Objective: To study the relationships between paraoxonase 1 55 Met/Leu (PON1 55Met/Leu), paraoxonase 2 148 Ala/Gly(PON2 148Ala/Gly) genetic polymorphisms and coronary artery disease(CAD), plasma activities of paraoxonase (PON), total superoxide dismutase (T-SOD), as well as plasma concentration of maleic dialdehyde (MDA).
Methods: The PCR-RFLP method was applied to identify the genetic polymorphisms of PON1 55Met/Leu and PON2 148Ala/Gly, and the colorimetry way was used to detect plasma activities of PON, T-SOD and plasma MDA concentration of 262 CAD patients and 100 controls.
Results: Comparing with control, the CAD patient had the obviously lower activities of enzymes PON (349.27+/- 138.36 nmol/min.mL vs 454.75+/- 166.00 nmol/min.mL, P< 0.001) and T-SOD (23.61+/- 16.51 U/mL vs 44.01+/- 22.68 U/mL, P< 0.001) while getting the plasma MDA concentration increased markedly(2.47+/- 0.73 nmol/mL vs2.15+/- 0.55 nmol/mL, P< 0.01). The CAD patient had more LM genotype and M allele of PON1 55Met/Leu(24.8% vs 1.4%, P< 0.001 and 12.4% vs 0.5%, P was 0.001 respectively), GG and AG genotype and G allele of PON2 148 Ala/Gly(11.8% vs 5.0%, P< 0.001; 48.1% vs 24.0%, P< 0.001 and 36.0% vs 17.0%, P< 0.001 respectively) than control did. The activities of plasma PON and T-SOD were lower in individuals with PON??1 55 LM genotype than those with LL genotype(304.73+/- 125.04 vs 394.84+/- 154.87 nmol/min.mL and 24.89+/- 16.14 vs 30.22+/- 21.29 U/mL, P< 0.001 and P< 0.05 respectively). The activity of plasma PON was also lower in individuals with PON2 148 GG/AG genotype than that with AA genotype(281.47+/- 84.70 vs 356.00+/- 145.95 vs 417.34+/- 159.00 nmol/min.mL, P< 0.001). Logistic regression analysis showed that PON1 55 LM genotype (OR 29.08, 95%CI 2.88-294.04, P was 0.004) and M allele(OR 15.17, 95%CI 1.32-174.29, P was 0.029), PON2 148 GG/AG genotype (OR 2.32, 95%CI 1.52-3.54, P< 0. 001) and G allele (OR 3.24, 95%CI 1.38-7.61, P was 0.007) were independent risk factors for CAD.
Conclusion: The CAD patient has the obviously low activities of plasma PON and T-SOD but on the contrary, get the plasma MDA concentration increased markedly. PON1 55 LM genotype and M allele, PON2 148 GG/AG genotype and G allele are the risk factors for coronary artery disease, and the activity of plasma PON is also markedly reduced in individuals with above genotypes.