Congenital hyperinsulinism caused by hexokinase I expression or glucokinase-activating mutation in a subset of β-cells.

Details

Serval ID
serval:BIB_638B23C801DE
Type
Article: article from journal or magazin.
Collection
Publications
Title
Congenital hyperinsulinism caused by hexokinase I expression or glucokinase-activating mutation in a subset of β-cells.
Journal
Diabetes
Author(s)
Henquin J.C., Sempoux C., Marchandise J., Godecharles S., Guiot Y., Nenquin M., Rahier J.
ISSN
1939-327X (Electronic)
ISSN-L
0012-1797
Publication state
Published
Issued date
2013
Volume
62
Number
5
Pages
1689-1696
Language
english
Notes
Publication types: Case Reports ; Journal ArticlePublication Status: ppublish
Abstract
Congenital hyperinsulinism causes persistent hypoglycemia in neonates and infants. Most often, uncontrolled insulin secretion (IS) results from a lack of functional K(ATP) channels in all β-cells or only in β-cells within a resectable focal lesion. In more rare cases, without K(ATP) channel mutations, hyperfunctional islets are confined within few lobules, whereas hypofunctional islets are present throughout the pancreas. They also can be cured by selective partial pancreatectomy; however, unlike those with a K(ATP) focal lesion, they show clinical sensitivity to diazoxide. Here, we characterized in vitro IS by fragments of pathological and adjacent normal pancreas from six such cases. Responses of normal pancreas were unremarkable. In pathological region, IS was elevated at 1 mmol/L and was further increased by 15 mmol/L glucose. Diazoxide suppressed IS and tolbutamide antagonized the inhibition. The most conspicuous anomaly was a large stimulation of IS by 1 mmol/L glucose. In five of six cases, immunohistochemistry revealed undue presence of low-K(m) hexokinase-I in β-cells of hyperfunctional islets only. In one case, an activating mutation of glucokinase (I211F) was found in pathological islets only. Both abnormalities, attributed to somatic genetic events, may account for inappropriate IS at low glucose levels by a subset of β-cells. They represent a novel cause of focal congenital hyperinsulinism.
Keywords
Amino Acid Substitution, Diazoxide/diagnostic use, Glucokinase/genetics, Glucokinase/metabolism, Hexokinase/genetics, Hexokinase/metabolism, Humans, Hyperinsulinism/congenital, Hyperinsulinism/genetics, Hypoglycemic Agents/diagnostic use, Infant, Newborn, Insulin/blood, Insulin/secretion, Insulin-Secreting Cells/drug effects, Insulin-Secreting Cells/metabolism, Mutation, Tolbutamide/diagnostic use
Pubmed
Web of science
Open Access
Yes
Create date
26/01/2015 11:36
Last modification date
20/08/2019 14:20
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