Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Monika Moravcová Supervisor: Assoc. Prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of thesis: Preparation of a Novel Method for Screening of Cobalt Chelators Cobalt as a structural part of the vitamin B12 is an essential microelement for living organisms including humans. However, its excess is associated with pathological conditions. Cobalt poisoning can be caused for example by exposure to cobalt metal dust during the production of hard metals or follow the corrosion of metal hip prosthesis. Patients intoxicated by cobalt can develop different manifestations including neurological impairment, hypothyroidism or cardiomyopathy. The aim of this work is to prepare a standardized, rapid, cheap but precise method for the screening of cobalt chelators. For this purpose, spectrophotometric detection using 1-nitroso-2-nafphhol-3,6-disulfonic acid disodium salt as the indicator was used. Firstly, it was found that the addition of cobalt ions led to a clear bathochromic shift of the maximum absorbance of the indicator. The relationship between the absorbance and cobalt concentration was highly linear from 470 to 560 nm at all 4 tested pH conditions (4.5, 5.5, 6.8 and 7.5). The sensitivity of the method...

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical botanic and ekology Candidate: Nikol Vavřichová Supervisor: Ing. Kateřina Macáková Ph.D. Title of diploma thesis: Iron - chelating effects of flavonoid metabolites - small polyphenolic substances (2015/2016) Iron is a trace element which is necessary for function of an organism. There is no specific excretion mechanism for iron, therefore any deflection causes deficiency or abundance. Iron abundance leads to hemochromatosis. An application of iron chelators is a treatment of choice for hemochromatosis. There are three clinically used chelators for treatment of iron overload: deferoxamine, deferasirox and deferiprone. These drugs are inappropriate for therapy (side effects, dosage form). Therefore there is a place for serching for new types of medicine for treatment of hemochromatosis. Flavonoids are natural substances with positive influence on a human organism. The most investigated effects are antioxidant and chelating activity. As flavonoids are metabolised in a human body, there is an arising question if flavonoid metabolites are also able to chelate iron ions. For this work we chose derivates of benzoic acid: benzoic acid, 3 - hydroxybenzoic acid, 4 - hydroxybenzoic acid, 2,4 - dihydroxybenzoic...

Dočekalová L., Iron-chelating activity of selected alkaloids III, Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical botanic and ecology, Hradec Králové, 2016, 60 pp. Iron is important trace element necessary for human organism. When excess it develops free radicals and structures of organism are harmed. It can lead to organ failure. Excess is solved with chelators, the most used is deferoxamine. But his terapeutic regimen is disadvantageous and it has a lot of side effects. That's reason for searching for substances with better features. This paper focuses on studium of iron-chelating activity of selected alkaloids from family Amaryllidaceae. Concretely, it's galanthamine, undulatine, buphanisine, caranine, 1-O- acetylbulbisine, homolycorine, tazettine, galanthamine, chlidanthine, ambelline, haemanthamine, haemanthidine, hamayne, 9-O-demethylgalanthine and lycoramine. As standard for comparison of activity was used deferoxamine. Activity was measured by spectrophotometer. As indicator was used ferrozine. Chelatation was measured for ferrous ionts and for total iron, where hydroxylamine as reduction agent was used. Ferrous ionts was measured also with pH alteration. Highest activity reached deferoxamine in all executed measurements. In...

Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Botany Consultant: Ing. Kateřina Macáková, Ph. D. Student: Markéta Šilhová Title of Thesis: Interactions of alkaloids with transition metals II. Copper is an important component of the human body. It is involved in the right functioning of organ systems and is also a part of many important body enzymes. It is necessary to maintain a balanced amount of copper in the body in order to avoid excess or deficiency, which can lead to various diseases. The aim of this diploma thesis was to determine the copper chelating and copper reducing effects of isoquinoline alkaloids berberine chloride, canadine, corydaline, sculerine, sinactine, stylopine, tetrahydropalmatine, allocryptopine, protopine, corycavamine and cryptopine. In experimental measurements the determination of chelation of copper ions with hemytoxyline and the determination of chelation and reduction of copper ions using disodium salt of bathocuproindisulfonic acid was performed. The highest reducing activity was exhibited by scoulerine, whose structure in comparison with other alkaloids contains hydroxyl groups and which has been exhibited in the past to inhibit the growth of tumour cell. The lowest reducing activity was measured for protopine alkaloids and...

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Radka Rzepecká Supervisor: Ing. Kateřina Macáková, Ph.D. Title of Thesis: Interactions of alkaloids with transition metals I. Copper is one of the essential trace elements that are necessary for the proper functioning of the organism. Copper is a significant component of many enzymes that affect various metabolic processes in the human body. It is important that the level of copper in the body is regulated because its deficit or excess lead to a variety of pathological conditions. Alkaloids are secondary plant metabolites that are distinguished by numerous biological activities. In this thesis the copper-chelating and copper-reducing activity of eleven isoquinoline alkaloids was measured: boldine, isocorydine, (+)-bulbocapnine, (+)-corydine, glaucine, (-)-sinoacutine, (-)-californidine, (-)-escholtzine, platycerine, (-)-fumaricine, and (+)- parfumine. Alkaloid activity was measured at four (patho) physiological pH values by a verified spectrophotometric method using two indicators: bathocuproinedisulfonic acid disodium salt and hematoxylin. Based on the results, structure-effect relationships were derived. The results show that none of the tested substances was able to chelate copper ions. In...

v angličtině Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Lucie Pohanová Supervisor: Assoc. Prof.. Přemysl Mladěnka, Pharm.D., Ph.D. Title of Thesis: Chelation of ferrous ions by xanthen-3-one derivatives Iron is an essential element important for proper function of cells. Imbalance of iron levels can lead to serious diseases. Since there is no excretory mechanism, the homeostasis is regulated at the level of absorption in the intestine. The iron overload, which leads to tissue damage due to catalysis of the formation of free radicals, occur because of genetic disorders such as hemochromatosis or owing to frequent administration of transfusions. Rational therapy for iron overload is the administration of the chelators. The aim of this study was to evaluate the ability of derivatives of 2,6,7- trihydroxyxanthen-3-one (synthesized at the University of Sarajevo - Dr. Durić) to chelate iron in 4 (patho) physiologically relevant pH conditions. The ferrozine spectrophotometric method was used to determine the degree of chelation. Measurements showed dependency of the chelating effect on pH: lowering pH resulted in the decrease of the effect. At pH 7.5, most of the substances showed 100% ferrous ion chelation in the stoichiometric ratio of 1...

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Kateřina Klimková Supervisor: Assoc. Prof. Přemysl Mladěnka, Pharm. D., Ph.D. Consultant: Assoc. Prof. Kateřina Valentová, Ph.D. Title of Thesis: Determination of the stoichiometry of the copper complexes with dehydrosilybin A Silymarin, the standardized extract of the milk thistle (Silybum marianum), is a widely used approved over-the-counter drug that is recommended for a number of liver diseases. Silymarin contains as one of its components 2,3-dehydrosilybinA, which has an appropriate metal binding site in its structure. In general, flavonolignans, due to their structure, can interact with transition metals in the gastrointestinal tract by forming complexes. This property can be useful for the protection against excessive amounts of metals in the body. The aim of this in vitro study was to analyse the interaction of 2,3-dehydrosilybin A with copper, which plays a crucial role in the organism as a cofactor of many enzymes. Although being an essential element, it can, however, be toxic at elevated levels. Stoichiometry, as one of the most important characteristics of the complex, was determined by UV-Vis spectrophotometry in four (patho)physiological pH conditions (4.5; 5.5; 6.8; 7.5)...

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Lenka Loskotová Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Title of Thesis: Interactions of alkaloids with transition metals IV. Copper is a biogenic trace element that participates in the proper function of an organism. It is part of a number of enzymes and participates in metabolic processes in the human body. The level of copper in the organism should be regulated to avoid its excess or deficit, as pathologies could occur. Alkaloids are natural nitrogenous substances of alkaline nature. We find many biological activities in them. The aim of this thesis was to measure copper-chelating and copper- reducing activity of isoquinoline alkaloids: corypalmine, thalictricavine, 8-oxoberberine, fumarilin, norisocorydine and laurotetanine. Alkaloid activity was measured at different pH environments (4.5; 5.5; 6.8 and 7.5) and in the DMSO environment by a spectrophotometric method using hematoxyline and acid disodium salt bathocuproindisulfonic. Based on the results, structure-effect relationships were derived. In experimental measurement, it was found that none of us tested alkaloids showed chelating activity. Reduction activity has been demonstrated in all test substances. The lowest activity...

Charles University Pharmaceutical Faculty in Hradec Králové Department of Pharmaceutical Botany Candidate: Bc. Martin Cymbál, DiS. Supervisor: doc. Ing. Kateřina Macáková, Ph.D. Diploma thesis 2019/2020: Interactions of alkaloids with transition metals III., pp. 86. Copper is one of the important trace elements in the body. It regulates various enzymatic pathways. This work monitors the chelating and reducing activity of isochinoline alkaloids of the family Amaryllidaceae. The alkaloids of Amaryllidaceae have a large number of effects such as analgesic, narcotic, antiarrhythmic, antihypertensive, bronchodilatory, chemotherapeutic, antiparasitic, uteretonic, locally anesthetic, mydriatic and many other significant effects. An important representative is galanthamine hydrobromide, which is therapeutically used and is an inhibitor of acetylcholinesterase. Galanthamine type alkaloids (galanthamine, galanthamine hydrobromide, chlidanthine), lycorine type (lycorine, galanthine), haemanthamine type (haemanthnamine, vittatine) and montanine type (montanine) were studied. The methodology of the work was to determine the chelating and reducing activity with the use of the hematoxylin indicator and bathocuproindisulfonic acid, at different pH or in dimethylsulfoxide. Of the alkaloids studied, galanthamine and...

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Candidate: Lukáš Konečný Supervisor: prof. Přemysl Mladěnka, Pharm.D., Ph.D. Title of Thesis: Preparation of a method for detection of the extent of chelation of calcium and magnesium ions Calcium and magnesium are biogenic elements belonging to the second group of the periodic table. Calcium is the fifth most abundant element in the human body. In addition to its important role in bone homeostasis, calcium is involved in other processes such as blood clotting, muscle contraction and regulation of nerve excitability Magnesium is the cofactor of many enzymatic reactions essential for a row of physiological functions. The aim of this work was to propose a novel screening method for determination of the degree of calcium and magnesium chelation. In the first step the UV-vis spectra of the selected indicator o-cresolphthalein complexone and its complexes with calcium and magnesium were measured. This was followed by verification of the linearity and the determination of the sensitivity of the method. Concurrently the stability of the indicator and its complexes with both ions was measured. In the last step, the suitability of the method was verified on a standard chelator ethylenediaminetetraacetic acid...