著者

大西 真里子 渡邉 尚子 岡村 勝正 村田 和也 野口 和真 松田 秀秋

出版者

日本生薬学会

雑誌

生薬學雜誌 : shoyakugaku zasshi : the Japanese journal of pharmacognosy (ISSN:13499114)

巻号頁・発行日

vol.66, no.2, pp.71-76, 2012-08-20

参考文献数

20

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Alopecia areata is one of the most common forms of alopecia and an effective treatment strategy has long been wanted. Several studies have shown that interferon-γ (IFN-γ) is implicated in the pathogenesis of alopecia areata. In this manuscript, we report on an in vitro screening method based on the restoration of cell proliferation against the cell growth inhibition induced by IFN-γ. The proliferation of the human squamous-cell-carcinoma cell line DJM-1 was suppressed by treatment of IFN-γ and the cytotoxicity was ameliorated by anti-human IFN-γ antibody. From the screening of ten extracts prepared from crude drugs related to treatments of alopecia and thermal burn, the extract of dried leaves of Ginkgo biloba (GB-ext) showed the most potent activity at 60.5% of inhibition at 100μg/mL among the samples tested. Furthermore, the seasonal transition manner of the rescue activities of GB-ext was investigated to reveal that the activity increased as the leaves grew. Surprisingly, the fallen leaves showed most potent activity. In addition, a preliminary experiment on the mechanism of the activity was performed using reverse transcription-polymerase chain reaction to demonstrate that GB-ext samples suppressed the expression of mRNA for HLA-DRA. These results suggest that the leaves of G. biloba can be a candidate material for the treatment of alopecia areata and the development of an effective screening method was achieved. The identification of the active principle and further investigation on the mechanism of the rescue activity are now underway.