Joanna Bober

Publications of Joanna Bober

• Conjugated linoleic acid isomers may diminish human macrophages adhesion to endothelial surface.

  Authors: Ewa Stachowska, Aldona Siennicka, Magdalena Baśkiewcz-Hałasa, Joanna Bober, Boguslaw Machalinski, Dariusz Chlubek

  International journal of food sciences and nutrition. 07/2011; 63(1):30-5.

  Dysfunction of endothelial cells and activation of monocytes in the vascular wall are important pathogenetic factors of atherosclerosis. Conjugated linoleic acids (CLAs) can modulate the function ofDysfunction of endothelial cells and activation of monocytes in the vascular wall are important pathogenetic factors of atherosclerosis. Conjugated linoleic acids (CLAs) can modulate the function of immune system in humans: reduce the concentration of atherogenic lipoproteins, and the intensity of inflammatory processes in the plasma. In this paper, we focus on macrophage's surface integrins (β1 integrin CD49d/CD29-(VLA4); Mac-1 as well as endothelial human vein endothelial cell (HUVEC) surface adhesins: vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1)) expression in relation to CLA isomer used during cell culture. Both CLA isomers decreased expression of VLA-4 and Mac-1 on macrophages compared with control cells (cultured with bovine serum albumine (BSA) or oxidized form of low-density lipoproteins). cis-9, trans-11 CLA isomer reduced ICAM-1 and VCAM-1 expression on the endothelium surface. Strong tendency to reduce of adhesion of macrophages to HUVEC in the cells cultured with CLA isomers was observed. The potential role of cis-9, trans-11 CLA in the reduction of adhesion of macrophages to the HUVEC--one of the important steps in the inflammatory process, can be considerate. These mechanisms may contribute to the potent anti-atherosclerotic effects of CLA in vivo.

• [Metformin - mechanisms of action and use for the treatment of type 2 diabetes mellitus].

  Authors: Marzena Grzybowska, Joanna Bober, Maria Olszewska

  Postȩpy higieny i medycyny doświadczalnej (Online). 01/2011; 65:277-85.

  Metformin is widely used for the treatment of type 2 diabetes mellitus. Although this biguanide derivative has been used for more than 50 years, its mechanism of action has not been fully elucidated.Metformin is widely used for the treatment of type 2 diabetes mellitus. Although this biguanide derivative has been used for more than 50 years, its mechanism of action has not been fully elucidated. In this article we describe the latest achievements concerning the mechanisms of antihyperglycemic action of metformin. They include: decrease of glucose absorption in the small intestine, increase of glucose transport into cells, decrease in the plasma free fatty acid concentrations and inhibition of gluconeogenesis. Activation of AMP-activated protein kinase (AMPK) plays an important role in these processes. The latest discoveries have revealed mechanisms of anti-atherosclerotic, hypotensive and anticancer action of metformin and its impact on vein endothelial function. The pleiotropic actions of metformin include impact on plasma lipid profile, decrease of oxidative stress, and increase in plasma fibrinolytic activity. Although metformin is not metabolized, the latest research has shown that it is actively transported into hepatocytes and renal tubular epithelium, by OCT1 (organic cation transporter 1, encoded by the SLC22A1 gene) and OCT2 (organic cation transporter 2, encoded by the SLC22A2 gene), respectively. However, MATE1 transporter (multidrug and toxin extrusion 1 protein) is encoded by the SLC47A1 gene and facilitates metformin excretion from these cells into bile and urine. Metformin transporter gene polymorphisms may contribute to significant variation in drug response. Further studies of mechanisms of metformin action could contribute to its wider use for the prevention of type 2 diabetes mellitus, cancer, and Alzheimer’s disease, and for the treatment of type 1 diabetes mellitus, and polycystic ovary syndrome (PCOS).

• Urinary hepatocyte growth factor indicates ischemia/reperfusion injury after kidney transplantation.

  Authors: Ewa Kwiatkowska, Karolina Kędzierska, Joanna Bober, Barbara Dołęgowska, Violetta Dziedziejko, Edyta Gołembiewska, Kazimierz Ciechanowski, Magdalena Wiśniewska

  Polskie Archiwum Medycyny Wewnętrznej. 11/2010; 120(11):437-42.

  Despite the development of immunosuppressive regimens in kidney transplantation, long-term graft survival rates have not increased significantly. One of the causes of long-term graft loss isDespite the development of immunosuppressive regimens in kidney transplantation, long-term graft survival rates have not increased significantly. One of the causes of long-term graft loss is ischemia-reperfusion insult. Hepatocyte growth factor (HGF) is a regenerative factor produced in response to injury. Our aim was to assess the effect of HGF and xanthine oxidase (indicators of ischemia/reperfusion insult) on early and late kidney function. In 17 patients, HGF levels in urine and xanthine oxidase activity in blood were examined 1, 7, 14, 30 days, 3 and 6 months after kidney transplantation. We also measured 24-hour diuresis and serum creatinine levels after transplantation. Urinary HGF levels were highest 1 day after transplantation. During the following week, it rapidly decreased and was maintained at similar levels in the later period. Creatinine at 1 day showed a positive correlation with urinary HGF levels at 1 day and at 3 months (R = 0.54, P <0.05 and R = 0.82, P <0.01, respectively). Creatinine at 7 days positively correlated with HGF levels at 6 months (R = 0.82, P <0.05). HGF levels at 1 day and at 6 months positively correlated with xanthine oxidase activity at 1 day (R = 0.73, P <0.001 and R = 0.77, P <0.02, respectively). A negative correlation was observed between HGF levels at 6 months and diuresis 1 and 7 days after transplantation (R = -0.99, P <0.00 001 and R = -0.77, P <0.05, respectively). Urinary HGF is a good marker of perioperative kidney damage and may affect long-term graft function.

• [Oxidation stress in inflammatory bowel disease].

  Authors: Mariusz Molenda, Joanna Bober

  Annales Academiae Medicae Stetinensis. 01/2010; 56(2):28-32.

  Inflammatory bowel disease (Crohn's disease and ulcerative colitis) has a complex and still largely unknown etiopathology. One of the possible causes can be traced to free radical reactions, andInflammatory bowel disease (Crohn's disease and ulcerative colitis) has a complex and still largely unknown etiopathology. One of the possible causes can be traced to free radical reactions, and precisely to disorders in the equilibrium between pro-oxidants and antioxidants. This article is a concise review of the literature showing the current state of knowledge of interactions between pro-oxidants and antioxidants in Crohn's disease and ulcerative colitis.

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• Does oxidative stress affect the activity of the sodium-proton exchanger?

  Authors: Joanna Bober, Karolina Kedzierska, Ewa Kwiatkowska, Ewa Stachowska, Edyta Gołembiewska, Olech Mazur, Zdzisław Staniewicz, Kazimierz Ciechanowski, Dariusz Chlubek

  Annales Academiae Medicae Stetinensis. 01/2010; 56(3):5-12.

  Accumulation of reactive oxygen species (ROS) takes place in patients with chronic renal failure (CRF). Oxidative stress causes disorders in the activity of the sodium-proton exchanger (NHE). StudiesAccumulation of reactive oxygen species (ROS) takes place in patients with chronic renal failure (CRF). Oxidative stress causes disorders in the activity of the sodium-proton exchanger (NHE). Studies on NHE in CRF produced results that are discrepant and difficult to interpret. The aim of this study was to demonstrate that oxidative stress had an effect on the activity of NHE. We enrolled 87 subjects divided into 4 groups: patients with CRF treated conservatively; patients with CRF hemodialyzed without glucose--HD-g(-); patients with CRF hemodialyzed with glucose--HD-g(+); controls (C). The activity of NHE, the rate of proton efflux V(max), Michaelis constant (Km), and the concentration of thiobarbituric acid-reactive substances (TBARS, an indicator of oxidative stress) in plasma, as well as the concentration of reduced glutathione in blood were determined. The concentration of TBARS was significantly higher in hemodialyzed patients before and after dialysis and in patients with CRF on conservative treatment in comparison with group C. TBARS in plasma correlated negatively with VpH(i)6.4 in group C and with V(max) and VpH(i)6.4 after HD in group HD-g(-). We found that the concentration of creatinine correlated with TBARS (p < 0.0001; r = +0.51) in the conservatively treated group. We observed a marked oxidative stress and decreased NHE activity when dialysis was done without glucose, whereas patients dialyzed with glucose demonstrated a relatively low intensity of oxidative stress.

• [Cigarette smoking as a promoting factor for nonspecific inflammatory bowel disease].

  Authors: Mariusz Molenda, Joanna Bober, Dobrosława Stańkowska-Walczak, Małgorzata Stańczyk-Dunaj

  Annales Academiae Medicae Stetinensis. 01/2010; 56(3):50-4.

  Nonspecific inflammatory bowel diseases represent serious and chronic pathologies of the gastrointestinal tract. Even though the etiology of these diseases has not been fully elucidated, it is knownNonspecific inflammatory bowel diseases represent serious and chronic pathologies of the gastrointestinal tract. Even though the etiology of these diseases has not been fully elucidated, it is known that environmental factors like cigarette smoking may induce and exacerbate their course. Many substances in cigarette smoke have a modulatory effect on the immune system through a change in the composition of pro-/anti-inflammatory cytokines witch plays its part in the development of inflammation. Moreover, cigarette smoke contains reactive oxygen species which may combine with decreased activity of antioxidant enzymes to produce an additional proinflammatory effect. It is interesting that cigarette smoke has a different effect on the course of Crohn's disease compared with ulcerative colitis.

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• [Characteristics of sodium-proton antiporter of human blood-platelets]

  Authors: Magdalena Gassowska, Joanna Bober, Dariusz Chlubek

  Annales Academiae Medicae Stetinensis. 02/2008; 54(2):7-13.

  The aim of this work was characteristics of Na+/H+ sodium-proton exchanger. The structure, significance and biochemical properties of NHE proteins have been presented. A review of literature onThe aim of this work was characteristics of Na+/H+ sodium-proton exchanger. The structure, significance and biochemical properties of NHE proteins have been presented. A review of literature on involving NHE in the process of human blood platelets activation has been carried out in the work. Factors causing activation as well as inhibition of NHE have also been discussed.

• [Oxidative stress and trace elements affect the activity of sodium transporting systems in a cellular membrane of a erythrocyte]

  Authors: Karolina Kedzierska, Joanna Bober, Ewa Kwiatkowska, Ewa Stachowska, Maria Olszewska, Dariusz Chlubek, Kazimierz Ciechanowski

  Annales Academiae Medicae Stetinensis. 01/2008; 54(3):105-14.

  We examined the activity of sodium transporting systems (STS) in a cellular membrane of erythrocytes in a group of 21 patients under chronic hemodialysis treatment with the dialyzing fluid containingWe examined the activity of sodium transporting systems (STS) in a cellular membrane of erythrocytes in a group of 21 patients under chronic hemodialysis treatment with the dialyzing fluid containing glucose HD-g(+), and 22 patients dialysed with the fluid not containing glucose HD-g(-), 21 patients with chronic kidney failure already not treated with dialysis and 21 control group. We examined the concentration of antioxidative system cofactors, such as zinc, copper and selenium in erythrocytes and plasma. The marker of oxidative stress in erythrocytes and plasma was the concentration of TBARS. Among all STS we examined the activity of Na(+)/K(+) ATP-ase, Na(+)/K(+)/Cl(-); co-transport, Na(+)/Li(+) exchanger, Na(+), K(+)-outflow. Copper zinc and selenium as cofactors of antioxidative enzymes may reflect the antioxidative processes inside the organism undergoing the influence of free radicals.

• Conjugated linoleic acids can change phagocytosis of human monocytes/macrophages by reduction in Cox-2 expression.

  Authors: Ewa Stachowska, Magdalena Baśkiewicz-Masiuk, Violetta Dziedziejko, Grazyna Adler, Joanna Bober, Bogusław Machaliński, Dariusz Chlubek

  Lipids. 09/2007; 42(8):707-16.

  Prostaglandin E2 produced endogenously (by cyclooxygenases) can regulate macrophage phagocytosis. Cyclooxygenase activity reduction (mainly through inhibition of inducible Cox-2) can induce PGE2Prostaglandin E2 produced endogenously (by cyclooxygenases) can regulate macrophage phagocytosis. Cyclooxygenase activity reduction (mainly through inhibition of inducible Cox-2) can induce PGE2 synthesis depression and can activate the phagocytosis process. There are no reports in the literature explaining whether conjugated linoleic acid dienes (trans-10, cis-12 CLA and cis-9, trans-11 CLA) modify the phagocytic activity of human macrophages. For the purpose of this study, monocytes were isolated from venous blood, incubated for 7 days with 30 microM CLAs, and then (in some experiments) LPS (1 microg/mL) was added to the medium. Subsequently, monocyte/macrophage phagocytosis, NF-kappaB transcription factor activity, Cox-2 and PPARgamma mRNA expression (and the amounts of Cox-2 and PPARgamma proteins) and PGE2 synthesis were determined. Both CLA isomers increased macrophage phagocytosis through inhibition of Cox-2 expression (might by inactivation the NF-kappaB pathway). The inhibition of mRNA Cox-2 expression contributed (particularly with respect to trans-10, cis-12 CLA) to a decrease in protein Cox-2 synthesis and to reduction of prostaglandin E2 content in the cell. The inhibition of PGE2 synthesis (by CLA treatment) enhanced the phagocytosis process in macrophages.

• Influence of glucose in the dialysate on the activity of erythrocyte-glutathione-peroxidase and blood selenium concentration in hemodialyzed patients.

  Authors: Joanna Bober, Ewa Kwiatkowska, Karolina Kedzierska, Maria Olszewska, Edyta Gołebiewska, Ewa Stachowska, Elzbieta Kucharska, Kazimierz Ciechanowski, Dariusz Chlubek

  Archives of medical research. 05/2007; 38(3):330-6.

  BACKGROUND: The aim of the study was to show the influence of glucose in the dialysate on the intensity of oxidative stress, activity of glutathione peroxidase (GSHPx) and concentration of seleniumBACKGROUND: The aim of the study was to show the influence of glucose in the dialysate on the intensity of oxidative stress, activity of glutathione peroxidase (GSHPx) and concentration of selenium in patients undergoing regular hemodialysis. METHODS: The study was comprised of 85 patients hemodialyzed with dialysate containing glucose [HD-g(+)] or not containing glucose [HD-g(-)], patients with chronic renal failure on conservative treatment and control group. The concentrations of the products of reaction with thiobarbituric acid (TBARS), concentration of selenium in erythrocytes and plasma, concentration of copper in erythrocytes and the activity of GSHPx were determined. RESULTS: GSHPx had significantly higher activity in HD-g(-) group before HD than in control group. In HD-g(+) group before hemodialysis, the activity of GSHPx was significantly lower than in the control group. After HD, the activity showed a statistically significant increase. In both hemodialyzed groups, selenium concentration before hemodialysis both in plasma and erythrocytes was significantly lower, compared to control group. In the group of patients with CRF on conservative treatment, selenium concentration in RBC was significantly higher, compared to concentrations obtained in other groups except for control group. The increase of copper concentration in erythrocytes was accompanied by the increase of oxidative stress and increase of TBARS concentration. The opposite relationship was observed for selenium-its concentration was inversely correlated to copper concentration. CONCLUSIONS: In both groups of hemodialyzed patients, hemodialysis caused the increase of GSHPx in erythrocyte activity and increase of plasma and erythrocyte selenium concentration.

• Effect of hemodialysis on the content of fatty acids in monolayers of erythrocyte membranes in patients with chronic renal failure.

  Authors: Barbara Dolegowska, Ewa Kwiatkowska, Teresa Wesolowska, Joanna Bober, Dariusz Chlubek, Kazimierz Ciechanowski

  Renal failure. 02/2007; 29(4):447-52.

  Lipid metabolism disorders are found in patients with chronic renal failure (CRF). Changes in the content of fatty acids of the phospholipid fraction of erythrocyte membranes can lead to changes inLipid metabolism disorders are found in patients with chronic renal failure (CRF). Changes in the content of fatty acids of the phospholipid fraction of erythrocyte membranes can lead to changes in the rheological properties. The objective of our study was to assess the effect of hemodialysis on the composition of fatty acids in two fractions of phospholipids: sphingomyelin (SPH, representative of the external monolayer) and phosphatidylethanolamine (PE, representative of the internal monolayer). Venous blood was drawn from patient with CRF before and after the HD procedure. Lipids from the erythrocyte stroma were extracted using the Rose and Oklander method and then were separated into phospholipid fractions using thin-layer chromatography (TLC). PE and SPH fractions were extracted, and the fatty acid profile was determined using gas chromatography (Perkin Elmer 8400; RTx 2330 column; length: 105 m). In the phospholipid fractions tested, a high content of saturated FA with a medium carbon chain (C 16:0 to C 18:2) and a long carbon chain such as C 24:0, C 24:1; C 22:6; and C 26:0 was found. The HD procedure affected the FA profile in the fractions tested. The proportion of saturated and unsaturated long-chain FA (above 18 C) increased in PE. However, the content of medium-chain FA C 16:0 to C 18:1 decreased. A significant decrease in the content of the majority of long-chain FA could be noted in SPH. The ratio of unsaturated (U) to saturated (S) fatty acids in the SPH fraction increased. Hemodialysis has a significant effect on the content of fatty acids in the PE and SPH fractions of erythrocyte membranes in patients with CRF.

• [Changes in the lipid content of erythrocytes in patients with chronic renal failure]

  Authors: Justyna Witkowska, Joanna Bober, Dariusz Chlubek

  Annales Academiae Medicae Stetinensis. 02/2007; 53(2):46-51.

  The oxidative stress accompanying chronic renal failure may cause a number of harmful changes in the organism of a human being. Hemodialysis, as one of the treatment methods of chronic renal failure,The oxidative stress accompanying chronic renal failure may cause a number of harmful changes in the organism of a human being. Hemodialysis, as one of the treatment methods of chronic renal failure, increases the oxidative stress, whose destructive activity is among other things manifested by changes in the lipid profile of the membranes of erythrocytes (RBC). Disturbances in the decomposition of membrane phospholipids are the causes of a lowered viability of red blood cells and an increased oligocytosis among hemodialysed patients. So far, reports do not, however, explain in a complex way the mechanism of how reactive oxygen species affect the functioning and the lipid profile of the cell membranes of erythrocytes. Besides, studies devoted to the mentioned problem provide contradictory results. It is being searched for new ways of decreasing the effects of the oxidative stress among patients with chronic illnesses in which free radicals are at the basis. One of the most frequently used methods of dialysis therapy is the usage of polysulfone membranes which to a great degree decrease the unwanted effects of hemodialysis. The information included in this work refer to data describing the effect of the oxidative stress in chronic renal failure, hemodialysis and preventive ways of decreasing the negative effects of an increased action of reactive oxygen species.

• [Atherogenic trans isomers of fatty acids in some food products]

  Authors: Ewa Stachowska, Katarzyna Luterek, Izabela Gutowska, Paulina Zyluk, Joanna Bober, Dariusz Chlubek

  Annales Academiae Medicae Stetinensis. 02/2006; 52(1):13-6; discussion 16-7.

  OBJECTIVE: Trans isomers of fatty acids (TFA) contain double bonds in their molecular structure with the trans configuration. Food products prominent for their TFA content include plant oilsOBJECTIVE: Trans isomers of fatty acids (TFA) contain double bonds in their molecular structure with the trans configuration. Food products prominent for their TFA content include plant oils (margarine), mayonnaise, products baked with plant oils, and ready-made glazes and icings. The so-called fast foods and snacks (bars, chips) represent a significant source of TFA, particularly for children and youth. Considering the potentially atherogenic properties of TFA, this work was undertaken to determine the content of the principal monounsaturated TFA in some food products ubiquitous on the market, i.e. margarines and snacks. MATERIAL AND METHODS: We studied bars (Snickers, Mars, Twix), chips (Lay's, Snack, Cheetos), and margarines (Rama Classic, Rama Olivio, Vita, Flora, Finea, Delma, Masmix, Krówka, Smakowita with butter, Extra Pomorskie). The content of TFA was determined with gas chromatography. RESULTS: The highest content ofmonounsatured TFA among sweets was disclosed for the Twix bar (2.94 microg/g), while the lowest for Snickers (0.3 microg/g). Among margarines, the highest content of TFA was found for Smakowita with butter (87.6 microg/g), Krówka (46 microg/g), and Vita (38.7 microg/g), whereas the content was lowest in Finea (0.12 microg/g) and Delma (0.14 microg/g). In the case of chips, the content was highest for Cheetos (3.5 microg/g) and lowest for Snack (0.09 microg/g). CONCLUSIONS: The content of atherogenic TFA in common food products varies widely. In some cases, the content of TFA is considerable and unjustly undisclosed by manufacturers. Promotion of these products should include information in respect of TFA. This conclusion is of particular importance considering the significance of these products in the diet of children and youth.

• GNB3 C825T and ACE I/D polymorphisms on the sodium-proton exchanger and the prevalence of essential hypertension in males.

  Authors: Karolina Kedzierska, Kazimierz Ciechanowski, Krzysztof Safranow, Joanna Bober, Edyta Gołembiewska, Ewa Kwiatkowska, Joanna Kabat-Koperska, Marek Ostrowski, Graźyna Adler, Dariusz Chlubek

  Archives of medical research. 01/2006; 37(1):150-7.

  BACKGROUND: The aim of the study was to verify the hypothesis if the interaction between the G protein beta3 subunit (GNB3) C825T polymorphism and ACE I/D polymorphism could lead to the disclosure ofBACKGROUND: The aim of the study was to verify the hypothesis if the interaction between the G protein beta3 subunit (GNB3) C825T polymorphism and ACE I/D polymorphism could lead to the disclosure of increased activity of sodium-proton exchanger and hypertension. METHODS: The study included 44 male patients, median age: 40 years. Patients were divided into two groups: 26 patients with essential hypertension (EH), and 18 subjects in the normotensive group (C). RESULTS: CT + TT genotypes of GNB3 predominated in patients with hypertension (65%) compared to normotensive patients (12%) (p <0.01). No significant differences were observed in the frequency of ACE gene polymorphisms between the examined groups. Significantly higher activity of erythrocyte NHE in patients with EH was observed: median 8.83 (interquartile range 4.27) mmol/l RBC/h, compared to C: median 6.18 (2.80) mmol/l RBC/h, p <0.001. Multiple logistic regression analysis showed that the presence of the T allele increased the risk of hypertension 16-fold (p <0.01) and higher erythrocyte NHE activity 2-fold per each unit of activity (p <0.01). DD genotype of ACE polymorphism did not increase the risk of hypertension. No significant interaction of the influence of GNB3 T allele and ACE DD genotype on the risk of hypertension was observed. In multiple linear regression analysis, none of the examined genotypes and their interactions influenced NHE activity. CONCLUSIONS: The presence of the T allele of GNB3 polymorphism and increased activity of erythrocyte NHE independently of ACE genotype increase the risk of hypertension.

• Copper modifies the activity of sodium-transporting systems in erythrocyte membrane in patients with essential hypertension.

  Authors: Karolina Kedzierska, Joanna Bober, Kazimierz Ciechanowski, Edyta Gołembiewska, Ewa Kwiatkowska, Iwona Noceń, Barbara Dołegowska, Grazyna Dutkiewicz, Dariusz Chlubek

  Biological trace element research. 10/2005; 107(1):21-32.

  The aim of the study was to verify the hypothesis if copper could influence the activity of sodium-transporting systems in erythrocyte membrane that could be related to essential hypertension. TheThe aim of the study was to verify the hypothesis if copper could influence the activity of sodium-transporting systems in erythrocyte membrane that could be related to essential hypertension. The examined group of patients consisted of 15 men with hypertension. The control group was 11 healthy male volunteers. The Na+/H+ exchanger (NHE) activity in erythrocytes was determined according to Orlov et al. The activity of transporting systems (ATP-Na+/K+; co-Na+/K+/Cl-; ex-Na+/Li+; free Na+ and K+ outflow [Na+, K+-outflow]) was determined according to Garay's method. The concentration of copper in plasma was assessed using atomic absorption spectrometry. The activity of ATP-Na+/K+ (micromol/L red blood cells [RBCs]/h) in hypertensive patients was 2231.5 +/- 657.6 vs 1750.5 +/- 291 in the control (p < 0.05), the activity of co-Na+/K+/Cl- (micromol/L RBCs/h) in hypertensives was 171.3 +/- 77.9 vs 150.7 +/- 53.9 in the control (NS). Na+-outflow (micromol/L RBCs/h) in hypertensives was 118.3 +/- 51.6 vs 113.3 +/- 24.4 in the control (NS). The K+-outflow (micromol/L RBCs/h) in hypertensives was 1361.7 +/- 545.4 vs 1035.6 +/- 188.3 in the control (NS). The activity of ex-Na+/Li+ (micromol/L RBCs/h) in hypertensive patients was 266.1 +/- 76.1 vs 204.1 +/- 71.6 in the control (p < 0.05). NHE activity (mmol/L RBCs/h) in hypertensives was 9.7 +/- 2.96 vs 7.7 +/- 1.33 in the control (p < 0.05). In hypertensive patients, negative correlation was found between the activity of Na+/K+/Cl- co-transport and plasma copper concentration (Rs = -0.579, p < 0.05) and between the activity of ex-Na+/Li+ and plasma copper concentration (Rs = -0.508, p < 0.05). Plasma copper concentration significantly influences the activity of sodium transporting systems in erythrocyte membrane. Copper supplementation could be expected to provide therapeutic benefits for hypertensive patients.

• Do trace elements modify the activity of erythrocyte sodium-proton exchanger in hemodialyzed patients?

  Authors: Joanna Bober, Ewa Kwiatkowska, Kazimierz Ciechanowski, Karolina Kedzierska, Barbara Dołegowska, Maria Olszewska, Elzbieta Kucharska, Edyta Gołembiewska, Dariusz Chlubek

  Biological trace element research. 06/2005; 104(2):107-20.

  The kinetics (Vmax and Km) of the erythrocyte Na+-H+ exchanger was studied in a group of 21 patients undergoing regular hemodialysis (HD) and in 21 control subjects. The activity of antioxidativeThe kinetics (Vmax and Km) of the erythrocyte Na+-H+ exchanger was studied in a group of 21 patients undergoing regular hemodialysis (HD) and in 21 control subjects. The activity of antioxidative enzymes--superoxide dismutase and glutathione peroxidase--as well as the concentrations of their cofactors--zinc, copper, and selenium--in plasma and in erythrocytes were determined. The thiobarbituric acid-reactive substances (TBARS) concentration served as an indicator of oxidative stress intensity in plasma and erythrocytes. It was found that in the control group the concentration of copper in erythrocytes was positively correlated with Km and Vmax. When the concentration of copper increased, the shape of the kinetic curve changed from sigmoidal to hyperbolic. In the control group, the concentration of zinc in erythrocytes also correlated with Km. However, the results obtained for the group of hemodialyzed patients were the opposite: when the erythrocyte concentration of copper increased, a Km decline was observed and the shape of the curve changed from hyperbolic to sigmoidal. In the group of hemodialyzed patients, we also found a positive correlation between Km and the concentration of selenium in erythrocytes, and a negative correlation between Km and erythrocyte TBARS.

• Trace elements modify the activity of sodium transporting systems in erythrocyte membrane in patients with essential hypertension-preliminary study.

  Authors: Karolina Kedzierska, Joanna Bober, Kazimierz Ciechanowski, Edyta Gołembiewska, Ewa Kwiatkowska, Iwona Noceń, Grazyna Dutkiewicz, Dariusz Chlubek

  Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. 03/2005; 20(2):469-71.

• Is conjugated linoleic acid (CLA) a protective factor in atherosclerosis? Study with the use of neural networks.

  Authors: Ewa Stachowska, Izabela Gutowska, Halina Szumiłowicz, Joanna Bober, Dariusz Chlubek

  Annales Academiae Medicae Stetinensis. 02/2005; 51(2):27-32.

  PURPOSE: Conjugated linoleic acid (CLA) is a term used for positional and geometrical isomers of linoleic acid whose two unsaturated bonds are separated by one saturated bond (cis9trans11 andPURPOSE: Conjugated linoleic acid (CLA) is a term used for positional and geometrical isomers of linoleic acid whose two unsaturated bonds are separated by one saturated bond (cis9trans11 and trans10cis12). Cooked meat and milk are among the richest dietary sources of CLA. Recently, much attention has been devoted to CLA due to its anti-cancer, anti-atherogenic, and anti-diabetic properties. MATERIAL AND METHODS: Our study group comprised 29 patients aged 45 to 75 years who were operated for atherosclerotic stenosis in the carotid arteries. RESULTS: Venous blood was collected after an overnight fast. Total cholesterol and triglycerides were assayed with enzymatic test kits. HDL-cholesterol was measured after precipitation with sodium magnesium phosphotungstate. LDL-cholesterol was calculated from total cholesterol, triglyceride and HDL-cholesterol concentrations using Friedewald's formula. A Perkin-Elmer gas chromatograph (model 8500) was used to analyze fatty acids methyl esters. Statistical analysis was performed with the Statistica Neural Networks software. Significantly lower plasma content of c9t11 CLA, linoleic, and arachidonic acids was found in the study group as compared with controls. Parametric analysis disclosed that c9t11 CLA concentrations depended on triglycerides and arachidonic acid in the study group and on linoleic acid and triglycerides in controls. An increase in total cholesterol concentration was associated with a decrease in the concentration of c9t11 CLA in the study group and a parallel increase in the control group.

• Does glucose present in the dialysate limit oxidative stress in patients undergoing regular hemodialysis?

  Authors: Joanna Bober, Ewa Kwiatkowska, Karolina Kedzierska, Maria Olszewska, Barbara Dolegowska, Leszek Domanski, Edyta Herdzik, Kazimierz Ciechanowski, Dariusz Chlubek

  Blood purification. 02/2005; 23(3):219-25.

  BACKGROUND: Decreased glucose concentration in the blood causes the inhibition of the hexose monophosphate (HMP) cycle in the erythrocyte. NADPH, which is the source of the reductive equivalentsBACKGROUND: Decreased glucose concentration in the blood causes the inhibition of the hexose monophosphate (HMP) cycle in the erythrocyte. NADPH, which is the source of the reductive equivalents necessary for the reproduction of glutathione (GSH), is not regenerated. The presence of glucose in dialysate should provide the stability of its concentration in the blood of patients undergoing hemodialysis (HD). The aim of the study was to assess the influence of glucose in the dialysate on the intensity of oxidative stress in patients undergoing regular HD. METHODS: The study comprised 43 patients hemodialyzed with dialysate containing (HD-g(+)) or not containing glucose (HD-g(-)). The concentrations of the products of reaction with thiobarbituric acid-reactive substance (TBARS) and GSH as well as the activity of erythrocyte superoxide dismutase were determined. Glucose concentrations in the blood before and immediately after dialysis were also measured. RESULTS: After flow-through dialysis the glucose concentration in the blood decreases both when dialysate does not contain glucose (4.8 vs. 1.6 mmol/l) and when dialysate contains glucose (6.6 vs. 5.8 mmol/l). HD caused changes in the TBARS concentration: in the HD-g(+) group the concentration decreased after HD, whereas in the HD-g(-) group it increased. In both groups of patients studied the GSH concentration changed after HD; in the HD-g(-) group it decreased and in the HD-g(+) group it increased. The results obtained in the groups of patients examined were confirmed by in vitro studies. CONCLUSIONS: The presence of glucose in the dialysate guarantees the normal activity of the HMP cycle, which provides the production of reductive equivalents for the regeneration of reduced GSH - free radicals scavenger - and therefore the limitation of oxidative stress.

• [Is hypertension after cyclosporin treatment related to sodium proton exchanger activity ?]

  Authors: Joanna Bober, Ewa Kwiatkowska, Karolina Kedzierska, Kazimierz Ciechanowski, Jacek Rózański, Dariusz Chlubek

  Polskie archiwum medycyny wewnȩtrznej. 04/2003; 109(3):223-8.

  A sodium-proton exchanger (NHE) is a membrane transport system taking part in intracellular sodium homeostasis. An increased NHE activity was observed in erythrocytes of primary hypertension (NTP)A sodium-proton exchanger (NHE) is a membrane transport system taking part in intracellular sodium homeostasis. An increased NHE activity was observed in erythrocytes of primary hypertension (NTP) patients. The clinical use of cyclosporine A has provided new perspectives in organ transplantation and in the treatment of autoimmune diseases but is accompanied by side effects like hypertension. Study group consisted of 40 patients with end stage renal failure (ESRF) before and after renal transplantation and 48 controls. The activity of NHE was significantly higher after transplantation than before renal transplantation (p = 0.05) and than control group (p = 0.05). There was positive correlation between NHE activity and cyclosporins blood level. We excluded (in vitro and in vivo study) the influence of uremic toxins on NHE activity in patients with ESRF before renal transplantation. It gave opportunity to compare the activity of NHE before and after renal transplantation according only to aspect of immunosuppressive treatment.