23 research outputs found
The circadian clock protein REVERBα inhibits pulmonary fibrosis development
Pulmonary inflammatory responses lie under circadian control; however, the importance of circadian mechanisms in the underlying fibrotic phenotype is not understood. Here, we identify a striking change to these mechanisms resulting in a gain of amplitude and lack of synchrony within pulmonary fibrotic tissue. These changes result from an infiltration of mesenchymal cells, an important cell type in the pathogenesis of pulmonary fibrosis. Mutation of the core clock protein REVERBα in these cells exacerbated the development of bleomycin-induced fibrosis, whereas mutation of REVERBα in club or myeloid cells had no effect on the bleomycin phenotype. Knockdown of REVERBα revealed regulation of the little-understood transcription factor TBPL1. Both REVERBα and TBPL1 altered integrinβ1 focal-adhesion formation, resulting in increased myofibroblast activation. The translational importance of our findings was established through analysis of 2 human cohorts. In the UK Biobank, circadian strain markers (sleep length, chronotype, and shift work) are associated with pulmonary fibrosis, making them risk factors. In a separate cohort, REVERBα expression was increased in human idiopathic pulmonary fibrosis (IPF) lung tissue. Pharmacological targeting of REVERBα inhibited myofibroblast activation in IPF fibroblasts and collagen secretion in organotypic cultures from IPF patients, thus suggesting that targeting of REVERBα could be a viable therapeutic approach
Polyelectrolyte nanocapsules as paclitaxel delivery system
Mimo wieloletnich prób znalezienia lepszej terapii przeciwnowotworowej, interwencja chirurgiczna i chemioterapia wciąż pozostają najczęściej wykorzystywanymi metodami leczenia tej choroby. W przypadku chemioterapii, skuteczność leczenia znacznie obniża przede wszystkim: 1) cytotoksyczny wpływ chemioterapeutyków na prawidłowe komórki i tkanki, 2) słaba rozpuszczalność wielu leków w roztworach wodnych, 3) inaktywacja leków przez białka osocza oraz 4) niekorzystna biodystrybucja leków w organizmie. W celu przezwyciężenia powyższych problemów zaczęto opracowywać nowoczesne terapie przeciwnowotworowe oparte na wykorzystaniu takich nośników leków, które poprawiłyby ich terapeutyczną skuteczność. Szczególne zainteresowanie wzbudziła tu nanotechnologia oferująca szeroki wybór nanomateriałów, które od lat próbuje się wykorzystać do transportu leków. Obecnie uważa się, iż zastosowanie nanocząstek jako systemu dostarczającego leki przeciwnowotworowe może zwiększyć efektywność transportu chemioterapeutyków i obniżyć ich toksyczny wpływ na zdrowe komórki i tkanki. Wprowadzony do organizmu nanonośnik może być jednak toksyczny, dlatego kluczowym etapem badań takiego nanomateriału, jest potwierdzenie bezpieczeństwa badanych nanocząstek zarówno in vitro jak in vivo.Celem niniejszej pracy była weryfikacja cytotoksyczności uzyskanych nanocząstek oraz ocena ich właściwości jako systemu transportującego leki przeciwnowotworowe. W doświadczeniach użyto nanokapsułek otrzymanych unikatową metodą sekwencyjnej adsorpcji przeciwnie naładowanych polielektrolitów (ang. layer-by-layer) na kroplach emulsyjnych, a jako chemioterapeutyk wykorzystano zamknięty we wnętrzu nanokapsułek paklitaksel (lek wykorzystywanym do leczenia między innymi raka jajników oraz piersi). W przeprowadzonych badaniach wykorzystano różne linie komórek nowotworowych oraz posłużono się różnymi metodami badania przeżywalności komórek jak i poboru nanocząstek. Takie podejście umożliwiło ocenę zarówno toksyczności wolnego nanomateriału jak i jego skuteczności jako nośnika paklitakselu.Despite many decades of research on cancer treatment, surgery and chemotherapy are two widespread methods against this disease. Unfortunately, the clinical application of anticancer drugs is limited by: 1) toxic side effects on normal cell and tissue, 2) poor aqueous solubility of this agents, 3) inactivation of drugs by serum proteins and 4) unfavorable body biodistribution of this agent. To overcome this problems many modern therapies based on different carriers are now on trials. Nanotechnology is especially of interest, because of many types of nanomaterials are used as drug delivery systems. Nowadays nanoparticles are regarded as an effective candidate for solubilization and specific delivery of cytotoxic drugs which decreases side effects on normal cells and tissue. Unfortunately, nanocarriers are often cytotoxic after systematic exposure. Because of that fact crucial step in preclinical is confirmation of nanoparticles in vitro and in vivo safety.The main goals of this studies were to evaluate the cytotoxic effect of nanoparticles and to verify their capacity as a drug delivery system. In this research, nanocapsules were prepared by a sequential adsorption of a opposite charged polyelectrolyte on emulsion core (layer-by-layer technique) and as anticancer drug paclitaxel (medication used to treat a number of types of cancer including ovarian and breast cancer) was used. To evaluate toxicity of polyelectrolyte nanocapsules and examine their potential as anticancer drug nanocarrier different cancer cell line were used. To rich our goal various cell proliferation assays were performed and nanoparticles uptake was examine
Fluorophore localization determines the results of biodistribution of core-shell nanocarriers
INTRODUCTION: Biodistribution of nanocarriers with a structure consisting of core and shell is most often analyzed using methods based on labeling subsequent compartments of nanocarriers. This approach may have serious limitations due to the instability of such complex systems under in vivo conditions. METHODS: The core-shell polyelectrolyte nanocarriers were intravenously administered to healthy BALB/c mice with breast cancer. Next, biodistribution profiles and elimination routes were determined post mortem based on fluorescence measurements performed for isolated blood, tissue homogenates, collected urine, and feces. RESULTS: Despite the surface PEGylation with PLL-g-PEG, multilayer polyelectrolyte nanocarriers undergo rapid degradation after intravenous administration. This process releases the shell components but not free Rhodamine B. Elements of polyelectrolyte shells are removed by hepatobiliary and renal clearance. CONCLUSION: Multilayer polyelectrolyte nanocarriers are prone to rapid degradation after intravenous administration. Fluorophore localization determines the obtained results of biodistribution and elimination routes of core-shell nanomaterials. Therefore, precise and reliable analysis of in vivo stability and biodistribution of nanomaterials composed of several compartments requires nanomaterials labeled within each compartment
Polyaminoacid based core@shell nanocarriers of 5-Fluorouracil : synthesis, properties and theranostics application
Cancer is one of the most important health problems of our population, and one of the common anticancer treatments is chemotherapy. The disadvantages of chemotherapy are related to the drug’s toxic effects, which act on cancer cells and the healthy part of the body. The solution of the problem is drug encapsulation and drug targeting. The present study aimed to develop a novel method of preparing multifunctional 5-Fluorouracil (5-FU) nanocarriers and their in vitro characterization. 5-FU polyaminoacid-based core@shell nanocarriers were formed by encapsulation drug-loaded nanocores with polyaminoacids multilayer shell via layer-by-layer method. The size of prepared nanocarriers ranged between 80–200 nm. Biocompatibility of our nanocarriers as well as activity of the encapsulated drug were confirmed by MTT tests. Moreover, the ability to the real-time observation of developed nanocarriers and drug accumulation inside the target was confirmed by fluorine magnetic resonance imaging ((19)F-MRI)
Bacteriocin BacSp222 and its succinylated forms inhibit proinflammatory activities toward innate immune cells
Purpose: The zoonotic opportunistic pathogen Staphylococcus pseudintermedius 222 produces BacSp222 – an atypical peptide exhibiting the features of a bacteriocin, a virulence factor, and a molecule modulating the host inflammatory reaction. The peptide is secreted in an unmodified form and, additionally, two forms modified posttranslationally by succinylation. This study is a comprehensive report focusing on the proinflammatory properties of such molecules.
Methods: The study was performed on mouse monocyte/macrophage-like and endothelial cell lines as well as human neutrophils. The following peptides were studied: BacSp222, its succinylated forms, the form deprived of formylated methionine, and a reference bacteriocin – nisin. The measurements of the nitric oxide (NO) level, induced NO synthase (iNOS) expression, the profile of secreted cytokines, NF-kappa-B activation, reactive oxygen species (ROS) biosynthesis, and the formation of extracellular traps were conducted to evaluate the proinflammatory activity of the studied peptides.
Results: BacSp222 and its succinylated forms effectively induced NO production and iNOS expression when combined with IFN-gamma in macrophage-like cells. All natural BacSp222 forms used alone or with IFN-gamma stimulated the production of TNF-alpha, MCP-1, and IL-1-alpha, while the co-stimulation with IFN-gamma increased IL-10 and IL-27. Upregulated TNF-alpha secretion observed after BacSp222 exposition resulted from increased expression but not from membrane TNF-alpha proteolysis. In neutrophils, all forms of bacteriocin upregulated IL-8, but did not induce ROS production or NETs formation. In all experiments, the activities of deformylated bacteriocin were lower or unequivocal in comparison to other forms of the peptide.
Conclusion: All naturally secreted forms of BacSp222 exhibit proinflammatory activity against monocyte-macrophage cells and neutrophils, confirming that the biological role of BacSp222 goes beyond bactericidal and cytotoxic effects. The atypical posttranslational modification (succinylation) does not diminish its immunomodulatory activity in contrast to the lower antibacterial potential or cytotoxicity of such modified form established in previous studies
Control of specific/nonspecific protein adsorption : functionalization of polyelectrolyte multilayer films as a potential coating for biosensors
Control of nonspecific/specific protein adsorption is the main goal in the design of novel biomaterials, implants, drug delivery systems, and sensors. The specific functionalization of biomaterials can be achieved by proper surface modification. One of the important strategies is covering the materials with functional coatings. Therefore, our work aimed to functionalize multilayer coating to control nonspecific/specific protein adsorption. The polyelectrolyte coating was formed using a layer-by-layer technique (LbL) with biocompatible polyelectrolytes poly-L-lysine hydrobromide (PLL) and poly-L-glutamic acid (PGA). Nonspecific protein adsorption was minimized/eliminated by pegylation of multilayer films, which was achieved by adsorption of pegylated polycations (PLL-g-PEG). The influence of poly (ethylene glycol) chain length on eliminating nonspecific protein adsorption was confirmed. Moreover, to achieve specific protein adsorption, the multilayer film was also functionalized by immobilization of antibodies via a streptavidin bridge. The functional coatings were tested, and the adsorption of the following proteins confirmed the ability to control nonspecific/specific adsorption: human serum albumin (HSA), fibrinogen (FIB), fetal bovine serum (FBS), carcinoembryonic antigen human (CEA) monitored by quartz crystal microbalance with dissipation (QCM-D). AFM imaging of unmodified and modified multilayer surfaces was also performed. Functional multilayer films are believed to have the potential as a novel platform for biotechnological applications, such as biosensors and nanocarriers for drug delivery systems