellagic acid to urolithins) [56], as well as the prebiotic effect of the phenolics to positively modulate the gut microbiota [22,57].…”

“…Thus, rosmarinic acid and luteolin derivatives are the main (poly)phenols in rosemary and thyme [17,18], while ellagitannins and ellagic acid are the primary phenolics in pomegranate peel [19]. Additionally, chicoric and caftaric acids are the most abundant in echinacea extracts [20,21]. However, most of these phenolic compounds are poorly absorbed and usually occur as glycosides, considered biologically inactive, and their bioavailability requires the initial hydrolysis of the sugar moiety by intestinal β-glucosidases producing their aglycones.…”

Echinacea purpurea: An overview of mechanism, efficacy, and safety in pediatric upper respiratory infections and otitis media

“…(Aarland et al, 2017;Balciunaite et al, 2020;Burlou-Nagy et al, 2023;Manayi et al, 2015;Miller & Yu, 2004;Petkova et al, 2023) Polysaccharide: Pectin-like polysaccharide Root, aerial part Immunomodulatory, anti-inflammatory, antidiabetic, antioxidant, antimicrobial, anticancer, antifungal, antiviral, gastrointestinal protective, hypoglycemic, hepatoprotective (Burlou-Nagy et al, 2023; Hou et al, 2020; Jiang et al, 2021; Manayi et al, 2015; Petrova et al, 2023; Ren et al, 2023; Xu et al, 2021) Caffeic acid derivatives: Chicoric acid, caftari acid Root, aerial part Immunomodulatory, anti-inflammatory, antioxidant, antimicrobial, anti-tumoral, antiosteoporotic, neuroprotective action (AdebimpeOjo et al, 2024;Ávila-Gálvez et al, 2024;Manayi et al, 2015;Miller & Yu, 2004;Petrova et al, 2023;Tsai et al, 2012) …”