Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
52
pubmed:dateCreated
2007-12-24
pubmed:abstractText
Hereditary hemochromatosis is an inherited disorder of increased iron absorption that can result in cirrhosis, diabetes, and other morbidities. We have investigated the mechanisms underlying supranormal glucose tolerance despite decreased insulin secretion in a mouse model of hemochromatosis with deletion of the hemochromatosis gene (Hfe(-/-)). Hfe(-/-) mice on 129Sv or C57BL/6J backgrounds have decreased glucose excursions after challenge compared with controls. In the C57BL/6J/ Hfe(-/-), for example, incremental area under the glucose curve is reduced 52% (p < 0.001) despite decreased serum insulin, and homeostasis model assessment insulin resistance is decreased 50% (p < 0.05). When studied by the euglycemic clamp technique 129Sv/Hfe(-/-) mice exhibit a 20% increase in glucose disposal (p < 0.05) at submaximal insulin but no increase at maximal insulin compared with wild types. [1,2-(13)C]D-glucose clearance from plasma is significantly increased in Hfe(-/-) mice (19%, p < 0.05), and lactate derived from glycolysis is elevated 5.1-fold in Hfe(-/-) mice (p < 0.0001). Basal but not insulin-stimulated glucose uptake is elevated in isolated soleus muscle from Hfe(-/-) mice (p < 0.03). Compared with controls Hfe(-/-) mice exhibit no differences in serum lipid, insulin, glucagon, or thyroid hormone levels; adiponectin levels are elevated 41% (p < 0.05), and the adiponectin message in adipocytes is increased 83% (p = 0.04). Insulin action measured by phosphorylation of Akt is not enhanced in muscle, but phosphorylation of AMP-dependent kinase is increased. We conclude that supranormal glucose tolerance in iron overload is characterized by increased glucose disposal that does not result from increased insulin action. Instead, the Hfe(-/-) mice demonstrate increased adiponectin levels and activation of AMP-dependent kinase.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
282
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37501-7
pubmed:dateRevised
2011-3-4
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Increased glucose disposal and AMP-dependent kinase signaling in a mouse model of hemochromatosis.
pubmed:affiliation
Department of Biochemistry, the University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, N.I.H., Extramural