Adipose tissue from pregnant women with and without gestational diabetes mellitus: insulin-sensitive but resistant to hyperosomolarity.
OBJECTIVE
We sought to determine the contribution of adipose tissue to the insulin resistance of pregnancy. We also investigated whether hyperosmolar stress (induced by sorbitol) stimulates glucose uptake in human adipose tissue and, if so, whether this effect is altered in pregnancy and gestational diabetes mellitus.


METHODS
Subcutaneous and omental adipose tissue biopsy specimens were obtained at elective abdominal surgery or cesarean delivery from 16 normal glucose-tolerant pregnant women, 13 pregnant women with gestational diabetes mellitus, and 19 body mass index-matched nonpregnant control subjects. Basal, insulin (100 nmol/L)-, and sorbitol (250 mmol/L)-stimulated glucose uptake levels were measured.


RESULTS
Basal and insulin-stimulated glucose uptake into adipose tissue was not impaired in pregnancy or gestational diabetes mellitus compared with control subjects. Hyperosmolarity stimulated glucose uptake in human adipose tissue from the subcutaneous, but not omental depot, and not in adipose tissue from pregnant subjects.


CONCLUSIONS
There is no significant difference in insulin sensitivity in adipose tissue from pregnant or nonpregnant women; hyperosmolarity stimulates glucose uptake in subcutaneous adipose tissue from nonpregnant women, and adipose tissue from pregnant women is sorbitol resistant. These findings suggest the phosphotidylinositol 3-kinase-independent pathway may have pathophysiologic relevance to glucose uptake in human adipose tissue and may be impaired in pregnancy.
Russell
Anthony W
AW
Department of Diabetes and Endocrinology, Centre for Diabetes and Endocrine Research, University of Queensland, Brisbane, Australia. arussell@cder.soms.uq.edu.au
McIntyre
H David
HD
Whitehead
Jon P
JP
Prins
Johannes B
JB
D000273:Adipose Tissue / Q000378:metabolism / Q000502:physiology*; D000328:Adult; D016640:Diabetes, Gestational / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D005947:Glucose / Q000378:metabolism; D051275:Glucose Transporter Type 4 / Q000502:physiology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008875:Middle Aged; D009994:Osmolar Concentration; D011247:Pregnancy / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D013012:Sorbitol / Q000494:pharmacology
D051275:Glucose Transporter Type 4; C495692:SLC2A4 protein, human; D013012:Sorbitol; D005947:Glucose