The role of circulating lipoprotein lipase and adiponectin on the particle size of remnant lipoproteins in patients with diabetes mellitus and metabolic syndrome

The majority of lipoprotein lipase in plasma is bound to remnant lipoproteins: A new definition of remnant lipoproteins

“…Namely, a smaller amount of LPL dimers are carried by larger RLP particles compared to a smaller RLP particles which carry a larger amount of LPL dimers per se. We reported previously that the LPL dimers in plasma were inversely correlated with the RLP concentration and particle size in patients with diabetes and MetS [32,33]. As the RLP-TG/RLP-C ratio reflects the RLP particle size [51], we also reported the finding of a significant increase of the RLP-TG/RLP-C ratio after a fat load [52,53].…”

“…However, the LPL activity in the post-heparin plasma has been known to be generally unstable and non-physiological compared to the LPL protein concentration in pre-heparin plasma. Recently, Shirakawa et al [32,33] reported a comparative study of the LPL activity and mass (concentration) in the preand post-heparin plasma, suggesting that the determination of the LPL concentration in the pre-heparin plasma may take the place of LPL activity and mass in the post-heparin plasma for clinical diagnostic purposes. This is also supported by other previous reports as well [34,35].…”

Lipoprotein lipase does not increase significantly in the postprandial plasma

“…Therefore, when the LPL activity is not sufficient to hydrolyze a large amount of CM or VLDL on endothelium, the RLP particle size becomes significantly increased along with the high RLP-TG/RLP-C ratio and less amount of LPL concentration. We reported that RLP particle size in type 2 diabetes and metabolic syndrome was significantly larger than in controls and was inversely correlated with the circulating LPL concentration, indicating the pro-atherogenic characteristics of remnants [41]. The delayed clearance of RLP in plasma may largely depend on the amount of LPL on RLP, which is the ligand for the receptors of liver and other tissues and organs.…”

A new enzyme-linked immunosorbent assay system for human serum hepatic triglyceride lipase

“…LPL and EL concentrations were measured by ELISA as reported previously (12,14,15). HTGL activities were measured using the method reported previously (9, 10).…”