Apolipoprotein AI as Therapy for Atherosclerosis: Does the Future of Preventive Cardiology Include Weekly Injections of the HDL Protein?

Abstract

Conventional wisdom suggests that halting or reversing long-term atherosclerosis requires increasing the amount of circulating high-density lipoprotein (HDL) coursing through the vasculature. However, recent evidence seems to indicate that reducing the size of cholesterol-containing lipid plaques might be accomplished by methods that either do not raise or, in fact, lower the amount of circulating HDL. Carriers of apoAI_Milano, a variant of apoprotein AI (a component of HDL), have reduced levels of circulating low-density lipoprotein (LDL). Intriguingly, these individuals have reduced amounts of circulating HDL and total apoAI. Infusions of the ApoAI_Milano variant given to patients with coronary atherosclerosis appear to lead to disease regression and reduced plaque size. However, larger studies are required to provide definitive proof of apoAI_Milano’s benefits. What is certain is that attention should be focused on the removal of cholesterol from plaques rather than simply desiring to raise HDL concentrations in patients.