Effect of Passage Number and Culture Time on the Expression and Activity of Insulin-Degrading Enzyme in Caco-2 Cells

Background: Insulin-degrading enzyme (IDE) is a conserved zinc metallopeptidase. Here, we have evaluated the effect of passage number and culture time on IDE expression and activity in colorectal adenocarcinoma cell line (Caco-2). Methods: Caco-2 cells were cultured with different passage ranges of 5-15, 25-35, 52-63 for 48, 72, and 120 hours. Subsequently, IDE expression and enzyme activity were assessed by Western blot analysis and fluorescent assay, respectively. Results: Our results confirmed that the amount of IDE was higher in cell extract compared to supernatant, and different passage numbers and culture times had small effect on IDE expression. However, when cells were cultured in the passage number range of 5-15 for 72 hours, the IDE activity was 35% higher compared to other passage numbers (p < 0.05). Conclusion: The use of Caco-2 cells at passage number range of 5-15 and culture time of 72 hours provides proper conditions for IDE-related studies.