| First Author | Nakamura K | Year | 2011 |
| Journal | Biomed Res | Volume | 32 |
| Issue | 2 | Pages | 167-74 |
| PubMed ID | 21551953 | Mgi Jnum | J:171567 |
| Mgi Id | MGI:4950462 | Doi | 10.2220/biomedres.32.167 |
| Citation | Nakamura K, et al. (2011) Pancreatic beta-cells are generated by neogenesis from non-beta-cells after birth. Biomed Res 32(2):167-74 |
| abstractText | The mass of pancreatic beta-cells is maintained throughout lifetime to control blood glucose levels. Although the major mechanism of the maintenance of beta-cell mass after birth is thought to be selfreplication of pre-existing beta-cells, it is possible that pancreatic beta-cells are also generated from non-beta-cells. Here, we address this issue by using the inducible Cre/loxP system to trace beta-cells. We generated Ins2-CreERT2/R26R-YFP double knock-in mice, in which pancreatic beta-cells can be labeled specifically and permanently upon injection of the synthetic estrogen analog tamoxifien, and then traced the beta-cells by pulse and chase experiment in several different conditions. When beta-cells were labeled in adults under physiological and untreated conditions, the frequency of the labeling (labeling index) was not altered significantly throughout the 12-month experimental period. In addition, the labeling index was not changed after ablation of beta-cells by streptozotocin treatment. However, when tamoxifen was injected to pregnant mothers just before they gave birth, the labeling index in the neonates was decreased significantly around weaning, suggesting that beta-cells are generated from non-beta-cells. These results indicate that various mechanisms are involved in the maintenance of beta-cells after birth, and that the present system using knock-in mice is useful for investigation of beta-cell fate. |
