| Autor: |
Yasuharu Ohta, Akihiko Taguchi, Takuro Matsumura, Hiroko Nakabayashi, Masaru Akiyama, Kaoru Yamamoto, Ruriko Fujimoto, Risa Suetomi, Akie Yanai, Koh Shinoda, Yukio Tanizawa |
| Jazyk: |
angličtina |
| Rok vydání: |
2017 |
| Předmět: |
|
| Zdroj: |
EBioMedicine, Vol 18, Iss C, Pp 146-156 (2017) |
| Druh dokumentu: |
article |
| ISSN: |
2352-3964 |
| DOI: |
10.1016/j.ebiom.2017.03.040 |
| Popis: |
In Wfs1−/− Ay/a islets, in association with endoplasmic reticulum (ER) stress, D-site-binding protein (Dbp) expression decreased and Nuclear Factor IL-3 (Nfil3)/E4 Promoter-binding protein 4 (E4bp4) expression increased, leading to reduced DBP transcriptional activity. Similar alterations were observed with chemically-induced ER stress. Transgenic mice expressing E4BP4 under the control of the mouse insulin I gene promoter (MIP), in which E4BP4 in β-cells is expected to compete with DBP for D-box, displayed remarkable glucose intolerance with severely impaired insulin secretion. Basal ATP/ADP ratios in MIP-E4BP4 islets were elevated without the circadian oscillations observed in wild-type islets. Neither elevation of the ATP/ADP ratio nor an intracellular Ca2+ response was observed after glucose stimulation. RNA expressions of genes involved in insulin secretion gradually increase in wild-type islets early in the feeding period. In MIP-E4BP4 islets, however, these increases were not observed. Thus, molecular clock output DBP transcriptional activity, susceptible to ER stress, plays pivotal roles in β-cell priming for insulin release by regulating β-cell metabolism and gene expressions. Because ER stress is also involved in the β-cell failure in more common Type-2 diabetes, understanding the currently identified ER stress-associated mechanisms warrants novel therapeutic and preventive strategies for both rare form and common diabetes. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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