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Induction of beta-cell proliferation by synthetic modified mRNAs encoding cell cycle regulators
Ivanovská, Dana ; Koblas, Tomáš (advisor) ; Černá, Věra (referee)
Diabetes mellitus is a metabolic disease associated with a high blood glucose level over a prolonged period of time. Hyperglycemia is caused by the loss of pancreatic insulin producing beta cells. Diabetes mellitus II is linked with insulin resistence, which can indirectly lead to beta cell deficiency. It logically follows that the replacement or regeneration of beta cells could lead to a successful remission of diabetes. D type cyclins (D1, D2, D3) and cyclin-dependent kinases (Cdk) 4/6 appear to have the potential to induce beta cell proliferation. These proteins are responsible for driving cell mitotic entry. The aim of this bachelor thesis was to verify the possibility of inducing beta cell proliferation via D type and Cdk4/6 synthetic mRNA transfection. In vitro-synthesized mRNA induces short-therm protein overexpression. Cyclins harboring mutations are characterized by a higher protein stability and an increased half-life. The presence of D type cyclins and Cdk4/6 after cell transfection was detected using indirect immunofluorescence. Also a Western blot analysis with subsequent immunodetection was performed. Transfecting rat islet cells with various D type cyclins and Cdk4/6 mRNA combinations has shown to lead to a significant induction of beta cell proliferation. The levels of beta cell...
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Preparation and characterization of vesiculin, a two-chain protein derived from IGF-2
Mrzílková, Karolína ; Žáková, Lenka (advisor) ; Pačesová, Andrea (referee)
Hormones of insulin family are one of the most studied groups of proteins due to their connection to large number of diseases including type two diabetes mellitus, tumorigenesis and some neurodegenerative diseases. The newest member of this superfamily is a two-chain analogue of IGF-2 called vesiculin. This peptide was originally isolated from secretory granules of mouse βTC6-F7 cell line and is currently believed to have a endocrine or paracrine effect on pancreatic β-cells. Its sequence homology with IGF-2 and structural similarity to insulin foreshadows vesiculin's potential metabolic, proliferation and growth properties and further secures its place as scientifically interesting and clinically lucrative topic. The insulin theme is corelated with insulin resistance, pathological state present primarily in early stages of development of type two diabetes mellitus. Vesiculin is able to stimulate glucose uptake and glycogen synthesis even in this condition which differentiates it form insulin and IGF-2 whose glucoregulatory activity is blunted in face of insulin resistance. Further research of vesiculin and insulin family receptor interaction, including dimeric tyrosinekinase receptor for IGF-1 and insulin, but also monomeric IGF-2 receptor, can provide more knowledge on character of this binding...
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Differentiation of adult stem cells into insulin-producing beta cells
Koblas, Tomáš
Ph.D. Thesis abstract: Diabetes mellitus is a chronic disease characterized by a metabolic disorder in which there is a low level or complete lack of the insulin. Diabetes mellitus type 1 (DM1) is caused by an autoimmune reaction leading to the destruction of the insulin producing beta cells in the pancreas. In consequence, low or non-existent insulin production leads to a complete dependence on exogenous insulin supplementation. DM1 causes serious long-term complications. Although strict control of blood sugar could prevent the onset and development of diabetic complications only 5% of diabetic patients are able to achieve such control. Hence it is evident that the current methods of treatment are neither sufficient to treat this disease, nor prevent late complications in most patients. The most promising therapeutic approach in the treatment of diabetes is the restoring of insulin production. One such method is the transplantation of insulin-producing tissue. However, a lack of available insulin- producing tissue limits such therapeutic approach. Therefore an alternative source of insulin producing cells have to be found to obtain a sufficient amount of safe and efficient insulin producing tissue. Pancreatic stem/progenitor cells could represent such an available alternative source. Despite the evidence...
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Induction of beta-cell proliferation by synthetic modified mRNAs encoding cell cycle regulators
Ivanovská, Dana ; Koblas, Tomáš (advisor) ; Černá, Věra (referee)
Diabetes mellitus is a metabolic disease associated with a high blood glucose level over a prolonged period of time. Hyperglycemia is caused by the loss of pancreatic insulin producing beta cells. Diabetes mellitus II is linked with insulin resistence, which can indirectly lead to beta cell deficiency. It logically follows that the replacement or regeneration of beta cells could lead to a successful remission of diabetes. D type cyclins (D1, D2, D3) and cyclin-dependent kinases (Cdk) 4/6 appear to have the potential to induce beta cell proliferation. These proteins are responsible for driving cell mitotic entry. The aim of this bachelor thesis was to verify the possibility of inducing beta cell proliferation via D type and Cdk4/6 synthetic mRNA transfection. In vitro-synthesized mRNA induces short-therm protein overexpression. Cyclins harboring mutations are characterized by a higher protein stability and an increased half-life. The presence of D type cyclins and Cdk4/6 after cell transfection was detected using indirect immunofluorescence. Also a Western blot analysis with subsequent immunodetection was performed. Transfecting rat islet cells with various D type cyclins and Cdk4/6 mRNA combinations has shown to lead to a significant induction of beta cell proliferation. The levels of beta cell...
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Possibilities of prediction and immunointervention in type 1 diabetes
Sklenářová, Jana ; Štechová, Kateřina (advisor) ; Saudek, František (referee) ; Pavlínková, Gabriela (referee)
Type 1 diabetes mellitus (T1D) is an organ-specific autoimmune disease characterised by autoimmune destruction of insulin-producing beta cells in the islets of Langerhans. It is a long-term process initiated months or even years prior to the clinical onset. The main role in the pathogenesis is played by T lymphocytes but other cell types are involved as well. The presence of autoantibodies in the circulation is typical even before the disease onset. Nowadays, intensive research is focused on finding individuals at risk and developing an effective prevention. During my postgraduate studies I was involved mainly in the research of T1D prediction and prevention. We investigated the relationship of established autoimmune markers - autoantibodies - and the cellular reactivity to GAD65 and IA2 autoantigens. We discovered that the reaction to autoantigens is very individual and it is influenced by the patient's autoantibody profile. These results could be relevant in planning antigen-specific immunointervention studies and improving their efficacy. We also made an attempt to improve specificity and sensitivity of a beta cell destruction marker (specifically demethylated DNA), which would enable better understanding of the beta cell decline and identification of individuals at risk of T1D development. In...
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Differentiation of adult stem cells into insulin-producing beta cells
Koblas, Tomáš
Ph.D. Thesis abstract: Diabetes mellitus is a chronic disease characterized by a metabolic disorder in which there is a low level or complete lack of the insulin. Diabetes mellitus type 1 (DM1) is caused by an autoimmune reaction leading to the destruction of the insulin producing beta cells in the pancreas. In consequence, low or non-existent insulin production leads to a complete dependence on exogenous insulin supplementation. DM1 causes serious long-term complications. Although strict control of blood sugar could prevent the onset and development of diabetic complications only 5% of diabetic patients are able to achieve such control. Hence it is evident that the current methods of treatment are neither sufficient to treat this disease, nor prevent late complications in most patients. The most promising therapeutic approach in the treatment of diabetes is the restoring of insulin production. One such method is the transplantation of insulin-producing tissue. However, a lack of available insulin- producing tissue limits such therapeutic approach. Therefore an alternative source of insulin producing cells have to be found to obtain a sufficient amount of safe and efficient insulin producing tissue. Pancreatic stem/progenitor cells could represent such an available alternative source. Despite the evidence...
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Differentiation of adult stem cells into insulin-producing beta cells
Koblas, Tomáš ; Saudek, František (advisor) ; Grim, Miloš (referee) ; Štechová, Kateřina (referee)
Ph.D. Thesis abstract: Diabetes mellitus is a chronic disease characterized by a metabolic disorder in which there is a low level or complete lack of the insulin. Diabetes mellitus type 1 (DM1) is caused by an autoimmune reaction leading to the destruction of the insulin producing beta cells in the pancreas. In consequence, low or non-existent insulin production leads to a complete dependence on exogenous insulin supplementation. DM1 causes serious long-term complications. Although strict control of blood sugar could prevent the onset and development of diabetic complications only 5% of diabetic patients are able to achieve such control. Hence it is evident that the current methods of treatment are neither sufficient to treat this disease, nor prevent late complications in most patients. The most promising therapeutic approach in the treatment of diabetes is the restoring of insulin production. One such method is the transplantation of insulin-producing tissue. However, a lack of available insulin- producing tissue limits such therapeutic approach. Therefore an alternative source of insulin producing cells have to be found to obtain a sufficient amount of safe and efficient insulin producing tissue. Pancreatic stem/progenitor cells could represent such an available alternative source. Despite the evidence...
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