Copper-quercetin complexes: methods of study, relevance to cell death pathways, therapeutic applications.

Copper-quercetin complexes, CuQ, have been an active area of research for several decades. In vitro experiments show complexes are better antioxidants than quercetin alone. There seems to be a synergy effect. Cancer cell culture experiments also show prooxidant and DNA damaging properties which may be exploitable in cancer cell therapy. The effect of copper in combination with quercetin on cell death pathways needs to be investigated, especially regarding the cuproptosis pathway. CuQ complexes may require formulations similar to quercetin. The use of nanoparticles has enabled practical formulations of quercetin and/or their complexes to be made which guarantee stability, satisfactory bioavailability, and clinical effectiveness. In vivo studies are also being reported as well of planning of applications including skin infections and bone healing. Zn, Cu and quercetin tested on mice shows strong potential to treat Androgenic Alopecia. Copper-quercetin complexes seem to be easy to make and have good pharmacological potential in antimicrobial function, osteogenesis, angiogenesis and cancer treatment. Complexes such as those involving phenoanthroline, quercetin and copper may be found to be superior and zinc might be better for cancer therapy.