Glycosylation of proteins of human skin fibroblasts is changed by rosmarinic acid.

Glycosylation is a common post-translational process of protein modification. Glycans participate in many crucial biological functions like cell differentiation, cell adhesion, cell-cell interactions, and regulation of signaling pathways. Rosmarinic acid (RA) is a natural flavonoid with many pharmacological activities including anti-inflammatory, anti-oxidative, anti-bacterial, or anti-fibrotic. In this study, we aimed to determine the effect of 25, 50, and 100 μM rosmarinic acid on specific carbohydrate antigens in human skin fibroblasts. ELISA-liked test with biotinylated lectins was used to assess the level of sugar structures in cell lysates and culture supernatant. RT-PCR was applied to determine mRNA of selected glycosyltransferases responsible for formation of sugar antigens. Rosmarinic acid inhibited the expression of Tn, T antigens and their sialylated forms, fucosylated antigens, di NAclactosamine, and mannose antigens. All used doses of RA significantly decreased core 1 β1-3galactosyltransferase mRNA and 25 and 50 μM acid significantly inhibited GalNAcα2-6-sialyltransferase mRNA. The results indicate that rosmarinic acid, due to decreasing effect on specific sugar antigens, can change some of crucial carbohydrate functions in skin fibroblasts, e.g., involved in cell adhesion and cell-cell interactions.