Spinal cord ischemia reperfusion injury induces cuproptosis in neurons

Spinal cord ischemia reperfusion injury (SCIRI) is a serious disease that can result in irreversible neuronal damage, leading to the loss of sensory and motor function. Cuproptosis, a novel form of regulated cell death, has been studied in various diseases. However, the role and mechanism of cuproptosis in SCIRI remain to be elucidated. The results of transcriptome analysis showed significant downregulation of ATP7B, which regulates copper ion efflux. Concurrently, another key cuproptosis-related gene, FDX1, was significantly altered. Thus, we performed qPCR and Western blot assays in vivo and in vitro to detect changes in cuproptosis-related genes. The results indicated that cuproptosis was indeed activated by SCIRI or OGD/R. Moreover, immunofluorescence/immunohistochemitry staining and neuronal activity tests were consistent with the above results. Furthermore, we also proved that ammonium tetrathiomolybdate, a copper chelator and cuproptosis inhibitor, could not only ameliorate neuronal damage and promote neuronal survival but also improve lower limb motor dysfunction. SCIRI caused ATP7B downregulation, which blocked copper ion efflux, leading to copper ion accumulation, DLAT oligomerization, degradation of iron-sulfur cluster proteins and ultimately cuproptosis in neurons.