Suppression of thymic stromal lymphopoietin production by rutin in mast cells

Thymic stromal lymphopoietin (TSLP) is a key player in allergic diseases such as asthma and atopic dermatitis. Rutin (RU), a non-nutritive component of many foods, possesses anti-inflammatory, hepatoprotective, and anti-tumour effects. We investigated how RU inhibits the production of TSLP in human mast cell line (HMC-1) cells. RU inhibited the production and mRNA expression of TSLP in HMC-1 cells. The maximal inhibition rate of TSLP production by RU (50 mu M) was 56.25 +/- 2.81%. Nuclear factor-kappa B luciferase activity induced by phorbol myristate acetate plus A23187 was inhibited by RU. In the activated HMC-1 cells, the activation of caspase-1 was increased, whereas the activation of caspase-1 was decreased by pre-treatment with RU. Finally, RU inhibited the numbers of TSLP-positive mast cells in lesions of PMA-induced ear oedema model. These results suggest that RU would be helpful for the treatment of inflammatory and atopic diseases through the inhibition of TSLP. (C) 2012 Elsevier Ltd. All rights reserved.