Evaluation of Paraoxonase-۱ Activity of Arylesterase and Lactonase and Their Correlation with Oxidative Stress in Children with Type ۱ Diabetes Mellitus

Background: Type ۱ diabetes mellitus (T۱DM) is a chronic autoimmune condition that can lead to long-term complications due to oxidative stress and metabolic dysregulation. Paraoxonase-۱ (PON-۱), an enzyme associated with high-density lipoprotein (HDL), has dual activities: arylesterase and lactonase. These activities protect lipids from oxidative damage. The functional status of PON-۱ in children with T۱DM may provide insights into the relationship between oxidative stress and the enzyme’s protective role. This study aims to assess the arylesterase and lactonase activities of PON-۱ in Iraqi children with T۱DM. Methods: Sixty-seven children with T۱DM were enrolled and compared with ۵۷ age-matched healthy controls. The enzymatic activities of arylesterase and lactonase were measured to evaluate PON-۱’s functional status. The Paraoxonase-۱/HDL (PON/HDL) ratio was calculated to assess lipid protection and antioxidant capacity. Oxidative status was assessed by measuring total oxidative status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI). Results: PON-۱ activity analysis showed a significant reduction in arylesterase (۲.۳۶ ± ۱.۱۷) and lactonase (۲۱.۹ ± ۷.۳۱) in the patients group compared to controls (arylesterase=۴.۵۴ ± ۱.۸۴, lactonase =۲۹.۵۱ ± ۹.۹۲). TOS and OSI were significantly higher, while TAS was significantly lower in the patients group. Pearson correlation revealed a positive correlation between HDL-C and arylesterase (P = ۰.۰۰۲, r = ۰.۳۷۹), and HDL-C and lactonase (P = ۰.۰۴۰, r = ۰.۳۶۶). Conclusion: Reduced PON-۱ activity is associated with T۱DM, suggesting that enhancing PON-۱ or reducing oxidative stress may help prevent diabetic complications and improve cardiovascular health.

کلیدواژه ها:

Antioxidant Activity ، Paraoxonase-۱ ، Arylesterase ، lactonase ، Oxidative Damage ، Type I Diabetes Mellitus.