Sweetener aspartame aggravates atherosclerosis through insulin-triggered inflammation

Abstract

Consumption of artificial sweeteners (ASWs) in various foods and beverages has been linked to an increased risk of cardiovascular diseases (CVDs). However, molecular mechanisms underlying ASW-associated CVD remain unknown. Here, we show that consumption of 0.15% aspartame (APM) markedly increased insulin secretion in mice and monkeys. Bilateral subdiaphragmatic vagotomy (SDV) obliterated APM-elevated blood insulin levels, demonstrating crucial roles of parasympathetic activation in regulation of insulin secretion. Incessant APM feeding of ApoE^-/^- mice aggravated atherosclerotic plaque formation and growth via an insulin-dependent mechanism. Implantation of an insulin-slow-release pump in ApoE^-/- mice exacerbated atherosclerosis. Whole-genome expression profiling discovered that CX3CL1 chemokine was the most upregulated gene in the insulin-stimulated arterial endothelial cells. Specific deletion of a CX3CL1 receptor, Cx3cr1 gene, in monocytes/macrophages completely abrogated the APM-exacerbated atherosclerosis. Our findings uncover a novel mechanism of APM-associated atherosclerosis and therapeutic targeting of the endothelial CX3CL1-macrophage CX3CR1 signaling axis provides an approach for treating atherosclerotic CVD.