Effect of Oral Administration of Colchicine on Progression of Aortic Aneurysm in Mice

The pathogenesis of aortic aneurysm (AA) is characterized by chronic inflammation of the aortic wall, the associated accumulation of macrophages, and degradation of the extracellular matrix, including elastin. Colchicine (COL) has long been known for its anti-inflammatory effects, so in this study we investigated its effects on AA. In vitro, tumor necrosis factor (TNF)-α-stimulated macrophages and vascular smooth muscle cells (VSMCs) were treated with and without COL for 24 h. Unstimulated cells were used as controls. COL significantly reduced interleukin (IL)-1β, TNF-α, monocyte chemotactic protein (MCP)-1, nuclear factor kappa B (NF-κB), matrix metalloproteinase (MMP)-9, and activated caspase-1 in macrophages, and increased lysyl oxdase (Lox) and tissue inhibitor of metalloproteinase (TIMP)-2 expression in VSMCs. In vivo, aged male apolipoprotein E-deficient (ApoE-/-) mice were infused with angiotensin II (Ang II) for 28 days. The mice received either normal saline (NS) or COL orally. The control group of ApoE-/-mice did not receive Ang II infusion or treatment. COL significantly suppressed aortic enlargement and reduced AA incidence by preserving elastin and decreasing IL-1β, TNF-α, MCP-1, NLRP3 inflammasome, neutrophil elastase, and myeloperoxidase expression. No significant differences were observed in the enzymatic activities of MMP-2 and MMP-9 between the 2 groups. The results suggested that COL prevents AA progression in a clinically relevant model and is expected to be a novel preventive agent for AA.