New imaging techniques of fat, muscle and liver within the context of determining insulin sensitivity.
Body fat distribution and ectopic fat deposition are important determinants of insulin sensitivity. Fat deposition in muscle and the liver, in particular, has been found to impair insulin signalling in these insulin-sensitive tissues. Thus, exact quantification of fat content may help to distinguish between different sites of insulin resistance. Increased fat deposition in the visceral compartment compared with the subcutaneous depot also represents an important factor leading to insulin resistance. Recent data clearly showed that visceral fat is a strong determinant of liver fat content. Exact quantification of fat distribution by magnetic resonance imaging and magnetic resonance spectroscopy may help to define distinct 'fat-distribution phenotypes'. This may allow a search for new candidate genes for type 2 diabetes mellitus and identify, at an early stage, individuals at risk for decline in insulin sensitivity.
Stefan
Norbert
N
Department of Internal Medicine, University of Tübingen, Tübingen, Germany. norbert.stefan@med.uni-tuebingen.de
Machann
Jürgen
J
Schick
Fritz
F
Claussen
Claus D
CD
Thamer
Claus
C
Fritsche
Andreas
A
Häring
Hans-Ulrich
HU
D050218:Body Fat Distribution / Q000379:methods; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D006801:Humans; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008099:Liver / Q000000981:diagnostic imaging* / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008297:Male; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging* / Q000378:metabolism; D011859:Radiography