The Interaction Between Selenium Status, Sex Hormones, and Thyroid Metabolism in Adolescent Girls in the Luteal Phase of their Menstrual Cycle

The objective of the present work was to study all physiological relationships among selenium status (SeS), sex hormones secretion (SH), and thyroid metabolism (ThM) in healthy adolescent girls, at one time. Forty-four girls aged 13.4–16.6 years (mean age, 14.5 ± 0.5 years) entered the statistical model. Parameters reflecting SeS: plasma selenium concentration (Se) and plasma glutathione peroxidase activity (GPX3); SH: serum estradiol (E₂) and progesterone (P₄); age of menarche (AoM); and ThM: thyroid stimulating hormone (TSH), free thyroxine (fT4), free triiodothyronine (fT3), antithyroid peroxidase antibodies (anti-TPO) in serum, and thyroid volume (ThV), were determined, and the interactions between them were evaluated by means of the partial least squares method (PLS). PLS method was, for the first time, successfully applied to the problem of selenium and hormone interactions and revealed that selenium status and female reproductive system are interrelated and affect thyroid physiology in adolescent girls in the luteal phase. The strongest associations were revealed for the pairs of parameters, Se and fT4/fT3, Se and P₄, the modest ones for the pairs, Se and ThV, P₄ and fT4/fT3, Se and AoM, and P₄ and AoM. There was no correlation between E₂, GPX3, and TSH, and any other considered parameter. Se and P₄ had the greatest influence on ThM parameters.     

Selenoproteins in human thyroid tissues

The aim of the present work was to clarify whether the activities of selenoenzymes can serve as markers for different tumors or goiters, as classified by histological criteria. The following parameters were determined: 1) selenium content of plasma (Se), 2) activities of the selenoenzymes: plasma glutathione peroxidase (plGSHPx), cytosolic glutathione peroxidase (cGSHPx), type I and type II iodothyronine deiodinases (ID-I, ID-II), thioredoxin reductase (THRR) in human thyroid tissues. The material came from follicular neoplasm, papillary carcinoma, struma nodosa, struma lymphomatosis Hashimoto, other thyroid surgery specimens, and normal tissues. There was no difference in Se nor in plGSHPx between patients and healthy volunteers. No significant differences were found for any parameter in thyroid carcinoma versus normal or goitrous thyroid tissue. In the whole group of thyroid surgery specimens the statistically significant correlations were found between ID-I and ID-II and between THRR and selenoperoxidases. Principal components analysis confirmed the above correlation and moreover revealed correlation between Se and plGSHPx, but did not detect any clear distinction between patients with the different diagnoses.     

DNA methylation status of the methylenetetrahydrofolate reductase gene promoter in peripheral blood of end-stage renal disease patients

End-stage renal disease (ESRD) is one of the main causes of morbidity and mortality worldwide. DNA methylation is a major epigenetic modification of the genome that has the potential to silence gene expression. Methylenetetrahydrofolate reductase (MTHFR) gene inactivation was recognized as a predisposing factor of hyperhomocysteinemia in renal patients. The current study aimed to determine the methylation status within the MTHFR promoter region in DNA isolated from peripheral blood of ESRD patients and controls and the correlation of this methylation with the clinical and biochemical characteristics in ESRD patients. Ninety-six ESRD patients and 96 healthy ethnically, age and gender matched controls were included within the study. MTHFR promoter methylation was assessed using methylation specific polymerase chain reaction. The frequency of MTHFR methylation was significantly higher in ESRD patients than in controls (P = 0.003), additionally, MTHFR methylation was associated to a decrease in estimated glomerular filtration rate, serum high-density lipoprotein cholesterol level and an increase in both serum total cholesterol and low-density lipoprotein cholesterol levels. Data generated from this study suggest the possible involvement of MTHFR promoter methylation in the pathogenesis of ESRD and support a new dimension of MTHFR inactivation.     

The effect of hemodialysis,peritoneal dialysis and renal transplantation on nutritional status and serum micronutrient levels in patients with end-stage renal disease; Multicenter, 6-month period,longitudinal study

PurposeNutritional status and micronutrient levels of end stage renal disease (ESRD) patients may vary depending on the mode of renal replacement therapy (RRT). We aimed to compare the effects of hemodialysis, peritoneal dialysis (PD) and renal transplantation (RT) on micronutrient levels and nutritional status in ESRD patients.Patients and MethodsA total of 77 ESRD patients who had not received RRT were included in this prospective longitudinal study. All ESRD patients underwent a blood serum analysis that assessed the micronutrients such as selenium, copper, zinc, chromium, retinol, thiamine and vitamin B6 as well as a nutritional status assessment. After the baseline assessments and the initiation of RRT was accomplished, all patients were followed for 6 months.ResultsThe study showed significant improvements in subjective global assessment scores (percentage increases in score A were 26.6 and 36.6; p = 0.039 and p = 0.001; respectively), mid-arm circumference and the skin-fold thicknesses (p < 0.001, p < 0.001; respectively) in the RT and hemodialysis groups. The examinations at sixth month revealed a significant increase in body weight (4.8 kg; p = 0.002) and albumin levels (0.6 g/dL; p < 0.001) in only RT group. Zinc, thiamin and vitamin B6 were the most deficient micronutrients (44.1 %, 24.7 % and 35.1 %; respectively) in ESRD patients. There was a significant increase in selenium and retinol levels (p = 0.020 and p < 0.001; respectively) but a significant decrease in thiamin levels (p = 0.041) in RT patients. A significant increase in retinol levels (p = 0.028) and a significant decrease in thiamin levels (p = 0.022) was observed in the hemodialysis patients. However, no significant change in micronutrient levels was observed in the PD patients.ConclusionThe results support the recommendation that ESRD patients should be supplemented with water-soluble vitamins, especially thiamine and vitamin B6, and trace elements, especially zinc. RT appears to be superior to other modes of RRT when examining SGA score, anthropometric measurements, albumin and micronutrient levels.     

Mechanisms of endothelial dysfunction in resistance arteries from patients with end-stage renal disease

The study focuses on the mechanisms of endothelial dysfunction in the uremic milieu. Subcutaneous resistance arteries from 35 end-stage renal disease (ESRD) patients and 28 matched controls were studied ex-vivo. Basal and receptor-dependent effects of endothelium-derived factors, expression of endothelial NO synthase (eNOS), prerequisites for myoendothelial gap junctions (MEGJ), and associations between endothelium-dependent responses and plasma levels of endothelial dysfunction markers were assessed. The contribution of endothelium-derived hyperpolarizing factor (EDHF) to endothelium-dependent relaxation was impaired in uremic arteries after stimulation with bradykinin, but not acetylcholine, reflecting the agonist-specific differences. Diminished vasodilator influences of the endothelium on basal tone and enhanced plasma levels of asymmetrical dimethyl L-arginine (ADMA) suggest impairment in NO-mediated regulation of uremic arteries. eNOS expression and contribution of MEGJs to EDHF type responses were unaltered. Plasma levels of ADMA were negatively associated with endothelium-dependent responses in uremic arteries. Preserved responses of smooth muscle to pinacidil and NO-donor indicate alterations within the endothelium and tolerance of vasodilator mechanisms to the uremic retention products at the level of smooth muscle. We conclude that both EDHF and NO pathways that control resistance artery tone are impaired in the uremic milieu. For the first time, we validate the alterations in EDHF type responses linked to kinin receptors in ESRD patients. The association between plasma ADMA concentrations and endothelial function in uremic resistance vasculature may have diagnostic and future therapeutic implications.     

Levels of selenium, zinc, copper, and antioxidant enzyme activity in patients with leukemia

Essential elements, mainly selenium and zinc, were involved in protection against oxidative stress in cells. Oxidation could lead to the formation of free radicals that have been implicated in the pathogenesis of many diseases, including leukemia. Leukemia is a neoplastic disease that is susceptible to antioxidant enzyme and essential elements alterations. This study was undertaken to examine the levels of essential elements, antioxidant enzymes activities, and their relationships with different types of leukemia. Serum selenium, zinc, and copper concentrations, red blood cell glutathione peroxidase (GPx) activities, plasma Cu−Zn superoxide dismutase (Cu−Zn SOD) activities and lipid peroxidation (LPO) levels were determined in 49 patients with different types of leukemia before initial treatment. Serum selenium and zinc concentrations were lower in leukemia patients than those of controls (p<0.01). Serum copper concentration was higher in leukemia patients than that of controls (p<0.01). The activities GPx and Cu−Zn SOD were significantly increased in leukemia patients, especially with acute leukemia (AL), acute lymphoid leukemia (ALL), and acute nonlymphoid leukemia (ANLL) (p<0.05), whereas no difference was found between those of chronic myelogeneous leukemia and the controls. The levels of LPO were normal as controls. Serum selenium concentration was not correlated with GPx, and serum levels of zinc and copper were not related to Cu−Zn SOD. Serum zinc levels had a negative correlation with the absolute peripheral blast cells, whereas serum copper had a positive correlation with the absolute peripheral blast cells. Increased GPx and Cu−Zn SOD activities and normal levels of LPO, which were a protective responses, were an indicator of mild oxidative stress; it mights indicate that the essentials elements alterations in leukemia patients were mostly dependent on tumor activity. Changes of their levels demonstrated that there are low selenium, zinc, and high copper status in leukemia patients. The decrease of plasma zinc and increase of the Cu/Zn ratio could be the index that showed an unfavorable prognosis of acute leukemia.     

Alteration of plasma total F2-isoprostanes before and after hemodialysis in end-stage renal disease patients

F(2)-isoprostanes are derived in vivo principally from the following: (1) the formation of positional peroxyl radicals of arachidonic acid, (2) endocyclization to prostaglandin G(2)-like structures, and (3) reduction to PGF(2)-like compounds. F(2)-isoprostanes have been proposed as biomarkers of lipid peroxidation, oxidative stress status, and the oxidation of low-density lipoprotein (LDL). Using gas chromatography-ion trap-mass spectrometry, we studied how hemodialysis (HD) affects plasma total F(2)-isoprostanes. We examined the plasma total F(2)-isoprostanes in end-stage renal disease (ESRD) patients, before HD, after HD, between HD, and in control subjects. Plasma concentrations of total F(2)-isoprostanes were significantly higher in the after HD ESRD patients than the before hemodialysis ESRD patients (P < 0.05). There is no difference between before HD ESRD patients and normal controls. Moreover, a positive or negative correlation was seen between LDL and plasma total F(2)-isoprostanes (P < 0.001), and between age and plasma total F(2)-isoprostanes (P < 0.001). This study indicates HD treatment may be the major contributor of oxidative stress in ESRD patients.     

Plasma and liver selenium levels in the rat during supplementation with 0.5, 2, 6, and 15 ppm selenium in drinking water

Plasma and liver selenium of Wistar rats were determined after 1, 3, and 6 mo supplementation with 0.5, 2, 6, or 15 ppm selenium as sodium selenite in drinking water. Plasma selenium was not different from control values at additional intake of 0.5 ppm but increased above usual levels at higher intakes. A highly significant correlation was observed between the total quantity of selenium ingested and plasma selenium after 1 mo treatment (r=0.99,p<0.01), but was less pronounced after 3 and 6 mo (0.94,p<0.05, and 0.78,p<0.05, respectively). The decrease in plasma selenium with time of treatment was more pronounced at higher intakes. There was also a highly significant correlation between total selenium intake and liver selenium concentration (r=0.99,p<0.01) after 1 mo of treatment, but this time liver selenium did not change with time, and the correlation remained highly significant throughout the investigation. Liver selenium therefore appears as a more sensitive and more representative measure of selenium intake than plasma selenium. Most supplements did not affect body weight and survival of animals, except when the diet was supplemented with 15 ppm for 6 mo; however, alterations in biochemical parameters concerning lipid status and hepatic function were observed at levels above 2.0 ppm.     

Large-scale mitochondrial DNA deletions in skeletal muscle of patients with end-stage renal disease

End-stage renal disease (ESRD) is associated with enhanced oxidative stress. This disease state provides a unique system for investigating the deleterious effect of exogenous sources of free radicals and reactive oxygen species (ROS) on mitochondrial DNA (mtDNA). To test the hypothesis that uremic milieu might cause more severe damage to mtDNA, we investigated the prevalence and abundance of mtDNA deletions in the skeletal muscles of ESRD patients. The results showed that the frequencies of occurrence of the 4977 bp and 7436 bp deletions of mtDNA in the muscle tissues of the older ESRD patients were higher than those of the younger patients. The frequency of occurrence of the 4977 bp-deleted mtDNA in the muscle was 33.3% for the patients in the age group of < 40 years, 66.6% in the 41-60-year-old group, 100% in the 61-80-year-old group, and 100% in patients >80 years of age, respectively. Only 22% of the normal aged controls carried the 4977 bp mtDNA deletion, whereas 77% (17/22) of the ESRD patients exhibited the mtDNA deletion. Using a semiquantitative PCR method, we determined the proportion of the 4977 bp-deleted mtDNA from the muscles that had been confirmed to harbor the deletion. We found that the proportions of the 4977 bp-deleted mtDNA in the muscle were significantly higher than those of the aged matched controls. Using long-range PCR techniques, a distinctive array of mtDNA deletions was demonstrated in the muscle of uremic patients. In summary, we found diverse and multiple mtDNA deletions in the skeletal muscles of ESRD patients. These deletions are more prevalent and abundant in ESRD patients than those found in normal populations. Accumulation of uremic toxins and impaired free radical scavenging systems may be responsible for the increased oxidative stress in ESRD patients. Such stress may result in oxidative damage and aging-associated mutation of the mitochondrial genome.     

Selenium status of idiopathic infertile Nigerian males

Selenium concentration in the sera and seminal plasma of 60 infertile males (40 oligospermia and 20 azoospermia) and 40 males with proven evidence of fertility (normospermia; control group) were estimated using atomic absorption spectrophotometry. Results were correlated with spermatogram and hormonal levels in order to determine their relationship and significance in male infertility. The mean serum concentrations of selenium was found to be significantly increased in oligospermic compared to azoospermic subjects and controls (p<0.01), whereas the seminal plasma level was significantly higher in azoospermic compared to oligospermic subjects and controls (p<0.001). Thus, the ratio of serum selenium to seminal plasma selenium was 1∶1 in controls, 4∶1 in oligospermia, and 1∶2 in azoospermic subject. A significant inverse correlation was observed between serum selenium level and sperm count (p<0.01). Similarly, seminal plasma selenium correlated with spermatozoa motility, viability, and morphology. Serum selenium level shows positive correlation with the serum testosterone level (p<0.01). In conclusion, there appears to be a physiological balance in the distribution of selenium in serum and seminal plasma compartment of control males. A disturbance in this balance has a significant influence on spermatogenesis. Selenium appears to have a positive influence on Leydig cells, thus influencing the secretion of testosterone.     

Novel, objective, multivariate biomarkers composed of plasma amino acid profiles for the diagnosis and assessment of inflammatory bowel disease

Background

Inflammatory bowel disease (IBD) is a chronic intestinal disorder that is associated with a limited number of clinical biomarkers. In order to facilitate the diagnosis of IBD and assess its disease activity, we investigated the potential of novel multivariate indexes using statistical modeling of plasma amino acid concentrations (aminogram).

Methodology and Principal Findings

We measured fasting plasma aminograms in 387 IBD patients (Crohn''s disease (CD), n = 165; ulcerative colitis (UC), n = 222) and 210 healthy controls. Based on Fisher linear classifiers, multivariate indexes were developed from the aminogram in discovery samples (CD, n = 102; UC, n = 102; age and sex-matched healthy controls, n = 102) and internally validated. The indexes were used to discriminate between CD or UC patients and healthy controls, as well as between patients with active disease and those in remission. We assessed index performances using the area under the curve of the receiver operating characteristic (ROC AUC). We observed significant alterations to the plasma aminogram, including histidine and tryptophan. The multivariate indexes established from plasma aminograms were able to distinguish CD or UC patients from healthy controls with ROC AUCs of 0.940 (95% confidence interval (CI): 0.898–0.983) and 0.894 (95%CI: 0.853–0.935), respectively in validation samples (CD, n = 63; UC, n = 120; healthy controls, n = 108). In addition, other indexes appeared to be a measure of disease activity. These indexes distinguished active CD or UC patients from each remission patients with ROC AUCs of 0.894 (95%CI: 0.853–0.935) and 0.849 (95%CI: 0.770–0.928), and correlated with clinical disease activity indexes for CD (r_s = 0.592, 95%CI: 0.385–0.742, p<0.001) or UC (r_s = 0.598, 95%CI: 0.452–0.713, p<0.001), respectively.

Conclusions and Significance

In this study, we demonstrated that established multivariate indexes composed of plasma amino acid profiles can serve as novel, non-invasive, objective biomarkers for the diagnosis and monitoring of IBD, providing us with new insights into the pathophysiology of the disease.     

Serum level of antioxidant vitamins and minerals in patients with vitiligo,a systematic review and meta-analysis

BackgroundAntioxidant status is considered as important factor in the pathogenesis of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. The purpose of this study was to systematically review the evidences comparing the serum levels of antioxidant vitamins and minerals between vitiligo patients and controls, and performing meta-analysis of the results.MethodsA comprehensive search was performed for studies comparing the serum status of antioxidant vitamins and minerals using following databases since inception up to 30 April 2020; PubMed, EMBASE, Scopus, and Web of Science. Data extraction was done by two independent reviewers. The data was pooled for serum level of each antioxidant comparing between vitiligo and control groups.ResultsThirteen studies were included in this systematic review. The serum level of vitamin A, C, E, selenium, zinc and copper were compared between vitiligo patients and controls in these studies. Eleven studies including 570 vitiligo cases and 580 controls were included in the meta-analysis. Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis. Based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C (OR = 1.17, 95 % CI, 0.74–1.84, P = 0.495), and vitamin E (OR = 0.61, 95 % CI, 0.30–1.25, P = 0.180). Higher serum zinc can decrease the risk of vitiligo based on sensitivity analysis of the results. (OR = 0.29, 95 % CI 0.15−0.54, P < 0.001). Higher serum selenium level significantly increased the risk of vitiligo (OR = 4.31, 95 % CI, 2.72–6.81, P < 0.001). Vitamin A was not significantly different in two reported groups (6.35 ± 1.53 vs 6.77 ± 1.46 μg/mL, P > 0.05). Copper was significantly higher in vitiligo patients compared to controls (129 ± 33 vs 99 ± 19 μg /100 mL, P = 0.002).ConclusionThe current meta-analysis of data on serum level of most studied antioxidants (vitamin C, vitamin E, zinc and selenium) in patients suffering vitiligo showed that higher serum selenium (OR = 4.31) and lower zinc level (OR = 0.29) can increased the risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies.     

Protective efficacy of ellagic acid on glycoproteins, hematological parameters, biochemical changes, and electrolytes in myocardial infarcted rats

The cardioprotective property of ellagic acid in rats has been reported previously. The present study reveals the protective role of ellagic acid in biochemical parameters including serum iron, plasma iron binding capacity, uric acid, glycoprotein, and electrolytes along with hematological parameters. Rats were subcutaneously injected with isoproterenol (ISO) (100 mg/kg) for 2 days to induce myocardial infarction. ISO-induced rats showed a significant increase in their levels of serum iron, serum uric acid, and blood glucose, and a significant decrease in their levels of plasma iron binding capacity, serum total protein, albumin/globulin ratio, and heart glycogen, when compared with normal control rats. The altered hematological parameters were also observed in ISO-induced rats when compared with normal control rats. Pretreatment with ellagic acid at doses of 7.5 and 15 mg/kg produced significant beneficial effect by returning all the above-mentioned biochemical and hematological parameters to near normal levels.     

Serum selenium,glutathione peroxidase,lipids, and human liver microsomal enzyme activity

This study evaluated selenium status in relation to lipid peroxidation, liver microsomal function, and serum lipids in humans. Serum selenium concentration, glutathione peroxidase (GSH-Px) activity, liver microsomal enzyme activity, assessed by plasma antipyrine clearance (AP-CL) rate, and serum lipids were determined in 23 healthy subjects in a double-blind placebo-controlled trial of selenium supplementation. The low selenium concentration (74.0±14.2 μg/L, mean±SD) is attributable to the low selenium content of the diet. Subjects with the lowest selenium levels (n=11) had reduced serum GSH-Px activity, AP-CL rate, high-density lipoprotein cholesterol (HDL-C), and total cholesterol (T-C) as compared with subjects with higher selenium concentrations (n=12). Low AP-CL rates were associated with low HDL-C: T-C ratios. Selenium supplementation, 96 μg/d for 2 wk, increased serum selenium, GSH-Px activity, and the HDL-C: T-C ratio. The results suggest that a low serum selenium level is associated with a decrease in liver microsomal enzyme activity and serum HDL-C and T-C concentrations. Selenium supplementation in subjects with low serum selenium may favorably influence relations between serum lipoproteins connected with the development of atherosclerotic vascular disease.     

Environmental factors, health-related habits, and serum selenium levels in cancer patients and healthy controls

Previous studies conducted in Yugoslavia indicated that the concentration of selenium in soil, food items, and serum of the population is very low. The aim of the study was to investigate the possible relationship among environmental, health-related habits, nutrition, and selenium serum levels in cancer patients and the healthy population. The case-control study included a group of cancer patients and a matched group of healthy controls: 57 cancer patients and 41 healthy controls living in Stari Grad (an urban area of Belgrade), as well as 17 cancer patients and 13 healthy controls living in Barajevo (a rural community in the vicinity of Belgrade). The healthy controls were matched to cancer patients in sex and age; they were not blood related. The selenium serum levels were measured by atomic absorption spectrophotometry. Health-related habits and relevant dietary factors (“food frequency” method) that may influence the selenium serum levels were assessed by questionnaires. The differences in average values of selenium serum levels between the cancer patients and healthy controls were not significantly different, but both were below the lowest recorded in referential studies. A significant difference between the values obtained from urban and rural subgroups was noted. The most important factors that influenced the level of selenium included the residence place in the region with selenium deficiency (Barajevo), age, associated chronic diseases, and some dietary factors potentially related to the intake of selenium. The results obtained in this investigation pointed out that use of selenium supplementation in this area should be seriously considered. Deceased     

Determinants of premature atherosclerosis in children with end-stage renal disease

Cardiovascular disease is a major cause of morbidity and mortality in young adults with end-stage renal disease (ESRD), but its basis is still not well understood. We therefore evaluated the determinants of atherosclerosis in children with ESRD. A total of 37 children with ESRD (with 31 who had undergone transplantation) were examined and compared to a control group comprising 22 healthy children. The common carotid intima-media thickness (CIMT) was measured by ultrasound as a marker of preclinical atherosclerosis. The association of CIMT with anthropometrical data, blood pressure, plasma lipid levels, and other biochemical parameters potentially related to cardiovascular disease was evaluated. Children with ESRD had significantly higher CIMT, blood pressure, and levels of lipoprotein (a), urea, creatinine, ferritin, homocysteine, and serum uric acid as well as significantly lower values of apolipoprotein A. The atherogenic index of plasma (log(triglycerides/HDL cholesterol)) was also higher in patients with ESRD; however, this difference reached only borderline significance. In addition, a negative correlation was found between CIMT and serum albumin and bilirubin in the ESRD group, and this correlation was independent of age and body mass index. In the control group, a significant positive correlation was observed between CIMT and ferritin levels. Factors other than traditional cardiovascular properties, such as the anti-oxidative capacity of circulating blood, may be of importance during the early stages of atherosclerosis in children with end-stage renal disease.     

Fibrates but not statins increase plasma selenium in dyslipidemic aged patients – The EVA study

This secondary analysis of “Etude du Vieillissement Artériel” (EVA) study reports the effect of fibrates and statins on plasma selenium concentration and its 9-year change in free-living dyslipidemic elderly. Dyslipidemic patients were categorized in three sub-groups according to final low-density lipoprotein (LDL)-cholesterol level or hypolipidemic treatment: non-treated dyslipidemic (LDL-cholesterol >4.41 mmol/L, n=84); dyslipidemics who were treated exclusively by fibrates (n=47) or by statins (n=25) whatever their serum LDL-cholesterol concentration. The influence of lipid-lowering treatments on plasma selenium concentrations and its 9-year change was evaluated by analysis of variance (ANOVA) and multivariate linear regression models taking into account cardiovascular risk and changes in lipid-profile parameters. Multivariate linear regression indicated that the plasma selenium decline was associated with the longitudinal variation in LDL (β=?0.039±0.019, p=0.04) and high-density lipoprotein (HDL)-cholesterol concentrations (β=0.187±0.059, p=0.002) but not with triglycerides (β=?0.018±0.031, p=0.57). During the 9-year follow-up, similar plasma selenium declines were observed in all the sub-groups (p=0.33) despite plasma selenium levels being higher in fibrate users and lower in statin users (p=0.0004). The mechanisms underlying these data are not yet totally understood, but considering the risk of selenium deficiency in the elderly and its relationship with poor health status further clinical trial is needed to verify the proposed hypotheses.     

Selenium and glutathione levels, and glutathione peroxidase activities in blood components of uremic patients on hemodialysis supplemented with selenium and treated with erythropoietin

Patients with chronic renal failure (CRF) often have reduced concentrations of selenium (Se) and lowered activities of glutathione peroxidase (GSH-Px) in blood components. The kidney is a major source of plasma GSH-Px. We measured Se and glutathione levels in blood components and red cell and plasma GSH-Px activities in 58 uremic patients on regular (3 times a week) hemodialysis (HD). The dialyzed patients were divided in 4 subgroups and were supplemented for 3 months with: 1) placebo (bakers yeast), 2) erythropoietin (EPO; 3 times a week with 2,000 U after each HD session), 3) Se-rich yeast (300 μg 3 times a week after each HD), and 4) Se-rich yeast plus EPO in doses as above. The results were compared with those for 25 healthy subjects. The Se concentrations and GSH-Px activities in the blood components of dialyzed uremic patients were significantly lower compared with the control group. Treatment of the HD patients with placebo and EPO only did not change the parameters studied. The treatment with Se as well as with Se and EPO caused an increase in Se levels and red cell GSH-Px activity. Plasma GSH-Px activity, however, increased only slowly or did not change after treatment with Se and with Se plus EPO. In the group treated with Se plus EPO the element concentration in blood components was higher compared with the group supplemented with Se alone. The weak or absence of response in plasma GSH-Px activity to Se supply indicates that the impaired kidney of uremic HD patients has reduced possibilities to synthesize this enzyme.     

Idiopathic scoliosis and concentrations of zinc,copper, and selenium in blood plasma

The concentration of zinc, copper, selenium, albumin, and ceruloplasmin in blood plasma and the activity of superoxide dismutase and glutathione peroxidase in erythrocytes were determined in a set of patients with idiopathic scoliosis (n=51). A significant decrease of selenium concentration (0.50±0.16 μmol/L) was found when compared with a control group (0.69±0.07 μmol/L) (p<0.01). The same levels of significance were found out for selenium levels corrected for albumin content. In a group of patients with a curvature over 45° indicated for a surgical correction, the average plasma concentrations of selenium were significantly lower (p<0.05) in comparison with a group of patients with a curvature below 45° treated conservatively. The GSH-Px activity in erythrocytes was the same in both sets. In comparison with the controls, no significant differences were revealed in all of the other parameters. The detection of the decreased blood plasma concentration of selenium has suggested possible disturbance of well-proportioned distribution and of general optimal availability of selenium in the organism of patients with idiopathic scoliosis with likely effects on the process of synthesis and maturation of collagen affecting the axial skeleton stability.     

Valproic Acid Modulates Superoxide Dismutase,Uric Acid-Independent FRAP and Zinc in Blood of Adult Epileptic Patients

We aimed to evaluate changes in antioxidant status in blood during valproate (VPA) monotherapy of adult patients with epilepsy. Antioxidant enzymes [plasma superoxide dismutase (pSOD), erythrocyte superoxide dismutase (eSOD)] and non-enzymatic indices [concentration of trace elements in serum: selenium, copper, zinc (sZn) and uric acid (UA), as well as the ferric reducing ability of plasma (FRAP) and UA-independent FRAP (UAiFRAP)] were evaluated in 21 adult patients with epilepsy and 21 healthy controls. Significant differences between the study group and controls were found for pSOD (p = 0.002) and UAiFRAP (p = 0.003). pSOD was higher, whilst UAiFRAP was lower in patients compared to controls. The activity of eSOD was higher in patients treated with VPA for a longer period (7–14 years) in comparison to controls (p = 0.001) and patients with a short period of VPA treatment (p < 0.001). Patients with uncontrolled epilepsy exhibited higher sZn than seizure-free patients (p = 0.041). Standard diet and moderate use of alcohol and/or nicotine did not exert significant effects on redox balance. We conclude that the antioxidant status of epileptic patients is modified by valproate monotherapy. The frequency of seizures and duration of VPA therapy are associated with changes of oxidative/antioxidative balance. The most sensitive and relevant parameters for antioxidative defence mechanism are pSOD, UAiFRAP and sZn.