(i) to determine the extent of oxidative stress and DNA damage and repair using a panel of selected markers in patients with type 1 and type 2 diabetes mellitus (T1DM, T2DM), (ii) to find their possible relationships with diabetes compensation and duration, and finally (iii) to test for the effect of functional polymorphisms in the 8-oxoguanin DNA glycosylase (rs1052133), catalase (rs1001179) and superoxide dismutase (rs4880) genes on respective intermediate phenotypes.
Catalase (CAT) is a major antioxidant enzyme and a number of polymorphisms in CAT have been shown to be associated with several diseases, including hypertension, diabetes mellitus, Alzheimer's disease, and vitiligo.
ASE reduced oxidative damage markers (TBARS, carbonyl levels and 8-isoprostane) in D and DH associated with a decrease in Nox 4 and p47 subunit expression and increase in antioxidant enzyme activity in both groups (SOD, catalase and GPx).
Cardiac levels of GSH were increased in Smoking groups whereas activities of catalase and superoxide dismutase increased in DM, Smoking and DM + Smoking groups.
Catalase (CAT) is a major antioxidant enzyme and a number of polymorphisms in the CAT have been described as being associated with several diseases, such as hypertension, diabetes mellitus, Alzheimer's disease, and vitiligo.
Decrease in Sirtuin1 (SIRT1) and nuclear factor erythroid 2-related factor (Nrf2) and increase in nuclear factor kappa B (NFκB) gene expression in diabetes were associated with a decrease in CAT and GPx mRNA expression.
Functionally, the antioxidants effect of NG is primarily attributed by reducing the free radical like reactive oxygen species (ROS) and enhancing the antioxidants activity such as superoxide dismutase (SOD), catalase, glutathione (GSH) in chronic diseases such as cardiovascular, neurodegenerative, diabetes, pulmonary, cancer and nephropathy.
Furthermore, the antioxidant enzyme activities of glutathione peroxidase and catalase in liver were increased and malondialdehyde level was decreased with AESA treatment compared with those in the DM group.
In patients with impaired glucose regulation and diabetes, the number of coronary artery branches with stenosis and the Gensini scores were inversely correlated with the plasma levels of CAT, SOD, GSH, GH, and GSH-Px (P < 0.001).
In the course of diabetes and insulin resistance, an intensified defensive activity of cells against the oxidative stress was observed in the undamaged skin, expressed by an increase in the relative content of superoxide dismutase 2 and 3, catalase and the activity of N-acetyl-β-d-hexosaminidase and β-d-glucuronidase.
Induction of diabetes was associated with a marked reduction in glutathione (GSH) levels; decreased activities of GSH peroxidase (GSH Px), manganese superoxide dismutase (MnSOD) and catalase; increased reactive oxygen species (ROS) levels and iNOS activity in plasma and lymphoid organs.
L. rhamnosus NCDC 17 improved oral glucose tolerance test, biochemical parameters (fasting blood glucose, plasma insulin, glycosylated haemoglobin, free fatty acids, triglycerides, total cholesterol, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol), oxidative stress (thiobarbituric acid reactive substance and activities of catalase, superoxide dismutase and glutathione peroxidase in blood and liver), bifidobacteria and lactobacilli in cecum, expression of glucagon like peptide-1 producing genes in cecum, and adiponection in epididymal fat, while decreased propionate proportions (%) in caecum, and expression of tumour necrosis factor-α and interlukin-6 in epididymal fat of diabetic rats as compared to diabetes control group.
Levels of superoxide dismutase and catalase were both reduced and hydrogen peroxide was increased in vehicle-treated DM, but these changes were reversed by fenofibrate treatment.
Liver TBARS and GST increased, while AST, ALT, LDH, ALP, ACP, catalase activity (CAT) and SOD decreased in the CIH, DM and CIH‑DM groups, compared with the control group.
Plasma and cardiac levels of total nitrite, endothelin -1 (ET-1), and myeloperoxidase (MPO) increased in the DM group, whereas cardiac activities of catalase and superoxide dismutase (SOD) decreased.
Rats were studied 30 days after the STZ treatment, and the diabetes untreated model group presented significantly higher kidney index, blood glucose, triglyceride (TG), total cholesterol (TC), malondialdehyde (MDA), interferon-γ (IFN-γ), and IFN-γ/IL-4 levels, lower body weight, fasting blood insulin (FPI), IL-4, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and nitric oxide (NO) levels and worse renal function (higher blood urea nitrogen (BUN), serum creatinine (SCr), urine protein (UP) levels and glomerular extracellular matrix (relative area)) compared with the normal control group (p < 0.05).