70 results on '"Kretschmer N"'
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2. Water Quality Assessment of the Mining-Impacted Elqui River Basin, Chile
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Ribeiro, L., Kretschmer, N., Nascimento, J., Buxo, A., Rötting, T. S., Soto, G., Soto, M., Oyarzún, J., Maturana, H., and Oyarzún, R.
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- 2014
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3. Anti-proliferative effects of shikonin derivatives on medullary thyroid carcinoma cell lines: Abstract no. 22
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Hasenoehrl, C., Schwach, G., Tabrizi-Wizsy, Ghaffari N., Kretschmer, N., Bauer, R., and Pfragner, R.
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- 2013
4. In vitro effects of dimethylacrylshikonin on melanoma cells: P-218
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Kretschmer, N., Rinner, B., Deutsch, A., Lohberger, B., Schaider, H., and Bauer, R.
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- 2013
5. Effects of altered gravity on the swimming behaviour of fish
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Hilbig, R., Anken, R.H., Sonntag, G., Höhne, S., Henneberg, J., Kretschmer, N., and Rahmann, H.
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- 2002
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6. Studies on the mechanism of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU)-induced hepatotoxicity: III. Ultrastructural characterization of bile duct injury
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Kretschmer, N. W., Boor, P. J., el Azhary, R. A., Ahmed, A. E., and Reynolds, E. S.
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- 1987
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7. NEXT GENERATION SEQUENCING AND SHIKONIN EFFECTS ON HUMAN PRIMARY ARTICULAR OSTEOARTHRITIS CHONDROCYTES.
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Lohberger, B., Sadoghi, P., Leithner, A., Kretschmer, N., and Steinecker-Frohnwieser, B.
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- 2023
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8. Evaluating piezometric trends using the Mann-Kendall test on the alluvial aquifers of the Elqui River basin, Chile.
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Ribeiro, L., Kretschmer, N., Nascimento, J., Buxo, A., Rötting, T., Soto, G., Señoret, M., Oyarzún, J., Maturana, H., and Oyarzún, R.
- Subjects
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WATER supply , *WATER supply management , *STREAMFLOW , *ALLUVIAL streams , *GROUNDWATER monitoring - Abstract
Today, more than ever, there is a need to implement robust statistical methods to ensure the proper evaluation of water resources data to support decision makers in water resources planning and management. Graphing or mapping data for visualization is the easiest way to communicate trends, especially to a non-technical audience. This paper describes the use of an approach that combines the Mann-Kendall test, Sen slope test and principal component analysis to detect and map the monthly trends of piezometric time series and their magnitude in the period 1979–2008. The data were obtained in 23 shallow wells in the alluvial aquifers of the Elqui River basin in central Chile, an area characterized by scarce water resources and intense agricultural and mining activities. The results show significant downward trends at the majority of the wells. Because groundwater in these shallow wells is highly dependent on the water in the river and its tributaries, the reasons for these downward trends are mainly related to a decrease of streamflow observed in the Elqui River. The streamflow is derived from mountain snowmelt rather than from rainfall, which showed no flow trend during the same period. [ABSTRACT FROM AUTHOR]
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- 2015
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9. A petrol ether extract of the roots of Onosma paniculatum induces cell death in a caspase dependent manner.
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Rinner B, Kretschmer N, Knausz H, Mayer A, Boechzelt H, Hao X, Heubl G, Efferth T, Schaider H, and Bauer R
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AIM OF THE STUDY: Traditional Chinese medicine (TCM) has become very popular in Western countries during the last years. Zicao, a remedy of TCM, has been traditionally used to treat cancer, and, its main constituents, naphthoquinones, have been reported to possess antitumor activity (Chen et al., 2002; Papageorgiou et al., 1999). Here, we prepared extracts of different polarities of Onosma paniculatum Bur. & Franch., a plant which is amongst others used as Zicao, but, much less investigated. The extracts were analyzed concerning their growth inhibitory and apoptosis-inducing activity in various tumor cells. MATERIALS AND METHODS: Cell viability was measured by XTT viability and a growth inhibition assay. Effects on the cell cycle and caspase-3 were determined by flow cytometry. RESULTS: From three different extracts, a petrol ether extract showed significant growth inhibitory effect, cell cycle influence and caspase-3 dependent induction of apoptosis which was time and dose dependent. CONCLUSION: To further determine the activity and mechanism of action of the petrol ether extract, we would like to isolate and identify the active principle and investigate the effects in more detail. [ABSTRACT FROM AUTHOR]
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- 2010
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10. Salvadora persica leaves: phytochemical profile and in vitro -inhibitory activity on inflammatory mediators implicated in periodontal disease.
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Kobetitsch S, Gierlikowska B, Kunert O, Mazen AMA, Raab P, Kretschmer N, Donolo C, Pirker T, Bauer R, Kiss AK, and Pferschy-Wenzig EM
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- Humans, Animals, Mice, Cell Proliferation drug effects, Cell Line, Tumor, Tumor Necrosis Factor-alpha metabolism, Macrophages drug effects, Macrophages metabolism, Dose-Response Relationship, Drug, RAW 264.7 Cells, Interleukin-8 metabolism, Phytochemicals pharmacology, Phytochemicals isolation & purification, Plant Leaves, Plant Extracts pharmacology, Plant Extracts isolation & purification, Anti-Inflammatory Agents pharmacology, Anti-Inflammatory Agents isolation & purification, Salvadoraceae chemistry, Inflammation Mediators metabolism, Inflammation Mediators antagonists & inhibitors, Periodontal Diseases drug therapy, Neutrophils drug effects, Neutrophils metabolism
- Abstract
Context: Virtually all parts of Salvadora persica L. (Salvadoraceae) are used in traditional medicine. The twigs and leaves are used for oral health, but leaves are far less investigated., Objective: This study assesses the oral health-promoting potential of S. persica leaves with emphasis on anti-inflammatory and antiproliferative effects and provides an in depth-characterization of their metabolite profile., Materials and Methods: Hot-water and methanolic S. persica leaf extracts (1, 10, and 100 µg/mL) and their major constituents (5, 10, and 50 µM), were subjected to cellular assays on IL-8 and TNFα release in LPS-stimulated human neutrophils, NO-release in LPS/IFNγ stimulated mouse macrophages, and proliferation of HNO97 human tongue carcinoma cells. Metabolite profiling was performed by UHPLC-HRMS analysis. Major constituents were isolated and structurally elucidated., Results and Discussion: Both extracts showed pronounced anti-inflammatory activity in LPS-stimulated neutrophils. Major identified compound classes were flavonoid glycosides, the glucosinolate glucotropaeolin, phenyl- and benzylglycoside sulfates, and megastigmane glycosylsulfates, the latter ones identified for the first time in S. persica . Glucotropaeolin strongly inhibited the release of IL-8 and TNF-α (13.3 ± 2.0 and 22.7 ± 2.6% of the release of stimulated control cells at 50 µM), while some flavonoids and 3-(3'- O -sulfo-β-d-glucopyranosyloxy)-7,8-dihydro-β-ionone, a newly isolated megastigmane glycosylsulfate, were moderately active. Benzylisothiocyanate, which is likely formed from glucotropaeolin during traditional application of S. persica, showed considerable antiproliferative activity (IC
50 in HNO97 cells: 10.19 ± 0.72 µM) besides strongly inhibiting IL-8 and TNFα release., Conclusions: Glucotropaeolin and benzylisothiocyanate are likely implicated in the oral health-promoting effects of S. persica leaves. The chemistry and pharmacology of the newly identified megastigmane glycosylsulfates should be further evaluated.- Published
- 2024
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11. The Biological Assessment of Shikonin and β,β-dimethylacrylshikonin Using a Cellular Myxofibrosarcoma Tumor Heterogeneity Model.
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Lohberger B, Kaltenegger H, Eck N, Glänzer D, Leithner A, and Kretschmer N
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- Humans, Adult, Signal Transduction, Cell Line, Tumor, Apoptosis, Naphthoquinones pharmacology, Fibrosarcoma
- Abstract
Myxofibrosarcoma (MFS) is a subtype of soft tissue sarcoma of connective tissue, which is characterized by large intra-tumor heterogeneity. Therapy includes surgical resection. Additional chemotherapy is of limited effect. In this study, we demonstrated the potent anticancer activity of shikonin derivatives in our MFS cellular model of tumor heterogeneity for developing a new therapeutic approach. The impact of shikonin and β,β-dimethylacrylshikonin (DMAS) on viability, apoptotic induction, MAPK phosphorylation, and DNA damage response were analyzed by means of two human MFS cell lines, MUG-Myx2a and MUG-Myx2b, derived from a singular tumor tissue specimen. MFS cells showed a dose-dependent inhibition of cell viability and a significant induction of apoptosis. Treatment with shikonin derivatives caused an inhibition of pSTAT3 and an increase in pAKT, pERK, pJNK, and pp38. DMAS and shikonin inhibited the activation of the two master upstream regulators of the DNA damage response, ATR and ATM. MUG-Myx2b, which contains an additional PTEN mutation, was more sensitive in some targets. These data demonstrate the significant antitumorigenic effect of shikonin derivatives in MFS and highlight the importance of intra-tumor heterogeneity in treatment planning.
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- 2023
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12. Discrimination of Zicao Samples Based on DNA Barcoding and HPTLC Fingerprints, and Identification of (22E)-Ergosta-4,6,8(14),22-tetraen-3-one As a Marker Compound.
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Kretschmer N, Durchschein C, Heubl G, Pferschy-Wenzig EM, Kunert O, and Bauer R
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- DNA, Chloroplast, DNA, Plant genetics, DNA Barcoding, Taxonomic methods, Lithospermum genetics
- Abstract
The unambiguous identification of plant material is a prerequisite of rational phytotherapy. Misidentification can even cause serious health problems, as in the case of the Chinese medicinal herb Zicao. Commercial material labelled "Zicao" may be derived from the roots of Arnebia euchroma (ruan zicao), Lithospermum erythrorhizon (ying zicao), or Onosma paniculata (dian zicao). All of these roots contain shikonin derivatives as main bioactive constituents, but ying zicao and dian zicao contain also hepatotoxic pyrrolizidine alkaloids in high amounts. Therefore, the use of A. euchroma with a very low pyrrolizidine alkaloid content is desirable. Confusions of the species occur quite often, indicating an urgent need for an unambiguous identification method. Discrimination of 23 zicao samples has been achieved by analyses of the nuclear internal transcribed spacer ITS2 and trnL-F intergenic spacer of the chloroplast DNA. Data were analyzed using Bioedit, ClustalX, Mega 11 and BLAST. Results indicate that ITS2 barcoding can accurately distinguish Arnebia euchroma from their adulterants. Subsequently, an HPTLC method has been developed allowing a chemical discrimination of the most widely used species. (22E)-Ergosta-4,6,8(14),22-tetraen-3-one has been identified as characteristic marker compound, allowing an unambiguous discrimination of A. euchroma and L. erythrorhizon., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)
- Published
- 2023
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13. Cytotoxicity of Carvotacetones from Sphaeranthus africanus Against Cancer Cells and Their Potential to Induce Apoptosis.
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Tran HT, Kretschmer N, Huynh L, and Bauer R
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- Cell Line, Tumor, Apoptosis, Asteraceae, Kidney Neoplasms drug therapy
- Abstract
Three carvotacetones (1 - 3: ) isolated from Sphaeranthus africanus were screened in 60 cancer cell lines at the National Cancer Institute (NCI) within the Developmental Therapeutics Program (DTP). At the concentration of 10
-5 M, compound 1: (3,5-diangeloyloxy-7-hydroxycarvotacetone) turned out to be the most active compound against ACHN and UO-31 renal cancer cell lines with growth percent values of - 100% (all cells dead). Compound 2: (3-angeloyloxy-5-[2″,3″-epoxy-2″-methylbutanoyloxy]-7-hydroxycarvotacetone) showed strong effects in SK-MEL-5 melanoma and ACHN renal cancer cells with inhibition values of 93% and 97%, respectively. Compound 3: (3-angeloyloxy-5-[3″-chloro-2″-hydroxy-2″-methylbutanoyloxy]-7-hydroxy-carvotacetone) exhibited a quite strong effect on renal cancer cells with a growth inhibitory effect of 96% against ACHN and UO-31 cells. When treated with five different concentrations of 1: (1 × 10-8 , 1 × 10-7 , 1 × 10-6 , 1 × 10-5 , and 1 × 10-4 M), HOP-92 cells were found to be most sensitive with GI50 , TGI, and LC50 values of 0.17, 0.40, and 0.96 µM, respectively. When using the ApoTox-Glo triplex assay to evaluate the apoptosis inducing effects of seven carvotacetones isolated from S. africanus in CCRF-CEM cells, compounds 1: - 6: increased caspase-3/7 activity with 1, 2: , and 4: (3-angeloyloxy-5,7-dihydroxycarvotacetone) exhibiting the highest activitiy, indicating induction of caspase-dependent apoptosis., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)- Published
- 2023
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14. Shikonin derivatives cause apoptosis and cell cycle arrest in human chondrosarcoma cells via death receptors and MAPK regulation.
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Lohberger B, Glänzer D, Kaltenegger H, Eck N, Leithner A, Bauer R, Kretschmer N, and Steinecker-Frohnwieser B
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- Apoptosis drug effects, Cell Cycle Checkpoints drug effects, Cell Line, Tumor, Humans, Bone Neoplasms drug therapy, Bone Neoplasms metabolism, Bone Neoplasms pathology, Chondrosarcoma drug therapy, Chondrosarcoma metabolism, Chondrosarcoma pathology, Mitogen-Activated Protein Kinases, Naphthoquinones pharmacology, Receptors, Death Domain metabolism
- Abstract
Background: Although chondrosarcoma is the second most common primary malignant bone tumor, treatment options are limited due to its extensive resistance to a chemo- and radiation therapy. Since shikonin has shown potent anticancer activity in various types of cancer cells, it represents a promising compound for the development of a new therapeutic approach., Methods: The dose-relationships of shikonin and its derivatives acetylshikonin and cyclopropylshikonin on two human chondrosarcoma cell lines were measured using the CellTiter-Glo®. The changes in the cell cycle were presented by flow cytometry. Protein phosphorylation and expression apoptotic markers, MAPKs and their downstream targets were analyzed using western blotting and gene expression were evaluated using RT-qPCR., Results: Chondrosarcoma cells showed a dose-dependent inhibition of cell viability after treatment with shikonin and its derivatives, with the strongest effect for shikonin and IC
50 values of 1.3 ± 0.2 µM. Flow cytometric measurements revealed a G2 /M arrest of the cells after treatment. Protein and gene expression analysis demonstrated a dose-dependent downregulation of survivin and XIAP, and an upregulation of Noxa, γH2AX, cleaved caspase-8, -9, -3, and -PARP. Furthermore, the expression of various death receptors was modulated. As MAPK signaling pathways play a key role in tumor biology, their phosphorylation pattern and their corresponding downstream gene regulation were analyzed. Treatment with shikonin derivatives caused an inhibition of pSTAT3 and an increase of pAKT and the MAPKs pERK, pJNK, and pp38 in a dose-dependent manner., Conclusions: These data demonstrated the significant anti-tumorigenic effect of shikonin derivatives in chondrosarcoma and encourage further research., (© 2022. The Author(s).)- Published
- 2022
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15. Structural Diversity of Complex Phloroglucinol Derivatives from Eucalyptus Species.
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Faezeh Taghizadeh S, Panahi A, Esmaeilzadeh Kashi M, Kretschmer N, Asili J, Ahmad Emami S, Azizi M, and Shakeri A
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- Medicine, Traditional, Phloroglucinol chemistry, Plant Extracts chemistry, Eucalyptus chemistry, Myrtaceae
- Abstract
Several species of the genus Eucalyptus are used in many traditional medicine systems for the treatment of respiratory tract infections, colds, flu, sore throats, and bronchitis. The genus Eucalyptus (Myrtaceae) is a well-known natural source of bioactive phloroglucinols. These polyphenolic compounds bear an aromatic phenyl ring with three hydroxy groups (1,3,5-trihydroxybenzene) which have been exhibiting a variety of biological activities such as antimicrobial, anticancer, anti-allergic, anti-inflammatory, and antioxidant activities. This review summarizes the literature published from 1997 until the end of 2021 and addresses the structure diversity of phloroglucinols isolated from Eucalyptus species and their biological activities. Phloroglucinol-terpene adducts are the main class of compounds that have been reported in this genus., (© 2022 Wiley-VHCA AG, Zurich, Switzerland.)
- Published
- 2022
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16. SK119, a Novel Shikonin Derivative, Leads to Apoptosis in Melanoma Cell Lines and Exhibits Synergistic Effects with Vemurafenib and Cobimetinib.
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Kretschmer N, Durchschein C, Hufner A, Rinner B, Lohberger B, and Bauer R
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- Apoptosis, Azetidines, Cell Line, Humans, Naphthoquinones, Piperidines, Proto-Oncogene Proteins B-raf genetics, Vemurafenib pharmacology, Vemurafenib therapeutic use, Melanoma metabolism, Skin Neoplasms genetics
- Abstract
Melanoma is a complex and heterogenous disease, displays the deadliest form of skin cancer, and accounts for approx. 80% of all skin cancer deaths. In this study, we reported on the synthesis and pharmacological effects of a novel shikonin derivative (SK119), which is active in a nano-molar range and exhibits several promising in vitro effects in different human melanoma cells. SK119 was synthesized from shikonin as part of our search for novel, promising shikonin derivatives. It was screened against a panel of melanoma and non-tumorigenic cell lines using XTT viability assays. Moreover, we studied its pharmacological effects using apoptosis and Western blot experiments. Finally, it was combined with current clinically used melanoma therapeutics. SK119 exhibited IC
50 values in a nano-molar range, induced apoptosis and led to a dose-dependent increase in the expression and protein phosphorylation of HSP27 and HSP90 in WM9 and MUG-Mel 2 cells. Combinatorial treatment, which is highly recommended in melanoma, revealed the synergistic effects of SK119 with vemurafenib and cobimetinib. SK119 treatment changed the expression levels of apoptosis genes and death receptor expression and exhibited synergistic effects with vemurafenib and cobimetinib in human melanoma cells. Further research indicates a promising potential in melanoma therapy.- Published
- 2022
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17. Shikonin Derivatives Inhibit Inflammation Processes and Modulate MAPK Signaling in Human Healthy and Osteoarthritis Chondrocytes.
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Lohberger B, Kaltenegger H, Eck N, Glänzer D, Sadoghi P, Leithner A, Bauer R, Kretschmer N, and Steinecker-Frohnwieser B
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- Cells, Cultured, Chondrocytes metabolism, Humans, Inflammation drug therapy, Inflammation metabolism, Cartilage, Articular metabolism, Naphthoquinones metabolism, Naphthoquinones pharmacology, Osteoarthritis metabolism
- Abstract
Osteoarthritis (OA) is the most common joint disorder and is characterized by the degeneration of articular cartilage. To develop new therapeutic approaches, we investigated the effect of shikonin derivatives on inflammation, MMP expression, and the regulation of MAPK signaling in human healthy (HC) and OA chondrocytes (pCH-OA). Viability was analyzed using the CellTiter-Glo
® Assay. Inflammatory processes were investigated using a proteome profiler™ assay. Furthermore, we analyzed the effects of the shikonin derivatives by protein expression analysis of the phosphorylation pattern and the corresponding downstream gene regulation using RT-qPCR. Both HC and pCH-OA showed a dose-dependent decrease in viability after treatment. The strongest effects were found for shikonin with IC50 values of 1.2 ± 0.1 µM. Shikonin counteracts the inflammatory response by massively reducing the expression of the pro-inflammatory mediators. The phosphorylation level of ERK changed slightly. pJNK and pp38 showed a significant increase, and the downstream targets c/EBPs and MEF2c may play a role in the cartilage homeostasis. STAT3 phosphorylation decreased significantly and has a chondroprotective function through the regulation of cyclin D1 and Sox9. Our results demonstrate for the first time that shikonin derivatives have extensive effects on the inflammatory processes, MAPKs, and IL6/STAT3 downstream regulation in healthy and OA chondrocytes.- Published
- 2022
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18. MUG Mel3 Cell Lines Reflect Heterogeneity in Melanoma and Represent a Robust Model for Melanoma in Pregnancy.
- Author
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Schrom S, Hebesberger T, Wallner SA, Anders I, Richtig E, Brandl W, Hirschmugl B, Garofalo M, Bernecker C, Schlenke P, Kashofer K, Wadsack C, Aigelsreiter A, Heitzer E, Riedl S, Zweytick D, Kretschmer N, Richtig G, and Rinner B
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- Adult, Animals, Cell Line, Cell Line, Tumor, Female, Humans, Lactoferrin pharmacology, Lymphatic Metastasis, Melanoma drug therapy, Melanoma genetics, Mice, Mice, Inbred NOD, Pregnancy, Primary Cell Culture, Proto-Oncogene Proteins B-raf genetics, Skin Neoplasms pathology, Xenograft Model Antitumor Assays methods, Cell Culture Techniques methods, Melanoma metabolism
- Abstract
Melanomas are aggressive tumors with a high metastatic potential and an increasing incidence rate. They are known for their heterogeneity and propensity to easily develop therapy-resistance. Nowadays they are one of the most common cancers diagnosed during pregnancy. Due to the difficulty in balancing maternal needs and foetal safety, melanoma is challenging to treat. The aim of this study was to provide a potential model system for the study of melanoma in pregnancy and to illustrate melanoma heterogeneity. For this purpose, a pigmented and a non-pigmented section of a lymph node metastasis from a pregnant patient were cultured under different conditions and characterized in detail. All four culture conditions exhibited different phenotypic, genotypic as well as tumorigenic properties, and resulted in four newly established melanoma cell lines. To address treatment issues, especially in pregnant patients, the effect of synthetic human lactoferricin-derived peptides was tested successfully. These new BRAF -mutated MUG Mel3 cell lines represent a valuable model in melanoma heterogeneity and melanoma pregnancy research. Furthermore, treatment with anti-tumor peptides offers an alternative to conventionally used therapeutic options-especially during pregnancy.
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- 2021
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19. Synthesis and Pharmacological In Vitro Investigations of Novel Shikonin Derivatives with a Special Focus on Cyclopropane Bearing Derivatives.
- Author
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Kretschmer N, Hufner A, Durchschein C, Popodi K, Rinner B, Lohberger B, and Bauer R
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- Cell Line, Tumor, Humans, Melanoma metabolism, Antineoplastic Agents chemical synthesis, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Apoptosis drug effects, Cyclopropanes chemical synthesis, Cyclopropanes chemistry, Cyclopropanes pharmacology, Melanoma drug therapy, Naphthoquinones chemical synthesis, Naphthoquinones chemistry, Naphthoquinones pharmacology
- Abstract
Melanoma is the deadliest form of skin cancer and accounts for about three quarters of all skin cancer deaths. Especially at an advanced stage, its treatment is challenging, and survival rates are very low. In previous studies, we showed that the constituents of the roots of Onosma paniculata as well as a synthetic derivative of the most active constituent showed promising results in metastatic melanoma cell lines. In the current study, we address the question whether we can generate further derivatives with optimized activity by synthesis. Therefore, we prepared 31, mainly novel shikonin derivatives and screened them in different melanoma cell lines (WM9, WM164, and MUG-Mel2 cells) using the XTT viability assay. We identified ( R )-1-(1,4-dihydro-5,8-dihydroxy-1,4-dioxonaphthalen-2-yl)-4-methylpent-3-enyl 2-cyclopropyl-2-oxoacetate as a novel derivative with even higher activity. Furthermore, pharmacological investigations including the ApoToxGlo
TM Triplex assay, LDH assay, and cell cycle measurements revealed that this compound induced apoptosis and reduced cells in the G1 phase accompanied by an increase of cells in the G2/M phase. Moreover, it showed hardly any effects on the cell membrane integrity. However, it also exhibited cytotoxicity against non-tumorigenic cells. Nevertheless, in summary, we could show that shikonin derivatives might be promising drug leads in the treatment of melanoma.- Published
- 2021
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20. Preparation of new 1,3-dibenzyl tetrahydropyridinylidene ammonium salts and their antimicrobial and anticellular activities.
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Petritsch M, Seebacher W, Mohsin NU, Dolensky J, Hochegger P, Kaiser M, Mäser P, Belaj F, Saf R, Kretschmer N, Alajlani M, Brantner A, Bauer R, Schühly W, and Weis R
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- Animals, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents chemistry, Antifungal Agents chemical synthesis, Antifungal Agents chemistry, Antimalarials chemical synthesis, Antimalarials chemistry, Antineoplastic Agents chemical synthesis, Antineoplastic Agents chemistry, Candida albicans drug effects, Cell Line, Cell Proliferation drug effects, Cell Survival drug effects, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Epidermis drug effects, Escherichia coli drug effects, Female, Humans, Mice, Microbial Sensitivity Tests, Molecular Structure, Parasitic Sensitivity Tests, Plasmodium falciparum drug effects, Pseudomonas aeruginosa drug effects, Quaternary Ammonium Compounds chemical synthesis, Quaternary Ammonium Compounds chemistry, Rats, Salts chemical synthesis, Salts chemistry, Salts pharmacology, Staphylococcus aureus drug effects, Structure-Activity Relationship, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Antimalarials pharmacology, Antineoplastic Agents pharmacology, Quaternary Ammonium Compounds pharmacology
- Abstract
New 1,3 dibenzyl -tetrahydropyridinylidene ammonium salts have been prepared from unsubstituted or N-benzylated tetrahydropyridinylidene ammonium salts. The antiplasmodial and antitrypanosomal activities as well as their cytotoxic effects were determined using microplate assays. In addition, their activities against two gram positive and two gram negative bacteria strains and a yeast strain were examined. Furthermore, anticancer effects against two cell lines were investigated. Physicochemical parameters were calculated and structure-activity-relationships discussed. One compound showed antiplasmodial activity against a multiresistant strain of Plasmodium falciparum in subnanomolar concentration. Antitrypanosomal activities were detected in low nanomolar concentrations. A single compound was active against grampositive and gramnegative bacteria, as well as yeast. One compound inhibited the growth of a HCT cell line in low concentration., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)
- Published
- 2021
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21. Psychological care in children and adolescents with type 1 diabetes in a real-world setting and associations with metabolic control.
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Galler A, Hilgard D, Bollow E, Hermann T, Kretschmer N, Maier B, Mönkemöller K, Schiel R, and Holl RW
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- Adolescent, Blood Glucose metabolism, Child, Delivery of Health Care methods, Delivery of Health Care standards, Diabetes Mellitus, Type 1 blood, Diabetes Mellitus, Type 1 complications, Diabetes Mellitus, Type 1 epidemiology, Female, Germany epidemiology, Humans, Male, Mental Disorders blood, Mental Disorders complications, Mental Disorders epidemiology, Psychological Distress, Psychology, Child methods, Diabetes Mellitus, Type 1 therapy, Glycemic Control psychology, Glycemic Control statistics & numerical data, Mental Disorders therapy, Practice Patterns, Physicians' statistics & numerical data
- Abstract
Background: International guidelines recommend psychosocial care for children and adolescents with type 1 diabetes., Objective: To assess psychological care in children and adolescents with type 1 diabetes in a real-world setting and to evaluate associations with metabolic outcome., Methods: Delivery of psychological care, HbA1c, and rates of severe hypoglycemia and diabetic ketoacidosis (DKA) in children and adolescents with type 1 diabetes from 199 diabetes care centers participating in the German diabetes survey (DPV) were analyzed., Results: Overall, 12 326 out of 31 861 children with type 1 diabetes were supported by short-term or continued psychological care (CPC). Children with psychological care had higher HbA1c (8.0% vs 7.7%, P<.001) and higher rates of DKA (0.032 vs 0.021 per patient-year, P<.001) compared with children without psychological care. In age-, sex-, diabetes duration-, and migratory background-matched children, HbA1c stayed stable in children supported by CPC during follow-up (HbA1c 8.5% one year before psychological care started vs 8.4% after two years, P = 1.0), whereas HbA1c was lower but increased significantly by 0.3% in children without psychological care (HbA1c 7.5% vs 7.8% after two years, P <.001). Additional HbA1c-matching showed that the change in HbA1c during follow-up was not different between the groups, but the percentage of children with severe hypoglycemia decreased from 16.3% to 10.7% in children receiving CPC compared with children without psychological care (5.5% to 5.8%, P =.009)., Conclusions: In this real-world setting, psychological care was provided to children with higher HbA1c levels. CPC was associated with stable glycemic control and less frequent severe hypoglycemia during follow-up., (© 2020 The Authors. Pediatric Diabetes published by John Wiley & Sons Ltd.)
- Published
- 2020
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22. Periplocin mediates TRAIL-induced apoptosis and cell cycle arrest in human myxofibrosarcoma cells via the ERK/p38/JNK pathway.
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Lohberger B, Bernhart E, Stuendl N, Glaenzer D, Leithner A, Rinner B, Bauer R, and Kretschmer N
- Abstract
Background: Periploca sepium is traditionally used in Chinese medicine to treat particularly rheumatic disorders and as a tonic. Periplocin was found as the most cytotoxic compound of its root bark and induced death receptor mediated apoptosis in liposarcoma cells. Sarcomas are a rare type of cancer with only a few treatment options. The five-year survival rate of advanced tumors is low., Purpose: In this study, we investigated the effects of periplocin in two myxofibrosarcoma (MFS)cell lines, MUG-Myx2a and MUG-Myx2b, which are subclones of the same tumor and reflect the tumor´s heterogeneity, and in T60 primary myxofibrosarcoma cells., Methods: The xCELLigence system and the CellTiter 96® AQ
ueous assay were used for studying cell viability. FACS and Western blot experiments were used to investigate the effects of periplocin on apoptosis induction, cell cycle distribution, and the expression of cleaved PARP, caspase 3, p53, phospho-histone γH2AX, ERK/phospho ERK, p38/phospho p38, and, finally, JNK/phospho JNK. Additionally, the expression of the apoptotic markers Bim, NOXA, Bak, Bcl-2, Bcl-xl, and the death receptors IGFR, FADD, TRADD, TNFR1A, TRAIL-R1, and TRAIL-R2 were evaluated using reversed real-time PCR., Results: Periplocin decreased dose-dependently the viability of all MFS cell lines and was more effective than the standard chemotherapeutic doxorubicin. It arrested the cells in the G2/M phase and led to caspase activation. Moreover, periplocin increased the mRNA expression of NOXA, Bak, Bcl-2, and death receptors such as TRAIL-R1 and TRAIL-R2 and the protein expression of ERK/phospho ERK, p38/phospho p38, and JNK/phospho JNK. In all cases, differences in the effects in the different subclones were observed., Conclusion: Periplocin showed promising effects in MFS cells. The higher effectiveness compared to doxorubicin is an important aspect for further research with regard as a treatment option. The different effects of periplocin in the two subclones showed the great importance of intratumoral heterogeneity in MFS therapy., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 The Authors. Published by Elsevier GmbH.. All rights reserved.)- Published
- 2020
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23. β,β-Dimethylacrylshikonin Induces Apoptosis in Melanoma Cell Lines by NOXA Upregulation.
- Author
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Stallinger A, Kretschmer N, Kleinegger F, Brvar L, Liegl-Atzwanger B, Prokesch A, Durchschein C, Bauer R, Deutsch A, and Rinner B
- Subjects
- Apoptosis drug effects, Caspase 3 chemistry, Cell Line, Tumor, Cell Survival drug effects, Humans, Mitochondria drug effects, Mitochondria metabolism, Molecular Structure, Mutation, Naphthoquinones metabolism, Signal Transduction drug effects, Up-Regulation, Caspase 3 metabolism, Melanoma drug therapy, Naphthoquinones pharmacology
- Abstract
Melanoma is the most aggressive form of skin cancer, with high metastasis rates and poor prognosis. Survival rates and possible therapies depend on the state of the tumor and its mutational profile. BRAF and NRAS are the most frequent driver mutations. Currently, there is no efficient therapy for NRAS-mutated or late-stage melanoma. In this study, the therapeutic potential of β,β-dimethylacrylshikonin (DMAS) was investigated on melanoma. The influence of DMAS was determined in five different melanoma cell lines with different mutational profiles. The effects of this compound on cell viability, apoptosis, and gene and protein expression were examined. The results obtained were validated in vivo. DMAS significantly reduced the viability of several melanoma cell lines in a concentration- and time-dependent manner. Furthermore, DMAS induced caspase-3-dependent apoptosis via NOXA upregulation, as confirmed by NOXA knockdown experiments. This is the first time that NOXA -dependent apoptosis was shown with respect to a shikonin derivative and melanoma. Additionally, tumor regression and necrosis under DMAS treatment were demonstrated in vivo. Importantly, BRAF as well as NRAS-mutated metastatic human melanoma cell lines were treated successfully in vitro and in vivo. Taken together, DMAS showed promising results and is worthy of further study.
- Published
- 2020
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24. Naphthoquinone Derivatives Isolated from Plants: Recent Advances in Biological Activity.
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Ahmadi ES, Tajbakhsh A, Iranshahy M, Asili J, Kretschmer N, Shakeri A, and Sahebkar A
- Subjects
- Anti-Infective Agents chemistry, Anti-Infective Agents isolation & purification, Anti-Infective Agents pharmacology, Apoptosis drug effects, Drug Screening Assays, Antitumor, Fungi drug effects, Humans, Naphthoquinones isolation & purification, Naphthoquinones pharmacology, Naphthoquinones therapeutic use, Neoplasms drug therapy, Plants metabolism, Structure-Activity Relationship, Naphthoquinones chemistry, Plants chemistry
- Abstract
Naturally occurring naphthoquinones (NQs) comprising highly reactive small molecules are the subject of increasing attention due to their promising biological activities such as antioxidant, antimicrobial, apoptosis-inducing activities, and especially anticancer activity. Lapachol, lapachone, and napabucasin belong to the NQs and are in phase II clinical trials for the treatment of many cancers. This review aims to provide a comprehensive and updated overview on the biological activities of several new NQs isolated from different species of plants reported from January 2013 to January 2020, their potential therapeutic applications and their clinical significance., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2020
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25. C13 Megastigmane Derivatives From Epipremnum pinnatum: β-Damascenone Inhibits the Expression of Pro-Inflammatory Cytokines and Leukocyte Adhesion Molecules as Well as NF-κB Signaling.
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Pan SP, Pirker T, Kunert O, Kretschmer N, Hummelbrunner S, Latkolik SL, Rappai J, Dirsch VM, Bochkov V, and Bauer R
- Abstract
In order to identify active constituents and to gain some information regarding their mode of action, extracts from leaves of Epipremnum pinnatum were tested for their ability to inhibit inflammatory gene expression in endothelial- and monocyte-like cells (HUVECtert and THP-1, respectively). Bioactivity-guided fractionation using expression of PTGS2 (COX-2) mRNA as a readout resulted in the isolation of two C13 megastigmane glycosides, gusanlungionoside C ( 1 ) and citroside A ( 3 ), and the phenylalcohol glycoside phenylmethyl-2- O -(6- O -rhamnosyl)-ß-D-galactopyranoside ( 2 ). Further analysis identified six additional megastigmane glycosides and the aglycones β-damascenone ( 10 ), megastigmatrienone ( 11 ), 3-hydroxy-β-damascenone ( 12 ), and 3-oxo-7,8-dihydro-α-ionol ( 13 ). Pharmacological analysis demonstrated that 10 inhibits LPS-stimulated induction of mRNAs encoding for proinflammatory cytokines and leukocyte adhesion molecules, such as TNF-α, IL-1β, IL-8, COX-2, E-selectin, ICAM-1, and VCAM-1 in HUVECtert and THP-1 cells. 10 inhibited induction of inflammatory genes in HUVECtert and THP-1 cells treated with different agonists, such as TNF-α, IL-1β, and LPS. In addition to mRNA, also the upregulation of inflammatory proteins was inhibited by 10 as demonstrated by immune assays for cell surface E-selectin and secreted TNF-α. Finally, using a luciferase reporter construct, it was shown, that 10 inhibits NF-κB-dependent transcription. Therefore, we hypothesize that inhibition of NF-κB by β-damascenone ( 10 ) may represent one of the mechanisms underlying the in vitro anti-inflammatory activity of Epipremnum pinnatum extracts., (Copyright © 2019 Pan, Pirker, Kunert, Kretschmer, Hummelbrunner, Latkolik, Rappai, Dirsch, Bochkov and Bauer.)
- Published
- 2019
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26. Anti-inflammatory and antiproliferative compounds from Sphaeranthus africanus.
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Tran HT, Gao X, Kretschmer N, Pferschy-Wenzig EM, Raab P, Pirker T, Temml V, Schuster D, Kunert O, Huynh L, and Bauer R
- Subjects
- Animals, Anti-Inflammatory Agents chemistry, Antineoplastic Agents, Phytogenic chemistry, Cell Line, Cell Line, Tumor, Cyclooxygenase 2 chemistry, Cyclooxygenase 2 genetics, Cyclooxygenase 2 metabolism, Cyclooxygenase Inhibitors chemistry, Drug Evaluation, Preclinical, Humans, Macrophages drug effects, Molecular Docking Simulation, Molecular Structure, Plant Components, Aerial chemistry, Plants, Medicinal chemistry, Anti-Inflammatory Agents pharmacology, Antineoplastic Agents, Phytogenic pharmacology, Asteraceae chemistry, Cyclooxygenase Inhibitors pharmacology
- Abstract
Background: Sphaeranthus africanus has been used in traditional Vietnamese medicine to treat sore throat, and to relieve pain and swelling. However, the anti-inflammatory activity of this plant had not yet been investigated. Previously, we isolated five carvotacetones (1-5) from this plant that displayed cytotoxicity against several cancer cell lines., Purpose: The objective of this study was to isolate further constituents from S. africanus and to investigate the anti-inflammatory activity of all constituents. Furthermore, the anti-proliferative activity of the newly isolated compounds was evaluated., Study Design and Methods: Compounds were isolated from the upper parts of S. africanus by chromatographic methods. Structures were determined using spectroscopic techniques, like NMR and MS. All nine compounds isolated from S. africanus were evaluated for inhibitory activity against COX-1 and COX-2 isoenzymes in-vitro, COX-2 mRNA expression and influence on NO production. The anti-proliferative activities of newly isolated compounds (6-9) were evaluated by XTT viability assay with four cancer cell lines, namely CCRF-CEM, MDA-MB-231, HCT-116, and U-251 cells., Results: Two diastereomeric carvotacetones (3-angeloyloxy-5-[2″S,3″R-dihydroxy-2″-methyl-butanoyloxy]-7-hydroxycarvotacetone (6) and 3-angeloyloxy-5-[2″R,3″R-dihydroxy-2″-methyl-butanoyloxy]-7-hydroxycarvotacetone (7), asperglaucide (8) and chrysoplenol D (9) were isolated from S. africanus. COX-1 and COX-2 assays of compounds 1-9 revealed that compounds 1 and 2 possess potent and selective COX-2 inhibitory activity with IC
50 values of 3.6 and 0.5 μM, respectively. COX-2 gene expression assay showed that some carvotacetones exhibited inhibitory effects on COX-2 gene expression in THP-1 macrophages. Compound 4 is the most active compound inhibiting the synthesis of COX-2 by 55% at 2.06 μM. In the iNOS assay, all seven carvotacetones inhibited NO production in BV2 and RAW cell lines with IC50 values ranging from 0.2 to 2.9 μM. Compound 4 showed potent inhibitory activity with IC50 values of 0.2 μM in both BV2 and RAW cell lines. Molecular docking studies revealed the binding orientations of 1 and 2 in the active sites of COX-2. XTT assay of the newly isolated compounds revealed that the two isomeric carvotacetones (6-7) exhibited considerable anti-proliferative activity against four cancer cell lines (CCRF-CEM, MDA-MB-231, HCT-116, U-251) with IC50 values ranging from 1.23 to 8 μM., Conclusion: For the first-time, the diastereomeric carvotacetones (6-7) were isolated as separate compounds, and their anti-proliferative activity was determined. Selective COX-2 inhibitory, COX-2 mRNA expression and NO production inhibitory activities by some of the major constituents of S. africanus supports the traditional medical application of this plant for the treatment of inflammation-related disorders., (Copyright © 2019 Elsevier GmbH. All rights reserved.)- Published
- 2019
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27. Phytochemical analysis and anti-inflammatory effects of Filipendula vulgaris Moench extracts.
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Katanić J, Pferschy-Wenzig EM, Mihailović V, Boroja T, Pan SP, Nikles S, Kretschmer N, Rosić G, Selaković D, Joksimović J, and Bauer R
- Subjects
- Animals, Anti-Inflammatory Agents administration & dosage, Cell Line, Cell Line, Tumor, Chromatography, Liquid methods, Cyclooxygenase 1 drug effects, Cyclooxygenase 1 genetics, Cyclooxygenase 1 metabolism, Cyclooxygenase 2 drug effects, Cyclooxygenase 2 genetics, Cyclooxygenase 2 metabolism, Cyclooxygenase Inhibitors pharmacology, Dose-Response Relationship, Drug, Free Radical Scavengers pharmacology, Gene Expression, Humans, Inhibitory Concentration 50, Male, Mass Spectrometry methods, Methanol chemistry, Nitric Oxide metabolism, Phytochemicals pharmacology, Plant Components, Aerial chemistry, Plant Extracts chemistry, Plant Roots chemistry, Rats, Wistar, Anti-Inflammatory Agents pharmacology, Filipendula chemistry, Phytochemicals chemistry, Plant Extracts pharmacology
- Abstract
Filipendula vulgaris Moench (dropwort) is used in traditional medicine for relieving various inflammation-related diseases. In the present study, the phytochemical profile of F. vulgaris aerial part (FVA) and root (FVR) methanolic extracts was evaluated by LC-DAD-HRMS analysis. Furthermore, their in vitro and in vivo anti-inflammatory effects, as well as their potential cytotoxicity, were assessed. Results showed that the extracts mainly contain phenolics like flavonoids, hydrolyzable tannins, procyanidins, and phenolic acid derivatives, including gaultherin. No in vitro cytotoxicity was found at the highest concentration (50 μg/mL). FVA extract (50 μg/mL) significantly inhibited cyclooxygenase-1 and -2 (COX-1 and COX-2) activities in vitro (>50% inhibition), and FVR extract considerably inhibited COX-2 activity (52.5 ± 2.7%) without affecting COX-2 gene expression in LPS-stimulated THP-1 cells. The extracts demonstrated prominent in vivo anti-inflammatory potential upon oral administration in rats. Especially FVA extract at 100 and 200 mg/kg significantly inhibited carrageenan-induced edema formation. From these results, it can be concluded that F. vulgaris extracts possess interesting anti-inflammatory properties., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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28. Periplocin, the most anti-proliferative constituent of Periploca sepium, specifically kills liposarcoma cells by death receptor mediated apoptosis.
- Author
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Lohberger B, Wagner S, Wohlmuther J, Kaltenegger H, Stuendl N, Leithner A, Rinner B, Kunert O, Bauer R, and Kretschmer N
- Subjects
- Cardiac Glycosides, Cell Line, Tumor, China, Digitoxigenin analogs & derivatives, Humans, Plant Extracts pharmacology, Plant Roots chemistry, Plants, Medicinal chemistry, Apoptosis drug effects, Liposarcoma pathology, Periploca chemistry, Receptors, Death Domain metabolism, Saponins pharmacology
- Abstract
Background: During a screening of Chinese plants traditionally used for the treatment of cancer and related diseases, extracts of the root bark of Periploca sepium Bunge showed strong cytotoxic activity., Purpose: Isolate and identify cytotoxic compounds from P. sepium and investigate the effects and mechanism of action on different cancer cell lines., Methods: Extracts obtained with solvents of different polarities of the root bark of P. sepium were tested for their anti-proliferative effects. The most active extract was subjected to activity-guided fractionation using different chromatographic methods. The most active compound was further investigated on sarcoma cell lines regarding its effects concerning apoptosis, DNA damage and death receptor expression., Results: We isolated the cardiac glycosides periplocin, glucosyl divostroside, periplogenin, periplocymarin and periplocoside M with periplocin exhibiting the lowest IC
50 value against leukemia and liposarcoma cells. Liposarcomas are rare tumors within the heterogeneous group of soft tissue sarcomas and respond poorly to conventional treatments. Periplocin led to growth inhibition and apoptosis induction by changing the expression of death receptors and inducing DNA double strand breaks in SW-872 cells., Conclusion: Periplocin displays a promising mechanism of action in sarcoma cells because altering the death receptor expression is an interesting target in sarcoma treatment especially to overcome TRAIL resistance., (Copyright © 2018. Published by Elsevier GmbH.)- Published
- 2018
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29. Synthesis of Jacaranone-Derived Nitrogenous Cyclohexadienones and Their Antiproliferative and Antiprotozoal Activities.
- Author
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Presser A, Lainer G, Kretschmer N, Schuehly W, Saf R, Kaiser M, and Kalt MM
- Subjects
- Antiprotozoal Agents chemistry, Biological Products chemistry, Biological Products pharmacology, Cell Line, Cell Survival, Cyclohexenes chemistry, Humans, Molecular Structure, Parasitic Sensitivity Tests, Phytochemicals chemistry, Phytochemicals pharmacology, Structure-Activity Relationship, Antineoplastic Agents chemical synthesis, Antineoplastic Agents pharmacology, Antiprotozoal Agents chemical synthesis, Antiprotozoal Agents pharmacology, Cyclohexenes chemical synthesis, Cyclohexenes pharmacology
- Abstract
The cytotoxic and antiprotozoal activities of the phytoquinoide, jacaranone, and related compounds have been an ongoing topic in recent drug discovery. Starting from the natural product-derived cyclohexadienone scaffold, a series of nitrogen-containing derivatives were synthesized and subsequently evaluated for their antiproliferative and antiprotozoal activity. Anticancer potency was analyzed using different types of cancer cell lines: MDA-MB-231 breast cancer, CCRF-CEM leukemia, HCT-116 colon cancer, U251 glioblastoma, and, in addition, non-tumorigenic MRC-5 lung fibroblasts. Antiproliferative activities at micromolar concentrations could be shown. Antiprotozoal activity was assessed against Plasmodium falciparum NF54 and Trypanosoma brucei rhodesiense STIB900. For all compounds, selectivity indices (SI) were calculated based on assessed cytotoxicity towards L6 cells. In addition, the structure-activity-relationships and physicochemical parameters of these compounds are discussed.
- Published
- 2018
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30. Synthesis of Novel Shikonin Derivatives and Pharmacological Effects of Cyclopropylacetylshikonin on Melanoma Cells.
- Author
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Durchschein C, Hufner A, Rinner B, Stallinger A, Deutsch A, Lohberger B, Bauer R, and Kretschmer N
- Subjects
- Apoptosis drug effects, Cell Cycle Checkpoints drug effects, Cell Line, Tumor, Cell Membrane drug effects, DNA Breaks, Double-Stranded drug effects, Histones genetics, Humans, Melanoma pathology, Naphthoquinones chemistry, Naphthoquinones pharmacology, Phosphorylation drug effects, Plant Roots chemistry, Skin drug effects, Boraginaceae chemistry, Cell Proliferation drug effects, Melanoma drug therapy, Naphthoquinones chemical synthesis
- Abstract
Despite much research in the last centuries, treatment of malignant melanoma is still challenging because of its mostly unnoticeable metastatic spreading and aggressive growth rate. Therefore, the discovery of novel drug leads is an important goal. In a previous study, we have isolated several shikonin derivatives from the roots of Onosma paniculata Bureau & Franchet (Boraginaceae) which evolved as promising anticancer candidates. β , β -Dimethylacrylshikonin ( 1 ) was the most cytotoxic derivative and exhibited strong tumor growth inhibitory activity, in particular, towards melanoma cells. In this study, we synthesized eighteen novel shikonin derivatives in order to obtain compounds which exhibit a higher cytotoxicity than 1 . We investigated their cytotoxic potential against various melanoma cell lines and juvenile skin fibroblasts. The most active compound was ( R )-1-(1,4-dihydro-5,8-dihydroxy-1,4-dioxonaphthalen-2-yl)-4-methylpent-3-enyl cyclopropylacetate (cyclopropylacetylshikonin) ( 6 ). It revealed significant stronger tumor growth inhibitory activity towards two melanoma cell lines derived from metastatic lesions (WM164 and MUG-Mel2). Further investigations have shown that 6 induced apoptosis caspase-dependently, increased the protein levels of cleaved PARP, and led to double-stranded DNA breaks as shown by phosphorylation of H2AX. Cell membrane damage and cell cycle arrest were not observed.
- Published
- 2018
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31. Comparative Gene Expression Analysis in WM164 Melanoma Cells Revealed That β - β -Dimethylacrylshikonin Leads to ROS Generation, Loss of Mitochondrial Membrane Potential, and Autophagy Induction.
- Author
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Kretschmer N, Deutsch A, Durchschein C, Rinner B, Stallinger A, Higareda-Almaraz JC, Scheideler M, Lohberger B, and Bauer R
- Subjects
- Cell Line, Tumor, Gene Expression Regulation drug effects, Humans, Membrane Potential, Mitochondrial drug effects, Mitochondria drug effects, Naphthoquinones chemistry, Reactive Oxygen Species metabolism, Signal Transduction drug effects, Apoptosis drug effects, Cell Proliferation drug effects, Melanoma drug therapy, Naphthoquinones pharmacology
- Abstract
Skin cancer is currently diagnosed as one in every three cancers. Melanoma, the most aggressive form of skin cancer, is responsible for 79% of skin cancer deaths and the incidence is rising faster than in any other solid tumor type. Previously, we have demonstrated that dimethylacrylshikonin (DMAS), isolated from the roots of Onosma paniculata (Boraginaceae), exhibited the lowest IC
50 values against different tumor types out of several isolated shikonin derivatives. DMAS was especially cytotoxic towards melanoma cells and led to apoptosis and cell cycle arrest. In this study, we performed a comprehensive gene expression study to investigate the mechanism of action in more detail. Gene expression signature was compared to vehicle-treated WM164 control cells after 24 h of DMAS treatment; where 1192 distinct mRNAs could be identified as expressed in all replicates and 89 were at least 2-fold differentially expressed. DMAS favored catabolic processes and led in particular to p62 increase which is involved in cell growth, survival, and autophagy. More in-depth experiments revealed that DMAS led to autophagy, ROS generation, and loss of mitochondrial membrane potential in different melanoma cells. It has been reported that the induction of an autophagic cell death represents a highly effective approach in melanoma therapy.- Published
- 2018
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32. Influence of silibinin and β-β-dimethylacrylshikonin on chordoma cells.
- Author
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Jahanafrooz Z, Stallinger A, Anders I, Kleinegger F, Lohberger B, Durchschein C, Bauer R, Deutsch A, Rinner B, and Kretschmer N
- Subjects
- Apoptosis drug effects, Bone Neoplasms drug therapy, Boraginaceae chemistry, Caspase 3, Cell Line, Tumor, Cell Survival drug effects, Chordoma drug therapy, Humans, Mitochondria drug effects, Plant Roots chemistry, Signal Transduction, Silybin, Antineoplastic Agents, Phytogenic pharmacology, Bone Neoplasms pathology, Chordoma pathology, Naphthoquinones pharmacology, Silymarin pharmacology
- Abstract
Background: Chordoma, slow growing bone tumours originating from remnants of the notochord, leave affected patients with a median survival of six years. The high recurrence rate of chordoma, together with limited treatment options and bad overall prognosis, make the development of new treatment options urgently necessary., Purpose: In this study, the potential of two natural products, silibinin and β-β-dimethylacrylshikonin (DMAS), was tested on clival (MUG-CC1 and UM-Chor1) as well as sacral (MUG-Chor1 and U-CH2) chordoma cell lines. The treatment was administered both as single- and combined therapy., Methods: For investigation of cell viability, the Cell Titer 96 Aqueous Non-Radioactive Cell Proliferation Assay Kit was used. Apoptosis induction was studied by flow cytometry, (Annexin V/SYTOX Green, caspase-3) and RT-qPCR. Pathway analyses were performed by western blot., Results: Both drugs were found to reduce cell viability alone as well as in combination in a dose dependent manner, with DMAS being more efficient than silibinin. The mode of cell death was mainly apoptosis in DMAS treated samples, while the combination therapy led to apoptosis as well as late-apoptosis/necrosis. Silibinin therapy alone, although reducing cell viability, did not lead to significant apoptotic effects in the performed assays. Focussing on the molecular mechanism of DMAS induced apoptosis, it was found that major genes of the mitochondrial apoptosis pathway, like NOXA and PUMA were overexpressed. Additionally, western blot experiments showed a decrease of ERK/pERK, STAT3/pSTAT3 (Tyr705) and AKT/pAKT expression/activation levels under DMAS treatment., Conclusion: DMAS is a promising new candidate for chordoma therapy, while silibinin or a combination of both is less favourable., (Copyright © 2018. Published by Elsevier GmbH.)
- Published
- 2018
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33. Antiproliferative Carvotacetones from Sphaeranthus africanus.
- Author
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Tran HT, Pferschy-Wenzig EM, Kretschmer N, Kunert O, Huynh L, and Bauer R
- Subjects
- Cell Line, Tumor, Drug Screening Assays, Antitumor, HEK293 Cells, Humans, Magnetic Resonance Spectroscopy, Mass Spectrometry, Plant Components, Aerial chemistry, Tetrazolium Salts, Vietnam, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic pharmacology, Asteraceae chemistry, Cyclohexanones chemistry, Cyclohexanones pharmacology
- Abstract
Five carvotacetone derivatives, including two known ones, 3,5-diangeloyloxy-7-hydroxycarvotacetone (1) and 3-angeloyloxy-5-[2″,3″-epoxy-2″-methylbutanoyloxy]-7-hydroxycarvotacetone (2), along with three new compounds, 3-angeloyloxy-5-[3″-chloro-2″-hydroxy-2″-methylbutanoyloxy]-7-hydroxycarvotacetone (3), 5-angeloyloxy-7-hydroxy-3-tigloyloxycarvotacetone (4), and 3-angeloyloxy-5,7-dihydroxycarvotacetone (5), were isolated from the aerial parts of Sphaeranthus africanus collected in Vietnam. Bioassay-guided fractionation was monitored by the antiproliferative activity on CCRF-CEM human cancer cells. The structures of compounds 1-5 were determined on the basis of NMR spectroscopic and mass spectrometric data. Activities of compounds 1-5 were evaluated in vitro against the human cancer cell lines CCRF-CEM, MDA-MB-231, U-251, and HCT-116. All compounds exhibited significant antiproliferative activity against all four cancer cell lines. CCRF-CEM was most sensitive to the compounds, with IC
50 values ranging from 0.6 to 1.5 μM. Compounds 3 and 4 possessed the highest activity, with IC50 values in the four cell lines ranging from 0.6 to 2.9 μM and 1.3 to 2.5 μM, respectively. These compounds also showed inhibitory activity toward the HEK-293 human embryonic kidney cells with IC50 values ranging from 2.5 to 5.5 μM. This is the first time that antiproliferative activity of S. africanus has been reported, and 1-5 are the most cytotoxic carvotacetone derivatives reported so far.- Published
- 2018
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34. Synthesis of new 1-benzyl tetrahydropyridinylidene ammonium salts and their antimicrobial and anticellular activities.
- Author
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Mohsin NU, Seebacher W, Faist J, Hochegger P, Kaiser M, Mäser P, Belaj F, Saf R, Kretschmer N, Alajlani M, Turek I, Brantner A, Bauer R, Bucar F, and Weis R
- Subjects
- Animals, Anti-Bacterial Agents chemical synthesis, Anti-Bacterial Agents chemistry, Antifungal Agents chemical synthesis, Antifungal Agents chemistry, Antineoplastic Agents chemical synthesis, Antineoplastic Agents chemistry, Antiprotozoal Agents chemical synthesis, Antiprotozoal Agents chemistry, Bacteria drug effects, Benzyl Compounds chemical synthesis, Benzyl Compounds chemistry, Cell Line, Tumor, Cell Proliferation drug effects, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Humans, Mice, Microbial Sensitivity Tests, Molecular Structure, Parasitic Sensitivity Tests, Plasmodium falciparum drug effects, Pyridines chemical synthesis, Pyridines chemistry, Quaternary Ammonium Compounds chemical synthesis, Quaternary Ammonium Compounds chemistry, Rats, Saccharomyces cerevisiae drug effects, Salts chemical synthesis, Salts chemistry, Salts pharmacology, Structure-Activity Relationship, Trypanosoma brucei rhodesiense drug effects, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Antineoplastic Agents pharmacology, Antiprotozoal Agents pharmacology, Benzyl Compounds pharmacology, Pyridines pharmacology, Quaternary Ammonium Compounds pharmacology
- Abstract
A series of N-benzyl tetrahydropiperidinylidene pyrrolidinium salts have been synthesized and investigated for their antiplasmodial and antitrypanosomal activities as well as for their cytotoxic effects. The antibacterial, antimycobacterial and anticancer potencies of selected compounds were examined, too. Physicochemical parameters were calculated and structure-activity-relationships are discussed., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)
- Published
- 2018
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35. Anti-tumor effects of shikonin derivatives on human medullary thyroid carcinoma cells.
- Author
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Hasenoehrl C, Schwach G, Ghaffari-Tabrizi-Wizsy N, Fuchs R, Kretschmer N, Bauer R, and Pfragner R
- Abstract
New treatment options are needed for medullary thyroid carcinoma (MTC), a highly metastasizing neuroendocrine tumor that is resistant to standard radiotherapy and chemotherapy. We show that the following shikonin derivatives inhibit cell proliferation and cell viability of the MTC cell line TT: acetylshikonin, β,β-dimethylacrylshikonin, shikonin and a petroleum ether extract of the roots of Onosma paniculata containing several shikonin derivatives. The unsubstituted shikonin derivative was found to be the most effective compound with an IC
50 of 1.1 µM. The cell viability of normal human skin fibroblasts, however, was not affected by the tested substances, indicating that shikonin derivatives might be selectively toxic for cancer cells. We further report that migration and invasion of TT cells were inhibited at non-toxic concentrations. Finally, shikonin was tested in vivo using the chick chorioallantoic membrane assay, where it significantly reduced tumor growth by inhibiting cell proliferation and inducing apoptosis. In summary, our results suggest that shikonin derivatives have the potential for the treatment of medullary thyroid carcinomas., (© 2017 The authors.)- Published
- 2017
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36. Filipendula ulmaria extracts attenuate cisplatin-induced liver and kidney oxidative stress in rats: In vivo investigation and LC-MS analysis.
- Author
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Katanić J, Matić S, Pferschy-Wenzig EM, Kretschmer N, Boroja T, Mihailović V, Stanković V, Stanković N, Mladenović M, Stanić S, Mihailović M, and Bauer R
- Subjects
- Animals, Antineoplastic Agents toxicity, Cell Survival drug effects, Chemical and Drug Induced Liver Injury etiology, Chromatography, Liquid methods, DNA Damage drug effects, Kidney metabolism, Kidney Diseases chemically induced, Liver metabolism, Mass Spectrometry methods, Rats, Rats, Wistar, Chemical and Drug Induced Liver Injury prevention & control, Cisplatin toxicity, Filipendula chemistry, Kidney drug effects, Kidney Diseases prevention & control, Liver drug effects, Oxidative Stress drug effects, Plant Extracts pharmacology
- Abstract
Filipendula ulmaria, known as meadowsweet, is a perennial herb found in wild and cultivated habitats in Europe and Asia. Usage of F. ulmaria in traditional medicine is based on diuretic, astringent, antirheumatic, and anti-inflammatory properties of this plant. Exposure to cisplatin at a dose of 7.5 mg/kg caused significant increase in serum parameters of liver and kidneys function and tissue oxidative stress markers along with some histopathological changes in liver and kidney tissues of experimental rats, as well as high level of genotoxicity. Administration of F. ulmaria extracts in three different concentrations (100, 200, and 400 mg/kg/day) for 10 days resulted in a reduction of oxidative stress in tissues and decrease of serum parameters. Moreover, tested extracts attenuated the genotoxicity of cisplatin in reverse dose-dependent manner. F. ulmaria extracts had no in vitro cytotoxic activity at all applied concentrations (IC
50 > 50 μg/mL). Tested extracts, rich in polyphenolic compounds, attenuate cisplatin-induced liver and kidney oxidative stress, reduce tissue damage, and enhance the antioxidative status of experimental animals during cisplatin application. Therefore, F. ulmaria extracts may be used as supportive agent for the prevention and amelioration of cisplatin side effects., (Copyright © 2016 Elsevier Ltd. All rights reserved.)- Published
- 2017
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37. Influence of harvest season on chemical composition and bioactivity of wild rue plant hydroalcoholic extracts.
- Author
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Pacifico S, Piccolella S, Galasso S, Fiorentino A, Kretschmer N, Pan SP, Bauer R, and Monaco P
- Subjects
- Antineoplastic Agents chemistry, Cell Line, Tumor, Cell Survival, Humans, Phytotherapy, Plant Extracts chemistry, Plant Leaves chemistry, Antineoplastic Agents pharmacology, Plant Extracts pharmacology, Ruta chemistry, Seasons
- Abstract
The rue (Ruta graveolens) copiousness in rural areas of the Campania Region based a thorough chemical and biological investigation aimed at exploring the seasonal variability of phenol constituents in rue leaves and its influence on their antioxidant, cytotoxic and anti-inflammatory capabilities. To this purpose, hydroalcoholic extracts were prepared from plant samples seasonally collected. LC-ESI-MS/MS techniques were employed to analyze qualitatively and quantitatively the seasonal rue phenol content, whereas different chemical antioxidant assays (by DPPH, ABTS, Fe(3+) RP, ORAC, and FCR methods) and XTT redox metabolic activity assay were performed to screen the seasonal phenol complex-related antioxidant and cytotoxic power. The ability of the rue leaf extracts to counteract cyclooxygenase-2 (COX-2) expression was also evaluated. Data obtained highlighted that the adopted extraction procedure markedly pauperized the furanocoumarin content in all the prepared rue extracts. Flavonol glycosides, along with the flavone acacetin and two sinapic acid derivatives were the main constituents of the spring harvest-derived extract, which exerted the highest antioxidant capability in cell-free systems and was capable to inhibit COX-2 synthesis by 44% comparably to dexamethasone, used as positive control. Data provide new insights for developing a proper management of rue plants for new safe industrial purposes in herbal medicine field., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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38. Inhibition of c-MYC with involvement of ERK/JNK/MAPK and AKT pathways as a novel mechanism for shikonin and its derivatives in killing leukemia cells.
- Author
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Zhao Q, Assimopoulou AN, Klauck SM, Damianakos H, Chinou I, Kretschmer N, Rios JL, Papageorgiou VP, Bauer R, and Efferth T
- Subjects
- Cell Line, Tumor, Extracellular Signal-Regulated MAP Kinases metabolism, Humans, JNK Mitogen-Activated Protein Kinases metabolism, Leukemia metabolism, Leukemia pathology, Mitogen-Activated Protein Kinase Kinases metabolism, Proto-Oncogene Proteins c-myc genetics, Signal Transduction, U937 Cells, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Leukemia drug therapy, MAP Kinase Signaling System drug effects, Naphthoquinones pharmacology, Proto-Oncogene Proteins c-akt metabolism, Proto-Oncogene Proteins c-myc metabolism
- Abstract
Leukemia remains life-threatening despite remarkable advances in chemotherapy. The poor prognosis and drug resistance are challenging treatment. Novel drugs are urgently needed. Shikonin, a natural naphthoquinone, has been previously shown by us to be particularly effective towards various leukemia cell lines compared to solid tumors. However, the underlying mechanisms are still poorly understood. Here, we investigated shikonin and 14 derivatives on U937 leukemia cells. Four derivatives (isobutyrylshikonin, 2-methylbutyrylshikonin, isovalerylshikonin and β,β-dimethylacrylshikonin) were more active than shikonin. AnnexinV-PI analysis revealed that shikonins induced apoptosis. Cell cycle G1/S check point regulation and the transcription factor c-MYC, which plays a vital role in cell cycle regulation and proliferation, were identified as the most commonly down-regulated mechanisms upon treatment with shikonins in mRNA microarray hybridizations. Western blotting and DNA-binding assays confirmed the inhibition of c-MYC expression and transcriptional activity by shikonins. Reduction of c-MYC expression was closely associated with deregulated ERK, JNK MAPK and AKT activity, indicating their involvement in shikonin-triggered c-MYC inactivation. Molecular docking studies revealed that shikonin and its derivatives bind to the same DNA-binding domain of c-MYC as the known c-MYC inhibitors 10058-F4 and 10074-G5. This finding indicates that shikonins bind to c-MYC. The effect of shikonin on U937 cells was confirmed in other leukemia cell lines (Jurkat, Molt4, CCRF-CEM, and multidrug-resistant CEM/ADR5000), where shikonin also inhibited c-MYC expression and influenced phosphorylation of AKT, ERK1/2, and SAPK/JNK. In summary, inhibition of c-MYC and related pathways represents a novel mechanism of shikonin and its derivatives to explain their anti-leukemic activity.
- Published
- 2015
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39. Shikonin and its derivatives inhibit the epidermal growth factor receptor signaling and synergistically kill glioblastoma cells in combination with erlotinib.
- Author
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Zhao Q, Kretschmer N, Bauer R, and Efferth T
- Subjects
- Anthraquinones administration & dosage, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Cell Line, Tumor, Drug Synergism, Erlotinib Hydrochloride, Glioblastoma metabolism, Humans, Mitogen-Activated Protein Kinases metabolism, Naphthoquinones administration & dosage, Phosphorylation drug effects, Proto-Oncogene Proteins c-akt metabolism, Quinazolines administration & dosage, Signal Transduction drug effects, ErbB Receptors antagonists & inhibitors, Glioblastoma drug therapy
- Abstract
Overexpression and mutation of the epidermal growth factor receptor (EGFR) gene play a causal role in tumorigenesis and resistance to treatment of glioblastoma (GBM). EGFR inhibitors such as erlotinib are currently used for the treatment of GBM; however, their efficacy has been limited due to drug resistance. New treatment strategies are therefore urgently needed. Shikonin, a natural naphthoquinone, induces both apoptosis and necroptosis in human glioma cells, but the effectiveness of erlotinib-shikonin combination treatment as well as the underlying molecular mechanisms is unknown yet. In this study, we investigated erlotinib in combination with shikonin and 14 shikonin derivatives in parental U87MG and transfected U87MG.ΔEGFR GBM cells. Most of the shikonin derivatives revealed strong cytotoxicity. Shikonin together with five other derivatives, namely deoxyshikonin, isobutyrylshikonin, acetylshikonin, β,β-dimethylacrylshikonin and acetylalkannin showed synergistic cytotoxicity toward U87MG.ΔEGFR in combination with erlotinib. Moreover, the combined cytotoxic effect of shikonin and erlotinib was further confirmed with another three EGFR-expressing cell lines, BS153, A431 and DK-MG. Shikonin not only dose-dependently inhibited EGFR phosphorylation and decreased phosphorylation of EGFR downstream molecules, including AKT, P44/42MAPK and PLCγ1, but also together with erlotinib synergistically inhibited ΔEGFR phosphorylation in U87MG.ΔEGFR cells as determined by Loewe additivity and Bliss independence drug interaction models. These results suggest that the combination of erlotinib with shikonin or its derivatives might be a potential strategy to overcome drug resistance to erlotinib., (© 2015 UICC.)
- Published
- 2015
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40. 25-O-acetyl-23,24-dihydro-cucurbitacin F induces cell cycle G2/M arrest and apoptosis in human soft tissue sarcoma cells.
- Author
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Lohberger B, Kretschmer N, Bernhart E, Rinner B, Stuendl N, Kaltenegger H, Kahl S, Bauer R, and Leithner A
- Subjects
- Apoptosis drug effects, CDC2 Protein Kinase, Caspase 3 metabolism, Cell Line, Tumor, Cell Survival drug effects, Cyclin A genetics, Cyclin B1 genetics, Cyclin B1 metabolism, Cyclin-Dependent Kinase 2 genetics, Cyclin-Dependent Kinase 2 metabolism, Cyclin-Dependent Kinases genetics, Cyclin-Dependent Kinases metabolism, G2 Phase Cell Cycle Checkpoints drug effects, Humans, Inhibitor of Apoptosis Proteins genetics, Inhibitor of Apoptosis Proteins metabolism, Sarcoma, Survivin, Antineoplastic Agents pharmacology, Triterpenes pharmacology
- Abstract
Ethnopharmacological Relevance: Quisqualis indica is used in traditional Chinese medicine to treat cancer and related syndromes and also known for its anthelminthic effects., Aim of the Study: Soft tissue sarcomas represent a rare group of malignant tumors that frequently exhibit chemotherapeutic resistance and increased metastatic potential. In this study, we evaluated the cytotoxic, apoptosis inducing and cell cycle arresting effects of 25-O-acetyl-23,24-dihydro-cucurbitacin F which has been isolated from leaves and twigs of Q. indica., Material and Methods: The present study investigates the effects of 25-O-acetyl-23,24-dihydro-cucurbitacin F (1) on cell viability, cell cycle distribution, and apoptotic induction of three human sarcoma cell lines of various origins by using the CellTiter 96(®) AQueous One Solution Cell Proliferation Assay, flow cytometrical experiments, real-time RT-PCR, Western blotting, and the Caspase-Glo(®) 3/7 Assay, Results: We could show that 1 reduced cell viability in a dose-dependent manner and arrested the cells at the G2/M interface. The accumulation of cells at the G2/M phase resulted in a significant decrease of the cell cycle checkpoint regulators cyclin B1, cyclin A, CDK1, and CDK2. Interestingly, 1 inhibited survivin expression significantly, which functions as a key regulator of mitosis and programmed cell death, and is overexpressed in many tumor types including sarcomas. Moreover, 1 induced apoptosis in liposarcoma and rhabdomyosarcoma cells caspase-3 dependently., Conclusion: Our data strongly support 1 as a very interesting target for further investigation and development of novel therapeutics in sarcoma research., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2015
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41. Influence of seasonal variation on Thymus longicaulis C. Presl chemical composition and its antioxidant and anti-inflammatory properties.
- Author
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Galasso S, Pacifico S, Kretschmer N, Pan SP, Marciano S, Piccolella S, Monaco P, and Bauer R
- Subjects
- Anti-Inflammatory Agents chemistry, Antioxidants chemistry, Molecular Structure, Phenols pharmacology, Anti-Inflammatory Agents isolation & purification, Anti-Inflammatory Agents pharmacology, Antioxidants isolation & purification, Antioxidants pharmacology, Lamiaceae chemistry, Seasons
- Abstract
Thymus longicaulis C. Presl. (Lamiaceae) is a small aromatic perennial herb typical of the Illyric-Mediterranean flora, traditionally used as remedy for cold, flu, cough, nephritis and abdominal pain. In order to carry out a thorough chemical and biological screening of the plant and to explore phenophases influence on its polyphenol content, samples of the plant were collected at different phases during its life cycle (July/October 2012 and January/April 2013). Each sample, previously extracted using a hydroalcoholic solution, was phytochemically analyzed for its metabolic constitution applying LC-DAD-ESI-MS/MS techniques. Although identified metabolites were differently concentrated at the various collection times, T. longicaulis leaf extracts were mainly constituted by low molecular weight phenols, and flavonoids. Rosmarinic acid was found as the main metabolite in Oct12 sample. Chemopreventive efficacy of the investigated extracts, by means of their anti-inflammatory, cytotoxic and antioxidant activities, was assessed. To this purpose, each extract underwent an extensive screening towards five human cell lines: CCRF-CEM (leukemia); U251 (glioblastoma); MDA-MB-231 (breast cancer); HCT-116 (colon cancer) and MRC-5 (lung fibroblasts) through XTT [2,3bis(2-metoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H tetrazolium hydroxide] test. The ability of the extracts to counteract cyclooxygenase-2 (COX-2) expression was also evaluated by COX-2 expression assay in human THP-1 monocyte-derived macrophages. COX-2 inhibition could represent a valuable anticancer strategy as it is associated with carcinogenesis and over-expressed in a variety of human malignancies. Oct12 extract, which was particularly rich in rosmarinic acid and methylapigenin, exhibited a strong antioxidant and anti-inflammatory effectiveness., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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42. Cytotoxic constituents from Lobaria scrobiculata and a comparison of two bioassays for their evaluation.
- Author
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Schinkovitz A, Kaur A, Urban E, Zehl M, Páchniková G, Wang Y, Kretschmer N, Slaninová I, Pauli GF, Franzblau SG, Krupitza G, Bauer R, and Kopp B
- Subjects
- Anti-Bacterial Agents metabolism, Antineoplastic Agents, Phytogenic chemistry, Benzofurans chemistry, Drug Screening Assays, Antitumor, France, HL-60 Cells, Humans, Molecular Structure, Nuclear Magnetic Resonance, Biomolecular, Phenols chemistry, Trypan Blue pharmacology, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Benzofurans pharmacology, Lichens chemistry, Phenols isolation & purification, Phenols pharmacology
- Abstract
Lichens are resilient organisms, known for their unique profiles of secondary metabolites and for exhibiting antioxidative, antibacterial, and cytotoxic effects. Analyzing the cytotoxic potential of Lobaria scrobiculata, a bioassay-guided fractionation strategy yielded seven known metabolites, with two of these compounds, 2 and 3, exhibiting cytotoxicity against HL-60 cells. In order to verify the potential impact of degradation on observed bioactivity, a purity and stability evaluation was conducted. The consistency of results obtained by the water-soluble tetrazolium salt-1 assay and trypan blue cytotoxicity assay was evaluated for selected compounds.
- Published
- 2014
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43. Inhibition of NO production by Grindelia argentina and isolation of three new cytotoxic saponins.
- Author
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Alza NP, Pferschy-Wenzig EM, Ortmann S, Kretschmer N, Kunert O, Rechberger GN, Bauer R, and Murray AP
- Subjects
- Cell Line, Cell Proliferation drug effects, Cell Survival drug effects, Dose-Response Relationship, Drug, Drug Evaluation, Preclinical, Fibroblasts drug effects, Fibroblasts metabolism, Humans, Macrophages drug effects, Macrophages metabolism, Molecular Structure, Saponins chemistry, Saponins isolation & purification, Structure-Activity Relationship, Grindelia chemistry, Nitric Oxide biosynthesis, Saponins pharmacology
- Abstract
A bioassay-guided phytochemical analysis of the ethanolic extract of Grindelia argentina Deble & Oliveira-Deble (Asteraceae) allowed the isolation of a known flavone, hispidulin, and three new oleanane-type saponins, 3-O-β-D-xylopyranosyl-(1→3)-β-D-glucopyranosyl-2β,3β,16α,23-tetrahydroxyolean-12-en-28-oic acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-apiofuranosyl-(1→3)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester (2), 3-O-β-D-glucopyranosyl-2β,3β,23-trihydroxyolean-12-en-28-oic acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-apiofuranosyl-(1→3)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester, (3) and 3-O-β-D-xylopyranosyl-(1→3)-β-D-glucopyranosyl-2β,3β,23-trihydroxyolean-12-en-28-oic acid 28-O-β-D-xylopyranosyl-(1→2)-β-D-apiofuranosyl-(1→3)-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester (4), named grindeliosides A-C, respectively. Their structures were determined by extensive 1D- and 2D-NMR experiments along with mass spectrometry and chemical evidence. The isolated compounds were evaluated for their inhibitory activities against LPS/IFN-γ-induced NO production in RAW 264.7 macrophages and for their cytotoxic activities against the human leukemic cell line CCRF-CEM and MRC-5 lung fibroblasts. Hispidulin markedly reduced LPS/IFN-γ-induced NO production (IC50 51.4 μM), while grindeliosides A-C were found to be cytotoxic, with grindelioside C being the most active against both CCRF-CEM (IC50 4.2±0.1 μM) and MRC-5 (IC50 4.5±0.1 μM) cell lines., (Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.)
- Published
- 2014
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44. Synthesis of tetrahydrohonokiol derivates and their evaluation for cytotoxic activity against CCRF-CEM leukemia, U251 glioblastoma and HCT-116 colon cancer cells.
- Author
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Bernaskova M, Kretschmer N, Schuehly W, Huefner A, Weis R, and Bauer R
- Subjects
- Antineoplastic Agents, Phytogenic pharmacology, Biphenyl Compounds pharmacology, Cell Survival drug effects, Colonic Neoplasms, Drug Screening Assays, Antitumor, Glioblastoma, HCT116 Cells, Humans, Inhibitory Concentration 50, Leukemia, Lignans pharmacology, Methylation, Microwaves, Antineoplastic Agents, Phytogenic chemical synthesis, Biphenyl Compounds chemical synthesis, Lignans chemical synthesis
- Abstract
Biphenyl neolignans such as honokiol and magnolol, which are the major active constituents of the Asian medicinal plant Magnolia officinalis, are known to exert a multitude of pharmacological and biological activities. Among these, cytotoxic and tumor growth inhibitory activity against various tumour cell lines are well-documented. To further elucidate the cytotoxic effects of honokiol derivatives, derivatizations were performed using tetrahydrohonokiol as a scaffold. The derivatizations comprised the introduction of functional groups, e.g., nitro and amino groups, as well as alkylation. This way, 18 derivatives, of which 13 were previously undescribed compounds, were evaluated against CCRF-CEM leukemia cells, U251 glioblastoma and HCT-116 colon cancer cells. The results revealed no significant cytotoxic effects in any of the three tested cell lines at a test concentration of 10 µM.
- Published
- 2014
- Full Text
- View/download PDF
45. How bad was it? Differences in the time course of sensitivity to the magnitude of loss in problem gamblers and controls.
- Author
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Kreussel L, Hewig J, Kretschmer N, Hecht H, Coles MG, and Miltner WH
- Subjects
- Adult, Brain Mapping, Decision Making physiology, Female, Gambling psychology, Humans, Male, Surveys and Questionnaires, Time Factors, Brain physiopathology, Evoked Potentials physiology, Feedback, Psychological physiology, Gambling physiopathology, Reward
- Abstract
Previous research has shown that pathological gamblers show various cognitive distortions, especially in interpreting near losses. Using a modified blackjack task, we investigated the electrophysiological responses to near and full losses in problem gamblers and controls. We assessed the event-related brain potentials (ERPs) of 20 problem gamblers and 21 controls at two time points following negative game outcomes. We also studied the behavioral changes after near and full loss experiences. Between 270 and 320 ms following a loss, controls but not gamblers showed a differential ERP response to near and full losses suggesting that a near loss is evaluated more negatively than a full loss. However, between 430 and 480 ms after a loss, the ERPs of both, gamblers and controls, showed a differential response as a function of the type of loss. Both groups became more cautious in their subsequent gambling behavior following near loss. The present study revealed differences in the time course of processing negative feedback in problem gamblers and normal controls, which might be due to gamblers preoccupation with gains rather than with losses., (Copyright © 2013 Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
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46. Sesquiterpene lactones downregulate G2/M cell cycle regulator proteins and affect the invasive potential of human soft tissue sarcoma cells.
- Author
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Lohberger B, Rinner B, Stuendl N, Kaltenegger H, Steinecker-Frohnwieser B, Bernhart E, Bonyadi Rad E, Weinberg AM, Leithner A, Bauer R, and Kretschmer N
- Subjects
- Cell Line, Tumor, Cell Proliferation drug effects, Cell Survival drug effects, Collagenases genetics, Collagenases metabolism, Cyclin-Dependent Kinase 2 genetics, Cyclin-Dependent Kinase 2 metabolism, Cyclin-Dependent Kinase Inhibitor p27 genetics, Cyclin-Dependent Kinase Inhibitor p27 metabolism, Down-Regulation, Drug Screening Assays, Antitumor, High-Throughput Screening Assays, Humans, Neoplasm Invasiveness, Tumor Suppressor Protein p53 genetics, Tumor Suppressor Protein p53 metabolism, Antineoplastic Agents pharmacology, G2 Phase Cell Cycle Checkpoints drug effects, Gene Expression drug effects, Lactones pharmacology, Sarcoma pathology, Sesquiterpenes pharmacology
- Abstract
Soft tissue sarcomas (STS) represent a rare group of malignant tumors that frequently exhibit chemotherapeutic resistance and increased metastatic potential. Many studies have demonstrated the great potential of plant-derived agents in the treatment of various malignant entities. The present study investigates the effects of the sesquiterpene lactones costunolide and dehydrocostus lactone on cell cycle, MMP expression, and invasive potential of three human STS cell lines of various origins. Both compounds reduced cell proliferation in a time- and dose-dependent manner. Dehydrocostus lactone significantly inhibited cell proliferation, arrested the cells at the G2/M interface and caused a decrease in the expression of the cyclin-dependent kinase CDK2 and the cyclin-dependent kinase inhibitor p27(Kip1). In addition, accumulation of cells at the G2/M phase transition interface resulted in a significant decrease in cdc2 (CDK1) together with cyclin B1. Costunolide had no effect on the cell cycle. Based on the fact that STS tend to form daughter cell nests and metastasize, the expression levels of matrix metalloproteinases (MMPs), which play a crucial role in extracellular matrix degradation and metastasis, were investigated by Luminex® technology and real-time RT-PCR. In the presence of costunolide, MMP-2 and -9 levels were significantly increased in SW-982 and TE-671 cells. Dehydrocostus lactone treatment significantly reduced MMP-2 and -9 expression in TE-671 cells, but increased MMP-9 level in SW-982 cells. In addition, the invasion potential was significantly reduced after treatment with both sesquiterpene lactones as investigated by the HTS FluoroBlock™ insert system.
- Published
- 2013
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47. Antimicrobial and cytotoxic isohexenylnaphthazarins from Arnebia euchroma (Royle) Jonst. (Boraginaceae) callus and cell suspension culture.
- Author
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Damianakos H, Kretschmer N, Sykłowska-Baranek K, Pietrosiuk A, Bauer R, and Chinou I
- Subjects
- Anti-Infective Agents pharmacology, Bacteria drug effects, Cell Culture Techniques, Cell Proliferation drug effects, Humans, Plant Roots chemistry, Boraginaceae chemistry, Naphthoquinones chemistry, Naphthoquinones isolation & purification, Naphthoquinones pharmacology, Plant Extracts chemistry, Plant Extracts pharmacology
- Abstract
The phytochemical investigation of the n-hexane extract from callus and cell suspension culture of Arnebia euchroma (Royle) Jonst. resulted in the isolation of nine isohexenylnaphthazarins: deoxyalkannin (1), alkannin (2), acetylalkannin (3), isobutyrylalkannin (4), β-hydroxyisovalerylalkannin (5), 2''-(S)-α-methylbutyrylalkannin (6), propionylalkannin (7), teracrylalkannin (8) and acetylshikonin (9). Their structures were determined by MS and NMR spectroscopy. Pigments 2–8 are isolated for the first time from Arnebia in vitro cultures, 4 and 7 are reported in the present work as novel metabolites within the Arnebia genus, while 9 is a known constituent of both natural roots and in vitro cultures of A. euchroma. Moreover, methyl jasmonate and 1-monoglyceryl olate, palmitate and stearate are reported for the first time within the Boraginaceae family. The antimicrobial and cytotoxic activities of all isolated pigment compounds were tested, revealing a very interesting profile.
- Published
- 2012
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48. Effect of costunolide and dehydrocostus lactone on cell cycle, apoptosis, and ABC transporter expression in human soft tissue sarcoma cells.
- Author
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Kretschmer N, Rinner B, Stuendl N, Kaltenegger H, Wolf E, Kunert O, Boechzelt H, Leithner A, Bauer R, and Lohberger B
- Subjects
- ATP Binding Cassette Transporter, Subfamily B, ATP Binding Cassette Transporter, Subfamily B, Member 1 genetics, ATP Binding Cassette Transporter, Subfamily B, Member 1 metabolism, ATP Binding Cassette Transporter, Subfamily G, Member 2, ATP-Binding Cassette Transporters genetics, ATP-Binding Cassette Transporters metabolism, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Blotting, Western, Caspase 3 metabolism, Caspase 7 metabolism, Cell Proliferation drug effects, Cell Survival, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Enzyme Activation drug effects, Gene Expression Regulation, Neoplastic, Humans, Inhibitory Concentration 50, Lactones chemistry, Lactones isolation & purification, Multidrug Resistance-Associated Proteins genetics, Multidrug Resistance-Associated Proteins metabolism, Neoplasm Proteins genetics, Neoplasm Proteins metabolism, Proteolysis, Real-Time Polymerase Chain Reaction, Sarcoma genetics, Saussurea chemistry, Sesquiterpenes chemistry, Sesquiterpenes isolation & purification, Time Factors, Apoptosis drug effects, Cell Cycle drug effects, Lactones pharmacology, Sarcoma pathology, Sesquiterpenes pharmacology
- Abstract
Human soft tissue sarcomas represent a rare group of malignant tumours that frequently exhibit chemotherapeutic resistance and increased metastatic potential following unsuccessful treatment. In this study, we investigated the effects of costunolide and dehydrocostus lactone, which have been isolated from Saussurea lappa using activity-guided isolation, on three soft tissue sarcoma cell lines of various origins. The effects on cell proliferation, cell cycle distribution, apoptosis induction, and ABC transporter expression were analysed. Both compounds inhibited cell viability dose- and time-dependently. IC50 values ranged from 6.2 µg/mL to 9.8 µg/mL. Cells treated with costunolide showed no changes in cell cycle, little in caspase 3/7 activity, and low levels of cleaved caspase-3 after 24 and 48 h. Dehydrocostus lactone caused a significant reduction of cells in the G1 phase and an increase of cells in the S and G2/M phase. Moreover, it led to enhanced caspase 3/7 activity, cleaved caspase-3, and cleaved PARP indicating apoptosis induction. In addition, the influence of costunolide and dehydrocostus lactone on the expression of ATP binding cassette transporters related to multidrug resistance (ABCB1/MDR1, ABCC1/MRP1, and ABCG2/BCRP1) was examined using real-time RT-PCR. The expressions of ABCB1/MDR1 and ABCG2/BCRP1 in liposarcoma and synovial sarcoma cells were significantly downregulated by dehydrocostus lactone. Our data demonstrate for the first time that dehydrocostus lactone affects cell viability, cell cycle distribution and ABC transporter expression in soft tissue sarcoma cell lines. Furthermore, it led to caspase 3/7 activity as well as caspase-3 and PARP cleavage, which are indicators of apoptosis. Therefore, this compound may be a promising lead candidate for the development of therapeutic agents against drug-resistant tumours., (Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2012
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49. Application of water quality indices and analysis of the surface water quality monitoring network in semiarid North-Central Chile.
- Author
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Espejo L, Kretschmer N, Oyarzún J, Meza F, Núñez J, Maturana H, Soto G, Oyarzo P, Garrido M, Suckel F, Amezaga J, and Oyarzún R
- Subjects
- Agricultural Irrigation, Chile, Climate, Cluster Analysis, Environmental Monitoring legislation & jurisprudence, Environmental Monitoring methods, Environmental Monitoring statistics & numerical data, Metals, Heavy analysis, Water Pollution, Chemical statistics & numerical data, Water Pollutants, Chemical analysis, Water Quality standards
- Abstract
Surface water quality has increasing importance worldwide and is particularly relevant in the semiarid North-Central Chile, where agriculture and mining activities are imposing heavy pressure on limited water resources. The current study presents the application of a water quality index in four watersheds of the 29°-33°S realm for the period 1999-2008, based on the Canadian Council of Ministers for the Environment approach and the Chilean regulation for irrigation water quality. In addition, two modifications to the index are tested and a comprehensive characterization of the existing monitoring network is performed through cluster analysis. The basins studied show fairly good water quality in the overall, specially the Limarí basin. On the other hand, the lower index values were obtained for the headwaters of Elqui, associated with the El Indio mining district. The first modification of the indicator (i.e., to consider parameters differentially according to their effect on human health or the environment) did not produce major differences with respect to the original index, given the generally good water quality. The second modification (i.e., to consider as threshold values the more restrictive figures derived from a set of regulations) yielded important differences in the indicator values. Finally, an adequate characterization of the monitoring network was obtained. The results presented spatial coherence and the information can be used as a basis for the optimization of the monitoring network if required.
- Published
- 2012
- Full Text
- View/download PDF
50. Naphthoquinones from Onosma paniculata induce cell-cycle arrest and apoptosis in melanoma Cells.
- Author
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Kretschmer N, Rinner B, Deutsch AJ, Lohberger B, Knausz H, Kunert O, Blunder M, Boechzelt H, Schaider H, and Bauer R
- Subjects
- Antineoplastic Agents, Phytogenic chemistry, Apoptosis drug effects, Caspase 3 drug effects, Caspase 3 metabolism, Caspase 7 drug effects, Caspase 7 metabolism, Drug Screening Assays, Antitumor, Drugs, Chinese Herbal chemistry, Humans, Melanoma, Molecular Structure, Naphthoquinones chemistry, Plant Roots chemistry, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Boraginaceae chemistry, Cell Cycle drug effects, Drugs, Chinese Herbal isolation & purification, Drugs, Chinese Herbal pharmacology, Naphthoquinones isolation & purification, Naphthoquinones pharmacology
- Abstract
Activity-guided fractionation of a petroleum ether-soluble extract of the roots of Onosma paniculata, which has been shown to affect the cell cycle and to induce apoptosis in melanoma cells, led to the isolation of several shikonin derivatives, namely, β-hydroxyisovalerylshikonin (1), acetylshikonin (2), dimethylacrylshikonin (3), and a mixture of α-methylbutyrylshikonin and isovalerylshikonin (4+5). All compounds exhibited strong cytotoxicity against eight cancer cell lines and MRC-5 lung fibroblasts, with 3 found to possess the most potent cytotoxicity toward four melanoma cell lines (SBcl2, WM35, WM9, and WM164). Furthermore, 3 and the mixture of 4+5 were found to interfere with cell-cycle progression in these cell lines and led to an increasing number of cells in the subG1 region as well as to caspase-3/7 activation, indicating apoptotic cell death.
- Published
- 2012
- Full Text
- View/download PDF
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