8 results on '"Wiechmann K"'
Search Results
2. In silico discovery of novel acidic microsomal prostaglandin E2 synthase 1 inhibitors from synthetic and natural sources
- Author
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Waltenberger, B., Wiechmann, K., Schuster, D., Russo, Alessandra, Wolber, G., Rollinger, J. M., Werz, O., and H. STUPPNER H.
- Published
- 2010
3. Myrtucommulone from Myrtus communis: metabolism, permeability, and systemic exposure in rats
- Author
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Jeffrey S. Barrett, Antonietta Rossi, Katja Wiechmann, Mona Abdel-Tawab, Jan Hüsch, Lidia Sautebin, Jürgen Meins, Carsten Skarke, Kathleen Gerbeth, Oliver Werz, Manfred Schubert-Zsilavecz, Gerbeth, K, Hüsch, J, Meins, J, Rossi, Antonietta, Sautebin, Lidia, Wiechmann, K, Werz, O, Skarke, C, Barrett, J, Schubert Zsilavecz, M, and Abdel Tawab, M.
- Subjects
Male ,medicine.medical_treatment ,Administration, Oral ,Biological Availability ,Pharmaceutical Science ,Phloroglucinol ,Pharmacology ,Biology ,Permeability ,Analytical Chemistry ,Drug Stability ,Pharmacokinetics ,In vivo ,Oral administration ,Drug Discovery ,medicine ,Animals ,Humans ,Lipoxygenase Inhibitors ,Rats, Wistar ,Prostaglandin-E Synthases ,Arachidonate 5-Lipoxygenase ,Myrtus communis ,Molecular Structure ,Anti-Inflammatory Agents, Non-Steroidal ,Organic Chemistry ,Myrtus ,Rats ,Bioavailability ,Intramolecular Oxidoreductases ,Complementary and alternative medicine ,Microsomes, Liver ,Microsome ,Molecular Medicine ,Caco-2 Cells ,Drug metabolism ,Prostaglandin E - Abstract
Nonsteroidal anti-inflammatory drug intake is associated with a high prevalence of gastrointestinal side effects, and severe cardiovascular adverse reactions challenged the initial enthusiasm in cyclooxygenase-2 inhibitors. Recently, it was shown that myrtucommulone, the active ingredient of the Mediterranean shrub Myrtus communis , dually and potently inhibits microsomal prostaglandin E 2 synthase-1 and 5-lipoxygenase, suggesting a substantial anti-inflammatory potential. However, one of the most important prerequisites for the anti-inflammatory effects in vivo is sufficient bioavailability of myrtucommulone. Therefore, the present study was aimed to determine the permeability and metabolic stability in vitro as well as the systemic exposure of myrtucommulone in rats. Permeation studies in the Caco-2 model revealed apparent permeability coefficient values of 35.9 · 10 −6 cm/s at 37 °C in the apical to basolateral direction, indicating a high absorption of myrtucommulone. In a pilot rat study, average plasma levels of 258.67 ng/mL were reached 1 h after oral administration of 4 mg/kg myrtucommulone. We found that myrtucommulone undergoes extensive phase I metabolism in human and rat liver microsomes, yielding hydroxylated and bihydroxylated as well as demethylated metabolites. Physiologically-based pharmacokinetic modeling of myrtucommulone in the rat revealed rapid and extensive distribution of myrtucommulone in target tissues including plasma, skin, muscle, and brain. As the development of selective microsomal prostaglandin E 2 synthase-1 inhibitors represents an interesting alternative strategy to traditional nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors for the treatment of chronic inflammation, the present study encourages further detailed pharmacokinetic investigations on myrtucommulone.
- Published
- 2012
4. Low-dose, non-supervised, health insurance initiated exercise for the treatment and prevention of chronic low back pain in employees. Results from a randomized controlled trial.
- Author
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Haufe S, Wiechmann K, Stein L, Kück M, Smith A, Meineke S, Zirkelbach Y, Rodriguez Duarte S, Drupp M, and Tegtbur U
- Subjects
- Adult, Chronic Disease, Female, Humans, Male, Middle Aged, Prospective Studies, Exercise, Low Back Pain prevention & control, Low Back Pain therapy
- Abstract
Objective: Back pain is a major problem requiring pragmatic interventions, low in costs for health care providers and feasible for individuals to perform. Our objective was to test the effectiveness of a low-dose 5-month exercise intervention with small personnel investment on low back strength and self-perceived pain., Methods: Two hundred twenty-six employees (age: 42.7±10.2 years) from three mid-size companies were randomized to 5-month non-supervised training at home (3 times/week for 20 minutes) or wait-list-control. Health insurance professionals instructed the participants on trunk exercises at the start and then supervised participants once a month., Results: Muscle strength for back extension increased after the 5-month intervention with a significant between-group difference (mean 27.4 Newton [95%CI 2.2; 60.3]) favoring the exercise group (p = 0.035). Low back pain was reduced more in subjects after exercise than control (mean difference -0.74 cm [95%CI -1.17; -0.27], p = 0.002). No between-group differences were observed for back pain related disability and work ability. After stratified analysis only subjects with preexisting chronic low back pain showed a between-group difference (exercise versus controls) after the intervention in their strength for back extension (mean 55.7 Newton [95%CI 2.8; 108.5], p = 0.039), self-perceived pain (mean -1.42 cm [95%CI -2.32; -0.51], p = 0.003) and work ability (mean 2.1 points [95%CI 0.2; 4.0], p = 0.032). Significant between-group differences were not observed in subjects without low back pain: strength for back extension (mean 23.4 Newton [95%CI -11.2; 58.1], p = 0.184), self-perceived pain (mean -0.48 cm [95%CI -0.99; 0.04], p = 0.067) and work ability (mean -0.1 points [95%CI -0.9; 0.9], p = 0.999). An interaction between low back pain subgroups and the study intervention (exercise versus control) was exclusively observed for the work ability index (p = 0.016)., Conclusion: In middle-aged employees a low-dose, non-supervised exercise program implemented over 20 weeks improved trunk muscle strength and low back pain, and in those with preexisting chronic low back pain improved work ability.
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- 2017
- Full Text
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5. Mitochondrial Chaperonin HSP60 Is the Apoptosis-Related Target for Myrtucommulone.
- Author
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Wiechmann K, Müller H, König S, Wielsch N, Svatoš A, Jauch J, and Werz O
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- Chaperonin 60 chemistry, Chaperonin 60 metabolism, Cytochromes c metabolism, Drug Design, HL-60 Cells, Heat-Shock Response drug effects, Humans, Mitochondria drug effects, Mitochondria metabolism, Mitochondrial Proteins chemistry, Mitochondrial Proteins metabolism, Molecular Targeted Therapy, Phloroglucinol pharmacology, Protein Aggregates drug effects, Apoptosis drug effects, Chaperonin 60 antagonists & inhibitors, Mitochondrial Proteins antagonists & inhibitors, Phloroglucinol analogs & derivatives
- Abstract
The acylphloroglucinol myrtucommulone A (MC) causes mitochondrial dysfunctions by direct interference leading to apoptosis in cancer cells, but the molecular targets involved are unknown. Here, we reveal the chaperonin heat-shock protein 60 (HSP60) as a molecular target of MC that seemingly modulates HSP60-mediated mitochondrial functions. Exploiting an unbiased, discriminative protein fishing approach using MC as bait and mitochondrial lysates from leukemic HL-60 cells as target source identified HSP60 as an MC-binding protein. MC prevented HSP60-mediated reactivation of denatured malate dehydrogenase in a protein refolding assay. Interference of MC with HSP60 was accompanied by aggregation of two proteins in isolated mitochondria under heat shock that were identified as Lon protease-like protein (LONP) and leucine-rich PPR motif-containing protein (LRP130). Together, our results reveal HSP60 as a direct target of MC, proposing MC as a valuable tool for studying HSP60 biology and for evaluating its value as a target in related diseases, such as cancer., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
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- 2017
- Full Text
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6. Imbricaric acid and perlatolic acid: multi-targeting anti-inflammatory depsides from Cetrelia monachorum.
- Author
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Oettl SK, Gerstmeier J, Khan SY, Wiechmann K, Bauer J, Atanasov AG, Malainer C, Awad EM, Uhrin P, Heiss EH, Waltenberger B, Remias D, Breuss JM, Boustie J, Dirsch VM, Stuppner H, Werz O, and Rollinger JM
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- Animals, Anti-Inflammatory Agents isolation & purification, Benzoates isolation & purification, Depsides isolation & purification, Drug Evaluation, Preclinical, HEK293 Cells, Humans, Inhibitory Concentration 50, Leukocytes drug effects, Leukocytes immunology, Male, Mice, Mice, Inbred C57BL, Peritoneum drug effects, Peritoneum immunology, Anti-Inflammatory Agents pharmacology, Ascomycota chemistry, Benzoates pharmacology, Depsides pharmacology
- Abstract
In vitro screening of 17 Alpine lichen species for their inhibitory activity against 5-lipoxygenase, microsomal prostaglandin E2 synthase-1 and nuclear factor kappa B revealed Cetrelia monachorum (Zahlbr.) W.L. Culb. & C.F. Culb. As conceivable source for novel anti-inflammatory compounds. Phytochemical investigation of the ethanolic crude extract resulted in the isolation and identification of 11 constituents, belonging to depsides and derivatives of orsellinic acid, olivetolic acid and olivetol. The two depsides imbricaric acid (4) and perlatolic acid (5) approved dual inhibitory activities on microsomal prostaglandin E2 synthase-1 (IC50 = 1.9 and 0.4 µM, resp.) and on 5-lipoxygenase tested in a cell-based assay (IC50 = 5.3 and 1.8 µM, resp.) and on purified enzyme (IC50 = 3.5 and 0.4 µM, resp.). Additionally, these two main constituents quantified in the extract with 15.22% (4) and 9.10% (5) showed significant inhibition of tumor necrosis factor alpha-induced nuclear factor kappa B activation in luciferase reporter cells with IC50 values of 2.0 and 7.0 µM, respectively. In a murine in vivo model of inflammation, 5 impaired the inflammatory, thioglycollate-induced recruitment of leukocytes to the peritoneum. The potent inhibitory effects on the three identified targets attest 4 and 5 a pronounced multi-target anti-inflammatory profile which warrants further investigation on their pharmacokinetics and in vivo efficacy.
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- 2013
- Full Text
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7. Epitope characterization and crystal structure of GA101 provide insights into the molecular basis for type I/II distinction of CD20 antibodies.
- Author
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Niederfellner G, Lammens A, Mundigl O, Georges GJ, Schaefer W, Schwaiger M, Franke A, Wiechmann K, Jenewein S, Slootstra JW, Timmerman P, Brännström A, Lindstrom F, Mössner E, Umana P, Hopfner KP, and Klein C
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- Amino Acid Sequence, Antibodies, Monoclonal analysis, Antibodies, Monoclonal chemistry, Antibodies, Monoclonal, Humanized, Antibodies, Monoclonal, Murine-Derived chemistry, Antibody Specificity, Antigens, CD20 genetics, Cell Line, Crystallography, X-Ray, Epitope Mapping methods, Epitopes analysis, Humans, Models, Molecular, Mutagenesis, Site-Directed, Protein Structure, Quaternary, Protein Structure, Secondary, Rituximab, Antibodies, Monoclonal classification, Antigens, CD20 chemistry, Antigens, CD20 immunology, Epitopes chemistry
- Abstract
CD20 is a cell-surface marker of normal and malignant B cells. Rituximab, a monoclonal antibody targeting CD20, has improved the treatment of malignant lymphomas. Therapeutic CD20 antibodies are classified as either type I or II based on different mechanisms of killing malignant B cells. To reveal the molecular basis of this distinction, we fine-mapped the epitopes recognized by both types. We also determined the first X-ray structure of a type II antibody by crystallizing the obinutuzumab (GA101) Fab fragment alone and in complex with a CD20 cyclopeptide. Despite recognizing an overlapping epitope, GA101 binds CD20 in a completely different orientation than type I antibodies. Moreover, the elbow angle of GA101 is almost 30° wider than in type I antibodies, potentially resulting in different spatial arrangements of 2 CD20 molecules bound to a single GA101 or rituximab molecule. Using protein tomography, different CD20 complexes were found to be associated with the 2 antibodies, and confocal microscopy showed different membrane compartmentalization of these subpopulations of the cellular CD20 pool. Our findings offer a possible molecular explanation for the different cellular responses elicited by type I and II antibodies.
- Published
- 2011
- Full Text
- View/download PDF
8. Moraxella catarrhalis--infected alveolar epithelium induced monocyte recruitment and oxidative burst.
- Author
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Rosseau S, Wiechmann K, Moderer S, Selhorst J, Mayer K, Krüll M, Hocke A, Slevogt H, Seeger W, Suttorp N, Seybold J, and Lohmeyer J
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- Carcinogens pharmacology, Cell Adhesion physiology, Cell Adhesion Molecules metabolism, Cell Line, Cell Movement physiology, Cytokines metabolism, Epithelium microbiology, Epithelium pathology, Humans, Indoles pharmacology, Inflammation metabolism, Inflammation microbiology, Inflammation pathology, Lipopolysaccharides pharmacology, Lung Diseases metabolism, Lung Diseases microbiology, Lung Diseases pathology, Macrophage Activation, Maleimides pharmacology, Monocytes microbiology, Monocytes pathology, Moraxellaceae Infections pathology, Protein Kinase C antagonists & inhibitors, Protein Kinase C metabolism, Pulmonary Alveoli cytology, Pulmonary Alveoli microbiology, Pulmonary Alveoli pathology, Superoxides metabolism, Tetradecanoylphorbol Acetate pharmacology, Epithelium metabolism, Monocytes metabolism, Moraxella catarrhalis, Moraxellaceae Infections metabolism, Pulmonary Alveoli metabolism, Respiratory Burst physiology
- Abstract
The recruitment of monocytes appears to be a crucial factor for inflammatory lung disease. Alveolar epithelial cells contribute to monocyte influx into the lung, but their impact on monocyte inflammatory capacity is not entirely clear. We thus analyzed the modulation of monocyte oxidative burst by A549 and isolated human alveolar epithelial cells. Epithelial infection with Moraxella catarrhalis induced monocyte adhesion, transepithelial migration, and superoxide generation, whereas stimulation with lipopolysaccharide, tumor necrosis factor-alpha, interleukin-1beta, or interferon-gamma induced adhesion or transmigration, but failed to initiate monocyte burst. The effect of microbial challenge was mimicked by phorbol myristate acetate and inhibited by the protein kinase C inhibitor bisindoylmaleimide. Furthermore, evidence for a role of platelet-activating factor-signaling in monocytes is presented. Monocyte burst was neither induced by supernatant nor affected by fixation of A549 cells, excluding the contribution of epithelium-derived soluble factors but emphasizing the mandatory role of intercellular contact. The employment of blocking antibodies, however, denied a role for the adhesion molecules intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, or CD11b/CD18 and CD49d/CD29. In essence, infection of alveolar epithelial cells with M. catarrhalis might amplify the inflammatory capacity of invading monocytes eliciting their superoxide production. The epithelial response to this microbial challenge thus clearly differed from that to proinflammatory cytokines.
- Published
- 2005
- Full Text
- View/download PDF
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