Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 11 2 2012 06 15 133 145 EN Li Zhang Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Keng Li Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Li-bing Ma Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Su-bo Gong Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Gu-yi Wang Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Yi Liu Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Xiao-ying Ji Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Li Xu Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Shao-kun Liu Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Ping Chen Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Ruo-yun Ouyang Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China Xu-dong Xiang Department of Respiratory Medicine, The Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, China 2015 10 01 In traditional Chinese medicine, arsenous compounds, including arsenic trioxide (ATO), are often used to treat many diseases, which are safe and effective. Recently, studies have indicated that Th17– IL-17 involved in the pathogenesis and development of asthma. The goal of this study was to investigate the effect and mechanism of ATO on asthma, especially the Th17– IL-17 axis. We used oval bumin (OVA)-immunized mice as a model for asthma and treated mice with ATO or dexamethasone. The mice were then monitored airway responsiveness, airway inflammation, mucus production, IL-17 levels in BALF and the positive rate of Th17 cells. In vitro, CD4+ T cells from splenic cell suspensions were separated and purified. We measured the expression of IL-17 and caspase-12 protein in purified CD4+ T cells, and detected IL-17 levels in CD4+  T lymphocyte culture solution with or without ATO. Moreover, apoptosis, mitochondrial membrane potential, cytosolic calcium were analyzed. We found that ATO  could reduce airway responsiveness, airway inflammation, mucus hyperplasia, the expression of IL-17 in BALF and the positive rate of Th17 cells at a level comparable to treatment with DXM. In vitro data suggested that ATO can induce CD4+ T cells apoptosis, cause mitochondrial dysfunction, Ca2+  overload and promote  caspase-12 activation. Our study suggested that ATO had potential medical value for the treatment of human asthma. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/338 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/338/338