Chronic kidney disease (CKD) is a worldwide public health problem. Patients with CKD have a number of disorders in the organism, and the presence of oxidative stress and systemic inflammation in these patients is the subject of numerous studies. Chronic inflammation joined with oxidative stress contributes to the development of numerous complications: accelerated atherosclerosis process and cardiovascular disease, emergence of Type 2 diabetes mellitus, development of malnutrition, anaemia, hyperparathyroidism, and so forth, affecting the prognosis and quality of life of patients with CKD. In this review we presented the potential role of the myeloperoxidase enzyme in the production of reactive/chlorinating intermediates and their role in oxidative damage to biomolecules in the body of patients with chronic kidney disease and end-stage renal disease. In addition, we discussed the role of modified lipoprotein particles under the influence of prooxidant MPO intermediates in the development of endothelial changes and cardiovascular complications in renal failure.

This study investigated the relationship between serum xanthine oxidase (XOD) activity and the occurrence of diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus (T2DM) patients. Serum XOD activity, ischemia-modified albumin (IMA), uric acid (UA), albumin, glycated hemoglobin (HbA1c), advanced glycation end products (AGE), total free thiols, atherogenic index of plasma (AIP), and body mass index (BMI) were measured in 80 T2DM patients (29 with and 51 without DPN), and 30 nondiabetic control subjects. Duration of diabetes, hypertension, medication, and microalbuminuria was recorded. Serum XOD activities in controls, non-DPN, and DPN were 5.7 ± 2.4 U/L, 20.3 ± 8.6 U/L, and 27.5 ± 10.6 U/L (p < 0.01), respectively. XOD activity was directly correlated to IMA, UA, BMI, HbA1c, and AGE, while inversely correlated to serum total free thiols. A multivariable logistic regression model, which included duration of diabetes, hypertension, AIP, HbA1c, UA, and XOD activity, revealed HbA1c [OR = 1.03 (1.00–1.05); p = 0.034] and XOD activity [OR = 1.07 (1.00–1.14); p = 0.036] as independent predictors of DPN. Serum XOD activity was well correlated to several other risk factors. These results indicate the role of XOD in the development of DPN among T2DM patients.

The role of xanthine oxidase (XOD) in patients undergoing chronic hemodialysis treatment (HD) is poorly understood. Geriatric nutritional risk index (GNRI) ≤ 90 could be linked with malnutrition-inflammation complex syndrome. This study measured XOD, myeloperoxidase (MPO), superoxide dismutase (SOD), lipid hydroperoxides, total free thiol groups, and advanced oxidation protein products (AOPP) in 50 HD patients before commencing (pre-HD) and immediately after completion of HD session (post-HD) and in 22 healthy controls. Pre-HD serum hydroperoxides, AOPP, XOD, and SOD were higher and total thiol groups were lower in patients than in controls (P < 0.05, resp.). Compared to baseline values, serum MPO activity was increased irrespective of GNRI status. Serum XOD activity was increasing during HD treatment in the group with GNRI ≤ 90 (P = 0.030) whilst decreasing in the group with GNRI > 90 (P = 0.002). In a multiple regression analysis, post-HD serum XOD activity was independently associated with GNRI ≤ 90 (β  ± SE: 0.398 ± 0.151; P = 0.012) and HD vintage (β  ± SE: −0.349 ± 0.139; P = 0.016). These results indicate that an upregulated XOD may be implicated in HD-induced oxidative injury contributing to accelerated protein damage in patients with GNRI ≤ 90.

No abstract

Purpose The impact of cataract maturity on the aqueous humor (AH) oxidant/antioxidant balance is largely controversial. This study was aimed at assessing the relationships between cataract maturity and AH lipid peroxidation markers and enzymatic antioxidants. Patients and methods The concentrations of conjugated dienes (CD), lipofuscin-like fluorescent end-products (LLF), soluble proteins, as well as the activities of superoxide dismutase (SOD) and catalase (CAT) were measured in AH samples from nondiabetic patients with either immature (n ¼ 15) or mature (n ¼ 15) cataract. Results In the overall AH sample, the mean values of CD, LLF, SOD, and CAT were 0.160±0.024 (OD 234 ), 166±27 RFU, 24.5±7.1 U/ml, and 31.9±3.9 pmol/ml, respectively. CD was positively correlated with SOD (r ¼ 0.647; Po0.001), CAT (r ¼ À 0.394; P ¼ 0.031), and LLF (r ¼ À 0.399; P ¼ 0.029). The LLF was negatively correlated with SOD (r ¼ À 0.461; P ¼ 0.010). In samples adjusted for confounding factors, differences between immature and mature cataract groups regarding SOD, CD, LLF, and total proteins were significant (Po0.05; for all variables). The multiple logistic regression analysis identified LLF (OR ¼ 4.08; P ¼ 0.038) and SOD (OR ¼ 4.99; P ¼ 0.031) as independent predictors of cataract maturity. Conclusions These results suggest that AH lipid peroxidation markers and antioxidants may significantly depend on the cataract maturity stage.