http://hdl.handle.net/11089/1 Wed, 14 Oct 2026 04:20:43 GMT 2026-10-14T04:20:43Z https://dspace.uni.lodz.pl:443/xmlui/bitstream/id/4322885a-3abf-4f62-88fd-762733949669/ http://hdl.handle.net/11089/1 http://hdl.handle.net/11089/59465 Charakterystyka potencjału przeciwnowotworowego kwasu roburowego Gielecińska, Adrianna Roburic acid (RA), a tetracyclic triterpenoid, has demonstrated antiproliferative and anti-inflammatory properties, although its cellular mechanisms remain incompletely understood. This doctoral research aimed to characterize the anticancer activity of RA, with particular emphasis on colorectal cancer (CRC), and to identify the mechanisms underlying its effects on cell proliferation and survival. RA activity was initially evaluated in human cancer and non-malignant cell lines, followed by mechanistic studies in DLD-1, HCT-116, and HT-29 cells. RA inhibited cancer cell growth in a concentration- and time-dependent manner, with CRC cells exhibiting relatively high sensitivity. Reduced DNA synthesis, clonogenic capacity, and proliferation markers, together with G0/G1 cell cycle arrest, indicated a predominantly cytostatic effect. RA also attenuated TNF-α-induced NF-κB transcriptional activity and decreased mitochondrial membrane potential without inducing oxidative stress or DNA damage. Although apoptotic features and caspase-9 activation were detected under certain conditions, pharmacological inhibition of apoptosis, necroptosis, or ferroptosis did not reverse RA-induced growth inhibition. Furthermore, RA did not induce cellular senescence. Changes in P53 and P21 expression and subcellular localization suggested cell line-dependent modulation of cell cycle regulatory mechanisms. Complementary in silico analyses identified potential molecular targets, including CAII, CES1, EGFR, and PLA2G2A. Overall, RA primarily suppresses CRC cell proliferation through cytostatic mechanisms, while mitochondrial dysfunction and apoptosis represent secondary, context-dependent responses. These findings support further investigation of RA as a potential anticancer lead compound. Thu, 01 Jan 2026 00:00:00 GMT http://hdl.handle.net/11089/59465 2026-01-01T00:00:00Z http://hdl.handle.net/11089/59451 Effects of polyethylene nanoparticles on the haemostatic system in vitro: insights into coagulation cascade and fibrinolysis. Dataset. Michaś, Karolina; Liudvytska, Oleksandra; Kołodziejczyk-Czepas, Joanna Activity of Xa factor dataset. Amidolitic activity of thrombin dataset. CFF assay dataset. Clotting times dataset. Fibrinogen polymerization (fibrinogen and thrombin treated) dataset. SDS-PAGE based analysis of the plasmin-metiated fibrinogen degradation (dataset and gel images after electrophoresis). SEM images. tPa and uPa inducted plasmin activity dataset. Thu, 01 Jan 2026 00:00:00 GMT http://hdl.handle.net/11089/59451 2026-01-01T00:00:00Z http://hdl.handle.net/11089/59430 Role of Apolipoprotein E in the Pathogenesis of Prion Diseases Lizińczyk, Anita Prion diseases (prionoses) are a group of fatal, neurodegenerative disorders, which affect humans and certain mammalian species. Underlaying the prion disease pathogenesis is accumulation of the disease-specific PrPSc (Sc-scrapie). PrPSc is an infectious and toxic conformer of the cellular prion protein PrPC. Key features of PrPSc include proteolytic resistance, susceptibility to oligomerization, and ability to self-replicate by binding to PrPC and altering its 𝛼�����-helix-rich conformation into the image of its own secondary structure, dominated by increased β-sheet content. Excessive accumulation of PrPSc on the cell surface and within the endolysosomal compartment leads to neurodegeneration and ultimately death of PrPSc-replicating neurons. Appearance and accumulation of PrPSc, followed by neuronal demise activates neuroinflammatory response from microglia and astrocytes, which contributes importantly to neurodegeneration in prionoses. Apolipoprotein (apo) E is a lipid transporting protein, which is implicated in the pathogenesis of several neurodegenerative disorders including Alzheimer’s disease, primary tauopathies, 𝛼�����-synucleinopathy, and age-related macular degeneration. In these entities the APOE allele polymorphism is a well-recognized factor affecting the risk of disease occurrence and (or) the rate of pathology progression. Three apoE isoforms encoded by respective APOE alleles 𝜀�����2, 𝜀�����3, and 𝜀�����4, differentially engage several biological mechanisms, which are critically involved in neurodegeneration. These include binding apoE receptors, influencing formation and trafficking of endolysosomal vesicles, synaptic plasticity and synaptic protein expression, modulating neuronal transcriptome, interacting with disease-specific misfolded proteins and regulating neuroinflammatory response. Although apoE has been established as a critical element in several neurodegenerative diseases its role in the pathobiology of prion diseases remains unknown. To elucidate contribution of apoE to prion pathogenesis a series of experiments were conducted in B6 wild type mice and apoE transgenic model mice, which were infected with 22L mouse adapted scrapie strain. B622L mice showed significantly increased brain apoE level compared to the B6 control mice and this increase was associated with marked cell-type shift in the apoE expression. B622L mice featured reduced apoE expression in reactive astrocytes, which under physiological conditions produce apoE-containing lipoparticles, while de-repression of the apoE expression was found in reactive microglia, which in resting (or surveilling) state do not express apoE. In the succeeding experiment Apoe-/- mice were infected with the 22L prion strain, resulting in significantly reduced disease incubation time, accelerated rate of neurological symptoms progression, and increased burden of brain pathology compared to B622L mice. Apoe-/-22L mice featured exacerbated neuroinflammatory response produced by reactive astrocytes and neurodegenerative phenotype microglia (MGnD), with the later additionally showing reduced ability to phagocyte damaged neurons and PrPSc. In the subsequent study mice with bi-allelic, targeted replacement (TR) of the murine Apoe gene for human APOE 𝜀�����2, 𝜀�����3, and 𝜀�����4 alleles were infected with prions. 𝜀�����4/𝜀�����422L mice showed the shortest disease incubation time, the fastest tempo of neurological symptoms progression, and the highest level of prion-specific neuropathological metrics. 𝜀�����2/𝜀�����222L mice were significantly less affected than 𝜀�����4/𝜀�����422L mice but nonetheless performed significantly worse compared to 𝜀�����3/𝜀�����322L mice. Two 𝜀�����4-allele attributable disease mechanisms, which explain exacerbated disease course in 𝜀�����4/𝜀�����422L mice were identified: increased conversion and accumulation of PrPSc and worsened prion-associated neuroinflammation. It also was determined that 𝜀�����2 allele independently increases prion-related inflammatory response, rendering the disease outcome worse relative to the 𝜀�����3 allele. Collectively, the work presented in this dissertation demonstrates involvement of apoE in several mechanisms related to prion pathology including conversion and accumulation of PrPSc, regulating inflammatory response of astrocytes and microglia, and modulating microglia phagocytosis of neuronal remnants and PrPSc. Furthermore, findings from APOE-TR mice suggests both 𝜀�����4 and 𝜀�����2 alleles can be disadvantageous determinants in prion pathology. Thu, 01 Jan 2026 00:00:00 GMT http://hdl.handle.net/11089/59430 2026-01-01T00:00:00Z http://hdl.handle.net/11089/59289 Udział olejku eterycznego z Thymus vulgaris L. w łagodzeniu stresu wywołanego kadmem w komórkach merystemów korzeniowych Vicia faba L. var. minor Gocek-Szczurtek, Natalia Wobec narastającego skażenia środowiska kadmem (Cd) celem badań była ocena 24-godzinnego wpływu 175 μM CdCl₂ na funkcjonowanie merystemów korzeni zarodkowych Vicia faba L. var. minor oraz określenie ochronnego działania olejku tymiankowego (TO; 0,03%). Ekspozycja na Cd prowadziła do jego znacznej akumulacji w tkankach, nadprodukcji reaktywnych form tlenu (RFT), nasilenia peroksydacji lipidów i uszkodzeń DNA, mimo aktywacji enzymatycznych i nieenzymatycznych mechanizmów antyoksydacyjnych oraz metabolizmu tiolowego. Towarzyszyły temu zmiany ultrastrukturalne organelli, aktywacja szlaku MAPK oraz przeprogramowanie epigenetyczne obejmujące wzrost metylacji DNA i zmiany modyfikacji histonów, a także zaburzenia replikacji i transkrypcji. Spadek zawartości CDKA i CycB, nieprawidłowa fosforylacja histonu H3 oraz dezorganizacja mikrotubul i filamentów aktynowych prowadziły do zahamowania proliferacji komórek merystematycznych i wzrostu korzeni. TO stosowany samodzielnie nie destabilizował struktury ani funkcji komórek, a w warunkach ekspozycji na Cd częściowo ograniczał jego akumulację i łagodził skutki toksyczności. Przy jednoczesnym zastosowaniu Cd i TO obserwowano ograniczenie akumulacji RFT, wzmocnienie mechanizmów antyoksydacyjnych oraz mniejsze nasilenie peroksydacji lipidów i uszkodzeń DNA. TO sprzyjał zachowaniu integralności ultrastrukturalnej komórek oraz ograniczał indukowane przez Cd zaburzenia szlaku MAPK i zmiany epigenetyczne, utrzymując transkrypcję i replikację bliżej poziomu kontrolnego. Przeciwdziałał także dezorganizacji cytoszkieletu i aparatu mitotycznego, sprzyjając zachowaniu proliferacji komórek merystematycznych i wzrostu korzeni. Opracowanie i adaptacja metody iPOND do materiału roślinnego rozszerzyły możliwości przyszłej analizy białek związanych z nowo syntetyzowanym DNA. Wyniki wskazują, że TO działa wielokierunkowo i może stanowić naturalny czynnik wspierający ochronę roślin przed stresem kadmowym.; In the context of increasing environmental cadmium (Cd) contamination, this study aimed to evaluate the effects of 24 h exposure to 175 μM CdCl₂ on root meristems of Vicia faba L. var. minor and to assess the protective effects of thyme essential oil (TO; 0.03%). Cd exposure caused substantial metal accumulation, reactive oxygen species (ROS) overproduction, increased lipid peroxidation, and DNA damage, despite activation of antioxidant mechanisms and thiol metabolism. These effects were accompanied by organelle ultrastructural alterations, MAPK activation, epigenetic reprogramming involving increased DNA methylation and altered histone modifications, and disturbances in replication and transcription. Reduced CDKA and CycB levels, abnormal histone H3 phosphorylation, and disorganization of microtubules and actin filaments contributed to inhibited meristematic cell proliferation and root growth. TO alone did not destabilize cellular structure or function, while in the presence of Cd it partially limited metal accumulation and alleviated its toxic effects. During simultaneous exposure to Cd and TO, reduced ROS accumulation, enhanced antioxidant responses, and lower lipid peroxidation and DNA damage were observed. TO also promoted preservation of cellular ultrastructure and attenuated Cd-induced disturbances in MAPK signaling and epigenetic regulation, maintaining transcription and replication closer to control levels. It additionally counteracted disorganization of the cytoskeleton and mitotic apparatus, thereby supporting meristematic cell proliferation and root growth. Adaptation of the iPOND method to plant material expanded opportunities for future analysis of proteins associated with newly synthesized DNA. Overall, TO exerted multifaceted protective effects and may support plant protection against cadmium stress. Thu, 01 Jan 2026 00:00:00 GMT http://hdl.handle.net/11089/59289 2026-01-01T00:00:00Z