Anti-Inflammatory Effect of Chloroform Fraction of <em>Pyrus Ussuriensis Maxim.</em> Leaf Extract on 2, 4-Dinitrochlorobenzene-Induced Atopic Dermatitis in nc/nga Mice

• Main Authors: KyoHee Cho, Min Cheol Kang, Amna Parveen, Silvia Yumnam, Sun Yeou Kim
• Format: Article
• Language: English
• Published: MDPI AG 2019-01-01
• Series: Nutrients
• Subjects: atopic dermatitis; DNCB-induced-NC/Nga mice; astragalin; TNF-α/IFNγ; IL-6; PULC
• Online Access: https://www.mdpi.com/2072-6643/11/2/276

<i>Pyrus ussuriensis Maxim</i>, a pear commonly known as “Sandolbae” in Korea, is used as a traditional herbal medicine for asthma, cough, and fever in Korea, China, and Japan. <i>P. ussuriensis Maxim</i> leaves (PUL) have therapeutic effects on atopic dermatitis (AD). However, there are no reports on the efficacy of specific components of PUL. In the present study, activity-guided isolation of PUL was used to determine the compounds with potent activity. Astragalin was identified as the major component of the chloroform-soluble fraction of PUL (PULC) using High-performance liquid chromatography (HPLC) analysis. Astragalin and PULC were tested in vitro and in vivo for their effects against AD. PULC and astragalin dose-dependently inhibited the production of nitric oxide (NO) in mouse macrophage (RAW 264.7) cells, and interleukin (IL)-6 and IL-1β in tumor necrosis factor (TNF-α)/interferon γ (IFNγ) induced HaCaT cells. In the AD mice model, PULC and astragalin application significantly reduced dermatitis severity, scratching behavior, and trans-epidermal water loss (TEWL) when compared to that of 2, 4-dinitrochlorobenzene-treated NC/Nga mice. Additionally, they normalized skin barrier function by decreasing immunoglobulin E (IgE) levels in the serum. Filaggrin and involucrin protein levels were normalized by PULC treatment in HaCaT cells and skin lesions. These results indicate that PULC and astragalin ameliorate AD-like symptoms by alleviating both pro-inflammatory cytokines and immune stimuli in vitro and in vivo in animal models. Therefore, PULC and astragalin might be effective therapeutic agents for the treatment of AD.