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Study of mechanisms influencing inflammatory and neurodegenerative processes and their subsequent treatment in ALS and spinal cord injury
Vargová, Ingrid ; Jendelová, Pavla (advisor) ; Jiruška, Přemysl (referee) ; Balaštík, Martin (referee)
Study of mechanisms influencing inflammatory and neurodegenerative processes and their subsequent treatment in models of ALS and spinal cord injury The mechanisms of neurodegeneration during spinal cord injury (SCI) and amyotrophic lateral sclerosis (ALS) are complex and poorly understood, which is why it's troublesome to counteract them with effective therapies. This thesis explores the pathways of autophagy, endoplasmic reticulum (ER) stress, and the mammalian target of rapamycin (mTOR) pathway that regulates these mechanisms in models of both SCI and ALS. Upregulation of autophagy and the mTOR pathway in an in vivo contusion SCI injury model was confirmed. The mTOR inhibition led to upregulation of autophagy, reduction of inflammation, and recovery in acute SCI. Upregulated autophagy was discovered in the SOD1G93A rat model of ALS. By treating the ALS rats with human mesenchymal stem cells, prolonged survival of the animals and preservation of motor neurons (MNs) possibly occurred through modulation of autophagy. The involvement of the mTOR pathway in the degeneration of MNs was further explored in the context of astrocytes. Pleckstrin homology like domain family A member 3 (PHLDA3), a newly discovered repressor of the mTOR pathway, was found to lead to ER stress if overexpressed in astrocytes...
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Endoplasmic reticulum stress
Červenka, Jakub ; Schierová, Michaela (advisor) ; Horníková, Lenka (referee)
The accumulation of unfolded or misfolded proteins in endoplasmic reticulum (ER) leads to ER stress and the activation of unfolded protein response (UPR). Recent studies show that ER stress or UPR are associated with many diseases such as diabetes, hepatitis type C, prion disease, different kinds of tumors or Alzheimer's, Parkinson's and Huntington's disease and also with physiological processes like cell differentiation. When UPR is activated in yeast Saccharomyces cerevisiae, Ire1 protein oligomerizes, transautophosphorylates and activates itself. After this, Ire1 cleaves HAC1 mRNA to remove an intron. The spliced form of HAC1 mRNA is translated into the Hac1 transcription factor, which induces transcription of genes for chaperones of lumen ER, proteins involved in ERAD, synthesis of lipids etc. The cell uses this to reestablish homeostasis in ER. In mammals, the UPR is more complex and except Ire1 dependent pathway, it comprises Perk and Atf6 pathways, which are missing in yeast. Nevertheless, Perk is activated and regulated by the similar mechanism as Ire1 in S. cerevisiae. In consideration of broad spectrum of methods for genetic manipulation, rapid growth and well annotated genome, the yeast S. cerevisiae is a useful model for study of general mechanisms of UPR in mammals.
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Impact of weight loss in obese subjects on the sensitivity of adipose tissue cells in relation to stress of endoplasmatic reticulum.
Karlická, Michaela ; Rossmeislová, Lenka (advisor) ; Němcová, Vlasta (referee)
Adipocytokines released by the adipose tissue play an important role in the regulation of immune and inflammatory responses. In obesity their production is dysregulated, which is one of the major factors contributing to the onset of a chronic low-grade systemic inflammation representing a risk factor for the progression of other diseases, such as atherosclerosis or type-2 diabetes. The main goal of this thesis was to analyze the secretion of selected adipocytokines (adiponectin, IL6 and MCP1) by in-vitro differentiated adipocytes, isolated from the adipose tissue prior to and after a dietary intervention, and this under basal conditions and during stimulated lipolysis. In case of adiponectin, the secretion of its isoforms was analyzed too. The concentration of adiponectin, IL6 and MCP1 was determined by the ELISA method, the Western Blot method was used to determine the distribution of the adiponectin isoforms. The thesis also concentrates on the gene expression of ATF3, ATF4 and HSPA5, factors engaged in the ER stress in the course of the differentiation of adipocytes. The changes in the gene expression were measured by the quantitative Real Time PCR method. At the same time the development of the endoplasmic reticulum (ER) in the course of adipogenesis was monitored by indirect...
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Endoplasmic reticulum stress
Červenka, Jakub ; Schierová, Michaela (advisor) ; Horníková, Lenka (referee)
The accumulation of unfolded or misfolded proteins in endoplasmic reticulum (ER) leads to ER stress and the activation of unfolded protein response (UPR). Recent studies show that ER stress or UPR are associated with many diseases such as diabetes, hepatitis type C, prion disease, different kinds of tumors or Alzheimer's, Parkinson's and Huntington's disease and also with physiological processes like cell differentiation. When UPR is activated in yeast Saccharomyces cerevisiae, Ire1 protein oligomerizes, transautophosphorylates and activates itself. After this, Ire1 cleaves HAC1 mRNA to remove an intron. The spliced form of HAC1 mRNA is translated into the Hac1 transcription factor, which induces transcription of genes for chaperones of lumen ER, proteins involved in ERAD, synthesis of lipids etc. The cell uses this to reestablish homeostasis in ER. In mammals, the UPR is more complex and except Ire1 dependent pathway, it comprises Perk and Atf6 pathways, which are missing in yeast. Nevertheless, Perk is activated and regulated by the similar mechanism as Ire1 in S. cerevisiae. In consideration of broad spectrum of methods for genetic manipulation, rapid growth and well annotated genome, the yeast S. cerevisiae is a useful model for study of general mechanisms of UPR in mammals.
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