# Anti-Atopic Dermatitis Activity of _Cornus walteri_ and Identification of the Bioactive Compounds  
[PERSON]  
1 School of Pharmacy, Sungkyunkwan University, Suwon 16419, Korea 1, [PERSON]  
2 Department of Biotechnology, Yonsei University, Seoul 03722, Korea 2, [PERSON]  
3 Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Korea 3, [PERSON]  
1 KIST Gangneung Institute of Natural Products, Natural Product Informatics Research Center, Gangneung 25451, Korea 1, [PERSON]  
4 KIST Gangneung Institute of Natural Products, Natural Product Informatics Research Center, Gangneung 25451, Korea 4, [PERSON]  
2 Department of Biotechnology, Yonsei University, Seoul 08826, Korea 2, 2  
lead to psychological stress, negatively affecting the quality of life [8; 9]. Moreover, there are limited therapeutic options, and the current drugs are mainly immunosuppressive steroids that have various side effects [10]. Therefore, there is a great need to develop novel agents that can suppress the expression of AD mediators.  
_Cornus walteri_ Wanger (Cornaceae), known as \"Walter's dogwood,\" is a deciduous shrub, which is distributed in Asian countries, including China and Korea, and it is utilized as raw material for agricultural tools and high-grade furniture. It has historically been used as a traditional medicine to treat dermatological inflammation caused by lacquer poison [11]. In addition, its leaves have been used as an antidiarrheal in traditional Korean medicine [12]. In previous pharmacological studies, the extract of _C. walteri_ has been found to reduce nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophages [13].  
The leaves of this plant were reported to exhibit protective effects against photoaging induced by UVB in human reconstituted skin [11]. In our continued quest to discover bioactive phytochemicals from natural resources [14; 15; 16; 17; 18; 19], our group investigated the potential bioactive constituents of _C. walteri_ stems (CWS) [20; 21; 22; 23], which have been underdeveloped and underutilized. In our previous studies, it was reported that the MeOH extract of CWS exhibited significant cytotoxic activity [20]; cytotoxic triterpenoids and \(\delta\)-valerolactones were also reported [20; 21; 22]. Recently, we reported that benzyl salicate isolated from the MeOH extract of CWS exhibited nephoprotective effects against nephrotoxicity induced by cisplatin in renal tubular epithelial (LLC-PK1) cells. However, the effects of _C. walteri_ on AD remain largely unknown.  
In this study, we investigated whether the MeOH extract of CWS can ameliorate AD in human keratinocytes. CWS reduces the secretion and gene expression of chemokines and enhances the mRNA expression of the skin structural protein filaggrin [24]. To identify potential bioactive phytochemicals based on the findings of CWS activity, phytochemical analysis of the MeOH extract was performed, which led to the isolation of six constituents (**1-6**), including four triterpenoids, one steroid and one diterpene analog.  
The structures of the isolated compounds (**1-6**) were determined by the interpretation of nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-mass spectrometry (LC/MS) analysis. Additionally, the isolated compounds (**1-6**) were evaluated for their cell viability andotaxin-3 reducing effects on HaCaT cells. Herein, we describe our evaluation of the anti-AD activities of the MeOH extract of _C. walteri_, the isolation and structural elucidation of compounds **1-6** and the identification of bioactive compounds.