Mild low-temperature photothermal therapy demonstrated a distinctive 'hot spring' effect in the multichannel regulation of atherosclerosis instead of inducing foam cell apoptosis

Atherosclerosis (AS), characterized by endothelial injury, progressive inflammation, and lipid deposition, can cause adverse cardiovascular events. However, effectively addressing all these pathological conditions simultaneously is challenging. To devise a comprehensive treatment strategy for AS, we developed a nanoparticlebased mild photothermal therapy (PTT) approach, which controlled the temperature within the range of 42-45 degrees C, creating a unique 'hot spring' effect. The nanoparticles used in this therapy consist of a core made of zeolitic imidazolate framework-8 (ZIF-8) nanoparticles loaded with indocyanine green (IR820), and an outer shell made of L-arginine (LA)-modified polydopamine (PDA), which is further modified with hyaluronic acid (HA) to target plaques. In vitro studies have demonstrated that mild PTT can open the TRPV1 channel in foam cells and regulate lipid metabolic diseases by maintaining a controlled temperature range of 42-45 degrees C. Furthermore, the LA-PDA shell has anti-inflammatory properties, decreasing NLRP3 expression. Moreover, the eNOS/NO pathway was activated by LA, promoting the healing of injured endothelial cells (ECs). Additionally, the increased temperature enhances HSP90 expression, thereby helping to maintain eNOS. In vivo studies further confirmed that the HLPIZ-guided 'hot spring' effect has impressive anti-atherosclerotic capability by scavenging lipids, reducing inflammation, and repairing injured ECs simultaneously. In conclusion, our study confirmed that HLPIZ-guided mild PTT can exhibit a 'hot spring' effect, effectively regulating three key pathophysiological processes of AS, being a novel, potentially effective strategy for anti-AS therapy.