Pulmonary fibrosing diseases: A short review and a therapeutic alternative

Pulmonary interstitial diseases are characterized by a wide spectrum of alterations, with idiopathic pulmonary fibrosis (IPF) being one of the most important. Recent studies have shown that COVID-19 can also progress to pulmonary fibrosis. IPF affects elderly individuals, its etiological agent is unknown and its prognosis is poor. Studies have shown an increased incidence and prevalence of IPF, especially in males. Unordered and excessive extracellular matrix deposition is the main lesion of IPF, leading to loss of normal alveolar architecture, decreased pulmonary compliance, and reduced gas exchange. Clinical trials of conventional treatments have not shown significant improvement in patients with IPF, proving the need of more effective alternatives. Studies have shown the association of angiotensin-converting enzyme (ACE)/Angiotensin (Ang)II/AT1 receptor axis with the development of pulmonary fibrosis and hypertension. On the other hand, it was observed that angiotensin 2 converting enzyme (ACE 2)/Angiotensin1-7[Ang-(1-7)]/Mas receptor axis plays an important role in the balance of the ACE/AngII/AT1 axis. In this sense, drugs that increase the activity of the ACE 2/Ang-(1-7)/Mas receptor axis could present therapeutic potential for the treatment of IPF. In addition, when the effects of ACE 2 pharmacological treatment associated with a swimming protocol were analyzed in an experimental model of bleomycin-induced lung lesions, a potent reduction of pulmonary fibrosis and an increase in endurance capacity of animals were observed. Even without fully understanding the mechanisms involved, the results of this study showed that the combination of these two treatment methods might contribute to the treatment of fibrosing interstitial lung diseases.