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Biology subjects

Aidinis, V.

Publications and source records attributed to Aidinis, V..

5 recordsLinked to original sources

An aerosolised dual-action Autotaxin inhibitor- PPARγ agonist for the treatment of pulmonary fibrosis

Fibrosis is a significant mortality factor and health concern, promoting organ malfunction as well as immune and chemical resistance. Among the different fibroproliferative diseases, idiopathic pulmonary fibrosis (IPF) is a fatal fibrotic interstitial lung disease (ILD) with limited therapeutic options. Autotaxin (ATX), an established therapeutic target in IPF, is a secreted lysophospholipase D that catalyses the extracellular production of lysophosphatidic acid (LPA), a growth factor-like signalling phospholipid. The many pathologic effects of LPA in the lung include the suppression of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), a therapeutic target in metabolic disorders, which are frequent comorbidities of IPF associated with unfavourable prognosis. In this report, we introduce EL244, the first-in-class dual ATX inhibitor and PPAR{gamma} agonist, which is endowed with drug-like properties. Developed through chemoinformatic repositioning, innovative rational design, targeted synthesis and pharmacological characterization, EL244 exhibited favourable ADMET and PK/PD profiles. Remarkably, EL244 inhalation, which alleviates systemic toxicity concerns, decreased pulmonary LPA levels and related effects in pulmonary cells, and attenuated bleomycin (BLM)-induced pulmonary fibrosis, restoring respiratory functions. Therefore, EL244 emerges as a promising candidate for the inhaled treatment of IPF and ILDs.

pathology↗

ERAP1 activity modulates the immunopeptidome but also affects the proteome, metabolism and stress responses in cancer cells

Endoplasmic reticulum (ER) aminopeptidase 1 (ERAP1) metabolizes peptides inside the ER and shapes the peptide repertoire available for binding to Major Histocompatibility Complex Class I molecules (MHC-I). Moreover, it may have additional effects on cellular homeostasis, which have not been explored. To address these questions, we used both genetic silencing of ERAP1 expression as well as treatment with a selective allosteric ERAP1 inhibitor to probe changes in the immunopeptidome and proteome of the A375 melanoma cancer cell line. We observed significant immunopeptidome shifts with both methods of functional ERAP1 disruption, which were distinct for each method. Both methods of inhibition led to an enhancement, albeit slight, in tumor cell killing by stimulated human PBMCs and in significant proteomic alterations in pathways related to metabolism and cellular stress. Similar proteomic changes were also observed in the leukemia cell line THP-1. Biochemical analyses suggested that ERAP1 inhibition affected sensitivity to ER stress, reactive oxygen species production and mitochondrial metabolism. Although the proteomics shifts were significant, their potential in shaping immunopeptidome shifts was limited since only 15.8% of differentially presented peptides belonged to proteins with altered expression and only 5.0% of proteins with altered expression were represented in the immunopeptidome shifts. Taken together, our findings suggest that modulation of ERAP1 activity can generate unique immunopeptidomes, mainly due to altered peptide processing in the ER, but also induce changes in the cellular proteome and metabolic state which may have further effects on tumor cells.

biochemistry↗

SRC-mediated and TKS5-enabled podosome formation is an inherent property of IPF fibroblasts, promoting ECM invasion and pulmonary fibrosis

The activation and accumulation of lung fibroblasts (LFs), resulting in aberrant deposition of collagens and other extracellular matrix (ECM) components, is a pathogenic hallmark of Idiopathic Pulmonary Fibrosis (IPF), a lethal and incurable disease. In this report, increased expression of TKS5, a scaffold protein essential for the formation of podosomes, was detected in the lung tissue of IPF patients and bleomycin (BLM)-treated mice, correlating with increased collagen type I alpha 1 chain (COL1A1) expression. The profibrotic milieu, TGF{beta}, as well as a stiff Col1a1-rich acellular fibrotic ECM, were found to induce TKS5 expression and the formation of prominent podosome rosettes in LFs, culminating in increased ECM invasion. Podosomes were retained ex vivo in the absence of any stimulation, indicating that the formation of TKS5-enabled podosomes is an inherent property of IPF LFs. Remarkably, haploinsufficient Tks5+/- mice were relatively resistant to BLM-induced pulmonary fibrosis. Disease protection was largely attributable to diminished podosome formation in LFs and decreased ECM invasion, thus indicating TKS5-enabled and podosome-mediated ECM invasion as a major pathogenic mechanism in pulmonary fibrosis. Expression profiling revealed an ECM-podosome cross talk, and pharmacologic connectivity map analysis suggested several inhibitors that could prevent podosome formation and thus pulmonary fibrosis. Among them, inhibition of src kinase was shown to potently attenuate podosome formation in LFs, ECM invasion, as well as pulmonary fibrosis in post BLM precision cut lung slices, suggesting that pharmacological targeting of TKS5-enabled podosome formation is a very promising therapeutic option in pulmonary fibrosis.

molecular biology↗

Genetic deletion of Autotaxin from CD11b+ cells decreases the severity of experimental autoimmune encephalomyelitis

Autotaxin (ATX) is a secreted lysophospholipase D catalyzing the extracellular production of lysophosphatidic acid (LPA), a growth factor-like signaling lysophospholipid. ATX and LPA signaling have been incriminated in the pathogenesis of different chronic inflammatory diseases and various types of cancer. In this report, deregulated ATX and LPA levels were detected in the spinal cord and plasma of mice during the development of experimental autoimmune encephalomyelitis (EAE). Among the different sources of ATX expression in the inflamed spinal cord, F4/80+CD11b+ cells, mostly activated macrophages and microglia, were found to express ATX, further suggesting an autocrine role for ATX/LPA in their activation, an EAE hallmark. Accordingly, ATX genetic deletion from CD11b+ cells attenuated the severity of EAE, thus proposing a pathogenic role for the ATX/LPA axis in neuroinflammatory disorders.

immunology↗

Dual airway and alveolar contributions to adult lung homeostasis and carcinogenesis

Lung adenocarcinoma (LUAD) and chronic lung diseases caused by smoking and environmental noxious agents are the deadliest diseases worldwide, sharing a partially charted pathobiology of dysfunctional alveolar repair. Here we sought to identify the respiratory epithelial dynamics and molecular signatures participating in adult lung maintenance and chemical carcinogenesis. We employed novel mouse models of respiratory epithelial marking and ablation, a battery of pulmonary toxins and carcinogens, experimental protocols of carcinogen-induced LUAD, tobacco carcinogen-induced LUAD cell lines, and human transcriptomic data and identified a prominent involvement of airway molecular programs in alveolar maintenance and carcinogen-induced LUAD. The airway-specific transcriptomic signature was redistributed to the alveoli after toxic and carcinogenic insults and resulted in marked contributions of airway-labeled cells to injury-recovered alveoli and LUAD. Airway cells maintained Kras mutations and therefore possibly contributed to lung cancer initiation, while LUAD were spatially linked to neighboring airways. Transcriptomic profiling of carcinogen-induced murine and human LUAD revealed enrichment in airway signatures, while ablation of airway cells distorted alveolar structure and function and protected mice from LUAD development. Collectively, these results indicate that airway cells and/or transcriptomic signatures are essential for alveolar maintenance and LUAD development.

cancer biology↗