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Molecular mechanisms of LDL-cholesterol induced endothelial dysfunction
Rojková, Tereza ; Petrezsélyová, Silvia (advisor) ; Šeda, Ondřej (referee)
Hypercholesterolemia, defined as elevated LDL-cholesterol levels in the blood, develops either as a result of genetic predispositions, unhealthy lifestyle, underlying diseases, or as a result of a combination of these factors. LDL-cholesterol is sometimes called "bad" cholesterol because its excess negatively affects the vessel`s innermost layer - endothelium, Endothelium is unique for its vasodilatory, vasoconstrictive, anti-inflammatory, and anti- coagulant function but also for its ability to control vascular permeability. In the case of hypercholesterolemia, cholesterol gradually accumulates in the subendothelial space and reduces levels of the main modulatory molecule of the endothelium - nitric oxide by several mechanisms. In endothelial dysfunction, oxidative stress increases, LDL-cholesterol is oxidized, endothelial cells are activated and produce proinflammatory cytokines and adhesive molecules. Endothelial dysfunction is considered the first stage of atherosclerosis, as monocytes enter the site of inflammation and differentiate into macrophages, which subsequently turn into foam cells by endocytosis of oxidized LDL-cholesterol. In this way, atherosclerotic plaques are formed, which not only narrow the blood vessels, but plaques can erupt, causing subsequent thrombosis, which can result...
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Monocyte adhesion to endothelium and atherogenesis
Kauerová, Soňa
Despite the availability of effective therapy of hypercholesterolemia and hypertension, cardiovascular mortality continues to be very high in the Western world. Inflammatory changes occurring in the arterial wall as well as in the adipose tissue play a major role in the development of atherosclerosis. Macrophages are involved in the process of atherogenesis as early as atherosclerosis begins to develop, when, still as monocytes, they migrate and adhere to the arterial wall as a result of endothelial activation and stimulation by pro-inflammatory substances. Adipose tissue has long been recognized as an important endocrine organ, with part of adipose tissue made up by a large amount of macrophages capable of producing a large number of pro-inflammatory cytokines, which contribute to the development of low-grade chronic inflammation important in the development of atherosclerosis. In samples of subcutaneous, visceral and perivascular adipose tissue (SAT, VAT, and PVAT, respectively) obtained from healthy subjects (living kidney donors, LKD), we analyzed macrophages and their polarization, gene expression of pro-inflammatory cytokines and the effect of substances released by VAT on the level of monocyte adhesion to the endothelium. In some analyses, we included samples of SAT, VAT and PVAT obtained...
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Phenotypical characterization of the healthy human cornea and the alterations caused by posterior polymorphous corneal dystrophy
Reinštein Merjavá, Stanislava ; Jirsová, Kateřina (advisor) ; Martínek, Jindřich (referee) ; Čejková, Jitka (referee)
Purpose: The aim of this work was to characterize the healthy human cornea and the cornea of patients suffering from posterior polymorphous corneal dystrophy (PPCD) using different antibodies. Despite the fact that PPCD is a very rare disorder, one of the largest groups of PPCD patients in the world comes from the Czech Republic. This offers us the opportunity to investigate the changes on the clinical, cellular and molecular levels. Material and Methods: A collection of 25 control corneas as well as 16 pathological corneas from PPCD patients were used. Epithelial (cytokeratins) and mesothelial markers (mesothelin, calbindin 2, HBME-1 protein) were detected in all layers of the healthy corneas using immunocyto- and immunohistochemistry. The expression of all markers was confirmed using molecular methods as well (RT-PCR and Western blot). Changes in the expression of cytokeratins and changes in the extracellular matrix structure (collagen IV and VIII) were studied in the PPCD corneas. Combined fluorescent immunohistochemistry with fluorescence in situ hybridization were used in order to characterize the origin of abnormal cells on the posterior graft surface, which cause the recurrence of the PPCD after penetrating keratoplasty surgery. Results: Changes in the cytokeratin expression (strong...
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Monocyte adhesion to endothelium and atherogenesis
Kauerová, Soňa
Despite the availability of effective therapy of hypercholesterolemia and hypertension, cardiovascular mortality continues to be very high in the Western world. Inflammatory changes occurring in the arterial wall as well as in the adipose tissue play a major role in the development of atherosclerosis. Macrophages are involved in the process of atherogenesis as early as atherosclerosis begins to develop, when, still as monocytes, they migrate and adhere to the arterial wall as a result of endothelial activation and stimulation by pro-inflammatory substances. Adipose tissue has long been recognized as an important endocrine organ, with part of adipose tissue made up by a large amount of macrophages capable of producing a large number of pro-inflammatory cytokines, which contribute to the development of low-grade chronic inflammation important in the development of atherosclerosis. In samples of subcutaneous, visceral and perivascular adipose tissue (SAT, VAT, and PVAT, respectively) obtained from healthy subjects (living kidney donors, LKD), we analyzed macrophages and their polarization, gene expression of pro-inflammatory cytokines and the effect of substances released by VAT on the level of monocyte adhesion to the endothelium. In some analyses, we included samples of SAT, VAT and PVAT obtained...
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Use of corneal endothelium and amniotic membrane for transplantation purposes.
Šmeringaiová, Ingrida ; Jirsová, Kateřina (advisor) ; Netuková, Magdaléna (referee) ; Čejková, Jitka (referee)
Part I: Endothelial cells form the posterior layer of the cornea and are important for maintaining its transparency. Dysfunctional endothelium can only be restored by transplantation. The global shortage of donor corneas requires the search for alternative treatments. The preparation of the graft by tissue engineering methods is complicated by low proliferative capacity of endothelium. To date, no endothelium-specific marker has been defined and the existence of endothelial stem cells has not been confirmed yet. We have prepared a protocol for culturing endothelial cells from research-grade tissue - corneoscleral rims obtained after transplantation or corneas excluded from the transplant process. We monitored localization of selected proteins, including stem cell markers, in native tissue and in primary cell cultures. We prepared up to 6.4 cm2 of endothelium from one cornea/rim, which had cellular features comparable to the native endothelium. This approach can increase the amount of endothelium for research or transplantation purposes. Using indirect immunohistochemistry, we showed that none of the previously proposed endothelial molecular markers is specific for these cells. We detected the expression of stem cell markers throughout the endothelial layer. In the porcine cornea model, we monitored...
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Monocyte adhesion to endothelium and atherogenesis
Kauerová, Soňa ; Králová Lesná, Ivana (advisor) ; Kraml, Pavel (referee) ; Kuneš, Jaroslav (referee)
Despite the availability of effective therapy of hypercholesterolemia and hypertension, cardiovascular mortality continues to be very high in the Western world. Inflammatory changes occurring in the arterial wall as well as in the adipose tissue play a major role in the development of atherosclerosis. Macrophages are involved in the process of atherogenesis as early as atherosclerosis begins to develop, when, still as monocytes, they migrate and adhere to the arterial wall as a result of endothelial activation and stimulation by pro-inflammatory substances. Adipose tissue has long been recognized as an important endocrine organ, with part of adipose tissue made up by a large amount of macrophages capable of producing a large number of pro-inflammatory cytokines, which contribute to the development of low-grade chronic inflammation important in the development of atherosclerosis. In samples of subcutaneous, visceral and perivascular adipose tissue (SAT, VAT, and PVAT, respectively) obtained from healthy subjects (living kidney donors, LKD), we analyzed macrophages and their polarization, gene expression of pro-inflammatory cytokines and the effect of substances released by VAT on the level of monocyte adhesion to the endothelium. In some analyses, we included samples of SAT, VAT and PVAT obtained...
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Monocyte adhesion on the endothelium in vitro
Kubátová, Hana ; Králová Lesná, Ivana (advisor) ; Galovcová, Markéta (referee)
Cardiovascular diseases are the major causes of death worldwide. Studying factors leading to initiation and progression of atherosclerosis and its complications leads to a better understanding of underlying mechanisms of this disease and to development of novel treatments. Adhesion of monocytes on the endothelial surface is the initial step of atherosclerosis. The main aim of this study was to establish and test an in vitro model of monocyte adhesion on the endothelial cells and to evaluate the results by means of two methods - measuring the fluorescence signal intensity and counting adhered cells. Because of its well known effects on endothelial cells activation and adhesion molecules expression TNF-α was chosen for endothelial cells stimulation. The lowest concentration of TNF-α affecting the percentage of adhered monocytes in comparision with negative control was 1 ng TNF-α/ml. The optimal concentration of TNF-α increasing the percentage of adhered monocytes was 10 ng TNF-α/ml. The influence of TNF-α on the adhesion was observed already after 5 minutes of coincubation of THP-1 monocytes with HUVEC. Using the optimal concentration of 10 ng/ml led to the highest percentage of adhered monocytes after 30 - 40 minutes of coincubation with HUVEC. Other factor affecting the percentage of adhered...
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Phenotypical characterization of the healthy human cornea and the alterations caused by posterior polymorphous corneal dystrophy
Reinštein Merjavá, Stanislava ; Jirsová, Kateřina (advisor) ; Martínek, Jindřich (referee) ; Čejková, Jitka (referee)
Purpose: The aim of this work was to characterize the healthy human cornea and the cornea of patients suffering from posterior polymorphous corneal dystrophy (PPCD) using different antibodies. Despite the fact that PPCD is a very rare disorder, one of the largest groups of PPCD patients in the world comes from the Czech Republic. This offers us the opportunity to investigate the changes on the clinical, cellular and molecular levels. Material and Methods: A collection of 25 control corneas as well as 16 pathological corneas from PPCD patients were used. Epithelial (cytokeratins) and mesothelial markers (mesothelin, calbindin 2, HBME-1 protein) were detected in all layers of the healthy corneas using immunocyto- and immunohistochemistry. The expression of all markers was confirmed using molecular methods as well (RT-PCR and Western blot). Changes in the expression of cytokeratins and changes in the extracellular matrix structure (collagen IV and VIII) were studied in the PPCD corneas. Combined fluorescent immunohistochemistry with fluorescence in situ hybridization were used in order to characterize the origin of abnormal cells on the posterior graft surface, which cause the recurrence of the PPCD after penetrating keratoplasty surgery. Results: Changes in the cytokeratin expression (strong...
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