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The effect of indole alkaloids on selected cell lines and DNA structures
Dobrovolná, Michaela ; Hoová, Julie (referee) ; Brázda, Václav (advisor)
G-quadruplexes (G4) are secondary DNA structures formed by a cluster of guanines that have been shown to play a role in many biological functions, including regulation of replication timing and repression of oncogene expression. In this work, four plant alkaloids (harmine, harmane, harmaline, and brucine) were tested as potential G4 ligands that could regulate, induce, or convert different G4 topologies. Furthermore, their effect on fibroblast cell line HDF164 and breast cancer cell line MCF-7 was studied, in which case a dose-dependent growth inhibition mechanism was demonstrated. Interaction with the parallel G4 promoter of the proto-oncogene c-Myc was confirmed for harmine, harmaline, and brucine, and with the hybrid G4 of telomeric DNA for harmine, harman, and harmaline. In addition, the ability of the tested compounds to interact with calf thymus double-stranded DNA (ctDNA) was verified by UV-Vis absorption spectroscopy. The methylation assay showed that the DNA of MCF-7 cells treated with harmine and brucine was hypermethylated.
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Alkaloids from Vinca minor L. and their biological activity.
Vrabec, Rudolf ; Opletal, Lubomír (advisor) ; Kokoška, Ladislav (referee) ; Lapčík, Oldřich (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Candidate: Mgr. Rudolf Vrabec Supervisor: prof. RNDr. Lubomír Opletal, CSc. Title of doctoral thesis: Alkaloids from Vinca minor L. and their biological activity Key words: Vinca, indole alkaloids, Alzheimer's disease, AChE, BuChE, POP, GSK-3β, cytotoxicity, docking study Twenty-three monoterpene indole alkaloids of different structural types were isolated by chromatographic techniques from aerial parts of Vinca minor L. (Apocynaceae). The alkaloids were identified by a combination of analytical methods (NMR, MS, HRMS, optical rotation). Among obtained compounds, one structure was undescribed so far and was named vincaminorudeine. Eleven alkaloids were isolated for the first time from this species. Obtained compounds that were isolated in sufficient amounts were subjected to in vitro tests for the inhibition of hAChE, hBuChE, POP, and GSK-3β - enzymes that play a key role in the pathophysiology of Alzheimer's disease. The most active alkaloid was (−)-2-ethyl-3[2-(3-ethylpiperidinyl)-ethyl]-1H- indole (VR-19) with IC50 = 0,65 µM for the inhibition of hBuChE, and with IC50 = 58 µM for the inhibition of POP. Other alkaloids which exhibited a significant inhibition against hBuChE (IC50 30...
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Alkaloids from Vinca minor L. and their biological activity.
Vrabec, Rudolf ; Opletal, Lubomír (advisor) ; Kokoška, Ladislav (referee) ; Lapčík, Oldřich (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Candidate: Mgr. Rudolf Vrabec Supervisor: prof. RNDr. Lubomír Opletal, CSc. Title of doctoral thesis: Alkaloids from Vinca minor L. and their biological activity Key words: Vinca, indole alkaloids, Alzheimer's disease, AChE, BuChE, POP, GSK-3β, cytotoxicity, docking study Twenty-three monoterpene indole alkaloids of different structural types were isolated by chromatographic techniques from aerial parts of Vinca minor L. (Apocynaceae). The alkaloids were identified by a combination of analytical methods (NMR, MS, HRMS, optical rotation). Among obtained compounds, one structure was undescribed so far and was named vincaminorudeine. Eleven alkaloids were isolated for the first time from this species. Obtained compounds that were isolated in sufficient amounts were subjected to in vitro tests for the inhibition of hAChE, hBuChE, POP, and GSK-3β - enzymes that play a key role in the pathophysiology of Alzheimer's disease. The most active alkaloid was (−)-2-ethyl-3[2-(3-ethylpiperidinyl)-ethyl]-1H- indole (VR-19) with IC50 = 0,65 µM for the inhibition of hBuChE, and with IC50 = 58 µM for the inhibition of POP. Other alkaloids which exhibited a significant inhibition against hBuChE (IC50 30...
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Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus
Faschingbauer, Jakub ; Chlebek, Jakub (advisor) ; Šafratová, Marcela (referee)
Faschingbauer J.: Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019. During the screening of biologically active secondary metabolites of plants carried out at the Department of Pharmaceutical Botany FAF UK, selected taxa of the genus Centaurea (Asteraceae) were investigated. This study is focused on a basic phytohemical research of extracts prepared from Centaurea cyanus, Centaurea jacea, Centaurea scabiosa, Centaurea pseudophrygia, Centuarea stoebe, Centaurea solstitialis a Centaurea benedicta. Extracts were prepared for evidence of the proof reactions of TLC and MS analysis (EI, ESI) to clarify a potential presence of alkaloids. EtOAc and ethanol extracts were evaluated for potential inhibitory activity against human erythrocyte acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) and cytotoxicity against selected 9 tumor lines. C. cyanus alkaloid extract had interesting cholinesterase activity which selectively inhibited BChE (IC50 BChE = 22.62 ± 3.62 μg / ml, IC50 AChE = 221.50 ± 44.56 g / ml). Other EtOAc extracts of selected Centaurea species were considered inactive (IC50 > 100 μg/ml)....
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Vinca minor L. alkaloids and their biological activity VIII.
Hojgrová, Veronika ; Chlebek, Jakub (advisor) ; Šafratová, Marcela (referee)
V. Hojgrová: Alkaloids of Vinca minor L. and their biological activity VIII. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany. Number of pages 69. This diploma thesis deals with the isolation of alkaloids from Vinca minor L. from the family Apocynaceae. Separation of alkaloids from the selected fraction (VM 215-258) or from their subfractions (VM 34-41, VM 86, VM 87-113) was performed by preparative TLC. Two pure alkaloids were isolated from the subfraction (VH 34-41). The first VH-1 alkaloid not yet isolated and the second VH 2 alkaloid: (-)-raucubainin. Alkaloids were identified by EI-MS, LC-MS, NMR and optical rotation and were compared with data in the literature. Isolated alkaloids were tested for acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and prolyloligopeptidase (POP) inhibitory activity and for cytotoxicity. Both substances did not show significant cholinesterase inhibitory activity IC50 against AChE after measurement, only (-)-raucubainin showed a slight activity against BuChE (IC50 = 94 ± 7 μM), VH-1 was found to be inactive (IC50 > 100 μM). POP inhibitory activity has so far only been tested for (-)-raucubainin; was found to be inactive (IC50 > 1000 µM). The results of the cytotoxic activity of the alkaloids...
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Vinca minor L. alkaloids and their biological activity II.
Pavuková, Simona ; Chlebek, Jakub (advisor) ; Hradiská Breiterová, Kateřina (referee)
Pavuková, S.:Vinca minor L. alkaloids and their biological activity II. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové 2020. Vinca minor L. is a species of species of flowering plant, native mainly to central and southern Europe, which containst more than 50 indole alkaloids. During screening of potential plant inhibitors against human acetylcholinesterase (hAChE) and butyrylcholinesterase (HBChE) at our department, an alkaloidal extract from dried aerial parts of Vinca minor demonstrated strong and selective hBChE inhibitory activity with an IC50 value of 13.60 ± 0.83 μg/mL, however, against hAChE was inactive (IC50 value >100 μg/mL). The fraction VM 323 - 327 (4,72 g) was separated by column chromatography on silica gel again with stepwise elution by using chloroform and ethanol and overall 7 joined fractions were obtained.Subsequently, repeated preparative TLC on silica gel led to isolation of three compounds; the newly isolated substance SP-1, (-)-picrinine (SP-2) and deacetylakuammiline (SP-3). Their structures were elucidated with mass spectrometry (ESI), NMR and optical rotation. Isolated alkaloids were tested on ability to inhibit AChE, BuChE, POP a GSK-3β, which are enzymes playing an important role in...
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Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus II.
Miklová, Veronika ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
Miklová V.: Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus II. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2020. This Diploma Thesis was carried out at the Department of Pharmaceutical Botany FAF UK and it is a part of a screening of biologically active secondary metabolites of selected on taxa of the genera Centaurea L. and Psephellus L. in the family Asteraceae. Secondary metabolites are responsible for various effects on the human body. The study is focused on the phytochemical research of extracts prepared from aerial parts (cauloms with leaves) of Centaurea cyanus L., Centaurea stoebe L., Cyanus montanus (L.) Hill, Centaurea benedicta L., Centaurea jacea L., Centaurea macrocephala Muss. Puschk. ex. Willd, Centaurea solstitialis L., Centaurea nigra L., Centaurea scabiosa L., Psephellus bellus (Trautv.) Wagenitz, Centaurea pannonica (Heuff.) Hayek and Psephellus dealbatus (Willd) K. Koch. Both ethyl acetate and summary ethanolic extracts were prepared for detection of individual groups of secondary metabolites by thin-layer chromatohraphy. Consistently with previously published results, sesquiterpenes, flavonoids, coumarins, phenolic compounds,...
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Vinca minor L. alkaloids and their biological activity I.
Jurkaninová, Martina ; Chlebek, Jakub (advisor) ; Opletal, Lubomír (referee)
1 9 ABSTRACT Jurkaninová, M.: Vinca minor L. alkaloids and their biological activity I. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019 The aim of this thesis was the isolation of alkaloids from selected fraction 3 (joined fractions (15 - 36), which was a sub-fraction of the fraction VM 323 - 327. It was obtained from the previous processing of an alkaloidal extract from the Vinca minor L at the Department of Pharmaceutical Botany as a part of elaboration of diploma thesis of Aneta Vítavcová.[78] The fraction VM 323-327 was separated by column chromatography on silica gel and a totally, of 7 subfractions were obtained. Subsequent repeated processing of the selected sub-fraction 3 (15 - 36) by preparative TLC on silica gel resulted in the isolation of (-)-vinoxine and its racemate (±)-vinoxine. Identification of their structure was determined based on MS, NMR and optical rotation. The inhibitory activity against acetylcholinesterase, butyrylcholiesterase and prolyl oligopeptidase were determined for the isolated substances. Inhibitory activity against selected enzymes was measured by spectrophotometric methods. Isolated alkaloids were required to be inactive against AChE and POP (IC50 >1000 μM), against to BChE showed a...
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Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus
Faschingbauer, Jakub ; Chlebek, Jakub (advisor) ; Šafratová, Marcela (referee)
Faschingbauer J.: Cytotoxic and cholinesterase inhibitory activity of extracts from selected species of the Centaurea L. genus. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany, Hradec Králové, 2019. During the screening of biologically active secondary metabolites of plants carried out at the Department of Pharmaceutical Botany FAF UK, selected taxa of the genus Centaurea (Asteraceae) were investigated. This study is focused on a basic phytohemical research of extracts prepared from Centaurea cyanus, Centaurea jacea, Centaurea scabiosa, Centaurea pseudophrygia, Centuarea stoebe, Centaurea solstitialis a Centaurea benedicta. Extracts were prepared for evidence of the proof reactions of TLC and MS analysis (EI, ESI) to clarify a potential presence of alkaloids. EtOAc and ethanol extracts were evaluated for potential inhibitory activity against human erythrocyte acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) and cytotoxicity against selected 9 tumor lines. C. cyanus alkaloid extract had interesting cholinesterase activity which selectively inhibited BChE (IC50 BChE = 22.62 ± 3.62 μg / ml, IC50 AChE = 221.50 ± 44.56 g / ml). Other EtOAc extracts of selected Centaurea species were considered inactive (IC50 > 100 μg/ml)....
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