Does low-density lipoprotein cholesterol induce inflammation? If so, does it matter? Current insights and future perspectives for novel therapies.

Abstract

Dyslipidemia and inflammation are closely interrelated contributors in the pathogenesis of atherosclerosis. Disorders of lipid metabolism initiate an inflammatory and immune-mediated response in atherosclerosis, while low-density lipoprotein cholesterol (LDL-C) lowering has possible pleiotropic anti-inflammatory effects that extend beyond lipid lowering. Activation of the immune system/inflammasome destabilizes the plaque, which makes it vulnerable to rupture, resulting in major adverse cardiac events (MACE). The activated immune system potentially accelerates atherosclerosis, and atherosclerosis activates the immune system, creating a vicious circle. LDL-C enhances inflammation, which can be measured through multiple parameters like high-sensitivity C-reactive protein (hsCRP). However, multiple studies have shown that CRP is a marker of residual risk and not, itself, a causal factor. Recently, anti-inflammatory therapy has been shown to decelerate atherosclerosis, resulting in fewer MACE. Nevertheless, an important side effect of anti-inflammatory therapy is the potential for increased infection risk, stressing the importance of only targeting patients with high residual inflammatory risk. Multiple (auto-)inflammatory diseases are potentially related to/influenced by LDL-C through inflammasome activation. Research suggests that LDL-C induces inflammation; inflammation is of proven importance in atherosclerotic disease progression; anti-inflammatory therapies yield promise in lowering (cardiovascular) disease risk, especially in selected patients with high (remaining) inflammatory risk; and intriguing new anti-inflammatory developments, for example, in nucleotide-binding leucine-rich repeat-containing pyrine receptor inflammasome targeting, are currently underway, including novel pathway interventions such as immune cell targeting and epigenetic interference. Long-term safety should be carefully monitored for these new strategies and cost-effectiveness carefully evaluated.