Plasma glutathione peroxidase activity as an index of renal function

Higher serum selenium concentration is associated with lower risk of all-cause and cardiovascular mortality among individuals with chronic kidney disease: A population-based cohort study of NHANES

Background

Selenium is an essential nutrient and trace element required for human health and plays an important role in antioxidative and anti-inflammatory processes. However, the long-term impact of selenium levels on the health of patients with chronic kidney disease remains unclear.

Method

Participants in this study were 3,063 CKD adults from the Third National Health and Nutrition Examination Survey (NHANES 1999–2000, 2003–2004, and 2011–2018). The mortality status and the cause of death of the study participants were obtained from the National Death Index records. For all-cause and cardiovascular disease (CVD) mortality, the models employed to estimate hazard ratios (HRs) and 95% CI were Cox proportional hazard models and competing risk models, respectively.

Result

During the follow-up period, 884 deaths occurred, including 336 heart-disease-associated deaths. The median (IQR) concentration of serum selenium was 181.7 (156.1, 201.5) μg/L. After full adjustment, serum selenium levels were associated with a decreased risk of mortality in patients with CKD, including all-cause and CVD mortality (P < 0.001). The multivariate-adjusted HRs (95%CI) were 0.684 (0.549–0.852) for all-cause mortality (Ptrend < 0.001) and 0.513 (0.356–0.739) for CVD mortality (Ptrend < 0.001) when selenium concentrations were compared according to the extreme quartiles. Selenium levels are inversely associated with an increased risk of all-cause mortality and CVD mortality. Similar results were observed in subgroup and sensitivity analyses.

Conclusion

Higher serum selenium concentration was independently associated with a decreased risk of all-cause and CVD mortality in patients with CKD.

Anti-proliferative, apoptotic potential of synthesized selenium nanoparticles against breast cancer cell line (MCF7)

Nano-biotechnology has grown rapidly and become an integral part of modern disease diagnosis and treatment. The aim of this survey was to evaluate the anticancer activity of synthesized selenium nanoparticles (Se-NPs) against breast cancer cells (MCF-7). The prepared Se-NPs were examined by ultraviolet-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), and energy dispersive spectroscopy (EDX). Antioxidant activity of Se-NPs property was studied by radical scavenging (DPPH) assay. The in-vitro cytotoxicity of Se-NPs was evaluated by MTT assay. In addition; the biological assessment (antioxidant and cytotoxicity) of synthesized Se-NPs was examined via molecular docking simulations. Synthesis of Se-NPs was characterized by several studies such as UV-absorbance, showing peak values in the range of 268 nm. Nanoparticle sizes of the nanoparticles are confirmed by dynamic light scattering analysis, indicating that average size is about 203 nm. The quantity of selenium in Se-NPs is 90.15% by weight, as confirmed by EDX. Synthesized Se-NPs have anti-proliferative effects on MCF-7 cell lines. Cytotoxicity and apoptotic potential assays exhibited a dose-dependent effect against MCF-7 cells using an MTT assay. Like anti-cancer activity, anti-oxidant activity of Se-NPs was dose-dependent. Findings showed that the Se-NPs complexes have the highest inhibitory effect against cytotoxic and antioxidant receptors. Results of this study demonstrated that Se-NPs had strong potential to scavenge free radicals and are cytotoxic against the MCF-7 cancer cell line.

Selenium supplementation in the form of selenium nanoparticles and selenite sodium improves mature male mice reproductive performances

OBJECTIVES

The current study was conducted to examine the possible protective and retentive effects of one-week intra-peritoneal (IP) administration of selenium nanoparticles (Se-NPs), compared to its bulk counterpart, selenite sodium (Ss), after one complete cycle of spermatogenesis in mature male mice.

MATERIALS AND METHODS

Thirty adult male mice were divided into 3 groups. Control group was administrated phosphate-buffered saline (IP) and the other groups received Ss (0.50 mg kg-1) and Se-NPs (0.50 mg kg-1) for seven successive days. Then, the animals were monitored for 28 days and finally sacrificed and tissue and blood samples were taken. Histopathological features, sperm quality, in vitro fertilization (IVF) capability and selenium (Se) content in testicular tissue were analyzed. Antioxidant enzyme activities including catalase, glutathione peroxidase, and superoxide dismutase as well as total antioxidant capacity and malondialdehyde levels were assessed in blood and the tissue samples.

RESULTS

Remarkable differences were found in sperm characteristics, histopathological features and oxidative stress biomarkers between control and treatment groups. Moreover, IVF evaluation and tissue Se concentration examination weren't similar for Se-NPs and Ss.

CONCLUSION

Conclusively, Se-treated groups had more antioxidant capacity than the control group, but sperm quality and histopathological features revealed that Se-NPs might possess more antioxidative and retentive potential compared to Ss in one spermatogenesis cycle.

Systemic Redox Imbalance in Chronic Kidney Disease: A Systematic Review

Patients with chronic kidney disease (CKD) experience imbalance between oxygen reactive species (ROS) production and antioxidant defenses leading to cell and tissue damage. However, it remains unclear at which stage of renal insufficiency the redox imbalance becomes more profound. The aim of this systematic review was to provide an update on recent advances in our understanding of how the redox status changes in the progression of renal disease from predialysis stages 1 to 4 to end stage 5 and whether the various treatments and dialysis modalities influence the redox balance. A systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. In total, thirty-nine studies met the inclusion criteria and were reviewed. Even from an early stage, imbalance in redox status is evident and as the kidney function worsens it becomes more profound. Hemodialysis therapy per se seems to negatively influence the redox status by the elevation of lipid peroxidation markers, protein carbonylation, and impairing erythrocyte antioxidant defense. However, other dialysis modalities do not so far appear to confer advantages. Supplementation with antioxidants might assist and should be considered as an early intervention to halt premature atherogenesis development at an early stage of CKD.

A kidney-specific genome-scale metabolic network model for analyzing focal segmental glomerulosclerosis

Focal Segmental Glomerulosclerosis (FSGS) is a type of nephrotic syndrome which accounts for 20 and 40 % of such cases in children and adults, respectively. The high prevalence of FSGS makes it the most common primary glomerular disorder causing end-stage renal disease. Although the pathogenesis of this disorder has been widely investigated, the exact mechanism underlying this disease is still to be discovered. Current therapies seek to stop the progression of FSGS and often fail to cure the patients since progression to end-stage renal failure is usually inevitable. In the present work, we use a kidney-specific metabolic network model to study FSGS. The model was obtained by merging two previously published kidney-specific metabolic network models. The validity of the new model was checked by comparing the inactivating reaction genes identified in silico to the list of kidney disease implicated genes. To model the disease state, we used a complete list of FSGS metabolic biomarkers extracted from transcriptome and proteome profiling of patients as well as genetic deficiencies known to cause FSGS. We observed that some specific pathways including chondroitin sulfate degradation, eicosanoid metabolism, keratan sulfate biosynthesis, vitamin B6 metabolism, and amino acid metabolism tend to show variations in FSGS model compared to healthy kidney. Furthermore, we computationally searched for the potential drug targets that can revert the diseased metabolic state to the healthy state. Interestingly, only one drug target, N-acetylgalactosaminidase, was found whose inhibition could alter cellular metabolism towards healthy state.

Plasma and erythrocyte glutathione peroxidase activity, serum selenium concentration, and plasma total antioxidant capacity in cats with IRIS stages I-IV chronic kidney disease

Background

Serum selenium concentrations and the activity of plasma glutathione peroxidase (GPx) decrease with the progression of chronic kidney disease (CKD) in human patients. Selenium is considered a limiting factor for plasma GPx synthesis. Plasma total antioxidant capacity (TAC) is decreased in CKD cats in comparison to healthy cats.

Hypothesis

Serum selenium concentrations and plasma and erythrocyte GPx activity in cats with CKD are lower than in healthy cats. Serum selenium concentrations, the activity of enzymes, and plasma TAC progressively decrease with the progression of kidney disease according to IRIS (International Renal Interest Society) classification.

Animals

Twenty‐six client‐owned cats in IRIS stages I–IV of CKD were compared with 19 client‐owned healthy cats.

Methods

A CBC, serum biochemical profile, urinalysis, plasma and erythrocyte GPx activity, serum selenium concentration, and plasma TAC were measured in each cat.

Results

Cats in IRIS stage IV CKD had a significantly higher (P = .025) activity of plasma GPx (23.44 ± 6.28 U/mL) than cats in the control group (17.51 ± 3.75 U/mL). There were no significant differences in erythrocyte GPx, serum selenium concentration, and plasma TAC, either among IRIS stages I–IV CKD cats or between CKD cats and healthy cats.

Conclusions and Clinical Importance

Erythrocyte GPx activity, serum selenium concentration, and plasma TAC do not change in CKD cats compared with healthy cats. Selenium is not a limiting factor in feline CKD. Increased plasma GPx activity in cats with stage IV CKD suggests induction of antioxidant defense mechanisms. Antioxidant defense systems might not be exhausted in CKD in cats.