Apolipoprotein M (ApoM) is a novel apolipoprotein that was discovered in 1999 and is bound primarily to high-density lipoproteins (HDLs) in the plasma. Multiple factors may influence its expression at both the post-transcriptional and the transcriptional levels both in vivo and ex vivo as follows: hepatocyte nuclear factor-1 alpha, 4 alpha (HNF-1 alpha, 4 alpha), liver receptor homolog-1 (LRH-1), forkhead box A2 (Foxa2) and platelet activating factor (PAF) upregulate its expression; liver X receptor (LXR), retinoid X receptor (RXR), famesoid X receptor (FXR), small heterodimer partner (SHP) an...