Long-term complications of COVID-19 with lung injury
EDITORIAL
Abstract
Pulmonary fibrosis is one of the most dangerous long-term complications of COVID-19, especially in patients with severe disease. Some patients who survived severe COVID-19 experienced decreased lung diffusion capacity, ventilation disorders, fibrosis-like changes in lung tissue, chronic dyspnea, and chronic fatigue. The mechanisms of pulmonary fibrosis development include activation of several signaling pathways (TGF-β, Wnt/β-catenin, YAP/TAZ) and the process of epithelial-mesenchymal transition. Transforming growth factor TGF-β plays a central role in the development of fibrosis. Increased TGF-β signaling is associated with alveolar epithelial cell apoptosis, fibroblast activation and myofibroblast formation, induction of epithelial-mesenchymal transition, development of fibrotic changes in the lungs, and is a powerful stimulator of fibrosis. The incidence of pulmonary fibrosis after COVID-19 positively correlates with the severity the acute phase of the disease. Early diagnosis, comprehensive treatment, and rehabilitation play an important role in improving the prognosis for patients with these complications. There is evidence that anti-inflammatory and antifibrotic therapy aimed at suppressing TGF-β may be effective in preventing and reducing the severity of fibrosis. Our review provides methods for the prevention, diagnosis, and treatment of post-COVID pulmonary fibrosis. However, due to the prevalence and high mortality of COVID-19-induced pulmonary fibrosis and the low efficacy of antifibrotic drugs, the development of targeted therapies based on biomarkers and molecular mechanisms of the disease is relevant. Further research is needed to better understand the pathogenesis, identify and use specific biomarkers for diagnosis, prognosis, new treatments, and prevention of post-COVID pulmonary fibrosis.
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