Distribution of protein-bound zinc in normal and cirrhotic serum

Clinical Significance of Evaluation of Serum Zinc Concentrations in C-Viral Chronic Liver Disease

“…Several hypotheses have been put forward to explain why the serum concentration of zinc decreases with development of liver disease: First, zinc exists in the blood, where one-third of it is bound to α 2 -macroglobulin and the rest is bound to albumin. The serum concentration of zinc consequently decreases with decreases in the albumin concentration as the liver disease develops [18,19]. Second, when a shunt between the portal vein and the systemic circulation is enlarged with development of disease, the amount of zinc excreted into the urine increases, and as a result, the serum zinc concentration decreases [20].…”

An in vitro study of interactions between insulin-mimetic zinc(II) complexes and selected plasma components

“…The complex formation equilibria (stoichiometry and stability constants) for the parent systems are known in the literature under our selected experimental conditions in almost all cases [17,22,23]. However, serum proteins can also bind considerable amounts of zinc(II) or its complexes [24,25]. The hypothesis is widely held that circulating zinc is transported mainly by albumin, and that transferrin is the carrier of newly absorbed zinc in the portal plasma [24].…”

Biodistribution of anti‐diabetic Zn(II) complexes in human serum and in vitro protein‐binding studies by means of CZE–ICP‐MS

“…The binding site is situated at the interface of domains I and II, which consists of two Hisnitrogen atoms (His-67, His-247), two carboxylate-oxygen donor atoms (Asn-99, Asp-249) and a water molecule in the coordination sphere, and the Zn center adopts a distorted trigonal bipyramidal geometry [26,34]. a2M is a fairly large protein with 720 kDa, but found at much lower concentration in the blood than albumin (2-6 mM), and with conditional formation constants of logK 1 ' 5 7.49 and logK 2 ' 5 5.12 it has also considerable Zn(II)-binding properties [29,[35][36][37]. Another possible Zn(II) binder is the 79 kDa iron transport protein Tf (37 mM in serum), but 30% of the binding sites are occupied by Fe(III) ions in the serum [27,33].…”

“…Literature data show that most of the total serum Zn(II) is bound to the serum proteins (appr. 98%) and HSA is the primary target (80-90%) [32,35,37], followed by a2M (5-15%) [35][36][37]. However, the role of Tf is under discussion [36,38] and also a minority of Zn(II) is circulating unbound or attached to LMM components (considered as the mobile portion of the metal ion).…”