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The study of model lipid membranes containing omega-hydroxylated ceramides
Svatošová, Linda ; Opálka, Lukáš (advisor) ; Pullmannová, Petra (referee)
Charles University, Faculty of pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Linda Svatošová Supervisor: PharmDr. Lukáš Opálka, Ph.D. Title of diploma thesis: The study of model lipid membranes containing omega- hydroxylated ceramides Acylceramides (EO-Cer) belong to a class of ceramides (Cer) with an ultralong acyl chain whose ω-hydroxyl group is esterified with linoleic acid. The importance of EO-Cer lies in the formation of the long periodicity phase (LPP) and the corneocyte lipid envelope (CLE), which are indispensable components for the skin functioning as a barrier. Disorders in EO-Cer biosynthesis are associated with insufficient production of CLE and LPP leading to many skin diseases, including some types of ichthyosis. One of the enzymes that is deficient in such ichthyoses is PNPLA1. Insufficient function of this enzyme disables ω-esterification with linoleic acid, and thus the formation of EO-Cer. On the contrary, their precursors, i.e. ω-hydroxylated ceramides (O-Cer), are cumulated. The aim of this thesis was to prepare model membranes containing O-Cer and to study the effects of O-Cer on the lipid organization and barrier properties of model membranes. Within this thesis, two types of membranes were prepared - the first type were membranes...
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The effect of Ca2+cations and cholesteryl sulfate on the human skin barrier model
Kelemanová, Aneta ; Pullmannová, Petra (advisor) ; Paraskevopoulou, Anna (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Aneta Kelemanová Supervisor: Mgr. Petra Pullmannová, Ph.D. Title of diploma thesis: The effect of Ca2+ cations and cholesteryl sulfate on the human skin barrier model The structure and composition of the outermost layer of the epidermis, the stratum corneum, form a skin barrier to transepidermal water loss. The main components of the stratum corneum are corneocytes and the intercellular lipid matrix. The intercellular lipid matrix is a mixture of ceramides, cholesterol, and free fatty acids. Cholesterol esters, such as cholesteryl sulfate, are also present. This unique lipid mixture forms a multilamellar layer with short and long crystalline phases with periodicities of approximately 6 and 13 nm. A separated cholesterol phase with a periodicity of about 3,4 nm can also be found in the stratum corneum. The most common lateral packing of the lipid mixture is orthorhombic. Hexagonal or fluid packing is less common. The aim of this diploma thesis was to optimize the conditions for spontaneous arrangement of the isolated human skin lipids in an aqueous medium with the addition of Ca2+ cations and cholesteryl sulfate. A human skin barrier model was created from the prepared lipid dispersion...
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The human skin barrier model containing stripped stratum corneum
Soukupová, Romana ; Pullmannová, Petra (advisor) ; Kováčik, Andrej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Romana Soukupová Supervisor: Mgr. Petra Pullmanová, Ph.D. Title of diploma thesis: The human skin barrier model containing stripped stratum corneum The uppermost layer of the epidermis, the stratum corneum, acts as a protective skin barrier. It contains a lipid matrix, which is made up of ceramides, cholesterol, and free fatty acids. The composition and arrangement of these lipids are necessary for the proper function of the skin barrier. Corneocytes, which do not have nuclei, are distributed in the lipid matrix. They are surrounded by insoluble proteins with covalently bound lipids on their surface, creating the corneocyte lipid envelope. The aim of this diploma thesis was to prepare models of the human skin barrier using an isolated stratum corneum with a preserved corneocyte lipid envelope and without a preserved corneocyte lipid envelope, and then monitor and compare the lipid arrangements in these models. Obtaining the stratum corneum from the skin samples was necessary to prepare the models. Human skin lipids were extracted from isolated stratum corneum and part of this delipidated stratum corneum was saponified. Skin lipids were purificated by column chromatography, and their...
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Preparation of the human skin barrier model using thin lipid film deposition
Suciu-Šubert, Karina ; Pullmannová, Petra (advisor) ; Opálka, Lukáš (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Student: Karina Suciu-Šubert Supervisor: Mgr. Petra Pullmannová, Ph.D. Title of diploma thesis: Preparation of the human skin barrier model by using thin lipid film deposition The uppermost part of the human skin - the stratum corneum, which protects the body from the external environment, is made up of cornified cells - corneocytes, which are surrounded by the extracellular matrix of highly ordered lipids: ceramides (Cer), fatty acids and cholesterol. The protective barrier is constantly renewed with so-called keratinocytes, which differentiate to corneocytes and finally desquamate from skin to surface. The corneocyte envelope replaces plasma membrane of corneocytes. It consists of proteins (eg. involucrin) and a lipid monolayer consisting mainly of ω-hydroxyceramides which are attached to the protein segments by covalent bonds. The task of this diploma thesis was the preparation of the human skin barrier model by using thin lipid film deposition. Two different lipid mixtures were based on Cer NS or Cer EOS and NS. The mixtures were applied on the hydrophilic or hydrophobic substrate by spraying with Linomat V. The amount of lipids and consequently the number of theoretical lipid layers on the...
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The effect of Ca2+cations and cholesteryl sulfate on the human skin barrier model
Kelemanová, Aneta ; Pullmannová, Petra (advisor) ; Paraskevopoulou, Anna (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Aneta Kelemanová Supervisor: Mgr. Petra Pullmannová, Ph.D. Title of diploma thesis: The effect of Ca2+ cations and cholesteryl sulfate on the human skin barrier model The structure and composition of the outermost layer of the epidermis, the stratum corneum, form a skin barrier to transepidermal water loss. The main components of the stratum corneum are corneocytes and the intercellular lipid matrix. The intercellular lipid matrix is a mixture of ceramides, cholesterol, and free fatty acids. Cholesterol esters, such as cholesteryl sulfate, are also present. This unique lipid mixture forms a multilamellar layer with short and long crystalline phases with periodicities of approximately 6 and 13 nm. A separated cholesterol phase with a periodicity of about 3,4 nm can also be found in the stratum corneum. The most common lateral packing of the lipid mixture is orthorhombic. Hexagonal or fluid packing is less common. The aim of this diploma thesis was to optimize the conditions for spontaneous arrangement of the isolated human skin lipids in an aqueous medium with the addition of Ca2+ cations and cholesteryl sulfate. A human skin barrier model was created from the prepared lipid dispersion...
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The human skin barrier model containing stripped stratum corneum
Soukupová, Romana ; Pullmannová, Petra (advisor) ; Kováčik, Andrej (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Romana Soukupová Supervisor: Mgr. Petra Pullmanová, Ph.D. Title of diploma thesis: The human skin barrier model containing stripped stratum corneum The uppermost layer of the epidermis, the stratum corneum, acts as a protective skin barrier. It contains a lipid matrix, which is made up of ceramides, cholesterol, and free fatty acids. The composition and arrangement of these lipids are necessary for the proper function of the skin barrier. Corneocytes, which do not have nuclei, are distributed in the lipid matrix. They are surrounded by insoluble proteins with covalently bound lipids on their surface, creating the corneocyte lipid envelope. The aim of this diploma thesis was to prepare models of the human skin barrier using an isolated stratum corneum with a preserved corneocyte lipid envelope and without a preserved corneocyte lipid envelope, and then monitor and compare the lipid arrangements in these models. Obtaining the stratum corneum from the skin samples was necessary to prepare the models. Human skin lipids were extracted from isolated stratum corneum and part of this delipidated stratum corneum was saponified. Skin lipids were purificated by column chromatography, and their...
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Synthesis of phytoceramide analogues and evaluation of their effects on the skin barrier properties
Tesař, Ondřej ; Vávrová, Kateřina (advisor) ; Pullmannová, Petra (referee)
Charles University in Prague Faculty of Pharmacy in Hradci Králové Deparment of Inorganic and Organic Chemistry Candidate: Ondřej Tesař Supervisor: doc. PharmDr. Kateřina Vávrová, Ph.D. Title of diploma thesis: Synthesis of phytoceramide analogues and evaluation of their effect on the skin barrier properties. Phytoceramides (FCER) belong to the class of sphingolipids. They are composed of a basic alcohol phytosphingosine (P) and the acyl chain. Together with the other lipids they create the extracellular membrane in human stratum corneum (SC), the uppermost layer of the skin, which protects us against the loss of water and penetration of foreign compounds into our body. The influence of FCER structure on the function of this membrane is unknown yet. Aim of the work: The aim of this work was to examine what role the acyl chain length of FCER plays in this membrane impermeability. Methods: My task was to synthetize FCER with acyl chain length of 2, 4, 6 and 24 carbons and preparation of SC model membranes containing FCER with acyl chain length of 2, 4, 6, 8 or 24 carbons, cholesterol, lignoceric acid and cholesterol sulfate. The permeabilities of the model membranes were evaluated in Franz diffusion cells. Electric impedance and permeability for two model drugs: theophylline (TH) and indomethacin...
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Optimization of the skin barrier model with isolated ceramides of human stratum corneum
Dulanská, Lucia ; Pullmannová, Petra (advisor) ; Zbytovská, Jarmila (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Lucia Dulanská Supervisor: Mgr. Petra Pullmannová, Ph.D Title of thesis: Optimization of the skin barrier model with isolated ceramides of human Stratum corneum Stratum corneum (SC), the uppermost layer of the skin, regulates transcutaneous water loss and protects against outer conditions and harmful substances. It consists of cornified cells - corneocytes and extracellular lipid matrix, which is responsible for the barrier functions. Corneocytes are covered with covalently bound lipids creating the corneocyte lipid envelope (CLE). CLE is considered to interconnect the extracellular lipids with corneocytes and to have a templating effect. We aimed to optimize a skin lipid model simulating also the presence of CLE. The lipidic part of the model was prepared from an equimolar mixture of isolated human skin ceramides (hCer), cholesterol and free fatty acids (FFA, either protonated or deuterated) with 5 weight % of cholesteryl sulfate. hCer were extracted from the isolated human SC and purified by the column chromatography. The composition of hCer was determined by the high- performance thin-layer chromatography. The reverse-phase and normal phase silica gel particles served as the CLE...
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The study of model lipid membranes containing omega-hydroxylated ceramides
Svatošová, Linda ; Opálka, Lukáš (advisor) ; Pullmannová, Petra (referee)
Charles University, Faculty of pharmacy in Hradec Králové Department of Organic and Bioorganic Chemistry Candidate: Linda Svatošová Supervisor: PharmDr. Lukáš Opálka, Ph.D. Title of diploma thesis: The study of model lipid membranes containing omega- hydroxylated ceramides Acylceramides (EO-Cer) belong to a class of ceramides (Cer) with an ultralong acyl chain whose ω-hydroxyl group is esterified with linoleic acid. The importance of EO-Cer lies in the formation of the long periodicity phase (LPP) and the corneocyte lipid envelope (CLE), which are indispensable components for the skin functioning as a barrier. Disorders in EO-Cer biosynthesis are associated with insufficient production of CLE and LPP leading to many skin diseases, including some types of ichthyosis. One of the enzymes that is deficient in such ichthyoses is PNPLA1. Insufficient function of this enzyme disables ω-esterification with linoleic acid, and thus the formation of EO-Cer. On the contrary, their precursors, i.e. ω-hydroxylated ceramides (O-Cer), are cumulated. The aim of this thesis was to prepare model membranes containing O-Cer and to study the effects of O-Cer on the lipid organization and barrier properties of model membranes. Within this thesis, two types of membranes were prepared - the first type were membranes...
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Optimization of the skin barrier model with isolated ceramides of human stratum corneum
Dulanská, Lucia ; Pullmannová, Petra (advisor) ; Zbytovská, Jarmila (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Author: Lucia Dulanská Supervisor: Mgr. Petra Pullmannová, Ph.D Title of thesis: Optimization of the skin barrier model with isolated ceramides of human Stratum corneum Stratum corneum (SC), the uppermost layer of the skin, regulates transcutaneous water loss and protects against outer conditions and harmful substances. It consists of cornified cells - corneocytes and extracellular lipid matrix, which is responsible for the barrier functions. Corneocytes are covered with covalently bound lipids creating the corneocyte lipid envelope (CLE). CLE is considered to interconnect the extracellular lipids with corneocytes and to have a templating effect. We aimed to optimize a skin lipid model simulating also the presence of CLE. The lipidic part of the model was prepared from an equimolar mixture of isolated human skin ceramides (hCer), cholesterol and free fatty acids (FFA, either protonated or deuterated) with 5 weight % of cholesteryl sulfate. hCer were extracted from the isolated human SC and purified by the column chromatography. The composition of hCer was determined by the high- performance thin-layer chromatography. The reverse-phase and normal phase silica gel particles served as the CLE...
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