Regulatory impact of statins on macrophage polarization: mechanistic and therapeutic implications

Statins, also known as HMG-CoA reductase inhibitors, are widely prescribed drugs for the prevention and treatment of cardiovascular diseases. In addition to their lipid-lowering effects, these compounds have been found to possess immune-modulating properties. Macrophages, which are crucial phagocytic cells in the body, can be divided into two main subsets: M1 (proinflammatory) and M2 (anti-inflammatory). While there is evidence suggesting that statins exert an anti-inflammatory action on macrophages and promote their polarization towards the M2 subset, recent studies have identified the proinflammatory impact of statins on macrophages, leading to polarization towards the M1 subset. For example, statins have been shown to inhibit NF-κB activation to promote anti-inflammatory responses. On the other hand, statins can induce NFκB/AP-1 activation and increase IL-1β secretion in macrophages to promote pro-inflammatory responses. This review aims to provide a comprehensive overview of both in vivo and in vitro studies that have investigated the effects of statins on macrophage polarization and inflammatory responses in various diseases. Furthermore, this review seeks to evaluate the underlying mechanisms involved in these effects. By summarizing the existing evidence, this review contributes to our understanding of the complex interactions between statins and macrophages in different disease contexts.