Tobias Lotts, Kathrin Kabrodt, Johanna Hummel, Dorit Binder, Ingo Schellenberg, Sonja Ständer, Konstantin Agelopoulos
DOI: 10.2340/00015555-3476

Isatis tinctoria L. (woad) has been used in medicine for centuries and has demonstrated anti-inflammatory effects. However, to date, no well-defined extracts with precise analysis of active substances have been developed. The aim of this study was to develop novel extracts of Isatis tinctoria L., and to characterize their active ingredients and anti-inflammatory properties. Various extracts of Isatis tinctoria L. were analysed for their active ingredients, and screened for anti-inflammatory effects using cyclooxygenase-2 activity assays. A petroleum ether extract was found to have the best effects, and was tested in a mouse model of acute allergic contact dermatitis. In the mouse model the petroleum ether extract resulted in significantly reduced ear swelling, oedema and inflammatory cell density. In mouse skin and human keratinocyte cultures, petroleum ether extract inhibited pro-inflammatory cytokine expression. Furthermore, human mast cell degranulation was significantly inhibited in LAD2 cell cultures. In conclusion, novel woad extracts were developed and shown to have anti-inflammatory properties in a contact hypersensitivity animal model and human keratinocytes. The production of such extracts and further characterization of their specific properties will enable determination of their potential dermatological effects in the treatment of inflamed and irritated skin.

The medicinal herb Isatis tinctoria (woad), which has been used in medicine for centuries, has demonstrated anti-inflammatory effects in recent studies. However, to date, no defined extracts with precise characterization of their active substance content have been developed. This study aimed to develop novel well-characterized extracts of woad, and to determine their anti-inflammatory properties in animal and human skin tissues. The production and precise characterization of such extracts will enable evaluation of their potential dermatological use in the treatment of irritated, pruritic skin.

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