TY - JOUR
T1 - PED/PEA-15 regulates glucose-induced insulin secretion by restraining potassium channel expression in pancreatic β-cells
AU - Miele, Claudia
AU - Raciti, Gregory Alexander
AU - Cassese, Angela
AU - Romano, Chiara
AU - Giacco, Ferdinando
AU - Oriente, Francesco
AU - Paturzo, Flora
AU - Andreozzi, Francesco
AU - Zabatta, Assunta
AU - Troncone, Giancarlo
AU - Bosch, Fatima
AU - Pujol, Anna
AU - Chneiweiss, Hervé
AU - Formisano, Pietro
AU - Beguinot, Francesco
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2007/3
Y1 - 2007/3
N2 - The phosphoprotein enriched in diabetes/phosphoprotein enriched in astrocytes (ped/pea-15) gene is overexpressed in human diabetes and causes this abnormality in mice. Transgenic mice with β-cell-specific overexpression of ped/pea-15 (β-tg) exhibited decreased glucose tolerance but were not insulin resistant. However, they showed impaired insulin response to hyperglycemia. Islets from the β-tg also exhibited little response to glucose. mRNAs encoding the Sur1 and Kir6.2 potassium channel subunits and their upstream regulator Foxa2 were specifically reduced in these islets. Overexpression of PED/PEA-15 inhibited the induction of the atypical protein kinase C (PKC)-ζ by glucose in mouse islets and in β-cells of the MIN-6 and INS-1 lines. Rescue of PKC-ζ activity elicited recovery of the expression of the Sur1, Kir6.2, and Foxa2 genes and of glucose-induced insulin secretion in PED/PEA-15-overexpressing β-cells. Islets from ped/pea-15-null mice exhibited a twofold increased activation of PKC-ζ by glucose; increased abundance of the Sur1, Kir6.2, and Foxa2 mRNAs; and enhanced glucose effect on insulin secretion. In conclusion, PED/PEA-15 is an endogenous regulator of glucose-induced insulin secretion, which restrains potassium channel expression in pancreatic β-cells. Overexpression of PED/PEA-15 dysregulates β-cell function and is sufficient to impair glucose tolerance in mice.
AB - The phosphoprotein enriched in diabetes/phosphoprotein enriched in astrocytes (ped/pea-15) gene is overexpressed in human diabetes and causes this abnormality in mice. Transgenic mice with β-cell-specific overexpression of ped/pea-15 (β-tg) exhibited decreased glucose tolerance but were not insulin resistant. However, they showed impaired insulin response to hyperglycemia. Islets from the β-tg also exhibited little response to glucose. mRNAs encoding the Sur1 and Kir6.2 potassium channel subunits and their upstream regulator Foxa2 were specifically reduced in these islets. Overexpression of PED/PEA-15 inhibited the induction of the atypical protein kinase C (PKC)-ζ by glucose in mouse islets and in β-cells of the MIN-6 and INS-1 lines. Rescue of PKC-ζ activity elicited recovery of the expression of the Sur1, Kir6.2, and Foxa2 genes and of glucose-induced insulin secretion in PED/PEA-15-overexpressing β-cells. Islets from ped/pea-15-null mice exhibited a twofold increased activation of PKC-ζ by glucose; increased abundance of the Sur1, Kir6.2, and Foxa2 mRNAs; and enhanced glucose effect on insulin secretion. In conclusion, PED/PEA-15 is an endogenous regulator of glucose-induced insulin secretion, which restrains potassium channel expression in pancreatic β-cells. Overexpression of PED/PEA-15 dysregulates β-cell function and is sufficient to impair glucose tolerance in mice.
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U2 - 10.2337/db06-1260
DO - 10.2337/db06-1260
M3 - Article
C2 - 17327429
AN - SCOPUS:33847388518
SN - 0012-1797
VL - 56
SP - 622
EP - 633
JO - Diabetes
JF - Diabetes
IS - 3
ER -
