Investigation of the potential association of vitamin D binding protein with lipoproteins

Ann Clin Biochem. 2010 Mar;47(Pt 2):143-50. doi: 10.1258/acb.2009.009018. Epub 2010 Feb 9.


Background: Vitamin D binding protein (DBP) acts as a vitamin D carrier and an actin scavenger. We have previously reported a correlation between serum DBP and lipid parameters in a cystic fibrosis population. In the present study, the relationship between serum DBP, lipoprotein fractions and vitamin D is investigated.

Methods: The presence of DBP in lipoprotein fractions was examined using precipitation, gel permeation chromatography and ultracentrifugation. The association between DBP and lipids was investigated in a cohort study of 211 men. Total and actin-free DBP concentrations were assessed by immunonephelometry and enzyme-linked immunosorbent assay. Serum 25(OH)- and 1.25(OH)(2)-vitamin D(3) were assayed by radioimmunoassay. Total cholesterol, high-density lipoprotein cholesterol (HDL), triglycerides and insulin were measured using routine methods. Low-density lipoprotein-cholesterol (LDL) was calculated according to Friedewald's formula.

Results: DBP was found to be present in very-low-density lipoprotein (VLDL). Gel permeation chromatography revealed a bimodal DBP distribution with a lipid-bound fraction besides the known free fraction. Ultracentrifugation confirmed the presence of DBP and 25(OH)-vitamin D(3) in the VLDL particle. Total serum DBP concentration and the actin-bound DBP/DBP ratio correlated significantly with total cholesterol, LDL-cholesterol, triglycerides and albumin. The 25(OH)-vitamin D(3)/DBP ratio correlated negatively with serum triglyceride concentration and body mass index (BMI). The actin-bound DBP complex was identified with Western blot.

Conclusions: The lipid-bound DBP fraction may be of greater importance than initially thought. The present findings may have clinical consequences in view of the important physiological role of DBP.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Carrier Proteins / blood*
  • Cholesterol / blood
  • Cholesterol Esters
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Cholesterol, VLDL / blood
  • Enzyme-Linked Immunosorbent Assay / methods
  • Humans
  • Lipids / blood
  • Lipoproteins / blood*
  • Lipoproteins, LDL / blood
  • Lipoproteins, VLDL / blood
  • Male
  • Proteins / metabolism
  • Triglycerides / blood
  • Ultracentrifugation / methods
  • Vitamin D / blood*
  • Vitamin D / metabolism*
  • Vitamin D-Binding Protein / blood*


  • Carrier Proteins
  • Cholesterol Esters
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Cholesterol, VLDL
  • Lipids
  • Lipoproteins
  • Lipoproteins, LDL
  • Lipoproteins, VLDL
  • Proteins
  • Triglycerides
  • Vitamin D-Binding Protein
  • low density lipoprotein inhibitor
  • Vitamin D
  • Cholesterol