The Molecular Mechanisms underlying the Therapeutic Effect of Berberine in Inflammatory Skin Diseases
Tsugunobu Andoh1* and Tadamichi Shimizu2*
1Department of Pharmacology and Pathophysiology, College of Pharmacy, Kinjo Gakuin University, Aichi 463-8521, Japan
2Department of Dermatology, Faculty of Medicine, University of Toyama, Toyama 930-0194, Japan
Clinical therapy of chronic inflammatory skin diseases such as atopic dermatitis is extremely difficult. Recently, the use of a number of traditional herbal medicines has been attempted to treat these skin diseases. Orengedokuto is a traditional herbal medicine consisting of four crude natural medicines, and in the field of dermatology, it is used to treat skin diseases accompanied by inflammation and pruritus. Our recent animal study showed that berberine, a major component of Orengedokuto, improves skin inflammation and itching in mice with atopy-like dermatitis. Furthermore, we identified EIF3F and MALT1 as factors involved in the suppression of cytokine production by berberine. In addition, berberine also activates AMP-activated protein kinase, which is involved in the expression of inflammatory and anti-inflammatory cytokines. In addition, berberine also attenuates epidermal hyperplasia though the inhibition of CDC6 expression. Taken together, these findings indicate that berberine improves inflammatory skin diseases by controlling gene expression related to both inflammation, anti-inflammation and keratinocyte hyperproliferation.