Table 1.
Epigenetic modifications in inflammatory cells in AAAs.
| Epigenetic Modification | Cellular Origin | Regulation | Target Gene(s) | Related Function |
|---|---|---|---|---|
| DNA Methylation | ||||
| DNMT1, DNMT3A | T-lymphocyte | Downregulated | --- | Potential role in T-cell dysfunction, particularly decreased suppressive effects of CD4 + CD25+ T regulatory cells |
| Histone Modification | ||||
| JMJD3 | Macrophage | Upregulated | H3K27me3 on promoters for: IL1β, TNF, IL23 | Increases macrophage inflammatory cytokine production; macrophage proinflammatory polarization |
| HDAC I and IIa | Macrophage | Upregulated | --- | Increased proinflammatory macrophage phenotype and inflammatory mediators |
| Non-coding RNA | ||||
| miRNA-24 | Macrophage | Upregulated | Chi311 | Limits inflammation and ECM degeneration; overexpression reduces AAA |
| miRNA-33 | Macrophage | Downregulated | ABCA1 | Monocyte chemotaxis, macrophage accumulation; inhibition reduces AAA |
| miRNA-181b | Macrophage | Upregulated | TIMP3, ELN | Downregulates ECM |
| miRNA-223 | Macrophage | Upregulated in tissue, downregulated plasma | MMP12 | Inhibits vascular inflammation |
| miRNA-155 | T-lymphocyte | Upregulated | CTLA4 | Regulation of T-cell activation |
AAA, abdominal aortic aneurysm; ECM, extracellular matrix; IL1β, interleukin 1β; IL23, interleukin 23; TNF, tumor necrosis factor.