A natural small molecule isoginkgetin alleviates hypercholesterolemia and atherosclerosis by targeting ACLY

Rationale: Atherosclerotic cardiovascular disease (ASCVD) represents the predominant cause of mortality and morbidity globally. Given the established role of hypercholesterolemia as a significant risk factor for ASCVD, the discovery of new lipid-lowering medications is of paramount importance. ATP citrate lyase (ACLY) is a crucial enzyme in cellular metabolism, providing acetyl-CoA as the building block for the biosynthesis of fatty acids and cholesterol. Consequently, it has emerged as a promising drug target for innovative treatments of lipid metabolic disorders. Methods: Virtual screening of a natural product library was performed to identify small-molecule ACLY inhibitors, leading to the discovery of isoginkgetin (ISOGK). The lipid-lowering and anti-atherosclerotic effects of ISOGK were validated in hypercholesterolemic diet-induced animal models (mice and hamsters). The inhibitory effects of ISOGK on ACLY enzymatic activity were measured using commercial assay kits. The direct interaction between ISOGK and ACLY was confirmed by surface plasmon resonance (SPR) and cellular thermal shift assays (CETSA). Liver-specific ACLY knockdown mice were generated using GalNAc-conjugated siRNA (GalNAc-siAcly). Results: ISOGK directly bind to ACLY and inhibit its enzymatic activity in vitro and in vivo. By inhibiting ACLY, ISOGK treatment thus alleviates hypercholesterolemia and atherosclerosis in mice and hamsters. However, ISOGK fails to attenuate lipid accumulation and the expression of lipid-metabolism related genes in Acly knockout or depleted hepatocytes. In vivo, the lipid-lowering and anti-atherosclerotic effects of ISOGK were reversed by hepatic knockdown of Acly via treatment with GalNAc-siAcly in mice. Conclusions: Taken together, the present study identifies ISOGK as an effective and naturally-occurring small-molecule inhibitor of ACLY that limits hypercholesterolemia and atherosclerosis. ISOGK thus serves as a promising drug lead in cardiovascular therapeutics.