Semaglutide attenuates diabetic vascular calcification by enhancing autophagy and lysosomal function via targeting CPNE1
S Xiao, Y LiuAbstract
Background
Diabetic patients are highly susceptible to vascular calcification, a pathological process lacking specific therapies. Semaglutide, a Glucagon-like peptide-1 receptor agonist (GLP-1RA), provides cardiovascular protection, but its direct effect on diabetic vascular calcification (DVC) and the underlying mechanisms remain unclear.
Purpose
This study aims to investigate whether Semaglutide attenuates DVC by modulating autophagy and lysosomal function in vascular smooth muscle cells (VSMCs) and to explore the potential involvement of CPNE1 in this process.
Methods
In vivo, DVC was induced in db/db mice using Vitamin D3, followed by treatment with Semaglutide (5 or 10 nmol/kg/day) for 14 days. Aortic calcification was assessed via Von Kossa staining, calcium content, and expression of osteogenic markers (RUNX2, BMP2). In vitro, MOVAS cells were stimulated with AGEs-BSA to model DVC. Autophagic flux and lysosomal function were evaluated using mRFP-GFP-LC3 adenovirus transfection, immunofluorescence, LysoTracker Red, and Western blotting for autophagy-related proteins (LC3-II, P62, LAMP1/2, CTSD/B). Transcriptome sequencing was performed to identify potential targets of Semaglutide, followed by CPNE1 overexpression experiments to validate its role.
Results
Semaglutide dose-dependently reduced aortic calcium deposition and downregulated RUNX2 and BMP2 expression in diabetic mice. In vitro, Semaglutide alleviated AGEs-BSA-induced calcification in MOVAS. Mechanistically, AGEs-BSA impaired autophagic flux and lysosomal function, as evidenced by accumulated autophagosomes, elevated P62 and LC3-II, reduced lysosomal proteins, and diminished lysosomal acidity and degradative capacity. Semaglutide treatment reversed these abnormalities, restoring autophagic flux and lysosomal function. Transcriptome analysis identified CPNE1 as a significantly downregulated gene following Semaglutide treatment. Notably, overexpression of CPNE1 abolished the protective effects of Semaglutide, reversing the restoration of autophagic flux and the inhibition of osteogenic differentiation.
Conclusions
Semaglutide attenuates diabetic vascular calcification by downregulating CPNE1, thereby restoring impaired autophagic flux and lysosomal function in VSMCs. These findings reveal a novel CPNE1-dependent mechanism and position the Semaglutide-CPNE1-autophagy axis as a promising therapeutic strategy for DVC.Picture file 1Picture file 2