Linked Life Data

11518822

Source:http://linkedlifedata.com/resource/pubmed/id/11518822

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-23
pubmed:abstractText
Hyperinsulinism and hyperammonemia syndrome has been reported as a cause of moderately severe hyperinsulinism with diffuse involvement of the pancreas. The disorder is caused by gain of function mutations in the GLUD1 gene, resulting in a decreased inhibitory effect of guanosine triphosphate on the glutamate dehydrogenase (GDH) enzyme. Twelve unrelated patients (six males, six females) with hyperinsulinism and hyperammonemia syndrome have been investigated. The phenotypes were clinically heterogeneous, with neonatal and infancy-onset hypoglycemia and variable responsiveness to medical (diazoxide) and dietary (leucine-restricted diet) treatment. Hyperammonemia (90-200 micromol/L, normal <50 micromol/L) was constant and not influenced by oral protein, by protein- and leucine-restricted diet, or by sodium benzoate or N-carbamylglutamate administration. The patients had mean basal GDH activity (18.3 +/- 0.9 nmol/min/mg protein) not different from controls (17.9 +/- 1.8 nmol/min/mg protein) in cultured lymphoblasts. The sensitivity of GDH activity to inhibition by guanosine triphosphate was reduced in all patient lymphoblast cultures (IC(50), or concentrations required for 50% inhibition of GDH activity, ranging from 140 to 580 nM, compared with control IC(50) value of 83 +/- 1.0 nmol/L). The allosteric effect of ADP was within the normal range. The activating effect of leucine on GDH activity varied among the patients, with a significant decrease of sensitivity that was correlated with the negative clinical response to a leucine-restricted diet in plasma glucose levels in four patients. Molecular studies were performed in 11 patients. Heterozygous mutations were localized in the antenna region (four patients in exon 11, two patients in exon 12) as well as in the guanosine triphosphate binding site (two patients in exon 6, two patients in exon 7) of the GLUD1 gene. No mutation has been found in one patient after sequencing the exons 5-13 of the gene.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0031-3998
pubmed:author
pubmed:issnType
Print
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
353-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Hyperinsulinism and hyperammonemia syndrome: report of twelve unrelated patients.
pubmed:affiliation
Departments of Pediatrics, Hôpital Necker-Enfants malades, Paris, France.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't