Glycated low density lipoprotein catabolism is increased in rabbits with alloxan-induced diabetes mellitus.
Hyperglycaemia in diabetes mellitus is responsible for the process of non-enzymatic glycosylation of different proteins. Since we did not find elevated glycated apolipoprotein B levels in diabetic patients, an altered glycated apolipoprotein B metabolism was suspected in diabetic patients. Experiments in normal rabbits showed that non-reductive (in vitro) glycated low density lipoprotein (gly-LDL) was cleared at a slower rate than control LDL and thus stayed longer in the circulation (vascular mean residence time: 10 vs 8 h, p less than 0.001). The body mean residence time for gly-LDL was 22 h vs 17 h for control LDL. In diabetic animals the catabolic parameters of both LDL preparations changed towards a faster clearance, the effect being greatest for gly-LDL (total mean residence times of gly-LDL pre-diabetic: 19 h, diabetic: 16 h; control LDL pre-diabetic and diabetic: 14 h). The difference in clearance between glycated and control LDL was thus strongly reduced. Virtually no antibody complexed to gly-LDL could be measured. The results suggest an increased activity of the non-receptor mediated pathway in diabetes mellitus, possibly co-responsible for an increased atherosclerotic risk.
Kortlandt
W
W
Department of Clinical Chemistry, University Hospital, Utrecht, The Netherlands.
Benschop
C
C
van Rijn
H J
HJ
Erkelens
D W
DW
D000818:Animals; D001055:Apolipoproteins B / Q000097:blood; D002784:Cholesterol / Q000097:blood; D003921:Diabetes Mellitus, Experimental / Q000097:blood*; D006442:Glycated Hemoglobin / Q000378:metabolism; D017127:Glycation End Products, Advanced; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D011817:Rabbits; D012016:Reference Values; D014280:Triglycerides / Q000097:blood; D000093844:Glycated Proteins
D001055:Apolipoproteins B; D002784:Cholesterol; D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D008077:Lipoproteins, LDL; D014280:Triglycerides; C031797:glycated lipoproteins, LDL; D000093844:Glycated Proteins