Active and low-active forms of serum phospholipid transfer protein in a normal Finnish population sample.
Human serum phospholipid transfer protein (PLTP) exists as a catalytically active (HA-PLTP) and a low-active (LA-PLTP) form. In this study, the association of PLTP activity and the concentrations of both forms with lipid and carbohydrate parameters were investigated. In a random Finnish population sample, serum PLTP concentration (n=250) was 6.56 +/- 1.45 mg/l, the mean lipoprotein-independent (PLTPexo) phospholipid transfer activity was 6.59 +/- 1.66 micromol/ml/h, and the mean lipoprotein-dependent (PLTPendo) activity was 1.37 +/- 0.29 micromol/ml/h. Of the serum PLTP concentration, approximately 46% was in a catalytically active form. HA-PLTP concentration correlated positively with serum PLTPexo activity (r=0.380, P <0.001), HDL cholesterol (r=0.291, P <0.001), and apolipoprotein A-I (r=0.187, P <0.01). Of the potential regulatory factors for PLTP, apolipoprotein E showed a weak positive correlation with serum PLTPexo (r=0.154, P <0.05) and PLTPendo (r=0.192, P <0.01) activity but not with PLTP concentration. Weak associations were also observed between PLTP parameters and determinants of glucose homeostasis (glucose, insulin, and homeostasis model assessment for insulin resistance). The present data on PLTP activity and concentration reveal novel connections of the two PLTP forms to lipid and carbohydrate metabolism.
Jänis
Minna T
MT
Department of Molecular Medicine, National Public Health Institute, Biomedicum, Helsinki, Finland.
Siggins
Sarah
S
Tahvanainen
Esa
E
Vikstedt
Riikka
R
Silander
Kaisa
K
Metso
Jari
J
Aromaa
Arpo
A
Taskinen
Marja-Riitta
MR
Olkkonen
Vesa M
VM
Jauhiainen
Matti
M
Ehnholm
Christian
C
D008076:Cholesterol, HDL / Q000378:metabolism; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008875:Middle Aged; D049294:Phospholipid Transfer Proteins / Q000737:chemistry* / Q000378:metabolism
D008076:Cholesterol, HDL; D008565:Membrane Proteins; D049294:Phospholipid Transfer Proteins