|
|
Amaryllidaceae alkaloids of haemanthamine structural type and their semisynthetic derivatives as potential drugs in the treatment of Alzheimer's disease.
Peřinová, Rozálie ; Cahlíková, Lucie (advisor) ; Lapčík, Oldřich (referee) ; Mučaji, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Candidate: Ing. Rozálie Peřinová Supervisor: prof. Ing. Lucie Cahlíková, Ph.D. Title of doctoral thesis: Amaryllidaceae alkaloids of haemanthamine structural type and their semisynthetic derivatives as potential drugs in the treatment of Alzheimer's disease. To deepen the knowledge about the Amaryllidaceae alkaloid haemanthamine, which was isolated at our workplace as part of previous phytochemical studies, derivatives of this alkaloid were synthesized. First, series of aliphatic (3-12) and aromatic ester derivatives (13-66) were prepared, and then, to compare the structure-activity relationship, ether derivatives (67-80) were prepared from the most active substituents. All synthesized compounds were identified using the following structural analysis methods: NMR, HPLC/MS, and HRMS, including testing physical properties such as optical rotatability. After structure confirmation, all derivatives were subjected to screening studies for their inhibitory potential against hAChE and hBuChE. The selected derivatives were tested for their inhibitory potential against another enzyme, GSK-3β, which plays a significant role in the pathogenesis of AD. In cooperation with the Faculty of Medicine in...
|
|
|
New insulin-like growth factor 1 (IGF-1) analogs for receptor studies and therapeutic applications
Lin, Jingjing ; Jiráček, Jiří (advisor) ; Hodek, Petr (referee) ; Lapčík, Oldřich (referee)
The insulin/IGF system is an evolutionary conserved network that includes three closely related peptide hormones (insulin, IGF-1 and IGF-2), three homologous tyrosine kinase receptors (IR-A, IR-B and IGF-1R), a distinct IGF-2 receptor (IGF-2R), and six IGF-binding proteins. While insulin signals mainly via IR, playing a key role in glucose homeostasis, IGFs mainly signal via IGF-1R to mediate normal human growth. A tight control of ligands and receptors expression is crucial for the proper functioning of the organism. Aberrant signaling by these receptors is manifested in many pathological conditions, including cancer, growth disorders, neurodegenerative diseases and diabetes. Hence, the insulin/IGF axis represents a promising therapeutic target. In view of the multiple unsuccessful clinical anticancer trials performed either with tyrosine kinase inhibitors or antibodies targeted against IGF-1R, the development of novel selective and receptor-specific insulin and IGF analogs with minimized side effects would be of interest. Our study began with the recombinant preparation of IGF-1 dimers in which IGF-1 monomers are interlinked between their C- and N-termini with Ser-Gly linkers (length of 8, 15 or 25 residues). The goal was to investigate whether the binding of two covalently linked IGF-1 molecules...
|
|
|
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...
|
|
|
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...
|
|
|
Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence
Breiterová, Kateřina ; Cahlíková, Lucie (advisor) ; Nagy, Milan (referee) ; Lapčík, Oldřich (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Mgr. Kateřina Breiterová Supervisor: Assoc. prof. Ing. Lucie Cahlíková PhD. Title of Doctoral Thesis: Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence Key words: alkaloids, Amaryllidaceae, analogues, AChE, BuChE, POP, GSK-3β, cell cycle progression, apoptosis Narcissus cv. Professor Einstein was chosen based on results of previous screening studies for detailed phytochemical work for the purpose of isolation of the widest range of AmA. From 34,3 kg of fresh bulbs was obtained 31,7 g of purified alkaloidal extract, which was processed using column chromatography with stepwise elution by light petrol, chloroform and ethanol in different ratios to almost 500 fractions. These fractions were fused into 27 subfractions, which were processed by preparative TLC, vacuum column chromatography and crystallization. Finally, 25 pure alkaloids were isolated. All compounds were identified by GC-MS, ESI-MS, NMR, optical rotation and literature. One compound was identified as a new unpublished alkaloid of lycorine structure type. All alkaloids isolated in sufficient amount were tested for their biological activities associated with Alzheimer's disease (inhibition of...
|
|
|
Alkaloids of Zephyranthes citrina (Amaryllidaceae): isolation, identification, biological activity.
Kohelová, Eliška ; Cahlíková, Lucie (advisor) ; Lapčík, Oldřich (referee) ; Mučaji, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Mgr. Eliška Kohelová Supervisor: prof. Ing. Lucie Cahlíková, Ph.D. Title of Doctoral Thesis: Alkaloids of Zephyranthes citrina (Amaryllidaceae): isolation, structure identification, biological activity. Key words: Amaryllidaceae alkaloids, Zephyranthes, Alzheimer's disease, AChE, BuChE, POP, oncological diseases Zephyranthes citrina Baker was chosen, based on result of previous screening study and literatury research, for detailed phytochemical work for the purpose of isolation of the widest range of AAs. From 35 kg of fresh bulbs was obtained 151 g of purified alkaloidal extract, which was processed using column chromatography to almost 700 fractions. These fractions were connected into 27 subfractions, which were processed by liquid-liquid extraction, flash chromatography, preparative TLC and crystallization. Finally, 27 pure alkaloids were isolated. All compounds were identified by MS (EI, ESI), HRMS, 1D- and 2D-NMR, CD, optical rotation and by comparison with literature data. Seven compounds were identified as new undescribed alkaloids (6α-ethoxyhippeastidine, 10-deoxy-6α-ethoxyhippeastidine, narcieliine, zephyjanine, zephycitrine I, 7-ethoxy-10-methoxy-1-methyllycorenane-9-ol a zephycitrin...
|
|
|
The Impact of Selected Endocrine Disruptors on Human Spermatogenesis
Vítků, Jana ; Hill, Martin (advisor) ; Pohanka, Michal (referee) ; Lapčík, Oldřich (referee)
Steroid hormones in testis play an important role in spermatogenesis, maintenance of the male reproductive tract, production of semen and the maintenance of secondary sex characteristics and libido. They are also discussed as a target for substances called endocrine disruptors (EDs). No complex study was conducted on evaluation of relationships between EDs and steroid spectrum in 2 biological fluids; seminal plasma and plasma. The aim of the PhD. thesis was to develop and validate a method for determination of bisphenol A (BPA) and steroid spectrum in plasma and seminal plasma and to shed more light into mechanisms of ED action and effects of BPA and polychlorinated biphenyls (PCBs) on human spermatogenesis and steroidogenesis. Two new liquid-chromatography mass spectrometry methods for determination of BPA and 11 steroids in plasma and seminal plasma were developed and validated. The methods were used for estimation of analyte concentrations in 191 men with a different degree of fertility. Concurrently, the levels of six congeners of PCBs, gonadotropins, selenium and zinc in plasma were estimated. Partial correlations adjusted for age and BMI were calculated to evaluate relationships between these analytes. Seminal BPA, but not plasma BPA, was negatively associated with sperm concentration...
|
|
|
Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence
Breiterová, Kateřina ; Cahlíková, Lucie (advisor) ; Nagy, Milan (referee) ; Lapčík, Oldřich (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Mgr. Kateřina Breiterová Supervisor: Assoc. prof. Ing. Lucie Cahlíková PhD. Title of Doctoral Thesis: Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence Key words: alkaloids, Amaryllidaceae, analogues, AChE, BuChE, POP, GSK-3β, cell cycle progression, apoptosis Narcissus cv. Professor Einstein was chosen based on results of previous screening studies for detailed phytochemical work for the purpose of isolation of the widest range of AmA. From 34,3 kg of fresh bulbs was obtained 31,7 g of purified alkaloidal extract, which was processed using column chromatography with stepwise elution by light petrol, chloroform and ethanol in different ratios to almost 500 fractions. These fractions were fused into 27 subfractions, which were processed by preparative TLC, vacuum column chromatography and crystallization. Finally, 25 pure alkaloids were isolated. All compounds were identified by GC-MS, ESI-MS, NMR, optical rotation and literature. One compound was identified as a new unpublished alkaloid of lycorine structure type. All alkaloids isolated in sufficient amount were tested for their biological activities associated with Alzheimer's disease (inhibition of...
|
|
|
Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence
Breiterová, Kateřina ; Cahlíková, Lucie (advisor) ; Lapčík, Oldřich (referee) ; Nagy, Milan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Mgr. Kateřina Breiterová Supervisor: Assoc. prof. Ing. Lucie Cahlíková PhD. Title of Doctoral Thesis: Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence Key words: alkaloids, Amaryllidaceae, analogues, AChE, BuChE, POP, GSK-3β, cell cycle progression, apoptosis Narcissus cv. Professor Einstein was chosen based on results of previous screening studies for detailed phytochemical work for the purpose of isolation of the widest range of AmA. From 34,3 kg of fresh bulbs was obtained 31,7 g of purified alkaloidal extract, which was processed using column chromatography with stepwise elution by light petrol, chloroform and ethanol in different ratios to almost 500 fractions. These fractions were fused into 27 subfractions, which were processed by preparative TLC, vacuum column chromatography and crystallization. Finally, 25 pure alkaloids were isolated. All compounds were identified by GC-MS, ESI-MS, NMR, optical rotation and literature. One compound was identified as a new unpublished alkaloid of lycorine structure type. All alkaloids isolated in sufficient amount were tested for their biological activities associated with Alzheimer's disease (inhibition of...
|
|
|
Sulfation and desulfation of neuroactive steroids in normal and neoplastic primate brain tissues
Kříž, Lubomír ; Hampl, Richard (advisor) ; Lapčík, Oldřich (referee) ; Pácha, Jiří (referee)
A novel methodology for the determination of steroid sulfatase (STS) and sulfotransferase (SULT) activities in primate brain tissue have been developed and evaluated. STS activity determination was based on enzyme assay followed by liquid-liquid extraction ofthe reaction product, its subsequent derivatization and gas chromatography-mass spectrometry analysis. Indirect determination including product hydrolysis and determination by radioimmunoassay was used for assessment of SULT activity. For both, STS and SULT assays, optimal reaction conditions were found while strong structure-activity relationships for both enzyme activities were observed. Additionally, so far unidentified high-substrate inhibition for STS was revealed wíth a hypothesis suggesting its physiotogícal relevance' Determinations of STS and SULT activities in monkey brain regions revealed differences between genders and brain regions. Due to low number of samples, significance was not described. For STS kinetic characteristics were determined. In human brain tumors, STS and SULT activities showed highly significant differences according to diagnoses. Furthermore, tendency to cluster formation with respect to both enzyme activities emerged. It indicated specific metabolic characteristics especially for glioblastomas considered as the...
|
guest ::
