PDX-1 expression in pancreatic ductal cells after partial pancreatectomy in adult rats

Abstract

To investigate the protein and mRNA expression of pancreas/duodenal homeobox-1 (PDX-1), a transcription factor as a marker for pancreatic stem cells, in pancreatic ductal cells of rats after partial (90%) pancreatectomy and evaluated the significance of the PDX-1 expression. Western blot and Reverse transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of PDX-1 protein and mRNA respectively. PDX-1 protein was only faintly detected in pancreatic ductal cells on the day 1 after partial pancreatectomy. On the day 2 and 3 after operation in operation group, a 2–3 fold increased PDX-1 protein was observed, corresponding to the characteristic 42-kD protein in Western blot. There was significant difference between operation group and sham-operation group (P<0.05). PDX-1 protein expression on the day 5 and 7 after operation had already been no difference from control group (P>0.05). RT-PCR revealed the PDX-1 mRNA expression showed no significant difference between operation group at various time points and sham-operation group (P>0.05). These results indicate that there was overexpression of PDX-1 in the cells of pancreatic epithelium during the regeneration of remnant pancreas after partial pancreatectomy in adult rats, suggesting the pancreatic stem cells in pancreatic ductal epithelial cells are involved in the regeneration of remnant pancreas and the expression of PDX-1 in ductal cells was regulated posttranscription.

Keywords

pancreas/duodenal homeobox-1 / pancreatic epithelium / ductal cells / rats

References

[1] Bonner-WeirS. Stem cells in diabetes: what has been achieved. Horm Res, 2003, 60(Suppl 3): 10-10

[2] SharmaA, ZangenD H, ReitzP, et al.. The homeodomain protein IDX-1 increases after an early burst of proliferation during pancreatic regeneration. Diabetes, 1999, 48: 507-507

[3] ZulewskiH, AbrahamE J, GerlachM J, et al.. Multipotential nestin-positive stem cells isolated from adult pancreatic islets differentiate ex vivo into pancreatic endocrine, exocrine, and hepatic phenotypes. Diabetes, 2001, 50: 521-521

[4] GuG, DubauskaiteJ, MeltonD A. Direct evidence for the pancreatic lineage: NGN3+ cells are islet progenitors and are distinct from duct progenitors. Development, 2002, 129: 2447-2447

[5] PetropavlovskaiaM, RosenbergL. Identification and characterization of small cells in the adult pancreas: potential progenitor cells?. Cell Tissue Res, 2002, 310: 51-51

[6] EdlundH. Developmental biology of the pancreas. Diabetes, 2001, 50: 5-5

[7] DuttaS, GannonM, PeersB, et al.. PDX: PBX complexes are required for normal proliferation of pancreatic cells during development. Proc Natl Acad Sci USA, 2001, 98: 1065-1065

[8] JonssonJ, CarlssonL, EdlundT, et al.. Insulin-promoter-factor 1 is required for pancreas development in mice. Nature, 1994, 371: 606-606

[9] HosotaniR, IdaJ, KogireM, et al.. Expression of pancreatic duodenal hoemobox-1 in pancreatic islet neogenesis after surgical wrapping in rats. Surgery, 2004, 135: 297-297