All issues > Volume 44(5); 2001

Original Article

J Korean Pediatr Soc. 2001;44(5):523-532. Published online May 15, 2001.

Studies on Functional Differentiation of Small Intestinal Epithelial Cells

Ho Keun HK Yi¹, Su Mi SM Oh², Dae Yeol DY Lee¹, Jung Soo JS Kim², Pyoung Han PH Hwang¹

¹Research Institute of Clinical Medicine, College of Medicine, Chonbuk National University, Chonju, Korea
²Department of Pediatrics, College of Medicine, Chonbuk National University, Chonju, Korea

Correspondence Pyoung Han PH Hwang ,Email: hwaph@moak.chonbuk.ac.kr

Abstract

Purpose
: We investigated compounds from food sources given to children that may induce the differentiation of small intestinal epithelial cells in order to signal pathways that induce the proliferation and differentiation of small intestinal epithelial cells.
Methods
: We analyzed small intestinal epithelial cell differentiation using in vitro IEC-6 cells model. The growth curve of IEC-6 cells was obtained by standard MTT assay. Alkaline phosphatase(ALP) activities were determined using the paranitrophenol colorimetric assay for the differentiation of IEC-6 cells. We did ALP and Brdu double-staining of cultured IEC-6 cells to distinguish between differentiation and proliferation, and investigated compounds' potential for inducing differentiation of small intestinal epithelial cells and protein kinase signal pathway.
Results
: The calcium ion was essential for the differentiation of IEC-6 cells. Retinol and retinoic acid induced the differentiation of IEC-6 cells. β-LG stabilized and increased cell permeation of retinoic acid. IEC-6 cells showed 3 or 4 times more ALP activity with co-treatment of retinoic acid and β-LG. BSA and OVA accelerated differentiation of IEC-6 cells in a similiar fashion to β-LG. But, pepton and casein didn't. Heat destruction of β-LG, BSA and OVA lead to loss in the ability of these compounds to induce cellular differentiation. The PKA signal pathway involved differentiation of IEC-6 cells. IEC-6 cells proliferation increased by the activation of PKC signal pathway and decreased differentiation by PKC signal pathway.
Conclusion
: Our results confirm that signal pathways are related to the proliferation and differentiation of small intestinal epithelial cells and various compounds from food sources of childhood, such as β-LG, BSA, OVA, and retinoic acid. These compounds appear to induce differentiation of small intestinal epithelial cells and may play a role in stimulating regeneration of epithelial cells after small intestinal mucosal injury.

Keywords :Functional differentiation, IEC-6, Small intestinal epithelial cells