Oxidative stress, inflammation and early cardiovascular damage in children with chronic renal failure

Investigation of serum ischemic-modified albumin, galectin-3, paraoxonase-1, and myeloperoxidase activity levels in patients with acute brucellosis

OBJECTIVES

Infection remains current as an important discussion topic in the etiological factors of atherosclerosis. Ischemic-modified albumin (IMA), galectin-3 (gal-3), paraoxonase-1 (PON-1), and myeloperoxidase (MPO) are biomolecules that play an important role in the pathogenesis of atherosclerosis. Our aim is to investigate serum IMA, gal-3, PON-1, and MPO activity in acute brucellosis infection.

MATERIALS AND METHODS

Forty patients with acute brucellosis and 40 healthy individuals were included in the study. Serum IMA, gal-3, PON-1, and MPO activity were analyzed by the ELISA method.

RESULTS

In acute brucellosis infection, serum gal-3, IMA, and MPO activities were found to be significantly increased compared to the control group, and PON-1 activity was found to be significantly decreased compared to the control group (p < 0.001). There was a positive correlation between serum IMA, and MPO activity (r = 0.707 p = 0.000) and a negative correlation (r = -0.943, p = 0.000) between PON-1 activity. There was a positive correlation between serum gal-3 and MPO activity (r = 0.683, p = 0.000) and IMA level (r = 0.927, p = 0.000) and a negative correlation between PON-1 activity (r = -0.951, p = 0.000).Conclusion, it was found that serum gal-3, IMA levels and MPO activity increased, while PON-1 activity decreased. These results showed that the oxidant-anti-oxidant balance is impaired in acute brucellosis infection. In addition, these results indicate that brucella infection may be increase the risk of atherosclerosis. Further studies are needed to support our findings.

Gut microbiota modulation by plant polyphenols in koi carp (Cyprinus carpio L.)

Plant polyphenol supplementation may improve fish health in aquaculture systems. To assess the potential benefits and function mechanism of plant polyphenols in aquaculture, fish were fed either basal feed (CON) or the basal feed supplemented with 500 mg/kg of curcumin (CUR), oligomeric proanthocyanidins (OPC), chlorogenic acid (CGA), or resveratrol (RES). After an 8-week feeding experiment, blood samples were used to analyze the concentrations of biochemical indices. Gut samples were collected to evaluate microbiota, short chain fatty acid (SCFA) levels, and gene expression. The results indicated that polyphenol administration reduced serum glucose and insulin. Lysozyme activity was enhanced by OPC and CGA, and superoxide dismutase activity was increased by CUR, OPC, and CGA. The gut microbial structure of the RES group was segregated from that of the CON, and the genus Bacteroides was identified as a potential biomarker in the CUR, CGA, and RES groups. Total gut SCFA increased in the CUR, CGA, and RES groups. A strong correlation was observed between Bacteroides and SCFA. In conclusion, dietary polyphenols have distinct anti-inflammatory, anti-oxidant, and anti-hyperglycemic activities that may be closely associated with their microbiota-modulation effects.

Pediatric Mineral and Bone Disorder of Chronic Kidney Disease and Cardiovascular Disease

Chronic kidney disease is common and causes significant morbidity including shortened lifespans and decrease in quality of life for patients. The major cause of mortality in chronic kidney disease is cardiovascular disease. Cardiovascular disease within the chronic kidney disease population is closely tied with disordered calcium and phosphorus metabolism and driven in part by renal bone disease. The complex nature of renal, bone, and cardiovascular diseases was renamed as mineral and bone disorder of chronic kidney disease to encompass how bone disease drives vascular calcification and contributes to the development of long-term cardiovascular disease, and recent data suggest that managing bone disease well can augment and improve cardiovascular disease status. Pediatric nephrologists have additional obstacles in optimal mineral and bone disorder of chronic kidney disease management such as linear growth and skeletal maturation. In this article, we will discuss cardiovascular and bone diseases in chronic kidney disease and end-stage kidney disease patients with a focus on pediatric issues and concerns.

Systemic Inflammation, Oxidative Stress and Cardiovascular Health in Children and Adolescents: A Systematic Review

Recent studies indicate that cerebrovascular diseases and processes of atherosclerosis originate in the childhood era and are largely influenced by chronic inflammation. Some features of vascular dysfunction in adulthood may even be programmed prenatally via genetic influences and an unfavorable intrauterine milieu. Oxidative stress, defined by an imbalance between the production and generation of reactive oxygen species (ROS) in cells and tissues and the capability of an organism to scavenge these molecules via antioxidant mechanisms, has been linked to adverse cardiovascular health in adults, yet has not been systematically reviewed in the pediatric population. We performed a systematic search as per the PRISMA guidelines in PubMed/Medline and Cochrane Reviews and detected, in total, 1228 potentially eligible pediatric articles on systemic inflammation, oxidative stress, antioxidant use, cardiovascular disease and endothelial dysfunction. The abstracts and full-text manuscripts of these were screened for inclusion and exclusion criteria, and a total of 160 articles were included. The results indicate that systemic inflammation and oxidative stress influence cardiovascular health in many chronic pediatric conditions, including hypertension, obesity, diabetes mellitus types 1 and 2, chronic kidney disease, hyperlipidemia and obstructive sleep apnea. Exercise and diet may diminish ROS formation and enhance the total serum antioxidant capacity. Antioxidant supplementation may, in selected conditions, contribute to the diminution of the oxidative state and improve endothelial function; yet, in many areas, studies provide unsatisfactory results.

Effect of L-Carnitine Supplementation on Inflammatory Markers and Serum Glucose in Hemodialysis Children: A Randomized, Placebo-Controlled Clinical Trial

OBJECTIVES

Chronic inflammation is present in a high proportion of the chronic kidney disease (CKD) population, which can increase the risk of cardiovascular disease. Moreover, it is known as the leading cause of death in these patients. In addition, change in glucose metabolism is another common problem among CKD population. In this regard, it was found that insulin resistance and inflammation can perpetuate each other and simultaneously cause atherosclerosis. Because some studies have previously shown the positive effects of L-carnitine on reducing inflammation and controlling blood sugar, in the present study, we examined the effects of L-carnitine supplementation on serum inflammatory markers, fasting blood sugar (FBS), free carnitine (FC), albumin levels, and quality of life score among children on hemodialysis.

METHOD

Twenty-four children on hemodialysis (aged between 6 and 18 years) were enrolled in this randomized clinical trial study. Thereafter, 12 patients received 50 mg/kg of L-carnitine and 12 patients received placebo for a 10-week period. Afterward, we determined serum FC, interleukin-6 (IL-6), high-sensitivity C-reactive protein, FBS, and albumin and Pediatrics Quality of Life scores once at the baseline and once after performing intervention for 10 weeks. Moreover, the one-way repeated measures analysis was used to evaluate the effects of L-carnitine supplementation.

RESULTS

Although oral L-carnitine supplementation led to the decreased high-sensitivity C-reactive protein, this change was not significant compared with the placebo. Also, L-carnitine supplementation has significantly reduced serum levels of IL-6 and FBS, which has also raised serum FC and Pediatrics Quality of Life scores compared with the placebo. Notably, no significant change was observed in serum albumin levels.

CONCLUSION

Given the significant reductions in IL-6 and FBS levels, L-carnitine supplementation appeared to have some positive effects on the inflammation, blood glucose control, and prevention of cardiovascular events in these patients, as well as the improvement of quality of life. In this regard, L-carnitine therapy with a longer duration is recommended to obtain more effective results.

Oxidative stress accelerates the carotid atherosclerosis process in patients with chronic kidney disease

INTRODUCTION

The atherosclerosis process is highly accelerated in patients with chronic kidney disease (CKD). Oxidative stress is considered as one of the pro-atherogenic factors involved in accelerating the atherosclerosis process of the carotid artery. The aim of the present study was to determine the relationship between oxidative stress markers and the progression of carotid atherosclerosis in CKD patients.

MATERIAL AND METHODS

The study was conducted on 162 patients with CKD and 40 controls, and the disease stage was scored between 2 and 5D. Blood samples were taken and advanced oxidative protein product, myeloperoxidases, malondialdehyde, nitric oxide, glutathione, and oxidised low-density lipoprotein were measured. Furthermore, we studied the correlations between these biomarkers and clinical and para-clinical cardiovascular complications.

RESULTS

The average age of patients was 56.5 years. The oxidative stress markers average ± SD levels in CKD groups compared to the control were as follows: advanced oxidation protein product (61.89 ±1.4 vs. 26.65 ±1.05 µmol/l), myeloperoxidase (59.89 ±1.98 vs. 38.45 ±1.98 UI/ml), malondialdehyde (6.1 ±0.12 vs. 3.26 ±0.03 µmol/l), nitric oxide (65.82 ±1.06 vs. 52.19 ±2.1 µmol/l), glutathione (52.21 ±1.3 vs. 89.4 ±2.6 IU/ml), and oxLDL (15.57 ±1.07 vs. 1.72 ±0.82 µmol/l). While the glutathione level decreased significantly in advanced CKD stage (p < 0.05), the concentrations of all the other biomarkers increased significantly in accordance with CKD score (p < 0.05).

CONCLUSIONS

Cardiovascular diseases, mainly atherosclerosis, can be diagnosed indirectly by measuring oxidative stress markers. Furthermore, theses markers can be used to predict the progression of CKD, for better management of the disease.

Regenerative potential of platelets in patients with chronic kidney disease

INTRODUCTION

Chronic kidney disease (CKD) is a systemic disease affecting many organs. Progression of renal failure aggravates ongoing inflammation and increases oxidative stress. In the final stage of CKD, it is necessary to use renal replacement therapy. A side effect of dialysis therapy is the synthesis of proinflammatory factors and increased oxidative stress, which activates platelets and immune cells.

AIM OF THE STUDY

To determine the regenerative potential of platelets in patients with CKD based on the analysis of the relationships between substances with potential regenerative action, as well as analysis of the influence of the type of renal replacement therapy used on regeneration of platelets.

MATERIALS AND METHODS

The study group consisted of 117 patients. Based on the type of therapy used, patients were divided into four groups: hemodialysis, peritoneal dialysis, kidney transplant patients, and conservative treatment (30, 30, 27, and 30 patients). The control group consisted of 30 healthy volunteers. The concentrations of IGF-1, TGF-β, and PDGF-B in the blood serum were measured by ELISA methods.

RESULTS

It was shown that renal replacement therapy significantly influences the concentration of platelet growth factors (IGF-1: p = 0.025 and PDGF-B: p = 0.012). There was a relationship between the type of renal replacement therapy and the duration of dialysis, and the concentration of IGF-1, PDGF-B (p < 0.00001, p < 0.001).

CONCLUSIONS

The type of renal replacement therapy has a different effect on the concentration of platelet-derived growth factors IGF-1 and PDGF-B. PD patients had the highest concentrations of all growth factors, and this may be due to the presence of inflammation induced by dialysis-related advanced end-products of glycosylation (AGE).

Protective effects of pterostilbene on ulcerative colitis in rats via suppressing NF-κB pathway and activating PPAR-γ

Our study aimed to investigate the protective effects and potential mechanisms of pterostilbene on rats with ulcerative colitis (UC). We established 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced colitis rat model. Rats were randomly divided into three groups, including control group, model group, and pterostilbene group (30 mg/kg). Disease activity index (DAI) including body weight, stool consistency, and gross bleeding was measured. The concentration of superoxide dismutases (SODs), glutathione superoxide (GSH-px), malondialdehyde (MDA), and methylpropanediol (MPO) in serum were detected by enzyme-linked immunosorbent assay (ELISA). The levels of interleukin-1 beta (IL-1β), IL-17, IL-6, and tumor necrosis factor–alpha (TNF-α) in serum were also analyzed by ELISA kits. Histological evaluations of colons were conducted. The levels of peroxisome-proliferator-activated receptor–γ (PPAR-γ), nuclear factor-κB (NF-κB), ZO-1, and Occludin were analyzed by immunohistochemistry. Compared with model group, pterostilbene notably suppressed the production of TNF-α, IL-17, IL-1β, IL-6, MDA and MPO in serum, and markedly increased the SOD and GSH-Px activity in serum. Pterostilbene significantly attenuated macroscopic damage and histological injury, when compared with model rats. Furthermore, pterostilbene also markedly activated the expression of PPAR-γ, ZO-1, and Occludin, and suppressed the expression of NF-κB. The protective effects of pterostilbene might be associated with suppression of NF-κB and activation of PPAR-γ. Pterostilbene might be a promising therapeutic agent for colitis treatment.

Portulaca Extract Attenuates Development of Dextran Sulfate Sodium Induced Colitis in Mice through Activation of PPARγ

Portulaca oleracea L. is a traditional Chinese medicine, which has been used as adjuvant therapy for inflammatory bowel disease (IBD). However, the mechanism of its activity in IBD still remains unclear. Since previous studies have documented the anti-inflammatory effect of peroxisome proliferator activated receptors-γ (PPAR-γ), Portulaca regulation of PPAR-γ in inflammation was examined in current study. Ulcerative colitis (UC) was generated by 5% dextran sulfate sodium (DSS) in mice and four groups were established as normal control, DSS alone, DSS plus mesalamine, and DSS plus Portulaca. Severity of UC was evaluated by body weight, stool blood form, and length of colorectum. Inflammation was examined by determination of inflammatory cytokines (TNF-a, IL-6, and IL-1a). Portulaca extract was able to attenuate development of UC in DSS model similar to the treatment of mesalazine. Moreover, Portulaca extract inhibited proinflammatory cytokines release and reduced the level of DSS-induced NF-κB phosphorylation. Furthermore, Portulaca extract restored PPAR-γ level, which was reduced by DSS. In addition, Portulaca extract protected DSS induced apoptosis in mice. In conclusion, Portulaca extract can alleviate colitis in mice through regulation of inflammatory reaction, apoptosis, and PPAR-γ level; therefore, Portulaca extract can be a potential candidate for the treatment of IBD.

Cardiovascular risks in chronic kidney disease pediatric patients

One of the common factors for the premature death in children is advanced chronic kidney disease (CKD). Most often cardiovascular disease (CVD) is the reason for mortality. The cardiovascular (CV) morbidity starts early in the disease process and renal transplanted children (CKD-T) are also at risk. The present review is focused on the current views of the cardiovascular risks during CKD in pediatric patients. Variable data sources for the latest literature collection were explored which mainly included PubMed and Google Scholar. The most important risk factors for subclinical CVD were a young age, elevated BMI and systolic blood pressure z-scores as well as a low GFR and present albuminuria. Increasing blood pressure and BMI over follow-up were also important cardiac risk factors longitudinally. The present review concludes that altered cardiac function and remodeling are a concurrent part of the CKD process, start early in the disease development, and persist after renal transplantation. The findings suggest that children with CKD or CKD-T are at high risk for future CVD where younger patients with elevated BMI and slightly increased blood pressures, as well as present albuminuria, are those at greatest risk, thus indicating targets for future interventions.

Association of Myeloperoxidase and the Atherogenic Index of Plasma in Children with End-Stage Renal Disease

BACKGROUND

The aim of this study was to explore oxidative stress status, especially the enzyme myeloperoxidase in children with end-stage renal disease. Also, we investigated possible associations between the atherogenic index of plasma and these parameters.

METHODS

Lipid status parameters, oxidative stress status parameters, and myeloperoxidase concentration were measured in the sera of 20 children in the last stage of chronic renal disease (ESRD) and 35 healthy children of matching age and sex. The Atherogenic Index of Plasma (AIP) was calculated according to the appropriate equation.

RESULTS

We did not find any significant differences in myeloperoxidase concentrations between the investigated groups (p=0.394). Oxidative stress parameters were, however, significantly higher in the patient group (p<0.001), as well as the atherogenic index of plasma (p<0.001). Myeloperoxidase concentration and advanced oxidation protein product (AOPP) concentration were independently associated with increased AIP in the patient group (p<0.05).

CONCLUSIONS

Changes in AIP in children with ERSD are associated with the oxidative stress status and myeloper-oxidase concentration.

Regulation of urinary crystal inhibiting proteins and inflammatory genes by lemon peel extract and formulated citrus bioflavonoids on ethylene glycol induced urolithic rats

The objective of this study is to check the regulation of crystal matrix proteins and inflammatory mediators by citrus bioflavonoids (CB) and Lemon peel (LP) extract in hyperoxaluric rats. The animals were divided into six groups with 6 animals each. Group 1: Control, Group 2: Urolithic (Ethylene glycol (EG)-0.75%); Group 3 & 5: Preventive study (EG + CB (20 mg/kg body weight) and LP (100 mg/kg body weight) extract administration from 0th-7th week) respectively; Group 4 & 6: Curative study (EG + CB and LP extract administration from 4th-7th week) respectively by oral administration. Urinary lithogenic factors (Calcium, oxalate, phosphate and citrate) were normalized in CB & LP supplemented rats, while serum parameters revealed the nephroprotective nature of the intervening agents compared to urolithic rats (p < 0.001). Immunoblotting studies showed significantly increased expression of THP, osteopontin and transferrin in kidneys of urolithic rats (p < 0.001), while preventive and curative study showed near normal expression of these proteins. Expression of NF-κB, TNF-α and IL-6 were raised significantly (p < 0.001), while a very minimal increase in MCP-1 expression was observed in urolithic rats compared to control. Hence, supplementation of CB and LP reduced the crystal promoting factors and provides protection from crystal induced renal damage.

The role of ions, heavy metals, fluoride, and agrochemicals: critical evaluation of potential aetiological factors of chronic kidney disease of multifactorial origin (CKDmfo/CKDu) and recommendations for its eradication

The pollution of water and food through human waste and anthropogenic activities, including industrial waste and agricultural runoff, is a mounting problem worldwide. Water pollution from microbes causes identifiable diarrhoeal illnesses. The consumption of water contaminated with heavy metals, fluoride, and other toxins causes insidious illnesses that lead to protracted, non-communicable diseases and death. Chronic kidney disease of unusual/uncertain/unknown aetiology is one such example, began to manifest in the mid-1960s in several dry-zonal agricultural societies in developing economies that are located around the equator. In Sri Lanka, such a disease is affecting the North Central Province, the rice bowl of the country that first appeared in the mid-1990s. Several potential causes have been postulated, including heavy metals, fluoride, cyanobacterial and algae toxins, agrochemicals, and high salinity and ionicity in water, but no specific source or causative factor has been identified for CKD of multifactorial origin (CKDmfo). Three large studies conducted in the recent past failed to find any of the postulated components (heavy metals, cyanobacterial toxins, fluoride, salinity, or agrochemicals) at levels higher than those deemed safe by the World Health Organization and the US Environmental Protection Agency. At the reported low levels in water and with the heterogeneous geographical distribution, it is unrealistic to expect any of these components individually could cause this disease. However, the additive or synergistic effects of a combination of factors and components, even at lower exposure levels, together with malnutrition and harmful behaviours, and/or a yet-unidentified (or not investigated) toxin, can cause this epidemic. Because the cause is unknown, scientists need to work on broader hypotheses, so that key causative elements are not missed. Taken together the plausibility of multiple factors in the genesis of this disease, the appropriate terminology is CKDmfo, a name that also indicates the need for multi-disciplinary research programs to facilitate identifying the cause(s) and the need for multiple approaches to eradicate it. While some potential causes remain to be investigated, existing data point to polluted water as the main source of this disease. This article evaluates pros and cons of each hypothesis and highlights the importance of among others, providing clean water to all affected and surrounding communities. Available data do not support any of the postulated agents, chemicals, heavy metals, fluoride, salinity/ionicity, or individual agrochemical components, such as phosphate or glyphosate, as causative factors for CKDmfo in Sri Lanka. However, as the CKDmfo name implies, a combination of these factors (or an unknown toxin) together with harmful behaviour and chronic dehydration may cause this disease. Irrespective of the cause, prevention is the only way forward for eradication.

Effect of vitamin C on endothelial function of children with chronic renal failure: An experimental study

Background:

It is well established that improvement of endothelial dysfunction (ED) could prevent or delay the occurrence of cardiovascular disease (CVD) and its related morbidity and mortality in patients with chronic kidney disease (CKD). In this study we investigated whether administration of vitamin C could be effective by improving brachial artery flow-mediated dilation (FMD) and intima media thickness (IMT), two surrogate markers of ED, in children with CKD or chronic renal failure (CRF).

Materials and Methods:

In this analytic-experimental study children aged 3-18 years with a diagnosis of CRF and a group of healthy children were enrolled. Vitamin C (250 mg/day) administrated for the two studied groups for 1 month. Endothelial function was evaluated by FMD and IMT measurement using vascular Doppler ultrasonography, before and after trial.

Results:

In this study 18 patients with CRF and 19 normal children as the control group were studied. At baseline mean of IMT and FMD was not different in the two studied groups (P > 0.05). After vitamin C administration IMT decreased significantly in the two studied groups (P < 0.05). FMD increased in the two studied groups but the difference was significant in the control group (P < 0.05).

Conclusion:

The findings of this interventional trial have demonstrated that vitamin C could have protective effect on ED of patients with CRF possibly in those with severe form of the disease but for obtaining more conclusive results larger sample size is needed.

Biochemical assessment of oxidative status versus liver enzymes in patients with chronic fascioliasis

The aim of this study was to examine the oxidative status in Egyptian patients suffering chronic fascioliasis. The relationship between serum malondialdehyde (MDA) levels, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities was investigated in relation to the level of liver enzymes; ALT and AST compared to healthy controls. Twenty patients versus ten controls were included in the study. Among cases the MDA, CAT, AST and ALT were higher than controls, while SOD and GPX higher values were present among controls. There was a highly significant difference between cases and controls as regard MDA, CAT, SOD, GPX, and AST, and a significant difference regarding ALT. The findings of increased serum lipid peroxidation and decreased antioxidant enzymes in erythrocytes of chronic fascioliasis patients indicated the presence of persistent inflammation and oxidative stress which confirms the underlying pathogenesis and reflected the stage of infection providing a baseline data for comparison between normal and infected patients guided by the level of liver enzymes in relation to oxidative status.

Investigating the role of cardiovascular biomarkers in children with pre-dialysis chronic kidney disease: a substitute to echocardiography to detect increased left ventricular mass?

BACKGROUND

Children with chronic kidney disease (CKD) are at increased risk of future cardiovascular (CV) events. Our aim in this prospective single-centre cross-sectional analysis was to assess the relationship of a novel panel of CV biomarkers with left ventricular hypertrophy (LVH).

METHODS

A panel of five CV biomarkers (asymmetric dimethyl arginine, high sensitivity C-reactive protein, homocysteine, N-terminal pro-B type natriuretic peptide and uric acid) were measured on the same day as an echocardiogram assessment, in paediatric patients with pre-dialysis stages 3-5 of CKD.

RESULTS

Of 73 children aged 5-18 years, LVH, all eccentric, was identified in 38%. Systolic blood pressure (BP), glomerular filtration rate (GFR) and higher intake of calcium-based phosphate binders were significantly worse in children with LVH. In multivariate models analysing each biomarker one at a time with confounders [GFR, systolic BP z-score, anti-hypertensive medication (yes/no) and elemental calcium intake], clinic systolic BP z-score and elemental calcium intake consistently displayed a significant relationship with indexed left ventricular mass (LVMI). None of the evaluated CV biomarkers displayed a significant relationship with LVMI.

CONCLUSIONS

In our cohort of children with moderately severe pre-dialysis CKD we have identified no suitable biomarkers to detect LVH. We would therefore recommend that echocardiographic determination of LVMI remains the technique of choice for detection of LVH in children with CKD.

Serum malondialdehyde levels, myeloperoxidase and catalase activities in patients with nephrotic syndrome

OBJECTIVES

Some studies have indicated the pathophysiological importance of reactive oxygen species (ROS) in patients with nephrotic syndrome. Myeloperoxidase (MPO) is a leukocyte-derived enzyme-generating ROS that has been proposed to exert a wide array of pro-atherogenic effects throughout all stages of the atherosclerotic process. The aim of this study was to investigate the serum malondialdehyde (MDA) levels, MPO and catalase activities in patients with adult nephrotic syndrome.

PATIENTS AND METHOD

s Twenty-four patients with nephrotic syndrome and 24 healthy controls were enrolled. Serum MPO activity, catalase activity, and MDA levels were assessed.

RESULTS

Serum MPO activity and MDA levels were significantly higher in patients with nephrotic syndrome than controls (both, P<0.001), while catalase activity was significantly lower (P<0.001). Serum catalase activity was found to be significantly correlated with MPO activity (r=-0.417, P=0.003) and MDA levels (r=-0.532, P=0.007). The serum MDA levels were also found to be significantly correlated with MPO activity (r=0.419, P=0.003).

CONCLUSIONS

We concluded that serum MPO activity and oxidative stress were increased and that serum catalase activity was decreased in patients with adult nephrotic syndrome. In addition, these results indicate that increased MPO activity is associated with an oxidant-antioxidant imbalance that may contribute to atherosclerosis in patients with adult nephrotic syndrome.

Left ventricular diastolic dysfunction by tissue Doppler echocardiography in pediatric chronic kidney disease

BACKGROUND

Myocardial dysfunction is common in chronic kidney disease (CKD) and related to poor outcomes. New non-invasive methods to assess cardiac function have been introduced, but comparative studies evaluating their clinical usefulness in pediatric CKD are lacking. We studied left ventricular (LV) function in pediatric CKD and renal transplant patients, comparing conventional pulse-wave Doppler echocardiography (cPWD) with newer tissue Doppler imaging (TDI) and relating the results to known cardiovascular risk factors.

METHODS

The study included 34 children/adolescents with CKD stages 2-5, 44 renal transplant patients and 19 patients with a normal renal function. The mean age was 11.4 (range 0.8-18.8) years.

RESULTS

Both patient groups had significantly lower LV diastolic function than those with a normal renal function. The most sensitive determinants were TDI E'/A' and cPWD E/TDI E' ratios. In a stepwise linear regression analysis, high blood pressure, young age and the presence of albuminuria all independently predicted LV diastolic function.

CONCLUSIONS

Our study confirms the high prevalence of LV diastolic dysfunction in pediatric CKD patients and following renal transplantation, where TDI appears to be more sensitive than cPWD in assessing early myocardial dysfunction. Our results also underline the importance of preventive measures, such as rigorous blood pressure control, in pediatric CKD.

Hyperlipidemia, oxidative stress, and intima media thickness in children with chronic kidney disease

BACKGROUND

The roles of dyslipidemia and oxidative stress in the early phases of atherosclerosis were tested in children with chronic kidney disease (CKD). Intima media thickness of common carotid arteries (cIMT) is used as a measure of early atherosclerosis.

METHODS

Fifty-two pediatric CKD patients were enrolled in the study (10 with chronic renal failure [CRF], 22 with a renal transplant [RT], 20 with chronic hemodialysis (cHD) patients, and 36 healthy children (control group, CG). Lipid status, oxidative stress, and paraoxonase 1 (PON1) status were assessed. cIMT was measured by ultrasound, adjusted for age and sex, and presented as standard deviation scores (SDS).

RESULTS

Children with CKD had disturbed lipid content, which was most pronounced in cHD children, with higher free cholesterol and triglycerides compared with healthy children. Oxidative stress was markedly increased (malodialdehyde [MDA, μmol/L]: CRF 1.50 ± 0.26, RT 1.55 ± 0.40, cHD 1.77 ± 0.34, CG 0.97 ± 0.33, p < 0.001) and antioxidative defense was compromised (superoxide dismutase [SOD, U/L]: CG 120 ± 21, CRF 84 ± 25, RT 93 ± 12, cHD 119 ± 37, p < 0.001). Multiple linear regression analysis showed that a model that included disease duration, blood pressure, urea, lipid, and oxidative status parameters accounted for more than 90% of the variability of cIMT-SDS.

CONCLUSIONS

Early atherosclerosis in CKD children is caused, at least in part, by dyslipidemia and oxidative stress. Monitoring of vessel wall changes, along with assessment of oxidative stress status and high density lipoprotein (HDL) functionality is necessary to ensure better therapeutic strategies for delaying atherosclerotic changes in their asymptomatic phase.

The relationship between glutathione peroxidase and bioimpedance parameters in nondiabetic hemodialysis patients

There is growing evidence from experimental and clinical studies that oxidative stress is involved in the pathogenesis of malnutrition. This cross-sectional study aimed to investigate the relationship between glutathione peroxidase (GPx) levels as a marker of antioxidant status and the nutritional status assessed by bioimpedance analysis (BIA). Ninety-seven nondiabetic stable outpatient uremic adults undergoing chronic hemodialysis (HD) were recruited for this study. Impedance measurements were performed using a multifrequency bioelectrical impedance analyzer after dialysis. GPx levels correlated with intracellular water (ICW) (r = 0.341, P = 0.011), ICW/total body weight (r = 0.320, P = 0.017), lean body mass (r = 0.300, P = 0.026) and total body cell mass (r = 0.339, P = 0.011). When patients were divided into two groups according to mean GPx levels (83.9 U/gr hemoglobin), the patients with higher GPx (GPx > 83.9 U/gr hemoglobin) had higher albumin (P = 0.038), lean body mass (P = 0.026), ICW (P = 0.011), and total body cell mass (P = 0.011) compared with those with lower GPx (GPx ≤ 83.9 U/gr hemoglobin). Furthermore, in the patients with higher GPx, body fat; extracellular water/total body water; illness marker and body fat mass index were lower than other group. In conclusion, our results reveal correlation indicating a relationship between antioxidant status (as measured by GPx) and nutritional status as assessed by BIA in nondiabetic HD patients.

Hypoxia and oxidative stress markers in pediatric patients undergoing hemodialysis: cross section study

Background

Tissue injury due to hypoxia and/or free radicals is common in a variety of disease processes. This cross-sectional study aimed to investigate effect of chronic kidney diseases (CKD) and hemodialysis (HD) on hypoxia and oxidative stress biomarkers.

Methods

Forty pediatric patients with CKD on HD and 20 healthy children were recruited. Plasma hypoxia induced factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) were measured by specific ELISA kits while, total antioxidant capacity (TAC), total peroxide (TPX), pyruvate and lactate by enzymatic/chemical colorimetric methods. Oxidative stress index (OSI) and lactate/pyruvate (L/P) ratio were calculated.

Results

TAC was significantly lower while TPX, OSI and VEGF were higher in patients at before- and after-dialysis session than controls. Lactate and HIF-1α levels were significantly higher at before-dialysis session than controls. Before dialysis, TAC and L/P ratio were lower than after-dialysis. In before-dialysis session, VEGF correlated positively with pyruvate, HIF-1α and OSI correlated positively with TPX, but, negatively with TAC. In after-dialysis session, HIF-1α correlated negatively with TPX and OSI; while, OSI correlated positively with TPX.

Conclusions

CKD patients succumb considerable tissue hypoxia with oxidative stress. Hemodialysis ameliorated hypoxia but lowered antioxidants as evidenced by decreased levels of HIF-1α and TAC at before- compared to after-dialysis levels.

Serum myeloperoxidase activity and oxidative stress in patients with acute brucellosis

OBJECTIVES

The role of infection in the pathogenesis of atherosclerosis has been increasingly discussed. Previous studies have suggested that increased myeloperoxidase activity plays an important role in the pathogenesis of atherosclerosis. The aim of this study was to investigate the serum myeloperoxidase activity and catalase activity along with lipid hydroperoxide (LOOH) levels in patients with acute brucellosis.

DESIGN AND METHODS

Thirty-two patients with brucellosis and 33 healthy controls were enrolled. Serum myeloperoxidase activity, catalase activity and LOOH levels were determined.

RESULTS

Serum myeloperoxidase activity and LOOH levels were significantly higher in patients with brucellosis than controls (p<0.05, p<0.001), while catalase activity were significantly lower (p<0.001). LOOH levels were found to be significantly positively correlated with MPO activity (r=0.297, p=0.016) in patients.

CONCLUSIONS

These results indicate that increased myeloperoxidase activity and decreased catalase activity is associated with increased oxidative stress, which may have a role in atherosclerotic processes in brucellosis patients.

Evaluation of oxidative status in patients with Fasciola hepatica infection

BACKGROUND

F. hepatica infection is rare and mostly subclinical. Migration of juvenile forms of F. hepatica into the host's liver is accompanied by an inflammatory reaction followed by fibrosis and cirrhosis.

OBJECTIVE

The aim of this study was to evaluate oxidative status by using a novel automated method in patients with Fasciola hepatica.

METHODS

Twenty two patients with a diagnosis of F. hepatica and 26 healthy volunteers were enrolled in the study. Their Total antioxidant capacity status (TAC), total oxidant status (TOS) and catalase were measured in them and oxidative stress index (OSI) was calculated. These measurements were also taken for the control group and the values were compared.

RESULTS

Plasma levels of total TOS and OSI were significantly increased in patients as compared with healthy controls (P<0.001, P<0.001, P=0.001, P=0.008) respectively. In contrast, TAC level was significantly lower in patients as compared with controls (p<0.05). There was no significant difference between the catalase results of the two groups (p>0.05).

CONCLUSION

Total oxidative status and OSI were increased and total antioxidative status capacity was decreased in patients with F. hepatica infection. A high oxidative stress occurs during F. hepatica infection, which may cause severe damage in both the liver.

Elastase, α1-proteinase inhibitor, and interleukin-8 in pre-dialyzed and hemodialyzed patients with chronic kidney disease

BACKGROUND

Neutrophil elastase in complex with α(1) -proteinase inhibitor (NE-α(1) PI) and interleukin (IL)-8 may serve as indicators of neutrophil activation and inflammatory stage. The aim of the study was to evaluate NE-α(1) PI, α(1)-PI, and IL-8 levels in the blood of patients with chronic kidney disease (CKD) undergoing hemodialysis (HD) or conservatively treated (CT). The influence of a single HD session on the investigated parameters was also assessed.

METHODS

Blood samples were obtained from two groups of hemodialyzed patients (children/young adults [group HD1, n = 8] and adults [group HD2, n = 13]), as well as 13 CT patients and a group of healthy subjects. The proteins were measured using enzyme-linked immunosorbent assay or radial immunodiffusion.

RESULTS

There were no significant differences in NE-α(1) PI, α(1)-PI, and IL-8 concentrations between the HD1 and HD2 patients. The levels of NE-α(1) PI were considerably higher than normal in both groups of HD patients (before and after the HD session) and in the CT patients. Higher titers of NE-α(1) PI (P < 0.05) and α(1)-PI (P < 0.01) were obtained in the adults during the course of HD. Increased NE-α(1) PI was positively correlated with α(1)-PI. The serum concentration of IL-8 was significantly higher in the HD2 patients before and after dialysis than in the controls.

CONCLUSIONS

The data indicate that in CKD patients, neutrophils are highly activated both in the pre-dialyzed period and on regular HD. Contact with the dialysis membrane during HD causes a significant increase in blood NE-α(1) PI and α(1)-PI in adults, but not in children/young adults. NE-α(1) PI seems to be a much better indicator of an inflammatory state in CKD patients than free α(1)-PI or IL-8.

Parameters of oxidative stress and echocardiographic indexes in patients on dialysis therapy

AIM

Quantity of oxidative stress (OS) is enhanced in every stage of chronic renal failure (CRF). OS and its effects on echocardiographic indexes in patients on hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) were evaluated.

MATERIALS AND METHODS

Thirty-nine patients on CAPD, 32 patients on HD, and 30 healthy individuals with similar demographic features were included. Patients with diabetes mellitus and chronic inflammatory diseases were excluded. Blood samples were collected to examine hematological and biochemical parameters and levels of malonyldialdehyde (MDA), glutathione peroxidase (GSH-px), and superoxide dismutase (SOD) after a 12-hour fasting period in the middle of dialysis week. OS parameters were compared with ejection fraction (EF), interventricular septum diameter (IVSd), left ventricular posterior wall diameter (LVPWd), and left atrium diameter (LAd) determined in M-mod echocardiographic examination.

RESULTS

No significant difference was observed between MDA and GSH-px levels of patients and control group; however, SOD levels of patients group were significantly lower (p<0.0001). SOD levels of patients on HD were lower than that of patients on CAPD (p=0.039). Negative correlation was detected between MDA and EF (r=-0.380, p=0.001); SOD has negative correlation with systolic blood pressure (r=-0.265, p=0.011), diastolic blood pressure (r=-0.230, p=0.028), phosphorus (r=-0.327, p=0.001), intact parathyroid hormone (iPTH) (r=-0.259, p=0.013), C-reactive protein (CRP) (r=-0.235, p=0.024), fibrinogen (r=-0.342, p=0.001), and total cholesterol (r=-0.249, p=0.017); and positive correlation with hemoglobin (r=0.414, p<0.001) and albumin (r=0.367, p<0.001). MDA was independently related with age (beta=-0.258, p=0.035), male gender (beta=-0.312, p=0.004), and EF (beta=-0.461, p<0.001). No correlation was determined between antioxidants and cardiac indexes.

CONCLUSION

SOD levels decreased significantly especially in patients on HD, and it was observed that lower levels of SOD would lead to OS in patients on HD and CAPD when compared to healthy individuals; MDA levels were independently influenced from EF.

Proteome profile of peritoneal effluents in children on glucose- or icodextrin-based peritoneal dialysis

BACKGROUND

We compared the proteome profile of peritoneal effluents obtained with icodextrin (Ico) or glucose (Glu) in paediatric patients and defined the oxido-redox status of proteins.

METHODS

Sixteen patients underwent two 14-h daytime dwells performed on subsequent days with 7.5% Ico and 3.86% Glu solutions. Protein composition was analysed by two-dimensional electrophoresis and mass spectrometry; oxidized products were evaluated by cyanine labelling.

RESULTS

Peritoneal transport kinetics of β2-microglobulin and cystatin C was linear for both solutions, but was significantly higher with Ico than with Glu, suggesting a better efficiency for these molecules. There was a linear correlation between total protein removal during Ico and Glu dialysis in the same patient, suggesting that it is a function of peritoneal membrane characteristics. The ratio between proteins removed by Ico and by Glu solutions was higher at low removal rate. Image gel analysis revealed 1064 and 774 spots, respectively, in Ico and Glu solutions; 524 were common, and 314 were higher in Ico than Glu effluents. Analysis of protein oxido-redox status showed a greater amount of oxidized albumin in Ico dialysate that was correlated with lower serum levels.

CONCLUSIONS

Our results indicate a better efficiency of Ico in removing small proteins. Removal of big proteins and their oxidized isoforms reflects potentially opposite effects. The long-term clinical consequences of removing also potentially important molecules are to be defined.

Early origins of cardiovascular disease in pediatric chronic kidney disease

The importance of cardiovascular disease in adults with chronic kidney disease is now well recognized. For children who develop chronic kidney disease, cardiovascular disease is also a leading cause of eventual morbidity and mortality. Although the clinical manifestations of cardiovascular disease may not be apparent until later, early subclinical findings can be observed even during childhood. This review updates the reader on the epidemiology of cardiovascular disease in pediatric chronic kidney disease, discusses risk factors and potential mechanisms of accelerated cardiovascular disease, reviews evidence of early manifestations of cardiovascular disease in pediatric chronic kidney disease, and briefly discusses prevention and treatment strategies.

Oxidative stress and neutrophil function in cats with chronic renal failure

BACKGROUND

Oxidative stress is an important component in the progression of chronic renal failure (CRF) and neutrophil function may be impaired by oxidative stress.

HYPOTHESIS

Cats with CRF have increased oxidative stress and decreased neutrophil function compared with control cats.

ANIMALS

Twenty cats with previously diagnosed renal failure were compared with 10 age-matched control cats.

METHODS

A biochemical profile, CBC, urinalysis, antioxidant capacity, superoxide dismutase (SOD) enzyme activity, reduced to oxidized glutathione ratio (GSH : GSSG), and neutrophil phagocytosis and oxidative burst were measured. Statistical comparisons (2-tailed t-test) were reported as mean +/- standard deviation.

RESULTS

The CRF cats had significantly higher serum blood urea nitrogen, creatinine, and phosphorus concentrations than control cats, and significantly lower PCV and urine specific gravity than control cats. The GSH : GSSG ratio was significantly higher in the CRF group (177.6 +/- 197, 61.7 +/- 33; P < .02) whereas the antioxidant capacity was significantly less in the CRF group (0.56 +/- 0.21, 0.81 +/- 0.13 Trolox units; P < .005). SOD activity was the same in control and CRF cats. Neutrophil oxidative burst after Escherichia coli phagocytosis, measured as an increase in mean fluorescence intensity, was significantly higher in CRF cats than controls (732 +/- 253, 524 +/- 54; P < .05).

CONCLUSIONS

The higher GSH : GSSG ratio and lower antioxidant capacity in CRF cats is consistent with activation of antioxidant defense mechanisms. It remains to be determined if supplementation with antioxidants such as SOD beyond the level of control cats would be of benefit in cats with CRF.

The heat shock protein profile in children with chronic kidney disease

OBJECTIVES

Chronic kidney disease (CKD) due to inflammation, lipid disorders, and endothelial dysfunction predisposes to accelerated atherosclerosis. Elevated levels of heat shock proteins (HSPs) and antibodies against them have been described in adults with atherosclerotic lesions and cardiovascular events. However, there are no investigations of these variables in children with CKD treated conservatively or on peritoneal dialysis. Therefore, we decided to evaluate the profile of HSPs and their potential role as markers of atherosclerosis in these groups of patients.

METHODS

The study group consisted of 37 children with CKD treated conservatively and 19 children and young adults on automated peritoneal dialysis (APD). The control group comprised 15 age-matched subjects with normal kidney function. HSP-60, HSP-70, HSP-90alpha, anti-HSP-60, anti-HSP-70, sE-selectin, and interleukin (IL)-4 serum concentrations were assessed by ELISA; high-sensitivity C-reactive protein (hs-CRP) serum levels were assessed by nephelometry. Serum lipid profiles (total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglycerides) were also estimated.

RESULTS

HSP-90alpha, anti-HSP-60, and sE-selectin concentrations in the CKD and APD patients were higher than in the controls and were lower in the predialysis subjects than in the children on dialysis. Median values of anti-HSP-70 were higher in the CKD patients than in the control group. Levels of IL-4 were increased in all patients versus controls. Median values of HSP-60 were decreased in the CKD and APD children versus controls. HSP-70 and hs-CRP concentrations were comparable in all groups.

CONCLUSIONS

The altered HSP and anti-HSP concentrations may imply that the response to stress conditions in the course of CKD is disturbed in children; APD does not aggravate that dysfunction in a significant way. Relationships between HSPs, lipid profile, and markers of inflammation suggest a possible role of the selected HSPs as markers of atherosclerosis in children with CKD.

Oxidative stress in children on hemodialysis: value of autoantibodies against oxidized low-density lipoprotein

The principal causes of morbidity and mortality in children with chronic renal failure on maintenance hemodialysis are cardiovascular complications. Recently, it has been suggested that oxidative stress, chronic inflammation and malnutrition are risk factors for cardiovascular disease. However, to date, biomarkers of oxidative stress have not been well studied in children. The aim of this study was to investigate the relationship between oxidative stress and cardiovascular risk factors in children on hemodialysis therapy. Twenty-eight hemodialysis patients (13 females, 15 males; mean age 15.1 +/- 2.5 years) and 20 healthy children (13 females, seven males; mean age 14.3 +/- 2.7 years) were included in the study. Levels of antibodies to oxidized low-density lipoprotein (oLABs), high sensitivity C-reactive protein (hs-CRP), albumin, prealbumin, transferrin, and ferritin were measured. Antibodies to oxidized low-density lipoprotein (LDL) in hemodialysis patients were lower than those in the controls (P < 0.05). The patients with lower oLAB titers had higher levels of hs-CRP and ratio of erythropoietin to hematocrit (EPO/Htc), and lower levels of albumin, prealbumin, apolipoprotein A-1 (ApoA(1)), and high-density lipoprotein (P < 0.05). Antibodies to oxidized LDL in hemodialysis patients with dyslipidemia were lower than those of patients with normal lipid profile (P < 0,05). This study showed that children treated by hemodialysis are exposed to oxidative stress and chronic inflammation. We suggest that oLAB levels are decreased in children on hemodialysis as a result of severe oxidative stress and that these antibodies are related to inflammation, anemia, malnutrition and dyslipidemia.

Alpha-tocopherol supplementation decreases electronegative low-density lipoprotein concentration [LDL(-)] in haemodialysis patients

BACKGROUND

Oxidative stress is a significant contributor to cardiovascular diseases (CVD) in haemodialysis (HD) patients, predisposing to the generation of oxidized low-density lipoprotein (oxLDL) or electronegatively charged LDL subfraction. Antioxidant therapy such as alpha-tocopherol acts as a scavenger of lipid peroxyl radicals attenuating the oxidative stress, which decreases the formation of oxLDL. The present study was designed to investigate the influence of the alpha-tocopherol supplementation on the concentration of electronegative low-density lipoprotein [LDL(-)], a minimally oxidized LDL, which we have previously described to be high in HD patients.

METHODS

Blood samples were collected before and after 120 days of supplementation by alpha-tocopherol (400 UI/day) in 19 stable HD patients (50 +/- 7.8 years; 9 males). The concentrations of LDL(-) in blood plasma [using an anti-LDL- human monoclonal antibody (mAb)] and the anti-LDL(-) IgG auto-antibodies were determined by ELISA. Calculation of body mass index (BMI) and measurements of waist circumference (WC), triceps skin folds (TSF) and arm muscle area (AMA) were performed.

RESULTS

The plasma alpha-tocopherol levels increased from 7.9 microM (0.32-18.4) to 14.2 microM (1.22-23.8) after the supplementation (P = 0.02). The mean concentration of LDL(-) was reduced from 570.9 microg/mL (225.6-1241.0) to 169.1 microg/mL (63.6-621.1) (P < 0.001). The anti-LDL(-) IgG auto-antibodies did not change significantly after the supplementation. The alpha-tocopherol supplementation also reduced the total cholesterol and LDL-C levels in these patients, from 176 +/- 42.3 mg/dL to 120 +/- 35.7 mg/dL (P < 0.05) and 115.5 +/- 21.4 mg/dL to 98.5 +/- 23.01 mg/dL (P < 0.001), respectively.

CONCLUSION

The oral administration of alpha-tocopherol in HD patients resulted in a significant decrease in the LDL(-), total cholesterol and LDL-C levels. This effect may favour a reduction in cardiovascular risk in these patients, but a larger study is required to confirm an effect in this clinical setting.

Oxidative stress is associated with arterial dysfunction and enhanced intima-media thickness in children with hypercholesterolemia: the potential role of nicotinamide-adenine dinucleotide phosphate oxidase

BACKGROUND

Endothelial dysfunction and intima-media thickness are precocious manifestations of hypercholesterolemia, but the mechanism is unclear.

OBJECTIVE

The aim of the study was to analyze the interplay among endothelial dysfunction, intima-media thickness, and oxidative stress in children with hypercholesterolemia.

METHODS

We performed a cross-sectional study comparing flow-mediated dilation, intima-media thickness, lipid profile, urinary isoprostanes as markers of oxidative stress, and platelet expression of gp91(phox), the catalytic unit of nicotinamide-adenine dinucleotide phosphate oxidase, in a population of 50 children with hypercholesterolemia (mean age +/- SD: 10.0 +/- 3.7 years) and 50 children without hypercholesterolemia (mean age: 9.2 +/- 3.5 years). Four children with hereditary deficiency of gp91(phox) were studied also.

RESULTS

Children with hypercholesterolemia had reduced flow-mediated dilation (mean +/- SD: 6.2 +/- 2.4 vs 9.2 +/- 2.5%) and enhanced intima-media thickness (0.45 +/- 0.07 vs 0.40 +/- 0.06 mm), urinary isoprostanes (86.9 +/- 51.6 vs 45.9 +/- 25.6 pg/mg creatinine), and gp91(phox) platelet expression (4.4 +/- 3.8 vs 2.0 +/- 1.7 mean fluorescence) compared with control subjects. At bivariate analysis, flow-mediated dilation was correlated with low-density lipoprotein cholesterol, intima-media thickness, urinary isoprostanes, and platelet gp91(phox). Stepwise multiple linear regression analysis showed that, in children with hypercholesterolemia, flow-mediated dilation and intima-media thickness were significantly associated with low-density lipoprotein cholesterol and urinary isoprostanes; also, gp91(phox) platelet expression was an independent predictor of urinary isoprostanes. Children with gp91(phox) hereditary deficiency showed downregulation of platelet gp91(phox) and reduced urinary excretion of isoprostanes.

CONCLUSIONS

The study suggests that gp91(phox)-mediated oxidative stress may have a pathogenic role in the anatomic and functional changes of the arterial wall occurring in children with premature atherosclerosis.

Oxidative Stress in Children on Peritoneal Dialysis

Objectives

Enhanced oxidative stress has been observed in dialysis and predialysis adult patients with chronic kidney disease (CKD), which resulted in increased mortality and morbidity within this population. Not much attention in the literature has been paid to nonenzymatic antioxidant defense in children with CKD on peritoneal dialysis (PD). The aim of the present study was to describe the plasma, erythrocyte, and dialysate concentrations of oxidized (GSSG) and reduced glutathione (GSH) and vitamins A, E, and C in a pediatric PD population.

Patients

10 children on PD and 27 age-matched healthy subjects were enrolled in the study.

Results

Erythrocyte and plasma GSH concentrations were lower in PD patients, erythrocyte concentration of GSSG remained unchanged, and plasma GSSG was significantly higher in children on PD. Children on PD exhibited decreased plasma concentrations of antioxidant vitamins compared to healthy subjects. Moreover, we documented loss of vitamins A, E, and C into ultrafiltrate.

Conclusion

Such low plasma levels of vitamins A, E, and C and simultaneously decreased activity of erythrocyte GSH may be responsible for the increased oxidative stress occurring in children with CKD on PD.

Carotid intima-media thickness in children and young adults with renal transplant: Internal carotid artery vs. common carotid artery

Cardiovascular diseases are the main causes of morbidity and mortality following renal transplantation. Atherosclerotic structural changes, which can be detected by high-resolution B-mode ultrasonography, begin before clinical findings. However, little is known about the extent of these abnormalities in children after renal transplantation. We aimed to determine early structural changes of large arteries in renal transplant recipients without cardiovascular disease and to evaluate the role of clinical and laboratory features on IMT of carotid arteries. IMT and hemoglobin, serum levels of creatinine, acute phase proteins, lipid profile, and homocysteine were examined in 24 asymptomatic renal transplant recipients (median age 16.5 yr; range 8-25), and 20 healthy controls (median age 16 yr; range 9-24). CCA and ICA were evaluated in patients and controls with a high-resolution B-mode ultrasonography in multiple projections to optimize detection of carotid IMT. Measurement of IMT of both CCA [0.36 mm (range 0.16-0.48) vs. 0.28 mm (range 0.21-0.35), p < 0.001] and ICA [0.27 mm (range 0.16-0.48) vs. 0.22 mm (range 0.1-0.26), p < 0.001] were significantly higher in renal recipients than in healthy controls. Among several parameters assessed, only significant correlations were found between duration of CRF, duration of dialysis prior to transplantation and ICA-IMT (p = 0.06 and p = 0.02, respectively) and between mean past serum calcium-phosphorus ion product and CCA-IMT (p = 0.002). In conclusion, our observations indicate that vascular changes begin early in the course of CRF and are directly related to time on CRF and dialysis. These changes can be detected by measuring CCA/ICA-IMT ultrasonographically. We suggest that early renal transplantation can potentially avoid long-term cardiovascular events in children with end stage kidney disease.

Neutrophil activation, protein oxidation and ceruloplasmin levels in children with Henoch-Schönlein purpura

The aim of this study was to investigate the role of neutrophil activation, protein oxidation and ceruloplasmin (CLP) in the pathogenesis of Henoch-Schönlein purpura (HSP), which has not been investigated previously. Serum activities of myeloperoxidase (MPO) and arylesterase (ARYL) and levels of free thiol groups, CLP and total oxidant status (TOS) were measured in 29 children with HSP at the onset of the disease and during remission in comparison with 30 healthy subjects. Patients at active stage had significantly higher MPO activity (391+/-277 vs. 155+/-154 U/l, P<0.001), higher CLP (832+/-120 vs. 682+/-114 mg/dl, P<0.001) and TOS values (20.7+/-11.8 vs. 7.5+/-2.8 micromol H2O2/l, P<0.001) than the controls, respectively. Patients had significantly lower ARYL activity (158x10(3)+/-39x10(3) vs. 187x10(3)+/-46x10(3) U/l, P<0.001) and lower free thiol levels (234+/-48 vs. 279+/-26 micromol/l, P<0.001) than the controls, respectively. Significantly positive correlations were found between TOS and MPO (r=0.437, P=0.018) and TOS and CLP (r=0.409, P=0.028) at disease onset, whereas a negative correlation was found between MPO and thiol (r=-0.597, P=0.001) during remission. In conclusion, protein oxidation and neutrophil activation may play important roles in the pathogenesis of HSP. Further research is required to understand the potential linkage between oxidant stress and complications and to develop therapeutic strategies in HSP.

Relationship Between C-Reactive Protein and Atherosclerotic Risk Factors and Oxidative Stress Markers Among Young Persons 10–18 Years Old

Background: This study was undertaken to determine the association of serum C-reactive protein (CRP) with generalized and abdominal obesity, body fat composition, the metabolic syndrome, and oxidative stress markers among young people.

Methods: We conducted a population-based study of 512 young people, aged 10–18 years. We obtained anthropometric and blood pressure measurements. Fasting blood sugar, total cholesterol (TC), HDL-cholesterol, triglycerides, CRP, malondialdehyde (MDA), and conjugated diene (CDE) were quantified. LDL-cholesterol (LDL-C) was calculated for samples with TG ≤4.52 mmol/L

Results: Mean triglycerides, waist and hip circumferences, percentage body fat, subcutaneous fat, and systolic blood pressure increased significantly with increasing body mass index (BMI). In contrast, the mean LDL and TC were higher in underweight than normal weight individuals, and then increased significantly from normal to higher BMI categories. Mean HDL cholesterol significantly decreased with increasing BMI. Overall, CRP, MDA, and CDE were significantly correlated with measures of abdominal obesity. Serum CRP, MDA, and CDE significantly increased in the upper quartiles of waist circumference. Study participants with higher CRP concentrations were more likely to have metabolic syndrome and high oxidative stress markers.

Conclusion: We found a significant positive association between CRP and oxidative stress markers in healthy young people, as well as an increase in these markers in the upper quartiles of waist circumference, but not BMI. Oxidative stress and CRP may interact in the early inflammatory processes of atherosclerosis.

Pro- and Anti-Inflammatory Cytokines in Chronic Pediatric Dialysis Patients: Effect of Aspirin

Dialysis provides effective and safe treatment of ESRD in children, but patients who are maintained on chronic dialysis are at risk for cardiovascular disease. One major risk factor for cardiovascular disease in adult patients with ESRD is chronic inflammation. The effect of anti-inflammatory therapy with aspirin on serum cytokine concentration was studied in seven children who were receiving hemodialysis (HD) and seven who were receiving continuous cycling peritoneal dialysis (CCPD or PD). Dialysis vintage was 4.3 +/- 4.6 yr; single-pool Kt/V was 1.46 +/- 1.4, mean equilibrated Kt/V was 1.27 +/- 0.16, and PD weekly Kt/V was 2.45 +/- 0.30. Baseline proinflammatory cytokine IL-1beta, IL-6, IL-8, and TNF-alpha serum concentrations were significantly elevated, whereas serum anti-inflammatory cytokine IL-4 and IL-10 concentrations were normal. The patterns of cytokine elevation were similar for patients who were receiving HD versus PD. IL-4 and IL-6 concentrations demonstrated strong positive correlation with dialysis vintage (IL-4, P < 0.03; IL-6, P < 0.0001). Pre-aspirin serum cytokine concentrations did not vary with single-pool Kt/V or equilibrated Kt/V for HD patients or with weekly Kt/V for PD patients. Serum IL-8 and TNF-alpha concentrations were significantly reduced by aspirin treatment at 4 mo (P = 0.04 and P = 0.007, respectively). Serum IL-6 concentration decreased with aspirin treatment but not significantly (P = 0.1). Serum IL-1beta concentration remained unchanged, and IL-4 and IL-10 concentrations remained stable throughout aspirin treatment. The effect of aspirin treatment on serum cytokine concentrations was similar for HD and PD patients. In HD patients, IL-6, IL-8, and TNF-alpha remained suppressed 1 mo after discontinuation of aspirin. It is concluded that proinflammatory cytokines are elevated in pediatric HD and PD patients without counterbalance from anti-inflammatory cytokines, and aspirin therapy attenuates inflammation.