The local effects of proprotein convertase subtilisin/kexin type 9 (PCSK9) on the inflammatory atheroma: beyond LDL cholesterol lowering

Proprotein convertase subtilisin/kexin type 9 (PCSK9) has gained extensive attention since the discovery of its role in mediating hepatic low-density lipoprotein (LDL)-receptor (LDLR) degradation, and therefore regulating plasma LDL cholesterol clearance. However, emerging studies have indicated that PCSK9 may have pleiotropic effects on the development of atherosclerosis and eventually cardiac dysfunction by mechanisms independent of the regulation of LDL cholesterol levels. In this review, we will discuss recent findings of how PCSK9 affects cellular responses and the pro-inflammatory microenvironment within the local atherosclerotic vascular wall, which are critical for atherosclerotic plaque progression. We will also discuss recent research on the potential direct effects of PCSK9 on cardiomyocyte viability and function. These pathways may be critical for understanding the mechanisms of PCSK9’s cardioprotective effects beyond LDL cholesterol lowering