Functional beta-cell maturation is marked by an increased glucose threshold and by expression of urocortin 3. Nat Biotechnol.

Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, Massachusetts, USA.
Nature Biotechnology (Impact Factor: 41.51). 03/2012; 30(3):261-4. DOI: 10.1038/nbt.2141
Source: PubMed


Insulin-expressing cells that have been differentiated from human pluripotent stem cells in vitro lack the glucose responsiveness characteristic of mature beta cells. Beta-cell maturation in mice was studied to find genetic markers that enable screens for factors that induce bona fide beta cells in vitro. We find that functional beta-cell maturation is marked by an increase in the glucose threshold for insulin secretion and by expression of the gene urocortin 3.

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Available from: Christian Schuetz, May 06, 2014
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    • "We therefore interpreted their intracellular Ca2+ pattern as “immature”. Recently, Blum et al. showed that islets from mice older than P9 respond as “mature” β-cells and that β-cell maturation occurs between P2 and P9 [38]. Our results with islets from neonate mice P7 to P9 suggest that the maturity process in terms of Ca2+ signaling has not been fully achieved by P9. "
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    • "The recent identification of a faithful surrogate for functional maturation of b-cells (urocortin 3; Blum et al., 2012) may facilitate this direction of research. "
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    • "In fact, many components of the noradrenergic program were upregulated. A number of these neuronal genes are expressed to some extent early during endocrine pancreas development, but their expression declines significantly by 3 to 4 weeks of age (24). For example, real-time qPCR analysis indicated that the expression of neuropeptide Y (NPY), which is normally downregulated upon maturation, was expressed at high levels in the mutant NC:Dicer1fl/fl pancreata. "
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