Proliferation of intestinal crypt cells by gastrin-induced ornithine decarboxylase

Abstract

Aim: To determine whether the gastrin stimulated intestinal crypt cell (IEC-6) proliferation by induction of ornithine decarboxylase (ODC).

Methods: IEC-6 cells were grown in DMEM containing 50 mL x L(-1) dialyzed fetal bovine serum for 24h and then were treated with gastrin. The proliferative capability of the cells was monitored subsequently on d 1, 2, 3, and 4 after treatment with MTT assay at aborbance 570 nm.The cellular ODC mRNA expression, ODC activity, and putrescine content were examined by RT-PCR method, radiometric technique and high-performance liquid chromatography(HPLC) analysis respectively after 12h of treatment.

Results: On d1 after exposure of IEC-6 cells to pentagastrin, the proliferation increased initially and reached a peak on d3 at 250 microg x L(-1) concentration. Pentagastrin 500microg x L(-1) increased cell proliferation on day 1 and day 2, and then decreased. Compared with control group, pentagastrin 250 microg x L(-1) increased ODC mRNA level by 1.09-fold (P<0.05), ODC activity by 1.71-fold(P<0.01), and putrescine content 5.30-fold (P<0.01), respectively. Similarly, pentagastrin of 500 microg x L(-1) also increased ODC mRNA level by 1.16-fold (P<0.05), ODC activity 1.63-fold(P<0.05), and putrescine content 4.41-fold (P<0.01), respectively. But there was not significant difference between them.

Conclusion: Gastrin is an agent which promotes IEC-6 cell proliferation involved in regulating ODC activity mechanism.

Figure 1

Gastrin effect on IEC-6 proliferation by the MTT assay. ^aP < 0.05, ^bP < 0.01 vs control.

Figure 2

ODC mRNA levels in IEC-6 cells. ^aP < 0.05, ^bP < 0.01 vs control.

Figure 3

ODC activity in IEC-6 cells exposed to pentagastrin. ^aP < 0.05 vs control.