@article{SilwedelHuettenSpeeretal.2023, author = {Silwedel, Christine and H{\"u}tten, Matthias C. and Speer, Christian P. and H{\"a}rtel, Christoph and Haarmann, Axel and Henrich, Birgit and Tijssen, Maud P. M. and Alnakhli, Abdullah Ahmed and Spiller, Owen B. and Schlegel, Nicolas and Seidenspinner, Silvia and Kramer, Boris W. and Glaser, Kirsten}, title = {Ureaplasma-driven neonatal neuroinflammation: novel insights from an ovine model}, series = {Cellular and Molecular Neurobiology}, volume = {43}, journal = {Cellular and Molecular Neurobiology}, number = {2}, doi = {10.1007/s10571-022-01213-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-324285}, pages = {785-795}, year = {2023}, abstract = {Ureaplasma species (spp.) are considered commensals of the adult genitourinary tract, but have been associated with chorioamnionitis, preterm birth, and invasive infections in neonates, including meningitis. Data on mechanisms involved in Ureaplasma-driven neuroinflammation are scarce. The present study addressed brain inflammatory responses in preterm lambs exposed to Ureaplasma parvum (UP) in utero. 7 days after intra-amniotic injection of UP (n = 10) or saline (n = 11), lambs were surgically delivered at gestational day 128-129. Expression of inflammatory markers was assessed in different brain regions using qRT-PCR and in cerebrospinal fluid (CSF) by multiplex immunoassay. CSF was analyzed for UP presence using ureB-based real-time PCR, and MRI scans documented cerebral white matter area and cortical folding. Cerebral tissue levels of atypical chemokine receptor (ACKR) 3, caspases 1-like, 2, 7, and C-X-C chemokine receptor (CXCR) 4 mRNA, as well as CSF interleukin-8 protein concentrations were significantly increased in UP-exposed lambs. UP presence in CSF was confirmed in one animal. Cortical folding and white matter area did not differ among groups. The present study confirms a role of caspases and the transmembrane receptors ACKR3 and CXCR4 in Ureaplasma-driven neuroinflammation. Enhanced caspase 1-like, 2, and 7 expression may reflect cell death. Increased ACKR3 and CXCR4 expression has been associated with inflammatory central nervous system (CNS) diseases and impaired blood-brain barrier function. According to these data and previous in vitro findings from our group, we speculate that Ureaplasma-induced caspase and receptor responses affect CNS barrier properties and thus facilitate neuroinflammation.}, language = {en} } @article{KunzmannHuettenOttensmeieretal.2022, author = {Kunzmann, Steffen and H{\"u}tten, Matthias and Ottensmeier, Barbara and Kramer, Boris W. and Fehrholz, Markus}, title = {A20 is increased in fetal lung in a sheep LPS model of chorioamnionitis}, series = {Oxidative Medicine and Cellular Longevity}, volume = {2022}, journal = {Oxidative Medicine and Cellular Longevity}, doi = {10.1155/2022/6421419}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265869}, year = {2022}, abstract = {Chorioamnionitis is associated with an increased risk of preterm birth and aggravates adverse outcomes such as BPD. Development of BPD is associated with chronic inflammatory reactions and oxidative stress in the airways which may be antenatally initiated by chorioamnionitis. A20 is an immunomodulatory protein involved in the negative feedback regulation of inflammatory reactions and is a possible regulator protein in oxidative stress reactions. The influence of chorioamnionitis on A20 gene regulation in the fetal lung is unknown. We characterized the influence of LPS and proinflammatory cytokines on A20 expression in human lung endothelial (HPMEC-ST1.6R) and epithelial (A549) cells in vitro by real-time PCR and/or western blotting and used a sheep model of LPS-induced chorioamnionitis for in vivo studies. To study the functional role of A20, endogenous A20 was overexpressed in HPMEC-ST1.6R and A549 cells. LPS induced proinflammatory cytokines in HPMEC-ST1.6R and A549 cells. Both LPS and/or proinflammatory cytokines elevated A20 at transcriptional and translational levels. Intra-amniotic LPS transiently increased IL-1β, IL-6, IL-8, and TNF-α mRNA levels in fetal lamb lungs, associated with an increase in A20 mRNA and protein levels. Overexpression of A20 reduced proinflammatory cytokines in vitro. Repeated LPS exposure induced LPS tolerance for proinflammatory cytokines and A20 in vitro and in vivo. Antenatal inflammation induced a transient increase in proinflammatory cytokines in the preterm fetal lung. The expression of proinflammatory cytokines increased expression of A20. Elevated A20 may have a protective role by downregulating chorioamnionitis-triggered fetal lung inflammation. A20 may be a novel target for pharmacological interventions to prevent chorioamnionitis-induced airway inflammation and lung damage, which can result in BPD later in life.}, language = {en} } @article{WidowskiReynaertOpheldersetal.2021, author = {Widowski, Helene and Reynaert, Niki L. and Ophelders, Daan R. M. G. and H{\"u}tten, Matthias C. and Nikkels, Peter G. J. and Severens-Rijvers, Carmen A. H. and Cleutjens, Jack P. M. and Kemp, Matthew W. and Newnham, John P. and Saito, Masatoshi and Usuda, Haruo and Payne, Matthew S. and Jobe, Alan H. and Kramer, Boris W. and Delhaas, Tammo and Wolfs, Tim G. A. M.}, title = {Sequential Exposure to Antenatal Microbial Triggers Attenuates Alveolar Growth and Pulmonary Vascular Development and Impacts Pulmonary Epithelial Stem/Progenitor Cells}, series = {Frontiers in Medicine}, volume = {8}, journal = {Frontiers in Medicine}, issn = {2296-858X}, doi = {10.3389/fmed.2021.614239}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229695}, year = {2021}, abstract = {Perinatal inflammatory stress is strongly associated with adverse pulmonary outcomes after preterm birth. Antenatal infections are an essential perinatal stress factor and contribute to preterm delivery, induction of lung inflammation and injury, pre-disposing preterm infants to bronchopulmonary dysplasia. Considering the polymicrobial nature of antenatal infection, which was reported to result in diverse effects and outcomes in preterm lungs, the aim was to examine the consequences of sequential inflammatory stimuli on endogenous epithelial stem/progenitor cells and vascular maturation, which are crucial drivers of lung development. Therefore, a translational ovine model of antenatal infection/inflammation with consecutive exposures to chronic and acute stimuli was used. Ovine fetuses were exposed intra-amniotically to Ureaplasma parvum 42 days (chronic stimulus) and/or to lipopolysaccharide 2 or 7 days (acute stimulus) prior to preterm delivery at 125 days of gestation. Pulmonary inflammation, endogenous epithelial stem cell populations, vascular modulators and morphology were investigated in preterm lungs. Pre-exposure to UP attenuated neutrophil infiltration in 7d LPS-exposed lungs and prevented reduction of SOX-9 expression and increased SP-B expression, which could indicate protective responses induced by re-exposure. Sequential exposures did not markedly impact stem/progenitors of the proximal airways (P63+ basal cells) compared to single exposure to LPS. In contrast, the alveolar size was increased solely in the UP+7d LPS group. In line, the most pronounced reduction of AEC2 and proliferating cells (Ki67+) was detected in these sequentially UP + 7d LPS-exposed lambs. A similar sensitization effect of UP pre-exposure was reflected by the vessel density and expression of vascular markers VEGFR-2 and Ang-1 that were significantly reduced after UP exposure prior to 2d LPS, when compared to UP and LPS exposure alone. Strikingly, while morphological changes of alveoli and vessels were seen after sequential microbial exposure, improved lung function was observed in UP, 7d LPS, and UP+7d LPS-exposed lambs. In conclusion, although sequential exposures did not markedly further impact epithelial stem/progenitor cell populations, re-exposure to an inflammatory stimulus resulted in disturbed alveolarization and abnormal pulmonary vascular development. Whether these negative effects on lung development can be rescued by the potentially protective responses observed, should be examined at later time points.}, language = {en} } @article{WillemsUrlichsSeidenspinneretal.2012, author = {Willems, Coen H. M. P. and Urlichs, Florian and Seidenspinner, Silvia and Kunzmann, Steffen and Speer, Christian P. and Kramer, Boris W.}, title = {Poractant alfa (Curosurf (R)) increases phagocytosis of apoptotic neutrophils by alveolar macrophages in vivo}, series = {Respiratory Research}, volume = {13}, journal = {Respiratory Research}, number = {17}, doi = {10.1186/1465-9921-13-17}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130721}, year = {2012}, abstract = {Background: Clearance of apoptotic neutrophils in the lung is an essential process to limit inflammation, since they could become a pro-inflammatory stimulus themselves. The clearance is partially mediated by alveolar macrophages, which phagocytose these apoptotic cells. The phagocytosis of apoptotic immune cells by monocytes in vitro has been shown to be augmented by several constituents of pulmonary surfactant, e. g. phospholipids and hydrophobic surfactant proteins. In this study, we assessed the influence of exogenous poractant alfa (Curosurf (R)) instillation on the in vivo phagocytosis of apoptotic neutrophils by alveolar macrophages. Methods: Poractant alfa (200 mg/kg) was instilled intratracheally in the lungs of three months old adult male C57/Black 6 mice, followed by apoptotic neutrophil instillation. Bronchoalveloar lavage was performed and alveolar macrophages and neutrophils were counted. Phagocytosis of apoptotic neutrophils was quantified by determining the number of apoptotic neutrophils per alveolar macrophages. Results: Exogenous surfactant increased the number of alveolar macrophages engulfing apoptotic neutrophils 2.6 fold. The phagocytosis of apoptotic neutrophils was increased in the presence of exogenous surfactant by a 4.7 fold increase in phagocytosed apoptotic neutrophils per alveolar macrophage. Conclusions: We conclude that the anti-inflammatory properties of surfactant therapy may be mediated in part by increased numbers of alveolar macrophages and increased phagocytosis of apoptotic neutrophils by alveolar macrophages.}, language = {en} } @article{FehrholzBersaniKrameretal.2012, author = {Fehrholz, Markus and Bersani, Iliana and Kramer, Boris W. and Speer, Christian P. and Kunzmann, Steffen}, title = {Synergistic Effect of Caffeine and Glucocorticoids on Expression of Surfactant Protein B (SP-B) mRNA}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-77927}, year = {2012}, abstract = {Administration of glucocorticoids and caffeine is a common therapeutic intervention in the neonatal period, but possible interactions between these substances are still unclear. The present study investigated the effect of caffeine and different glucocorticoids on expression of surfactant protein (SP)-B, crucial for the physiological function of pulmonary surfactant. We measured expression levels of SP-B, various SP-B transcription factors including erythroblastic leukemia viral oncogene homolog 4 (ErbB4) and thyroid transcription factor-1 (TTF-1), as well as the glucocorticoid receptor (GR) after administering different doses of glucocorticoids, caffeine, cAMP, or the phosphodiesterase-4 inhibitor rolipram in the human airway epithelial cell line NCI-H441. Administration of dexamethasone (1 mM) or caffeine (5 mM) stimulated SP-B mRNA expression with a maximal of 38.8611.1-fold and 5.261.4-fold increase, respectively. Synergistic induction was achieved after coadministration of dexamethasone (1 mM) in combination with caffeine (10 mM) (206659.7-fold increase, p,0.0001) or cAMP (1 mM) (2136111-fold increase, p = 0.0108). SP-B mRNA was synergistically induced also by administration of caffeine with hydrocortisone (87.9639.0), prednisolone (154666.8), and betamethasone (12366.4). Rolipram also induced SP-B mRNA (64.9621.0-fold increase). We detected a higher expression of ErbB4 and GR mRNA (7.0- and 1.7-fold increase, respectively), whereas TTF-1, Jun B, c-Jun, SP1, SP3, and HNF-3a mRNA expression was predominantly unchanged. In accordance with mRNA data, mature SP-B was induced significantly by dexamethasone with caffeine (13.869.0-fold increase, p = 0.0134). We found a synergistic upregulation of SP-B mRNA expression induced by co-administration of various glucocorticoids and caffeine, achieved by accumulation of intracellular cAMP. This effect was mediated by a caffeinedependent phosphodiesterase inhibition and by upregulation of both ErbB4 and the GR. These results suggested that caffeine is able to induce the expression of SP-transcription factors and affects the signaling pathways of glucocorticoids, amplifying their effects. Co-administration of caffeine and corticosteroids may therefore be of benefit in surfactant homeostasis.}, subject = {Medizin}, language = {en} } @article{LaugFehrholzSchuetzeetal.2012, author = {Laug, Roderich and Fehrholz, Markus and Sch{\"u}tze, Norbert and Kramer, Boris W. and Krump-Konvalinkova, Vera and Speer, Christian P. and Kunzmann, Steffen}, title = {IFN-gamma and TNF-alpha synergize to inhibit CTGF expression in human lung endothelial cells}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-76253}, year = {2012}, abstract = {Connective tissue growth factor (CTGF/CCN2) is an angiogenetic and profibrotic factor, acting downstream of TGF-b, involved in both airway- and vascular remodeling. While the T-helper 1 (Th1) cytokine interferon-gamma (IFN-c) is well characterized as immune-modulatory and anti-fibrotic cytokine, the role of IFN-c in lung endothelial cells (LEC) is less defined. Tumour necrosis factor alpha (TNF-a) is another mediator that drives vascular remodeling in inflammation by influencing CTGF expression. In the present study we investigated the influence of IFN-c and TNF-a on CTGF expression in human LEC (HPMEC-ST1.6R) and the effect of CTGF knock down on human LEC. IFN-c and TNF-a down-regulated CTGF in human LEC at the promoter-, transcriptional- and translational-level in a dose- and time-dependent manner. The inhibitory effect of IFN-c on CTGF-expression could be almost completely compensated by the Jak inhibitor AG-490, showing the involvement of the Jak-Stat signaling pathway. Besides the inhibitory effect of IFN-c and TNF-a alone on CTGF expression and LEC proliferation, these cytokines had an additive inhibitory effect on proliferation as well as on CTGF expression when administered together. To study the functional role of CTGF in LEC, endogenous CTGF expression was down-regulated by a lentiviral system. CTGF silencing in LEC by transduction of CTGF shRNA reduced cell proliferation, but did not influence the anti-proliferative effect of IFN-c and TNF-a. In conclusion, our data demonstrated that CTGF was negatively regulated by IFN-c in LEC in a Jak/Stat signaling pathway-dependent manner. In addition, an additive effect of IFN-c and TNF-a on inhibition of CTGF expression and cell proliferation could be found. The inverse correlation between IFN-c and CTGF expression in LEC could mean that screwing the Th2 response to a Th1 response with an additional IFN-c production might be beneficial to avoid airway remodeling in asthma.}, subject = {Medizin}, language = {en} }