Experimental evidence on colchicine's mode of action in human carotid artery plaques

Abstract Background and aims Atherosclerosis driven by inflammation is a major cause of cardiovascular events. Recent clinical trials have demonstrated the therapeutic potential of anti-inflammatory treatments. Consequently, colchicine is recommended in current guidelines as a second-line therapy for secondary prevention, although the drug's mechanism of action is not fully understood. Methods To this end, we performed a multiomic study of the effect of colchicine on human carotid plaques. Sections from endarterectomy specimens were exposed ex vivo to colchicine at concentrations of 2 ng/ml and 10 ng/ml for 24 hours and compared with untreated segments of the same plaque. Changes in gene expression were analyzed by RNA sequencing, and plaque secretomes were subjected to proteomic analysis by mass spectrometry. In situ cell proliferation was examined histologically. Results Our data suggest that colchicine primarily suppresses neutrophil and platelet degranulation, collagen degradation, and macrophage proliferation in atheromatous plaques in a dose-dependent manner, while stimulating myofibroblast activation. Conclusion Our study demonstrates multifactorial pathways by which colchicine, the first anti-inflammatory drug recommended by cardiovascular guidelines, acts on human atherosclerotic lesions. Targeting neutrophil and platelet degranulation, collagen degradation and macrophage proliferation could provide significant therapeutic benefit in atherosclerotic cardiovascular disease without the adverse side effects of colchicine.