[This corrects the article DOI: 10.3389/fcell.2021.695900.].

• Klíčová slova
• amyotrophic lateral sclerosis, biomaterials, cell therapy, conditioned medium, exosomes, mesenchymal stem cells, neurodegenerative diseases, spinal cord injury,
• Publikační typ
• tisková chyba MeSH

Preclinical and clinical studies with various stem cells, their secretomes, and extracellular vesicles (EVs) indicate their use as a promising strategy for the treatment of various diseases and tissue defects, including neurodegenerative diseases such as spinal cord injury (SCI) and amyotrophic lateral sclerosis (ALS). Autologous and allogenic mesenchymal stem cells (MSCs) are so far the best candidates for use in regenerative medicine. Here we review the effects of the implantation of MSCs (progenitors of mesodermal origin) in animal models of SCI and ALS and in clinical studies. MSCs possess multilineage differentiation potential and are easily expandable in vitro. These cells, obtained from bone marrow (BM), adipose tissue, Wharton jelly, or even other tissues, have immunomodulatory and paracrine potential, releasing a number of cytokines and factors which inhibit the proliferation of T cells, B cells, and natural killer cells and modify dendritic cell activity. They are hypoimmunogenic, migrate toward lesion sites, induce better regeneration, preserve perineuronal nets, and stimulate neural plasticity. There is a wide use of MSC systemic application or MSCs seeded on scaffolds and tissue bridges made from various synthetic and natural biomaterials, including human decellularized extracellular matrix (ECM) or nanofibers. The positive effects of MSC implantation have been recorded in animals with SCI lesions and ALS. Moreover, promising effects of autologous as well as allogenic MSCs for the treatment of SCI and ALS were demonstrated in recent clinical studies.

• Klíčová slova
• amyotrophic lateral sclerosis, biomaterials, cell therapy, conditioned medium, exosomes, mesenchymal stem cells, neurodegenerative diseases, spinal cord injury,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Superparamagnetic iron oxide nanoparticles (SPIOn) are widely used as a contrast agent for cell labeling. Macrophages are the first line of defense of organisms in contact with nanoparticles after their administration. In this study we investigated the effect of silica-coated nanoparticles (γ-Fe2O3-SiO2) with or without modification by an ascorbic acid (γ-Fe2O3-SiO2-ASA), which is meant to act as an antioxidative agent on rat peritoneal macrophages. Both types of nanoparticles were phagocytosed by macrophages in large amounts as confirmed by transmission electron microscopy and Prusian blue staining, however they did not substantially affect the viability of exposed cells in monitored intervals. We further explored cytotoxic effects related to oxidative stress, which is frequently documented in cells exposed to nanoparticles. Our analysis of double strand breaks (DSBs) marker γH2AX showed an increased number of DSBs in cells treated with nanoparticles. Nanoparticle exposure further revealed only slight changes in the expression of genes involved in oxidative stress response. Lipid peroxidation, another marker of oxidative stress, was not significantly affirmed after nanoparticle exposure. Our data indicate that the effect of both types of nanoparticles on cell viability, or biomolecules such as DNA or lipids, was similar; however the presence of ascorbic acid, either bound to the nanoparticles or added to the cultivation medium, worsened the negative effect of nanoparticles in various tests performed. The attachment of ascorbic acid on the surface of nanoparticles did not have a protective effect against induced cytotoxicity, as expected.

• Klíčová slova
• Cytotoxicity, Macrophages, Nanoparticles, Oxidative stress,
• MeSH
• antioxidancia metabolismus   toxicita   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• kyselina askorbová metabolismus   toxicita   MeSH
• magnetické nanočástice toxicita   MeSH
• peritoneální makrofágy účinky léků   metabolismus   MeSH
• potkani Wistar MeSH
• synergismus léků MeSH
• viabilita buněk účinky léků   fyziologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antioxidancia MeSH
• kyselina askorbová MeSH
• magnetické nanočástice MeSH

INTRODUCTION: Rat mesenchymal stem cells (rMSCs) labeled with 1) poly-l-lysine-coated superparamagnetic iron oxide nanoparticles or 2) silica-coated cobalt-zinc-iron nanoparticles were implanted into the left brain hemisphere of rats, to assess their effects on the levels of oxidative damage to biological macromolecules in brain tissue. METHODS: Controls were implanted with unlabeled rMSCs. Animals were sacrificed 24 hours or 4 weeks after the treatment, and the implantation site along with the surrounding tissue was isolated from the brain. At the same intervals, parallel groups of animals were scanned in vivo by magnetic resonance imaging (MRI). The comet assay with enzymes of excision DNA repair (endonuclease III and formamidopyrimidine-DNA glycosylase) was used to analyze breaks and oxidative damage to DNA in the brain tissue. Oxidative damage to proteins and lipids was determined by measuring the levels of carbonyl groups and 15-F2t-isoprostane (enzyme-linked immunosorbent assay). MRI displayed implants of labeled cells as extensive hypointense areas in the brain tissue. In histological sections, the expression of glial fibrillary acidic protein and CD68 was analyzed to detect astrogliosis and inflammatory response. RESULTS: Both contrast labels caused a similar response in the T2-weighted magnetic resonance (MR) image and the signal was clearly visible within 4 weeks after implantation of rMSCs. No increase of oxidative damage to DNA, lipids, or proteins over the control values was detected in any sample of brain tissue from the treated animals. Also, immunohistochemistry did not indicate any serious tissue impairment around the graft. CONCLUSION: Both tested types of nanoparticles appear to be prospective and safe labels for tracking the transplanted cells by MR.

• Klíčová slova
• MRI, cell transplantation, comet assay, genotoxicity, lipid peroxidation, protein oxidative damage,
• MeSH
• dinoprost analogy a deriváty   MeSH
• ELISA MeSH
• isoprostany analýza   metabolismus   MeSH
• kobalt chemie   MeSH
• kovové nanočástice aplikace a dávkování   chemie   toxicita   MeSH
• magnetická rezonanční tomografie metody   MeSH
• mezenchymální kmenové buňky chemie   MeSH
• mozek diagnostické zobrazování   účinky léků   metabolismus   MeSH
• oxid křemičitý chemie   MeSH
• potkani inbrední LEW MeSH
• prospektivní studie MeSH
• tkáňové extrakty MeSH
• transplantace mezenchymálních kmenových buněk * MeSH
• železité sloučeniny chemie   MeSH
• železo chemie   MeSH
• zinek chemie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 8-epi-prostaglandin F2alpha MeSH Prohlížeč
• dinoprost MeSH
• ferric oxide MeSH Prohlížeč
• isoprostany MeSH
• kobalt MeSH
• oxid křemičitý MeSH
• tkáňové extrakty MeSH
• železité sloučeniny MeSH
• železo MeSH
• zinek MeSH

Spinal cord injury (SCI) results in neural loss and consequently motor and sensory impairment below the injury. There are currently no effective therapies for the treatment of traumatic SCI in humans. Various animal models have been developed to mimic human SCI. Widely used animal models of SCI are complete or partial transection or experimental contusion and compression, with both bearing controversy as to which one more appropriately reproduces the human SCI functional consequences. Here we present in details the widely used procedure of complete spinal cord transection as a faithful animal model to investigate neural and functional repair of the damaged tissue by exogenous human transplanted cells. This injury model offers the advantage of complete damage to a spinal cord at a defined place and time, is relatively simple to standardize and is highly reproducible.

• MeSH
• embryonální kmenové buňky MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• modely nemocí na zvířatech * MeSH
• poranění míchy patologie   patofyziologie   terapie   MeSH
• translační biomedicínský výzkum * MeSH
• transplantace buněk * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The manipulation of brain nerve terminals by an external magnetic field promises breakthroughs in nano-neurotechnology. D-Mannose-coated superparamagnetic nanoparticles were synthesized by coprecipitation of Fe(II) and Fe(III) salts followed by oxidation with sodium hypochlorite and addition of D-mannose. Effects of D-mannose-coated superparamagnetic maghemite (γ-Fe2O3) nanoparticles on key characteristics of the glutamatergic neurotransmission were analysed. Using radiolabeled L-[(14)C]glutamate, it was shown that D-mannose-coated γ-Fe2O3 nanoparticles did not affect high-affinity Na(+)-dependent uptake, tonic release and the extracellular level of L-[(14)C]glutamate in isolated rat brain nerve terminals (synaptosomes). Also, the membrane potential of synaptosomes and acidification of synaptic vesicles was not changed as a result of the application of D-mannose-coated γ-Fe2O3 nanoparticles. This was demonstrated with the potential-sensitive fluorescent dye rhodamine 6G and the pH-sensitive dye acridine orange. The study also focused on the analysis of the potential use of these nanoparticles for manipulation of nerve terminals by an external magnetic field. It was shown that more than 84.3 ± 5.0% of L-[(14)C]glutamate-loaded synaptosomes (1 mg of protein/mL) incubated for 5 min with D-mannose-coated γ-Fe2O3 nanoparticles (250 µg/mL) moved to an area, in which the magnet (250 mT, gradient 5.5 Т/m) was applied compared to 33.5 ± 3.0% of the control and 48.6 ± 3.0% of samples that were treated with uncoated nanoparticles. Therefore, isolated brain nerve terminals can be easily manipulated by an external magnetic field using D-mannose-coated γ-Fe2O3 nanoparticles, while the key characteristics of glutamatergic neurotransmission are not affected. In other words, functionally active synaptosomes labeled with D-mannose-coated γ-Fe2O3 nanoparticles were obtained.

• Klíčová slova
• D-mannose, extracellular level, glutamate uptake and release, manipulation by an external magnetic field, membrane potential, nanoparticles, rat brain nerve terminals, synaptic vesicle acidification, γ-Fe2O3,
• Publikační typ
• časopisecké články MeSH

The transplantation of mesenchymal stem cells (MSC) is currently under study as a therapeutic approach for spinal cord injury, and the number of transplanted cells that reach the lesioned tissue is one of the critical parameters. In this study, intrathecally transplanted cells labeled with superparamagnetic iron oxide nanoparticles were guided by a magnetic field and successfully targeted near the lesion site in the rat spinal cord. Magnetic resonance imaging and histological analysis revealed significant differences in cell numbers and cell distribution near the lesion site under the magnet in comparison to control groups. The cell distribution correlated well with the calculated distribution of magnetic forces exerted on the transplanted cells in the subarachnoid space and lesion site. The kinetics of the cells' accumulation near the lesion site is described within the framework of a mathematical model that reveals those parameters critical for cell targeting and suggests ways to enhance the efficiency of magnetic cell delivery. In particular, we show that the targeting efficiency can be increased by using magnets that produce spatially modulated stray fields. Such magnetic systems with tunable geometric parameters may provide the additional level of control needed to enhance the efficiency of stem cell delivery in spinal cord injury.

• Klíčová slova
• magnetism, mesenchymal stem cell, modeling, nanoparticle, spinal cord injury,
• MeSH
• histocytochemie MeSH
• krysa rodu Rattus MeSH
• magnetické nanočástice aplikace a dávkování   chemie   terapeutické užití   MeSH
• magnety * MeSH
• mezenchymální kmenové buňky chemie   cytologie   MeSH
• mícha chemie   cytologie   MeSH
• poranění míchy chirurgie   MeSH
• potkani Sprague-Dawley MeSH
• spinální injekce MeSH
• teoretické modely MeSH
• transplantace mezenchymálních kmenových buněk metody   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• magnetické nanočástice MeSH

OBJECT: Metabolite changes in an experimental lesion in the rat cortex and in the contralateral hemisphere after the intravenous administration of mesenchymal stem cells (MSCs) were assessed by proton MR spectroscopy to verify the impact of the cell treatment on the brain tissue. MATERIALS AND METHODS: Wistar rats with a photochemical cortical lesion and transplanted MSCs or sham transplanted rats were examined. Proton spectra were obtained from the lesion and from the contralateral cortex. RESULTS: Magnetic resonance spectroscopy revealed a gradual recovery of the damaged tissue; however, we found no significant differences in metabolite concentrations in the lesioned hemisphere between treated and untreated animals. Higher concentrations of glutamate and N-acetyl aspartate were found in the contralateral hemisphere in cell-treated animals compared to untreated ones. Lesioned animals showed neurogenesis in the contralateral hemisphere; the number of newly generated cells in stem cell-treated animals was 50% higher than those observed in untreated animals. CONCLUSION: No direct impact of cell transplantation was observed in the lesion. However, changes in the contralateral hemisphere suggest that the transplanted MSCs might stimulate repair processes and plasticity resulting in the generation of newborn cells, which might enable the faster adoption of the damaged tissue's function by healthy tissue.

• MeSH
• časové faktory MeSH
• femur patologie   MeSH
• ferrokyanidy farmakologie   MeSH
• krysa rodu Rattus MeSH
• kyselina asparagová analogy a deriváty   metabolismus   MeSH
• kyselina glutamová metabolismus   MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• mezenchymální kmenové buňky cytologie   MeSH
• mozek metabolismus   patologie   MeSH
• potkani Wistar MeSH
• transplantace mezenchymálních kmenových buněk metody   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ferric ferrocyanide MeSH Prohlížeč
• ferrokyanidy MeSH
• kyselina asparagová MeSH
• kyselina glutamová MeSH
• N-acetylaspartate MeSH Prohlížeč

1. Emerging clinical studies of treating brain and spinal cord injury (SCI) led us to examine the effect of autologous adult stem cell transplantation as well as the use of polymer scaffolds in spinal cord regeneration. We compared an intravenous injection of mesenchymal stem cells (MSCs) or the injection of a freshly prepared mononuclear fraction of bone marrow cells (BMCs) on the treatment of an acute or chronic balloon-induced spinal cord compression lesion in rats. Based on our experimental studies, autologous BMC implantation has been used in a Phase I/II clinical trial in patients (n=20) with a transversal spinal cord lesion. 2. MSCs were isolated from rat bone marrow by their adherence to plastic, labeled with iron-oxide nanoparticles and expanded in vitro. Macroporous hydrogels based on derivatives of 2-hydroxyethyl methacrylate (HEMA) or 2-hydroxypropyl methacrylamide (HPMA) were prepared, then modified by their copolymerization with a hydrolytically degradable crosslinker, N,O-dimethacryloylhydroxylamine, or by different surface electric charges. Hydrogels or hydrogels seeded with MSCs were implanted into rats with hemisected spinal cords. 3. Lesioned animals grafted with MSCs or BMCs had smaller lesions 35 days postgrafting and higher scores in BBB testing than did control animals and also showed a faster recovery of sensitivity in their hind limbs using the plantar test. The functional improvement was more pronounced in MSC-treated rats. In MR images, the lesion populated by grafted cells appeared as a dark hypointense area and was considerably smaller than in control animals. Morphometric measurements showed an increase in the volume of spared white matter in cell-treated animals. In the clinical trial, we compared intraarterial (via a. vertebralis, n=6) versus intravenous administration of BMCs (n=14) in a group of subacute (10-33 days post-SCI, n=8) and chronic patients (2-18 months, n=12). For patient follow-up we used MEP, SEP, MRI, and the ASIA score. Our clinical study revealed that the implantation of BMCs into patients is safe, as there were no complications following cell administration. Partial improvement in the ASIA score and partial recovery of MEP or SEP have been observed in all subacute patients who received cells via a. vertebralis (n=4) and in one out of four subacute patients who received cells intravenously. Improvement was also found in one chronic patient who received cells via a. vertebralis. A much larger population of patients is needed before any conclusions can be drawn. The implantation of hydrogels into hemisected rat spinal cords showed that cellular ingrowth was most pronounced in copolymers of HEMA with a positive surface electric charge. Although most of the cells had the morphological properties of connective tissue elements, we found NF-160-positive axons invading all the implanted hydrogels from both the proximal and distal stumps. The biodegradable hydrogels degraded from the border that was in direct contact with the spinal cord tissue. They were resorbed by macrophages and replaced by newly formed tissue containing connective tissue elements, blood vessels, GFAP-positive astrocytic processes, and NF-160-positive neurofilaments. Additionally, we implanted hydrogels seeded with nanoparticle-labeled MSCs into hemisected rat spinal cords. Hydrogels seeded with MSCs were visible on MR images as hypointense areas, and subsequent Prussian blue histological staining confirmed positively stained cells within the hydrogels. 4. We conclude that treatment with different bone marrow cell populations had a positive effect on behavioral outcome and histopathological assessment after SCI in rats; this positive effect was most pronounced following MSC treatment. Our clinical study suggests a possible positive effect in patients with SCI. Bridging the lesion cavity can be an approach for further improving regeneration. Our preclinical studies showed that macroporous polymer hydrogels based on derivatives of HEMA or HPMA are suitable materials for bridging cavities after SCI; their chemical and physical properties can be modified to a specific use, and 3D implants seeded with different cell types may facilitate the ingrowth of axons.

• MeSH
• autologní transplantace MeSH
• buňky kostní dřeně fyziologie   MeSH
• hydrogely terapeutické užití   MeSH
• komprese míchy terapie   MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• mezenchymální kmenové buňky fyziologie   MeSH
• monocyty transplantace   MeSH
• pohyb buněk MeSH
• polymery terapeutické užití   MeSH
• poranění míchy terapie   MeSH
• regenerace nervu MeSH
• transplantace kostní dřeně metody   MeSH
• transplantace mezenchymálních kmenových buněk metody   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• hydrogely MeSH
• polymery MeSH