title: Oral administration of Yokukansan inhibits the development of atopic dermatitis-like lesions in isolated NC/Nga mice.
abstract: BACKGROUND
  Increasing evidence suggests that stress can trigger and exacerbate atopic dermatitis (AD). Psychotherapy is becoming more important in the treatment of AD patients. Yokukansan (YKS, Yi-Gan San in Chinese), a traditional Japanese medicine, has been widely utilized in the treatment of neurosis, insomnia and anxiety especially in Asian countries. Furthermore, it was reported that YKS inhibited skin lesions in socially isolated mice but not in group-housed mice. Therefore, in the present study it was investigated whether or not YKS was effective in the treatment of AD using socially isolated NC/Nga mice.
  
  
  OBJECTIVE
  The present study was designed to assess the effect of YKS on the development of AD-like lesions in socially isolated NC/Nga mice to obtain information about its usefulness in the treatment of AD.
  
  
  METHODS
  Ten-week-old male NC/Nga mice were socially isolated under conventional conditions. YKS was administered orally to mice at the dose of 0.5% or 1.0% together with diet. The efficacy of YKS was evaluated by assessing skin lesion severity, scratching behaviors, skin hydration, and infiltration of inflammatory cells in the skin. Grooming behaviors evoked by social isolation stress and serum corticosterone levels were also measured.
  
  
  RESULTS
  Oral administration of YKS to socially isolated NC/Nga mice resulted in the inhibition of exacerbation of AD-like skin lesions. It seemed that the inhibition of exacerbation of AD-like skin lesions observed in NC/Nga mice might be due to suppression of the scratching and grooming behaviors, inhibition of the infiltration of mast cells and eosinophils, and retention of humidity in the skin. Serum corticosterone levels were also significantly inhibited in the 1%-YKS-treated mice as compared with those of the control mice. There were no significant differences in the levels of serum total IgE and nerve growth factor (NGF) between the YKS-treated mice and the non-treated control mice.
  
  
  CONCLUSIONS
  YKS inhibited the development of AD-like skin lesions in socially isolated NC/Nga mice by suppressing scratching and infiltration of inflammatory cells in the skin. These results indicate that YKS possesses an anti-itching property, and its anti-itching may be partly through attenuation on social isolation stress. It is expected that YKS might provide an effective alternative therapy for AD in human patients.
authors: Atopy (Allergy) Research Center, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, 113-8421 Tokyo, Japan. jiangju@juntendo.ac.jp
authors: Ju
authors: J
authors: Jiang
authors: Takuji
authors: T
authors: Yamaguchi
authors: Naoko
authors: N
authors: Funakushi
authors: Takatoshi
authors: T
authors: Kuhara
authors: Ping-shen
authors: PS
authors: Fan
authors: Rie
authors: R
authors: Ueki
authors: Hajime
authors: H
authors: Suto
authors: Yoshio
authors: Y
authors: Kase
authors: Shigaku
authors: S
authors: Ikeda
authors: Hideoki
authors: H
authors: Ogawa
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003345:Corticosterone / Q000097:blood; D003876:Dermatitis, Atopic / Q000188:drug therapy* / Q000473:pathology / Q000523:psychology*; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage*; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D051379:Mice; D020932:Nerve Growth Factor / Q000097:blood; D011537:Pruritus / Q000188:drug therapy* / Q000523:psychology*; D012867:Skin / Q000276:immunology / Q000473:pathology; D012934:Social Isolation / Q000523:psychology
chemical_list: D004365:Drugs, Chinese Herbal; C524644:Yi-Gan San; D007073:Immunoglobulin E; D020932:Nerve Growth Factor; D003345:Corticosterone