Advanced Glycation End Products Induce Cuproptosis and Then Promote the Activation and Migration of Cardiac Fibroblasts

Abstract

Excessive advanced glycation end products (AGEs) can lead to cardiovascular diseases such as myocardial fibrosis (MF). Although studies have found that AGEs induce cuproptosis, and cuproptosis promotes fibrosis, it has not been confirmed whether AGEs promote MF through cuproptosis. AGEs increased intracellular copper levels, promoted the expression of solute carrier family 31 member 1 (SLC31A1), and downregulated the expression of ferredoxin 1 (FDX1), lipoic acid synthetase (LIAS), lipoylated (Lip)-dihydrolipoamide S-succinyltransferase (DLST), and Lip-dihydrolipoamide S-acetyltransferase (DLAT) in cardiac fibroblasts (CFs). All of these key cuproptosis regulatory gene expression abnormalities indicate that cuproptosis is induced. AGEs also decreased adenosine triphosphate content and inhibited the activities of mitochondrial complexes I and III, but these regulatory effects were significantly weakened after SLC31A1 downregulation. Meanwhile, AGEs significantly promoted the expression of alpha smooth muscle actin, collagen I, collagen III, and transforming growth factor-β1, while SLC31A1 siRNA or copper chelator ammonium tetrathiomolybdate (TTM) blocked these promoting effects. Similarly, CuCl₂ also induced fibrosis gene expression, while SLC31A1 overexpression (SLC31A1-O) further enhanced these effects, but TTM reduced CF activation induced by CuCl₂ plus SLC31A1-O. In addition, AGEs significantly promoted cell migration and enhanced the expression and secretion of matrix metalloproteinase (MMP)-2 and MMP-9, while SLC31A1 siRNA or TTM weakened these effects. SLC31A1-O plus copper treatment also had similar effects to AGEs, and these effects could also be blocked by TTM. Therefore, AGEs enhance copper transport by promoting SLC31A1 expression, which leads to intracellular copper overload and then induces cuproptosis, and finally promotes CF activation and migration.