Effect of Metal Cations on Non-Enzymatic Glycation in Human Serum Albumin

摘要

In the glucose-only control experiment, an average of 13.7 glucose was added to HSA. Different metal cations had different effects. The number of glucose bind with HSA was slightly reduced in the presence of metal cations during glycation. Cu~(2+) strongly affected the level of glycation; Mg~(2+) also influenced glycation, whereas Fe~(2+) and Zn~(2+) showed little effect. Moreover, higher metal concentration caused a further decrease in glycation, especially in the case of Cu~(2+). This suggests that binding between metal cations and HSA can lock the structure, thus reducing the proteins exposure to glycation. The MALDI-TOF spectra have relatively low mass resolution. High-resolution experiments are required for a more detailed identification of the extent of glycation. In later experiments, the HSA proteins will be enzymatically digested. The structures of these peptides will then be interrogated in detail using the custom-built ESI-quadrupole mass filter-ion trap-TOF instrument, which is particularly suited for laser dissociation experiments.