Exploring the anti-skin inflammation substances and mechanism of Paeonia lactiflora Pall. Flower via network pharmacology-HPLC integration

BACKGROUND: Paeonia lactiflora Pall. (PL) is widely used in China as a homologous plant of medicine and food. PL flower is rich in bioactive substances with anti-inflammatory effects, while the pathogenesis of skin inflammation is complex and the specific mechanism is not clear, the current treatment of skin inflammation is mainly hormonal drugs, and hormonal drugs have obvious toxic side effects. The research on the treatment of skin inflammation by PL flowers is relatively small, so this study provides a basis for the development and utilisation of PL resources. OBJECTIVE: Our study was to investigate the interventional effects of PL flower extracts on skin inflammation and thus to understand its functional role in the treatment of skin inflammation and its molecular mechanisms. METHODS: The major active substances in PL flower extracts were investigated by the HPLC-DAD method, and the potential targets of action were predicted by network pharmacology, which was combined with in vitro experimental validation to explore the mechanism of PL flower extracts on the regulation of skin inflammation. The HPLC-DAD analysis identified seven major active components in PL flower extracts, and in response to the results, combined with the potential mechanism of network pharmacological prediction with skin inflammation, the PL flower extract is closely related to MAPK and NF-κB signaling pathways. In addition, we also investigated the interventional effects of PL flower extract on skin inflammation by western blot detection of MAPK signaling pathway and NF-κB signaling pathway proteins in cells. RESULT: Seven active components were identified and quantified from the extract of PL flowers, including Gallic acid, 1,2,3,4,6-O-Pentagalloylglucose, Oxypaeoniflorin, Paeoniflorin, Albiflorin, Benzoyloxypeoniflorin, and Rutin. It was predicted targets for the treatment of skin inflammation, with PPI showing associations with targets such as TNF, MAPK1, and IL-2. KEGG enrichment analysis revealed that the main signaling pathways involved included MAPK and T cell receptor signaling pathways. Cell experiments showed that the peony flower extract could inhibit the release of NO and inflammatory factors, as well as reduce ROS levels and inhibit cell apoptosis. Furthermore, the extract was found to inhibit the activation of the MAPK and NF-κB signaling pathways in cells. CONCLUSIONS: In this study, we found that PL flower extract can inhibit the production of cell inflammatory substances, suppress the release of inflammatory factors, and deactivate inflammatory signaling pathways, further inhibiting the production of cell inflammation. This indicates that PL flower extract has a therapeutic effect on skin inflammation.