Copper ions and copper-protein complexes (Cu)

Copper is a vital trace element that serves as a mandatory cofactor for numerous enzymes involved in critical physiological processes, including cellular respiration (cytochrome c oxidase), antioxidant defense (superoxide dismutase), and iron metabolism (ceruloplasmin) [1][2]. Under normal conditions, copper is tightly regulated; however, free or labile copper ions can become pathologically elevated, leading to oxidative stress via Fenton-like chemistry and the formation of toxic protein aggregates [3][4]. In Wilson disease, genetic mutations lead to the accumulation of copper in the liver and brain, while in oncology, copper is recognized as a limiting factor for angiogenesis and tumor growth [5][6]. Therapeutic intervention typically involves the use of chelating agents, such as penicillamine or trientine, which bind to free copper ions to facilitate their excretion, or tetrathiomolybdate, which forms stable complexes with copper and proteins to reduce bioavailability [7][8]. Managing copper levels is also a strategy in neurodegenerative research, where ionophores are investigated to redistribute copper from extracellular plaques back into neurons [9]. Sources: [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3226306/ [2] https://uniprot.org/locations/SL-0074 [3] https://pubmed.ncbi.nlm.nih.gov/12606104/ [4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4311551/ [5] https://www.niddk.nih.gov/health-information/liver-disease/wilson-disease [6] https://pubmed.ncbi.nlm.nih.gov/15591233/ [7] https://pubchem.ncbi.nlm.nih.gov/compound/Penicillamine [8] https://pubmed.ncbi.nlm.nih.gov/10959118/ [9] https://pubmed.ncbi.nlm.nih.gov/24103475/

Other names

Labile copperExchangeable copperNon-ceruloplasmin bound copperCuCopper(II)Copper(I)Cuproproteins

Chelation of free copper ions to promote urinary excretion, sequestration of copper into stable complexes to prevent bioavailability, and competitive inhibition of intestinal copper absorption.