title: Cortistatin is dysregulated in skin tissue of patients with psoriasis vulgaris and suppresses keratinocyte proliferation in vitro.
abstract: BACKGROUND
  Psoriasis is characterized by the unregulated proliferation of epidermal keratinocytes and increased expression of proinflammatory mediators in the skin. Cortistatin, an endogenous cyclic neuropeptide, inhibits the proliferation of inflammatory cells. We investigated the expression of cortistatin in patients with psoriasis vulgaris and examined its effects on keratinocyte growth in vitro.
  
  
  METHODS
  Serum levels of cortistatin were determined by enzyme-linked immunosorbent assay (ELISA) in 72 patients with psoriasis vulgaris and 76 age-matched healthy volunteers. Cortistatin expression was also examined by immunohistochemistry of skin biopsies from 14 patients and 14 healthy subjects. The effects of cortistatin on the proliferation of primary keratinocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and BrdU incorporation assay. Intracellular levels of cAMP in keratinocytes in the presence or absence of cortistatin were determined by ELISA.
  
  
  RESULTS
  Serum levels of cortistatin and expression levels in skin were significantly lower in patients with psoriasis than in healthy subjects. Cortistatin inhibited keratinocyte proliferation in vitro in a dose-dependent manner and substantially reduced intracellular cAMP levels in keratinocytes.
  
  
  CONCLUSIONS
  Cortistatin is downregulated in the skin of patients with psoriasis vulgaris and suppresses keratinocyte growth in vitro.
authors.affiliation: Department of Dermatology, Xiang-Ya Hospital, Central South University, Changsha, China.
authors.forename: Dai
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Dermatology, Xiang-Ya Hospital, Central South University, Changsha, China.
authors.forename: Hui-Lan
authors.initials: HL
authors.lastname: He
authors.affiliation: Department of Dermatology, Xiang-Ya Hospital, Central South University, Changsha, China.
authors.forename: Ming-Zhu
authors.initials: MZ
authors.lastname: Yao
authors.affiliation: Department of Dermatology, Xiang-Ya Hospital, Central South University, Changsha, China.
authors.forename: Ming-Liang
authors.initials: ML
authors.lastname: Chen
authors.affiliation: Department of Dermatology, Xiang-Ya Hospital, Central South University, Changsha, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D005260:Female; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009479:Neuropeptides / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology*; D011565:Psoriasis / Q000097:blood / Q000378:metabolism*; D012867:Skin / Q000378:metabolism; D055815:Young Adult
chemical_list: D009479:Neuropeptides; C099323:cortistatin; D000242:Cyclic AMP