The Activation of Nrf2/HO-1 by 8-Epi-7-deoxyloganic Acid Attenuates Inflammatory Symptoms through the Suppression of the MAPK/NF-κB Signaling Cascade in In Vitro and In Vivo Models

Meconopsis quintuplinervia Regel Improves Cutibacterium acnes-Induced Inflammatory Responses in a Mouse Ear Edema Model and Suppresses Pro-Inflammatory Chemokine Production via the MAPK and NF-κB Pathways in RAW264.7 Cells

BACKGROUND

Acne vulgaris (AV) is a common adolescent skin condition which is mainly caused by Cutibacterium acnes overcolonization and subsequent inflammation.

OBJECTIVE

Our previous studies demonstrated that ethanol extracts of Meconopsis quintuplinervia Regel (EMQ) possess significant antimicrobial properties. However, their protective effects and potential mechanisms against AV remain unclear.

METHODS

In the present study, the EMQ treatment potential for AV was evaluated in a C. acnes-induced mouse ear edema model, and the EMQ anti-inflammatory mechanism was evaluated in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells.

RESULTS

The results showed that EMQ alleviated edema formation and inflammatory cell infiltration in an acne mouse model by suppressing inflammatory cytokines interleukin (IL)-6, IL-1β, and tumor necrosis factor α expression. Moreover, EMQ inhibited the phosphorylation of MAP kinases (MAPKs) such as p38, JNK, and ERK, the phosphorylation and degradation of IκB-α and the nuclear translocation of nuclear factor kappa B (NF-κB) p65 in LPS-induced RAW264.7 cells.

CONCLUSION

These findings suggest the potent anti-inflammatory activity of EMQ is possibly through the regulation of the MAPKs and NF-κB signaling pathways. Inhibition of C. acnes activity combined with a powerful anti-inflammatory effect of EMQ indicated its potential as a novel therapeutic option for AV.

Antioxidant and Wound Healing Bioactive Potential of Extracts Obtained from Bark and Needles of Softwood Species

Interest in the extraction of phytochemical bioactive compounds, especially polyphenols from biomass, has recently increased due to their valuable biological potential as natural sources of antioxidants, which could be used in a wide range of applications, from foods and pharmaceuticals to green polymers and bio-based materials. The present research study aimed to provide a comprehensive chemical characterization of the phytochemical composition of forest biomass (bark and needles) of softwood species (Picea abies L., H. Karst., and Abies alba Mill.) and to investigate their in vitro antioxidant and antimicrobial activities to assess their potential in treating and healing infected chronic wounds. The DPPH radical-scavenging method and P-LD were used for a mechanistic explanation of the biomolecular effects of the investigated bioactive compounds. (+)-Catechin, epicatechin, rutin, myricetin, 4 hydroxybenzoic and p-cumaric acids, kaempherol, and apigenin were the main quantified polyphenols in coniferous biomass (in quantities around 100 µg/g). Also, numerous phenolic acids, flavonoids, stilbenes, terpenes, lignans, secoiridoids, and indanes with antioxidant, antimicrobial, anti-inflammatory, antihemolytic, and anti-carcinogenic potential were identified. The Abies alba needle extract was more toxic to microbial strains than the eukaryotic cells that provide its active wound healing principles. In this context, developing industrial upscaling strategies is imperative for the long-term success of biorefineries and incorporating them as part of a circular bio-economy.

Anti-Inflammatory Effect of Garcinol Extracted from Garcinia dulcis via Modulating NF-κB Signaling Pathway

Garcinia is a significant medicinal plant with many beneficial phytoconstituents, including garcinol. This study investigated the anti-inflammatory effect of garcinol isolated from Garcinia dulcis fruit in LPS-activated THP-1 and Raw 264.7 macrophages. The results demonstrated that the low concentration of garcinol did not alter cell viability. Furthermore, co-incubation of garcinol with LPS inhibited the production of pro-inflammatory cytokines, including TNF-α, IL-8, IL-6, IL-1β, and pro-inflammatory mediators, including iNOS and COX-2 at the mRNA and protein expression levels. Garcinol also decreased the secretion of TNF-α, IL-6, IL-1β, PGE2, and NO. Moreover, the anti-inflammatory effects involved an alteration in the NF-κB signaling pathway. Downregulation of pIKKα/β, pIκBα, and pNF-κB was observed, hence reducing the translocation of pNF-κB from the cytosol into the nucleus, which subsequently decreased the production of pro-inflammatory molecules. Therefore, garcinol isolated from Garcinia dulcis is a potential candidate as an anti-inflammatory agent for inflammation-related disease treatment.