Serum Paraoxonase Levels and PON1(192) Polymorphism in Type 2 Diabetes Mellitus Patients

Abstract

Objective: Paraoxonase-1 (PON1) is an HDL-associated enzyme implicated in the pathogenesis of atherosclerosis by protecting lipoproteins against peroxidation. PON1 has two genetic polymorphisms both due to amino acid substitution, one involving glutamine and arginine at position 192 and the other leucineand methionine at position 55. Our study aimed to compare the effect of PON192 polymorphism and PON1 activity in patients with type 2 diabetes mellitus (T2DM) and non-diabetic controls. Material and Methods: 50 patients with T2DM and 30 non-diabetic controls were included in this study. The PON192 polymorphism was studied by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Paraoxonase activity was measured by spectrophotometric method. Results: The frequencies of the QQ, QR and RR genotypes were found as 36.5 and 14% in type 2 diabetes patients and 26.67, 46.66, 26.67% in control subjects, respectively. The paraoxonase activity was detected at lower levels in diabetics (102.0 ±38.9) than in control subjects (158.1±63.7). PON1192 RR homozygotes had significantly higher PON activity than QR and QQ genotypes among control and type 2 diabetes patients (p<0.005). Conclusion:In comparing the activities of three genotypes of the control and type 2 diabetic groups; all activities were found significantly lower in diabetics. In conclusion, we suggested that paraoxonase activities are affected by PON1 genetic variability in patients with type 2 diabetes mellitus and controls.

European versus Asian differences for the associations between paraoxonase‐1 genetic polymorphisms and susceptibility to type 2 diabetes mellitus

“…One of the reasons may be the small number of subjects in the control group. For example, the study of Elnoamany et al [45] included 40 control subjects and the MAF of PON1 Q192R was 0.213, while the study of Gokcen et al [47]. included 30 control subjects and the MAF of PON1 Q192R was 0.5.…”

Paraoxonase 1 Activity and its Polymorphism in Type 2 Diabetic Nephropathy

“…The literature reports many studies correlating paraoxonase polymorphism in DM patients. S. Araki et al observed that there was no association between the PON1 poly-morphism and DN (15), while Gokcen et al observed a significant association between the PON1 polymorphism and DM (16). As different studies present conflicting results there is a need for further research to study the effect of DN on serum PON1 status.…”