Xinyan Han1, Ziyu Chen1, Jinfeng Yuan1, Gaorui Wang1, Xiao Han1, Hui Wu1, Hailian Shi1, Guixin Chou1, Liu Yang2, Xiaojun Wu3. 1. Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education (MOE) Key Laboratory for Standardization of Chinese Medicines, The Sate Administration of TCM (SATCM) Key Laboratory for New Resources and Quality Evaluation of Chinese Medicine. Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China. 2. Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education (MOE) Key Laboratory for Standardization of Chinese Medicines, The Sate Administration of TCM (SATCM) Key Laboratory for New Resources and Quality Evaluation of Chinese Medicine. Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China. Electronic address: yangliu996633@126.com. 3. Shanghai Key Laboratory of Compound Chinese Medicines, The Ministry of Education (MOE) Key Laboratory for Standardization of Chinese Medicines, The Sate Administration of TCM (SATCM) Key Laboratory for New Resources and Quality Evaluation of Chinese Medicine. Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China. Electronic address: xiaojunwu320@126.com.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia annua L. (A. annua) is a traditional Chinese medicine that has been used since ancient times to treat malaria, eczema, dermatomycosis, jaundice, and boils. Modern pharmacological studies show that it has immunosuppressive and anti-inflammatory effects. However, the mechanism of A. annua in the treatment of atopic dermatitis (AD) remains unclear. AIM OF THE STUDY: This study was aimed to investigate the effect of A. annua water extract (AWE) on 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model and tried to explore its possible underlying mechanisms. MATERIALS AND METHODS: AD was induced in BALB/c mice by the topical repeated application of DNCB. Oral drug intervention of AWE and dexamethasone (DEX, positive control) began from the 7th day and continued for 13 consecutive days. The clinical skin score, ear thickness and the weight of ear and spleen were assessed. The ear tissue were stained with toluidine blue and hematoxylin and eosin (H&E) to detect inflammatory cell infiltration. IgE, terleukin (IL)-4 and IL-13 levels in the serum and IgE level in splenocytes were quantified by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of IL-4, IL-6, IL-13, IL-17, tumor necrosis factor (TNF)-α and thymic stromal lymphopoietin (TSLP) were measured by quantitative real time polymerase chain reaction. The phosphorylation levels of mitogen-activated protein kinases (MAPKs)-p38 and nuclear factor (NF)-κB in ear tissue were detected by Western blot. RESULTS: Results demonstrated that AWE treatment significantly attenuated the AD-like symptoms in DNCB-induced BALB/c mice, including the skin dermatitis severity and ear edema. Further study disclosed that AWE treatment suppressed the expressions of IgE, IL-4, IL-6, IL-13, IL-17, TNF-α and TSLP at mRNA and protein levels. Moreover, AWE showed inhibitory effect on the phosphorylation of p38 MAPK and NFκB in ear tissues of AD mice. CONCLUSIONS: Collectively, our results suggested that AWE suppressed DNCB-induced AD in mice probably by restraining Th2 type inflammatory response. These findings might pave the road for the potential clinical application of AWE for AD treatment.
ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia annua L. (A. annua) is a traditional Chinese medicine that has been used since ancient times to treat malaria, eczema, dermatomycosis, jaundice, and boils. Modern pharmacological studies show that it has immunosuppressive and anti-inflammatory effects. However, the mechanism of A. annua in the treatment of atopic dermatitis (AD) remains unclear. AIM OF THE STUDY: This study was aimed to investigate the effect of A. annua water extract (AWE) on 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model and tried to explore its possible underlying mechanisms. MATERIALS AND METHODS: AD was induced in BALB/c mice by the topical repeated application of DNCB. Oral drug intervention of AWE and dexamethasone (DEX, positive control) began from the 7th day and continued for 13 consecutive days. The clinical skin score, ear thickness and the weight of ear and spleen were assessed. The ear tissue were stained with toluidine blue and hematoxylin and eosin (H&E) to detect inflammatory cell infiltration. IgE, terleukin (IL)-4 and IL-13 levels in the serum and IgE level in splenocytes were quantified by enzyme-linked immunosorbent assay (ELISA). The mRNA expression levels of IL-4, IL-6, IL-13, IL-17, tumor necrosis factor (TNF)-α and thymic stromal lymphopoietin (TSLP) were measured by quantitative real time polymerase chain reaction. The phosphorylation levels of mitogen-activated protein kinases (MAPKs)-p38 and nuclear factor (NF)-κB in ear tissue were detected by Western blot. RESULTS: Results demonstrated that AWE treatment significantly attenuated the AD-like symptoms in DNCB-induced BALB/c mice, including the skin dermatitis severity and ear edema. Further study disclosed that AWE treatment suppressed the expressions of IgE, IL-4, IL-6, IL-13, IL-17, TNF-α and TSLP at mRNA and protein levels. Moreover, AWE showed inhibitory effect on the phosphorylation of p38 MAPK and NFκB in ear tissues of AD mice. CONCLUSIONS: Collectively, our results suggested that AWE suppressed DNCB-induced AD in mice probably by restraining Th2 type inflammatory response. These findings might pave the road for the potential clinical application of AWE for AD treatment.