Publications by authors named "Sokolowska Magdalena"

16 Publications

  • Page 1 of 1

Clinical heterogeneity among pediatric patients with autoimmune type 1 diabetes stratified by immunoglobulin deficiency.

Pediatr Diabetes 2021 Apr 10. Epub 2021 Apr 10.

Department of Pediatrics, Oncology and Hematology, Medical University of Łódź, Sporna Str., Łódź, Poland.

Background: Type 1 diabetes (T1D) may coexist with primary immunodeficiencies, indicating a shared genetic background.

Objective: To evaluate the prevalence and clinical characteristics of immunoglobulin deficiency (IgD) among children with T1D.

Methods: Serum samples and medical history questionnaires were obtained during routine visits from T1D patients aged 4-18 years. IgG, IgA, IgM, and IgE were measured by nephelometry and ELISA. IgG and IgM deficiency (IgGD, IgMD) were defined as IgG/IgM > 2 standard deviations (SD) below age-adjusted mean. IgE deficiency was defined as IgE<2kIU/l. IgA deficiency (IgAD) was defined as IgA>2SD below age-adjusted mean irrespective of other immunoglobulin classes (absolute if <0.07 g/l, partial otherwise) and as selective IgAD when IgA>2SD below age-adjusted mean with normal IgG and IgM (absolute if <0.07 g/l, partial otherwise).

Results: Among 395 patients (53.4% boys) with the median age of 11.2 (8.4 - 13.7) and diabetes duration 3.6 (1.1 - 6.0) years, 90 (22.8%) were found to have hypogammaglobulinemia. The IgGD and IgAD were the most common each in 40/395 (10.1%). Complex IgD was found in 7 patients. Increased odds of infection-related hospitalization (compared to children without any IgD) was related to having any kind of IgD and IgAD; OR(95%CI)=2.1 (1.2-3.7) and 3.7 (1.8-7.5), respectively. Furthermore, IgAD was associated with having a first-degree relative with T1D OR(95%CI)=3.3 (1.4-7.6) and suffering from non-autoimmune comorbidities 3.3 (1.4 - 7.6), especially neurological disorders 3.5 (1.2 - 10.5).

Conclusions: IgDs frequently coexist with T1D and may be associated with several autoimmune and non-immune related disorders suggesting their common genetic background. This article is protected by copyright. All rights reserved.
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http://dx.doi.org/10.1111/pedi.13208DOI Listing
April 2021

Assessment of optimal insulin administration timing for standard carbohydrates-rich meals using continuous glucose monitoring in children with type 1 diabetes: A cross-over randomized study.

J Diabetes Investig 2019 Sep 18;10(5):1237-1245. Epub 2019 May 18.

Department of Children's Diabetology, Medical University of Silesia, Katowice, Poland.

Aims/introduction: The present study was an assessment of postprandial glucose concentration after carbohydrates-rich meals using continuous glucose monitoring in 30 children with type 1 diabetes treated using continuous subcutaneous insulin infusion with a rapid-acting insulin analog.

Materials And Methods: Over a period of 3 days, participants administered simple boluses with different delay times between insulin administration and the beginning of carbohydrates-rich meal consumption (meal no. 1 containing 197 kcal, no. 2 containing 247 kcal and meal no. 3 containing 323 kcal; containing practically no protein and fat). In the present cross-over randomized study, we analyzed the average glucose concentration profiles in 5-min intervals, mean glucose at insulin administration, mean glucose after 120 and 180 min, mean and peak glucose, glucose peak time, areas under the glucose and glucose increase curves, and time period lengths with glucose <50, 70 mg/dL, and >140 and 200 mg/dL.

Results: For test meals at 20-min versus 0-min delay time, the study exposed a longer median time period to reach peak glucose (95 vs 65 min, P = 0.01) after meals. A tendency to the lowest peak and mean glucose, and the longest time with glucose within a normal range was observed in patients who administered bolus insulin 20 min before a meal.

Conclusions: For carbohydrates-rich meals, administration of a proper dose of a rapid-acting insulin analog is crucial. The influence of rapid-acting insulin analog administration timing seems to be of minor importance in comparison with correct insulin dose adjustment; however, a tendency to achieve more balanced glucose profiles was found in a group who administered insulin 20 min before a meal.
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http://dx.doi.org/10.1111/jdi.13027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6717813PMC
September 2019

Remission phase in children diagnosed with type 1 diabetes in years 2012 to 2013 in Silesia, Poland: An observational study.

Pediatr Diabetes 2019 05 20;20(3):286-292. Epub 2019 Feb 20.

Department of Children's Diabetology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.

Background/objective: The study aimed to analyze the frequency of partial remission (PR) and its association with chosen clinical and laboratory factors among pediatric patients with newly diagnosed type 1 diabetes (T1D). The long-term effect of PR on chosen parameters was also investigated.

Methods: In 194 patients (95 girls) aged 8.1 ± 4.3 years, we analyzed data at T1D onset: glycemia, pH, C-peptide, antibodies, weight, and concomitant autoimmune diseases. Anthropometric parameters, daily insulin requirement (DIR), and HbA1c 2 and 4 years after T1D diagnosis were also analyzed. We determined PR based on HbA1c and DIR measurements at least every 3 months.

Results: PR occurred in 59% of patients. Remitters had significantly higher pH (7.33 vs 7.28, P = 0.03), weight SD score (SDS) (0.25 vs -0.24, P = 0.002), and body mass index SDS (0.19 vs -0.66, P = 0.02) compared with non-remitters. Concomitant diseases correlated negatively with PR. Multivariate analysis indicated only pH at onset was an independent predictor of PR. pH was the most important factor associated with the beginning of PR. There was a positive correlation between the start and duration of PR. Four years after T1D onset remitters had lower HbA1c (7.24% vs 8.05%, 53 vs 63.9 mmol/mol, P < 0.001) and DIR (0.81 vs 1.08, P = 0.005).

Conclusions: PR occurred quite often and developed more frequently in children with higher: weight and BMI SDS, but the main factor influencing PR presence and duration was higher pH at T1D onset. There was a beneficial impact of PR on HbA1c and DIR after 4 years of treatment.
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http://dx.doi.org/10.1111/pedi.12824DOI Listing
May 2019

Obesity and diabetes-Not only a simple link between two epidemics.

Diabetes Metab Res Rev 2018 10 17;34(7):e3042. Epub 2018 Jul 17.

Department of Children's Diabetology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.

Diabetes (DM) as well as obesity, due to their increasing incidence, were recognized as epidemic by the World Health Organization. Obesity is involved not only in the aetiopathogenesis of the most common worldwide type of DM-type 2 diabetes-but also in the development of its complications. There is also increasing scientific evidence regarding the role of obesity and overweight in type 1 diabetes. Weight gain may be considered as a complication of insulin treatment but also reveals significant pathophysiological impact on various stages of the disease. Another very important aspect related to DM as well as obesity is the microbiome, which is highly variable. The function of the gut microflora, its interaction with the whole organism, and its role in the development of obesity and type 1 diabetes as well as type 2 diabetes are still not fully understood and subject of ongoing investigations. This review presents a summary of recently published results concerning the relation of obesity/overweight and DM as well as their associations with the microbiome.
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http://dx.doi.org/10.1002/dmrr.3042DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6220876PMC
October 2018

Interleukin-6 Affects Aging-Related Changes of the PPARα-PGC-1α Axis in the Myocardium.

J Interferon Cytokine Res 2017 12 27;37(12):513-521. Epub 2017 Nov 27.

3 Department of Cardiology, Medical University of Bialystok , Bialystok, Poland .

Aging is related to gradual increase of interleukin 6 (IL-6) plasma level that affects peroxisome proliferator-activated receptor (PPAR) expression. We evaluated age-related changes in cardiac expression of PPARα, its coactivator PGC-1α, and selected downstream proteins in mice with systemic IL-6 knockout (IL6KO). Male C57BL6/J wild-type (WT) and IL6KO mice were used at the age of 16-20 weeks (young) and 24-30 months (senescent). Echocardiography and electron microscopy were applied to assess the function and ultrastructure of the heart. Western blotting and quantitative real-time PCR were used to estimate protein and mRNA levels of selected genes. PPARα expression in the myocardium of young IL6KO animals is lower and remains unchanged with aging, whereas in WT mice it declines with age and in both senescent groups it is equal. We observed aging-related upregulation of PGC-1α and less pronounced decline of Sirt3 in IL6KO animals; the level of cytochrome C was significantly decreased in IL6KO group only, suggesting disturbed mitochondrial function, which was not sufficient to evoke obvious changes in cardiac performance and function assessed by echocardiography. IL-6 and aging are involved in regulation of PPARα and PGC-1α expression and may influence the mitochondrial function.
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http://dx.doi.org/10.1089/jir.2017.0049DOI Listing
December 2017

Interleukin 6 modulates PPARα and PGC-1α and is involved in high-fat diet induced cardiac lipotoxicity in mouse.

Int J Cardiol 2016 Sep 13;219:1-8. Epub 2016 May 13.

Department of Cardiology, Medical University of Bialystok, Bialystok, Poland; Department of Population Medicine and Civilization Diseases Prevention, Medical University of Bialystok, Bialystok, Poland.

Background: Interleukin 6 (IL-6) may be involved in regulation of cardiac lipid metabolism and mitochondrial function through its influence on peroxisome proliferator-activated receptors (PPARs). In this study we evaluated the impact of the physiological level of IL-6 on the expression of PPARα and PGC-1α in the heart and the effect of lack of this cytokine on high-fat diet (HFD) induced lipotoxicity.

Methods: Male C57BL6/J wild type (WT) and IL-6 knock-out (IL-6KO) mice were used. 20 animals of each genotype were fed with HFD for 15-18weeks. Cardiac function was assessed using echocardiography and cardiomyocyte ultrastructure was examined using electron microscopy. QT-PCR and Western blotting were applied to estimate the expression of PPARα and PGC-1α at the transcriptional and protein levels.

Results: At baseline WT and IL-6KO mice had similar size and function of the left ventricle. HFD induced similar left ventricular hypertrophic response in both groups without causing heart failure, but only WT animals had increased resting ejection fraction of the LV. Ultrastructure of HFD groups showed markers of lipotoxicity, that were more pronounced in IL-6KO group. In basal conditions IL-6KO animals had lower PPARα and similar PGC-1α expression as compared to WT. HFD induced downregulation of both PPARα and PGC-1α in WT animals, while in IL-6KO mice this effect was constrained.

Conclusion: IL-6 is involved in basal regulation of PPARα and PGC-1α expression in cardiomyocytes. The lack of this cytokine promotes high-fat diet induced lipotoxicity but without overt manifestations of cardiac failure.
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http://dx.doi.org/10.1016/j.ijcard.2016.05.021DOI Listing
September 2016

The honeymoon phase - what we know today about the factors that can modulate the remission period in type 1 diabetes.

Pediatr Endocrinol Diabetes Metab 2016 ;22(2):66-70

Department of Children's Diabetology, School of Medicine in Katowice, Medical University Of Silesia, Katowice, Poland.

Certain patients with type 1 diabetes (T1DM), often shortly after initiating the treatment, may require smaller doses of insulin. This phenomenon is commonly referred to as the remission or honeymoon phase. In majority the remission is partial, but in very rare cases complete remission might occur. Recent studies have enlightened that an appropriate treatment and follow-up during the honeymoon could potentially enable the prolongation of this period for years or even permanently stop the destruction of the remaining ß cells, hence the renewal of interest on the subject. On average, the remission usually appears approximately 3 months after the insulin therapy was started. The duration of the partial remission ranges from 1 month up to 13 years, with an average of 9.2 months. Various clinical and metabolic factors have been analysed to assess whether they are influencing the remission rate and the duration of the honeymoon period. However, the degree of their influence is still a point of discussion. Also, new potential factors are investigated. This article gives an up-to-date status on recent papers concerning remission in T1DM.
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http://dx.doi.org/10.18544/PEDM-22.02.0053DOI Listing
November 2017

Remodeling of the intercalated disc related to aging in the mouse heart.

J Cardiol 2016 09 14;68(3):261-8. Epub 2015 Nov 14.

Department of Cardiology, Medical University of Bialystok, Bialystok, Poland.

Background: Aging is related to declined cardiac hemodynamic function. As pumping performance may be significantly related to slowed ventricular depolarization and non-synchronous contraction, we hypothesized that aging may cause dysfunction of intercalated disc (ID), which is the structure responsible for intercellular electrical communication between cardiomyocytes.

Methods: Male C57BL/6J mice were used for the study at two ages: 4 and 24 months. Electrocardiographic recording was made to analyze the time of ventricular depolarization. Then mice were killed, and the hearts were harvested for examination in transmission electron microscopy (TEM) and immunofluorescence imaging. The expression of connexin 43 (Cx43), N-cadherin, and β-catenin in the myocardium of the left ventricle was evaluated using Western blotting.

Results: In senescent mice, analysis of averaged QRS complex showed its significant prolongation. At the ultrastructural level, we found frequent disruptions of the ID (affecting 29±5% of them), mainly at the site of adherens junction, with relatively preserved desmosomal intercellular connections and diminished number of gap junctions. Western blotting revealed significantly decreased abundance of Cx43 protein in aged animals, which may cause slowed impulse propagation through the gap junctions and contribute to the observed electrocardiographic alterations. The level of RNA for Cx43 is similar between young and old animals, which suggests a post-transcriptional mechanism of Cx43 protein downregulation.

Conclusions: Our study shows age-related disorganization of ID, which may be responsible for slowed conduction of the depolarization wave within the heart, and supports the hypothesis of cardiac dysfunction in senescence.
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http://dx.doi.org/10.1016/j.jjcc.2015.10.001DOI Listing
September 2016

Enhanced expression of hepatocyte growth factor in the healing of experimental acute tympanic membrane perforation.

Int J Pediatr Otorhinolaryngol 2015 Jul 13;79(7):987-92. Epub 2015 Apr 13.

Department of General and Experimental Pathology, Medical University of Białystok, Mickiewicza 2c, 15-222 Białystok, Poland.

Objectives: The present study was performed to investigate the expression of hepatocyte (HGF), epidermal (EGF) and vascular endothelial (VEGF) growth factors in the course of healing of experimental tympanic membrane (TM) perforations in rats. The goal was to explain the role of these growth factors in the healing process of TM and to assess the possibility of their future application as healing promoters.

Methods: Seventy rats were used, of which 10 served as controls and the others had their TM perforated. The experimental animals were divided into six subgroups on the basis of time points (01, 03, 05, 07, 09, 15 day after injury). Videootoscopy and histology were employed to assess the morphology of the healing process. The expressions of HGF, EGF and VEGF were evaluated using Western blot analysis. Tissue localization of HGF was determined by the immunofluorescence method.

Results: HGF was hardly detectable in normal TM; however, a significant increase was noted in its expression starting from the third day after injury throughout the follow-up period, with the highest level on day 05. The analysis of HGF tissue localization with immunofluorescence revealed diffuse staining in the cytoplasm of proliferating epithelial cells. The expression of EGF was elevated on the first day after injury, not reaching statistical significance, and then returned to the level observed in the control TM. No significant differences were noted in the expression of VEGF.

Conclusion: High expression of HGF during the healing process of acute TM perforations makes it a promising candidate for further studies oriented towards its possible use in augmentation of TM healing.
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http://dx.doi.org/10.1016/j.ijporl.2015.04.004DOI Listing
July 2015

Binding of transition metal ions to albumin: sites, affinities and rates.

Biochim Biophys Acta 2013 Dec 26;1830(12):5444-55. Epub 2013 Jun 26.

Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, Warsaw 02-106, Poland. Electronic address:

Background: Serum albumin is the most abundant protein in the blood and cerebrospinal fluid and plays a fundamental role in the distribution of essential transition metal ions in the human body. Human serum albumin (HSA) is an important physiological transporter of the essential metal ions Cu(2+), and Zn(2+) in the bloodstream. Its binding of metals like Ni(2+), Co(2+), or Cd(2+) can occur in vivo, but is only of toxicological relevance. Moreover, HSA is one of the main targets and hence most studied binding protein for metallodrugs based on complexes with Au, Pt and V.

Scope Of Review: We discuss i) the four metal-binding sites so far described on HSA, their localization and metal preference, ii) the binding of the metal ions mentioned above, i.e. their stability constants and association/dissociation rates, their coordination chemistry and their selectivity versus the four binding sites iii) the methodology applied to study issues of items i and ii and iv) oligopeptide models of the N-terminal binding site.

Major Conclusions: Albumin has four partially selective metal binding sites with well-defined metal preferences. It is an important regulator of the blood transport of physiological Cu(II) and Zn(II) and toxic Ni(II) and Cd(II). It is also an important target for metal-based drugs containing Pt(II), V(IV)O, and Au(I).

General Significance: The thorough understanding of metal binding properties of serum albumin, including the competition of various metal ions for specific binding sites is important for biomedical issues, such as new disease markers and design of metal-based drugs. This article is part of a Special Issue entitled Serum Albumin.
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http://dx.doi.org/10.1016/j.bbagen.2013.06.018DOI Listing
December 2013

Effect of common buffers and heterocyclic ligands on the binding of Cu(II) at the multimetal binding site in human serum albumin.

Bioinorg Chem Appl 2010 5:725153. Epub 2010 May 5.

Department of Hygiene, Wrocław Medical University, Mikulicza-Radeckiego 7, 50-345 Wrocław, Poland.

Visible-range circular dichroism titrations were used to study Cu(II) binding properties of Multimetal Binding Site (MBS) of Human Serum Albumin (HSA). The formation of ternary MBS-Cu(II)-Buffer complexes at pH 7.4 was positively verified for sodium phosphate, Tris, and Hepes, the three most common biochemical buffers. The phosphate > Hepes > Tris order of affinities, together with strong spectral changes induced specifically by Tris, indicates the presence of both Buffer-Cu(II) and Buffer-HSA interactions. All complexes are strong enough to yield a nearly 100% ternary complex formation in 0.5 mM HSA dissolved in 100 mM solutions of respective buffers. The effects of warfarin and ibuprofen, specific ligands of hydrophobic pockets I and II in HSA on the Cu(II) binding to MBS were also investigated. The effects of ibuprofen were negligible, but warfarin diminished the MBS affinity for Cu(II) by a factor of 20, as a result of indirect conformational effects. These results indicate that metal binding properties of MBS can be modulated directly and indirectly by small molecules.
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http://dx.doi.org/10.1155/2010/725153DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2864911PMC
June 2010

Spectroscopic and thermodynamic determination of three distinct binding sites for Co(II) ions in human serum albumin.

J Inorg Biochem 2009 Jul 3;103(7):1005-13. Epub 2009 May 3.

Department of Hygiene, Wroclaw Medical University, Wroclaw, Poland.

Human serum albumin (HSA) is the most abundant protein of blood serum, involved in the transport of metal ions, including Co(II). Using circular dichroism spectroscopic titrations we characterized three distinct Co(II) binding sites in HSA. Applying Cu(II), Ni(II) and Cd(II) ions as competitors we determined that these sites are identical with three binding sites known for other metal ions. We ordered these sites according to their binding affinities as cadmium site B (CdB)>multi-metal binding site (MBS)>N-terminal binding site (NTS). Using isothermal titration calorimetry (ITC) we confirmed the presence of these three binding sites and determined their conditional binding constants at pH 7.4 as 9+/-5, 1.1+/-0.5, and 0.9+/-0.3x10(4)M(-1), respectively. The impact of these results on the albumin cobalt binding (ACB) clinical assay for myocardial ischemia is discussed.
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http://dx.doi.org/10.1016/j.jinorgbio.2009.04.011DOI Listing
July 2009

Human serum albumin coordinates Cu(II) at its N-terminal binding site with 1 pM affinity.

J Biol Inorg Chem 2007 Aug 22;12(6):913-8. Epub 2007 May 22.

Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland.

The conditional stability constant at pH 7.4 for Cu(II) binding at the N-terminal site (NTS) of human serum albumin (HSA) was determined directly by competitive UV-vis spectroscopy titrations using nitrilotriacetic acid (NTA) as the competitor in 100 mM NaCl and 100 mM N-(2-hydroxyethyl)piperazine-N'-ethanesulfonic acid (Hepes). The log Kc (NTS) value of 12.0 +/- 0.1 was determined for HSA dissolved in 100 mM NaCl. A false log log Kc (NTS) (c) value of 11.4 +/- 0.1 was obtained in the 100 mM Hepes buffer, owing to the formation of a ternary Cu(NTA)(Hepes) complex. The impact of the picomolar affinity of HSA for Cu(II) on the availability of these ions in neurodegenerative disorders is briefly discussed.
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http://dx.doi.org/10.1007/s00775-007-0244-8DOI Listing
August 2007

Cu(II) complexation by "non-coordinating" N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES buffer).

J Inorg Biochem 2005 Aug;99(8):1653-60

Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland.

The combined potentiometric and spectroscopic studies of interactions of N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) with Cu(II) demonstrated that this popular buffer, commonly labelled as "non-coordinating" forms a CuL+ complex, with the logbeta(CuL) value of 3.22. This complex undergoes alkaline hydrolysis above pH 6, resulting in Cu(OH)2 precipitation. However, the presence of HEPES at a typical concentration of 100 mM at pH 7.4 elevates the apparent binding constant, being determined for a complex of another ligand, by a factor of 80. HEPES does not form ternary complexes with aminoacids Ala, Trp, and His, but may do so with other bioligands, such as nucleotides. Therefore, HEPES can still be recommended for Cu(II) studies in place of other common buffers, such as Tris and phosphate, but appropriate corrections and precautions should be applied in quantitative experiments.
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http://dx.doi.org/10.1016/j.jinorgbio.2005.05.007DOI Listing
August 2005

Correlations between complexation modes and redox activities of Ni(II)-GSH complexes.

Chem Res Toxicol 2003 Jul;16(7):855-64

Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland.

The formation of Ni(II) complexes of GSH in conditions of 4-fold GSH excess over Ni(II) was studied by potentiometric titrations, UV-vis and CD spectroscopies, and magnetic susceptibility measurements. The following set of complexes was obtained in the pH range of 6-12: NiHL, Ni(2)L(2)(2)(-), NiHL(2)(3)(-), NiL(2)(4)(-), and NiH(-)(1)L(2)(5)(-). The first of these is an octahedral species, coordinated through the donors of the Glu moiety of GSH, while the remaining ones are largely square-planar, with participation of the thiol in Ni(II) coordination. Magnetic moments indicate the presence of a spin equilibrium for Ni(2)L(2)(2)(-), NiHL(2)(3)(-), and NiL(2)(4)(-) complexes. Phosphate ions apparently decompose the Ni(2)L(2)(2)(-) complex, converting it into a monomeric, high spin, ternary species. Among the molecular forms of GSH, HL(2)(-) is the one most susceptible to air oxidation, due to a presence of ionic interactions between its protonated amine and deprotonated thiol moieties. The complexation of Ni(II) accelerates air oxidation of GSH in alkaline solutions by a factor of 4, but this effect is absent at neutral pH. The damage to plasmid DNA by H(2)O(2) is facilitated by Ni(II) ions and inhibited by excess of GSH. However, the analysis of the concentration profile of this process indicates that octahedral Ni(II) complexes with GSH are involved in the formation of double strand breaks. Finally, numerical simulations of intracellular Ni(II) distribution, made possible by the determination of stability constants of Ni(II) complexes of GSH, indicate that histidine and ATP, rather than GSH, may act as ligands for Ni(II) in vivo. Altogether, our results suggest that the direct impact of GSH on Ni(II) toxicity may be of a limited character.
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http://dx.doi.org/10.1021/tx034012kDOI Listing
July 2003

Short peptides are not reliable models of thermodynamic and kinetic properties of the N-terminal metal binding site in serum albumin.

Eur J Biochem 2002 Feb;269(4):1323-31

Faculty of Chemistry, University of Wroclaw, Poland.

A comparative study of thermodynamic and kinetic aspects of Cu(II) and Ni(II) binding at the N-terminal binding site of human and bovine serum albumins (HSA and BSA, respectively) and short peptide analogues was performed using potentiometry and spectroscopic techniques. It was found that while qualitative aspects of interaction (spectra and structures of complexes, order of reactions) could be reproduced, the quantitative parameters (stability and rate constants) could not. The N-terminal site in HSA is much more similar to BSA than to short peptides reproducing the HSA sequence. A very strong influence of phosphate ions on the kinetics of Ni(II) interaction was found. This study demonstrates the limitations of short peptide modelling of Cu(II) and Ni(II) transport by albumins.
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http://dx.doi.org/10.1046/j.1432-1033.2002.02772.xDOI Listing
February 2002