Penta-O-galloyl-β-D-glucose from Paeonia lactiflora Pall. root extract enhances the expression of skin barrier genes via EGR3

Abstract Ethnopharmacoligical relevance Paeonia lactiflora Pall. has long been used to treat inflammatory skin diseases, such as psoriasis. Aim of the study: The skin acts as a barrier and provides protection against various stresses by expressing skin barrier genes during keratinocyte differentiation. However, the effect of Paeonia lactiflora Pall. root extract on the expression of skin barrier genes has not been investigated. Here, we aimed to show that treatment of keratinocytes with Paeonia lactiflora Pall. root can upregulate genes related to keratinocyte differentiation. Materials and methods To determine the effect Paeonia lactiflora Pall. root extract, RNA-Seq, gene ontology, and gene set enrichment analysis were performed. Reverse transcriptase quantitative polymerase chain reaction analysis was performed to confirm the increased expression of skin barrier genes. Results Treatment with Paeonia lactiflora Pall. root enhanced the expression of skin barrier genes, including the filaggrin, loricrin, and involucrin. Moreover, we found that penta-O-galloyl-β-D-glucose (PGG), one of the ingredients in Paeonia lactiflora Pall. root, enhanced the expression of skin barrier genes, by upregulating the expression of the transcription factor EGR3. Conclusions PGG and Paeonia lactiflora Pall. root extract have therapeutic potential for the treatment of diseases related to skin barrier disruption and can be used in cosmetics to enhance skin barrier function.