Galectin-3 and its inhibitors: Overview and perspectives

Galectin-3, a β-galactoside-binding lectin, is a driver and regulator of inflammation and fibrosis, and its levels are elevated in some heart and lung diseases. It also serves as a biomarker for the risk and severity of some forms of heart failure and, potentially, for various other pathological conditions. These observations make galectin-3 a promising potential therapeutic target. Both genetic and pharmacological inhibition of galectin-3 have been shown to ameliorate renal dysfunction and exert protective effects against liver fibrosis in animal models. Several galectin-3 inhibitors have been developed for therapeutic application in various pathological conditions. This review examines the progress of the development of 161 galectin-3 inhibitors, including monosaccharides, oligosaccharides, natural polysaccharides and their derivatives, carbohydrate polymers, antibody-drug conjugates, and non-carbohydrate compounds. Structure-activity relationships are emerging for these inhibitors, and the atypical binding pockets of galectin-3 have informed the development of a pharmacophore model that is expected to guide the design and discovery of potent, selective inhibitors for treatment of cancer, inflammation, and fibrosis.