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Janusz Szemraj

Publications and source records attributed to Janusz Szemraj.

At least 19 recordsLinked to original sources
PubMed2006

The expression of cytochrome P-450 and cytochrome P-450 reductase genes in the simultaneous transformation of corticosteroids and phenanthrene by Cunninghamella elegans.

The expression of cytochrome P-450 and cytochrome P-450 reductase (CPR) genes in the conterminous biotransformation of corticosteroids and PAHs was studied in Cunninghamella elegans 1785/21Gp. We had previously used this strain as a microbial eucaryotic model for studying the relationship between mammalian steroid hydroxylation and the metabolization of PAHs. We reported that cytochrome P-450 reductase is involved in the biotransformaton of cortexolone and phenanthrene. RT-PCR and Northern blotting analyses indicated that the cytochrome P-450 and CPR genes appear to be inducible by both steroids and PAHs. The expression of the cytochrome P-450 gene was increased ninefold and the expression of the CPR gene increased 6.4-fold in cultures with cortexolone and/or phenanthrene in comparison with controls. We conclude that the increase in cytochrome P-450 gene expression was accompanied by an increase in cytochrome P-450 enzymatic activity levels.

Biotransformation↗
PubMed2006

[Functional polymorphism of manganese superoxide dismutase (MnSOD) gene correlates with schizophrenia in Polish population].

UNLABELLED: Neuro-developmental theory paid attention to an apoptosis role and reactive oxygen species (ROS) in schizophrenia pathogenesis. ROS concentration in cells is maintained on a low level due to manganese superoxide dismutase activity (MnSOD). THE AIM OF THE WORK: An attempt of evaluation of Ala-9Val polymorphism in gene for MnSOD in schizophrenic patients and control group was undertaken. MATERIAL AND METHODS: 122 paranoid schizophrenia patients were asked to the study. Clinical evaluation were performed by using PANSS. RESULTS: Alleles layout in control group (Val 45.95%) and an under-study group (Val 73.77%) was statistically different. Genotype layout also differentiated the groups. The under-study group: Ala/Ala--10.65%, Val/Ala--31.15%, Val/Val--58.2%; and in the control group respectivelly: 37.84%, 32.43%, 29.73%. relative risk for developing schizophrenia in people having in their polymorphism for MnSOD genotype Val-9Val is over three times (RR = 3.29) higher than for people not having this genotype. While evaluating correlations between a genotype, frequency of Ala-9Val allele polymorphism and social - demographic and clinical data of schizophrenic patients, no statistically substantial correlations were observed, even though there was a close to gravity correlation between a genotype Val-9Val and negative disease symptoms (p = 0.075). CONCLUSIONS: 1. In Polish populations there is a statistically substantial associations between schizophrenia incidence a genotype Val-9Val in gene for MnSOD. 2. The lack of association between selected social - demographic and clinical factors of schizophrenic patients and Ala-9Val polymorphism in a gene for MnSOD. 3. Risk for developing schizophrenia in people having Val-9Val genotype in a gene for MnSOD is over three times higher than for people not having this very genotype.

Female↗
PubMed2006

[Staphylokinase--a specific plasminogen activator].

Staphylokinase is a 135 amino acid protein produced by certain strains of Staphylococcus aureus. It belongs to fibrin-specific plasminogen activator. Staphylokinase converts plasminogen--the inactive proenzyme--to the plasmin, which dissolves the fibrin of a blood clots. This review will focus on the biochemical and thrombolytic properties of staphylokinase and its derivatives, which would make use of treatment in acute myocardial infarction and other cardiovascular diseases.

Animals↗
PubMed2005

Tissue distribution of a menthyl-conjugated oligodeoxyribonucleotide antisense to PAI-1 mRNA.

The inhibitory effect of numerous analogues of PO-16, an hexadecadeoxyribonucleotide antisense to sequences -22 to -17 of PAI-1 mRNA coding for a fragment of the signal peptide, on the expression of PAI-1 in endothelial cells, and physiological consequences of the subsequently reduced PAI-1 activity tested in vitro and in vivo, were described in our previous studies. Of particular interest was PO-16 5'-O-conjugated with menthyl phosphorothioate (MPO-16R). In this work, tissue localisation of MPO-16R labelled with [(35)S] phosphorothioate at the 3'-end, was determined. [(35)S]MPO-16R and control [(35)S]MPO-16R-SENSE oligonucleotides were administered intravenously into 22 rats and organ distribution of the labelled bioconjugates was assessed after 24 and 48 h. For this purpose, tissue sections were subjected to autoradiography, and quantitated by liquid scintillation after solubilisation. Overall clearance of radioactivity was already seen after 24 h, with the radioactivity recovered mainly in the kidney and liver. A smaller fraction of radioactivity was also retained in the spleen and heart. The kidney concentration of the labelled probe was higher than that of liver by 50%. The distribution of PAI-1 mRNA in untreated rat kidney, liver, spleen and heart established by two independent techniques: Ribonuclease Protection Assay and Real-Time PCR, shows the same pattern as that observed for [(35)S]MPO-16R antisense.

Animals↗
PubMed2005

Anti-oxidant activity of spermine and spermidine re-evaluated with oxidizing systems involving iron and copper ions.

This study was designed to investigate the direction of redox reactions of spermine and spermidine in the presence of iron and copper. The redox activity of spermine and spermidine was assessed using a variety of methods, including their ability to: (1) reduce Fe(3+) to Fe(2+) ions; (2) protect deoxyribose from oxidation by Fe(2+)-ethylene diaminetetraacetic acid, Fe(3+)-ethylene diaminetetraacetic acid systems with and without H(2)O(2); (3) protect DNA from damage caused by Cu(2+)-H(2)O(2), and Fe(2+)-H(2)O(2) with and without ascorbic acid; (4) inhibit H(2)O(2)-peroxidase-induced luminol dependent chemiluminescence; (5) scavenge diphenyl-picryl-hydrazyl radical. Spermine and spermidine at concentration 1mM reduced 1.8+/-0.3 and 2.5+/-0.1 nmol of Fe(3+) ions during 20 min incubation. Both polyamines enhanced deoxyribose oxidation. The highest enhancement of 7.6-fold in deoxyribose degradation was found for combination of spermine with Fe(3+)-ethylene diaminetetraacetic acid. An 10mM spermine and spermidine decreased CuSO(4)-H(2)O(2)-ascorbic acid- and FeSO(4)-H(2)O(2)-ascorbic-induced DNA damage by 73+/-6, 69+/-4% and 90+/-5, 53+/-4%, respectively. They did not protect DNA from CuSO(4)-H(2)O(2) and FeSO(4)-H(2)O(2). Spermine apparently increased the CuSO(4)-H(2)O(2)-dependent injury to DNA. Polyamines attenuated H(2)O(2)-peroxidase-induced luminol dependent chemiluminescence. Total light emission from specimens containing 10mM spermine or spermidine was attenuated by 85.3+/-1.5 and 87+/-3.6%. During 20 min incubation 1mM spermine or spermidine decomposed 8.1+/-1.4 and 9.2+/-1.8% of diphenyl-picryl-hydrazyl radical. These results demonstrate that polyamines of well known anti-oxidant properties may act as pro-oxidants and enhance oxidative damage to DNA components in the presence of free iron ions and H(2)O(2).

Animals↗
PubMed2005

Mast cell-derived exosomes activate endothelial cells to secrete plasminogen activator inhibitor type 1.

OBJECTIVE: Previous studies supported the contribution of exosomes to an acellular mode of communication, leading to intercellular transfer of molecules. In this study we provide evidence that mast cell-derived exosomes induce plasminogen activator inhibitor type 1 (PAI-1) expression in endothelial cells, detectable at the level of PAI-1 mRNA and protein synthesis. The stimulating effect was also measured at the level of PAI-1 promoter activity. METHODS AND RESULTS: To identify components responsible for this activity, exosome proteins were separated by 2-dimensional PAGE, and protein spots were identified by microsequencing using electrospray (ISI-Q-TOF-Micromass) spectrometer. Components of 3 independent systems that can be involved in activation of endothelial cells, namely the prothrombinase complex, tumor necrosis factor-alpha, and angiotensinogen precursors were identified. Procoagulant activity of exosomes was confirmed by a thrombin generation assay using a specific chromogenic substrate. Because the potential of mast cell-derived exosomes to induce PAI-1 expression was completely abolished by hirudin, thrombin generated on exosomes seems to be responsible for this activity. CONCLUSIONS: It can be concluded that mast cell-derived exosomes via significant upregulation of PAI-1 secretion from endothelial cells may provide feedback between the characteristically increased PAI-1 levels and procoagulant states, both observed in diverse syndromes manifesting as endothelial cell dysfunction.

Cell Communication↗
PubMed2005

Magnesium sulfate effect on erythrocyte membranes of asphyxiated newborns.

OBJECTIVES: Magnesium sulfate has been recognized as a neuroprotective agent against hypoxia-ischemia, mainly by the protection from the excitotoxicity associated with increased glutamate concentration. However, the mechanism of MgSO4 action is not fully understood and is considerably controversial. DESIGN AND METHODS: During the 2 first hours of life, the asphyxiated full-term newborns were treated intravenously with one dose of MgSO4 250 mg/kg body weight. At birth, after 6 and 48 h of life the activity of ATP-dependent enzymes in erythrocyte membranes: Mg2+-ATPase, Ca2+-ATPase, protein kinases A and C, were determined. Using monoclonal antibodies, the band 3 and its phosphotyrosine level were also assayed. RESULTS: The time-dependent decrease of Ca2+-ATPase activity was detected in untreated newborns, whereas MgSO4 prevented this reduction. After 48 h, protein kinases activities differed in MgSO4-treated and untreated groups. Magnesium therapy increased the amount of band 3 and diminished proteolytic degradation of this protein. CONCLUSION: Our results demonstrated, for the first time, that magnesium sulfate treatment significantly altered the activities of some important enzymes in erythrocyte membrane from asphyxiated newborns. It also reduced the post-asphyxial damages of membrane compounds. These data may partly explain the molecular mechanisms of MgSO4 action in asphyxiated newborns.

Anion Exchange Protein 1, Erythrocyte↗
PubMed2005

Induction of PAI-1 expression by tumor necrosis factor alpha in endothelial cells is mediated by its responsive element located in the 4G/5G site.

Plasminogen activator inhibitor type 1 (PAI-1) is induced by many proinflammatory and pro-oxidant factors. Among them, tumor necrosis factor alpha (TNFalpha), a pivotal early mediator that regulates and amplifies the development of inflammation, is one of the strongest PAI-1 synthesis activators. Location of the TNFalpha response element in the PAI-1 promoter is still ambiguous. In this study, we attempted to evaluate the significance of the element located in the 4G/5G site of the PAI-1 promoter in the TNFalpha stimulation of PAI-1 expression in endothelial cells. PAI-1 expression was monitored at: (a) the level of mRNA using real-time PCR, (b) PAI-1 gene transcription by transfection reporter assays, and (c) protein synthesis using the enzyme immunoassay. NF-kappaB activity was monitored using the electrophoretic mobility shift assay. Its activity was modified by either antisense oligonucleotides or transfection of endothelial cells with the wild-type or mutated IkappaBalpha. We have shown that TNFalpha-induced expression and gene transcription of PAI-1 involves a regulatory region present in segment -664/-680 of the PAI-1 promoter. This reaction involves the TNFalpha-induced generation of superoxide leading to activation of NF-kappaB, and can be abolished by antioxidants and by overexpression of a super-suppressor phosphorylation-resistant IkappaBalpha. Stimulation of PAI-1 under these conditions involves the motif of the PAI-1 promoter adjacent to the 4G/5G site, which can directly interact with NF-kappaB. We show that activation of PAI-1 gene by TNFalpha and reactive oxygen species is mediated by interaction of NF-kappaB with the cis-acting element located in the -675 4G/5G insertion/deletion in the PAI-1 promoter.

Acetylcysteine↗
PubMed2005

Antioxidant properties of carnosine re-evaluated with oxidizing systems involving iron and copper ions.

Carnosine has antioxidant properties and is efficient in the treatment of chemically-induced inflammatory lesions in animals. However, some studies question its biological significance as antioxidant and show lack of protection and even pro-oxidant effect of carnosine in systems containing nickel and iron ions. The ability of carnosine to: (1) reduce Fe(3+) into Fe(2+) ions; (2) protect deoxyribose from oxidation by Fe(2+)-, Fe(3+)-, and Cu(2+)-H(2)O(2)-EDTA systems; (3) protect DNA from damage caused by Cu(2+)-, and Fe(2+)-H(2)O(2)-ascorbate systems; (4) inhibit HClO- and H(2)O(2)-peroxidase-induced luminol dependent chemiluminescence was tested in vitro. At concentration 10 mM carnosine reduced 16.6+/-0.5 nmoles of Fe(3+) into Fe(2+) ions during 20 min. incubation and added to plasma significantly increased its ferric reducing ability. Inhibition of deoxyribose oxidation by 10 mM carnosine reached 56+/-5, 40+/-11 and 30+/-11% for systems containing Fe(2+), Fe(3+) and Cu(2+) ions, respectively. The damage to DNA was decreased by 84+/-9 and 61+/-14% when Cu(2+)-, and Fe(2+)-H(2)O(2)-ascorbate systems were applied. Combination of 10 mM histidine with alanine or histidine alone (but not alanine) enhanced 1.3 and 2.3 times (P<0.05) the DNA damage induced by Fe(2+)-H(2)O(2)-ascorbate. These amino acids added to 10 mM carnosine decreased 3.1-fold (P<0.05) its protective effect on DNA. Carnosine at 10 and 20 mM decreased by more than 90% light emission from both chemiluminescent systems. It is concluded that carnosine has significant antioxidant activity especially in the presence of transition metal ions. However, hydrolysis of carnosine with subsequent histidine release may be responsible for some pro-oxidant effects.

Animals↗
PubMed2005

Angiotensin II enhances thrombosis development in renovascular hypertensive rats.

There is an increased number of in vitro evidence that angiotensin II (Ang II) may promote thrombosis. However there are no in vivo experiments exploring the effect of Ang II on thrombus formation. In the present study we have investigated the influence of Ang II on venous thrombosis in renovascular hypertensive rats. Furthermore, we examined the role of AT(1) receptor and Ang II metabolites: angiotensin III (Ang III) and angiotensin IV (Ang IV) in the mechanisms of Ang II action. The contribution of coagulation and fibrinolytic systems in the mode of Ang II action was also determined. Venous thrombosis was induced by ligation of vena cava. Ang II infused into rats developing venous thrombosis caused dose-dependent increase in thrombus weight, which was partially reversed by losartan, selective AT(1) antagonist. Ang III did not influence the thrombus formation in hypertensive rats, while Ang IV caused a marked increase in thrombus weight only in one of the used doses. Our study shows that Ang II via AT(1) receptor enhances thrombosis development. The prothrombotic effect of Ang II may partially depend on enhanced leukocytes adhesion to endothelial cells accompanied by accelerated fibrin formation and increased plasma level of PAI-1. Moreover, Ang II action is partially mediated by one of its metabolites - Ang IV.

Angiotensin II↗
PubMed2005

[Significance of MDM2 protein in the cell cycle].

The basis of oncogenesis underlies the modification of the control of the cell cycle, which leads to disturb balance between proliferation and apoptosis. The MDM2 protein suppresses the ability of p53 to activate genes responsible for repairing or apoptosis, but also promotes p53 degradation by ubiquitination. MDM2 inhibits tumor suppressor property of pRb, by releasing E2F1, which stimulates DNA synthesis in S-phase. MDM2 influences on the neuronal and muscle differentiation. Quantity and stability of the MDM2 protein is regulated by p73, p53, TSG101, p14ARF and Ras-Raf-MEK-ERK pathway. Changes of the level of the MDM2 can disturb control of cell cycle and contribute to oncogenesis.

Apoptosis↗
PubMed2005

[The influence of nitric oxide on the regulation of plasminogen activator inhibitor type 1 and tissue-type plasminogen activator expression].

Nitric oxide produced in various human tissues by nitric oxide synthase is involved in the regulation of many physiological processes. Mechanism of its action is diverse. The most important physiological activity of nitric oxide is guanylate cyclase activation and an increase of cGMP synthesis. At low concentrations NO plays a pivotal role in vessel relaxation and possesses antithrombotic, antiproliferative and anti-inflammatory features as well. An excessive production of nitric oxide can disturb vascular hemostasis and contribute to development of cardiovascular diseases. Studies provide that NO also participate in fibrynolysis regulation by the influence on the PAI-1 and t-PA expression, what may have important clinical implications. The aim of this review is to present current knowledge about the role of nitric oxide in the regulation of these plasminogen activation system factors.

Animals↗
PubMed2004

The effect of antisense oligonucleotide treatment of plasma membrane Ca(+2)-ATPase in PC12 cells.

Plasma membrane Ca(+2)-ATPase (PMCA), encoded by four separate genes, constitutes a high affinity system extruding Ca(+2) outside the cell. The nerve growth factor-treated PC12 cell line possesses all four main PMCA isoforms. To evaluate the potential role of PMCA isoforms in the differentiation process, we transiently suppressed the expression of PMCA2 and 3 using the antisense oligonucleotides. In the transfected PC12 cells, we observed morphological changes, slowed neurite extension and diminished survival of the cells. The apparent transport activity and affinity of the calcium pump to Ca(+2) were lower in the cells with suppressed PMCA2 and 3 isoforms than in the control cells. Moreover, in the transfected PC12 plasma membranes, the calcium pump was insensitive to stimulation by calmodulin. These findings suggest that PMCA2 and 3 isoforms may be involved in developmental and differentiation processes.

Animals↗
PubMed2003

Thymosin beta 4 induces the synthesis of plasminogen activator inhibitor 1 in cultured endothelial cells and increases its extracellular expression.

Thymosin beta 4(T beta 4), a 4.9-kDa polypeptide primarily known as a main G-actin-sequestering peptide, is present in high concentrations in various cells and in the circulation. We have found that T beta 4 upregulates the expression of plasminogen activator inhibitor 1 (PAI-1) in endothelial cells measured both at the level of mRNA and protein synthesis. This effect seems to be cell specific and was not observed when other cells such as human fibroblasts, PC3, and U937 were tested. T beta 4 significantly activated the PAI-1 promoter in EA.hy 926 cells transiently transfected either with plasmid p800LUC containing PAI-1 promoter fragment (-800 to +71) or the PAI-1 promoter linked with green fluorescent protein. T beta 4 mediated up-regulation of PAI-1 involved activation of the mitogen-activated protein kinase cascade. Furthermore, T beta 4 enhanced c-Fos/c-Jun DNA-binding activity to the activator protein 1 (AP-1)-like element (-59 to -52). The specificity of this binding activity was demonstrated by competition electrophoretic mobility shift assay and after transfection of EA.hy 926 cells with the mutated PAI-1 promoter. Taken together, these data indicate that, in response to T beta 4 stimulation, AP-1 activity increases to enhance PAI-1 transcription through its unique AP-1-like element at -59 to -52 in the PAI-1 promoter.

Cells, Cultured↗
PubMed2003

A competitor DNA template for the molecular quantification of the hepatitis B virus.

The molecular determination of viral load in the serum represents the most valuable prognostic marker of HBV infection. In this paper, a new molecular assay for the quantitative measurement of HBV presence is described. It is based on PCR performing with a HBV-specific competitor DNA template. For the construction of the DNA template, a HBV DNA-originated 436 bp DNA fragment was modified by introducing a 110 bp deletion and cloned into pUC19. The resulting vector serves as the competitor DNA template in the competitive PCR. Post-PCR, the competitor DNA generates an amplified fragment of 306 bp; it could be easily distinguished from the product generated from the viral-originated DNA product (416 bp) when the same primers are used. The quantitative ratio between the two products enables the quantitative determination of viral load. The range of the HB-PCR assay is from 3 x 10(4)to 6 x 10(10) particles/ml. A serum HBV load determination performed by HB-PCR assay indicated a close correlation with the results of the Quantiplex HBV DNA assay (bDNA). The HB-PCR assay is cheap, reliable and easy to use in any laboratory working with PCR methods.

DNA, Viral↗
PubMed2002

Cerivastatin, a HMG-CoA reductase inhibitor, reduces plasminogen activator inhibitor-1 (PAI-1) expression in endothelial cells by down-regulation of cellular signaling and the inhibition of PAI-1 promoter activity.

Statins, which competitively inhibit 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity and reduce mevalonate synthesis, are believed to exert a plethora of pleiotropic effects. In this report, molecular mechanisms of the inhibitory effect on plasminogen activator inhibitor type 1 (PAI-1) expression produced by cerivastatin (CRV), the most active compound in this class, were studied using monocultures of human endothelial cell line (EA.hy 926). CRV similar to another statin, lovastatin (LOV), significantly inhibited PAI-1 expression and its release from endothelial cells, nonstimulated and stimulated with TNF-alpha. The inhibitory effect of CRV could be detected at the level of PAI-1 promoter in EA.hy 926 cells transfected with plasmid p800 LUC containing PAI-1 promoter fragment (+71 to -800), as well as at the level of PAI-1 mRNA. The PAI-1 promoter activity was markedly suppressed in the nonstimulated cells and almost completely inhibited in TNF-alpha-stimulated cells. In addition, CRV at low doses (IC(50) of 4 - 6 microM) significantly inhibited mitogen-activated protein kinases (MAPKs) phosphorylation. The majority of inhibitory effects occurred at significantly lower concentrations for CRV compared to LOV. The mechanism by which CRV inhibits PAI-1 expression appears to be directly associated with geranylgeranylation of some cell proteins, since the inhibitory effect on PAI-1 expression can be reversed by geranylgeranyl-pyrophosphate but not by farnesyl-pyrophosphate.

Cells, Cultured↗
PubMed2002

The isoform- and location-dependence of the functioning of the plasma membrane calcium pump.

The plasma membrane is a specialised multi-component structure with inter- and intracellular signalling functions. Ca2+ plays a crucial role in cellular physiology, and an ATP-driven plasma membrane calcium pump (PMCA) plays the greatest role in the maintenance of a low free Ca2+ concentration in the cytoplasm. The enzyme is coded by four separate genes (PMCA 1-4), and, due to alternative splicing, more than 20 variants can exist. PMCA 1 and 4 isoforms are present in almost all tissues, whereas PMCA 2 and 3 are found in more specialised cell types. The variants differ primarily in their regulatory regions, thus the modulation of calcium pump activity strongly depends on the isoform and the membrane composition. The unique function of PMCA isoforms was confirmed using the practical experimental models - a rat pheochromocytoma cell line, a human neuroblastoma cell line, or, more recently, knockout mice. In addition, based on the finding that PMCA could interact with several specific signaling proteins, it was concluded that its location in defined sites of the cell membrane could be a prerequisite for efficient intercellular communication.

Animals↗