Soluble lectin-like oxidized low density lipoprotein receptor-1 in type 2 diabetes mellitus

• Published in: Journal of lipid research 2008-07, Vol.49 (7), p.1438-1444
• Main Authors: Tan, Kathryn C.B., Shiu, Sammy W.M., Wong, Ying, Leng, Lin, Bucala, Richard
• Format: Article
• Language: English
• Subjects: advanced glycation end products; Diabetes Mellitus, Type 2 - blood; Female; Humans; Male; Middle Aged; oxidized LDL; Scavenger Receptors, Class E - blood; Solubility; soluble receptors
• ISSN: 0022-2275; 1539-7262
• DOI: 10.1194/jlr.M700551-JLR200

The lectin-like oxidized low density lipoprotein receptor-1 (LOX-1) can be proteolytically cleaved and released as soluble forms (sLOX-1). We have determined serums LOX-1 in type 2 diabetes and evaluated the effect of glucose and advanced glycation end products (AGEs) on sLOX-1 in vitro and in vivo. Endothelial cells were incubated with glucose or AGEs, and sLOX-1 in cell medium was measured. Serum sLOX-1 was measured in 219 diabetic patients and 187 controls by ELISA. The effect of lowering glucose and AGEs on sLOX-1 was determined in 38 poorly controlled diabetic patients after improvement in glycemic control. Incubation of endothelial cells with AGE-BSA led to a dose-dependent increase in sLOX-1, whereas the effect of glucose on sLOX-1 was less marked. Serum sLOX-1 was 9% higher in diabetic patients compared with controls (P < 0.01). In the poorly controlled patients, serum sLOX-1 decreased by 12.5% after improvement in glycemic control (P < 0.05). The magnitude of reduction in sLOX-1 correlated with the improvement in hemoglobin A1c and AGEs but not with the reduction in oxidized LDL.XXX sLOX-1 level is increased in type 2 diabetes. Both glucose and AGEs are important determinants of LOX-1 expression, and lowering glucose and AGEs leads to a reduction in sLOX-1.