A novel BRD4 degrader, ARV-825, attenuates lung fibrosis through senolysis and antifibrotic effect.

BACKGROUND: Recent studies suggest that cellular senescence is related to the pathogenesis of idiopathic pulmonary fibrosis. However, cellular senescence has yet to be targeted therapeutically in clinical practice. ARV825, a recently developed BRD4 degrader, has been reported as a novel senolytic drug. Conversely, it has also been reported that BRD4 regulates the pro-fibrotic gene expression of fibroblasts. Therefore, this study focuses on the senolytic and anti-fibrotic effects of ARV825 and evaluated these effects on lung fibrosis. METHODS: Lung fibroblasts were induced to senescence through serial passage. The expression of senescence markers and pro-fibrotic markers were determined through quantitative PCR or immunoblot analysis. Lung fibrosis was induced in mice through intratracheal administration of bleomycin. Mice treated with ARV825 underwent histological analysis of lung fibrosis using the Ashcroft score. Total lung collagen was quantified through a hydroxyproline assay. Respiratory mechanics analysis was performed using the flexiVent system. RESULTS: For senescent cells, ARV825 induced the expression of an apoptosis marker while reducing the expression of BRD4 and senescence markers. On the other hand, for early passage pre-senescent cells, ARV825 reduced the expression of collagen type 1 and α-smooth muscle actin. In an experimental mouse model of lung fibrosis, ARV825 attenuated lung fibrosis and improved lung function. Immunohistochemical staining revealed a significant decrease in the number of senescent alveolar type 2 cells in lung tissue due to ARV825 treatment. CONCLUSIONS: These results suggest that ARV825 may impact the progressive and irreversible course of fibrotic lung diseases.

A polo-like kinase inhibitor identified by computational repositioning attenuates pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal fibrotic lung disease with few effective therapeutic options. Recently, drug repositioning, which involves identifying novel therapeutic potentials for existing drugs, has been popularized as a new approach for the development of novel therapeutic reagents. However, this approach has not yet been fully utilized in the field of pulmonary fibrosis. METHODS: The present study identified novel therapeutic options for pulmonary fibrosis using a systematic computational approach for drug repositioning based on integration of public gene expression signatures of drug and diseases (in silico screening approach). RESULTS: Among the top compounds predicted to be therapeutic for IPF by the in silico approach, we selected BI2536, a polo-like kinase (PLK) 1/2 inhibitor, as a candidate for treating pulmonary fibrosis using an in silico analysis. However, BI2536 accelerated mortality and weight loss rate in an experimental mouse model of pulmonary fibrosis. Because immunofluorescence staining revealed that PLK1 expression was dominant in myofibroblasts while PLK2 expression was dominant in lung epithelial cells, we next focused on the anti-fibrotic effect of the selective PLK1 inhibitor GSK461364. Consequently, GSK461364 attenuated pulmonary fibrosis with acceptable mortality and weight loss in mice. CONCLUSIONS: These findings suggest that targeting PLK1 may be a novel therapeutic approach for pulmonary fibrosis by inhibiting lung fibroblast proliferation without affecting lung epithelial cells. In addition, while in silico screening is useful, it is essential to fully determine the biological activities of candidates by wet-lab validation studies.

The lymphocyte-specific protein tyrosine kinase-specific inhibitor A-770041 attenuates lung fibrosis via the suppression of TGF-ß production in regulatory T-cells.

BACKGROUND: Lymphocyte-specific protein tyrosine kinase (Lck) is a member of the Src family of tyrosine kinases. The significance of Lck inhibition in lung fibrosis has not yet been fully elucidated, even though lung fibrosis is commonly preceded by inflammation caused by infiltration of T-cells expressing Lck. In this study, we examined the effect of Lck inhibition in an experimental mouse model of lung fibrosis. We also evaluated the effect of Lck inhibition on the expression of TGF-ß1, an inhibitory cytokine regulating the immune function, in regulatory T-cells (Tregs). METHODS: Lung fibrosis was induced in mice by intratracheal administration of bleomycin. A-770041, a Lck-specific inhibitor, was administrated daily by gavage. Tregs were isolated from the lung using a CD4+CD25+ Regulatory T-cell Isolation Kit. The expression of Tgfb on Tregs was examined by flow cytometry and quantitative polymerase chain reaction. The concentration of TGF-ß in bronchoalveolar lavage fluid (BALF) and cell culture supernatant from Tregs was quantified by an enzyme-linked immunosorbent assay. RESULTS: A-770041 inhibited the phosphorylation of Lck in murine lymphocytes to the same degree as nintedanib. A-770041 attenuated lung fibrosis in bleomycin-treated mice and reduced the concentration of TGF-ß in BALF. A flow-cytometry analysis showed that A-770041 reduced the number of Tregs producing TGF-ß1 in the lung. In isolated Tregs, Lck inhibition by A-770041 decreased the Tgfb mRNA level as well as the concentration of TGF-ß in the supernatant. CONCLUSIONS: These results suggest that Lck inhibition attenuated lung fibrosis by suppressing TGF-ß production in Tregs and support the role of Tregs in the pathogenesis of lung fibrosis.

Neuropsychiatric systemic lupus erythematosus with cerebellar vasculitis and obstructive hydrocephalus requiring decompressive craniectomy.

A 36-year-old woman who had been diagnosed with systemic lupus erythematosus (SLE) was admitted to our hospital due to increasing disease SLE activity. Despite the intensification of immunosuppressive treatment, headache newly developed and worsened. Magnetic resonance imaging (MRI) revealed spreading of a high-intensity area along the sulci of the bilateral cerebellar hemispheres. She was diagnosed with neuropsychiatric SLE and methylprednisolone (mPSL) pulse therapy was started. However, consciousness disorder due to cerebellar oedema with obstructive hydrocephalus appeared and required decompressive craniectomy. The histological findings of the biopsy specimens from cerebellar vermis were compatible with features of vasculitis. She was successfully treated adding intravenous cyclophosphamide therapy.

[Significance of Allowing Pharmacy Students to Attend Visits to Home Care Patients].

In 2006, with the admission of a new batch of students, pharmaceutical education became a 6-year course. This was a result of the urgent need to train a new generation of pharmacists to respond to increasingly advanced and intricate medical care as well as the specific need to coordinate with multiple occupational categories. Meanwhile, with Japan becoming an aged society, medical care has undergone functional differentiation, and home care is now being promoted. As part of an 11- week practical course for 5th-year practical training, students attended visits to home care patients from an early stage, making it possible for them to be present at multiple visits. This was highly significant because it allowed students to experience various disease states of different patients and increase their practical knowledge of pharmaceuticals. This study explores the case example of proposals made by pharmacy students for improving medication-related problems in home care patients during 5th-year practical training.