Nano-Windmill Inhibits Macrophage Activation Via Choline Uptake Reduction

This study aims to investigate the anti-inflammatory effects of a novel tetrahedral framework nucleic acid (tFNA)-based siRNA delivery system, named “nano-windmill,” which targets slc44a1 to inhibit macrophage activation by reducing choline uptake. The nano-windmill was synthesized by loading siR-slc44a1 onto tFNA. Its characteristics were analyzed by PAGE, TEM, and DLS. Cellular uptake, enzyme cleavage, and siRNA stability were evaluated. Bone marrow-derived macrophages (BMDMs) and THP-1 cells were used for in vitro experiments, while mouse models of sepsis and periodontitis were used for in vivo validation. Metabolomics, RNA sequencing, qPCR, Western blot, and histological analysis were performed to assess the effects on macrophage activation, cytokine expression, and organ damage. The nano-windmill efficiently delivered and protected siR-slc44a1, significantly reducing slc44a1 expression and choline uptake in macrophages. It inhibited the activation of the NLRP3 inflammasome by promoting mitochondrial depolarization and mitophagy, thereby decreasing ROS production and cytosolic mtDNA release. In vivo, the nano-windmill alleviated sepsis-induced organ damage and reduced alveolar bone loss in a periodontitis model. The nano-windmill effectively inhibits macrophage overactivation and exerts superior anti-inflammatory effects through metabolic reprogramming of macrophages, suggesting a promising strategy for treating inflammatory diseases.