Cerium Interferes Iron Binding to Human Serum Apo-Transferrin Which can Affect Iron Metabolism

Iron (Fe) is one of the most abundant metallic elements on the earth and is vital for human health. Some trace elements such as cerium may interfere with iron metabolism. In the present study, the effect of cerium (Ce) interference on intestinal absorption of iron in the first stage of iron metabolism was studied. The spectrophotometry and equilibrium dialysis were used to investigate the interaction of iron and cerium. The interaction of cerium with iron metabolism by interaction with apo-transferrin was investigated. The maximum absorption wavelength of iron-transferrin and cerium-transferrin were obtained 240 nm and 465 nm, respectively. The results showed that cerium was able to bind to apo-transferrin, which binds to transferrin like saturated iron. By obtaining the iron and cerium binding constants in equilibrium dialysis (6.66 × 10⁶ M^-1 and 3.51 × 10⁶ M^-1, respectively), it was determined that the site of interaction of these two ions on apo-transferrin is probably the same and cerium reduces the binding of iron to apotransferrin by 14%. Based on the results obtained in this project, it was found that cerium interferes with iron metabolism so that it can be altered through impaired intestinal absorption, plasma transport, and biochemical processes required for iron. As serum iron levels in humans are tightly regulated, the interference of cerium with iron metabolism may affect human blood functions.