High serum apolipoprotein AIV levels in renal transplant recipients

Background: Human apolipoprotein (apo) AIV might play a role in post-transp lant reverse cholesterol transport, which appears to be comparable to that seen in healthy subjects. However, there may be subtle differences between healthy individuals and renal transplant recipients, given the other abnorm alities of lipoprotein metabolism in the latter. Therefore, the aim of the present study was to investigate possible changes of serum apo AIV levels i n renal transplant recipients, and to evaluate potential factors influencin g these levels. Patients and methods: Total and free serum apo AIV was dete rmined in 36 clinically stable renal transplant recipients and in 20 sex- a nd age-matched healthy control subjects. Results: Mean total serum apo IV c oncentrations ( SD) were significantly higher in renal transplant recipient s than in control subjects (202 +/- 102 vs 79 +/- 45 mg/l, p < 0.01). The p ercentage of lipoprotein-free fractions of apo AIV was comparable in both g roups. The elevated total serum concentrations of apo AIV were mainly relat ed to creatinine clearance and partially to serum triglyceride levels in re nal transplant recipients. Conclusion: Our data suggest that the observed e levation of serum apo AIV concentrations in renal transplant recipients is essentially related to the presence of impaired renal function.