To: Walter U, Toepfer T, Dittmar KE et al. (2003) Pancreatic NOD beta cells express MHC class II protein and the frequency of I-A(g7) mRNA-expressing beta cells strongly increases during progression to autoimmune diabetes. Diabetologia 46:1106-1114

Prothrombogenic factors and reduced antioxidative defense in children and adolescents with pre-metabolic and metabolic syndrome

BACKGROUND

The aim of this study was to examine prothrombogenic factors and antioxidative defense in obese children and adolescents with pre-metabolic and metabolic syndrome, and to analyze insulin secretion and resistance, early glycoregulation disorders and lipid status.

METHODS

Insulin sensitivity was determined using the homeostasis model assessment for insulin resistance (HOMA-IR), while insulin secretion was determined using the homeostasis model assessment beta (HOMA-beta). Prothrombogenic factors analyzed were plasma plasminogen activator inhibitor-1 (PAI-1) and fibrinogen. Superoxide dismutase and glutathione peroxidase were measured as markers of antioxidative defense.

RESULTS

Patients with metabolic syndrome were characterized with increased body mass index (BMI), waist circumference, and HOMA-IR and HOMA-beta levels, and all had increased blood pressure and triglyceride levels, low high-density lipoprotein cholesterol levels, increased PAI-1 levels and reduced antioxidative defense levels. Patients with pre-metabolic syndrome had higher levels of basal and mean insulinemia during an oral glucose tolerance test, higher levels of HOMA-beta and lower levels of antioxidative defense compared to patients with metabolic syndrome.

CONCLUSIONS

Negative correlations between antioxidative defense parameters and BMI, abdominal obesity, insulin secretion, systolic blood pressure and atherogenic lipid factors, as well as correlations between PAI-1 and insulin resistance and basal glycemia in the metabolic syndrome group contribute to accelerated atherosclerosis. Positive correlations between PAI-1 and waist circumference and BMI, and negative correlations between BMI and antioxidative defense in the pre-metabolic syndrome patients show that this early stage preceding the metabolic syndrome is also characterized by atherosclerotic complication risks and evident hyperinsulinism and insulin resistance.

Parameters of antioxidative defense in type 2 diabetic patients with cardiovascular complications

OBJECTIVE

Diabetes-associated oxidative stress is a consequence of both increased production of free radicals and reduced capacity of antioxidative defense. Prolonged hyperglycemia is the major factor in the pathogenesis of atherosclerosis in diabetes which can lead to cardiovascular complications. The aim of this study was to test the parameters of antioxidative defense in type 2 diabetic patients.

METHODS

A total of 117 type 2 diabetics with and without cardiovascular complications were examined in order to find out the influence of hyperglycemia, type and duration of complications and duration of diabetes on the extent of disorder of antioxidative parameter values: superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and total antioxidant status (TAS).

RESULTS

Compared to healthy control subjects, type 2 diabetic patients with cardiovascular complications (CVC) had significantly lower SOD (P<0.0001), GSH-Px (P<0.0001), GR ( P = 0.0002) and TAS values (P<0.0001). In type 2 diabetic subjects with CVC, males had significantly lower SOD (778.7+/-103.2 U/gHb, P<0.01) and GR activities (52.2+/-8.9 U/L, P<0.001) compared to females (839.3+/-94.9 U/gHb; 58.5+/-9.1 U/L). Significant and positive correlation was found between glucose levels and SOD (r = 0.375 for P<0.05) and GSH-Px (r = 0.384, P<0.05 ) activity in the group of complications-free diabetics, while significant negative correlation between glucose and GSH-Px values (r = -0.382, P<0.05) was found in the group of type 2 diabetics with coronary artery disease (CAD) and hypertension (HTA) and with CAD and acute myocardial infarction (AMI) (r = -0.860 P<0.05), and highly negative correlation between glucose and SOD levels (r = -0.590, P<0.05) in the group of diabetic subjects with CAD, AMI and HTA. Likewise, there was highly significant negative correlation of SOD (r = -0.949, P<0.05) and TAS (r = -0.393 for P = 0.038) with duration of diabetes in the group of diabetics with CAD and HTA.

CONCLUSION

Our results confirm the hypothesis that there is reduced antioxidative defense in type 2 diabetics with prominent cardiovascular complications, which negatively correlates with glucose concentrations and duration of diabetes and cardiovascular complications.