Urinary Concentration of Renal Biomarkers in Healthy Term Neonates: Gender Differences in GST-pi Excretion.

BACKGROUND Serum creatinine, the criterion standard in assessment of renal function, is not reliable for the neonatal period because of its dependence on renal immaturity and maternal creatinine levels. Thus, it is important to study other biomarkers of renal function in neonates. The present study aimed to measure the urinary concentration of renal biomarkers: calbindin, clusterin, GST-pi (glutathione-S-transferase-alpha), KIM-1 (kidney injury molecule 1), MCP-1 (monocyte chemoattractant protein-1), and B2M (beta 2-microglobulin) in healthy term neonates. MATERIAL AND METHODS In the study, we included 80 healthy term neonates - 40 females and 40 males. We collected the neonates' urine on their first day of life. Urinary concentrations of calbindin, clusterin, KIM-1, MCP-1, and B2M were assessed using an immunoassay for kidney toxicology research. Because dilution of the urine affects the concentrations of urinary biomarkers, we normalized them to the concentration of urinary creatinine (Cr) and present them as biomarker/Cr ratios. RESULTS We obtained the following values of the assessed biomarker/Cr ratios (median [Q1-Q3]): calbindin/Cr.: 197.04 (56.25-595.17), KIM-1/Cr: 0.09 (0.04-0.18), MCP-1/Cr: 0.05 (0.02-0.14), B2M/Cr: 126.12 (19.03-342.48), GST-pi/Cr in boys: 1.28 (0.46-3.77), GST-pi/Cr in girls: 8.66 (2.51-27.82), clusterin/Cr: 4.55 (1.79-12.97) ng/mg Cr. CONCLUSIONS We showed the urinary levels of calbindin, clusterin, GST-pi, KIM-1, MCP-1, B2M in white, West Slavic, healthy term neonates. We found that in there is an association between female sex and a higher urinary GST-pi excretion, but urinary excretion of calbindin, clusterin, KIM-1, MCP-1, and B2M is sex-independent. The urinary levels of the assessed biomarkers do not depend on the method of delivery.

The Urinary Concentrations of Neutrophil Gelatinase-Associated Lipocalin, Cystatin C and Osteopontin in the Healthy Term and Stable Preterm Neonates: A Pilot Study.

BACKGROUND: In neonates, the assessment of kidney function with serum creatinine is limited; therefore, more effective biomarkers are needed. AIM: The study aimed at analyzing the concentrations of renal biomarkers (osteopontin, cystatin C, and NGAL) in neonates. MATERIAL AND METHODS: The study included 80 term and 20 preterm neonates aged 28-33 weeks of gestation. Biomarkers were measured in urine. Term neonates' urine was collected on the 1st day of life. Preterm neonates' urine was collected on the 1st, 8th, 15th, 22nd day of life. Biomarkers' concentrations were normalized to urinary creatinine (cr.) and presented as urinary biomarker/cr. ratios. RESULTS: Median values of biomarker/creatine ratios in term and preterm neonates were the following: cystatin C/cr.: 7.26 and 439.49; osteopontin/cr.: 135.86 and 1633.37; NGAL/cr. in girls: 212.14 and 256.93; and NGAL/cr. in boys 27.123 and 65.29 ng/mg cr. In preterm neonates the cystatin C/cr. ratio was higher on the 1st than on the 8th day. The osteopontin/cr. ratio did not differ between the days. The NGAL/cr. ratio in girls was higher on the 8th than on the 22nd day, and in boys, the lowest was on the 22nd day. CONCLUSIONS: Prematurity in stable, Caucasian neonates might cause higher osteopontin and cystatin C excretion, but not NGAL. The excretion of NGAL and cystatin C, but not osteopontin, may change during first weeks of premature neonate's life.

The Urinary Concentration of Trefoil Factor 3 (TFF3) in the Term and Preterm Neonates.

BACKGROUND: Distinguishing between a pathologic state and renal development is important in neonatology. Because the assessment of serum creatinine in neonates is not reliable, better biomarkers are needed. Trefoil factor 3 (TFF3) is proposed as a biomarker of kidney injury. The study aimed to assess its urinary concentration in healthy term and stable preterm neonates. MATERIAL AND METHODS: The study included 80 term and 20 preterm neonates born in the Department of Perinatology of the University Clinical Hospital in Bialystok. Urine was obtained from the term neonates on the 1st day of life and from the preterm neonates on the 1st, 8th, 15th and 22nd day of life. The urinary concentration of TFF3 was determined using a commercially available immunoassay and was normalized for the urinary creatinine concentration (cr.). RESULTS: The values of TFF3/cr. were higher in the preterm than in the term neonates (p < 0.05) (median (Q1-Q3): 1486.85 (614.92-3559.18) and 317.29 (68.07-671.40) ng/mg cr.). They did not differ in the subsequent days of the preterm neonates' lives. The ROC curve for TFF3/cr. in the preterm and term neonates showed AUC = 0.751 (cut-off value = 1684.25 ng/mg cr.). CONCLUSIONS: Prematurity is associated with higher urinary excretion of TFF3. Male gender is associated with an increased urinary TFF3 excretion in term neonates.

Protein Biomarkers in Chronic Kidney Disease in Children-What Do We Know So Far?

Chronic kidney disease (CKD) in children is a major concern of medical care and public health as it is related to high morbidity and mortality due to progression to end-stage kidney disease (ESKD). It is essential to identify patients with a risk of developing CKD to implement therapeutic interventions. Unfortunately, conventional markers of CKD, such as serum creatinine, glomerular filtration rate (GFR) and proteinuria, have many limitations in serving as an early and specific diagnostic tool for this condition. Despite the above, they are still the most frequently utilized as we do not have better. Studies from the last decade identified multiple CKD blood and urine protein biomarkers but mostly assessed the adult population. This article outlines some recent achievements and new perspectives in finding a set of protein biomarkers that might improve our ability to prognose CKD progression in children, monitor the response to treatment, or even become a potential therapeutic target.

Causes of Death in Neonates, Infants, Children, and Adolescents at the University Children's Clinical Hospital of Bialystok Between 2018 and 2021.

BACKGROUND Monitoring of mortality rate and causes of death in pediatric hospitals is required in Poland. This study is aimed to evaluate the causes of death in neonates, infants, children, and adolescents obtained from the medical records of the University Children's Clinical Hospital (UCCH) of Bialystok between 2018 and 2021. MATERIAL AND METHODS This was an observational, cross-sectional study. Medical records of 59 patients (12 neonates, 17 infants, 14 children, 16 adolescents) who died in the UCCH of Bialystok in 2018-2021 were analyzed. The records included personal data, medical history, and causes of death. RESULTS Between 2018 and 2021, the leading death causes were congenital malformations, deformations, and chromosomal abnormalities (25.42%, N=15) and conditions originating in the perinatal period (11.86%, N=7). The leading death causes in each age group were: in neonates - congenital malformations, deformations, and chromosomal abnormalities (50%, N=6), in infants -conditions originating in the perinatal period (29.41%, N=5), in children - diseases of the respiratory system (30.77%, N=4), and in teenagers - external causes of morbidity (31%, N=5). Before the COVID-19 pandemic (2018-2019), the leading death causes were congenital malformations, deformations, and chromosomal abnormalities (20.69%, N=6) and conditions originating in the perinatal period (20.69%, N=6). During the COVID-19 pandemic (2020-2021), congenital malformations, deformations, and chromosomal abnormalities (26.67%, N=8) and COVID-19 (10.00%, N=3) were the most common death causes. CONCLUSIONS Leading death causes varied among age groups. The COVID-19 pandemic had an impact on pediatric causes of death and changed their distribution. The results of this analysis should be discussed and conclusions should improve the quality of pediatric care.

Urinary levels of kidney injury molecule-1 (KIM-1) and interleukin-18 (IL-18) in children and adolescents with hyperuricemia.

PURPOSE: Hyperuricemia may lead to silent tissue damage and increase the risk of some diseases, including kidney diseases. Increased serum uric acid concentration induces inflammatory pathways and promotes kidney damage. This study aimed to determine whether hyperuricemia influences the levels of urinary kidney injury markers in children and adolescents with hyperuricemia, assessed by the urinary concentrations of interleukin-18, a biomarker of inflammation, and kidney injury molecule-1 (KIM-1), a biomarker of kidney injury. MATERIAL AND METHODS: The study included 73 children and adolescents (32 males and 41 females) aged 2-18 years. They were divided into two groups: hyperuricemia (HU) group (n â€‹= â€‹48) and normouricemia - reference group (R) (n â€‹= â€‹25). The concentrations of urinary interleukin-18 and KIM-1 were measured using an ELISA kit and were normalized for urinary creatinine (cr.) concentration. RESULTS: The median interleukin-18/cr. Levels in the HU group were significantly higher than in the R group (median, Q1-Q3) 21.83 (11.32-35.96) and 12.68 (7.11-24.04), respectively, (p â€‹< â€‹0.05). The KIM-1/cr. in the HU group and the R group were (median, Q1-Q3) 0.79 (0.45-1.03) and 0.81 (0.59-1.01), respectively, and the difference was not significant. KIM-1/cr. did not differ between the groups. Interleukin-18/cr. ratio correlated positively with serum uric acid concentration (r â€‹= â€‹0.24, p â€‹< â€‹0.05). CONCLUSIONS: Interleukin-18/cr., but not KIM-1/cr. was higher in children with hyperuricemia. Hyperuricemia results in increased IL-18 in urine, in absence of other markers of kidney injury, suggesting inflammation in the kidney. Additional studies on the adults should be done, to confirm this hypothesis.

Urinary Levels of Cathepsin B in Preterm Newborns.

Increased investment in perinatal health in developing countries has improved the survival of preterm newborns, but their significant multiorgan immaturity is associated with short and long-term adverse consequences. Cathepsin B, as a protease with angiogenic properties, may be related to the process of nephrogenesis. A total of 88 neonates (60 premature children, 28 healthy term children) were included in this prospective study. We collected urine samples on the first or second day of life. In order to determine the concentration of cathepsin B in the urine, the commercially available enzyme immunoassay was used. The urinary concentrations of cathepsin B normalized with the urinary concentrations of creatinine (cathepsin B/Cr.) in newborns born at 30-34, 35-36, and 37-41 (the control group) weeks of pregnancy were (median, Q1-Q3) 4.00 (2.82-5.12), 3.07 (1.95-3.90), and 2.51 (2.00-3.48) ng/mg Cr, respectively. Statistically significant differences were found between the group of newborns born at 30-34 weeks of pregnancy and the control group (p < 0.01), and between early and late preterm babies (PTB) (p < 0.05). The group of children born at 35-36 weeks of pregnancy and the control group did not differ significantly. This result suggests that the elevated urinary cathepsin B/Cr. level may be the result of the kidneys' immaturity in preterm newborns.

Is Urinary Netrin-1 a Good Marker of Tubular Damage in Preterm Newborns?

There is a lack of a good marker for early kidney injury in premature newborns. In recent publications, netrin-1 seems to be a promising biomarker of kidney damage in different pathological states. The study aimed to measure the urinary level of netrin-1 depending on gestational age. A prospective study involved 88 newborns (I-60 premature newborns, II-28 healthy term newborns). Additionally, premature babies were divided for 2 groups: IA-28 babies born between 30-34 weeks of gestation and IB-32 born at 35-36 weeks. The median urinary concentration of netrin-1 was: IA-(median, Q1-Q3) 63.65 (56.57-79.92) pg/dL, IB-61.90 (58.84-67.17) pg/dL, and II-60.37 (53.77-68.75) pg/dL, respectively. However urinary netrin-1 normalized by urinary concentration of creatinine were IA-547.9 (360.2-687.5) ng/mg cr., IB-163.64 (119.15-295.96) ng/mg cr., and II-81.37 (56.84-138.58) ng/mg cr., respectively and differ significantly between the examined groups (p = 0.00). The netrin-1/creatinine ratio is increased in premature babies. Further studies examining the potential factors influencing kidney function are necessary to confirm its potential value in the diagnosis of subclinical kidney damage in premature newborns.

Urinary netrin-1 concentration in healthy full-term newborns.

INTRODUCTION: Monitoring of renal function in acute kidney injury in the pediatric population is complicated by the lack of age-related reference values of new biomarkers. Urinary netrin-1 is a new marker to demonstrate early kidney damage. Netrin-1 has a molecular mass of 72 kDa. It is therefore unlikely that it is filtered by the glomerulus under normal conditions. However, netrin-1 is highly induced after acute and chronic kidney injury and excreted in urine in humans. The aim of the study was to determine the normal concentrations of urinary netrin-1 in healthy full-term newborns. MATERIAL AND METHODS: The study included 88 healthy full-term neonates (51 boys and 37 girls) born from normal, uncomplicated pregnancies. The concentration of netrin-1 was determined in urine obtained on the first or second day of life with a commercially available ELISA kit. RESULTS: The urinary concentration of netrin-1 in newborns was independent of gender and time of urine collection. We found a negative correlation between both the urinary netrin-1 concentration and urinary netrin-1 concentration after normalization for urinary creatinine and the birth weight. CONCLUSIONS: This is the first study showing the urinary netrin-1 concentration in healthy full-term newborns. Future investigation is needed to confirm its potential role as a marker of kidney function in this age group.

Dispersive liquid-liquid microextraction coupled to liquid chromatography tandem mass spectrometry for the determination of phenolic compounds in human milk.

This work describes a novel approach for the analysis of 11 phenolic compounds (naringenin, hesperetin, kaempferol, quercetin, epicatechin, epicatechin gallate, epigallocatechin gallate, genistein, daidzein, caffeic acid, gallic acid) in human milk. Clean-up of the sample and extraction of 11 analytes from milk was performed by dispersive liquid-liquid microextraction (DLLME). Under the optimal conditions, the extraction recoveries of 11 analytes were in a range from 94.3% to 108%. For determination of phenolic compounds in extracts, LC-ESI-MS/MS method was used. The calibration curves showed linearity in the concentration ranges from 0.01 to 1500 ng mL-1 and the limits of detection were in a range from 0.18 ng L-1 to 74 ng mL-1. The repeatability and intermediate precision expressed as the relative standard deviations were below 7.6% and 9.9%, respectively. The DLLME-LC-ESI-MS/MS method was successfully applied to the determination of phenolic compounds present in breast milk.

Tubular and Glomerular Biomarkers of Acute Kidney Injury in Newborns.

BACKGROUND: Acute Kidney Injury (AKI) is a sudden decrease in kidney function. In the early period, the highest percentage of AKI occurs among newborns hospitalized in the neonatal intensive care units, especially premature neonates. The prognosis of AKI depends on the type and severity of the cause of an injury, the accuracy and the time of diagnosis and treatment. The concentration of serum creatinine is still the main diagnostic test, although it changes in the course of AKI later than glomerular filtration rate GFR. In addition, the reliability of the determination of creatinine level is limited because it depends on many factors. New studies have presented other, more useful laboratory markers of renal function that can be measured in serum and/or in urine. OBJECTIVE: The aim of the work was to present the latest data about tubular and glomerular biomarkers of acute kidney injury in newborns. METHODS: We undertook a structured search of bibliographic databases for peer-reviewed research literature by using focused review topics. According to the conceptual framework, the main idea of research literature has been summarized and presented in this study. RESULTS: The concentrations of some novel biomarkers are higher in serum and/or urine of term and preterm newborns with AKI, especially in the course of perinatal asphyxia. CONCLUSION: In this systematic review of the literature, we have highlighted the usefulness of biomarkers in predicting tubular and/or glomerular injury in newborns. However, novel biomarkers need to prove their clinical applicability, accuracy, and cost-effectiveness prior to their implementation in clinical practice.

The Tubular Damage Markers: Neutrophil Gelatinase-Associated Lipocalin and Kidney Injury Molecule-1 in Newborns with Intrauterine Growth Restriction.

BACKGROUND: Intrauterine growth restriction (IUGR) is a poorly understood complication of pregnancy. It may be associated with various diseases in adulthood, such as hypertension, cardiovascular disease, insulin resistance, and end-stage renal disease. OBJECTIVES: The aim of this study was to check whether IUGR affects the function of renal tubules, as assessed by the tubular damage markers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (KIM-1). METHODS: The study included 126 term neonates. Thirty-eight newborns were the result of pregnancies complicated by IUGR. Eighty-eight healthy newborns were the result of normal pregnancies with no prenatal or perinatal complications. The concentrations of urinary NGAL and KIM-1 were determined with a commercially available ELISA kit and were normalized for urinary creatinine (Cr) concentration. RESULTS: We found a significantly higher urinary concentration of NGAL and NGAL/Cr ratio in newborns from pregnancies complicated by IUGR when compared to the reference group. We found that female gender was associated with a higher concentration of urinary NGAL and also urinary NGAL/Cr. CONCLUSIONS: This is the first work that demonstrates that urinary NGAL concentration and urinary NGAL/Cr are significantly higher in infants that are small for gestational age than in appropriate-for-gestational-age infants. This might indicate subclinical kidney damage in newborns with IUGR.

Reference Data on Neonatal Serum N-Acetyl-ß-hexosaminidase Activity.

BACKGROUND: Determination of neonate serum's N-acetyl-ß-hexosaminidase (HEX) activity and correlation results with Apgar scale and factors routinely determined in newborn serum. AIMS: Providing reference values of neonates serum HEX activities, and indicate their diagnostic significance. STUDY DESIGN: The study was performed using random serum samples of 111 infants (53 ♂/58 ♀), aged 1-30 days. The activity of HEX was determined colorimetrically and expressed in nKat/L. RESULTS: Serum HEX activity of 111 newborns was 360.5 ± 114.0 nKat/L and significantly positively correlated with gestation week at the day of delivery, birth weight, weight on day of blood collection, sex, and serum CRP. CONCLUSIONS: Reference values presented for neonatal serum activities of HEX may be used in neonatal diagnostics, for example, to detect inflammation and other diseases or for early assessment of the risk of Tay-Sachs and Sandhoff diseases.

Health term-born girls had higher levels of urine neutrophil gelatinase-associated lipocalin than boys during the first postnatal days.

UNLABELLED: Neutrophil gelatinase-associated lipocalin (NGAL) is one of the most extensively examined biological markers for early prediction of acute kidney injury, but there is a lack of data on normal NGAL values in healthy term-born infants. This encouraged us to established serum and urine levels using samples collected from 38 girls and 50 boys, born at a median age of 39 weeks, during the first 48 hours after birth. CONCLUSION: Our findings showed that urine NGAL, but not serum levels, were significantly higher in girls than in boys.

Effects of erythropoietin on ICAM-1 and PECAM-1 expressions on human umbilical vein endothelial cells subjected to oxidative stress.

The protective effect of erythropoietin (Epo) is based on its ability to reduce oxidation and to stabilize the cells. The aim of the study was to evaluate the influence of Epo on malonyl dialdehyde (MDA), intercellular adhesion molecule-1 (ICAM-1) (CD54) and platelet-endothelial cell adhesion molecule-1 (PECAM-1) (CD31) levels on human umbilical vein endothelial cells (HUVECs) stimulated by tumour necrosis factor-α (TNF-α). HUVECs were incubated with Epo (10-40 IU ml⁻¹) or TNF-α (10-40 ng ml⁻¹) alone or preincubated with Epo (20 IU ml⁻¹) and subsequently stimulated with TNF-α (10-40 ng ml⁻¹). MDA concentrations were measured using the high-performance liquid chromatography, whereas ICAM-1 and PECAM-1 expressions were evaluated by flow cytometry. Incubation with Epo resulted in a decrease in MDA and the increased expressions of ICAM-1 and PECAM-1. Exposure to TNF-α reflected an increase in MDA, ICAM-1 and PECAM-1 levels. These changes were inhibited by preincubation with Epo. The cytoprotective activity proven in this study points to new applications and therapeutic possibilities for Epo.

[Cytoprotection--protective agents and mechanisms of their activity in the cell]. / Cytoprotekcja--czynniki ochronne i mechanizmy ich dzialania w komórce.

Cytoprotection can be defined as the ability to protect cells against wide variety of damaging agents. A series of recent studies indicate that many substances participate in this process. It has been proved that different mechanisms as inhibition of oxidative stress or apoptosis mediate in cytoprotection. However, a number of mechanisms responsible for this extremely compound process remain still unknown. In this revew we discuss the scientific evidence documenting cytoprotective agents and pathways of their activity.

[The prolipherative and proapoptotic activity of limfoid nodules cells in the hypertrophic pharyngeal tonsil]. / Aktywnosc proliferacyjna i proapoptotyczna komórek limfoidalnych grudek chlonnych przerosnietego migdalka gardlowego.

UNLABELLED: The human immune system recognize and eliminate strange antigens by present of lymphoid cell clones, which to come into being in consequence of clonal proliferation inducted by contact with the antigen. The cell clones to be due to the somatic mutations and recognize antigens incorrectly are eliminate by apoptosis. THE AIM OF THE STUDY: To estimation of expression of chosen proliferative and proapoptotic proteins in lymphoid follicles and extra-follicular region of pharyngeal tonsil. MATERIAL AND METHODS: Histochemical examination of chosen proapoptotic (p53, Bax) and proliferative (Ki-67, PCNA) proteins in adenoidectomised pharyngeal tonsil was done. RESULTS: The most greater proliferation activity was in the germinal centers of lymphoid follicles, much less in the mantle zone and in the extrafollicular region. Similarly, maximal expression of proapoptotic proteins was in germinal centers of tonsil lymphoid follicles, the least in the mantle zone. CONCLUSIONS: The high proliferative and proapoptotic activity of lymphoid follicles germinal centers to bear evidence of clonal selection of undistinguished lymphoid cells to come into being by somatic mutations.

[The influence of erythropoietin (Epo) on intercellular adhesion molecule-1 (ICAM-1, CD54) and platelet-endothelial cell adhesion molecule-1 (PECAM-1, CD31) expression on human umbilical vein endothelial cells (HUVEC) induced by tumor necrosis factor-alpha (TNF-alpha)]. / Wplyw erytropoetyny (Epo) na indukowana czynnikiem martwicy nowotworów-alpa (tnf-alpha) ekspresje czasteczek adhezji miedzykomórkowej-1 (ICAM-1, CD54) i czasteczek adhezji komórkowej plytek i sródblonka-1 (PECAM-1, CD31) na powierzchni komórek sródblonka ludzkiej zyly pepowinowej (HUVEC).

UNLABELLED: The latest research proved that erythropoietin (Epo), a sensitive to hypoxia physiological erythropoiesis regulator, used successfully to treat anemia, displays cytoprotective, angiogenic, anti-inflammatory, anti-oxidative and anti-apoptotic properties. The aim of the study was to examine the influence of Epo on intercellular adhesion molecule-1 (ICAM-1) and platelet-endothelial cell adhesion molecule-1 (PECAM--1) expression on human umbilical vein endothelial cells (HUVEC) induced by tumor necrosis factor-a (TNF-alpha). MATERIAL AND METHODS: Human umbilical vein endothelial cells were cultured in a standard medium (M 199). The experiment was performed five times on the forth passage of HUVEC culture. For stimulation TNF-alpha was used in concentrations: 10, 20, 40 ng/ml (6 hours) and Epo in concentrations: 10, 20, 40 IU/ml (24 hours). The expression level of ICAM-1 and PECAM-1 on HUVEC were quantified by flow cytometry. RESULTS: The Incubation of HUVEC with TNF-a significantly increased the ICAM-1 and PECAM-I expression. The cultures pretreated with Epo reduced ICAM-1 and PECAM-I expression induced by TNF-a from 70.0 +/- 3.94% to 59.3 +/- 0.60% and from 83.4 +/- 2.27% to 57.7 +/- 0.66% respectively for ICAM-1 and PECAM-1. CONCLUSIONS: Erythropoietin statistically significantly decreases ICAM-1 and PECAM-1 expression on HUVEC stimulated by TNF-alpha.

[The influence of hyperglycemia on oxidation-reduction reaction of human umbilical vein endothelial cells]. / Wplyw hiperglikemii na procesy oksydacyjno-redukcyjne w komórkach srodblonka ludzkiej zyly pepowinowej.

UNLABELLED: Hyperglicemia is recognised as a primal factor responsible for microcirculatory changes in diabetic patients. There exist many reasons to claim that high glucose concentrations, generating reactive oxygen species (ROS), induce oxidative stress which initiates peroxidation processes. The end products of lipids peroxidation (aldehydes) cause disturbances of cellular membrane structures, its depolarization, inhibition of membrane's enzymes activity, indicating loss of cellular membrane integrity and uncoupling of oxidative phosphorylation in mitochondria. AIM OF THIS STUDY was to assess the influence of hyperglycemia on oxidation-reduction reaction of human umbilical vein endothelial cells, by determining malonyldialdehyde (MDA) content, a lipids peroxidation marker. MATERIAL AND METHODS: Human umbilical vein endothelial cells were cultured in a standard medium (M 199). The experiment was performed five times on forth passage of HUVEC culture. The cultures were incubated for 48 hours with glucose in concentrations 5.5; 11.1 and 22.2 mmol/l. In the HUVEC lysate malonyldialdehyde (MDA) concentration was measured by HPLC method. RESULTS: It was proved that MDA content in the control culture cells (5.5 mmol/l of glucose) was 15.1 +/- 1.6 nmol/mg protein. In the conditions of hyperglycemia (11.1 and 22.2 mmol/l) MDA content increased (respectively: 18.1 +/- 1.3 and 21.5 +/- 2.5 nmol/mg protein) and the differences were statistically significant (p<0.05). CONCLUSIONS: Hyperglycemia disturbs normal oxidation-reduction reaction of human umbilical vein endothelial cells inducing oxidative stress.

[Erythropoietin prevents oxidative stress and lipid peroxidation process in human umbilical vein endothelial cells induced by tumor necrosis factor alpha]. / Erytropoetyna zapobiega stresowi oksydacyjnemu indukowanemu czynnikiem martwicy nowotworów alpha oraz procesowi peroksydacji lipidów w komórkach sródblonka naczyn zylnych ludzkiej pepowiny.

UNLABELLED: According last research erythropoietin (Epo), glycoprotein known as a physiological regulator of erythropoiesis and used successfully to treat anemia, displays cytoprotective properties. It is supposed that the protective effect of EPO is based on its ability to oxidation-reduction stabilization of cells. AIM: The aim of the study was to examine the influence of oxidative stress and lipid peroxidation in human umbilical vein endothelial cells (HUVEC) induced by tumor necrosis factor-alpha (TNF-alpha). MATERIAL AND METHODS: Human umbilical vein endothelial cells were cultured in a standard medium (M 199). The experiment was performed five times on the forth passage of HUVEC culture. For stimulation TNF-alpha was used in concentrations: 10, 20, 40 ng/ml (6 hours) and erythropoietin in concentrations: 10, 20, 40 IU/ml (24 hours). In the HUVEC lysate malonyldialdehyde (MDA), lipid hydroperoxides and reduction gluthation (GSH) concentrations were measured by HPLC method. RESULTS: MDA concentration statistically significantly decreased from 16.48 +/- 1.21 to 14.40 +/- 0.72 nmol/mg protein and LOOH concentration from 73.00 +/- 5.44 do 68.86 +/- 1.89 nmol/mg protein in the cell's lysate due to the preincubation with Epo of HUVEC cells, stimulated with TNF-alpha. MDA and LOOH concentrations in the control culture were 12.91 +/- 1.02 nmol/mg protein and 57.80 +/- 6.16 nmol/mg protein respectively. The application of erythropoietin while the cells were being stimulated with TNF-alpha prevented the decrease in GSH concentration which was 34.77 +/- 0.70 nmol/mg protein in the control culture, 33.11 +/- 1.65 nmol/mg protein in the culture stimulated with TNF-alpha and 34.17 +/- 0.14 nmol/mg protein in culture preincubated with Epo and stimulated by TNF-alpha. CONCLUSIONS: Erythropoietin (Epo) prevents oxidative stress and lipid peroxidation process in human umbilical vein endothelial cells (HUVEC) induced by tumor necrosis factor-alpha.