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  • 1.
    Abuabaid, Hanan
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Karlsson, Mattias
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Olsson, Per-Erik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Jass, Jana
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Probiotic Lactobacillus rhamnosus alters inflammatory responses of bladder epithelial and macrophage-like cells in co-cultureManuskript (preprint) (Övrigt vetenskapligt)
  • 2.
    Berg, Håkan
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Liimatta, Harri
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hoffmann, Erik
    Karlsson, Johnny
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Characterization of antibodies for quantitative determination of spiggin protein levels in male and female three-spined stickleback (Gasterosteus aculeatus)2009Ingår i: Reproductive Biology and Endocrinology, ISSN 1477-7827, E-ISSN 1477-7827, Vol. 7, nr 1, artikel-id 46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Spiggin is an adhesive glycoprotein produced in the kidney of sticklebacks during the breeding season and is subsequently secreted into the urinary bladder from where it is employed for nest building. Since the production of the protein has been shown to be under androgenic control, spiggin has been suggested to be a useful biomarker for androgenic substances in the environment. In this study, two polyclonal spiggin antibodies based on synthetic peptides and one polyclonal antibody directed against native spiggin have been characterized. The antibodies ability to identify spiggin was investigated by quantitative immunoassay. For both peptide antibodies the quantification range was determined to be between 1 and 80 ng spiggin and determination of renal spiggin levels from immature and mature males displayed a 15-fold increase in total spiggin content of the kidney resulting in a 6-fold increase in male kidney weight due to hypertrophy. The kidney somatic index (KSI) was found to correlate well with the total renal spiggin content and therefore it appears that KSI in sticklebacks could be used as an initial method to identify substances displaying androgenic effects. Furthermore, western blot analysis revealed that the polyclonal antibodies recognize different spiggin isoforms and that spiggin can be detected in the urinary bladder and kidney of both males and female sticklebacks. In order to develop a quantitative detection method for native spiggin it is necessary to produce a standard that can be used in a bioassay. Due to the adhesive and polymerization characteristics of spiggin the protein is difficult to use as a standard in bioassays. So far spiggin has been shown to exist in at least 14 isoforms, all of which contain polymerization domains. To overcome the solubility problem we have produced recombinant spiggin gamma, with only one polymerization domain, that can be expressed in E. coli. Western blot analysis demonstrated that the polyclonal antibodies were able to detect recombinant spiggin gamma protein in bacterial cell lysate, suggesting that it may be developed into a useful source of standard spiggin to be used for quantitative determination of androgen induced spiggin production in sticklebacks.

  • 3.
    Blanc, Mélanie
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kärrman, Anna
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Kukučka, Petr
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Keiter, Steffen
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Mixture-specific gene expression in zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonic acid (PFOS), perfluorohexanoic acid (PFHxA) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB126)2017Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 590-591, s. 249-257Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Perfluorooctane sulfonic acid (PFOS) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) are persistent organic pollutants of high concern because of their environmental persistence, bioaccumulation and toxic properties. Besides, the amphiphilic properties of fluorinated compounds such as PFOS and perfluorohexanoic acid (PFHxA) suggest a role in increasing cell membrane permeability and solubilizing chemicals. The present study aimed at investigating whether PFOS and PFHxA are capable of modifying the activation of PCB126 toxicity-related pathways. For this purpose, zebrafish embryos were exposed in semi-static conditions to 7.5 μg/L of PCB126 alone, in the presence of 25 mg/L of PFOS, 15.7 mg/L of PFHxA or in the presence of both PFOS and PFHxA. Quantitative PCR was performed on embryos aged from 24 h post fertilization (hpf) to 96 hpf to investigate expression changes of genes involved in metabolism of xenobiotics (ahr2, cyp1a), oxidative stress (gpx1a, tp53), lipids metabolism (acaa2, osbpl1a), and epigenetic mechanisms (dnmt1, dnmt3ba). Cyp1a and ahr2 expression were significantly induced by the presence of PCB126. However, after 72 and 78 h of exposure, induction of cyp1a expression was significantly lower when embryos were co-exposed to PCB126 + PFOS + PFHxA when compared to PCB126-exposed embryos. Significant upregulation of gpx1a occurred after exposure to PCB126 + PFHxA and to PCB126 + PFOS + PFHxA at 30 and 48 hpf. Besides, embryos appeared more sensitive to PCB126 + PFOS + PFHxA at 78 hpf: acaa2 and osbpl1a were significantly downregulated; dnmt1 was significantly upregulated. While presented as environmentally safe, PFHxA demonstrated that it could affect gene expression patterns in zebrafish embryos when combined to PFOS and PCB126, suggesting that such mixture may increase PCB126 toxicity. This is of particular relevance since PFHxA is persistent and still being ejected into the environment. Moreover, it provides additional information as to the importance to integrate mixture effects of chemicals in risk assessment and biomonitoring frameworks.

  • 4.
    Blanc, Mélanie
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Rüegg, Joëlle
    Institute for Environmental Medicine, Karolinska Institutet, Solna, Sweden.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Keiter, Steffen
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Environmental chemicals differentially affect epigenetic-related mechanisms in the zebrafish liver (ZF-L) cell line and in zebrafish embryos2019Ingår i: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 215, artikel-id 105272Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A number of chemicals have been shown to affect epigenetic patterning and functions. Since epigenetic mechanisms regulate transcriptional networks, epigenetic changes induced by chemical exposure can represent early molecular events for long-term adverse physiological effects. Epigenetics has thus appeared as a research field of major interest within (eco)toxicological sciences. The present study aimed at measuring effects on epigenetic-related mechanisms of selected environmental chemicals (bisphenols, perfluorinated chemicals, methoxychlor, permethrin, vinclozolin and coumarin 47) in zebrafish embryos and liver cells (ZFL). Transcription of genes related to DNA methylation and histone modifications was measured and global DNA methylation was assessed in ZFL cells using the LUMA assay. The differences in results gathered from both models suggest that chemicals affect different mechanisms related to epigenetics in embryos and cells. In zebrafish embryos, exposure to bisphenol A, coumarin 47, methoxychlor and permethrin lead to significant transcriptional changes in epigenetic factors suggesting that they can impact early epigenome reprogramming related to embryonic development. In ZFL cells, significant transcriptional changes were observed upon exposure to all chemicals but coumarin 47; however, only perfluorooctane sulfonate induced significant effects on global DNA methylation. Notably, in contrast to the other tested chemicals, perfluorooctane sulfonate affected only the expression of the histone demethylase kdm5ba. In addition, kdm5ba appeared as a sensitive gene in zebrafish embryos as well. Taken together, the present results suggest a role for kdm5ba in regulating epigenetic patterns in response to chemical exposure, even though mechanisms remain unclear. To confirm these findings, further evidence is required regarding changes in site-specific histone marks and DNA methylation together with their long-term effects on physiological outcomes.

  • 5.
    Delbro, Dick
    et al.
    Örebro universitet, Institutionen för medicinska vetenskaper.
    Hallsberg, Lena
    Department of Surgery, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Peeker, Ralph
    Department of Urology, Institute of Clinical Sciences, Sahlgrenska Academy. University of Gothenburg, Gothenburg, Sweden.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Fall, Magnus
    Department of Urology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Godtman, Rebecka Arnsrud
    Department of Urology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    The extracellular matrix-degrading protein ADAMTS5 is expressed in the nuclei of urothelial cells in healthy rats2018Ingår i: Scandinavian journal of urology, ISSN 2168-1805, E-ISSN 2168-1813, Vol. 52, nr 2, s. 139-142Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: The aim of this study was to investigate whether protein expression of the extracellular matrix-degrading protease ADAMTS5 can be demonstrated in the urinary bladder of healthy rats, and, if so, to determine the localization of this enzyme.

    MATERIALS AND METHODS: The experiments were conducted with eight inbred male Sprague-Dawley rats. Immunohistochemistry was used to investigate the expression of ADAMTS5 in the urinary bladder. Negative controls were established by either excluding the primary antibody or applying the antibody after it had been preabsorbed with its immunogenic peptide. Confocal microscopy was used to visualize the distribution of ADAMTS5 in the urinary bladder tissue.

    RESULTS: Immunoreactivity for ADAMTS5 was demonstrated in the urothelium and in the detrusor. This expression was localized not only in the cytoplasm, but also in the nuclei. Confocal microscopy corroborated these findings.

    CONCLUSION: Expression of ADAMTS5 was demonstrated in the cytoplasm as well as in the nuclei of the urothelium and detrusor cells, suggesting that it may play a role at the transcriptional level.

  • 6. dos Santos, Daniel
    et al.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap.
    Strid, Åke
    Örebro universitet, Institutionen för naturvetenskap.
    Eriksson, Leif A.
    Örebro universitet, Institutionen för naturvetenskap.
    Modelling Pisum sativum short-chain dehydrogenase/reductase enzymesManuskript (Övrigt vetenskapligt)
  • 7.
    Geng, Dawei
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Musse, Ayan Au
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Wigh, Viktoria
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Carlsson, Cecilia
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Engwall, Magnus
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Oresic, Matej
    Örebro universitet, Institutionen för medicinska vetenskaper. Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Hyötyläinen, Tuulia
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Effect of perfluorooctanesulfonic acid (PFOS) on the liver lipid metabolism of the developing chicken embryo2019Ingår i: Ecotoxicology and Environmental Safety, ISSN 0147-6513, E-ISSN 1090-2414, Vol. 170, s. 691-698Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Perfluorooctanesulfonate (PFOS) is a well-known contaminant in the environment and it has shown to disrupt multiple biological pathways, particularly those related with lipid metabolism. In this study, we have studied the impact of in ovo exposure to PFOS on lipid metabolism in livers in developing chicken embryos using lipidomics for detailed characterization of the liver lipidome. We used an avian model (Gallus gallus domesticus) for in ovo treatment at two levels of PFOS. The lipid profile of the liver of the embryo was investigated by ultra-high performance liquid chromatography combined with quadrupole-time-of-flight mass spectrometry and by gas chromatography mass spectrometry. Over 170 lipids were identified, covering phospholipids, ceramides, di- and triacylglycerols, cholesterol esters and fatty acid composition of the lipids. The PFOS exposure caused dose dependent changes in the lipid levels, which included upregulation of specific phospholipids associated with the phosphatidylethanolamine N-methyltransferase (PEMT) pathway, triacylglycerols with low carbon number and double bond count as well as of lipotoxic ceramides and diacylglycerols. Our data suggest that at lower levels of exposure, mitochondrial fatty acid β-oxidation is suppressed while the peroxisomal fatty acid β -oxidation is increased. At higher doses, however, both β -oxidation pathways are upregulated.

  • 8. Hossain, Mohammad Sorowar
    et al.
    Larsson, Anders
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Olsson, Per-Erik
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Orban, Laszlo
    Zebrafish androgen receptor: isolation, molecular, and biochemical characterization2008Ingår i: Biology of Reproduction, ISSN 0006-3363, E-ISSN 1529-7268, Vol. 78, nr 2, s. 361-369Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Androgens play an important role in male sexual differentiation and development. They exert their function by binding to and activating the androgen receptor (Ar), a member of the steroid hormone receptor superfamily. Here, we report on the isolation and characterization of zebrafish Ar. The complete transcript of zebrafish ar is 5.3 kb long encoding a putative polypeptide of 868 amino acids. Our experimental and bioinformatic analysis has found a single ar locus in zebrafish. Phylogenetic analysis using the ligand-binding domain showed that the zebrafish Ar clustered with its cyprinid orthologs to form a separate group, which was closer to the beta clade than to the alpha clade. Tissue-specific expression analysis revealed that the ar mRNA was expressed ubiquitously in all adult tissues tested, with sexually dimorphic expression in the gonad and muscle. While the ar transcript was maternally deposited into the embryo, signs of zygotic expression could be detected as early as 24 h after fertilization, and the expression level increased substantially afterwards. When analyzed during gonad development, the expression level of ar mRNA at 4 wk after fertilization was similar in both developing gonads but later became higher in the transforming testis, suggesting a potential role during male gonad differentiation. We also combined theoretical modeling with in vitro experiments to show that the zebrafish Ar is preferentially activated by 11-ketotestosterone.

  • 9.
    Jacobsen, Annette V.
    et al.
    School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, Australia; The Life Science Center, School of Science and Technology, Örebro University, Örebro, Sweden; The Walter and Eliza Hall Institute, Department of Medical Biology, The University of Melbourne, Parkville, Australia.
    Nordén, Marcus
    MTM Research Center, School of Science and Technology, Örebro University, Örebro, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.
    Engwall, Magnus
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Effects of perfluorooctane sulfonate on genes controlling hepatic fatty acid metabolism in livers of chicken embryos2018Ingår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 25, nr 23, s. 23074-23081Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Per- and polyfluoroalkyl substances (PFAS) are synthetic surfactants with a wide variety of applications; however, due to their stability, they are particularly resistant to degradation and, as such, are classed as persistent organic pollutants. Perfluorooctane sulfonate (PFOS) is one such PFAS that is still detectable in a range of different environmental settings, despite its use now being regulated in numerous countries. Elevated levels of PFOS have been detected in various avian species, and the impact of this on avian health is of interest when determining acceptable levels of PFOS in the environment. Due to its similarities to naturally occurring fatty acids, PFOS has potential to disrupt a range of biological pathways, particularly those associated with lipid metabolism, and this has been shown in various species. In this study, we have investigated how in ovo exposure to environmentally relevant levels of PFOS affects expression of genes involved in lipid metabolism of developing chicken embryos. We have found a broad suppression of transcription of genes involved in fatty acid oxidation and PPAR-mediated transcription with more significant effects apparent at lower doses of PFOS. These results highlight the need for more research investigating the biological impacts of low levels of PFAS to properly inform environmental policy governing their regulation.

  • 10.
    Jacobsen, Annette
    et al.
    School of Science and Technology, Örebro University, Örebro, Sweden; School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, Australia.
    Yemaneab, Bisrat
    School of Science and Technology, Örebro University, Örebro, Sweden.
    Jass, Jana
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Reference gene selection for qPCR Is dependent on cell type rather than treatment in colonic and vaginal human epithelial cell lines2014Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 12, s. e115592-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ability of commensal bacteria to influence gene expression in host cells under the influence of pathogenic bacteria has previously been demonstrated, however the extent of this interaction is important for understanding how bacteria can be used as probiotics. Real-time quantitative polymerase chain reaction is the most sensitive tool for evaluating relative changes to gene expression levels. However as a result of its sensitivity an appropriate method of normalisation should be used to account for any variation incurred in preparatory experimental procedures. These variations may result from differences in the amount of starting material, quality of extracted RNA, or in the efficiency of the reverse transcriptase or polymerase enzymes. Selection of an endogenous control gene is the preferred method of normalisation, and ideally a proper validation of the gene's appropriateness for the study in question should be performed. In this study we used quantitative polymerase chain reaction data and applied four different algorithms (geNorm, BestKeeper, NormFinder, and comparative ΔCq) to evaluate eleven different genes as to their suitability as endogenous controls for use in studies involving colonic (HT-29) and vaginal (VK2/E6E7) human mucosal epithelial cells treated with probiotic and pathogenic bacteria. We found phosphoglycerate kinase 1 to be most appropriate for HT-29 cells, and ribosomal protein large P0 to be the best choice for VK2/E6E7 cells. We also showed that use of less stable reference genes can lead to less accurate quantification of expression levels of gene of interest (GOI) and also can result in decreased statistical significance for GOI expression levels when compared to control. Additionally, we found the cell type being analysed had greater influence on reference gene selection than the treatment performed. This study provides recommendations for stable endogenous control genes for use in further studies involving colonic and vaginal cell lines after bacterial challenge.

  • 11.
    Karlsson, Mattias
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Lam, Simon
    Department of Microbiology and Immunology, University of Western Ontario and The Lawson Health Research Institute, London ON, Canada.
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Jass, Jana
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Released substances from lactobacilli influence immune responses in human epithelial cells2010Ingår i: Abstracts of the 3rd Swedish-Hellenic Life Sciences Research Conference, Athens, March 25-27, 2010 / [ed] Fragiskos Kolisis, Nikolaos Venizelos, 2010, s. 367-368Konferensbidrag (Refereegranskat)
  • 12.
    Karlsson, Mattias
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Khalaf, Hazem
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Olsson, Per-Erik
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Jass, Jana
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Substances released from probiotic Lactobacillus rhamnosus GR-1 potentiate NF-κB activity in Escherichia coli-stimulated urinary bladder cells2012Ingår i: FEMS Immunology and Medical Microbiology, ISSN 0928-8244, E-ISSN 1574-695X, Vol. 66, nr 2, s. 147-156Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Lactobacillus rhamnosus GR-1 is a probiotic bacterium used to maintain urogenital health. The putative mechanism for its probiotic effect is by modulating the host immunity. Urinary tract infections (UTI) are often caused by uropathogenic Escherichia coli that frequently evade or suppress immune responses in the bladder and can target pathways, including nuclear factor-kappaB (NF-κB). We evaluated the role of L. rhamnosus GR-1 on NF-κB activation in E. coli-stimulated bladder cells. Viable L. rhamnosus GR-1 was found to potentiate NF-κB activity in E. coli-stimulated T24 bladder cells, whereas heat-killed lactobacilli demonstrated a marginal increase in NF-κB activity. Surface components released by trypsin- or LiCl treatment, or the resultant heat-killed shaved lactobacilli, had no effect on NF-κB activity. Isolation of released products from L. rhamnosus GR-1 demonstrated that the induction of NF-κB activity was owing to released product(s) with a relatively large native size. Several putative immunomodulatory proteins were identified, namely GroEL, elongation factor Tu and NLP/P60. GroEL and elongation factor Tu have previously been shown to elicit immune responses from human cells. Isolating and using immune-augmenting substances produced by lactobacilli is a novel strategy for the prevention or treatment of UTI caused by immune-evading E. coli.

  • 13.
    Karlsson, Mattias
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Reid, Gregor
    Department of Microbiology and Immunology, University of Western Ontario, London ON, Canada.
    Jass, Jana
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Lactobacillus rhamnosus GR-1 enhances NF-kappaB activation in Escherichia coli-stimulated urinary bladder cells through TLR42012Ingår i: BMC Microbiology, ISSN 1471-2180, E-ISSN 1471-2180, Vol. 12, s. 15-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Epithelial cells of the urinary tract recognize pathogenic bacteria through pattern recognition receptors on their surface, such as toll-like receptors (TLRs), and mount an immune response through the activation of the NF-kappaB pathway. Some uropathogenic bacteria can subvert these cellular responses, creating problems with how the host eliminates pathogens. Lactobacillus is a genus of lactic acid bacteria that are part of the microbiota and consist of many probiotic strains, some specifically for urogenital infections. Immunomodulation has emerged as an important mode of action of probiotic and commensal lactobacilli and given the importance of epithelial cells, we evaluated the effect of the urogenital probiotic Lactobacillus rhamnosus GR-1 on epithelial immune activation.

    Results: Immune activation through the NF-kappaB pathway was initiated by stimulation of T24 urothelial cells with heat-killed Escherichia coli and this was further potentiated when cells were co-cultured with live L. rhamnosus GR-1. Heat-killed lactobacilli were poor activators of NF-kappaB. Concomitant stimulation of bladder cells with E. coli and L. rhamnosus GR 1 increased the levels of the pro-inflammatory cytokine TNF, whereas IL-6 and CXCL8 levels were reduced. Another probiotic, L. rhamnosus GG, was also able to potentiate NF-kappaB in these cells although at a significantly reduced level compared to the GR 1 strain. The transcript numbers and protein levels of the lipopolysaccharide receptor TLR4 were significantly increased after co-stimulation with E. coli and lactobacilli compared to controls. Furthermore, inhibition of TLR4 activation by polymixin B completely blocked the lactobacilli potentiation of NF-kappaB.

    Conclusions: The immunological outcome of E. coli challenge of bladder cells was influenced by probiotic L. rhamnosus GR 1, by enhancing the activation of NF-kappaB and TNF release. Thus the urogenital probiotic L. rhamnosus GR-1 modulated the activation of the NF-kappaB through increased levels of TLR4 on the bladder cells and altered subsequent release of cytokines from urothelial cells. By influencing immunological factors such as TLR4, important in the process of fighting pathogens, lactobacilli could facilitate pathogen recognition and infection clearance.

  • 14.
    Khalaf, Hazem
    et al.
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Nakka, Sravya Sowdamini
    Örebro universitet, Institutionen för hälsovetenskap och medicin. PEAS Institut AB, Söderleden 1, Linköping.
    Sandén, Camilla
    Division of Molecular Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
    Svärd, Anna
    Division of Molecular Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
    Hultenby, Kjell
    Division of Clinical Research Centre, Department of Laboratory Medicine, Karolinska.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Aili, Daniel
    PEAS Institut AB, Söderleden 1, Linköping.
    Bengtsson, Torbjörn
    Örebro universitet, Institutionen för läkarutbildning.
    Antibacterial effects of lactobacillus and bacteriocin NC8 αβ on the periodontal pathogen Porphyromonas gingivalisManuskript (preprint) (Övrigt vetenskapligt)
  • 15.
    Khalaf, Hazem
    et al.
    Örebro universitet, Institutionen för medicinska vetenskaper.
    Nakka, Sravya Sowdamini
    Örebro universitet, Institutionen för medicinska vetenskaper. PEAS Institut AB, Linköping, Sweden.
    Sandén, Camilla
    Division of Molecular Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
    Svärd, Anna
    Division of Molecular Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
    Hultenby, Kjell
    Division of Clinical Research Centre, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Aili, Daniel
    Division of Molecular Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, Sweden.
    Bengtsson, Torbjörn
    Örebro universitet, Institutionen för medicinska vetenskaper.
    Antibacterial effects of Lactobacillus and bacteriocin PLNC8 αβ on the periodontal pathogen Porphyromonas gingivalis2016Ingår i: BMC Microbiology, ISSN 1471-2180, E-ISSN 1471-2180, Vol. 16, nr 1, artikel-id 188Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: The complications in healthcare systems associated with antibiotic-resistant microorganisms have resulted in an intense search for new effective antimicrobials. Attractive substances from which novel antibiotics may be developed are the bacteriocins. These naturally occurring peptides are generally considered to be safe and efficient at eliminating pathogenic bacteria. Among specific keystone pathogens in periodontitis, Porphyromonas gingivalis is considered to be the most important pathogen in the development and progression of chronic inflammatory disease. The aim of the present study was to investigate the antimicrobial effects of different Lactobacillus species and the two-peptide bacteriocin PLNC8 αβ on P. gingivalis.

    Results: Growth inhibition of P. gingivalis was obtained by viable Lactobacillus and culture media from L. plantarum NC8 and 44048, but not L. brevis 30670. The two-peptide bacteriocin from L. plantarum NC8 (PLNC8 αβ) was found to be efficient against P. gingivalis through binding followed by permeabilization of the membranes, using Surface plasmon resonance analysis and DNA staining with Sytox Green. Liposomal systems were acquired to verify membrane permeabilization by PLNC8 αβ. The antimicrobial activity of PLNC8 αβ was found to be rapid (1 min) and visualized by TEM to cause cellular distortion through detachment of the outer membrane and bacterial lysis.

    Conclusion: Soluble or immobilized PLNC8 αβ bacteriocins may be used to prevent P. gingivalis colonization and subsequent pathogenicity, and thus supplement the host immune system against invading pathogens associated with periodontitis.

  • 16.
    Krivospitskaya, Olesya
    et al.
    Örebro universitet, Hälsoakademin.
    Elmabsout, Ali Ateia
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Sundman, Eva
    Department of Anesthesiology, Surgical Services and Intensive Care Medicine, Karolinska University Hospital Solna, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden.
    Söderström, Leif A.
    Department of Anesthesiology, Surgical Services and Intensive Care Medicine, Karolinska University Hospital Solna, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden; Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
    Ovchinnikova, Olga
    Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
    Gidlöf, Andreas C.
    Department of Anesthesiology, Surgical Services and Intensive Care Medicine, Karolinska University Hospital Solna, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Norata, Giuseppe Danilo
    Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Pharmacological Sciences University of Milan, Milan, Italy.
    Samnegård, Ann
    Division of Cardiovascular Medicine, Department of Clinical Sciences, Danderyd Hospital, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden.
    Törmä, Hans
    Department of Medical Sciences/Dermatology, Uppsala University, Uppsala, Sweden.
    Abdel-Halim, Samy M.
    Division of Respiratory Medicine and Allergology, Department of Clinical Sciences, Danderyd Hospital, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden.
    Jansson, Jan-Håkan
    Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden; Department of Medicine, Skellefteå Hospital, Skellefteå, Sweden.
    Eriksson, Per
    Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
    Sirsjö, Allan
    Örebro universitet, Institutionen för hälsovetenskap och medicin.
    Olofsson, Peder S.
    Department of Anesthesiology, Surgical Services and Intensive Care Medicine, Karolinska University Hospital Solna, Stockholm, Sweden; Karolinska Institutet, Stockholm, Sweden; Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden; Laboratory of Biomedical Science, The Feinstein Institute for Medical Research, North Shore–Long Island Jewish (LIJ) Health System, New York, United States of America.
    A CYP26B1 polymorphism enhances retinoic acid catabolism and may aggravate atherosclerosis2012Ingår i: Molecular medicine (Cambridge, Mass. Print), ISSN 1076-1551, E-ISSN 1528-3658, Vol. 18, nr 1, s. 712-718Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    All-trans retinoic acid, controlled by CYP26 enzymes, potentially has beneficial effects in atherosclerosis treatment. This study investigates CYP26B1 in atherosclerosis and effects of a genetic polymorphism in CYP26B1 on retinoid catabolism. We found that CYP26B1 mRNA was induced by retinoic acid in human atherosclerotic arteries and CYP26B1 and the macrophage marker CD68 co-localized in human atherosclerotic lesions. In mice, Cyp26B1 mRNA was higher in atherosclerotic than normal arteries. Databases were queried for non-synonymous CYP26B1 SNPs and rs2241057 selected for further studies. Constructs of the CYP26B1 variants were created and used for production of purified proteins and transfection of macrophage-like cells. The minor variant catabolized retinoic acid with significantly higher efficiency, indicating that rs2241057 is functional and suggesting reduced retinoid availability in tissues with the minor variant. rs2241057 was investigated in a Stockholm Coronary Atherosclerosis Risk Factor (SCARF) subgroup. The minor allele was associated with slightly larger lesions as determined by angiography. In summary, this study identifies the first CYP26B1 polymorphism that alters CYP26B1 capacity to metabolize retinoic acid. CYP26B1 was expressed in macrophage-rich areas of human atherosclerotic lesions, induced by retinoic acid and increased in murine atherosclerosis. Taken together, the results indicate that CYP26B1 capacity is genetically regulated and suggest that local CYP26B1 activity may influence atherosclerosis.

  • 17.
    Lindh, Ingrid
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Kalbina, Irina
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Hedberg, Sara Thulin
    Scherbak, Nikolai
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Sävenstrand, Helena
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Bråve, Andreas
    Hinkula, Jorma
    Strid, Åke
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Andersson, Sören
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Feeding of mice with Arabidopsis thaliana expressing the HIV-1 subtype C p24 antigen gives rise to systemic immune responses2008Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 116, nr 11, s. 985-994Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Development of transgenic edible plants, to be used as production, storage and delivery systems for recombinant vaccine antigens, is a promising strategy to obtain cost effective vaccines against infectious diseases, not the least for use in developing countries. Therefore, we used Agrobacterium tumefaciens-mediated gene transfer to introduce the p24 gag gene encoding the nucleocapsid protein from HIV-1 subtype C into the Arabidopsis thaliana plant genome. Eighteen plant lines were confirmed positive for the p24 gene by PCR, four of these lines showed an apparent homozygous phenotype when grown on selective medium and these lines also showed transcription of the p24 gene into its corresponding mRNA. The mRNA in all four cases generated the p24 protein in plants, as verified by western blot analysis. The plants were shown to contain between 0.2 µg and 0.5 µg p24 protein per g of fresh tissue. Analysis of the localisation of the p24 protein showed that stem tissue contained the largest amount of protein, more than twice as much as leaf tissue, whereas no p24 protein was detected in roots. By using Southern blotting, we found that 4, 2-3, 2 and 1 T-DNA insertion events took place in the four lines 1, 2, 7, and 10, respectively. The genetic insertions of line 1 were stable from the T1 to the T4 generation and gave rise to the p24 protein in all cases, as verified by western blotting. In mice fed with fresh transgenic A. thaliana (line 10), anti-gag IgG was obtained in serum after a booster injection with recombinant p37Gag. No immune response was observed after equal booster injection of untreated mice or mice fed with A. thaliana WT plants.

  • 18.
    Scherbak, Nikolai
    Örebro universitet, Institutionen för naturvetenskap.
    Characterization of stress-inducible short-chain dehydrogenases/reductases (SDR) in plants: study of a novel small protein family from Pisum sativum (pea)2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In pea (Pisum sativum), the short-chain alcohol dehydrogenase-like protein (SAD) gene family consists of at least three members (SAD-A, -B, and -C). The SAD genes are transiently expressed in plants after short exposures to ultraviolet-B radiation, which in turn leads to formation of SAD protein in leaf and stem tissue upon prolonged irradiation. SAD gene expression is also seen as a result of wounding stress.

    The recombinant SAD-C protein (which was the most highly over-expressed isoform in Escherichia coli of the isoforms) was shown to be a tetramer that probably consists of a dimer of dimers and which possesses quinone-reducing capability. The enzyme shows approximately the same NADH- and NADPH-dependent activity with 2,5- and 2,6-dimethylbenzoquinone and menadione as substrates.

    Western blotting and immunohistochemistry (IHC) shows that the SAD protein is present to a smaller or larger extent in all the different pea tissues examined. Environmental stress such as UV-B radiation clearly increases the content of SAD in leaf and stem tissue but not in roots. This indicates that increased expression of the SAD genes, as a result of UV-B exposure, is limited to the exposed tissue. This is substantiated by the heterologous GUS expression from the pea SAD-C promoter in Arabidopsis during wounding. Only the wound site and the vicinal tissue show transcription from this promoter. In non-stressed tissue (as well as in UV-B-stressed leaves and stem), SAD predominantly occurred in epidermal or sub-epidermal cells as judged by IHC. The protoderm of the pea seed cotyledonary axis contains the most heavily stained cells. This indicates a possible role for the SAD protein in development as well as in protection against environmental stress. Also, discrete staining was obtained in particular cell types of the ovary.

    To be able to understand the biochemical and physiological role of the SAD enzyme, an in silico modeling study of the SAD protein structure was performed. The simulations of our SAD protein, as well as of related proteins with known crystal structure (3alfa,20beta-hydroxysteroid dehydrogenase and secoisolariciresinol dehydrogenase), allowed us to obtain an energy-minimized structure for the monomeric SAD as well as important data on the cofactor interaction in the active site.

    Crystallization of recombinant SAD-C has been performed. The needle-like crystals, which diffract to 3.5Å, contain probably eight monomers in the asymmetric unit, presumably containing a pair of tetramers.

    SAD enhances the reduction rates of quinones with NADH. However, NADH can also accomplish reduction of certain quinones non-enzymatically. Both theoretical calculations and experimental techniques were used to elucidate the structural and electronic pre-requisites for this non-enzymatic quinone reduction.

    Delarbeten
    1. Plant SAD proteins: characterization of the tetrameric Pisum sativum protein
    Öppna denna publikation i ny flik eller fönster >>Plant SAD proteins: characterization of the tetrameric Pisum sativum protein
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nationell ämneskategori
    Biokemi och molekylärbiologi Biologiska vetenskaper
    Forskningsämne
    Biokemi; Biologi
    Identifikatorer
    urn:nbn:se:oru:diva-2939 (URN)
    Tillgänglig från: 2005-11-11 Skapad: 2005-11-11 Senast uppdaterad: 2017-10-18Bibliografiskt granskad
    2. Non-enzymatic oxidation of NADH by quinones
    Öppna denna publikation i ny flik eller fönster >>Non-enzymatic oxidation of NADH by quinones
    2005 (Engelska)Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 414, nr 1-3, s. 243-247Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Non-enzymatic oxidation of NADH by a large number of different quinones has been explored both theoretically and experimentally. It is concluded that the smaller benzo- and naphtho-quinones are capable of oxidising NADH in aqueous solution, whereas the larger anthraquinone is not. The mechanisms of stepwise electron and proton transfers are explored, and ruled out in favour of direct hydride transfer. For menadione (2-methyl-1,4-naphthoquinone), no reaction is observed experimentally; theoretically we find that there is a very close balance between the energetic cost of hydride removal from NADH and the energy gain of formation of the menadione semiquinone radical anion.

    Nationell ämneskategori
    Biologiska vetenskaper Biokemi och molekylärbiologi
    Forskningsämne
    Biologi; Biokemi
    Identifikatorer
    urn:nbn:se:oru:diva-2940 (URN)10.1016/j.cplett.2005.08.067 (DOI)
    Tillgänglig från: 2005-11-11 Skapad: 2005-11-11 Senast uppdaterad: 2017-12-14Bibliografiskt granskad
    3. Tissue distribution of short-chain alcohol dehydrogenase (SAD) proteins in pea (Pisum sativum) in the absence and presence of UV-B stress, and heterologous stress-induced expression from the SAD promoter
    Öppna denna publikation i ny flik eller fönster >>Tissue distribution of short-chain alcohol dehydrogenase (SAD) proteins in pea (Pisum sativum) in the absence and presence of UV-B stress, and heterologous stress-induced expression from the SAD promoter
    Visa övriga...
    (Engelska)Manuskript (preprint) (Övrigt vetenskapligt)
    Nationell ämneskategori
    Biokemi och molekylärbiologi Biologiska vetenskaper
    Forskningsämne
    Biokemi; Biologi
    Identifikatorer
    urn:nbn:se:oru:diva-2941 (URN)
    Tillgänglig från: 2005-11-11 Skapad: 2005-11-11 Senast uppdaterad: 2017-10-18Bibliografiskt granskad
    4. Modelling Pisum sativum short-chain dehydrogenase/reductase enzymes
    Öppna denna publikation i ny flik eller fönster >>Modelling Pisum sativum short-chain dehydrogenase/reductase enzymes
    (Engelska)Manuskript (Övrigt vetenskapligt)
    Nationell ämneskategori
    Biologiska vetenskaper
    Forskningsämne
    Biologi
    Identifikatorer
    urn:nbn:se:oru:diva-2942 (URN)
    Tillgänglig från: 2005-11-11 Skapad: 2005-11-11 Senast uppdaterad: 2017-10-18Bibliografiskt granskad
  • 19.
    Scherbak, Nikolai
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Ala-Häiväla, Anneli
    Brosché, Mikael
    Helsingfors Universitet, Helsingfors, Finland.
    Böwer, Nathalie
    Strid, Hilja
    Örebro universitet, Hälsoakademin.
    Gittins, John R.
    University of Southampton, Southampton, UK.
    Grahn, Elin M.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Eriksson, Leif A.
    National University of Ireland, Galway, Ireland.
    Strid, Åke
    Örebro universitet, Akademin för naturvetenskap och teknik.
    The pea SAD short-chain dehydrogenase/reductase: quinone reduction, tissue distribution, and heterologous expression2011Ingår i: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 155, nr 4, s. 1839-1850Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one- or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placental surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis thaliana), which confirmed that the inducibility of its expression is regulated at the transcriptional level.

  • 20.
    Scherbak, Nikolai
    et al.
    Örebro universitet, Institutionen för naturvetenskap.
    Ala-Häivälä, Anneli
    Gittins, John R.
    Brosché, Mikael
    Strid, Hilja
    Strid, Åke
    Örebro universitet, Institutionen för naturvetenskap.
    Tissue distribution of short-chain alcohol dehydrogenase (SAD) proteins in pea (Pisum sativum) in the absence and presence of UV-B stress, and heterologous stress-induced expression from the SAD promoterManuskript (preprint) (Övrigt vetenskapligt)
  • 21.
    Scherbak, Nikolai
    et al.
    Örebro universitet, Institutionen för naturvetenskap.
    Brosché, Mikael
    Ala-Häivälä, Anneli
    Olsson, Annika
    Enroth, Cristofer
    Örebro universitet, Institutionen för naturvetenskap.
    Eriksson, Leif A.
    Örebro universitet, Institutionen för naturvetenskap.
    Nilsson, Fredrik
    Strid, Åke
    Örebro universitet, Institutionen för naturvetenskap.
    Plant SAD proteins: characterization of the tetrameric Pisum sativum proteinManuskript (preprint) (Övrigt vetenskapligt)
  • 22.
    Scherbak, Nikolai
    et al.
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Brosché, Mikael
    Ala-Häivälä, Anneli
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Strid, Hilja
    Örebro universitet, Hälsoakademin.
    Öhrfelt, Annika
    Nilsson, Fredrik
    Strid, Åke
    Örebro universitet, Akademin för naturvetenskap och teknik.
    Expression of Pisum sativum SAD polypeptides in production hosts and in planta: Tetrameric organization of the protein2009Ingår i: Protein Expression and Purification, ISSN 1046-5928, E-ISSN 1096-0279, Vol. 63, nr 1, s. 18-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In Pisum sativum, the short-chain alcohol dehydrogenase-like protein (SAD) gene family consists of at least three members (SAD-A, -B, and -C). Expression of two of these genes (SAD-A and -C) in Escherichia coli or Pichia pastoris resulted in full-length soluble proteins. Purified SAD-A was used as antigen for antibody production in rabbits. With these antibodies the recombinant SAD-C protein (which was most highly expressed of the two isoforms) was shown to be a tetramer consisting of a dimer of dimers. The SAD genes are transiently expressed in plants by short exposures to ultraviolet-B radiation (UV-B), as judged by northern blotting. In turn, mRNA accumulation leads to formation of SAD protein in leaf and stem tissue upon prolonged UV-B irradiation.

  • 23.
    Scherbak, Nikolai
    et al.
    Örebro universitet, Institutionen för naturvetenskap.
    Strid, Åke
    Örebro universitet, Institutionen för naturvetenskap.
    Eriksson, Leif A.
    Örebro universitet, Institutionen för naturvetenskap.
    Non-enzymatic oxidation of NADH by quinones2005Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 414, nr 1-3, s. 243-247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Non-enzymatic oxidation of NADH by a large number of different quinones has been explored both theoretically and experimentally. It is concluded that the smaller benzo- and naphtho-quinones are capable of oxidising NADH in aqueous solution, whereas the larger anthraquinone is not. The mechanisms of stepwise electron and proton transfers are explored, and ruled out in favour of direct hydride transfer. For menadione (2-methyl-1,4-naphthoquinone), no reaction is observed experimentally; theoretically we find that there is a very close balance between the energetic cost of hydride removal from NADH and the energy gain of formation of the menadione semiquinone radical anion.

1 - 23 av 23
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