Low adipocyte IRS-1 protein expression is associated with an increased arterial stiffness in non-diabetic males.
OBJECTIVE
Low adipocyte IRS-1 protein expression is a biomarker for insulin resistance and early atherosclerosis. However, whether IRS-1 protein expression is related to systemic arterial stiffness, is unknown.


RESULTS
Ten non-diabetic male subjects with low adipocyte IRS-1 protein expression (LIRS) were matched with 10 non-diabetic males with normal IRS-1 protein expression (NIRS). Augmentation index (AIx) and time for reflection of pulse wave (Tr) were studied with pulse wave analysis, both in the fasting state and during a euglycemic hyperinsulinemic clamp. The LIRS-group showed an increased fasting insulin concentration (fP-insulin 71+/-4 pmol/L versus 58+/-5 pmol/L; p=0.02 (mean+/-S.E.)), whereas glucose disposal rate during the clamp (8.7+/-0.8 mg/kg LBM/min versus 10.3+/-1.3 mg/kg LBM/min; n.s.) did not differ significantly. Blood pressure, lipid parameters, adiponectin, endothelin-1 and CRP concentrations were similar. However, in the basal state, AIx was increased (129+/-4% versus 116+/-2%; p<0.02) and Tr was decreased (150+/-3 ms versus 171+/-5 ms; p<0.01), suggesting stiffer vessels in the LIRS-group. The LIRS-group exhibited an attenuated AIx response to hyperinsulinemia compared to the NIRS-group.


CONCLUSIONS
The data suggest that non-obese non-diabetic men with a low adipocyte IRS-1 protein expression have an increased systemic arterial stiffness.
Sandqvist
Madeléne
M
The Lundberg Laboratory for Diabetes Research, Department of Internal Medicine, Sahlgrenska Academy at Göteborg University, Sahlgrenska University Hospital, Blå Stråket 5, SE-413 45 Göteborg, Sweden. madelene.sandqvist@medic.gu.se
Nyberg
Gunnar
G
Hammarstedt
Ann
A
Klintland
Natalia
N
Gogg
Silvia
S
Caidahl
Kenneth
K
Ahrén
Bo
B
Smith
Ulf
U
Jansson
Per-Anders
PA
D017667:Adipocytes / Q000378:metabolism*; D052242:Adiponectin; D000328:Adult; D001161:Arteriosclerosis / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001786:Blood Glucose; D002097:C-Reactive Protein / Q000378:metabolism; D003920:Diabetes Mellitus; D019332:Endothelin-1 / Q000097:blood; D005215:Fasting; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000378:metabolism; D055504:Insulin Receptor Substrate Proteins; D007333:Insulin Resistance; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D010750:Phosphoproteins / Q000378:metabolism*
D052242:Adiponectin; D015415:Biomarkers; D001786:Blood Glucose; D019332:Endothelin-1; C526292:IRS1 protein, human; D055504:Insulin Receptor Substrate Proteins; D036341:Intercellular Signaling Peptides and Proteins; D010750:Phosphoproteins; D002097:C-Reactive Protein