Xiang-Jiang Xie1, Ting-Ting Di1, Yan Wang1, Ming-Xing Wang1, Yu-Jiao Meng1, Yan Lin1, Xiao-Long Xu1, Ping Li1, Jing-Xia Zhao2. 1. Beijing Hospital of Traditional Chinese Medicine, Affiliated With Capital Medical University, Beijing Key Laboratory of Clinic and Basic Research with Traditional Chinese Medicine on Psoriasis, Beijing Institute of Traditional Chinese Medicine, No.23 Mei shu guan Back Road, DongCheng District, Beijing, 100010, China. 2. Beijing Hospital of Traditional Chinese Medicine, Affiliated With Capital Medical University, Beijing Key Laboratory of Clinic and Basic Research with Traditional Chinese Medicine on Psoriasis, Beijing Institute of Traditional Chinese Medicine, No.23 Mei shu guan Back Road, DongCheng District, Beijing, 100010, China. Electronic address: redzjx@163.com.
Abstract
OBJECTIVES: Indirubin (IR) is a bisindole compound extracted from the leaves of Chinese herb Indigo Naturalis. Indigo Naturalis has been widely used in traditional Chinese medicine to treat inflammatory and autoimmune diseases. Psoriasis is a chronic immune-mediated inflammatory skin disease in which γδ T cells play an important role. This study aims to determine the immunoregulatory effects and the underlying mechanisms of Indirubin in psoriasis-related inflammatory responses. METHODS: BALB/c mice with imiquimod (IMQ)-induced psoriasis-like dermatitis were treated with saline (Model), 1 mg/kg methotrexate (MTX) that serves as a positive control, or 12.5, 25 and 50 mg/kg Indirubin(IR) intragastrically. Keratinocytes proliferation, inflammatory cells infiltration, the expression of inflammatory cytokines and Jak/Stat pathway-related proteins in the skin lesion were examined. The abundance of γδ T cells in lymph nodes and spleen was determined by flow cytometry. The IL-17 expression and secretion, and the activation of Jak3/Stat3 pathways in in vitro cultured γδ T cell were tested. RESULTS: Indirubin ameliorated keratinocyte proliferation, reduced the infiltration of CD3+ T cells, IL-17 A-producing γδ T cells, and CD11b+ neutrophils, inhibited the mRNA expression of Il1, Il6, Il23, Il17a and Il22, and the protein expression of Jak/Stat pathway-related molecules in the skin lesion. Indirubin also reduced the abundance of γδ T cell and CCR6+ γδ T cells (the major IL-17 A producer) in spleen and lymph nodes. In cultured γδ T cells, Indirubin inhibited the mRNA expression of Il17a and Ifng, and the secretion of IL-17 A, while suppressed the activation of Jak3/Stat3 pathways. CONCLUSION: Indirubin alleviates IMQ-induced psoriasis-like dermatitis mainly through reducing the inflammatory responses mediated by IL-17 A-producing γδ T cells involving Jak3/Stat3 activation. Our results highlighted the novel mechanisms by which Indirubin ameliorates psoriasis-related inflammatory responses, supporting its therapeutic potential.
OBJECTIVES:Indirubin (IR) is a bisindole compound extracted from the leaves of Chinese herb Indigo Naturalis. Indigo Naturalis has been widely used in traditional Chinese medicine to treat inflammatory and autoimmune diseases. Psoriasis is a chronic immune-mediated inflammatory skin disease in which γδ T cells play an important role. This study aims to determine the immunoregulatory effects and the underlying mechanisms of Indirubin in psoriasis-related inflammatory responses. METHODS: BALB/c mice with imiquimod (IMQ)-induced psoriasis-like dermatitis were treated with saline (Model), 1 mg/kg methotrexate (MTX) that serves as a positive control, or 12.5, 25 and 50 mg/kg Indirubin(IR) intragastrically. Keratinocytes proliferation, inflammatory cells infiltration, the expression of inflammatory cytokines and Jak/Stat pathway-related proteins in the skin lesion were examined. The abundance of γδ T cells in lymph nodes and spleen was determined by flow cytometry. The IL-17 expression and secretion, and the activation of Jak3/Stat3 pathways in in vitro cultured γδ T cell were tested. RESULTS:Indirubin ameliorated keratinocyte proliferation, reduced the infiltration of CD3+ T cells, IL-17 A-producing γδ T cells, and CD11b+ neutrophils, inhibited the mRNA expression of Il1, Il6, Il23, Il17a and Il22, and the protein expression of Jak/Stat pathway-related molecules in the skin lesion. Indirubin also reduced the abundance of γδ T cell and CCR6+ γδ T cells (the major IL-17 A producer) in spleen and lymph nodes. In cultured γδ T cells, Indirubin inhibited the mRNA expression of Il17a and Ifng, and the secretion of IL-17 A, while suppressed the activation of Jak3/Stat3 pathways. CONCLUSION:Indirubin alleviates IMQ-induced psoriasis-like dermatitis mainly through reducing the inflammatory responses mediated by IL-17 A-producing γδ T cells involving Jak3/Stat3 activation. Our results highlighted the novel mechanisms by which Indirubin ameliorates psoriasis-related inflammatory responses, supporting its therapeutic potential.
Authors: Yang Qi-Yue; Zhang Ting; He Ya-Nan; Huang Sheng-Jie; Deng Xuan; Han Li; Xie Chun-Guang Journal: Chin Med Date: 2020-12-14 Impact factor: 5.455