Measurement of selective effect of insulin on glucose disposal from labeled glucose oral test minimal model.
The oral glucose minimal model (OMM) measures insulin sensitivity (S(I)) and the glucose rate of appearance (R(a)) of ingested glucose in the presence of physiological changes of insulin and glucose concentrations. However, S(I) of OMM measures the overall effect of insulin on glucose utilization and glucose production. In this study we show that, by adding a tracer to the oral dose, e.g., of a meal, and by using the labeled version of OMM, OMM* to interpret the data, one can measure the selective effect of insulin on glucose disposal, S(I)*. Eighty-eight individuals underwent both a triple-tracer meal with the tracer-to-tracee clamp technique, providing a model-independent reference of the R(a) of ingested glucose (R(a meal)(ref)) and an insulin-modified labeled intravenous glucose tolerance test (IVGTT*). We show that OMM* provides not only a reliable means of tracing the R(a) of ingested glucose (R(a meal)) but also accurately measures S(I)*. We do so by comparing OMM* R(a meal) with the model-independent R(a meal)(ref) provided by the tracer-to-tracee clamp technique, while OMM* S(I)* is compared with both S(I)(* ref), obtained by using as known input R(a meal)(ref), and with S(I)* measured during IVGTT*.
Dept. of Information Engineering, Univ. of Padova, Via Gradenigo 6/B, I-35131 Padua, Italy.
Chiara
C
Dalla Man
Andrea
A
Caumo
Rita
R
Basu
Robert
R
Rizza
Gianna
G
Toffolo
Claudio
C
Cobelli
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism*; D002247:Carbon Isotopes; D003903:Deuterium; D005260:Female; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D007328:Insulin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D014316:Tritium
D001786:Blood Glucose; D002247:Carbon Isotopes; D007328:Insulin; D014316:Tritium; D003903:Deuterium