en بیوشیمی Biochemistry Research Article Research Article <span style="font-size:12px;"><span style="font-family:Times New Roman;"><b>Background:</b> Certain trace elements, like cerium, have the potential to disrupt iron metabolism. This study explored the impact of cerium on intestinal iron absorption, focusing on the initial stage of iron metabolism. We employed the rat everted gut sac (EGS) segments to assess the interference caused by cerium. The primary objectives of this study were to examine the absorption of cerium in the intestines and to compare iron absorption in the presence and absence of cerium.<br> <b>Methods:</b> For the EGS experiment, segments of the rat&#39;s duodenum, ileum, or jejunum were promptly excised, cut into 5-6 cm segments, and rinsed with a physiological solution. These freshly prepared rat EGS segments were then incubated in Earle&#39;s medium containing iron (III) and/or cerium (III). We examined the impact of ascorbic acid, glucose, and different time intervals on the intestinal absorption of cerium and iron. Specifically, we investigated how glucose (5 mM) and ascorbic acid (2.8 mM) affected the absorption of cerium and iron at various concentrations (ranging from 0 to 200 mg/L). Additionally, we assessed the interfering effect of cerium on iron absorption.<br> <b>Results:</b> The results indicated that the maximum intestinal absorption of Fe (III) and Ce (III) occurred at a concentration of 200 mg/L. Furthermore, it was observed that their uptake increased following the reduction by ascorbic acid. The absorption of these elements also rose in the presence of glucose, suggesting energy-dependent transport. Additionally, a consistent cerium concentration was found to decrease iron absorption by 24.3% (P &le; 0.05).<br> <b>Conclusion</b>: Based on the results, cerium likely reduces iron uptake by competing with iron. Cerium can also disrupt iron metabolism and lead to iron-related metabolic disorders. However, further studies at the molecular and intracellular levels are needed to gain a better understanding of this mechanism.</span></span><br> &nbsp; Iron, Cerium, Trace Elements, Intestinal Absorption, Iron Metabolism Disorders 32 35 http://mlj.goums.ac.ir/browse.php?a_code=A-10-1075-1&slc_lang=en&sid=1 Fereshteh Hematyar Tabatabaie Fereshte.hematyar@gmail.com 100319475328460027462 100319475328460027462 No Department of Biochemistry, Falavarjan Branch.Islamic Azad University, Isfahan, Iran Ali Asghar Moshtaghie moshtaghie@Pharm.mui.ac.ir 100319475328460027463 100319475328460027463 Yes Department of Biochemistry, Falavarjan Branch.Islamic Azad University, Isfahan, Iran Ali Asghar Rastegari rastegari@iaufala.ac.ir 100319475328460027464 100319475328460027464 No Department of Biochemistry, Falavarjan Branch.Islamic Azad University, Isfahan, Iran Hashem Nayeri hnaieri@gmail.com 100319475328460027465 100319475328460027465 No Department of Biochemistry, Falavarjan Branch.Islamic Azad University, Isfahan, Iran