14. Title: The inhibitory effect of Sairei-to on hypertrophic scar formation through TGF-β signaling
Hekiko Soen1,2, Akiko Tanabe2, Daisuke Fujita2, Yoshiki Yamashita2, Yoshito Terai2, Hideki Kamegai3, and Masahide Ohmichi2
1:Department of Obstetrics and Gynecology, Dainikyoritu Hospital
2:Department of Obstetrics and Gynecology, Osaka Medical Collage
3:Department of Obstetrics and Gynecology, Suita Saiseikai Hospital
Background: Sairei-to, a Japanese traditional medicine, was noted to be effective for hypertrophic scars in some clinical reports. However, its mechanism of action has not been well defined.
Methods: Fibroblasts were separated from a portion of previous scars of patients with a history of hypertrophic scars and cultured in the presence of serum obtained from healthy adults treated with or without Sairei-to. Proliferation of fibroblasts was evaluated by the MTT assay. TGF-β1 and an extract of Sairei-to were added to serum of cultured normal human dermal fibroblasts (NHDFs). Cell proliferation, the mRNA expression level of connective tissue growth factor (CTGF), and the protein expression levels of phosphorylated Smad2/3 and fibronectin were evaluated.
Result: Proliferation of fibroblasts was significantly suppressed by the serum of patients administered Sairei-to in comparison to the serum of non-treated patients. Proliferation of NHDFs under TGF-β1 stimulation was inhibited by the Sairei-to extract in a concentration-dependent manner. Furthermore, expression of CTGF mRNA, phosphorylated Smad2/3 protein, and fibronectin protein in fibroblasts under TGF-β1 stimulation was suppressed by the Sairei-to extract.
Conclusions: Sairei-to suppressed the proliferation of fibroblasts. The mechanism underlying the growth inhibitory activity of Sairei-to may be the suppression of TGF-β1-induced Smad2/3 phosphorylation.