title: Olopatadine hydrochloride improves dermatitis score and inhibits scratch behavior in NC/Nga mice.
abstract: BACKGROUND
  Control of itch is an important issue in the treatment of atopic dermatitis (AD). Itch is mediated by a variety of pruritogens, including histamine, and promoted by neurite outgrowth in the epidermis of AD patients, probably due to the release of nerve growth factor.
  
  
  OBJECTIVE
  We investigated the effects of orally administered olopatadine hydrochloride (olopatadine) on itching, itching mediators, and neuritogenic action in a mouse model.
  
  
  METHODS
  NC/Nga mice were treated topically with Dermatophagoides farinae body (Dfb) extract twice weekly for 4 weeks to induce AD-like lesions. They were concomitantly given oral olopatadine, distilled deionized water, or topical tacrolimus during the last 2 weeks.
  
  
  RESULTS
  Olopatadine significantly suppressed scratching, improved the dermatitis score, inhibited neurite outgrowth, and decreased the elevated inflammatory markers, growth factors and histamine content in the lesional skin, and serum concentration of Dfb-specific IgE. Notably, olopatadine treatment increased semaphorin 3A expression in the epidermis.
  
  
  CONCLUSIONS
  Our study confirms the pleiotropic effects of olopatadine, i.e. inhibition of inflammation and neurite extension into the epidermis.
authors.affiliation: Department of Dermatology, Course of Integrated Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan. h-murota@derma.med.osaka-u.ac.jp
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Murota
authors.forename: Mostafa Abd
authors.initials: MA
authors.lastname: El-latif
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Tamura
authors.forename: Toru
authors.initials: T
authors.lastname: Amano
authors.forename: Ichiro
authors.initials: I
authors.lastname: Katayama
mesh_terms: D000818:Animals; D016207:Cytokines / Q000032:analysis; D003876:Dermatitis, Atopic / Q000188:drug therapy* / Q000473:pathology; D040001:Dermatophagoides farinae / Q000276:immunology; D003990:Dibenzoxepins / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005260:Female; D039563:Histamine H1 Antagonists, Non-Sedating / Q000627:therapeutic use*; D007073:Immunoglobulin E / Q000097:blood; D051379:Mice; D020932:Nerve Growth Factor / Q000235:genetics; D016501:Neurites / Q000187:drug effects / Q000502:physiology; D000069605:Olopatadine Hydrochloride; D011537:Pruritus / Q000188:drug therapy*; D051381:Rats; D017208:Rats, Wistar; D040121:Semaphorin-3A / Q000235:genetics; D018418:Th2 Cells / Q000276:immunology
chemical_list: D016207:Cytokines; D003990:Dibenzoxepins; D039563:Histamine H1 Antagonists, Non-Sedating; D040121:Semaphorin-3A; D000069605:Olopatadine Hydrochloride; D007073:Immunoglobulin E; D020932:Nerve Growth Factor