Salvianolic acid B attenuates abdominal aortic aneurysm via inhibition of ferroptosis and inflammation.

Abstract

BACKGROUND: Abdominal aortic aneurysm (AAA) is a life-threatening vascular disorder characterized by progressive aortic wall degeneration, inflammation, and vascular smooth muscle cells (VSMCs) loss. Despite extensive research, no effective pharmacological treatment is currently available to prevent or halt AAA progression. PURPOSE: This study aimed to discover effective therapeutic agents for AAA and identify potential natural compounds with pharmacological efficacy against the disease by targeting matrix metalloproteinase-2 (MMP2), a key enzyme involved in extracellular matrix degradation and aneurysm progression. METHODS: An integrated screening strategy combining cytotoxicity evaluation, high-content immunofluorescence imaging, and molecular docking was applied to an angiotensin II (Ang II)-stimulated rat aortic smooth muscle cells (RASMCs) model. A total of 138 natural products were systematically assessed. The anti-aneurysmal efficacy of the identified compound was further validated in both CaCl₂-induced and Ang II-infused ApoEmouse models of AAA. Network pharmacology and metabolomic analyses were performed to elucidate the underlying molecular mechanisms. RESULTS: Salvianolic acid B (Sal B), a major polyphenol from Salvia miltiorrhiza, was identified as a potent anti‑AAA candidate. It suppressed aneurysm formation, reduced elastin degradation, and attenuated inflammatory infiltration in vivo, while preserving the contractile phenotype, lowering ROS, and inhibiting MMP activity in Ang II‑stimulated RASMCs in vitro. Mechanistically, Ang II suppresses NRF2, leading to downregulation of the System Xc⁻-GPX4 axis and promoting lipid peroxidation and VSMC ferroptosis. This ferroptosis then activates the AGE-RAGE pathway, amplifying inflammation and MMP‑driven matrix degradation. Sal B counteracts this cascade by restoring NRF2 activity, improving lipid metabolism, and inhibiting MMPs, thereby blocking ferroptosis‑initiated inflammation and preserving aortic integrity. CONCLUSION: Salvianolic acid B exerts protective effects against AAA by attenuating oxidative stress, ferroptosis, and inflammation. These findings highlight Sal B as a promising natural therapeutic candidate for the prevention and treatment of abdominal aortic aneurysm.