Ginsenoside F2-Mediated Intestinal Microbiota and Its Metabolite Propionic Acid Positively Impact the Gut–Skin Axis in Atopic Dermatitis Mice

in the intestines. Pa inhibits inflammatory responses in the gut and skin of AD mice through the G-protein-coupled receptor43/NF-κB pathway, thereby improving skin AD symptoms. These results revealed, for the first time, the mechanism by which ginsenoside F2 improves AD through the Pa (a metabolite of intestinal microbiota)-gut-skin axis.