Melatonin inhibits liver ferroptosis in copper-laden rats: a potential therapy mechanism underlying Wilson’s disease

Wilson's disease (WD) is an autosomal recessive disorder associated with impaired copper metabolism that results in hepatic manifestations. However, as a rare disease, the underlying pathogenic mechanism and drug development have lagged behind. Studies have reported that copper accumulation is associated with potential increases in iron levels, which can lead to further exacerbation of oxidative damage and has been observed in WD patients. Therefore, removing excess copper from the body and enhancing antioxidant capacity are crucial in treatment. Melatonin (MLT) is an endogenous hormone with anti-oxidative stress, anti-inflammatory, and anti-ferroptosis properties, and can chelate transition metals. Thus, the study aimed to investigated the relationship between WD and ferroptosis, and the therapeutic efficacy and mechanism of MLT using copper-laden rats and HepG2 cell models. Our results suggested that copper overload significantly increased oxidative stress and altering ferroptosis-related metabolites of the liver in copper-laden rats. <i>In vivo</i> and <i>in vitro</i> experiments showed that copper overload disrupts the ceruloplasmin-ferroportin (Cp-Fpn) iron transport system, leading to increased iron levels and promoting ferroptosis, as indicated by the decreased levels of ferroptosis-related proteins GPX4, with these findings further supported by RSL3 and Ferrostatin-1. Further, we found that MLT could improve liver function, iron levels and enhance its antioxidant capacity. In addition, MLT was also able to inhibit ferroptosis by activating the Nrf2/SLC7A11/GPX4 pathway. The effect is more effective than penicillamine, the current therapeutic drugs.Key Policy HighlightsCopper overload induces hepatic ferroptosis in Wilson's disease via iron accumulation, glutathione depletion, and lipid peroxidation.Reduced ceruloplasmin disrupts the ferroportin-mediated iron efflux system, aggravating ferroptosis.Melatonin alleviates liver injury and copper accumulation by inhibiting ferroptosis via activation of the Nrf2/SCL7A11/Gpx4 pathway.