Paraoxonase 1 Phenotype and Mass in South Asian versus Caucasian Renal Transplant Recipients

Abstract EN

South Asian renal transplant recipients have a higher incidence of cardiovascular disease compared with Caucasian renal transplant recipients.

We carried out a study to determine whether paraoxonase 1, a novel biomarker for cardiovascular risk, was decreased in South Asian compared with Caucasian renal transplant recipients.

Subjects were matched two to one on the basis of age and sex for a total of 129 subjects.

Paraoxonase 1 was measured by mass, arylesterase activity, and two-substrate phenotype assay.

Comparisons were made by using a matched design.

The frequency of PON1 QQ, QR and RR phenotype was 56%, 37%, and 7% for Caucasian subjects versus 35%, 44%, and 21% for South Asian subjects (χ2=7.72, P=0.02).

PON1 mass and arylesterase activity were not significantly different between South Asian and Caucasian subjects.

PON1 mass was significantly associated with PON1 phenotype (P=0.0001), HDL cholesterol (P=0.009), LDL cholesterol (P=0.02), and diabetes status (P<0.05).

Arylesterase activity was only associated with HDL cholesterol (P=0.003).

Thus the frequency of the PON1 RR phenotype was higher and that of the QQ phenotype was lower in South Asian versus Caucasian renal transplant recipients.

However, ethnicity was not a significant factor as a determinant of PON1 mass or arylesterase activity, with or without analysis including PON1 phenotype.

The two-substrate method for determining PON1 phenotype may be of value for future studies of cardiovascular complications in renal transplant recipients.