Myricetin (MYR) and dihydromyricetin (DHM) are classified as natural flavonoids. Both substances are known for their anti-inflammatory and antioxidant properties. In this study, an in vitro model of inflammation was demonstrated on monolayers of scratched fibroblasts or keratinocytes exposed to LPS from Pseudomonas aeruginosa for six hours. MYR and DHM were subsequently applied to the cells for 24 hours at sub toxic concentrations (5-15 µM). Inflammatory parameters were analysed in collected cell medium and lysate after the incubation period using the Enzyme-Linked ImmuneSorbent Assay (ELISA) and Western blot. Both flavonoids inhibit the production of pro-inflammatory cytokines (IL-6, IL-8) in LPS-stimulated skin cells as well as the decreased level of MMP-1 in fibroblasts. However, the application of MYR and DHM dose dependently increased the level of MMP-1 in keratinocytes. In our experiments, we focused on the anti-glycation activity of MYR and DHM, where the higher concentration of MYR seems to be more effective.

• Keywords
• Dihydromyricetin, Inflammation, Myricetin, Skin wound healing,
• MeSH
• Flavonoids pharmacology   MeSH
• Flavonols MeSH
• Wound Healing MeSH
• Lipopolysaccharides * MeSH
• Matrix Metalloproteinase 1 * MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• dihydromyricetin MeSH Browser
• Flavonoids MeSH
• Flavonols MeSH
• Lipopolysaccharides * MeSH
• Matrix Metalloproteinase 1 * MeSH
• myricetin MeSH Browser

Nanoparticles are utilized in a wide range of industries. The most studied silver nanoparticles (AgNPs) are used in medicine and also in several wound dressings due to their antimicrobial properties. The inflammatory response or potential morphological changes of skin cells after their application are not well known yet. In our study we used the model of human reconstructed epidermis (RHE), prepared in our laboratory, to evaluate whether the AgNPs penetrate through RHE, induce some morphological changes of keratinocytes or influence the production of pro-inflammatory cytokines (IL-6 and IL-8). After the application of three different concentrations (25 ppm, 2.5 ppm, 0.25 ppm) of AgNPs to of RHE for 24 hours we verified that AgNPs did not affect the production of pro-inflammatory cytokines (IL-6 and IL-8) and neither did they influence the expression of keratin K14 and loricrin. The morphology of the cells was likewise unchanged. Based on these results we conclude that AgNPs do not have any negative effect on the morphological changes and do not increase the production of pro-inflammatory cytokines.

• Keywords
• AgNPs, IL-6, IL-8, human reconstructed epidermis, keratin K14, loricrin,
• Publication type
• Journal Article MeSH