Spinal cord injuries have devastating consequences for humans, as mammalian neurons of the central nervous system (CNS) cannot regenerate. In the peripheral nervous system (PNS), however, neurons may regenerate to restore lost function following injury. While mammalian CNS tissue softens after injury, how PNS tissue mechanics changes in response to mechanical trauma is currently poorly understood. Here we characterised mechanical rat nerve tissue properties before and after in vivo crush and transection injuries using atomic force microscopy-based indentation measurements. Unlike CNS tissue, PNS tissue significantly stiffened after both types of tissue damage. This nerve tissue stiffening strongly correlated with an increase in collagen I levels. Schwann cells, which crucially support PNS regeneration, became more motile and proliferative on stiffer substrates in vitro, suggesting that changes in tissue stiffness may play a key role in facilitating or impeding nervous system regeneration.

• Klíčová slova
• Crush injury, Nerve compartments, Nerve injury, Nerve stiffness, Schwann cells, Tissue mechanics,
• MeSH
• axony fyziologie   MeSH
• centrální nervový systém MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• nervová tkáň * MeSH
• neurony MeSH
• poranění míchy * MeSH
• regenerace nervu fyziologie   MeSH
• savci MeSH
• Schwannovy buňky fyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Design, controlled synthesis, physico-chemical and biological characteristics of novel well-defined biodegradable star-shaped copolymers intended for advanced drug delivery is described. These new biocompatible star copolymers were synthesised by grafting monodispersed semitelechelic linear (sL) N-(2-hydroxypropyl)methacrylamide copolymers onto a 2,2-bis(hydroxymethyl)propionic acid (bisMPA)-based polyester dendritic core of various structures. The hydrodynamic diameter of the star copolymer biomaterials can be tuned from 13 to 31 nm and could be adjusted to a given purpose by proper selection of the bisMPA dendritic core type and generation and by considering the sL copolymer molecular weight and polymer-to-core molar ratio. The hydrolytic degradation was proved for both the star copolymers containing either dendron or dendrimer core, showing the spontaneous hydrolysis in duration of few weeks. Finally, it was shown that the therapy with the biodegradable star conjugate with attached doxorubicin strongly suppresses the tumour growth in mice and is fully curative in most of the treated animals at dose corresponding approximately to one fourth of maximum tolerated dose (MTD) value. Both new biodegradable systems show superior efficacy and tumour accumulation over the first generation of star copolymers containing non-degradable PAMAM core.

• Klíčová slova
• Cancer, Doxorubicin, Drug delivery, HPMA, Star-like polymers, bisMPA,
• MeSH
• akrylamidy MeSH
• biokompatibilní materiály * MeSH
• doxorubicin MeSH
• léčivé přípravky * MeSH
• methakryláty MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nosiče léků MeSH
• polymery MeSH
• systémy cílené aplikace léků MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• akrylamidy MeSH
• biokompatibilní materiály * MeSH
• doxorubicin MeSH
• hydroxypropyl methacrylate MeSH Prohlížeč
• léčivé přípravky * MeSH
• methakryláty MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• nosiče léků MeSH
• polymery MeSH

Various design and fabrication strategies of carrier-based drug delivery systems have been quickly established and applied for cancer therapy in recent years. These systems contribute greatly to current cancer treatments but further development needs to be made to eliminate obstacles such as low drug loading capacity and severe side effects. To achieve better drug delivery, we propose an innovative strategy for the construction of easy manufactured drug self-delivery systems based on molecular structures, which can be used for the co-delivery of curcuminoids and all the nitrogen-containing derivatives of camptothecin for better targeted cancer therapy with minimized side effects. The formation mechanism investigation demonstrates that the rigid planar structures of camptothecin derivatives and curcuminoids with relevant leaving hydrogens make it possible for them to be assembled into nanoparticles under suitable conditions. These nanoparticles show stabilized particle sizes (100 nm) under various conditions and tunable surface charges which increase from around -10 mV in a normal physiological condition (pH 7.4) to +40 mV under acidic tumor environments. In addition, in vivo mice experiments have demonstrated that, compared to irinotecan (a derivative of camptothecin) itself, the co-delivered irinotecan curcumin nanoparticles exhibited significantly enhanced lung and gallbladder targeting, improved macrophage-clearance escape and ameliorated colorectal cancer treatment with an eradication of life-threatening diarrhea, bringing hope for better targeted chemotherapy and clinical translation. Lastly, the strategy of structure based design of drug self-delivery systems may inspire more research and discoveries of similar self-delivered nano systems for wider pharmaceutical applications.

• Klíčová slova
• Charge conversion, Curcumin, Diarrhea, Irinotecan, Self-delivery, Targeting therapy,
• MeSH
• antitumorózní látky * terapeutické užití   MeSH
• kamptothecin MeSH
• léčivé přípravky * MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory * farmakoterapie   MeSH
• nanočástice * MeSH
• systémy cílené aplikace léků * MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antitumorózní látky * MeSH
• kamptothecin MeSH
• léčivé přípravky * MeSH

Myeloid immune cells promote inflammation and fibrosis in chronic liver diseases. Drug delivery systems, such as polymers, liposomes and microbubbles, efficiently target myeloid cells in healthy liver, but their targeting properties in hepatic fibrosis remain elusive. We therefore studied the biodistribution of three intravenously injected carrier material, i.e. 10 nm poly(N-(2-hydroxypropyl)methacrylamide) polymers, 100 nm PEGylated liposomes and 2000 nm poly(butyl cyanoacrylate) microbubbles, in two fibrosis models in immunocompetent mice. While whole-body imaging confirmed preferential hepatic uptake even after induction of liver fibrosis, flow cytometry and immunofluorescence analysis revealed markedly decreased carrier uptake by liver macrophage subsets in fibrosis, particularly for microbubbles and polymers. Importantly, carrier uptake co-localized with immune infiltrates in fibrotic livers, corroborating the intrinsic ability of the carriers to target myeloid cells in areas of inflammation. Of the tested carrier systems liposomes had the highest uptake efficiency among hepatic myeloid cells, but the lowest specificity for cellular subsets. Hepatic fibrosis affected carrier uptake in liver and partially in spleen, but not in other tissues (blood, bone marrow, lung, kidney). In conclusion, while drug carrier systems target distinct myeloid cell populations in diseased and healthy livers, hepatic fibrosis profoundly affects their targeting efficiency, supporting the need to adapt nanomedicine-based approaches in chronic liver disease.

• Klíčová slova
• Liposomes, Liver fibrosis, Macrophages, Microbubbles, Nanomedicine, Polymers, Targeted delivery,
• MeSH
• fluorescenční mikroskopie MeSH
• imunohistochemie MeSH
• jaterní cirhóza metabolismus   MeSH
• liposomy chemie   MeSH
• lymfocyty metabolismus   MeSH
• makrofágy metabolismus   MeSH
• mikrobubliny MeSH
• myši MeSH
• nanomedicína MeSH
• polymery chemie   MeSH
• průtoková cytometrie MeSH
• rentgenová mikrotomografie MeSH
• systémy cílené aplikace léků MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• liposomy MeSH
• polymery MeSH

The mechanoregulated proteins YAP/TAZ are involved in the adipogenic/osteogenic switch of mesenchymal stem cells (MSCs). MSC fate decision can be unbalanced by controlling substrate mechanics, in turn altering the transmission of tension through cell cytoskeleton. MSCs have been proposed for orthopedic and reconstructive surgery applications. Thus, a tight control of their adipogenic potential is required in order to avoid their drifting towards fat tissue. Substrate mechanics has been shown to drive MSC commitment and to regulate YAP/TAZ protein shuttling and turnover. The mechanism by which YAP/TAZ co-transcriptional activity is mechanically regulated during MSC fate acquisition is still debated. Here, we design few bioengineering tools suited to disentangle the contribution of mechanical from biological stimuli to MSC adipogenesis. We demonstrate that the mechanical repression of YAP happens through its phosphorylation, is purely mediated by cell spreading downstream of substrate mechanics as dictated by dimensionality. YAP repression is sufficient to prompt MSC adipogenesis, regardless of a permissive biological environment, TEAD nuclear presence or focal adhesion stabilization. Finally, by harnessing the potential of YAP mechanical regulation, we propose a practical example of the exploitation of adipogenic transdifferentiation in tumors.

• Klíčová slova
• Adipogenesis, Biocompatible hydrogels, Cell micropatterning, Cell-matrix interaction, Mechanobiology, Mechanosensing, Mesenchymal stem cells, YAP,
• MeSH
• adaptorové proteiny signální transdukční metabolismus   MeSH
• adipogeneze * MeSH
• aktiny metabolismus   MeSH
• buněčné jádro metabolismus   MeSH
• extracelulární matrix metabolismus   MeSH
• fokální adheze metabolismus   MeSH
• fosforylace MeSH
• genetická transkripce MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• pohyb buněk * MeSH
• přeprogramování buněk MeSH
• proliferace buněk MeSH
• signální proteiny YAP MeSH
• transkripční faktory metabolismus   MeSH
• tuková tkáň cytologie   MeSH
• tukové buňky metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• aktiny MeSH
• signální proteiny YAP MeSH
• transkripční faktory MeSH
• YAP1 protein, human MeSH Prohlížeč

Organic triplet-triplet annihilation upconversion (TTA-UC) nanoparticles have emerged as exciting therapeutic agents and imaging probes in recent years due to their unique chemical and optical properties such as outstanding biocompatibility and low power excitation density. In this review, we focus on the latest breakthroughs in such new version of upconversion nanoparticle, including their design, preparation, and applications. First, we will discuss the key principles and design concept of these organic-based photon upconversion in regard to the methods of selection of the related triplet TTA dye pairs (photosensitizer and emitter). Then, we will discuss the recent approaches s to construct TTA-UCNPs including silica TTA-UCNPs, lipid-coated TTA-UCNPs, polymer encapsulated TTA-UCNPs, nano-droplet TTA-UCNPs and metal-organic frameworks (MOFs) constructed TTA-UCNPs. In addition, the applications of TTA-UCNPs will be discussed. Finally, we will discuss the challenges posed by current TTA-UCNP development.

• Klíčová slova
• And cancer therapy, Bioimaging, Nanoparticles, Photo-targeting, Triplet-triplet annihilation upconversion,
• MeSH
• diagnostické zobrazování metody   MeSH
• molekulární struktura MeSH
• nanočástice chemie   MeSH
• oxid křemičitý chemie   MeSH
• polymery chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• oxid křemičitý MeSH
• polymery MeSH

The blocking of specific protein-protein interactions using nanoparticles is an emerging alternative to small molecule-based therapeutic interventions. However, the nanoparticles designed as "artificial proteins" generally require modification of their surface with (bio)organic molecules and/or polymers to ensure their selectivity and specificity of action. Here, we show that nanosized diamond crystals (nanodiamonds, NDs) without any synthetically installed (bio)organic interface enable the specific and efficient targeting of the family of extracellular signalling molecules known as fibroblast growth factors (FGFs). We found that low nanomolar solutions of detonation NDs with positive ζ-potential strongly associate with multiple FGF ligands present at sub-nanomolar concentrations and effectively neutralize the effects of FGF signalling in cells without interfering with other growth factor systems and serum proteins unrelated to FGFs. We identified an evolutionarily conserved FGF recognition motif, ∼17 amino acids long, that contributes to the selectivity of the ND-FGF interaction. In addition, we inserted this motif into a de novo constructed chimeric protein, which significantly improved its interaction with NDs. We demonstrated that the interaction of NDs, as purely inorganic nanoparticles, with proteins can mitigate pathological FGF signalling and promote the restoration of cartilage growth in a mouse limb explant model. Based on our observations, we foresee that NDs may potentially be applied as nanotherapeutics to neutralize disease-related activities of FGFs in vivo.

• Klíčová slova
• Cell signalling, FGF, Fibroblast growth factor, Nanodiamonds, Nanotherapeutics,
• MeSH
• aminokyselinové motivy MeSH
• buněčné linie MeSH
• chrupavka fyziologie   MeSH
• embryo savčí MeSH
• fibroblastové růstové faktory metabolismus   MeSH
• lidé MeSH
• ligandy MeSH
• myši MeSH
• nanodiamanty chemie   MeSH
• proliferace buněk MeSH
• receptory fibroblastových růstových faktorů metabolismus   MeSH
• signální transdukce MeSH
• techniky tkáňových kultur MeSH
• tibie fyziologie   MeSH
• vazba proteinů MeSH
• viabilita buněk MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fibroblastové růstové faktory MeSH
• ligandy MeSH
• nanodiamanty MeSH
• receptory fibroblastových růstových faktorů MeSH

Cellular function is modulated by the electric membrane potential controlling intracellular physiology and signal propagation from a motor neuron to a muscle fiber resulting in muscle contraction. Unlike electric fields, magnetic fields are not attenuated by biological materials and penetrate deep into the tissue. We used complex spatiotemporal magnetic fields (17-70 mT) to control intracellular signaling in skeletal muscle cells. By changing different parameters of the alternating magnetic field (amplitude, inversion time, rotation frequency), we induced transient depolarization of cellular membranes leading to i) Na+ influx through voltage-gated sodium channels (VGSC), ii) cytosolic calcium increase, and iii) VGSC- and ryanodine receptor-dependent increase of actin polymerization. The ion fluxes occurred only, when the field was applied and returned to baseline after the field was turned off. The 30-s-activation-cycle could be repeated without any loss of signal intensity. By contrast, static magnetic fields of the same strength exhibited no effect on myotube Ca2+ levels. Mathematical modeling suggested a role for the alternating magnetic field-induced eddy current, which mediates a local change in the membrane potential triggering the activation of VGSC. These findings might pave the way for the use of complex magnetic fields to improve function of skeletal muscles in myopathies.

• Klíčová slova
• Alternating magnetic field, Cytosolic calcium, Eddy current, Modeling, Skeletal muscle, Voltage-gated sodium channels,
• MeSH
• aktiny metabolismus   MeSH
• biologické modely MeSH
• buněčná membrána fyziologie   MeSH
• buněčné linie MeSH
• gating iontového kanálu MeSH
• kosterní svalová vlákna metabolismus   MeSH
• magnetické pole MeSH
• membránové potenciály MeSH
• myoblasty cytologie   MeSH
• myši MeSH
• polymerizace MeSH
• sodíkové kanálky řízené napětím fyziologie   MeSH
• vápník metabolismus   MeSH
• vápníková signalizace MeSH
• viabilita buněk MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• aktiny MeSH
• sodíkové kanálky řízené napětím MeSH
• vápník MeSH

The exceptionally high cellular uptake of gold nanorods (GNRs) bearing cationic surfactants makes them a promising tool for biomedical applications. Given the known specific toxic and stress effects of some preparations of cationic nanoparticles, the purpose of this study was to evaluate, in an in vitro and in vivo in mouse, the potential harmful effects of GNRs coated with (16-mercaptohexadecyl)trimethylammonium bromide (MTABGNRs). Interestingly, even after cellular accumulation of high amounts of MTABGNRs sufficient for induction of photothermal effect, no genotoxicity (even after longer-term accumulation), induction of autophagy, destabilization of lysosomes (dominant organelles of their cellular destination), alterations of actin cytoskeleton, or in cell migration could be detected in vitro. In vivo, after intravenous administration, the majority of GNRs accumulated in mouse spleen followed by lungs and liver. Microscopic examination of the blood and spleen showed that GNRs interacted with white blood cells (mononuclear and polymorphonuclear leukocytes) and thrombocytes, and were delivered to the spleen red pulp mainly as GNR-thrombocyte complexes. Importantly, no acute toxic effects of MTABGNRs administered as 10 or 50 μg of gold per mice, as well as no pathological changes after their high accumulation in the spleen were observed, indicating good tolerance of MTABGNRs by living systems.

• Klíčová slova
• Autophagy, Genotoxicity, Lysosomal stress, Plasmonic photothermal effect, Spleen, Thrombocytes,
• MeSH
• autofagie účinky léků   MeSH
• kvartérní amoniové sloučeniny metabolismus   MeSH
• lidé MeSH
• lyzozomy účinky léků   metabolismus   MeSH
• mezenchymální kmenové buňky cytologie   účinky léků   MeSH
• mikrofilamenta účinky léků   metabolismus   MeSH
• mutageny toxicita   MeSH
• myši inbrední C57BL MeSH
• nádorové buněčné linie MeSH
• nanotrubičky chemie   toxicita   ultrastruktura   MeSH
• podocyty účinky léků   metabolismus   MeSH
• pohyb buněk účinky léků   MeSH
• poškození DNA MeSH
• slezina účinky léků   patologie   MeSH
• sulfhydrylové sloučeniny metabolismus   MeSH
• tkáňová distribuce MeSH
• trombocyty účinky léků   patologie   ultrastruktura   MeSH
• zlato metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• (16-mercaptohexadecyl)trimethylammonium bromide MeSH Prohlížeč
• kvartérní amoniové sloučeniny MeSH
• mutageny MeSH
• sulfhydrylové sloučeniny MeSH
• zlato MeSH

We designed and synthesized a new delivery system for the anticancer drug doxorubicin based on a biocompatible hydrophilic poly(2-ethyl-2-oxazoline) (PEtOx) carrier with linear architecture and narrow molar mass distribution. The drug is connected to the polymer backbone via an acid-sensitive hydrazone linker, which allows its triggered release in the tumor. The in vitro studies demonstrate successful cellular uptake of conjugates followed by release of the cytostatic cargo. In vivo experiments in EL4 lymphoma bearing mice revealed prolonged blood circulation, increased tumor accumulation and enhanced antitumor efficacy of the PEtOx conjugate having higher molecular weight (40 kDa) compared to the lower molecular weight (20 kDa) polymer. Finally, the in vitro and in vivo anti-cancer properties of the prepared PEtOx conjugates were critically compared with those of the analogous system based on the well-established PHPMA carrier. Despite the relatively slower intracellular uptake of PEtOx conjugates, resulting also in their lower cytotoxicity, there are no substantial differences in in vivo biodistribution and anti-cancer efficacy of both classes of polymer-Dox conjugates. Considering the synthetic advantages of poly(2-alkyl-2-oxazoline)s, the presented study demonstrates their potential as a versatile alternative to well-known PEO- or PHPMA-based materials for construction of drug delivery systems.

• Klíčová slova
• Doxorubicin, Drug delivery, Hydrazone bond, Nanomedicine, Poly(2-oxazoline),
• MeSH
• akrylamidy chemie   MeSH
• doxorubicin chemie   terapeutické užití   MeSH
• HeLa buňky MeSH
• konfokální mikroskopie MeSH
• lidé MeSH
• MFC-7 buňky MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nanomedicína metody   MeSH
• nosiče léků chemie   MeSH
• polyaminy chemie   MeSH
• polymery chemie   MeSH
• průtoková cytometrie MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• akrylamidy MeSH
• doxorubicin MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• nosiče léků MeSH
• poly(2-ethyl-2-oxazoline) MeSH Prohlížeč
• polyaminy MeSH
• polymery MeSH