| First Author | Okamoto M | Year | 2008 |
| Journal | Diabetologia | Volume | 51 |
| Issue | 5 | Pages | 827-35 |
| PubMed ID | 18369586 | Mgi Jnum | J:137933 |
| Mgi Id | MGI:3803415 | Doi | 10.1007/s00125-008-0944-9 |
| Citation | Okamoto M, et al. (2008) Adiponectin induces insulin secretion in vitro and in vivo at a low glucose concentration. Diabetologia 51(5):827-35 |
| abstractText | AIMS/HYPOTHESIS: A decrease in plasma adiponectin levels has been shown to contribute to the development of diabetes. However, it remains uncertain whether adiponectin plays a role in the regulation of insulin secretion. In this study, we investigated whether adiponectin may be involved in the regulation of insulin secretion in vivo and in vitro. METHODS: The effect of adiponectin on insulin secretion was measured in vitro and in vivo, along with the effects of adiponectin on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentration and state of 5'-AMP-activated protein kinase (AMPK). In addition, insulin granule transport was measured by membrane capacitance and total internal reflection fluorescence (TIRF) analysis. RESULTS: Adiponectin significantly stimulated insulin secretion from pancreatic islets to approximately 2.3-fold the baseline value in the presence of a glucose concentration of 5.6 mmol/l. Although adiponectin had no effect on ATP generation, membrane potentials, Ca2+ currents, cytosolic calcium concentrations or activation status of AMPK, it caused a significant increase of membrane capacitance to approximately 2.3-fold the baseline value. TIRF analysis revealed that adiponectin induced a significant increase in the number of fusion events in mouse pancreatic beta cells under 5.6 mmol/l glucose loading, without affecting the status of previously docked granules. Moreover, intravenous injection of adiponectin significantly increased insulin secretion to approximately 1.6-fold of baseline in C57BL/6 mice. CONCLUSIONS/INTERPRETATION: The above results indicate that adiponectin induces insulin secretion in vitro and in vivo. |
