Systemic application of 3-methyladenine markedly inhibited atherosclerotic lesion in ApoE-/- mice by modulating autophagy, foam cell formation and immune-negative molecules

作者:Dai, Shen; Wang, Bo; Li, Wen; Wang, Liyang; Song, Xingguo; Guo, Chun; Li, Yulan; Liu, Fengming; Zhu, Faliang; Wang, Qun; Wang, Xiaoyan; Shi, Yongyu; Wang, Jianing; Zhao, Wei; Zhang, Lining*
来源:Cell Death & Disease, 2016, 7(12): e2498.
DOI:10.1038/cddis.2016.376

摘要

A growing body of evidence demonstrates that autophagy, an evolutionarily conserved intracellular degradation process, is involved in the pathogenesis of atherosclerosis and has become a potential therapeutic target. Here we tested the effect of two inhibitors of phosphatidylinositol 3-kinase, 3-methyladenine (3-MA) and 2-(4-morpholinyl)-8-phenyl-chromone (LY294002), commonly used as inhibitors of autophagy, in atherosclerosis in apolipoprotein E-/- mice. Systemic application of 3-MA but not LY294002 markedly reduced the size of atherosclerotic plaque and increased the stability of lesions in high-fat diet-fed mice as compared with controls. Furthermore, 3-MA had multiple atheroprotective effects, including modulating macrophage autophagy and foam cell formation and altering the immune microenvironment. Long-term treatment with 3-MA promoted oxidized low-density lipoprotein (oxLDL)-induced macrophage autophagy and suppressed foam cell formation and cell viability in vitro. Furthermore, systemic application of 3-MA promoted lipid droplet breakdown and decreased apoptosis, most likely associated with autophagy. 3-MA treatment strikingly enhanced the expression of immune-negative molecules such as interleukin 10 (IL-10), transforming growth factor beta and IL-35, as well as forkhead box P3 (Foxp3), the specific transcriptional factor for regulatory T cells, but did not affect the level of proinflammatory cytokines in the arterial wall. We provide strong evidence for the potential therapeutic benefit of 3-MA in inhibiting atherosclerosis development and improving plaque stability.