High copper levels induce oxidative stress and inflammatory processes in a cell culture model of Wilson’s disease

Wilson’s disease (WD) is a genetic disorder resulting from mutations in the ATP7B gene that lead to copper overload in hepatocytes. To gain a deeper understanding of the cellular mechanisms underlying WD, a reanalysis of the GSE1073236 dataset was conducted and validated by comparative analyses in a cell culture model of HepG2 and HepG2 ATP7B knockout (ATP7B-KO) cells, as well as in primary hepatocytes from WD patients and controls. Increased expression levels of genes associated with autophagy, oxidative stress and inflammation were observed in copper-treated HepG2 ATP7B-KO cells and in primary hepatocytes from patients with WD. Furthermore, copper increased the secretion of IL1B, TNF, GM-CSF, and IL8 in HepG2 ATP7B-KO cells. Accordingly, copper exposure enhanced NFKB promoter activity 6 h after treatment. However, the transcriptional activity of AP1 and NFKB was reduced in these cells 24 h after treatment with 0.6mM CuCl 2 . In addition, both HepG2 and HepG2 ATP7B-KO cells showed increased oxidative stress and H 2 O 2 levels after copper treatment, indicating that reactive oxygen species could play a role in WD. In the WD cell culture model, critical mechanisms behind copper-related cell death highlight the importance of this model in developing molecular targets for future therapeutic strategies. A Copper is transported through APT7B in the Golgi apparatus where it is loaded onto ceruloplasmin for secretion. In case of excess copper, it is released into bilary canaliculi by ATP7B via lysosomes and exocytosis. B In Wilson disease various mutations in the ATP7B gene lead to a loss of function of the protein causing a copper build-up that triggers autophagy, oxidative stress, and inflammation, driven in part by altered NFKB and AP1 signalling. This study highlights how copper overload promotes cellular damage and inflammatory responses, deepening the understanding of the molecular mechanisms underlying Wilson's disease