SEOUL, Korea—Atopic dermatitis (AD) is one of the most pervasive skin diseases, and its incidence is increasing in industrialized countries. Rosmarinic acid (RA)—a secondary metabolite frequently found in herbs, and has anti-inflammatory, antioxidant and anti-microbial effects—suppressed the development of AD-like dermatitis in 2,4-dinitrofluorobenzene (DNFB)-treated NC/Nga mice by reducing IFN-gamma and IL-4 production by activated T cells and total serum IgE levels, according to a recent Korean study (Int Immunopharmacol. April 16, 2011).
Researchers studied whether RA was an effective treatment against DNFB-induced AD-like skin lesions in NC/Nga mice. RA at 1 or 5μM was found to suppress the productions of interferon (IFN)-gamma and interleukin (IL)-4 significantly by activated CD4(+) T cells. Furthermore, an intraperitoneal injection of RA at 10 mg/kg or 50mg/kg significantly inhibited skin lesion development, and ear thickness and total serum IgE level increases in DNFB-treated NC/Nga mice. In addition, intraperitoneal administered RA at 10 mg/kg or 50mg/kg significantly inhibited the infiltrations of CD4(+) T, CD8(+) T and mast cells into DNFB-induced skin lesions in NC/Nga mice.