Search

Your search keyword '"Klupczynska, Agnieszka"' showing total 30 results
Start Over Author "Klupczynska, Agnieszka"
30 results on '"Klupczynska, Agnieszka"'

20. Overexpression of Prolidase Induces Autophagic Death in MCF-7 Breast Cancer Cells.

Author

Zareba, Ilona, Huynh, Thi Yen Ly, Kazberuk, Adam, Teul, Joanna, Klupczynska, Agnieszka, Matysiak, Jan, Surazynski, Arkadiusz, and Palka, Jerzy

Subjects
GENE expression, BREAST cancer, CANCER cells, AUTOPHAGY, CELL survival
Abstract

Background/Aims: Proline availability for proline dehydrogenase/proline oxidase (PRODH/POX) may represent switching mechanism between PRODH/POX-dependent apoptosis and autophagy. The aim of the study was to evaluate the impact of overexpression of prolidase (proline releasing enzyme) on apoptosis/autophagy in breast cancer MCF-7 cells. Methods: The model of MCF-7 cells with prolidase overexpression (MCF-7PL) was obtained. In order to targeting proline for PRODH/POX-dependent pathways substrate for prolidase, glycyl-proline (GP) was provided and proline utilization for collagen biosynthesis was blocked using 2-methoxyestradiol (MOE). Cell viability was determined using Nucleo-Counter NC-3000. The activity of prolidase was determined by colorimetric assay. DNA, collagen and total protein biosynthesis were determined by radiometric method. Expression of proteins was assessed by Western blot and immunofluorescence bioimaging. Concentration of proline was analyzed by liquid chromatography with mass spectrometry. Results: Prolidase overexpression in MCF-7PL cells contributed to 10-fold increase in the enzyme activity, 3-fold increase in cytoplasmic proline level and decrease in cell viability and DNA biosynthesis compared to wild type MCF- 7 cells. In MCF-7PL cells MOE and GP significantly decreased the number of living cells. MOE inhibited DNA biosynthesis in both cell lines while GP evoked inhibitory effect on the process only in MCF-7PL cells. In both cell lines, MOE or MOE+GP inhibited DNA and collagen biosynthesis. Although GP in MCF-7 cells stimulated collagen biosynthesis, it inhibited the process in MCF-7PL cells. The effects of studied compounds in MCF-7PL cells were accompanied by increase in the expression of Atg7, LC3A/B, Beclin-1, HIF-1α and decrease in the expression of PRODH/POX, active caspases-3 and -9. Conclusion: The data suggest that overexpression of prolidase in MCF-7 cells contributes to increase in intracellular proline concentration and PRODH/POX-dependent autophagic cell death. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

30. Extending Metabolomic Studies of Apis mellifera Venom: LC-MS-Based Targeted Analysis of Organic Acids.

Author

Pawlak, Magdalena, Klupczynska, Agnieszka, Kokot, Zenon J, and Matysiak, Jan

Subjects
*ORGANIC acids, *LIQUID chromatography-mass spectrometry, *HONEYBEES, *ACID analysis, *GLUTARIC acid, *MALONIC acid, *FUMARATES
Abstract

Organic acids are important active small molecules present in venoms and toxins, which have not been fully explored yet. The aim of the study was the determination of organic acids in honeybee venom (HBV) samples by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two protocols for sample preparation were employed. A solid-phase extraction was used for the determination of malonic acid, fumaric acid, glutaric acid, and kynurenic acid. A dilute-and-shoot method was optimal for: citric acid, malic acid, and succinic acid. Chromatographic separation was performed using a Synergi Hydro-RP column. Detection was performed on a triple-quadrupole mass spectrometer operating in multiple reaction monitoring mode. Among the analytes, glutaric acid and kynurenic acid were present in HBV samples in the lowest concentrations, whereas citric acid was the most abundant acid in each sample, and accounted for an average of 86 mg/g (8.6%) of the venom dry weight. Organic acids were discussed in terms of function. This is the first study in the available literature that provides specific data on the content of organic acids in HBV using a validated quantitative method. [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results