Galectin-3-Binding Glycomimetics that Strongly Reduce Bleomycin-Induced Lung Fibrosis and Modulate Intracellular Glycan Recognition.
Delaine, T., Collins, P., MacKinnon, A., Sharma, G., Stegmayr, J., Rajput, V.K., Mandal, S., Cumpstey, I., Larumbe, A., Salameh, B.A., Kahl-Knutsson, B., van Hattum, H., van Scherpenzeel, M., Pieters, R.J., Sethi, T., Schambye, H., Oredsson, S., Leffler, H., Blanchard, H., Nilsson, U.J.(2016) Chembiochem 17: 1759-1770
- PubMed: 27356186 
- DOI: https://doi.org/10.1002/cbic.201600285
- Primary Citation of Related Structures:  
5E88, 5E89, 5E8A - PubMed Abstract: 
Discovery of glycan-competitive galectin-3-binding compounds that attenuate lung fibrosis in a murine model and that block intracellular galectin-3 accumulation at damaged vesicles, hence revealing galectin-3-glycan interactions involved in fibrosis progression and in intracellular galectin-3 activities, is reported. 3,3'-Bis-(4-aryltriazol-1-yl)thiodigalactosides were synthesized and evaluated as antagonists of galectin-1, -2, -3, and -4 N-terminal, -4 C-terminal, -7 and -8 N-terminal, -9 N-terminal, and -9 C-terminal domains. Compounds displaying low-nanomolar affinities for galectins-1 and -3 were identified in a competitive fluorescence anisotropy assay. X-ray structural analysis of selected compounds in complex with galectin-3, together with galectin-3 mutant binding experiments, revealed that both the aryltriazolyl moieties and fluoro substituents on the compounds are involved in key interactions responsible for exceptional affinities towards galectin-3. The most potent galectin-3 antagonist was demonstrated to act in an assay monitoring galectin-3 accumulation upon amitriptyline-induced vesicle damage, visualizing a biochemically/medically relevant intracellular lectin-carbohydrate binding event and that it can be blocked by a small molecule. The same antagonist administered intratracheally attenuated bleomycin-induced pulmonary fibrosis in a mouse model with a dose/response profile comparing favorably with that of oral administration of the marketed antifibrotic compound pirfenidone.
Organizational Affiliation: 
Centre for Analysis and Synthesis, Department of Chemistry, Lund University, P. O. Box 124, 221 00, Lund, Sweden.