1. Glycogen metabolism in the glucose-sensing and supply-driven β-cell.
- Author
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Andersson, Lotta E., Nicholas, Lisa M., Filipsson, Karin, Sun, Jiangming, Medina, Anya, Al-Majdoub, Mahmoud, Fex, Malin, Mulder, Hindrik, and Spégel, Peter
- Subjects
GLYCOGEN synthases ,INSULIN ,ISLANDS of Langerhans ,GLYCOGENOLYSIS ,LABORATORY rodents - Abstract
Glycogen metabolism in β-cells may affect downstream metabolic pathways controlling insulin release. We examined glycogen metabolism in human islets and in the rodent-derived INS-1 832/13 β-cells and found them to express the same isoforms of key enzymes required for glycogen metabolism. Our findings indicate that glycogenesis is insulin-independent but influenced by extracellular glucose concentrations. Levels of glycogen synthase decrease with increasing glucose concentrations, paralleling accumulation of glycogen. We did not find cAMP-elicited glycogenolysis and insulin secretion to be causally related. In conclusion, our results reveal regulated glycogen metabolism in human islets and insulin-secreting cells. Whether glycogen metabolism affects insulin secretion under physiological conditions remains to be determined. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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