Circulating adhesion molecules in humans: role of hyperglycemia and hyperinsulinemia.
BACKGROUND
We assessed the role of glucose and insulin in the regulation of circulating levels of soluble intercellular adhesion molecule-1 (sICAM-1) and vascular adhesion molecule-1 (sVCAM-1) in normal subjects and in patients with type 2 diabetes.


RESULTS
Plasma glucose concentrations were acutely raised in 10 normal subjects and 10 newly diagnosed, complication-free type 2 diabetic patients and maintained at 15 mmol/L for 2 hours. In normal subjects, plasma sICAM-1, but not sVCAM-1, levels rose significantly (P<0.01) at 1 hour and returned to basal values at 2 hours. In another study, octreotide was infused during the hyperglycemic clamp to block the release of endogenous insulin; this prevented the late fall of plasma sICAM-l levels observed in under control clamp conditions. The diabetic patients had plasma sICAM-1 levels significantly higher (P<0.01) than those of the control subjects; plasma sVCAM-1 levels were similar. Both sICAM-l and sVCAM-1 concentrations did not change significantly during the control hyperglycemic clamp; however, octreotide infusion increased plasma sICAM-1 levels, which remained significantly (P<0.05) above baseline during the whole clamp. In an additional 10 type 2 diabetic patients, overnight euglycemia (plasma glucose 5.5 mmol/L) obtained with the aid of an artificial pancreas or supplementation with l-arginine (10 g PO for 30 days), the natural precursor of NO, normalized the increased plasma sICAM-1 levels.


CONCLUSIONS
Acute hyperglycemia increases circulating sICAM-1 levels in normal subjects, whereas the correction of hyperglycemia with insulin or l-arginine supplementation restored to normal levels the increased plasma sICAM-1 levels of type 2 diabetic patients.
Marfella
R
R
Department of Geriatrics, Second University of Naples, Naples, Italy.
Esposito
K
K
Giunta
R
R
Coppola
G
G
De Angelis
L
L
Farzati
B
B
Paolisso
G
G
Giugliano
D
D
D000328:Adult; D001120:Arginine / Q000627:therapeutic use; D002940:Circadian Rhythm; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000188:drug therapy; D005260:Female; D015309:Glucose Clamp Technique; D006801:Humans; D006943:Hyperglycemia / Q000097:blood*; D006946:Hyperinsulinism / Q000097:blood*; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012995:Solubility; D019010:Vascular Cell Adhesion Molecule-1 / Q000097:blood*
D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D001120:Arginine