Structural Characterization of Zinc-Sucrose Complex and Its Ability to Promote Zinc Absorption in Caco-2 Monolayer Cells and Mice

Sucrose emerges as a metal-ion chelatingagent with excellent stabilitythat may increase metal-ion absorption. This study aimed to characterizethe structure of zinc-sucrose complex and investigate its abilityto promote zinc absorption in Caco-2 monolayer cells and mice. Basedon the results of the inductively coupled plasma emission spectrometer(ICP-ES), scanning electron microscopy-energy-dispersive X-rayspectroscopy (SEM-EDX), and Fourier transform infrared spectroscopy(FT-IR), it can be inferred that zinc and sucrose were chelated ata 1:1 ratio, with the hydroxyl groups playing a significant role.The Caco-2 monolayer cell model revealed that zinc-sucrosecomplex increased the amount of zinc uptake, retention, and transportin a dose- and time-dependent manner. Through the upregulation ofgenes and proteins for ZIP4, MT1, and DMT1, treatment with zinc-sucrosecomplex improved the proportion of absorbed zinc utilized for transportcompared to ZnCl2 (26.21 & PLUSMN; 4.96 versus 8.50 & PLUSMN; 1.51%). Pharmacokinetic analysis of mice confirmed thezinc absorption-promoting effect of zinc-sucrose complex, asindicated by the considerably higher serum zinc level (4.16 & PLUSMN;0.53 versus 2.56 & PLUSMN; 0.45 mg/L) and intestinalZIP4, MT1, and DMT1 gene expression than ZnCl2. Furthertreatment of different zinc channel inhibitors and CETSA demonstratedthe direct interaction of zinc-sucrose complex with ZIP4 proteinand ZIP4-mediated cellular transport of zinc-sucrose complex.These findings provide a novel insight into the zinc absorption-promotingmechanism of zinc-sucrose complex, which could be used as aningredient in functional foods to treat zinc deficiency.

Automated summary

Sucrose is shown to be a stable metal-ion chelating agent that can enhance the absorption of metal ions. This study explores the structure of the zinc-sucrose complex and its ability to promote zinc absorption in cells and mice. The complex increases zinc uptake and transport, upregulates genes and proteins involved in zinc absorption, and interacts with zinc transport proteins. These findings offer valuable insights into the mechanisms of zinc absorption and suggest potential applications in treating zinc deficiency.