title: The potential effect of the angiotensin II receptor blocker telmisartan in regulating OVA-induced airway remodeling in experimental rats.
abstract: BACKGROUND
  Bronchial asthma is a true ascending clinical problem. Angiotensin II is now accused to be potentially implicated in its pathogenesis, being a potent pro-inflammatory mediator with remodeling effects.
  
  
  OBJECTIVE
  This study aims to evaluate the possible protective effect of telmisartan, an angiotensin II receptor blocker, on experimentally-induced bronchial asthma.
  
  
  METHODS
  Animals were divided into 5 groups; a normal control group, an asthma control group, a reference treatment group, receiving dexamethasone, and two treatment groups, receiving telmisartan in two dose levels. Bronchial asthma was induced by intraperitoneal sensitization followed by intranasal challenge with ovalbumin (OVA). Test agents were administered prior to each intranasal OVA challenge. Lung function tests, namely tidal volume (TV) and peak expiratory flow rate (PEF) were assessed 1h after the last challenge. One day after the last challenge, absolute eosinophil counts (AEC) in blood and bronchoalveolar lavage fluids (BALF) were assessed. Serum immunoglobulin E (IgE) as well as BALF total nitrate/nitrite (NOx) were assessed. Oxidative and inflammatory biomarkers, namely lung tissue superoxide dismutase (SOD), glutathione reduced (GSH), tumor necrosis factor-alpha (TNF-α) and interleukin-5 (IL-5), were also assessed, in addition to histopathological study.
  
  
  RESULTS
  Telmisartan administration in both doses significantly improved TV, PEF, AEC, IgE, NOx, GSH, SOD, TNF-α and IL-5 values compared to asthma control values. Histopathological study strongly supported the results of biochemical estimations, particularly regarding airway remodeling.
  
  
  CONCLUSIONS
  These results suggest that telmisartan may have potential protecting effects against experimental bronchial asthma, probably due to its bronchodilator, antioxidant and anti-inflammatory effects.
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt. Electronic address: dr.mahamohammed@yahoo.com.
authors.forename: Maha M
authors.initials: MM
authors.lastname: Abdel-Fattah
authors.affiliation: Department of Pharmacology, National Research Center, Giza, Egypt.
authors.forename: Abeer A A
authors.initials: AA
authors.lastname: Salama
authors.affiliation: Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, Egypt.
authors.forename: Basim A
authors.initials: BA
authors.lastname: Shehata
authors.affiliation: Department of Pharmacology, National Research Center, Giza, Egypt.
authors.forename: Ismaiel E
authors.initials: IE
authors.lastname: Ismaiel
mesh_terms: D056151:Airway Remodeling / Q000187:drug effects*; D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology*; D000818:Animals; D001249:Asthma / Q000473:pathology / Q000517:prevention & control*; D001562:Benzimidazoles / Q000494:pharmacology*; D001565:Benzoates / Q000494:pharmacology*; D015415:Biomarkers; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D007114:Immunization; D008297:Male; D010047:Ovalbumin / Q000633:toxicity*; D010366:Peak Expiratory Flow Rate / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012129:Respiratory Function Tests; D015842:Serine Proteinase Inhibitors / Q000633:toxicity*; D000077333:Telmisartan; D013990:Tidal Volume / Q000187:drug effects
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D001562:Benzimidazoles; D001565:Benzoates; D015415:Biomarkers; D015842:Serine Proteinase Inhibitors; D010047:Ovalbumin; D000077333:Telmisartan
keywords: Airway remodeling; Angiotensin II; Bronchial asthma; Rat; Telmisartan