Targeting Lysyl Oxidase-like 2: A Therapeutic Strategy for Idiopathic Pulmonary Fibrosis with a Novel Indolizine Derivative

Background: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease marked by excessive extracellular matrix (ECM) deposition. Current FDA-approved therapies, such as pirfenidone and nintedanib, offer limited efficacy in halting disease progression. Lysyl oxidase-like 2 (LOXL2) is a key enzyme involved in ECM remodeling and fibrosis. This study investigates Compound #765, a novel indolizine derivative, as a potential LOXL2 inhibitor for IPF treatment. Methods: Compound #765 was synthesized and characterized using spectroscopic methods. Its inhibitory effect on LOXL2 activity was evaluated using LOXL2 enzymatic assays, in vitro fibrosis models with human lung fibroblasts, and in vivo models of pulmonary fibrosis, including bleomycin-treated and TGF-β1-overexpressing transgenic mice. In silico docking studies predicted the binding affinity of Compound #765 to LOXL2. Results: Compound #765 targeted LOXL2 activity and reduced collagen production in lung fibroblasts. In both bleomycin-induced pulmonary fibrosis and TGF-β1-overexpressing murine models, Compound #765 significantly alleviated fibrosis, as indicated by reduced collagen accumulation and inflammatory cell infiltration. The in silico docking studies predicted favorable binding affinity to LOXL2, which was confirmed through in vitro experiments. Importantly, Compound #765 suppressed fibrosis-associated markers in fibroblasts derived from IPF patients, suggesting translational potential. Conclusions: These results demonstrate that Compound #765 functions as a LOXL2 inhibitor with significant anti-fibrotic effects in vitro and in vivo, offering a promising therapeutic approach for IPF and other fibrotic lung diseases.