64 results on '"Ale-Agha N"'
Search Results
2. Molecular mechanisms of EGFR activation by carbon nanoparticles in lung epithelial cells
- Author
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Stöckmann, D, primary, Peuschel, H, additional, Sydlik, U, additional, Kroker, M, additional, Ale-Agha, N, additional, Jakob, S, additional, Haendeler, J, additional, Grether-Beck, S, additional, and Unfried, K, additional
- Published
- 2013
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3. [106] CD133+ HEPATIC STELLATE CELLS REPRESENT A NOVEL PROGENITOR CELL COMPARTMENT OF THE LIVER
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Kordes, C., primary, Sawitza, I., additional, Mueller-Marbach, A., additional, Ale-Agha, N., additional, Keitel, V., additional, Klonowski-Stumpe, H., additional, and Haeussinger, D., additional
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- 2007
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4. Non-Antioxidant Properties of Carotenoids
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Stahl, W., primary, Ale-Agha, N., additional, and Polidori, M.C., additional
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- 2002
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5. A new powdery mildew disease on Aesculus spp. introduced in Europe
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Ale-Agha, N, primary
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- 2000
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6. Aryl Hydrocarbon Receptor-Dependent and -Independent Pathways Mediate Curcumin Anti-Aging Effects
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Vanessa Brinkmann, Margherita Romeo, Lucie Larigot, Anne Hemmers, Lisa Tschage, Jennifer Kleinjohann, Alfonso Schiavi, Swantje Steinwachs, Charlotte Esser, Ralph Menzel, Sara Giani Tagliabue, Laura Bonati, Fiona Cox, Niloofar Ale-Agha, Philipp Jakobs, Joachim Altschmied, Judith Haendeler, Xavier Coumoul, Natascia Ventura, Heinrich Heine Universität Düsseldorf = Heinrich Heine University [Düsseldorf], Toxicité environnementale, cibles thérapeutiques, signalisation cellulaire (T3S - UMR_S 1124), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Leibniz Research Institute for Environmental Medicine [Düsseldorf, Germany] (IUF), Humboldt University Of Berlin, Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Coumoul, Xavier, Brinkmann, V, Romeo, M, Larigot, L, Hemmers, A, Tschage, L, Kleinjohann, J, Schiavi, A, Steinwachs, S, Esser, C, Menzel, R, Tagliabue, S, Bonati, L, Cox, F, Ale-Agha, N, Jakobs, P, Altschmied, J, Haendeler, J, Coumoul, X, and Ventura, N
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aryl hydrocarbon receptor ,curcumin ,oxidative stress ,Caenorhabditis elegans ,mice ,endothelial cells ,in vivo ,in vitro ,in silico ,Physiology ,Clinical Biochemistry ,Biochemistry ,Endothelial cell ,[SDV.BBM] Life Sciences [q-bio]/Biochemistry, Molecular Biology ,[SDV.BBM]Life Sciences [q-bio]/Biochemistry, Molecular Biology ,ddc:610 ,Molecular Biology ,Caenorhabditis elegan ,Cell Biology ,respiratory system ,respiratory tract diseases ,[SDV.TOX] Life Sciences [q-bio]/Toxicology ,[SDV.TOX]Life Sciences [q-bio]/Toxicology ,[SDV.SP.PHARMA] Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,[SDV.SP.PHARMA]Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,Oxidative stre ,610 Medizin und Gesundheit - Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor whose activity can be modulated by polyphenols such as curcumin. AhR and curcumin have evolutionarily conserved effects on aging. Here, we investigated whether and how the AhR mediates the anti-aging effects of curcumin across species. Using a combination of in vivo, in vitro, and in silico analyses, we demonstrated that curcumin has AhR-dependent or -independent effects in a context-specific manner. We found that in Caenorhabditis elegans, AhR mediates curcumin-induced lifespan extension, most likely through a ligand-independent inhibitory mechanism related to its antioxidant activity. Curcumin also showed AhR-independent anti-aging activities such as protection against aggregation-prone proteins and oxidative stress in C. elegans and promotion of the migratory capacity of human primary endothelial cells. These AhR-independent effects are largely mediated by the Nrf2/SKN-1 pathway.Graphical Abstract
- Published
- 2022
7. Caffeine Inhibits Oxidative Stress- and Low Dose Endotoxemia-Induced Senescence-Role of Thioredoxin-1.
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Merk D, Greulich J, Vierkant A, Cox F, Eckermann O, von Ameln F, Dyballa-Rukes N, Altschmied J, Ale-Agha N, Jakobs P, and Haendeler J
- Abstract
The maintenance of Thioredoxin-1 (Trx-1) levels, and thus of cellular redox homeostasis, is vital for endothelial cells (ECs) to prevent senescence induction. One hallmark of EC functionality, their migratory capacity, which depends on intact mitochondria, is reduced in senescence. Caffeine improves the migratory capacity and mitochondrial functionality of ECs. However, the impact of caffeine on EC senescence has never been investigated. Moreover, a high-fat diet, which can induce EC senescence, results in approximately 1 ng/mL lipopolysaccharide (LPS) in the blood. Therefore, we investigated if low dose endotoxemia induces EC senescence and concomitantly reduces Trx-1 levels, and if caffeine prevents or even reverses senescence. We show that caffeine precludes H
2 O2 -triggered senescence induction by maintaining endothelial NO synthase (eNOS) levels and preventing the elevation of p21. Notably, 1 ng/mL LPS also increases p21 levels and reduces eNOS and Trx-1 amounts. These effects are completely blocked by co-treatment with caffeine. This prevention of senescence induction is similarly accomplished by the permanent expression of mitochondrial p27, a downstream effector of caffeine. Most importantly, after senescence induction by LPS, a single bolus of caffeine inhibits the increase in p21. This treatment also blocks Trx-1 degradation, suggesting that the reversion of senescence is intimately associated with a normalized redox balance.- Published
- 2023
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8. Aryl Hydrocarbon Receptor-Dependent and -Independent Pathways Mediate Curcumin Anti-Aging Effects.
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Brinkmann V, Romeo M, Larigot L, Hemmers A, Tschage L, Kleinjohann J, Schiavi A, Steinwachs S, Esser C, Menzel R, Giani Tagliabue S, Bonati L, Cox F, Ale-Agha N, Jakobs P, Altschmied J, Haendeler J, Coumoul X, and Ventura N
- Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor whose activity can be modulated by polyphenols, such as curcumin. AhR and curcumin have evolutionarily conserved effects on aging. Here, we investigated whether and how the AhR mediates the anti-aging effects of curcumin across species. Using a combination of in vivo, in vitro, and in silico analyses, we demonstrated that curcumin has AhR-dependent or -independent effects in a context-specific manner. We found that in Caenorhabditis elegans , AhR mediates curcumin-induced lifespan extension, most likely through a ligand-independent inhibitory mechanism related to its antioxidant activity. Curcumin also showed AhR-independent anti-aging activities, such as protection against aggregation-prone proteins and oxidative stress in C. elegans and promotion of the migratory capacity of human primary endothelial cells. These AhR-independent effects are largely mediated by the Nrf2/SKN-1 pathway.
- Published
- 2022
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9. Protective Effects of Curcumin in Cardiovascular Diseases-Impact on Oxidative Stress and Mitochondria.
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Cox FF, Misiou A, Vierkant A, Ale-Agha N, Grandoch M, Haendeler J, and Altschmied J
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- Animals, Mitochondria metabolism, Obesity complications, Obesity drug therapy, Obesity metabolism, Oxidative Stress, Cardiovascular Diseases metabolism, Curcumin metabolism, Curcumin pharmacology, Curcumin therapeutic use, Diabetes Mellitus, Type 2 metabolism
- Abstract
Cardiovascular diseases (CVDs) contribute to a large part of worldwide mortality. Similarly, two of the major risk factors for these diseases, aging and obesity, are also global problems. Aging, the gradual decline of body functions, is non-modifiable. Obesity, a modifiable risk factor for CVDs, also predisposes to type 2 diabetes mellitus (T2DM). Moreover, it affects not only the vasculature and the heart but also specific fat depots, which themselves have a major impact on the development and progression of CVDs. Common denominators of aging, obesity, and T2DM include oxidative stress, mitochondrial dysfunction, metabolic abnormalities such as altered lipid profiles and glucose metabolism, and inflammation. Several plant substances such as curcumin, the major active compound in turmeric root, have been used for a long time in traditional medicine and for the treatment of CVDs. Newer mechanistic, animal, and human studies provide evidence that curcumin has pleiotropic effects and attenuates numerous parameters which contribute to an increased risk for CVDs in aging as well as in obesity. Thus, curcumin as a nutraceutical could hold promise in the prevention of CVDs, but more standardized clinical trials are required to fully unravel its potential.
- Published
- 2022
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10. Mitochondrial Telomerase Reverse Transcriptase Protects From Myocardial Ischemia/Reperfusion Injury by Improving Complex I Composition and Function.
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Ale-Agha N, Jakobs P, Goy C, Zurek M, Rosen J, Dyballa-Rukes N, Metzger S, Greulich J, von Ameln F, Eckermann O, Unfried K, Brack F, Grandoch M, Thielmann M, Kamler M, Gedik N, Kleinbongard P, Heinen A, Heusch G, Gödecke A, Altschmied J, and Haendeler J
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- Animals, Electron Transport Complex I genetics, Female, Humans, Male, Mice, Mice, Transgenic, Mitochondria, Heart genetics, Mitochondrial Proteins genetics, Myocardial Reperfusion Injury genetics, Telomerase genetics, Electron Transport Complex I metabolism, Mitochondria, Heart enzymology, Mitochondrial Proteins metabolism, Myocardial Reperfusion Injury enzymology, Telomerase metabolism
- Abstract
Background: The catalytic subunit of telomerase, telomerase reverse transcriptase (TERT), has protective functions in the cardiovascular system. TERT is not only present in the nucleus but also in mitochondria. However, it is unclear whether nuclear or mitochondrial TERT is responsible for the observed protection, and the appropriate tools are missing to dissect this., Methods: We generated new mouse models containing TERT exclusively in the mitochondria (mitoTERT mice) or the nucleus (nucTERT mice) to finally distinguish between the functions of nuclear and mitochondrial TERT. Outcome after ischemia/reperfusion, mitochondrial respiration in the heart, and cellular functions of cardiomyocytes, fibroblasts, and endothelial cells, as well, were determined., Results: All mice were phenotypically normal. Although respiration was reduced in cardiac mitochondria from TERT-deficient and nucTERT mice, it was increased in mitoTERT animals. The latter also had smaller infarcts than wild-type mice, whereas nucTERT animals had larger infarcts. The decrease in ejection fraction after 1, 2, and 4 weeks of reperfusion was attenuated in mitoTERT mice. Scar size was also reduced and vascularization increased. Mitochondrial TERT protected a cardiomyocyte cell line from apoptosis. Myofibroblast differentiation, which depends on complex I activity, was abrogated in TERT-deficient and nucTERT cardiac fibroblasts and completely restored in mitoTERT cells. In endothelial cells, mitochondrial TERT enhanced migratory capacity and activation of endothelial nitric oxide synthase. Mechanistically, mitochondrial TERT improved the ratio between complex I matrix arm and membrane subunits, explaining the enhanced complex I activity. In human right atrial appendages, TERT was localized in mitochondria and there increased by remote ischemic preconditioning. The telomerase activator TA-65 evoked a similar effect in endothelial cells, thereby increasing their migratory capacity, and enhanced myofibroblast differentiation., Conclusions: Mitochondrial, but not nuclear TERT, is critical for mitochondrial respiration and during ischemia/reperfusion injury. Mitochondrial TERT improves complex I subunit composition. TERT is present in human heart mitochondria, and remote ischemic preconditioning increases its level in those organelles. TA-65 has comparable effects ex vivo and improves the migratory capacity of endothelial cells and myofibroblast differentiation. We conclude that mitochondrial TERT is responsible for cardioprotection, and its increase could serve as a therapeutic strategy.
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- 2021
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11. Selenoprotein T Protects Endothelial Cells against Lipopolysaccharide-Induced Activation and Apoptosis.
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Merk D, Ptok J, Jakobs P, von Ameln F, Greulich J, Kluge P, Semperowitsch K, Eckermann O, Schaal H, Ale-Agha N, Altschmied J, and Haendeler J
- Abstract
Sepsis is an exaggerated immune response upon infection with lipopolysaccharide (LPS) as the main causative agent. LPS-induced activation and apoptosis of endothelial cells (EC) can lead to organ dysfunction and finally organ failure. We previously demonstrated that the first twenty amino acids of the Apurinic/Apyrimidinic Endodeoxyribonuclease 1 (APEX1) are sufficient to inhibit EC apoptosis. To identify genes whose regulation by LPS is affected by this N-terminal APEX1 peptide, EC were transduced with an expression vector for the APEX1 peptide or an empty control vector and treated with LPS. Following RNA deep sequencing, genes upregulated in LPS-treated EC expressing the APEX1 peptide were identified bioinformatically. Selected candidates were validated by semi-quantitative real time PCR, a promising one was Selenoprotein T (SELENOT). For functional analyses, an expression vector for SELENOT was generated. To study the effect of SELENOT expression on LPS-induced EC activation and apoptosis, the SELENOT vector was transfected in EC. Immunostaining showed that SELENOT was expressed and localized in the ER. EC transfected with the SELENOT plasmid showed no activation and reduced apoptosis induced by LPS. SELENOT as well as APEX1(1-20) can protect EC against activation and apoptosis and could provide new therapeutic approaches in the treatment of sepsis.
- Published
- 2021
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12. Endothelial hyaluronan synthase 3 aggravates acute colitis in an experimental model of inflammatory bowel disease.
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Hundhausen C, Schneckmann R, Ostendorf Y, Rimpler J, von Glinski A, Kohlmorgen C, Pasch N, Rolauer L, von Ameln F, Eckermann O, Altschmied J, Ale-Agha N, Haendeler J, Flögel U, Fischer JW, and Grandoch M
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- Animals, Disease Models, Animal, Endothelium, Humans, Hyaluronan Synthases genetics, Mice, Mice, Inbred C57BL, Models, Theoretical, Colitis chemically induced, Colitis genetics, Inflammatory Bowel Diseases genetics
- Abstract
The association between hyaluronan (HA) accumulation and increased inflammation in the colon suggests that HA is a potential therapeutic target in inflammatory bowel disease (IBD). However, whether patients with IBD would benefit from interference with HA synthesis is unknown. Here, we used pharmacological and genetic approaches to investigate the impact of systemic and partial blockade of HA synthesis in the Dextran Sodium Sulfate (DSS)-induced colitis model. To systemically inhibit HA production, we used 4-Methylumbelliferone (4-MU), whereas genetic approaches included the generation of mice with global or inducible cell-type specific deficiency in the Hyaluronan synthase 3 (Has3). We found that 4-MU treatment did not ameliorate but exacerbated disease severity characterized by increased body weight loss and enhanced colon tissue destruction compared to control mice without colitis. In contrast, global Has3 deficiency had a profound protective effect as reflected by a low colitis score and reduced infiltration of immune cells into the colon. To get further mechanistic insight into the proinflammatory role of HAS3, we deleted Has3 in a cell-type specific manner. Interestingly, while lack of Has3 expression in intestinal epithelial and smooth muscle cells had no effect or was rather proinflammatory, mice with Has3 deficiency in the endothelium were strongly protected against acute colitis. We conclude that endothelium-derived HAS3 plays a critical role in driving experimental colitis, warranting future studies on cell type-specific therapeutic interference with HA production in human IBD., Competing Interests: Conflict of Interest None declared., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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13. Extra-Nuclear Functions of the Transcription Factor Grainyhead-Like 3 in the Endothelium-Interaction with Endothelial Nitric Oxide Synthase.
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Jander K, Greulich J, Gonnissen S, Ale-Agha N, Goy C, Jakobs P, Farrokh S, Marziano C, Sonkusare SK, Haendeler J, and Altschmied J
- Abstract
We previously demonstrated that the transcription factor Grainyhead-like 3 (GRHL3) has essential functions in endothelial cells by inhibiting apoptosis and promoting migration as well as activation of endothelial nitric oxide synthase (eNOS). We now show that a large portion of the protein is localized to myo-endothelial projections of murine arteries suggesting extra-nuclear functions. Therefore, we generated various deletion mutants to identify the nuclear localization signal (NLS) of GRHL3 and assessed potential extra-nuclear functions. Several large-scale deletion mutants were incapable of activating a GRHL3-dependent reporter construct, which could either be due to deficiencies in transcriptional activation or to impaired nuclear import. One of these mutants encompassed a predicted bipartite NLS whose deletion led to the retention of GRHL3 outside the nucleus. Interestingly, this mutant retained functions of the full-length protein as it could still inhibit pathways inducing endothelial cell apoptosis. As apoptosis protection by GRHL3 depends on NO-production, we examined whether GRHL3 could interact with eNOS and showed a direct interaction, which was enhanced with the extra-nuclear GRHL3 variant. The observation that endogenous GRHL3 also interacts with eNOS in intact murine arteries corroborated these findings and substantiated the notion that GRHL3 has important extra-nuclear functions in the endothelium.
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- 2021
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14. Non-canonical functions of Telomerase Reverse Transcriptase - Impact on redox homeostasis.
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Rosen J, Jakobs P, Ale-Agha N, Altschmied J, and Haendeler J
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- Homeostasis, Mitochondria genetics, Mitochondria metabolism, Oxidation-Reduction, Telomere genetics, Telomere metabolism, Telomerase genetics, Telomerase metabolism
- Abstract
Telomerase consists of the catalytic subunit Telomerase Reverse Transcriptase (TERT) and the Telomerase RNA Component. Its canonical function is the prevention of telomere erosion. Over the last years it became evident that TERT is also present in tissues with low replicative potential. Important non-canonical functions of TERT are protection against apoptosis and maintenance of the cellular redox homeostasis in cancer as well as in somatic tissues. Intriguingly, TERT and reactive oxygen species (ROS) are interdependent on each other, with TERT being regulated by changes in the redox balance and itself controlling ROS levels in the cytosol and in the mitochondria. The latter is achieved because TERT is present in the mitochondria, where it protects mitochondrial DNA and maintains levels of anti-oxidative enzymes. Since numerous diseases are associated with oxidative stress, increasing the mitochondrial TERT level could be of therapeutic value., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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15. The Aryl Hydrocarbon Receptor (AhR) in the Aging Process: Another Puzzling Role for This Highly Conserved Transcription Factor.
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Brinkmann V, Ale-Agha N, Haendeler J, and Ventura N
- Abstract
Aging is the most important risk factor for the development of major life-threatening diseases such as cardiovascular disorders, cancer, and neurodegenerative disorders. The aging process is characterized by the accumulation of damage to intracellular macromolecules and it is concurrently shaped by genetic, environmental and nutritional factors. These factors influence the functionality of mitochondria, which play a central role in the aging process. Mitochondrial dysfunction is one of the hallmarks of aging and is associated with increased fluxes of ROS leading to damage of mitochondrial components, impaired metabolism of fatty acids, dysregulated glucose metabolism, and damage of adjacent organelles. Interestingly, many of the environmental (e.g., pollutants and other toxicants) and nutritional (e.g., flavonoids, carotenoids) factors influencing aging and mitochondrial function also directly or indirectly affect the activity of a highly conserved transcription factor, the Aryl hydrocarbon Receptor (AhR). Therefore, it is not surprising that many studies have already indicated a role of this versatile transcription factor in the aging process. We also recently found that the AhR promotes aging phenotypes across species. In this manuscript, we systematically review the existing literature on the contradictory studies indicating either pro- or anti-aging effects of the AhR and try to reconcile the seemingly conflicting data considering a possible dependency on the animal model, tissue, as well as level of AhR expression and activation. Moreover, given the crucial role of mitochondria in the aging process, we summarize the growing body of evidence pointing toward the influence of AhR on mitochondria, which can be of potential relevance for aging., (Copyright © 2020 Brinkmann, Ale-Agha, Haendeler and Ventura.)
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- 2020
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16. High Concentration of Low-Density Lipoprotein Results in Disturbances in Mitochondrial Transcription and Functionality in Endothelial Cells.
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Gonnissen S, Ptok J, Goy C, Jander K, Jakobs P, Eckermann O, Kaisers W, von Ameln F, Timm J, Ale-Agha N, Haendeler J, Schaal H, and Altschmied J
- Subjects
- Humans, Transcription, Genetic, Endothelial Cells metabolism, Lipoproteins, LDL metabolism, Mitochondria metabolism
- Abstract
Concentrations of low-density lipoprotein (LDL) above 0.8 mg/ml have been associated with increased risk for cardiovascular diseases and impaired endothelial functionality. Here, we demonstrate that high concentrations of LDL (1 mg/ml) decreased NOS3 protein and RNA levels in primary human endothelial cells. In addition, RNA sequencing data, in particular splice site usage analysis, showed a shift in NOS3 exon-exon junction reads towards those specifically assigned to nonfunctional transcript isoforms further diminishing the functional NOS3 levels. The reduction in NOS3 was accompanied by decreased migratory capacity, which depends on intact mitochondria and ATP formation. In line with these findings, we also observed a reduced ATP content. While mitochondrial mass was unaffected by high LDL, we found an increase in mitochondrial DNA copy number and mitochondrial RNA transcripts but decreased expression of nuclear genes coding for respiratory chain proteins. Therefore, high LDL treatment most likely results in an imbalance between respiratory chain complex proteins encoded in the mitochondria and in the nucleus resulting in impaired respiratory chain function explaining the reduction in ATP content. In conclusion, high LDL treatment leads to a decrease in active NOS3 and dysregulation of mitochondrial transcription, which is entailed by reduced ATP content and migratory capacity and thus, impairment of endothelial cell functionality.
- Published
- 2019
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17. Induction of a senescent like phenotype and loss of gap junctional intercellular communication by carbon nanoparticle exposure of lung epithelial cells.
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Spannbrucker T, Ale-Agha N, Goy C, Dyballa-Rukes N, Jakobs P, Jander K, Altschmied J, Unfried K, and Haendeler J
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- Animals, Cell Communication drug effects, Cell Communication physiology, Cell Proliferation drug effects, Cells, Cultured, Cellular Senescence physiology, Connexin 43 metabolism, Cyclin-Dependent Kinase Inhibitor p21 metabolism, Epithelial Cells cytology, Epithelial Cells drug effects, Epithelial Cells metabolism, Gap Junctions physiology, Nanoparticles, Particle Size, Pulmonary Alveoli cytology, Pulmonary Alveoli metabolism, Rats, Sirtuin 1 metabolism, Carbon pharmacology, Cellular Senescence drug effects, Gap Junctions drug effects, Pulmonary Alveoli drug effects
- Abstract
Inhalation of combustion-derived particles is associated with the development of age-related diseases like chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. In both diseases senescence of lung epithelial cells has been observed. Employing an in vitro system of repetitive exposure to pure carbon nanoparticles we asked whether this kind of particles are able to induce a senescent like phenotype, which might be accompanied by a loss of functionality at the level of gap junctional intercellular communication. Non-cytotoxic doses of carbon nanoparticles but not of bigger carbon particles led to an irreversible reduction of the proliferative capacity accompanied by the accumulation of the cell cycle blocking proteins p21 and p16 as well as a loss of both redox sensitive histone deacetylase SIRT1 and connexin-43. Gap junction intercellular communication detected by microinjection of fluorescent lucifer yellow was dramatically decreased after exposure. This loss of functionality was associated with a reduction of Connexin 43 at the plasma membrane. As the experimental system was chosen to study the effects of pure carbon nanoparticles in the absence of inflammatory cells, the data indicate that cumulative long-term exposure of the lung epithelium to low doses of combustion-derived nanoparticles might contribute to epithelial senescence and age-associated diseases of the airways., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2019
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18. CDKN1B/p27 is localized in mitochondria and improves respiration-dependent processes in the cardiovascular system-New mode of action for caffeine.
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Ale-Agha N, Goy C, Jakobs P, Spyridopoulos I, Gonnissen S, Dyballa-Rukes N, Aufenvenne K, von Ameln F, Zurek M, Spannbrucker T, Eckermann O, Jakob S, Gorressen S, Abrams M, Grandoch M, Fischer JW, Köhrer K, Deenen R, Unfried K, Altschmied J, and Haendeler J
- Subjects
- Adenosine Triphosphate metabolism, Animals, Apoptosis physiology, Cell Differentiation physiology, Cell Line, Cell Movement physiology, Cyclin-Dependent Kinase Inhibitor p27 genetics, Endothelial Cells physiology, HEK293 Cells, Humans, Membrane Potential, Mitochondrial physiology, Mice, Mice, Inbred C57BL, Mice, Knockout, Myocytes, Cardiac cytology, Protein Transport physiology, Caffeine pharmacology, Cardiotonic Agents pharmacology, Cyclin-Dependent Kinase Inhibitor p27 metabolism, Mitochondria metabolism, Myocardial Infarction pathology, Myocytes, Cardiac physiology
- Abstract
We show that the cyclin-dependent kinase inhibitor 1B (CDKN1B)/p27, previously known as a cell cycle inhibitor, is also localized within mitochondria. The migratory capacity of endothelial cells, which need intact mitochondria, is completely dependent on mitochondrial p27. Mitochondrial p27 improves mitochondrial membrane potential, increases adenosine triphosphate (ATP) content, and is required for the promigratory effect of caffeine. Domain mapping of p27 revealed that the N-terminus and C-terminus are required for those improvements. Further analysis of those regions revealed that the translocation of p27 into the mitochondria and its promigratory activity depend on serine 10 and threonine 187. In addition, mitochondrial p27 protects cardiomyocytes against apoptosis. Moreover, mitochondrial p27 is necessary and sufficient for cardiac myofibroblast differentiation. In addition, p27 deficiency and aging decrease respiration in heart mitochondria. Caffeine does not increase respiration in p27-deficient animals, whereas aged mice display improvement after 10 days of caffeine in drinking water. Moreover, caffeine induces transcriptome changes in a p27-dependent manner, affecting mostly genes relevant for mitochondrial processes. Caffeine also reduces infarct size after myocardial infarction in prediabetic mice and increases mitochondrial p27. Our data characterize mitochondrial p27 as a common denominator that improves mitochondria-dependent processes and define an increase in mitochondrial p27 as a new mode of action of caffeine., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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19. Non-Canonical Activation of the Epidermal Growth Factor Receptor by Carbon Nanoparticles.
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Stöckmann D, Spannbrucker T, Ale-Agha N, Jakobs P, Goy C, Dyballa-Rukes N, Hornstein T, Kümper A, Kraegeloh A, Haendeler J, and Unfried K
- Abstract
The epidermal growth factor receptor (EGFR) is an abundant membrane protein, which is essential for regulating many cellular processes including cell proliferation. In our earlier studies, we observed an activation of the EGFR and subsequent signaling events after the exposure of epithelial cells to carbon nanoparticles. In the current study, we describe molecular mechanisms that allow for discriminating carbon nanoparticle-specific from ligand-dependent receptor activation. Caveolin-1 is a key player that co-localizes with the EGFR upon receptor activation by carbon nanoparticles. This specific process mediated by nanoparticle-induced reactive oxygen species and the accumulation of ceramides in the plasma membrane is not triggered when cells are exposed to non-nano carbon particles or the physiological ligand EGF. The role of caveolae formation was demonstrated by the induction of higher order structures of caveolin-1 and by the inhibition of caveolae formation. Using an in vivo model with genetically modified mice lacking caveolin-1, it was possible to demonstrate that carbon nanoparticles in vivo trigger EGFR downstream signaling cascades via caveolin-1. The identified molecular mechanisms are, therefore, of toxicological relevance for inhaled nanoparticles. However, nanoparticles that are intentionally applied to humans might cause side effects depending on this phenomenon.
- Published
- 2018
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20. The Anti-Apoptotic Properties of APEX1 in the Endothelium Require the First 20 Amino Acids and Converge on Thioredoxin-1.
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Dyballa-Rukes N, Jakobs P, Eckers A, Ale-Agha N, Serbulea V, Aufenvenne K, Zschauer TC, Rabanter LL, Jakob S, von Ameln F, Eckermann O, Leitinger N, Goy C, Altschmied J, and Haendeler J
- Subjects
- Amino Acids genetics, Amino Acids metabolism, Blood Vessels metabolism, Blood Vessels pathology, Carotid Arteries metabolism, Carotid Arteries pathology, Caspase 3 genetics, Caspase 3 metabolism, Cathepsin D genetics, Cell Proliferation genetics, DNA-(Apurinic or Apyrimidinic Site) Lyase biosynthesis, Endothelial Cells metabolism, Gene Expression Regulation, Graft Occlusion, Vascular pathology, Humans, Myocytes, Smooth Muscle metabolism, Myocytes, Smooth Muscle pathology, Oxidative Stress genetics, Thioredoxins genetics, Apoptosis genetics, DNA-(Apurinic or Apyrimidinic Site) Lyase genetics, Graft Occlusion, Vascular genetics, Thioredoxins biosynthesis
- Abstract
The APEX nuclease (multifunctional DNA repair enzyme) 1 (APEX1) has a disordered N-terminus, a redox, and a DNA repair domain. APEX1 has anti-apoptotic properties, which have been linked to both domains depending on cell type and experimental conditions., Aims: As protection against apoptosis is a hallmark of vessel integrity, we wanted to elucidate whether APEX1 acts anti-apoptotic in primary human endothelial cells and, if so, what the underlying mechanisms are., Results: APEX1 inhibits apoptosis in endothelial cells by reducing Cathepsin D (CatD) cleavage, potentially by binding to the unprocessed form. Diminished CatD activation results in increased Thioredoxin-1 protein levels leading to reduced Caspase 3 activation. Consequently, apoptosis rates are decreased. This depends on the first twenty amino acids in APEX1, because APEX1 (21-318) induces CatD activity, decreases Thioredoxin-1 protein levels, and, thus, increases Caspase 3 activity and apoptosis. Along the same lines, APEX1 (1-20) inhibits Caspase 3 cleavage and apoptosis. Furthermore, re-expression of Thioredoxin-1 via lentiviral transduction rescues endothelial cells from APEX1 (21-318)-induced apoptosis. In an in vivo model of restenosis, which is characterized by oxidative stress, endothelial activation, and smooth muscle cell proliferation, Thioredoxin-1 protein levels are reduced in the endothelium of the carotids., Innovation: APEX1 acts anti-apoptotic in endothelial cells. This anti-apoptotic effect depends on the first 20 amino acids of APEX1., Conclusion: As proper function of the endothelium during life span is a hallmark for individual health span, a detailed characterization of the functions of the APEX1N-terminus is required to understand all its cellular properties. Antioxid. Redox Signal. 26, 616-629.
- Published
- 2017
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21. Role of Telomerase in the Cardiovascular System.
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Zurek M, Altschmied J, Kohlgrüber S, Ale-Agha N, and Haendeler J
- Abstract
Aging is one major risk factor for the incidence of cardiovascular diseases and the development of atherosclerosis. One important enzyme known to be involved in aging processes is Telomerase Reverse Transcriptase (TERT). After the discovery of the enzyme in humans, TERT had initially only been attributed to germ line cells, stem cells and cancer cells. However, over the last few years it has become clear that TERT is also active in cells of the cardiovascular system including cardiac myocytes, endothelial cells, smooth muscle cells and fibroblasts. Interference with the activity of this enzyme greatly contributes to cardiovascular diseases. This review will summarize the findings on the role of TERT in cardiovascular cells. Moreover, recent findings concerning TERT in different mouse models with respect to cardiovascular diseases will be described. Finally, the extranuclear functions of TERT will be covered within this review.
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- 2016
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22. The aryl hydrocarbon receptor promotes aging phenotypes across species.
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Eckers A, Jakob S, Heiss C, Haarmann-Stemmann T, Goy C, Brinkmann V, Cortese-Krott MM, Sansone R, Esser C, Ale-Agha N, Altschmied J, Ventura N, and Haendeler J
- Subjects
- Adult, Age Factors, Aged, Animals, Apoptosis, Caenorhabditis elegans genetics, Caenorhabditis elegans metabolism, Cell Line, Cell Movement, Cell Proliferation, Endothelial Cells metabolism, Gene Expression, Humans, Longevity genetics, Mice, Mice, Knockout, Middle Aged, Nitric Oxide metabolism, Nitric Oxide Synthase Type III metabolism, Phosphorylation, Pulse Wave Analysis, Quantitative Trait, Heritable, Receptors, Aryl Hydrocarbon agonists, Young Adult, Aging genetics, Aging metabolism, Phenotype, Receptors, Aryl Hydrocarbon genetics, Receptors, Aryl Hydrocarbon metabolism
- Abstract
The ubiquitously expressed aryl hydrocarbon receptor (AhR) induces drug metabolizing enzymes as well as regulators of cell growth, differentiation and apoptosis. Certain AhR ligands promote atherosclerosis, an age-associated vascular disease. Therefore, we investigated the role of AhR in vascular functionality and aging. We report a lower pulse wave velocity in young and old AhR-deficient mice, indicative of enhanced vessel elasticity. Moreover, endothelial nitric oxide synthase (eNOS) showed increased activity in the aortas of these animals, which was reflected in increased NO production. Ex vivo, AhR activation reduced the migratory capacity of primary human endothelial cells. AhR overexpression as well as treatment with a receptor ligand, impaired eNOS activation and reduced S-NO content. All three are signs of endothelial dysfunction. Furthermore, AhR expression in blood cells of healthy human volunteers positively correlated with vessel stiffness. In the aging model Caenorhabditis elegans, AhR-deficiency resulted in increased mean life span, motility, pharynx pumping and heat shock resistance, suggesting healthier aging. Thus, AhR seems to have a negative impact on vascular and organismal aging. Finally, our data from human subjects suggest that AhR expression levels could serve as an additional, new predictor of vessel aging.
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- 2016
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23. Signalling-dependent adverse health effects of carbon nanoparticles are prevented by the compatible solute mannosylglycerate (firoin) in vitro and in vivo.
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Autengruber A, Sydlik U, Kroker M, Hornstein T, Ale-Agha N, Stöckmann D, Bilstein A, Albrecht C, Paunel-Görgülü A, Suschek CV, Krutmann J, and Unfried K
- Subjects
- Animals, Apoptosis drug effects, Cell Line, Enzyme Activation, Humans, In Vitro Techniques, Lung drug effects, Lung enzymology, Male, Mannose pharmacology, Mitogen-Activated Protein Kinases metabolism, Neutrophils cytology, Neutrophils drug effects, Carbon chemistry, Glyceric Acids pharmacology, Mannose analogs & derivatives, Nanoparticles adverse effects, Signal Transduction
- Abstract
The inhalation of combustion-derived nanoparticles leads to adverse health effects in the airways. In this context the induction of membrane-coupled signalling is considered as causative for changes in tissue homeostasis and pro-inflammatory reactions. The identification of these molecular cell reactions allowed to seek for strategies which interfere with these adverse effects. In the current study, we investigated the structurally different compatible solutes mannosylglycerate (firoin) from thermophilic bacteria and ectoine from halophilic bacteria for their capability to reduce signalling pathways triggered by carbon nanoparticles in target cells in the lung. The pre-treatment of lung epithelial cells with both substances decreased the particle-specific activation of mitogen-activated protein kinases and also the endpoints proliferation and apoptosis. Firoin applied into the lungs of animals, like ectoine, led to a significant reduction of the neutrophilic lung inflammation induced by particle exposure. The pro-inflammatory effect of carbon nanoparticles on human neutrophil granulocytes ex vivo was significantly reduced by both substances via the reduction of the anti-apoptotic membrane-dependent signalling. The data of this study together with earlier studies demonstrate that two structurally non-related compatible solutes are able to prevent pathogenic reactions of the airways to carbon nanoparticles by interfering with signalling events. The findings highlight the preventive or therapeutic potential of compatible solutes for adverse health effects caused by particle exposure of the airways.
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- 2014
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24. Cellular functions of the dual-targeted catalytic subunit of telomerase, telomerase reverse transcriptase--potential role in senescence and aging.
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Ale-Agha N, Dyballa-Rukes N, Jakob S, Altschmied J, and Haendeler J
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- Active Transport, Cell Nucleus, Age Factors, Aging genetics, Animals, Catalytic Domain, Humans, Phosphorylation, Signal Transduction, Telomerase genetics, Aging metabolism, Cellular Senescence, Mitochondria enzymology, Telomerase metabolism, Telomere metabolism
- Abstract
Over the last 40 years it has become clear that telomeres, the end of the chromosomes, and the enzyme telomerase reverse transcriptase (TERT), which is required to counteract their shortening, play a pivotal role in senescence and aging. However, over the last years several studies demonstrated that TERT belongs to the group of dual-targeted proteins. It contains a bipartite nuclear localization signal as well as a mitochondrial targeting sequence and, under physiological conditions, is found in both organelles in several cell types including terminally differentiated, post-mitotic cells. The canonical function of TERT is to prevent telomere erosion and thereby the development of replicative senescence and genetic instability. Besides telomere extension, TERT exhibits other non-telomeric activities such as cell cycle regulation, modulation of cellular signaling and gene expression, augmentation of proliferative lifespan as well as DNA damage responses. Mitochondrial TERT is able to reduce reactive oxygen species, mitochondrial DNA damage and apoptosis. Because of the localization of TERT in the nucleus and in the mitochondria, it must have different functions in the two organelles as mitochondrial DNA does not contain telomeric structures. However, the organelle-specific functions are not completely understood. Strikingly, the regulation by phosphorylation of TERT seems to reveal multiple parallels. This review will summarize the current knowledge about the cellular functions and post-translational regulation of the dual-targeted protein TERT., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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25. The imbalanced redox status in senescent endothelial cells is due to dysregulated Thioredoxin-1 and NADPH oxidase 4.
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Goy C, Czypiorski P, Altschmied J, Jakob S, Rabanter LL, Brewer AC, Ale-Agha N, Dyballa-Rukes N, Shah AM, and Haendeler J
- Subjects
- Animals, Cathepsin D metabolism, Cells, Cultured, Endothelial Cells drug effects, Gene Expression Regulation, Humans, Hydrogen Peroxide pharmacology, Mice, Inbred C57BL, Mice, Transgenic, NADPH Oxidase 4, NADPH Oxidases genetics, Oxidants pharmacology, Oxidation-Reduction, Signal Transduction, Thioredoxins genetics, Transfection, Cellular Senescence drug effects, Endothelial Cells enzymology, NADPH Oxidases metabolism, Oxidative Stress drug effects, Thioredoxins metabolism
- Abstract
Environmental stressors as well as genetic modifications are known to enhance oxidative stress and aging processes. Mitochondrial and nuclear dysfunctions contribute to the onset of aging. One of the most important redox regulators in primary human endothelial cells is Thioredoxin-1 (Trx-1), a 12 kD protein with additional anti-apoptotic properties. Cellular generators of reactive oxygen species are NADPH oxidases (NOXs), of which NOX4 shows highest expression levels in endothelial cells. Therefore, the aim of the study was to investigate how Trx-1 and NOX4 are regulated during stress-induced premature senescence in endothelial cells. We treated primary human endothelial cells for two weeks with H2O2 to generate stress-induced premature senescence in these cells. In this model senescence-associated β-Galactosidase and nuclear p21 as senescence markers are increased. Moreover, total and mitochondrial reactive oxygen species formation is enhanced. An imbalanced redox homeostasis is detected by elevated NOX4 and decreased Trx-1 levels. This can be rescued by lentiviral expression of Trx-1. Moreover, the lysosomal protease Cathepsin D is over-activated, which results in reduced Trx-1 protein levels. Inhibition of "over-active" Cathepsin D by the specific, cell-permeable inhibitor pepstatin A abolishes the increase in nuclear p21 protein, ROS formation and degradation of Trx-1 protein, thus leading to blockade of stress-induced premature senescence by stabilizing the cellular redox homeostasis. Aortic Trx-1 levels are decreased and Cathepsin D activity is increased in NOX4 transgenic mice exclusively expressing NOX4 in the endothelium when compared to their wildtype littermates. Thus, loss of Trx-1 and upregulation of NOX4 importantly contribute to the imbalance in the redox-status of senescent endothelial cells ex vivo and in vivo., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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26. Hydrogen peroxide sensing and signaling by protein kinases in the cardiovascular system.
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Burgoyne JR, Oka S, Ale-Agha N, and Eaton P
- Subjects
- Animals, Cysteine metabolism, Homeostasis, Humans, Hydrogen Peroxide pharmacology, Intracellular Signaling Peptides and Proteins physiology, Methionine metabolism, Models, Cardiovascular, Oxidation-Reduction, Oxidoreductases metabolism, Phosphorylation, Protein Processing, Post-Translational, Second Messenger Systems physiology, Sulfhydryl Compounds metabolism, Superoxide Dismutase metabolism, Superoxide Dismutase-1, Superoxides metabolism, Calcium-Calmodulin-Dependent Protein Kinase Type 2 physiology, Cardiovascular System metabolism, Cyclic AMP-Dependent Protein Kinases physiology, Cyclic GMP-Dependent Protein Kinases physiology, Hydrogen Peroxide metabolism, Signal Transduction physiology
- Abstract
Significance: Oxidants were once principally considered perpetrators of injury and disease. However, this has become an antiquated view, with cumulative evidence showing that the oxidant hydrogen peroxide serves as a signaling molecule. Hydrogen peroxide carries vital information about the redox state of the cell and is crucial for homeostatic regulation during health and adaptation to stress., Recent Advances: In this review, we examine the contemporary concepts for how hydrogen peroxide is sensed and transduced into a biological response by introducing post-translational oxidative modifications on select proteins. Oxidant sensing and signaling by kinases are of particular importance as they integrate oxidant signals into phospho-regulated pathways. We focus on CAMKII, PKA, and PKG, kinases whose redox regulation has notable impact on cardiovascular function., Critical Issues: In addition, we examine the mechanism for regulating intracellular hydrogen peroxide, considering the net concentrations that may accumulate. The effects of endogenously generated oxidants are often modeled by applying exogenous hydrogen peroxide to cells or tissues. Here we consider whether model systems exposed to exogenous hydrogen peroxide have relevance to systems where the oxidant is generated endogenously, and if so, what concentration can be justified in terms of relevance to health and disease., Future Directions: Improving our understanding of hydrogen peroxide signaling and the sensor proteins that it can modify will help us develop new strategies to regulate intracellular signaling to prevent disease.
- Published
- 2013
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27. Unhealthy diet and ultrafine carbon black particles induce senescence and disease associated phenotypic changes.
- Author
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Büchner N, Ale-Agha N, Jakob S, Sydlik U, Kunze K, Unfried K, Altschmied J, and Haendeler J
- Subjects
- Air Pollutants pharmacology, Air Pollutants toxicity, Animals, Aorta, Abdominal enzymology, Cell Proliferation drug effects, Cellular Senescence physiology, Cholesterol, LDL pharmacology, Culture Media pharmacology, Endothelial Cells drug effects, Endothelial Cells metabolism, Female, Fructose pharmacology, Glucose pharmacology, Humans, Mice, Mice, Inbred BALB C, Myocytes, Cardiac drug effects, Myocytes, Cardiac metabolism, Myocytes, Smooth Muscle drug effects, Myocytes, Smooth Muscle metabolism, Nitric Oxide biosynthesis, Nitric Oxide Synthase biosynthesis, Nitric Oxide Synthase Type III biosynthesis, Particle Size, Phenotype, Reactive Oxygen Species metabolism, Soot toxicity, Telomerase biosynthesis, src-Family Kinases biosynthesis, Cellular Senescence drug effects, Diet, Soot pharmacology
- Abstract
Diet and pollution are environmental factors known to compromise "healthy aging" of the cardiovascular and respiratory systems. The molecular consequences of this permanent burden in these cells are still unknown. Therefore, this study investigates the impact of unhealthy diet on aging-related signaling pathways of human, primary cardiovascular cells and of airborne particles on lung epithelial and human endothelial cells. Nutrition health reports have shown that the diet in industrialized countries contains more than 100mg/dl low density lipoprotein (LDL) and a high fraction of added sugars, especially fructose. Several studies demonstrated that ultrafine particles can enter the circulation and thus may interact with endothelial cells directly. Both, dietary compounds and pollution derived particles, have been shown to increase the risk for cardiovascular diseases. To simulate an unhealthy diet, we supplemented cell culture media of human primary endothelial cells, smooth muscle cells and cardiomyocytes with LDL and replaced 1/3 of glucose with fructose. We observed hypertrophy in cardiomyocytes, enhanced proliferation in smooth muscle cells and increased senescence, loss of endothelial nitric oxide synthase and increased nuclear FoxO3A in endothelial cells. With respect to pollution we have used ultrafine carbon black particles (ufCB), one of the major constituents of industrial and exhaust emissions, in concentrations our lungs and vessels are constantly exposed to. These concentrations of ufCB increased reactive oxygen species in lung epithelial and vascular endothelial cells and reduced the S-NO content, a marker for NO-bioavailability, in endothelial cells. NO increases activation of Telomerase Reverse Transcriptase (TERT), an enzyme essential for telomere maintenance. TERT is required for proper endothelial cell function and is inactivated by Src kinase under conditions of oxidative stress. ufCB significantly increased Src kinase activation and reduced Telomerase activity in endothelial and lung epithelial cells. As a consequence, ufCB increased senescence of endothelial cells. To investigate whether ufCB show also effects in vivo, we instilled ufCB in concentrations not inducing inflammation into mice. Indeed, eNOS expression was reduced in the abdominal aorta of animals treated with ufCB. Thus, a combination of fructose and LDL in the diet and ufCB, as a major constituent of air pollution, seem to accelerate respiratory and cardiovascular cellular changes, which may compromise "healthy aging" and can lead to cardiovascular and pulmonary diseases., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2013
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28. Validity and reliability of skin markers for measurement of intersegmental mobility at L2-3 and L3-4 during lateral bending in healthy individuals: a fluoroscopy study.
- Author
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Hashemirad F, Hatef B, Jaberzadeh S, and Ale Agha N
- Subjects
- Adult, Biomechanical Phenomena, Body Height, Body Weight, Fluoroscopy methods, Humans, Posture, Reference Values, Reproducibility of Results, Sampling Studies, Sensitivity and Specificity, Skin, Spinal Curvatures, Young Adult, Arthrometry, Articular methods, Fiducial Markers, Lumbar Vertebrae diagnostic imaging, Lumbar Vertebrae physiology, Range of Motion, Articular physiology
- Abstract
It is clinically important to assess kinematic parameters of lumbar spine movement to increase our understanding of lumbar mobility impairments in patients with low back pain. This is the first step for restoration of motor function. The use of non-invasive surface markers has currently attracted the interests of many researchers but scientific utilization of this technique for clinical research requires validity and reliability studies. The aim of the present study was to examine whether skin markers can be used to measure lumbar motions during lateral bending. Twelve healthy individuals were lying in prone position on the video fluoroscopy table and skin markers were attached over their spinous processes. Fluoroscopy images were taken in two positions of neutral and right lateral bending (RLB). The correlation of the L2-3 and L3-4 angles and lumbar curvature between markers and vertebrae measurements in the neutral and RLB positions was determined by Pearson Correlation Coefficient. The Intraclass correlation coefficient (ICC) was used to measure inter-examiner reliability of measurement in five participants. The results showed high reliability (ranging from 0.94 to 0.99) for angular measurements at L2-3 and L3-4 and lumbar curvature and also significant correlation between angular measurement derived from markers and vertebrae at L2-3 (r = 0.7, p = 0.015), L3-4 and lumbar curvature (r = 0.91 p = 0.001). The results showed that motions of skin markers follow the motions of the assigned underlying lumbar vertebrae. Therefore, skin markers can be confidently used for estimation of lumbar movements during lateral bending., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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29. Survey of microfungi in the Landschaftspark Duisburg-Nord (Germany).
- Author
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Jensen M, Nerat N, and Ale-Agha N
- Subjects
- Germany, Air Microbiology, Environmental Monitoring, Fungi classification, Fungi isolation & purification, Plants microbiology
- Abstract
During an excursion in the Landschaftspark Duisburg-Nord in 2009 and 2010 we were able to collect and identify more than 100 specimens of microfungi on different parts of cultivated and wild plant species. We found parasitic and saprophytic microfungi on trees, bushes and herbaceous plants. Some of them have been observed only rarely until now. Most of the collected microfungi species belong to the classes of Ascomycetes, Basidiomycetes and Deuteromycetes - for example Leptosphaeria modesta (Desm.) Rabenh. on Knautia cf. arvensis (L.) Coult., Ramularia urticae Ces. on Urtica dioica L., Stigmina glomerulosa (Sacc.) S. Hughes on Juniperus communis L., Pseudomassaria corni (Sowerby) Arx on Cornus alba L., Mollisia discolor (Mont.) W. Phillips on Cornus alba L., Botryosphaeria quercuum (Schwein.) Sacc. on Quercus robur L., Peronospora cytisi Rostr. on Laburnum anagyroides Med., Microsphaera guarinonii Briosi and Cavara on Laburnum anagyroides Med., Brachysporium dingleyae S. Hughes on Fraxinus angustifolia Vahl and Rhododendron spec., Mamiania fimbriata (Pers.) Ces. and De Not. on Carpinus betulus L., Atopospora betulina (Fr.) Petr. on Betula pendula Roth, Septoria robiniae (Lib.) Desm. (=Phloeospora robiniae (Lib.) Höhn.) on Robinia pseudoacacia L., Chalara hughesii Nag Raj and W.B. Kendr. on Quercus robur L.. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige and N. Ale-Agha.
- Published
- 2011
30. Loss of gap junctional intercellular communication in rat lung epithelial cells exposed to carbon or silica-based nanoparticles.
- Author
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Ale-Agha N, Albrecht C, and Klotz LO
- Subjects
- Animals, Cells, Cultured, Connexin 43 metabolism, Connexins metabolism, Epithelial Cells metabolism, Epithelial Cells ultrastructure, ErbB Receptors metabolism, Isoquinolines, Lung cytology, Lung metabolism, Nanoparticles toxicity, Phosphorylation, Rats, beta Catenin metabolism, Carbon toxicity, Cell Communication drug effects, Gap Junctions drug effects, Gap Junctions metabolism, Silicon Dioxide toxicity
- Abstract
The aim of this study was to investigate whether fine and ultrafine carbon black (fC and ufC), and fine and ultrafine silica (fS, ufS) particles affect gap junctional intercellular communication (GJIC) in rat lung epithelial cells. Exposure of cells to subcytotoxic doses of ufC, fS and ufS resulted in a 63%, 59% and 77% reduction of GJIC, respectively, as determined in a dye transfer assay. In contrast to ufC, fC did not significantly alter GJIC. Changes in subcellular localization of the major gap junction protein in RLE cells, connexin-43 (Cx43), and of β-catenin were observed in cells exposed to ufC, fS or ufS. The loss of GJIC was counteracted by N-acetyl cysteine and was largely prevented by specific inhibitors of epidermal growth factor receptor-dependent signaling, pointing to the crucial role of two known major mediators of nanoparticle action, namely reactive oxygen species and membrane-receptor signaling, in particle-induced modulation of GJIC.
- Published
- 2010
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31. Role of HuR and p38MAPK in ultraviolet B-induced post-transcriptional regulation of COX-2 expression in the human keratinocyte cell line HaCaT.
- Author
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Fernau NS, Fugmann D, Leyendecker M, Reimann K, Grether-Beck S, Galban S, Ale-Agha N, Krutmann J, and Klotz LO
- Subjects
- Antigens, Surface genetics, Blotting, Western, Cell Line, Cell Survival radiation effects, Cyclooxygenase 2 metabolism, Cytoplasm metabolism, Cytoplasm radiation effects, Dinoprostone metabolism, Dose-Response Relationship, Radiation, ELAV Proteins, ELAV-Like Protein 1, Gene Expression Regulation radiation effects, Gene Expression Regulation, Enzymologic radiation effects, Humans, Indoles pharmacology, Keratinocytes cytology, Keratinocytes metabolism, Maleimides pharmacology, Protein Kinase C antagonists & inhibitors, Protein Kinase C metabolism, RNA Interference, RNA Stability radiation effects, RNA-Binding Proteins genetics, Reverse Transcriptase Polymerase Chain Reaction, p38 Mitogen-Activated Protein Kinases genetics, Antigens, Surface metabolism, Cyclooxygenase 2 genetics, Keratinocytes radiation effects, RNA-Binding Proteins metabolism, Ultraviolet Rays, p38 Mitogen-Activated Protein Kinases metabolism
- Abstract
COX-2 (cyclooxygenase-2) is a pivotal player in inflammatory processes, and ultraviolet radiation is a known stimulus for COX-2 expression in skin cells. Here, an induction of COX-2 expression in HaCaT human keratinocytes was observed only upon exposure of cells to UVB (280-320 nm) but not to UVA radiation (320-400 nm), as demonstrated by reverse transcription-PCR and Western blotting. Prostaglandin E(2) levels were elevated in cell culture supernatants of HaCaT cells exposed to UVB. COX-2 mRNA stability was dramatically increased by UVB irradiation. Both the stabilization of COX-2 mRNA and the enhancement of COX-2 steady-state mRNA and protein levels caused by UVB were prevented both by inhibition and small interfering RNA-induced depletion of p38(MAPK), a kinase strongly activated upon exposure to UVB, suggesting p38(MAPK)-dependent mRNA stabilization as a mechanism of UVB-induced COX-2 expression. A dramatic decrease in COX-2 expression induced by UVB was elicited by small interfering RNA-based depletion of a stress-responsive mRNA stabilizing protein regulated by p38(MAPK), i.e. HuR; UVB-induced elevation of COX-2 mRNA and protein levels coincided with an accumulation of HuR in the cytoplasm and was attenuated in cells depleted of HuR. Moreover, UVB-induced generation of prostaglandin E(2) by HaCaT cells was blunted by HuR depletion, suggesting that stress kinases (such as p38(MAPK)) as well as HuR are excellent targets for approaches aiming at interfering with induction of COX-2 expression by UVB.
- Published
- 2010
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32. New remarkable records of microfungi from Sardinia (Italy).
- Author
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Jensen M, Nerat N, and Ale-Agha N
- Subjects
- Fungi classification, Fungi genetics, Fungi growth & development, Italy, Spores, Fungal classification, Spores, Fungal genetics, Spores, Fungal growth & development, Spores, Fungal isolation & purification, Fungi isolation & purification, Plant Diseases microbiology, Plants microbiology
- Abstract
In June 2009 we organized a botanical student excursion to the eastern part of Sardinia, Italy. On this occasion we were able to collect and identify over 80 species of microfungi growing on higher plants. The collecting sites were spread over a large area, among them were La Caletta, Capo Comino, Monte Albo, Cala Gonone, Monte Maccione, San Teodoro, Capo Testa. The collected microfungi were parasitic or saprophytic; Basidiomycotina (Uredinales), Ascomycotina and Deuteromycotina (Hyphomycetes, Coelomycetes) were predominant. Examples are Pezicula corticola (Jörg.) NANNF. (new for Sardinia), on Pyrus communis. Puccinia chamaecyparissi TROTT. (new for Sardinia), on Santolina insularis. Sphaceloma oleae CICC. and GRANITI (new for Sardinia) and Phlyctema vagabunda DESM. (new for Sardinia), on Olea europaea and Arbutus unedo. Puccinia pseudosphaeria MONT. (new for Sardinia), on Sonchus oleraceus. Discula umbrinella (BERK. and BR.) SUTTON (new for Sardinia)(D. quercina WEST. and BARK), on Quercus coccifera. Zaghouania phillyreae PAT. (new for Sardinia), on Phillyrea angustifolia. Phymatotrichum omnivorum (DUGGAR) HENNEBERT, new on Verbascum thapsus for Sardinia. Guignardia punctoidea (COOKE) SCHROTER (new for Sardinia), on Quercus ilex. Many of the collected species are rare or unknown for the area of investigation until now. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige and N. Ale-Agha.
- Published
- 2010
33. Loss of gap junctional intercellular communication in rat lung epithelial cells exposed to quartz particles.
- Author
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Ale-Agha N, Albrecht C, and Klotz LO
- Subjects
- Animals, Cells, Cultured, Connexin 43 metabolism, Epithelial Cells drug effects, Epithelial Cells metabolism, Lung cytology, Lung metabolism, Phosphorylation, Rats, Silicon Dioxide toxicity, Cell Communication drug effects, Gap Junctions drug effects, Lung drug effects, Quartz toxicity
- Abstract
Chronic inhalation of quartz particles has been implicated in lung diseases including silicosis and cancer. The aim of this study was to investigate whether quartz particles affect gap junctional intercellular communication (GJIC) in rat lung epithelial cells (RLE-6TN). Here, we demonstrate that exposure of RLE-6TN cells to subtoxic doses of DQ12 standard quartz resulted in an up to 55% reduction of GJIC, as determined in a dye transfer assay. We show that connexin-43 (Cx43) is the major connexin responsible for intercellular communication in these lung epithelial cells and that exposure to quartz particles induces a significant internalization of Cx43. Downregulation of GJIC was attenuated by N-acetyl cysteine, suggesting the involvement of reactive oxygen species and/or cellular thiol homeostasis in the regulation of GJIC. Furthermore, an inhibitor of activation of extracellular signal-regulated kinases prevented the loss of GJIC in cells exposed to DQ12 quartz, although no direct phosphorylation of Cx43 upon exposure to DQ12 was detected.
- Published
- 2009
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34. HuR regulates gap junctional intercellular communication by controlling beta-catenin levels and adherens junction integrity.
- Author
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Ale-Agha N, Galban S, Sobieroy C, Abdelmohsen K, Gorospe M, Sies H, and Klotz LO
- Subjects
- Animals, Antineoplastic Agents, Cell Differentiation, Cells, Cultured, Connexin 43 metabolism, Doxorubicin pharmacology, ELAV Proteins, ELAV-Like Protein 1, Epithelial Cells cytology, Epithelial Cells drug effects, Liver cytology, Liver drug effects, Models, Animal, RNA, Messenger metabolism, Rats, Rats, Inbred F344, Tretinoin pharmacology, Adherens Junctions metabolism, Antigens, Surface metabolism, Cell Communication physiology, Epithelial Cells metabolism, Gap Junctions metabolism, Liver metabolism, RNA-Binding Proteins metabolism, beta Catenin metabolism
- Abstract
Unlabelled: Gap junctional intercellular communication (GJIC) plays a critical role in the regulation of tissue homeostasis and carcinogenesis and is modulated by the levels, subcellular localization, and posttranslational modification of gap junction proteins, the connexins (Cx). Here, using oval cell-like rat liver epithelial cells, we demonstrate that the RNA-binding protein HuR promotes GJIC through two mechanisms. First, HuR silencing lowered the levels of Cx43 protein and Cx43 messenger RNA (mRNA), and decreased Cx43 mRNA half-life. This regulation was likely due to the direct stabilization of Cx43 mRNA by HuR, because HuR associated directly with Cx43 mRNA, a transcript that bears signature adenylate-uridylate-rich (AU-rich) and uridylate-rich (U-rich) sequences in its 3'-untranslated region. Second, HuR silencing reduced both half-life and the levels of beta-catenin mRNA, also a target of HuR; accordingly, HuR silencing lowered the levels of whole-cell and membrane-associated beta-catenin. Coimmunoprecipitation experiments showed a direct interaction between beta-catenin and Cx43. Small interfering RNA (siRNA)-mediated depletion of beta-catenin recapitulated the effects of decreasing HuR levels: it attenuated GJIC, decreased Cx43 levels, and redistributed Cx43 to the cytoplasm, suggesting that depletion of beta-catenin in HuR-silenced cells contributed to lowering Cx43 levels at the membrane. Finally, HuR was demonstrated to support GJIC after exposure to a genotoxic agent, doxorubicin, or an inducer of differentiation processes, retinoic acid, thus pointing to a crucial role of HuR in the cellular response to stress and in physiological processes modulated by GJIC., Conclusion: HuR promotes gap junctional intercellular communication in rat liver epithelial cells through two related regulatory processes, by enhancing the expression of Cx43 and by increasing the expression of beta-catenin, which, in turn, interacts with Cx43 and is required for proper positioning of Cx43 at the plasma membrane.
- Published
- 2009
- Full Text
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35. Biodiversity and new records of microfungi in the Ruhrarea (north Rhine Westfalia), Germany.
- Author
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Ale-Agha N, Brassmann M, and Jensen M
- Subjects
- Ascomycota classification, Ascomycota genetics, Ascomycota pathogenicity, Basidiomycota classification, Basidiomycota genetics, Basidiomycota pathogenicity, Biodiversity, Fungi classification, Fungi genetics, Germany, Host-Parasite Interactions, Plant Diseases classification, Plant Leaves microbiology, Viburnum microbiology, Fungi pathogenicity, Mycoses classification, Plant Diseases microbiology, Plants microbiology
- Abstract
During our investigations of the microflora in NRW (Duisburg, Düsseldorf and Essen incl. the greenhouse of the Botanical Garden) in 2007 and 2008, we were able to collect and identify about 55 species on trees, bushes and ornamental plants as parasites and saprophytes. Some of these species are new for Germany or have been only rarely found until now. Most of the species belong the Ascomycotina, Basidiomycotina and Deuteromycotina for example Arthrocladiella mougeotii (Lév.) Vassilkov. on Lycium barbarum L., Caudospora taleola (Fr.) Starb on Quercus robur L., Colletotrichum coffeanum F. Noak on Coffea arabica L. (new for Germany) Colletotrichum trichellum (Fr.) Duke on Hedera helix L., Erysiphe buhrii U. Braun on Lychnis cf. coronaria (L.) Desr. (Anamorph. Oidium dianthi Jacz.), Erysiphe spec. on Acer opalus Mill (new host), Erysiphe flexuosa (Peck) U. Braun & S. Takam. on Aesculus spec. (new for Europe)), Erysiphe heraclei DC. on Tinguarra montana (Webb ex Christ ) A.Hansen & G.Kunkel, Erysiphe necator Schwein. = Uncinula necator (Schwein.) Burrill on Cissus cf. rhombifolia Vahl. (new for NRW), Erysphe trifolii Grev. on Trigonella caerulea (L.) Ser., Golovinomyces cichoracearum (DC.) V.P.Gelyuta (Oidium spec.) on Argyranthemum pinnatifidum (L.f.) R.T. Lowe (new host), Lobatopedis foliicola P.M. Kirk on Quercus robur L. (new for NRW), Lophodermium juniperinum (Fr.) de Not. on Juniperus communis L., Mamiania coryli De Not. on Corylus avellana L., Marssonina juglandis (Lib.) Magnus on Juglans regia L., Oidium hortensia Jørst on Philadelphus coronarius L., Oidium spec. on Dahlia variabilis (Willd.) Desf. (new for Germany), Oidium longipes Noordeloos & Loerak on Petunia hybrida Vilm., Oidium pedilanthi M. Yen on Pedilanthus titymaloides (L.) Poit, Oidium pedaliacearum H.D. Shin sp. nov. (= Oidium sesami H.D. Shin) on Ibicella lutea (Lindl.) van Eselt. (= Martynia lutea Lindl.), Passalora pastinacae (Sacc.) U. Braun = Pseudocercosporella pastinacae (P. Karst.) U. Braun (new for Germany) on Pastinaca sativa L., Podosphaera tridactyla (WalIr.) de Bary on Prunus laurocerasus L., Septoria cornicola Desm. on Cornus sanguinea L., Stigmina tinea (Sacc.) M.B.Ellis on Viburnum opulus L., Torula herbarum (Pers.) Link on Potentilla argentea L., etc. All species are located in the herbarium Mycotheca parva collection G.B. Feige and N. Ale-Agha.
- Published
- 2009
36. Ultraviolet A induced modulation of gap junctional intercellular communication by P38 MAPK activation in human keratinocytes.
- Author
-
Bellei B, Mastrofrancesco A, Briganti S, Aspite N, Ale-Agha N, Sies H, and Picardo M
- Subjects
- Cell Communication physiology, Cell Membrane radiation effects, Cells, Cultured, Connexin 43 genetics, Connexin 43 metabolism, Down-Regulation radiation effects, Gap Junctions physiology, Humans, Keratinocytes radiation effects, Phosphorylation radiation effects, Reactive Oxygen Species metabolism, Signal Transduction radiation effects, p38 Mitogen-Activated Protein Kinases genetics, Cell Communication radiation effects, Gap Junctions radiation effects, Keratinocytes metabolism, Ultraviolet Rays, p38 Mitogen-Activated Protein Kinases metabolism
- Abstract
Aberrant gap junctional intercellular communication (GJIC) has been implicated in tumor development and progression. UltravioletA (UVA)-induced oxidative stress has been associated with skin carcinogenesis. We report a potential link between GJIC and the cellular stress response induced by UVA in normal human keratinocytes (NHK). In this study, UVA irradiation (10 J/cm(2)) compromised GJIC integrity in absence of cytotoxic effects as demonstrated by the absence of cell death and by the reversibility of GJIC down-regulation. Inhibition of communication by UVA was associated with hyperphosphorylation and decreased expression of connexin43 (Cx43), the most abundant gap junction protein expressed by keratinocytes. Cx43 hyperphosphorylation induced by UVA is, at least in part, mediated through mitogen-activated protein kinase (MAPK) activation as Ser279 and Ser282 sites, two downstream direct targets of p38 MAPK were found to be phosphorylated after UVA treatment. However, inhibition of p38 MAPK activity did not significantly protect from cell-cell communication inhibition because of a strong cellular cytotoxicity observed with SB202190 and SB203580, two selective inhibitors of p38 MAPK, in combination with UVA that compromises the outcome of dye transfer assay. By contrast, in Hacat cell line, inhibition of p38 activity reduced both phosphorylation and degradation of Cx43, demonstrating that these events are correlated.
- Published
- 2008
- Full Text
- View/download PDF
37. Rare or remarkable microfungi from Oaxaca (south Mexico)--Part II.
- Author
-
Ale-Agha N, Jensen M, Brassmann M, Kautz S, Eilmus S, and Ballhorn DJ
- Subjects
- Fungi pathogenicity, Mexico, Plants microbiology, Fungi classification, Fungi isolation & purification, Phylogeny, Plant Diseases microbiology
- Abstract
Microfungi were collected in southern Mexico in the vicinity of Puerto Escondido, Oaxaca in 2007. In 2006, samples were gathered from Acacia myrmecophytes [(Remarkable microfungi from Oaxaca of Acacia species) Part I]. In the present investigation [Part II], we collected microfungi from different parts of a variety of wild and cultivated higher plants belonging to the families Anacardiaceae, Caricaceae, Fabaceae, Moraceae, and Nyctaginacae. The microfungi found here live as parasites or saprophytes. Interestingly, the species Colletotrichum lindemuthianum (Sacc. and Magn.) Briosi and Cavara has repeatedly been used to cause fungal infections of Phaseolus lunatus leaves in laboratory experiments. We could now find the same fungus as parasite on the same host plants under field conditions showing that results obtained in the laboratory are also relevant in nature. Most of the fungal species collected belong to the classes Ascomycotina, Basidiomycotina and Deuteromycotina. Until now, some of the microfungi identified in this study have been rarely observed before or have been reported for the first time in Mexico, for example: Pestalotia acaciae Thüm. on Acacia collinsii Safford; Corynespora cassiicola (Berk. and M.A. Curtis) C.T. Wei on Carica papaya L.; Botryosphaeria ribis Grossenb. and Duggar and Cercosporella leucaenae (Raghu Ram and Mallaiah) U. Braun (new for Mexico) and Camptomeris leucaenae (F. Stevens and Dalbey) Syd. (new for Mexico) on Leucaena leucocephala (Lam.) de Wit.; Oidium clitoriae Narayanas. and K. Ramakr. and Phakopsora cf. pachyrhizi Sydow and Sydow (new for Mexico) on Clitoria ternatea L.; Botryosphaeria obtusa (Schw.) Shoemaker on Prosopis juliflora (Sw.) DC.; Cylindrocladium scoparium Morg. on Ficus benjamina L.; Acremonium sp. on Bougainvillea sp. All specimens are located in the herbarium ESS. Mycotheca Parva collection G.B. Feige and N. Ale-Agha.
- Published
- 2008
38. Survey of microfungi in the Kleinwalsertal (Austrian alps).
- Author
-
Jensen M, Ale-Agha N, and Brassmann M
- Subjects
- Austria, Fungi classification, Fungi isolation & purification, Phylogeny, Plant Diseases microbiology
- Abstract
During an excursion to the Alps near the German/Austrian border (Kleinwalsertal) in August 2007, we were able to collect more than 40 species of microfungi as parasites or saprophytes on different parts of wild plants. Some of them have been observed only rarely until now. Most of the species collected belong to the classes Ascomycotina, Basidiomycotina, and Deuteromycotina. For example: -Leptosphaeria jaceae Holm on Centaurea jacea L.; -Mycosphaerella equiseticola Bond.-Mont. on Equisetum telmateia Ehrh.; -Erysiphe cichoracearum DC. on Adenostyles alliariae (Gouan) Kerner, Centaurea phrygia, Cicerbita alpina (L.) Wallr.; -Podosphaera fusca (Fr.) U. Braun comb. nov. on Petasites paradoxus (Retz.) Baumg. and Senecio alpinus (L.) Scop.; -Pirottaea veneta Sacc. and Speg. on Lamium maculatum L.; -Coleosporium tussilaginis (Pers.) Kleb. on Adenostyles alliariae, Petasites paradoxus; -Puccinia mulgedii (West.) Syd. on Cicerbita alpinl; -Titleospora equiseti (Desm.) Vassil., -Stagonospora equiseti Fautr. on Equisetum telmateia, -Valdensia heterodoxa Peyronel on Cicerbita alpina.
- Published
- 2008
39. Epidermal growth factor- and stress-induced loss of gap junctional communication is mediated by ERK-1/ERK-2 but not ERK-5 in rat liver epithelial cells.
- Author
-
Abdelmohsen K, Sauerbier E, Ale-Agha N, Beier J, Walter P, Galban S, Stuhlmann D, Sies H, and Klotz LO
- Subjects
- Animals, Cell Communication drug effects, Cell Line, Connexin 43 metabolism, Epithelial Cells drug effects, Gap Junctions drug effects, Liver cytology, Phosphorylation, Rats, Recombinant Proteins pharmacology, Vitamin K 3 pharmacology, Cell Communication physiology, Epidermal Growth Factor pharmacology, Epithelial Cells physiology, Gap Junctions physiology, Mitogen-Activated Protein Kinase 1 metabolism, Mitogen-Activated Protein Kinase 3 metabolism, Mitogen-Activated Protein Kinase 7 metabolism
- Abstract
Extracellular signal-regulated kinases (ERK) 1 and 2 as well as ERK-5 were previously suggested to phosphorylate connexin-43 and to contribute to the modulation of gap junctional intercellular communication (GJC). Exposure of rat liver epithelial cells to epidermal growth factor (EGF) or the redox cycling and alkylating agent menadione resulted in phosphorylation of connexin-43 and loss in GJC, both of which were abrogated by pharmacological inhibitors of ERK-1/2 activation, if used in concentrations that selectively abrogate phosphorylation of ERK-1/2 but not of ERK-5. Thus, EGF- or menadione-induced loss of GJC is mediated by ERK-1/2 but not ERK-5 in rat liver epithelial cells.
- Published
- 2007
- Full Text
- View/download PDF
40. CD133+ hepatic stellate cells are progenitor cells.
- Author
-
Kordes C, Sawitza I, Müller-Marbach A, Ale-Agha N, Keitel V, Klonowski-Stumpe H, and Häussinger D
- Subjects
- AC133 Antigen, Animals, Cell Differentiation, Cells, Cultured, Male, Rats, Rats, Wistar, Antigens, CD metabolism, Glycoproteins metabolism, Hepatocytes cytology, Hepatocytes metabolism, Peptides metabolism, Stem Cells cytology, Stem Cells metabolism
- Abstract
Hepatic stellate cells (HSC) play an important role in the development of liver fibrosis. Here, we report that HSC express the stem/progenitor cell marker CD133 and exhibit properties of progenitor cells. CD133+ HSC of rats were selected by specific antibodies and magnetic cell sorting. Selected cells displayed typical markers of HSC, endothelial progenitor cells (EPC), and monocytes. In cell culture, CD133+ HSC transformed into alpha-smooth muscle actin positive myofibroblast-like cells, whereas application of cytokines known to facilitate EPC differentiation into endothelial cells led to the formation of branched tube-like structures and induced expression of the endothelial cell markers endothelial nitric oxide synthase and vascular-endothelial cadherin. Moreover, cytokines that guide stem cells to develop hepatocytes led to the appearance of rotund cells and expression of the hepatocyte markers alpha-fetoprotein and albumin. It is concluded that CD133+ HSC are a not yet recognized progenitor cell compartment with characteristics of early EPC. Their potential to differentiate into endothelial or hepatocyte lineages suggests important functions of CD133+ HSC during liver regeneration.
- Published
- 2007
- Full Text
- View/download PDF
41. Remarkable microfungi from Oaxaca (Mexico) of Acacia species.
- Author
-
Ale-Agha N, Jensen M, Koeppen CW, and Hermes M
- Subjects
- Colony Count, Microbial, Mexico, Species Specificity, Acacia microbiology, Fungi classification, Fungi growth & development, Phylogeny, Plant Diseases microbiology
- Abstract
In the state of Oaxaca (Mexico, 10 km north-west of Puerto Escondido 15 degrees 55' N, 97 degrees 09' W) we were able to collect some microfungi living as parasites or saprophytes on Acacia species, some of them are causing attention for Oaxaca. Many belong to the Deuteromycotina (Hyphomycetes, Coelomycetes) and Ascomycotina. On A. hindsii: Calonectria pseudopeziza (Desm.) Sacc., Hypoxylon truncatum (Schwein. Fr.) J.H. Miller, Epicoccum nigrum Link., Zygosporium gibbum (Sacc., M. Roussau & E. Bommer) S.J. Hughes and on A. cornigera: Phyllosticta acaciicola P. Henn., Taeniolella alta (Ehrenb. ex Pers.) S.J. Hughes, Cephaliophora tropica Thaxt., Diplodia mutila (Fr. Fr.) Mont., Pleospora herbarum (Pers. Fr.) Rabenh., Gliocladium roseum Bainier, Ulocladium atrum Preuss., and different others. All species collected are listed in text.
- Published
- 2007
42. Survey of microfungi on Alnus glutinosa (L.) Gaertn. from Münsterland, Germany.
- Author
-
Ale-Agha N, Feige GB, and Brassmann M
- Subjects
- Colony Count, Microbial, Germany, Species Specificity, Alnus microbiology, Fungi classification, Fungi isolation & purification, Phylogeny, Plant Diseases microbiology
- Abstract
During our investigation on microfungi in Antoniusheim, Fleissenbach und Merfelderbruch near Dülmen in Münsterland in the years 2005 and 2006 we were able to collect and identify 25 microfungi on Alnus glutinosa (L.) GAERTN. Among them are some which are very rare in Germany linke Phragmoporthe conformis (Berkley & Broome) Petrak, Cryptosporiopsis alnea (Rostr.) Petr., Prosthecium auctum (Berk. & Broome) Petr., Taphrina alni-incanae (Kun.) Magn. [= T. Amentorum (Sadeback) Rostrup], Cryptodiaporthe oxystoma (Rehm.) Z. Urb., Cladosporium alnicola Bub. & Vleug. [= C. Herbarum (Pers.)], Erysiphe penicillata (Wallr.) Link, Melampsoridium betulinum Kleb., Bacterodesmium longisporum M.B. Ellis, Marssonina alni Karak. Asteroma alneum (Pers.: Fr.) Sutton . All collected species can be found in the text.
- Published
- 2007
43. Surveys of new and rare microfungi in the Düsseltal (North Rhine-Westphalia)--Germany.
- Author
-
Ale-Agha N, Feige GB, Jensen M, Brassmann M, and Kricke R
- Subjects
- Fungi pathogenicity, Germany, Phylogeny, Fungi classification, Fungi isolation & purification, Plant Diseases microbiology, Plants microbiology
- Abstract
In the years 2003 and 2004 we have observed an about 70 hectare large area in the Düsseltal, the eastern part of the Neandertal in North Rhine-Westphalia. There we collected on trees, bushes and herbs and found about 150 microfungi of which some are new for Germany or the entire world. E.g.: Pseudocercospora populigena N. ALE-AGHA, U. BRAUN & G.B. FEIGE on Populus berolinensis; Vialaea insculpta (FR.) SACC. on Ilex aquifolium L.; Passalora amelopsidis (PECK.) U. BRAUN on Parthenocissus quinquefolia (L.) PLANCH.: Pleiochaeta setosa (KIRCHN.) HUGHES on Genista angelica L.; Cercospora mercurialis PASS. on Mercurialis perennis L. (new for NRW); Pleurocytospora vestita PETRAK on Ribes aureum PURSH.; Gonatobotrys simplex CORDA on Lolium perenne L.; Phomatospora berckleyi SACC. on Dactylis glomerata L. and so on. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige & N. Ale-Agha.
- Published
- 2005
44. New, rare and remarkable records of microfungi from the Slovakian Republic.
- Author
-
Feige GB, Ale-Agha N, Jensen M, Brassmann M, Christiaans B, and Kricke R
- Subjects
- Fungi pathogenicity, Phylogeny, Slovakia, Fungi classification, Fungi isolation & purification, Plant Diseases microbiology, Plants microbiology
- Abstract
During an excursion to the Slovakian Republic (lower and upper Tatra) of the Botanical Institute of the University of Essen in 2004 we were able to collect about 150 species of microfungi as parasites or saprophytes on cultivated crops and wild plants. Some of them are new for the entire world and a few of them are new for the Slovakian Republic, e.g: Ramularia liliicola N. Ale-Agha, U. Braun & G.B. Feige on Lilium martagon L.; Septoria aegopodii DESM. Ex Kickx. F. on Aegopodium podagaria L.; Puccinia asarina Kunze on Asarum europaeum L.; Puccinia polygoni ALB. & SCHW. and Puccinia polygoni-amphibii PERS. on Bilderdykia convolvulus (L.) Du Mont.; Ramularia chamaenerii Rostr. and Mycosphaerella chamaenerii Saville on Epilobium angustifolium L.; Plasmopara pusilla (de By.) Schroet on Geranium sylvaticum L.; Cercosporidium depressum (Berk. & Br.) Deighta on Angelica sylvestris L. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige & N. Ale-Agha.
- Published
- 2005
45. New, rare or remarkable microfungi in the Italian Alps (Carnic Alps)--part II--other microfungi.
- Author
-
Ale-Agha N, Feige GB, Jensen M, Christiaans B, Brassmann M, and Kricke R
- Subjects
- Altitude, Ascomycota classification, Ascomycota isolation & purification, Basidiomycota isolation & purification, Climate, Geography, Italy, Plant Diseases microbiology, Fungi classification, Fungi isolation & purification, Plants microbiology
- Abstract
In addition to the collection of Ascomycotina in the Carnic Alps (see New, rare or remarkable microfungi in the Italian Alps (Carnic Alps) part I ) we were able to treasure about 300 species of parasitic and saprophytic microfungi. Among them Basidiomycetes, Ascomycetes and Deuteromycets like Bostrichonema polygoni (UNGER) SCHROT. on Polygonum viviparum L., Chrysomyxa rhododendri DE BY on Picea abies (L.) KARSTEN, Coleosporium tussilaginis (PERS.) BERK. I=C. cacaliae OTTH.] on Adenostyles glabra (MILL.) DC., Dasyscyphus barbatus (KUNZE) MASSEE on Lonicera nigra L., Leptosphaeria coniothyrium (FUCKEL) SACC. on Rosa canina L., Leptotrochila brunellae (LIND) DENNIS on Prunella grandiflora (L.) SCHOLLER., Marssonina kriegeriana (BES.) MAGNUS on Salix reticulata L., Puccinia alpina FUCKEL on Viola biflora L., Puccinia maculosa (STRAUSS.) ROHLING and Erysiphe cichoracearum DC. On Prenanthes purpurea L., Septoria microsora SPENG. on Gentianella germanica (WILLD.) BORNER, Urocystis orobranches (FR.) FISCH. V. WALDH. on Orobranche gracilis SM., Urocystis violae (J. SOWERBY) A. FISCHER VON WALDHEIN on Viola biflora L. and Uromyces phyteumatum (DC.) UNG. on Phyteuma spicatum L. were dominant. All samples are located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.
- Published
- 2004
46. Mycodiversity on a dead stem of the giant hogweed--Heracleum mantegazzianum Sommer et Levier.
- Author
-
Feige GB and Ale-Agha N
- Subjects
- Alternaria isolation & purification, Alternaria pathogenicity, Cladosporium isolation & purification, Cladosporium pathogenicity, Colletotrichum isolation & purification, Colletotrichum pathogenicity, Fungi isolation & purification, Fungi pathogenicity, Plant Diseases microbiology, Heracleum microbiology, Plant Stems microbiology
- Abstract
During our investigations on microfungi in the Ruhr area we were able to find the remarkable mycodiversity of different genera and species on dead stems of Heracleum mantegazzianum, a Neophyt for the European flora. Altemaria alternata (FR.FR.) KEISSL., Camarosporium spec., Cladosporium herbarum (PERS.) LINK, Colletotrichum dematium (PERS. Ex FR.) GOVE, Dactylella armandii YADV., Dasyscyphus mollissimus (LASCH.) DENNIS, Dendryphion comosum WALLR., Endophragmia hyalosperma (CORDA) MORGAN-JONES & COLE, Epicoccum purpurescens EHRENB., Gliomastix luzulae (FUCKEL) MASON, Hymenoscyphus herbarum (PERS.) DENNIS, Lasiosphaeria caudata (FUCKEL) MASON, Lophiostoma caulium (FR.) CES. & de NOT, Periconia byssoides PERS., Phoma complanata (TODE EX FR.) DESM., Phoma longissima (PERS.) WESLEND., Pirottaea cf. nigrostriata GRADDON, Pleospora herbarum (PERS.) RABENH. EX. CES. & de NOT, Pleurophragmium parvisporum (PREUSS) HOLUBOVA-JECHOVA, Pyrenopeziza chailletii FUCKEL, Rhizopus stolonifer (EHRENB. FR.) VUILL, Sclerotina sclerotiorum (LIB.) DE BY., Septofusidium herbarum (BROWN & SMITH) SAMSON, Torula herbarum (PERS.) LINK, Trichoderma koningii OUDEM, Volutella melaloma BERK. & BR. The sample is located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.
- Published
- 2004
47. New and remarkable microfungi in North Rhine Westphalia, Germany.
- Author
-
Ale-Agha N, Feige GB, Christiaans B, Brassmann M, and Balakirew S
- Subjects
- Climate, Fungi classification, Fungi pathogenicity, Germany, Phlomis microbiology, Plant Diseases microbiology, Plant Leaves microbiology, Fungi isolation & purification, Plants microbiology
- Abstract
During our investigation on microfungi in North Rhine Westphalia in the years 2002 and 2003 we were able to collect and identify some new and rare species of microfungi as parasites and saprophytes on wild and ornamental plants. Some of these like Erysiphe elevata (BURILL.) U. BRAUN & S. TAKAMATSU COMB. NOV. [=Microsphaera elevata BURILL.] on Catalpa bignonioides WALT., Erysiphe syringae-japonicae (U. BRAUN) U. BRAUN & S. TAKAMATSU [= Microsphaera syringae-japonicae U. BRAUN, M. aceris BUNKINA. KOMAROVSKIE CHTENIYA, Erysiphe acerina U. BRAUN & S. TAKAMATSU] on Acer campestre L. and Acer barinerve L., Mycosphaerella iridis (DESM.) SCHROET., Ectostroma iridis FR. and Volutella melaloma BERK. & BR on Iris pseudacorus L., Puccinia doronicella P. SYD. & SYD. on Doronicum columnae TEN., Ascochyta lamiorum SACC. S.L. I=A. phlomidis BUB. & WROB.) on Phlomis tuberosa L., Colletotrichum gloeosporides (PENZ.) SACC. on Passiflora coerulea L., Oidium hortensiae JOERST on Hydrangea macrophylla (THUNB.) SER., Puccinia horiana P. HENN. on Chrysanthemum vulgare (L.) BERNH., Lophodermium pinastri (SCHRAD.) CHEV., Leptostroma pinorum SACC., Sclerophoma pythiophila (CDA) HOHN., Lichenoconium boreale (KARST.) PETRAK. & SYD., Anthostomella formosa KIRSCHST. and Sphaeropsis sapinae (FR.) DYKO & SUTTON on Pinus nigra L. are new for Germany. All samples are located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.
- Published
- 2004
48. New, rare or remarkable microfungi in the Italian Alps (Carnic Alps)--part I--ascomycotina.
- Author
-
Feige GB, Ale-Agha N, Jensen M, Christiaans B, and Kricke R
- Subjects
- Altitude, Ascomycota classification, Ascomycota pathogenicity, Italy, Plant Diseases microbiology, Plant Leaves microbiology, Plant Stems microbiology, Wood, Ascomycota isolation & purification, Trees microbiology
- Abstract
During our observations in the SE part of the Carnic Alps in the year 2003 we were able to collect and identify 35 ascomycetes on trees and dead wood. Among these one can find numerous ascomycetes of different orders e.g. Pyrenomycetes, Loculoascomycetes and Discomycetes. Some species like Botryosphaeria ribis GROSENLUCHER & DUGGAR on Ribes alpinum L., Dothiora pyrenophora (FR.) FR. on Sorbus aucuparia L., Gemmamyces piceae (BORTH.) CASAGO. on Picea excelsa (LAM.) LINK, Glomerella montana (SACC.) v. ARX & E. MULLER on Sesleria caerulea (L.) ARD, Hymenoscyphus immutabilis (Fuck.) Dennis on Alnus incana (L.) Moench, Hysterographium fraxini (PERS. Ex. FR.) de Not. on Fraxinus ornus L., Lachnellula willkommii (Hartig) DENNIS [= Trichascyphella willkommii (Hartig) NANNF.] on Larix decidua MILL.,Leptosphaeria lycopodina (Mont.) SACC. on Lycopodium annotinum L., Mollisia adenostylidis REHM. on Adenostyles glabra (MILL.) DC., Pezicula cinnamomea (DC.)SACC. [ana: Cryptosporiopsis quercina PETRAK] on Quercus robur L., Pyrenopeziza petiolaris (A. & S. Ex FR.) NANNF. on Acer pseudoplatanus L., Tapesia rosae (PERS.) FUCKEL on Rosa canina L., are new for this area. All specimen are deposited in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.
- Published
- 2004
49. Modulation of homologous gap junctional intercellular communication of human dermal fibroblasts via a paracrine factor(s) generated by squamous tumor cells.
- Author
-
Stuhlmann D, Ale-Agha N, Reinehr R, Steinbrenner H, Ramos MC, Sies H, and Brenneisen P
- Subjects
- Base Sequence, Child, Child, Preschool, Connexin 43 metabolism, DNA Primers, Down-Regulation, Fibroblasts cytology, Fibroblasts metabolism, Humans, Intercellular Signaling Peptides and Proteins biosynthesis, Skin metabolism, Tumor Cells, Cultured, Cell Communication physiology, Gap Junctions physiology, Intercellular Signaling Peptides and Proteins physiology, Skin cytology
- Abstract
Loss of gap junctional intercellular communication (GJIC) is a characteristic of cancer cells. Since a coordinated interaction of epithelial tumor cells with stromal cells is a prerequisite for tumor invasion and metastasis, the present study was designed to test the hypothesis that skin-derived tumor cells may modulate homologous and heterologous GJIC. While homologous GJIC of human dermal fibroblasts as well as epidermal keratinocytes was detected, no communication was measured between SCL-1 cells derived from squamous cell carcinoma of human skin. Interestingly, co-cultures of dermal fibroblasts and SCL-1 tumor cells in serum-containing medium resulted in a 52-70% lowering of the number of communicating fibroblasts. Furthermore, incubation of confluent fibroblast cultures with serum-free supernatant fractions (20-30 kDa) from tumor cells, termed the 20/30 fraction, lowered the homologous gap junction communication of fibroblasts by >90%. This novel aspect of down-regulated homologous GJIC of dermal fibroblasts, which is reversible, was neither mediated by alteration of the expression of connexin43, the major gap junctional protein of dermal fibroblasts, nor by aberrant localization of connexin43 in the plasma membrane. Furthermore, post-translational modifications of connexins, such as phosphorylation, was not measured by mobility shift studies. Tumor cell-mediated GJIC down-regulation between fibroblasts was suppressed using EGTA-containing serum-free tumor cell-derived supernatants suggesting that calcium ions (Ca2+) might mediate the transduction of this effect. The involvement of Ca2+ in down-regulation of homologous GJIC of fibroblasts was supported by an increase in fluorescence intensity of the intracellular calcium-sensitive indicator Fura-2 upon treatment of fibroblasts with the active 20/30 fraction. In conclusion, these data establish homologous GJIC of (stromal) fibroblasts as a parameter modulated by a paracrine acting factor(s) of epithelial tumor cells during tumor-stroma interaction of skin cells.
- Published
- 2003
- Full Text
- View/download PDF
50. New and remarkable records of microfungi from Turkey.
- Author
-
Ale-Agha N, Feige GB, Christiaans B, and Dündar AE
- Subjects
- Phylogeny, Species Specificity, Turkey, Fungi classification, Fungi isolation & purification, Plants microbiology
- Abstract
During a botanical excursion of the University of Essen in the year 2002 to North-, Central- and South-Anatolia we have collected representatives of about 100 genera of microfungi as parasites or saprophytes on crops and wild plants. Some of them are new for Turkey: Passalora dubia on Atriplex hortensis, Pseudocercospora ligustri on Ligustrum ovalifolium, Passalora smilacis on Smilax aspera, Uromyces limonii on Limonium spec., Puccinia jasmini on Jasminim spec., Sawadea bicornis on Acer negundo, Puccinia sii-falcariae on Falcaria vulgaris, Phomia hedericola on Hedera helix, Camorosporium pistaciae on Pistacia terebinthus, Erysiphe bahrii on Silene spec., Ramularia heraclei on Apium graveolens. All specimens are located in the Herbarium ESS, Mycotheca parva, collection G.B. Feige & N. Ale-Agha.
- Published
- 2003
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