Since macrophage infiltration is a key process in the development of AAA, the effect of miR-33-5p downregulation was investigated in human THP-1 macrophages, which revealed that this markedly increased ABCA1 expression and reduced the expression levels of proinflammatory markers such as TNFα, metalloproteinase (MMP)-2, and MMP-9 via the PI3K/AKT signalling pathway [110]. This evidence concerns the gene ABCA1 and triple-A syndrome.