Adiponectin improves the aortic dissection by inhibiting inflammatory cell infiltration and macrophage pyroptosis

OBJECTIVE: Aortic dissection (AD) is a fatal cardiovascular emergency that is predominantly induced by long-term uncontrolled hypertension. MATERIALS AND METHODS: The mouse AD model was established by combining β-aminopropionitrile with angiotensin II. The incidence rate, rupture rate, and survival status of the mice were evaluated. The structural damage of the aorta was observed using tissue staining technology, the extracellular matrix status, and macrophage pyroptosis were evaluated by immunofluorescence staining, the infiltration of inflammatory cells was detected by immunohistochemistry, the expression of pyroptosis-related molecules, and inflammatory factors was analyzed by Western blotting and enzyme-linked immunosorbent assay (ELISA). Cell proliferation was detected by EdU staining, and cell apoptosis was detected by flow cytometry. RESULTS: In the aortic tissues of AD model mice, the expression of APN, and the content of APN in the serum were significantly decreased. APN intervention can alleviate the thickening of the aortic media, rupture of elastic fibers, and degradation of the extracellular matrix. APN inhibits the proliferation, apoptosis, and phenotypic transformation of vascular smooth muscle cells (VSMCs). At the same time, it can inhibit the infiltration of neutrophils and macrophages and the inflammatory response. Underlying mechanism, it was found that APN inhibited NLRP3-mediated pyroptosis by reducing the release of inflammatory factors; this effect was dependent on the phosphorylation activation of AMPKα and APN receptor. CONCLUSION: APN plays a protective role in AD. Its underlying mechanism is related to the activation of the AMPK pathway, which in turn inhibits macrophage pyroptosis and vascular inflammation. This study offers a new perspective for the pathological mechanism of AD.