Effects of angiotensin receptor blockers and angiotensin-converting enzyme inhibitors on respiratory Mucin-5ac, Mucin-C5b and Forkhead box protein-A2 of a hamster tracheal mucosa.

Background: Respiratory mucosal surface is continuously exposed to inhaled pathogens, and a protective layer of secreted mucus acts as the first line of defense against infection through a mechanism called mucociliary clearance. Mucus hypersecretion can negatively affect mucociliary clearance. Although ARBs and ACEIs are associated with induction of cough and angioedema as their side effects, no studies were found that show the effects of these drugs on Mucin-5ac, Mucin-5b, and Forkhead box protein A2. Mucin-5ac and mucin-5b are the main mucins in respiratory mucus and the viscoelasticity properties of respiratory mucus depends on them. Methods: This study used a hamster as an animal model to investigate the effects of ARB and ACEI on respiratory mucin-5ac, mucin-5b, and Forkhead box protein A2. Enalapril and Losartan were used as representative drugs for ACEIs and ARBs, respectively. The concentrations of mucin-5ac, mucin-5b, and Forkhead box protein a2 were measured using ELISA. Dunnet’s t-test was used to analyze the results. Results: Enalapril and Losartan increased mucin-5ac and mucin-5b, but the increase was not significant compared to the control (p > 0.05). However, enalapril and Losartan decreased the concentration of Forkhead box protein a2, but the decrease was not significant compared to the control (p > 0.05). Conclusions: The study found that, administration of enalapril or losartan did not have a significant effect on the concentration of Mucin-5ac, Mucin-5b, and Forkhead box protein A2. Therefore, the administration of these drugs will not reduce mucociliary clearance of the respiratory tract through the impairment of mucus production.