Article

Low adipocyte IRS-1 protein expression is associated with an increased arterial stiffness in non-diabetic males.

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.
Atherosclerosis (impact factor: 3.79). 05/2005; 180(1):119-25. DOI:10.1016/j.atherosclerosis.2004.11.006 pp.119-25
Source: PubMed

ABSTRACT 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.
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.
The data suggest that non-obese non-diabetic men with a low adipocyte IRS-1 protein expression have an increased systemic arterial stiffness.

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    Silvia Gogg, Ulf Smith, Per-Anders Jansson
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    Diabetes 08/2009; 58(10):2238-45. · 8.29 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

10 non-diabetic males
 
atherosclerosis
 
attenuated AIx response
 
basal state
 
euglycemic hyperinsulinemic clamp
 
glucose disposal rate
 
increased fasting insulin concentration
 
increased systemic arterial stiffness
 
insulin resistance
 
IRS-1 protein expression
 
lipid parameters
 
LIRS-group
 
LIRS-group exhibited
 
Low adipocyte IRS-1 protein expression
 
NIRS
 
NIRS-group
 
non-diabetic male subjects
 
normal IRS-1 protein expression
 
stiffer vessels
 
systemic arterial stiffness