Transendothelial lipoprotein exchange and microalbuminuria.
OBJECTIVE
Microalbuminuria associates with increased risk of atherosclerosis in individuals without diabetes. We hypothesized that transendothelial lipoprotein exchange is elevated among such individuals, possibly explaining increased intimal lipoprotein accumulation and thus atherosclerosis.


METHODS
Using an in vivo isotope technique, transendothelial exchange of low density lipoprotein (LDL) was measured in 77 non-diabetic individuals. Autologous 131-iodinated LDL was reinjected intravenously, and the 1-h fractional escape rate was calculated as index of transendothelial exchange.


RESULTS
There was no difference in transendothelial LDL exchange between subjects with microalbuminuria versus normoalbuminuria (mean (95% confidence interval) 3.8%/h (3.3-4.3%/h) versus 4.2%/h (3.7-4.7%/h); P=0.33). In contrast, there was a positive correlation between transendothelial LDL exchange and (logarithmically transformed) plasma insulin: beta=0.6 (95% CI: 0.1-1.1); R=0.22; P<0.05. This correlation was independent of age, sex, blood pressure, plasma concentration of lipoproteins, LDL size, body mass index, plasma volume, and use of medicine, and it was unlikely caused by altered hepatic LDL receptor expression, or glycosylation of LDL.


CONCLUSIONS
In non-diabetic individuals, transendothelial LDL exchange is not associated with microalbuminuria, but possibly with hyperinsulinemia.
Jensen
Jan Skov
JS
Department of Nephrology and Endocrinology P., The National University Hospital, Copenhagen, Denmark. jsje@c.dk
Feldt-Rasmussen
Bo
B
Jensen
Kurt Svarre
KS
Clausen
Peter
P
Scharling
Henrik
H
Nordestgaard
Børge Grønne
BG
D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000150:complications / Q000378:metabolism*; D001161:Arteriosclerosis / Q000150:complications / Q000378:metabolism; D002199:Capillary Permeability; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004730:Endothelium, Vascular / Q000378:metabolism*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis
D007328:Insulin; D008077:Lipoproteins, LDL