title: Catalpol alleviates ovalbumin-induced asthma in mice: Reduced eosinophil infiltration in the lung.
abstract: BACKGROUND
  Radix Rehmanniae Preparata is a traditional Chinese herbal medicine used to treat asthma, and catalpol is one of the main active ingredients in this herb. In the present study, the effects of catalpol on asthma and the underlying mechanism were explored.
  
  
  METHODS
  Mice with ovalbumin (OVA)-induced asthma were given 5 or 10mg/kg catalpol from Day 15 to Day 28 (intraperitoneal injection). Histopathologic changes were detected by Hematoxylin and Eosin staining and Periodic Acid Schiff staining. The levels of IgE, interleukin (IL)-4, IL-5 and eotaxin were measured by ELISA. The numbers of lymphocytes, monocytes, basophils and eosinophils in the bronchoalveolar lavage fluid were determined by Wright-Giemsa staining. The expression and distribution of eotaxin and C-C chemokine receptor 3 (CCR3) were detected by immunohistochemistry and immunofluorescence. The expression of interleukin-5 receptor α (IL-5Rα) was detected by Western blot assay.
  
  
  RESULTS
  Catalpol inhibited OVA-induced inflammation and IgE secretion in the lung. OVA-induced type 2 inflammation was suppressed by catalpol as evidenced by decreased levels of IL-4 and IL-5. Moreover, catalpol inhibited the aberrant eosinophil infiltration in the lungs, and also suppressed OVA-induced elevation of eosinophil chemokine eotaxin and its receptor CCR3. In addition, IL-5Rα expression in the bone marrow cells derived from catalpol-treated asthmatic mice was lower than that from the untreated asthmatic mice.
  
  
  CONCLUSIONS
  Our study demonstrated that catalpol attenuated OVA-induced asthma and inhibit the infiltration of inflammatory cells, especially eosinophils, into the lung. This study suggests that catalpol may become a promising drug for the treatment of asthma.
authors.affiliation: The Second Department of Paediatrics, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: The Second Department of Paediatrics, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China.
authors.forename: Yongzheng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Pharmacy, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China.
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Xu
authors.affiliation: The First Department of Paediatrics, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China.
authors.forename: Junqi
authors.initials: J
authors.lastname: Luan
authors.affiliation: The First Department of Paediatrics, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China.
authors.forename: Shengai
authors.initials: S
authors.lastname: Piao
authors.affiliation: Department of Endemic Disease, the Second Affiliated Hospital of Harbin Medical University, Harbin 150001, People's Republic of China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Chi
authors.affiliation: The Second Department of Paediatrics, the First Affiliated Hospital, Heilongjiang University of Chinese Medicine, Harbin 150040, People's Republic of China. Electronic address: wangh306@sina.com.
authors.forename: Hai
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy*; D002465:Cell Movement / Q000187:drug effects; D054413:Chemokine CCL11 / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D004804:Eosinophils / Q000187:drug effects* / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D015848:Interleukin-5 / Q000378:metabolism; D053666:Interleukin-5 Receptor alpha Subunit / Q000378:metabolism; D057888:Iridoid Glucosides / Q000627:therapeutic use*; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D054397:Receptors, CCR3 / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; C515457:Ccl11 protein, mouse; C515351:Ccr3 protein, mouse; D054413:Chemokine CCL11; D004365:Drugs, Chinese Herbal; D015848:Interleukin-5; D053666:Interleukin-5 Receptor alpha Subunit; D057888:Iridoid Glucosides; D054397:Receptors, CCR3; C527275:interleukin-5- receptor alpha, mouse; D015847:Interleukin-4; C078040:catalpol; D007073:Immunoglobulin E
keywords: Asthma; CCR3; Catalpol; Eosinophils; Eotaxin; IL-5Rα