Chungang Zhai

Background/Objectives: Regadenoson, a selective adenosine A_2A receptor agonist, is primarily prescribed for myocardial perfusion imaging (MPI). As its clinical use becomes more widespread in practice, assessing its safety in real-world settings is essential. Methods: In this research, disproportionality analysis was applied to evaluate the safety of Regadenoson by examining all adverse event (AE) reports since 2004 in the FDA Adverse Event Reporting System (FAERS), in which Regadenoson was identified as the primary suspected drug. The reporting odds ratio (ROR), proportional reporting ratio (PRR), multi-item gamma Poisson shrinker (MGPS), and Bayesian confidence propagation neural network (BCPNN) were used to analyze AEs associated with Regadenoson. The Weibull distribution was utilized to model the temporal risk of AEs. Results: The results confirmed some known adverse reactions, such as nausea, shortness of breath (dyspnea), palpitations/vomiting, headache, dizziness, chest pain, and flushing (facial redness or warmth), which were also listed on the drug’s label. New potential adverse reactions not mentioned in the label were identified, including micturition urgency, mental status changes, conversion disorder, eye movement disorder, and genital paraesthesia. This study highlighted the significance of monitoring AEs, particularly right after the start of Regadenoson administration. Conclusions: This study provides preliminary safety data on Regadenoson’s real-world use, corroborating known adverse effects while uncovering new potential risks. These findings offer valuable safety insights for clinicians when prescribing Regadenoson for the use of MPI.

Rationale: The NLRP3 (NLR [NOD-like receptor] family, pyrin domain containing 3) inflammasome is an important driver of atherosclerosis. Our previous study shows that chaperone-mediated autophagy (CMA), one of the main lysosomal degradative process, has a regulatory role in lipid metabolism of macrophages. However, whether the NLRP3 inflammasome is regulated by CMA, and the role of CMA in atherosclerosis remains unclear. Objective: To determine the role of CMA in the regulation of NLRP3 inflammasome and atherosclerosis. Methods and Results: The expression of CMA marker, LAMP-2A (lysosome-associated membrane protein type 2A), was first analyzed in ApoE ^−/− mouse aortas and human coronary atherosclerotic plaques, and a significant downregulation of LAMP-2A in advanced atherosclerosis in both mice and humans was observed. To selectively block CMA, we generated macrophage-specific conditional LAMP-2A knockout mouse strains in C57BL/6 mice and ApoE ^−/− mice. Deletion of macrophage LAMP-2A accelerated atherosclerotic lesion formation in the aortic root and the whole aorta in ApoE ^−/− mice. Mechanistically, LAMP-2A deficiency promoted NLRP3 inflammasome activation and subsequent release of mature IL (interleukin)-1β in macrophages and atherosclerotic plaques. Furthermore, gain-of-function studies verified that restoration of LAMP-2A levels in LAMP-2A–deficient macrophages greatly attenuated NLRP3 inflammasome activation. Importantly, we identified the NLRP3 protein as a CMA substrate and demonstrated that LAMP-2A deficiency did not affect the NLRP3 mRNA levels but hindered degradation of the NLRP3 protein through CMA pathway. Conclusions: CMA function becomes impaired during the progression of atherosclerosis, which increases NLRP3 inflammasome activation and secretion of IL-1β, promoting vascular inflammation and atherosclerosis progression. Our study unveils a new mechanism by which NLRP3 inflammasome is regulated in macrophages and atherosclerosis, thus providing a new insight into the role of autophagy-lysosomal pathway in atherosclerosis. Pharmacological activation of CMA may provide a novel therapeutic strategy for atherosclerosis and other NLRP3 inflammasome/IL-1β–driven diseases.