Copper(II) ion (Cu2+) (Cu2+)

Copper(II) ions (Cu2+) within the free or exchangeable copper pool represent the fraction of systemic copper that is not tightly bound to ceruloplasmin, making it chemically reactive and biologically available (Gromadzka et al., 2014). This pool is essential for the function of vital enzymes such as cytochrome c oxidase and superoxide dismutase, yet it must be strictly regulated to prevent oxidative damage via Fenton-like chemistry (StatPearls, 2023). In Wilson disease, mutations in the ATP7B transporter lead to an expansion of this labile pool, causing toxic accumulation in the liver and brain (NIH, 2023). Conversely, in oncology, this pool is targeted by ionophores like elesclomol to trigger cuproptosis, a form of regulated cell death characterized by the aggregation of lipoylated mitochondrial proteins (Tsvetkov et al., 2022). Therapeutic strategies focus on either sequestering excess Cu2+ using chelators like penicillamine to promote excretion or redistributing it to induce selective cytotoxicity in malignant cells (PubChem, 2024).

Other names

Labile copper poolExchangeable copperFree copperNon-ceruloplasmin bound copperCupric ionExchangeable copper pool

Chelation of excess copper to facilitate urinary excretion; ionophore-mediated intracellular copper delivery to induce cuproptosis; inhibition of intestinal copper absorption via induction of metallothionein.