title: Pioglitazone attenuates allergic inflammation and induces production of regulatory T lymphocytes.
abstract: BACKGROUND
  Peroxisome proliferator-activated receptor gamma (PPAR-gamma) agonists have been shown to be involved in the regulation of allergic inflammatory responses. The molecular mechanisms by which PPAR-gamma activation inhibits the inflammatory process have not been well understood.
  
  
  METHODS
  BALB/c mice received ovalbumin (OVA) sensitization followed by OVA intranasal challenge. Mice in the treatment group received intragastric administration with pioglitazone (PIO; 30 mg/kg) before each OVA challenge. Various allergic responses were then assessed.
  
  
  RESULTS
  The frequencies of sneezing and nose-scratching and eosinophil infiltration decreased significantly in the PIO treatment group compared with the OVA group (p < 0.05). The PIO treatment also showed that the levels of nasal cavity lavage fluid interleukin (IL)-5 and sera OVA-specific immunoglobulin E (IgE) were markedly reduced (p < 0.05). PIO significantly increased the expression of Foxp3 mRNA (p < 0.05) and induced production of regulatory T lymphocyte (p < 0.01) compared with the OVA group.
  
  
  CONCLUSIONS
  Given the potent effectiveness shown by PIO, we conclude that PPAR-gamma agonists deserve investigation as potential therapies for human allergic upper airway inflammation.
authors.affiliation: Department of Otolaryngology–Head and Neck Surgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, China.
authors.forename: Weihua
authors.initials: W
authors.lastname: Wang
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Zhu
authors.forename: Bingwei
authors.initials: B
authors.lastname: Zhu
authors.forename: Zhaoxin
authors.initials: Z
authors.lastname: Ma
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics; D050990:GATA3 Transcription Factor / Q000235:genetics; D007073:Immunoglobulin E / Q000097:blood; D015848:Interleukin-5 / Q000097:blood; D051379:Mice; D008807:Mice, Inbred BALB C; D047495:PPAR gamma / Q000819:agonists*; D000077205:Pioglitazone; D012333:RNA, Messenger / Q000032:analysis; D012221:Rhinitis, Allergic, Perennial / Q000188:drug therapy* / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects* / Q000502:physiology; D045162:Thiazolidinediones / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D050990:GATA3 Transcription Factor; D015848:Interleukin-5; D047495:PPAR gamma; D012333:RNA, Messenger; D045162:Thiazolidinediones; D007073:Immunoglobulin E; D000077205:Pioglitazone