Sonodynamic Therapy Attenuates TLR4/NF-κB Signaling in Epicardial Adipose Tissue of Atrial Fibrillation: Insights From Animal Models, scRNA-seq, and Mendelian Randomization

Abstract

Atrial fibrillation (AF) is the most common arrhythmia leading to cardioembolic stroke, with inflammation of epicardial adipose tissue (EAT) contributing to its pathogenesis. However, current therapies cannot specifically target EAT inflammation to alleviate AF. This study investigated the effects of sonodynamic therapy (SDT) on reducing macrophage-mediated inflammation in the EAT of rabbit AF models and explored its potential clinical application in AF patients. Rabbits were assigned to sham, paced (600 beats per minute for 4 weeks), and SDT groups. Macrophage infiltration and collagen deposition were evaluated using rat anti-rabbit macrophage antibody 11 immunohistochemistry and Masson staining, respectively. Transcriptomic analysis and network pharmacology identified toll-like receptor 4/nuclear factor-κB pathway genes (including CXCL8 and CCL2 ) as SDT targets for AF treatment, which were validated by Western blot and quantitative real-time polymerase chain reaction. Single-cell sequencing of human EAT and right atrial appendage confirmed the expression of these SDT-targeted genes in macrophages from patients with AF. Mendelian randomization demonstrated that elevated plasma CXCL8, but not CCL2, was associated with an increased risk of AF. SDT reduced macrophage infiltration, fibrosis, and toll-like receptor 4/nuclear factor-κB-mediated inflammation, supporting its therapeutic potential in AF by modulation of EAT inflammation.

Keywords: Mendelian randomization; atrial fibrillation; epicardial adipose tissue; inflammation; sonodynamic therapy.