Small molecule inhibitor of HSP47 prevents pro-fibrotic mechanisms of fibroblasts in vitro.

Excessive extracellular matrix deposition, in particular collagen, is an important cause of lung fibrosis. Heat shock protein 47 (HSP47), a collagen-binding protein, plays an important role in the intracellular processing of procollagen. A small molecule that blocks the collagen chaperone function of HSP47 has been reported as an HSP47 inhibitor. The aim of this study was to assess the effect of the HSP47 inhibitor on collagen synthesis and other fibrotic process in vitro. We evaluated collagen expression by western blot, and determined cell viability and migration by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and scratch test, respectively, in human and mouse lung fibroblasts. Treatment of lung fibroblasts with HSP47 siRNA decreased collagen type I expression. Similarly, the HSP47 inhibitor decreased collagen type I expression in transforming growth factor beta 1 (TGF-ß1)-treated lung fibroblasts in a dose-dependent manner. The inhibitor also decreased the viability and cell migration ability of TGF-ß1-treated lung fibroblasts. Overall, we demonstrated that HSP47 is a potential therapeutic target for pulmonary fibrosis. The small molecule HSP47 inhibitor may mediate antifibrotic effects by suppressing the overexpression of collagen, and inhibiting the viability and migration of fibroblasts. Further research is needed to clarify the therapeutic potential of this HSP47 inhibitor for pulmonary fibrosis.

Pulmonary Nodular Lymphoid Hyperplasia Evaluated with Bronchoalveolar Lavage Fluid Findings: A Case Report and Review of the Literature on Japanese Patients.

Pulmonary nodular lymphoid hyperplasia (PNLH) is a very rare disease, and it is difficult to diagnose PNLH and distinguish it from mucosa-associated lymphoid tissue (MALT) lymphoma. In addition, information on bronchoalveolar lavage fluid (BALF) analyses is lacking. We herein report a 36-year-old Japanese woman diagnosed with PLNH by a surgical biopsy and analysis of BALF. The BALF showed an increase in B-cell marker-positive lymphocytes, normal patterns of B-cell clonality, mucosa-associated lymphoid tissue 1 gene, and immunoglobulin heavy chain at 14q32 translocations. We also reviewed Japanese cases of PNLH described in Japanese or English to explore the characteristics of such cases.

Screening of Inhibitors Targeting Heat Shock Protein 47 Involved in the Development of Idiopathic Pulmonary Fibrosis.

Heat shock protein 47 (HSP47), a collagen-specific molecular chaperone, is causally related to fibrotic diseases, including idiopathic pulmonary fibrosis. The identification of Compounds that interfere with the HSP47-collagen interaction is essential for the development of relevant therapeutics. Herein, we prepared human HSP47 as a soluble fusion protein expressed in E. coli and established an assay system for HSP47 inhibitor screening. We screened a natural and synthetic Compound library established at Nagasaki University. Among 1023 Compounds, 13 exhibited inhibitory activity against human HSP47, of which three inhibited its function in a dose-dependent manner. Epigallocatechin-3-O-gallate, one of these three Compounds, is a typical polyphenol Compound derived from tea leaves. Structurally related Compounds were synthesized and examined for their activity, revealing a hydroxyl group at A-ring position 5 as important for its activity. The present findings provide valuable insight for the development of natural product-derived therapeutics for fibrotic diseases, including idiopathic pulmonary fibrosis.

Removal of an aspirated tooth from the bronchus using a cryoprobe: A case report.

An 88-year-old bedridden man with Alzheimer's disease developed fever and hypoxaemia. Chest radiography showed obstructive pneumonia caused by a foreign body in the airway. Examination using a flexible bronchoscope revealed a silver-crowned molar, thought to have fallen out due to root caries, at the left lower lobe branch. Removal of the foreign body was unsuccessful with grasping or basket forceps, but successful with cryoadhesion using a cryoprobe. Removal of an airway foreign body by a cryoprobe depends on the nature of the foreign body, namely its water content. Therefore, cryoprobes are not inherently suitable for removing foreign bodies of aspirated teeth, but a tooth covered with mucus for a long time after aspiration can be cryoadhered with cryoprobes. Airway foreign bodies that remain in the airway for a long time should also be considered for removal by cryoprobe, regardless of the water content of the material.

Impact of Corticosteroid Administration within 7 Days of the Hospitalization for Influenza Pneumonia with Respiratory Failure: A Propensity Score Analysis Using a Nationwide Administrative Database.

Influenza pneumonia, which causes acute respiratory distress syndrome and multiple organ failure, has no established management protocol. Recently, corticosteroid therapy was used to treat coronavirus disease 2019 with respiratory failure; however, its effectiveness as a treatment for influenza pneumonia remains controversial. To investigate the impact of corticosteroid therapy for the early phase of severe influenza pneumonia, we compared influenza pneumonia patients with respiratory failure treated with or without corticosteroids within 7 days after hospital admission using a Japanese nationwide administrative database. The primary endpoint was the mortality rate. The secondary endpoints were duration of intensive-care unit management, invasive mechanical ventilation, and hospital stay. The inverse probability weighting method with estimated propensity scores was used to minimize the data collection bias. We included 3519 patients with influenza pneumonia with respiratory failure. Of these, 875 were treated with corticosteroids. There was no significant difference between the groups regarding 30-day and 90-day mortality, duration of intensive-care unit management, invasive mechanical ventilation, and hospital stay. However, the in-hospital mortality rate was higher in the corticosteroid group. The use of systematic corticosteroid therapy in patients with influenza pneumonia was associated with a higher in-hospital mortality rate.