Could Pirfenidone Also be Effective in Treating Intestinal Fibrosis?

Inhibition of urethral stricture by a catheter loaded with nanoparticle/ pirfenidone complexes

Background: Urethral strictures are common injurious conditions of the urinary system. Reducing and preventing urethral strictures has become a hot and challenging topic for urological surgeons and related researchers. In this study, we developed a catheter loaded with nanoparticle/pirfenidone (NP/PFD) complexes and evaluated its effectiveness at inhibiting urethral stricture in rabbits, providing more references for the clinical prevention and reduction of urethral stenosis. Methods: Twelve adult male New Zealand rabbits were selected and divided into the following four groups in a ratio of 1:1:1:1 using the random number table method: Group A, sham; Group B, urethral stricture (US); Group C, US + unmodified catheter; and Group D, US + NP/PFD catheter. On the 30th day after modelling, retrograde urethrography was performed to evaluate urethral stricture formation, and histopathological examination was performed on the tissues of the corresponding surgical site. Meanwhile, changes in the expression level of Transforming growth factor β1 (TGF-β1) in the tissues were detected by immunohistochemistry. Results: The NP/PFD complexes adhered uniformly to the catheter surface. They remained on the surface of the catheter after insertion into the urethra. In addition, the NP/PFD complexes spread into the urethral epithelium 2 weeks after surgery. Ultimately, urethral strictures were significantly reduced with the placement of the NP/PFD complex catheter. Conclusion: Our catheter loaded with NP/PFD complexes effectively delivered PFD to the urethral epithelium through continuous local delivery, thereby reducing fibrosis and stricture after urethral injury, which may be associated with the inhibition of TGF-β1 expression.

Pirfenidone and post-Covid-19 pulmonary fibrosis: invoked again for realistic goals

Pirfenidone (PFN) is an anti-fibrotic drug with significant anti-inflammatory property used for treatment of fibrotic conditions such as idiopathic pulmonary fibrosis (IPF). In the coronavirus disease 2019 (Covid-19) era, severe acute respiratory syndrome 2 (SARS-CoV-2) could initially lead to acute lung injury (ALI) and in severe cases may cause acute respiratory distress syndrome (ARDS) which is usually resolved with normal lung function. However, some cases of ALI and ARDS are progressed to the more severe critical stage of pulmonary fibrosis commonly named post-Covid-19 pulmonary fibrosis which needs an urgent address and proper management. Therefore, the objective of the present study was to highlight the potential role of PFN in the management of post-Covid-19 pulmonary fibrosis. The precise mechanism of post-Covid-19 pulmonary fibrosis is related to the activation of transforming growth factor beta (TGF-β1), which activates the release of extracellular proteins, fibroblast proliferation, fibroblast migration and myofibroblast conversion. PFN inhibits accumulation and recruitment of inflammatory cells, fibroblast proliferation, deposition of extracellular matrix in response to TGFβ1 and other pro-inflammatory cytokines. In addition, PFN suppresses furin (TGFβ1 convertase activator) a protein effector involved in the entry of SARS-CoV-2 and activation of TGFβ1, and thus PFN reduces the pathogenesis of SARS-CoV-2. Besides, PFN modulates signaling pathways such as Wingless/Int (Wnt/β-catenin), Yes-Associated Protein (YAP)/Transcription Co-Activator PDZ Binding Motif (TAZ) and Hippo Signaling Pathways that are involved in the pathogenesis of post-Covid-19 pulmonary fibrosis. In conclusion, the anti-inflammatory and anti-fibrotic properties of PFN may attenuate post-Covid-19 pulmonary fibrosis.

Therapeutic Targeting of Intestinal Fibrosis in Crohn's Disease

Intestinal fibrosis is one of the most threatening complications of Crohn’s disease. It occurs in more than a third of patients with this condition, is associated with increased morbidity and mortality, and surgery often represents the only available therapeutic option. The mechanisms underlying intestinal fibrosis are partly known. Studies conducted so far have shown a relevant pathogenetic role played by mesenchymal cells (especially myofibroblasts), cytokines (e.g., transforming growth factor-β), growth factors, microRNAs, intestinal microbiome, matrix stiffness, and mesenteric adipocytes. Further studies are still necessary to elucidate all the mechanisms involved in intestinal fibrosis, so that targeted therapies can be developed. Although several pre-clinical studies have been conducted so far, no anti-fibrotic therapy is yet available to prevent or reverse intestinal fibrosis. The aim of this review is to provide an overview of the main therapeutic targets currently identified and the most promising anti-fibrotic therapies, which may be available in the near future.