Minjee Choi1,2, Jun Koo Yi3, Si-Yong Kim1, Jung Hyun Ryu4, Jinhee Lee1, Wookbong Kwon1, Soyoung Jang1, Dongjun Kim1, MyoungOk Kim5, Hyungwoo Kim4, Sung Hyun Kim6, Seong-Kyoon Choi7, Zae Young Ryoo8. 1. School of Life Science, BK21 Plus KNU Creative Bioresearch Group, Kyungpook National University, 80 Daehakro, Bukgu, Daegu, 41566, South Korea. 2. Core Protein Resources Center, DGIST, Daegu, Republic of Korea. 3. Gyeongsangbukdo Livestock Research institute, Yeongju, South Korea. 4. Pusan National University School of Korean Medicine, Busan, South Korea. 5. School of Animal Science Biotechnology, Kyungpook National University, Daegu, South Korea. 6. Department of Bio-Medical Analysis, Korea Polytechnic College, Chungnam, South Korea. 7. Core Protein Resources Center, DGIST, Daegu, Republic of Korea. cskbest@dgist.ac.kr. 8. School of Life Science, BK21 Plus KNU Creative Bioresearch Group, Kyungpook National University, 80 Daehakro, Bukgu, Daegu, 41566, South Korea. jaewoong64@hanmail.net.
Abstract
BACKGROUND: The root bark of Dictamnus dasycarpus Turcz. has been successfully used for the treatment of inflammatory skin conditions such as eczema and pruritus. However, the anti-psoriatic effect of this plant has not until now been investigated. METHODS: The aim of this project was to investigate whether a methanol extract of Dictamnus dasycarpus Turcz. root bark (MEDD) can be used as a therapeutic agent for psoriasis in C57BL/6 mice model of imiquimod (IMQ)-induced psoriasis. IMQ and MEDD was applied to mouse skin continuously for 7 days. The skin phenotype and the levels of inflammatory cytokines, such as interferon (IFN)-γ and interleukin (IL)-17, were analyzed. The immune cell population was determined by flow cytometry, and STAT1 and 3 protein levels were measured. RESULTS: An alleviation of scaly skin phenotype, immune cell infiltration in the dermis, and epidermal hyperplasia was observed after daily MEDD treatment in the lesion-affected area. It was also found that MEDD reduced IL-17 cytokine levels decreased by 44.37% (p < 0.05), the number of IL-17-producing Th17 cells and γδT cells, and the size of the Th1 population secreting IFN-γ decreased by 45.98, 62.21, and 44.42%, respectively (p < 0.05), compared with the vehicle control group. STAT3 signals, associated with IL-17 are also reduced by MEDD. CONCLUSIONS: An anti-psoriatic effect of MEDD was observed, as determined by decreased skin inflammation, reduced number of inflammatory cytokines, and a smaller population of inflammatory cells. These results contribute to the validation of the use of MEDD in the treatment of psoriasis.
BACKGROUND: The root bark of Dictamnus dasycarpus Turcz. has been successfully used for the treatment of inflammatory skin conditions such as eczema and pruritus. However, the anti-psoriatic effect of this plant has not until now been investigated. METHODS: The aim of this project was to investigate whether a methanol extract of Dictamnus dasycarpus Turcz. root bark (MEDD) can be used as a therapeutic agent for psoriasis in C57BL/6 mice model of imiquimod (IMQ)-induced psoriasis. IMQ and MEDD was applied to mouse skin continuously for 7 days. The skin phenotype and the levels of inflammatory cytokines, such as interferon (IFN)-γ and interleukin (IL)-17, were analyzed. The immune cell population was determined by flow cytometry, and STAT1 and 3 protein levels were measured. RESULTS: An alleviation of scaly skin phenotype, immune cell infiltration in the dermis, and epidermal hyperplasia was observed after daily MEDD treatment in the lesion-affected area. It was also found that MEDD reduced IL-17 cytokine levels decreased by 44.37% (p < 0.05), the number of IL-17-producing Th17 cells and γδT cells, and the size of the Th1 population secreting IFN-γ decreased by 45.98, 62.21, and 44.42%, respectively (p < 0.05), compared with the vehicle control group. STAT3 signals, associated with IL-17 are also reduced by MEDD. CONCLUSIONS: An anti-psoriatic effect of MEDD was observed, as determined by decreased skin inflammation, reduced number of inflammatory cytokines, and a smaller population of inflammatory cells. These results contribute to the validation of the use of MEDD in the treatment of psoriasis.
Entities:
Keywords:
Dictamnus dasycarpus; Gamma delta T cell; Inflammation; Psoriasis; Skin; T helper cell