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Lysosome Alterations in the Human Epithelial Cell Line HaCaT and Skin Specimens: Relevance to Psoriasis
Get PDFDespite the constantly updated knowledge regarding the alterations occurring in the
cells of patients with psoriasis, the status and the role of the lysosome, a control center of cell
metabolism, remain to be elucidated. The architecture of the epidermis is largely regulated
by the action of lysosomes, possibly activating signaling pathways in the cellular crosstalk of
keratinocytes—epidermal cells—with infiltrating immune cells. Thus, in the present study, lysosome
alterations were examined in vitro and in situ using a two-dimensional (2D) keratinocyte model of
HaCaT cells with “psoriasis-like” inflammation and skin specimens, respectively. Specific fluorescence
and immunohistochemical staining showed an augmented level of acidic organelles in response to
keratinocyte activation (mimicking a psoriatic condition while maintaining the membrane integrity of
these structures) as compared with the control, similar to that seen in skin samples taken from patients.
Interestingly, patients with the most pronounced PASI (Psoriasis Area and Severity Index), BSA
(Body Surface Area), and DLQI (Dermatology Life Quality Index) scores su�ered a high incidence of
positive lysosomal-associated membrane protein 1 (LAMP1) expression. Moreover, it was found that
the gene deregulation pattern was comparable in lesioned (PP) and non-lesioned (PN) patient-derived
skin tissue, which may indicate that these alterations occur prior to the onset of the characteristic
phenotype of the disease. Changes in the activity of genes encoding the microphthalmia family
(MiT family) of transcription factors and mammalian target of rapamycin complex 1 (MTORC1) were
also observed in the in vitro psoriasis model, indicating that the biogenesis pathway of this arm is
inhibited. Interestingly, in contrast to the keratinocytes of HaCaT with “psoriasis-like” inflammation,
LAMP1 was up-regulated in both PP and PN skin, which can be a potential sign of an alternative
mechanism of lysosome formation. Defining the molecular profile of psoriasis in the context of “the
awesome lysosome” is not only interesting, but also desired; therefore, it is believed that this paper
will serve to encourage other researchers to conduct further studies on this subject
Anticancer agents found in environment affect Daphnia at population, individual and molecular levels
Get PDFPharmaceuticals are used in medical treatment on a large scale and as a waste contaminate freshwater ecosystems. Growing amount of so-called civilization diseases, such as different type of cancer, significantly contribute to this form of pollution. The aim of the present study was to determine how the exposure to chemotherapeutics: cyclophosphamide (CP) and cisplatin (CDDP), at detected in environment concentrations, influence proteome profile, life history and population parameters of naturally setting surface waters Daphnia pulex and Daphnia pulicaria. The parameters important for crustaceans, survivorship and population growth rate, were importantly decreased by CDDP treatment but not influenced by CP. On the contrary, the individual growth rate was affected only by CP and exclusively in the case of D. pulicaria. In both clones treated with CP or CDDP, decreased number of eggs was observed. Interestingly, Daphnia males were less sensitive to tested chemotherapeutic than females. Proteome profile revealed that tested anticancer pharmaceuticals modified expression of some proteins involved in Daphnia metabolism. Moreover, males exposed to CDDP showed increased level of enzymes participating in DNA repair. Summing up, the contaminating environment chemotherapeutics reduced fitness of naturally occurring Daphnia species. In consequence this may affect functioning of the aquatic food webs
Mechanisms controlling chromatin structure
Get PDFGenomic DNA is highly packaged in eukaryotic cells and occurs in the form of nucleoprotein complex called chromatin. Although high DNA
compaction allows to store large amount of genomic information in the cell nuclei, it also restricts the access to DNA regulatory sequences.
Therefore, to overcome this issue, chromatin must be subjected to various alterations which are dependent on few interrelated factors: DNA
modification, histones variants and modifications, ncRNA, chromatin remodeling complexes and chromatin architecture in nuclei. They allow
to multilayer regulation of fragile balance between transcriptionally active euchromatin and inactive heterochromatin. The newest research
describe new chromatin elements, e.g. half nucleosomes, bivalent chromatin marker and pointed to few intermediate states between euchromatin and heterochromatin. Variety and remarkable amount of chromatin modifications require existence of multiprotein complexes reading,
editing and integrating genomic information. Some of them are able to remodel nucleosomes in order to control access to particular DNA
sequence. Due to the complexity of chromatin structure regulation studies describing these mechanisms are fundamental to understanding
the eukaryotes life
Tunneling nanotube-mediated intercellular vesicle and protein transfer in the stroma-provided imatinib resistance in chronic myeloid leukemia cells
Get PDFIntercellular communication within the bone marrow niche significantly promotes leukemogenesis and provides
protection of leukemic cells from therapy. Secreted factors, intercellular transfer of mitochondria and the
receptor–ligand interactions have been shown as mediators of this protection. Here we report that tunneling
nanotubes (TNTs)—long, thin membranous structures, which have been identified as a novel mode of intercellular
cross-talk—are formed in the presence of stroma and mediate transfer of cellular vesicles from stroma to leukemic
cells. Importantly, transmission of vesicles via TNTs from stromal cells increases resistance of leukemic cells to the
tyrosine kinase inhibitor, imatinib. Using correlative light-electron microscopy and electron tomography we show that
stromal TNTs contain vesicles, provide membrane continuity with the cell bodies and can be open-ended. Moreover,
trans-SILAC studies to reveal the non-autonomous proteome showed that specific sets of proteins are transferred
together with cellular vesicles from stromal to leukemic cells, with a potential role in survival and adaptation.
Altogether, our findings provide evidence for the biological role of the TNT-mediated vesicle exchange between
stromal and leukemic cells, implicating the direct vesicle and protein transfer in the stroma-provided protection of
leukemic cells
Rational drug-design approach supported with thermodynamic studies — a peptide leader for the efficient bi-substrate inhibitor of protein kinase CK2
Get PDFNumerous inhibitors of protein kinases act on the basis of competition, targeting the ATP binding site. In this work, we present a procedure of rational design of a bi-substrate inhibitor, complemented with biophysical assays. The inhibitors of this type are commonly engineered by combining ligands carrying an ATP-like part with a peptide or peptide-mimicking fragment that determines specificity. Approach presented in this paper led to generation of a specific system for independent screening for efficient ligands and peptides, by means of thermodynamic measurements, that assessed the ability of the identified ligand and peptide to combine into a bi-substrate inhibitor. The catalytic subunit of human protein kinase CK2 was used as the model target. Peptide sequence was optimized using peptide libraries [KGDE]-[DE]-[ST]-[DE]3–4-NH2, originated from the consensus CK2 sequence. We identified KESEEE-NH2 peptide as the most promising one, whose binding affinity is substantially higher than that of the reference RRRDDDSDDD peptide. We assessed its potency to form an efficient bisubstrate
inhibitor using tetrabromobenzotriazole (TBBt) as the model ATP-competitive inhibitor. The formation of ternary complex was monitored using Differential Scanning Fluorimetry (DSF), Microscale Thermophoresis (MST) and Isothermal Titration Calorimetry (ITC)
The Ability of Lytic Staphylococcal Podovirus vB_SauP_phiAGO1.3 to Coexist in Equilibrium With Its Host Facilitates the Selection of Host Mutants of Attenuated Virulence but Does Not Preclude the Phage Antistaphylococcal Activity in a Nematode Infection Model
Get PDFPhage vB_SauP_phiAGO1.3 (phiAGO1.3) is a polyvalent Staphylococcus lytic podovirus with a 17.6-kb genome (Gozdek et al., 2018). It can infect most of the Staphylococcus aureus human isolates of dominant clonal complexes. We show that a major factor contributing to the wide host range of phiAGO1.3 is a lack or sparcity of target sites for certain restriction-modification systems of types I and II in its genome. Phage phiAGO1.3 requires for adsorption β-O-GlcNAcylated cell wall teichoic acid, which is also essential for the expression of methicillin resistance. Under certain conditions an exposure of S. aureus to phiAGO1.3 can lead to the establishment of a mixed population in which the bacteria and phages remain in equilibrium over multiple generations. This is reminiscent of the so called phage carrier state enabling the co-existence of phage-resistant and phage-sensitive cells supporting a continuous growth of the bacterial and phage populations. The stable co-existence of bacteria and phage favors the emergence of phage-resistant variants of the bacterium. All phiAGO1.3-resistant cells isolated from the phage-carrier-state cultures contained a mutation inactivating the two-component regulatory system ArlRS, essential for efficient expression of numerous S. aureus virulence-associated traits. Moreover, the mutants were unaffected in their susceptibility to infection with an unrelated, polyvalent S. aureus phage of the genus Kayvirus. The ability of phiAGO1.3 to establish phage-carrier-state cultures did not preclude its antistaphylococcal activity in vivo in an S. aureus nematode infection model. Taken
together our results suggest that phiAGO1.3 could be suitable for the therapeutic application in humans and animals, alone or in cocktails with Kayvirus phages. It might be especially useful in the treatment of infections with the majority of methicillin-resistant S. aureus strains
Dose-adjusted and dose/kg-adjusted concentrations of mycophenolic acid precursors reflect metabolic ratios of their metabolites in contrast with tacrolimus and cyclosporine
Get PDFNew Insight on Water Status in Germinating Brassica napus Seeds in Relation to Priming-Improved Germination
Get PDFSeed priming is a pre-sowing method successfully used to improve seed germination. Since water plays a crucial role in germination, the aim of this study was to investigate the relationship between better germination performances of osmoprimed Brassica napus seeds and seed water status during germination. To achieve this goal, a combination of different kinds of approaches was used, including nuclear magnetic resonance (NMR) spectroscopy, TEM, and SEM as well as semi-quantitative PCR (semi-qPCR). The results of this study showed that osmopriming enhanced the kinetics of water uptake and the total amount of absorbed water during both the early imbibition stage and in the later phases of seed germination. The spin–spin relaxation time (T2) measurement suggests that osmopriming causes faster water penetration into the seed and more efficient tissue hydration. Moreover, factors potentially affecting water relations in germinating primed seeds were also identified. It was shown that osmopriming (i) changes the microstructural features of the seed coat, e.g., leads to the formation of microcracks, (ii) alters the internal structure of the seed by the induction of additional void spaces in the seed, (iii) increases cotyledons cells vacuolization, and (iv) modifies the expression pattern of aquaporin genes
Effect of two distinct patches of Myriophyllum species on downstream turbulence in a natural river
Get PDFVelocity profiles upstream and downstream of two aquatic plant species that are similar in morphology but differ in patch structures were measured in a natural river. Turbulence statistics were analyzed after thorough data filtering. In the wake of the M. alterniflorum, which was a slender, 0.3 m wide and 1.2 m long patch of aspect ratio 1:4, there were distinctive peaks in both, turbulence intensity and turbulent kinetic energy, which indicated increased lateral mixing. In contrast to the M. alterniflorum, turbulence statistics in the wake of the M. spicatum, which was the larger, 2 m wide and 2.4 m long patch of aspect ratio 1:1.5, indicated increased lateral shear of a greater magnitude. The turbulent kinetic energy was diminished in the closest layer to the bed downstream the both plants, although, in the case of M. alterniflorum, the observed values were similar to those upstream. The occurrence of the mixing layer below the height of M. spicatum was visible in the power spectral density plot. In both cases, ejections in the wake diminished in favor of other coherent structures. The shape and configuration of a patch are decisive factors governing the occurrence of flow instabilities downstream of the patch
Investigation of Sediment-Rich Glacial Meltwater Plumes Using a High-Resolution Multispectral Sensor Mounted on an Unmanned Aerial Vehicle
Get PDFA Parrot Sequoia+ multispectral camera on a Parrot Bluegrass drone registered in four spectral bands (green, red, red edge (RE), and near-infrared (NIR)) to identify glacial outflow zones and determined the meltwater turbidity values in waters in front of the following Antarctic glaciers: Ecology, Dera Icefall, Zalewski, and Krak on King George Island, Southern Shetlands was used. This process was supported by a Red-Green-Blue (RGB) colour model from a Zenmuse X5 camera on an Inspire 2 quadcopter drone. Additional surface water turbidity measurements were carried out using a Yellow Springs Instruments (YSI) sonde EXO2. From this research, it was apparent that for mapping low-turbidity and medium-turbidity waters (<70 formazinenephelometricunits (FNU)), a red spectral band should be used, since it is insensitive to possible surface ice phenomena and registers the presence of both red and white sediments. High-turbidity plumes with elevated FNU values should be identified through the NIR band. Strong correlation coefficients between the reflectance at particular bands and FNU readings (RGreen = 0.85, RRed = 0.85, REdge = 0.84, and RNIR = 0.83) are shown that multispectral mapping using Unmanned Aerial Vehicles (UAVs) can be successfully usedeven in the unfavourable weather conditions and harsh climate of Antarctica. Lastly, the movement of water masses in Admiralty Bay is briefly discussed and supported by the results from EXO2 measurements