Endothelial-to-mesenchymal transition enhances permissiveness to AAV vectors in cardiac endothelial cells.

A major obstacle in inducing therapeutic angiogenesis in the heart is inefficient gene transfer to endothelial cells (ECs). Here, we identify compounds able to enhance the permissiveness of cardiac ECs to adeno-associated virus (AAV) vectors, which stand as ideal tools for in vivo gene delivery. We screened a library of >1,500 US Food and Drug Administration (FDA)-approved drugs, in combination with AAV vectors, in cardiac ECs.

Flt1 produced by lung endothelial cells impairs ATII cell transdifferentiation and repair in pulmonary fibrosis.

Pulmonary fibrosis is a devastating disease, in which fibrotic tissue progressively replaces lung alveolar structure, resulting in chronic respiratory failure. Alveolar type II cells act as epithelial stem cells, being able to transdifferentiate into alveolar type I cells, which mediate gas exchange, thus contributing to lung homeostasis and repair after damage. Impaired epithelial transdifferentiation is emerging as a major pathogenetic mechanism driving both onset and progression of fibrosis in the lung.

Transbronchial lung cryobiopsy and pulmonary fibrosis: A never-ending story?

Background: The diagnostic process of pulmonary fibrosis (PF) is often challenging, requires a collaborative effort of several experts, and often requires bioptic material, which can be difficult to obtain, both in terms of quality and technique. The main procedures available to obtain such samples are transbronchial lung cryobiopsy (TBLC) and surgical lung biopsy (SLB).

Objective: The purpose of this paper is to review the evidence for the role of TBLC in the diagnostic-therapeutic process of PF.

SARS-CoV-2 infection induces DNA damage, through CHK1 degradation and impaired 53BP1 recruitment, and cellular senescence.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the RNA virus responsible for the coronavirus disease 2019 (COVID-19) pandemic. Although SARS-CoV-2 was reported to alter several cellular pathways, its impact on DNA integrity and the mechanisms involved remain unknown. Here we show that SARS-CoV-2 causes DNA damage and elicits an altered DNA damage response.

The Predictive and Prognostic Role of RAS-RAF-MEK-ERK Pathway Alterations in Breast Cancer: Revision of the Literature and Comparison with the Analysis of Cancer Genomic Datasets.

Although gene alterations of the RAS/RAF/MEK/ERK pathway are uncommon in breast cancer, this pathway is frequently activated in breast tumors, implying its role in tumor progression. We describe, after a revision of the literature, the frequency and types of gene alterations affecting this pathway in breast cancer by analyzing some public datasets from cBioPortal. Moreover, we consider their prognostic and predictive impact on treatment response, along with the role of transcriptomic predictors of RAS pathway activation.

Regeneration or Repair? The Role of Alveolar Epithelial Cells in the Pathogenesis of Idiopathic Pulmonary Fibrosis (IPF).

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive interstitial lung disease (ILD) with unknown etiology in which gradual fibrotic scarring of the lungs leads to usual interstitial pneumonia (UIP) and, ultimately, to death. IPF affects three million people worldwide, and the only currently available treatments include the antifibrotic drugs nintedanib and pirfenidone, which effectively reduce fibrosis progression are, unfortunately, not effective in curing the disease. In recent years, the paradigm of IPF pathogenesis has shifted from a fibroblast-driven disease to an epithelium-driven disease, wherein, upon recurrent microinjuries, dysfunctional alveolar type II epithelial cells (ATII) are not only unable to sustain physiological lung regeneration but also promote aberrant epithelial-mesenchymal crosstalk.

Wet-dry-wet drug screen leads to the synthesis of TS1, a novel compound reversing lung fibrosis through inhibition of myofibroblast differentiation.

Therapies halting the progression of fibrosis are ineffective and limited. Activated myofibroblasts are emerging as important targets in the progression of fibrotic diseases. Previously, we performed a high-throughput screen on lung fibroblasts and subsequently demonstrated that the inhibition of myofibroblast activation is able to prevent lung fibrosis in bleomycin-treated mice.

Radiological-pathological signatures of patients with COVID-19-related pneumomediastinum: is there a role for the Sonic hedgehog and Wnt5a pathways?

https://bit.ly/3vxTQde.

The History and Mystery of Alveolar Epithelial Type II Cells: Focus on Their Physiologic and Pathologic Role in Lung.

Alveolar type II (ATII) cells are a key structure of the distal lung epithelium, where they exert their innate immune response and serve as progenitors of alveolar type I (ATI) cells, contributing to alveolar epithelial repair and regeneration. In the healthy lung, ATII cells coordinate the host defense mechanisms, not only generating a restrictive alveolar epithelial barrier, but also orchestrating host defense mechanisms and secreting surfactant proteins, which are important in lung protection against pathogen exposure. Moreover, surfactant proteins help to maintain homeostasis in the distal lung and reduce surface tension at the pulmonary air-liquid interface, thereby preventing atelectasis and reducing the work of breathing.

Persistence of viral RNA, pneumocyte syncytia and thrombosis are hallmarks of advanced COVID-19 pathology.

Background: COVID-19 is a deadly pulmonary disease with peculiar characteristics, which include variable clinical course and thrombophilia. A thorough understanding of the pathological correlates of the disease is still missing.

Methods: Here we report the systematic analysis of 41 consecutive post-mortem samples from individuals who died of COVID-19.

Prolonged Low-Dose Methylprednisolone in Patients With Severe COVID-19 Pneumonia.

Background: In hospitalized patients with coronavirus disease 2019 (COVID-19) pneumonia, progression to acute respiratory failure requiring invasive mechanical ventilation (MV) is associated with significant morbidity and mortality. Severe dysregulated systemic inflammation is the putative mechanism. We hypothesize that early prolonged methylprednisolone (MP) treatment could accelerate disease resolution, decreasing the need for intensive care unit (ICU) admission and mortality.

Epithelial⁻Mesenchymal Transition in the Pathogenesis of Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a serious disease of the lung, which leads to extensive parenchymal scarring and death from respiratory failure. The most accepted hypothesis for IPF pathogenesis relies on the inability of the alveolar epithelium to regenerate after injury. Alveolar epithelial cells become apoptotic and rare, fibroblasts/myofibroblasts accumulate and extracellular matrix (ECM) is deposited in response to the aberrant activation of several pathways that are physiologically implicated in alveologenesis and repair but also favor the creation of excessive fibrosis via different mechanisms, including epithelial⁻mesenchymal transition (EMT).