Time-course transcriptome analysis of a double challenge bleomycin-induced lung fibrosis rat model uncovers ECM homoeostasis-related translationally relevant genes.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is an irreversible disorder with a poor prognosis. The incomplete understanding of IPF pathogenesis and the lack of accurate animal models is limiting the development of effective treatments. Thus, the selection of clinically relevant animal models endowed with similarities with the human disease in terms of lung anatomy, cell biology, pathways involved and genetics is essential. The bleomycin (BLM) intratracheal murine model is the most commonly used preclinical assay to evaluate new potential therapies for IPF. Here, we present the findings derived from an integrated histomorphometric and transcriptomic analysis to investigate the development of lung fibrosis in a time-course study in a BLM rat model and to evaluate its translational value in relation to IPF. METHODS: Rats were intratracheally injected with a double dose of BLM (days 0-4) and sacrificed at days 7, 14, 21, 28 and 56. Histomorphometric analysis of lung fibrosis was performed on left lung sections. Transcriptome profiling by RNAseq was performed on the right lung lobes and results were compared with nine independent human gene-expression IPF studies. RESULTS: The histomorphometric and transcriptomic analyses provided a detailed overview in terms of temporal gene-expression regulation during the establishment and repair of the fibrotic lesions. Moreover, the transcriptomic analysis identified three clusters of differentially coregulated genes whose expression was modulated in a time-dependent manner in response to BLM. One of these clusters, centred on extracellular matrix (ECM)-related process, was significantly correlated with histological parameters and gene sets derived from human IPF studies. CONCLUSIONS: The model of lung fibrosis presented in this study lends itself as a valuable tool for preclinical efficacy evaluation of new potential drug candidates. The main finding was the identification of a group of persistently dysregulated genes, mostly related to ECM homoeostasis, which are shared with human IPF.

Optimization of M3 Antagonist-PDE4 Inhibitor (MAPI) Dual Pharmacology Molecules for the Treatment of COPD.

Aiming at the inhaled treatment of pulmonary diseases, the optimization process of the previously reported MAPI compound 92a is herein described. The project was focused on overcoming the chemical stability issue and achieving a balanced bronchodilator/anti-inflammatory profile in rats in order to be confident in a clinical effect without having to overdose at one of the biological targets. The chemical strategy was based on fine-tuning of the substitution pattern in the muscarinic and PDE4 structural portions of the dual pharmacology compounds, also making use of the analysis of a proprietary crystal structure in the PDE4 catalytic site. Compound 10f was identified as a chemically stable, potent, and in vivo balanced MAPI lead compound, as assessed in bronchoconstriction and inflammation assays in rats after intratracheal administration. After the in-depth investigation of the pharmacological and solid-state profile, 10f proved to be safe and suitable for development.

Discovery of M3 Antagonist-PDE4 Inhibitor Dual Pharmacology Molecules for the Treatment of Chronic Obstructive Pulmonary Disease.

In this paper, we report the discovery of dual M3 antagonist-PDE4 inhibitor (MAPI) compounds for the inhaled treatment of pulmonary diseases. The identification of dual compounds was enabled by the intuition that the fusion of a PDE4 scaffold derived from our CHF-6001 series with a muscarinic scaffold through a common linking ring could generate compounds active versus both the transmembrane M3 receptor and the intracellular PDE4 enzyme. Two chemical series characterized by two different muscarinic scaffolds were investigated. SAR optimization was aimed at obtaining M3 nanomolar affinity coupled with nanomolar PDE4 inhibition, which translated into anti-bronchospastic efficacy ex vivo (inhibition of rat trachea contraction) and into anti-inflammatory efficacy in vitro (inhibition of TNFα release). Among the best compounds, compound 92a achieved the goal of demonstrating in vivo efficacy and duration of action in both the bronchoconstriction and inflammation assays in rat after intratracheal administration.