Paraoxonase lactonase activity, inflammation and antioxidant status in plasma of patients with type 1 diabetes mellitus

Abstract

Objectives: To investigate paraoxonase-1 (PON 1 ) lactonase activity, myeloperoxidase (MPO) activity (as a marker of inflammation) and antioxidant status in plasma of patients with type 1 diabetes mellitus. Methods: Whole blood and plasma samples were collected from patients with diabetes and healthy control subjects. PON 1 lactonase and MPO activities and total antioxidant capacity (TEAC) were determined in plasma. Glycosylated haemoglobin (HbA1c) was quantified in whole blood. Results: Plasma PON 1 lactonase and MPO activities were significantly higher and TEAC was significantly lower in patients with diabetes (n ¼ 18) compared with healthy control subjects (n ¼ 20). There were significant positive correlations between PON 1 lactonase activity and MPO activity and HbA1c level, and plasma MPO and HbA1c. There were significant negative correlations between PON 1 lactonase activity and TEAC, and MPO activity and TEAC. Conclusions: Increased lactonase activity may inefficiently compensate for the high level of chronic inflammation and low antioxidant capacity in the plasma of patients with type 1 diabetes mellitus.

Effect of Lipoic Acid on Serum Paraoxonase-1 and Paraoxonase-3 Protein Levels and Activities in Diabetic Rats

“…In this study, we found that serum paraoxonase, arylesterase and lactonase activities are decreased in STZ-induced diabetic rats. These findings are also in agreement with the previous experimental [11,14,15] and human [16][17][18] studies of diabetes mellitus. We also found that there was no significant difference between the decrease percent of these serum enzyme activities.…”

“…It has been shown that PON1 prevents the development of atherosclerosis by protecting LDL against to oxidation and reducing macrophage foam cell formation [10]. Serum PON1 protein levels and paraoxonase, arylesterase and lactonase activities have shown to be decreased in diabetes [11][12][13][14][15][16][17][18] and PON1 has reported to be a…”

Decreases in Paraoxonase-1 Activities Promote a Pro-inflammatory Effect of Lipids Peroxidation Products in Non-smoking and Smoking Patients with Acute Pancreatitis

“…It was evidenced by negative correlation of Castelli Index 1 with PON-1(L) activity showed in the groups of non-smoking and smoking AP patients. A decrease in PON-1 activities can be a result of HDL dissociation from PON-1 molecule, its oxidation and increase in lipid peroxidation products concentrations under oxidative stress conditions as reported in other papers 46,47. This thesis seems to be confirmed in our study by the strong correlations of PON-1 activities with HDL concentration and negative association of HDL and MDA concentrations in the groups of AP patients.…”

High-Density Lipoprotein Function and Dysfunction in Health and Disease

“…Despite being at increased risk of dyslipidaemia, patients with type 1 diabetes commonly demonstrate elevated—rather than reduced—levels of HDL-c. Multiple studies have reported the presence of multiple dysfunctional properties to these particles, however, including reduced cholesterol efflux capacity [93, 94], reduced PON-1 activity [95], increased MPO activity [96], and decreased levels of S1P [97]. These modifications appear to be independent of HbA1c [93], and may at least partially explain the increased risk of CVD in patients with the highest HDL-c levels [98].…”