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1.
Front Immunol ; 12: 682094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335583

RESUMO

Peripheral neutrophils in HIV-infected individuals are characterized by impairment of chemotaxis, phagocytosis, bactericidal activity, and oxidative burst ability regardless of whether patients are receiving antiretroviral therapy or not. Neutrophil dysfunction leads not only to increased susceptibility to opportunistic infections but also to tissue damage through the release of reactive oxygen species (ROS), proteases, and other potentially harmful effector molecules contributing to AIDS progression. In this study, we demonstrated high levels of histone H3 lysine K4 trimethylated (H3K4me3) and dysregulation of DNA transcription in circulating neutrophils of HIV-infected subjects. This dysregulation was accompanied by a deficient response of neutrophils to LPS, impaired cytokine/chemokine/growth factor synthesis, and increased apoptosis. Chromatin immunoprecipitation sequencing (ChIPseq) H3K4me3 histone analysis revealed that the most spectacular abnormalities were observed in the exons, introns, and promoter-TSS regions. Bioinformatic analysis of Gene Ontology, including biological processes, molecular function, and cellular components, demonstrated that the main changes were related to the genes responsible for cell activation, cytokine production, adhesive molecule expression, histone remodeling via upregulation of methyltransferase process, and downregulation of NF-κB transcription factor in canonical pathways. Abnormalities within H3K4me3 implicated LPS-mediated NF-κB canonical activation pathway that was a result of low amounts of κB DNA sites within histone H3K4me3, low NF-κB (p65 RelA) and TLR4 mRNA expression, and reduced free NF-κB (p65 RelA) accumulation in the nucleus. Genome-wide survey of H3K4me3 provided evidence that chromatin modifications lead to an impairment within the canonical NF-κB cell activation pathway causing the neutrophil dysfunction observed in HIV-infected individuals.

2.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445145

RESUMO

The main goal of growing plants under various photoperiods is to optimize photosynthesis for using the effect of day length that often acts on plants in combination with biotic and/or abiotic stresses. In this study, Brassica juncea plants were grown under four different day-length regimes, namely., 8 h day/16 h night, 12 h day/12 h night, 16 h day/8 h night, and continuous light, and were infected with a necrotrophic fungus Alternaria brassicicola. The development of necroses on B. juncea leaves was strongly influenced by leaf position and day length. The largest necroses were formed on plants grown under a 16 h day/8 h night photoperiod at 72 h post-inoculation (hpi). The implemented day-length regimes had a great impact on leaf morphology in response to A. brassicicola infection. They also influenced the chlorophyll and carotenoid contents and photosynthesis efficiency. Both the 1st (the oldest) and 3rd infected leaves showed significantly higher minimal fluorescence (F0) compared to the control leaves. Significantly lower values of other investigated chlorophyll a fluorescence parameters, e.g., maximum quantum yield of photosystem II (Fv/Fm) and non-photochemical quenching (NPQ), were observed in both infected leaves compared to the control, especially at 72 hpi. The oldest infected leaf, of approximately 30% of the B. juncea plants, grown under long-day and continuous light conditions showed a 'green island' phenotype in the form of a green ring surrounding an area of necrosis at 48 hpi. This phenomenon was also reflected in changes in the chloroplast's ultrastructure and accelerated senescence (yellowing) in the form of expanding chlorosis. Further research should investigate the mechanism and physiological aspects of 'green islands' formation in this pathosystem.


Assuntos
Alternaria/patogenicidade , Mostardeira/microbiologia , Mostardeira/fisiologia , Necrose/microbiologia , Necrose/patologia , Fotossíntese/fisiologia , Doenças das Plantas/microbiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Fluorescência , Mostardeira/metabolismo , Necrose/metabolismo , Fotoperíodo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
3.
Dalton Trans ; 50(27): 9500-9511, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34254615

RESUMO

Carbosilane ruthenium(ii) dendrimers have been complexed with conventional anti-cancer drugs. Due to its features, the presence of ruthenium within a dendrimer structure improves the anti-cancer properties of nanocomplexes containing 5-flurouracyl, methotrexate and doxorubicin. These dendrimers could be promising carriers of anti-cancer medicines. Ruthenium dendrimers that are positively charged can also enhance the cytotoxicity to cancer cells; moreover, they can form stable complexes with drugs. Results indicate that ruthenium dendrimers combined with doxorubicin and methotrexate significantly reduced the viability of leukaemia 1301 and HL-60 cancer cells.

4.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281151

RESUMO

The application of siRNA in gene therapy is mainly limited because of the problems with its transport into cells. Utilization of cationic dendrimers as siRNA carriers seems to be a promising solution in overcoming these issues, due to their positive charge and ability to penetrate cell membranes. The following two types of carbosilane dendrimers were examined: CBD-1 and CBD-2. Dendrimers were complexed with pro-apoptotic siRNA (Mcl-1 and Bcl-2) and the complexes were characterized by measuring their zeta potential, circular dichroism and fluorescence of ethidium bromide associated with dendrimers. CBD-2/siRNA complexes were also examined by agarose gel electrophoresis. Both dendrimers form complexes with siRNA. Moreover, the cellular uptake and influence on the cell viability of the dendrimers and dendriplexes were evaluated using microscopic methods and XTT assay on MCF-7 cells. Microscopy showed that both dendrimers can transport siRNA into cells; however, a cytotoxicity assay showed differences in the toxicity of these dendrimers.


Assuntos
RNA Interferente Pequeno/uso terapêutico , Silanos/farmacologia , Cátions , Sobrevivência Celular , Dicroísmo Circular , Dendrímeros/química , Dendrímeros/farmacologia , Terapia Genética/métodos , Humanos , Células MCF-7 , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Tamanho da Partícula , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA de Cadeia Dupla/genética , RNA Interferente Pequeno/genética , Silanos/química , Silanos/metabolismo
5.
J Inorg Biochem ; 223: 111540, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273717

RESUMO

With the purpose of obtaining a new dendritic system against cancer, this paper is focused on the synthesis of spherical carbosilane metallodendrimers of different generations holding Ru(II) N-heterocyclic carbene (NHC) on the periphery from the imidazolium precursors. Both imidazolium salt dendrimers and their metallodendrimers counterparts showed promising anticancer activity, similar to cisplatin, mainly at high generations. In addition, both families of second and third generations were able to form dendriplexes with anticancer small interfering RNA (siRNA), protecting the cargo against RNAse and being able to internalize it in HEPG2 (human liver cancer) tumour cells. The characterization and effectiveness of the dendriplexes were evaluated by various analytical techniques such as zeta potential, electrophoresis and circular dichroism, the stability of the system and the protective nature of the dendrimer estimated using RNAse and the internalization of dendriplexes by confocal microscopy. The major advantage observed with the ruthenium metallodendrimers with respect to the imidazolium salts precursors was in cellular uptake, where the internalization of Mcl-1-FITC siRNA (myeloid cell leukaemia-1 fluorescein labelled siRNA) proceeded more efficiently. Therefore, we propose here that both imidazolium and Ru metallodendrimers are interesting candidates in cancer due to their double action, as anticancer per se and as carrier for anticancer siRNA, providing in this way a combined action.

6.
Int J Mol Sci ; 22(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808501

RESUMO

In this research, we prepared foam scaffolds based on poly(l-lactide) (PLLA) and apatite whiskers (HAP) using thermally induced phase separation technique supported by the salt leaching process (TIPS-SL). Using sodium chloride having a size of (a) 150-315 µm, (b) 315-400 µm, and (c) 500-600 µm, three types of foams with different pore sizes have been obtained. Internal structure of the obtained materials has been investigated using SEM as well as µCT. The materials have been studied by means of porosity, density, and compression tests. As the most promising, the composite prepared with salt size of 500-600 µm was prepared also with the l-lysine modified apatite. The osteoblast hFOB 1.19 cell response for the scaffolds was also investigated by means of cell viability, proliferation, adhesion/penetration, and biomineralization. Direct contact cytotoxicity assay showed the cytocompatibility of the scaffolds. All types of foam scaffolds containing HAP whiskers, regardless the pore size or l-lysine modification induced significant stimulatory effect on the cal-cium deposits formation in osteoblasts. The PLLA/HAP scaffolds modified with l-lysine stimulated hFOB 1.19 osteoblasts proliferation. Compared to the scaffolds with smaller pores (150-315 µm and 315-400 µm), the PLLA/HAP foams with large pores (500-600 µm) promoted more effective ad-hesion of osteoblasts to the surface of the biomaterial.


Assuntos
Durapatita/química , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Apatitas/química , Apatitas/metabolismo , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Humanos , Ácido Láctico/metabolismo , Lisina/química , Lisina/metabolismo , Osteoblastos/metabolismo , Poliésteres/metabolismo , Polímeros/química , Porosidade
7.
J Tissue Eng Regen Med ; 15(5): 463-474, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33735542

RESUMO

Epigenetic processes, such as DNA methylation and other chromatin modifications, are believed to be largely responsible for establishing a reduced capacity for growth in the mature nervous system. Ten-eleven translocation methylcytosine dioxygenase 3 (Tet3)-, a member of the Tet gene family, plays a crucial role in promoting injury-induced DNA demethylation and expression of regeneration-associated genes in the peripheral nervous system. Here, we encapsulate Tet3 protein within a clinically tolerated poly(lactide-co-glycolide) microsphere system. Next, we show that Tet3-loaded microspheres are internalized into mHippoE-18 embryonic hippocampal cells. We compare the outgrowth potential of Tet3 microspheres with that of commonly used nerve growth factor (NGF)-loaded microspheres in an in vitro injury model. Tet3-containing microspheres increased levels of nuclear 5-hydroxymethylcytosine indicating active demethylation and outperformed NGF-containing microspheres in measures of neurite outgrowth. Our results suggest that encapsulated demethylases may represent a novel avenue to treat nerve injuries.

9.
Sci Rep ; 11(1): 3849, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589697

RESUMO

Even though application of nanoparticles in medicine seems to provide unique solutions for drug delivery and diagnosis diseases, understanding interactions between nanoscale materials and biological systems is imperative. Therefore, this study determined the effect of different types of nanoparticles (NPs) on human endothelial cells and examined the types of toxicity responses they can induce. Four different types of NPs were tested (PLA/MMT/TRASTUZUMAB, PLA/EDTMP, PLGA/MDP, and Pluronic F127 MICELLES), representing three putative areas of application: anticancer therapy, scintigraphy, and cosmetology. The experiments were performed on immortalized human umbilical vein endothelial cells (HUVEC-STs). Light contrast phase microscopy as well as cell viability assays showed that only Pluronic F127 MICELLES decreased the number of HUVEC-STs in contrast to PLA/MMT/TRASTUZUMAB, PLA/EDTMP, and PLGA/MDP NPs, which altered cell morphology, but not their confluency. The tested NPs induced not only DNA strand-breaks and alkali-labile sites, but also internucleosomal DNA fragmentation, visualized as a DNA ladder pattern typical of apoptosis. Moreover, generation of free radicals and subsequent mitochondrial membrane potential collapse showed the significance of free radical production during interactions between NPs and endothelial cells. High concentrations of NPs had different degrees of toxicity in human endothelial cells and affected cell proliferation, redox homeostasis, and triggered mitochondrial dysfunction.

10.
Langmuir ; 37(4): 1542-1550, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33475368

RESUMO

The unavailability of effective and safe human immunodeficiency virus (HIV) vaccines incites several approaches for development of the efficient antigen/adjuvant vaccination composite. In this study, three different dendronized gold nanoparticles (AuNPs 13-15) were investigated for a complexation ability with gp160 synthetic peptides derived from an HIV envelope. It has been shown that HIV peptides interacted with nanoparticles as evident from the changes in their secondary structures, restricted the mobility of the attached fluorescence dye, and enhanced peptide helicity confirmed by the fluorescence polarization and circular dichroism results. Transmission electron microscopy visualized complexes as cloud-like structures with attached nanoparticles. AuNP 13-15 nanoparticles bind negatively charged peptides depending on the number of functional groups; the fastest saturation and peptide retardation were observed for the most dendronized nanoparticle as indicated from dynamic light scattering, laser Doppler velocimetry, and agarose gel electrophoresis experiments. Dendronized gold nanoparticles can be considered one of the potential HIV peptide-based vaccination platforms.


Assuntos
HIV-1 , Nanopartículas Metálicas , Ouro , Proteína gp160 do Envelope de HIV , Humanos , Microscopia Eletrônica de Transmissão , Peptídeos
12.
Sci Rep ; 10(1): 13574, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782343

RESUMO

Widespread occurrence of ZnO nanoparticles in environment follows the growing number of applications either in technology or agriculture. The impact of five forms of nanoparticulate ZnO on copper, manganese and iron uptake by Pisum sativum L. cultivated in Hoagland solutions was investigated. Plants were collected after twelve days of zinc administration. Effect of bulk ZnO has also been studied. Initial zinc concentration was 100 mg L-1. Nanoparticles were characterized by the Transmission Electron Microscopy, Dynamic Light Scattering and Zeta potential measurements. Metal contents were analyzed using the Atomic Absorption Spectrometry with flame atomization for samples digested in a microwave closed system. Analysis of variance indicated that zinc species at either molecular or nanoscale levels altered Cu, Mn and Fe uptake and their further transport in pea plants. In particular, significant reduction of Mn and Fe combined with the Cu increase was observed. Additive interactions originated by nanoparticles affect the heavy metals uptake and indicate pollutants migration pathways in plants. Unfortunately, regulations for the plant cultivation were formulated when anthropogenic nanoparticles were not in common use. They underestimate complexity of metals interactions in either plant or habitat. Our results indicate that these additive interactions cannot be neglected and deserve further investigations.

13.
Pharmaceutics ; 12(8)2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748821

RESUMO

Cancer treatment with small interfering RNA (siRNA) is one of the most promising new strategies; however, transfection systems that increase its bioavailability and ensure its delivery to the target cell are necessary. Transfection systems may be just vehicular or could contain fragments with anticancer activity that achieves a synergistic effect with siRNA. Cationic carbosilane dendrimers have proved to be powerful tools as non-viral vectors for siRNA in cancer treatment, and their activity might be potentiated by the inclusion of metallic complexes in its dendritic structure. We have herein explored the interaction between Schiff-base carbosilane copper (II) metallodendrimers, and pro-apoptotic siRNAs. The nanocomplexes formed by metallodendrimers and different siRNA have been examined for their zeta potential and size, and by transmission electron microscopy, fluorescence polarisation, circular dichroism, and electrophoresis. The internalisation of dendriplexes has been estimated by flow cytometry and confocal microscopy in a human breast cancer cell line (MCF-7), following the ability of these metallodendrimers to deliver the siRNA into the cell. Finally, in vitro cell viability experiments have indicated effective interactions between Cu (II) dendrimers and pro-apoptotic siRNAs: Mcl-1 and Bcl-2 in breast cancer cells. Combination of the first-generation derivatives with chloride counterions and with siRNA increases the anticancer activity of the dendriplex constructs and makes them a promising non-viral vector.

14.
Cells ; 9(7)2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32629890

RESUMO

The transcription factor Snail triggers epithelial-to-mesenchymal transition (EMT), endowing cancer cells with invasive properties during tumor progression. Extracellular vesicles (EVs) released from cancer cells at various stages of cancer progression are known to influence the tumor pre-metastatic niche and metastatic potential. The aim of this study was to analyze the effect of Snail on murine colon adenocarcinoma cells (MC38 line) and on the characteristics of their EVs. Stable clones of Snail-overexpressing MC38 cells were investigated in vitro versus Mock cells. Increased expression of matrix metalloproteinase MMP-14 and augmented activity of MMP-9 and -14 were observed in Snail-MC38 cells. There was no change in the transcriptomic profile of proteoglycans in Snail-MC38 cells; however, the protein level of Glypican-1 (GPC1) was enhanced in EVs released from those cells. Our finding that GPC1 protein level was enhanced in EVs released from MC38 cells that overexpressed Snail and were in an early EMT stage might explain the specificity of the GPC1 biomarker in colon cancer diagnosis. Further, our data suggest that Snail, by changing the level of GPC1 on EVs released by colon cancer cells, may affect the generation of a distant premetastatic niche and metastatic organotropism in colon adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias do Colo/metabolismo , Adenocarcinoma/genética , Animais , Neoplasias do Colo/genética , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Vesículas Extracelulares/metabolismo , Glipicanas/metabolismo , Células HT29 , Humanos , Metaloproteinase 14 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Fatores de Transcrição da Família Snail/metabolismo
15.
Int J Mol Sci ; 21(11)2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526993

RESUMO

Ruthenium atoms located in the surfaces of carbosilane dendrimers markedly increase their anti-tumor properties. Carbosilane dendrimers have been widely studied as carriers of drugs and genes owing to such characteristic features as monodispersity, stability, and multivalence. The presence of ruthenium in the dendrimer structure enhances their successful use in anti-cancer therapy. In this paper, the activity of dendrimers of generation 1 and 2 against 1301 cells was evaluated using Transmission Electron Microscopy, comet assay and Real Time PCR techniques. Additionally, the level of reactive oxygen species (ROS) and changes of mitochondrial potential values were assessed. The results of the present study show that ruthenium dendrimers significantly decrease the viability of leukemia cells (1301) but show low toxicity to non-cancer cells (peripheral blood mononuclear cells-PBMCs). The in vitro test results indicate that the dendrimers injure the 1301 leukemia cells via the apoptosis pathway.


Assuntos
Antineoplásicos/farmacologia , Dendrímeros/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Rutênio/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dendrímeros/química , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Espécies Reativas de Oxigênio/metabolismo , Rutênio/química
16.
Int J Mol Sci ; 21(7)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32224851

RESUMO

The aim of this study was to investigate the uptake and accumulation of fullerenol C60(OH)36 into peripheral blood mononuclear cells (PBMCs). Some additional studies were also performed: measurement of fullerenol nanoparticle size, zeta potential, and the influence of fullerenol on the ionizing radiation-induced damage to PMBCs. Fullerenol C60(OH)36 demonstrated an ability to accumulate in PBMCs. The accumulation of fullerenol in those cells did not have a significant effect on cell survival, nor on the distribution of phosphatidylserine in the plasma membrane. However, fullerenol-induced depolarization of the mitochondrial membrane proportional to the compound level in the medium was observed. Results also indicated that increased fullerenol level in the medium was associated with its enhanced transport into cells, corresponding to its influence on the mitochondrial membrane. The obtained results clearly showed the ability of C60(OH)36 to enter cells and its effect on PBMC mitochondrial membrane potential. However, we did not observe radioprotective properties of fullerenol under the conditions used in our study.


Assuntos
Fulerenos/farmacologia , Monócitos/metabolismo , Nanopartículas/metabolismo , Transporte Biológico , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Fulerenos/química , Humanos , Potencial da Membrana Mitocondrial , Monócitos/efeitos dos fármacos , Monócitos/efeitos da radiação , Nanopartículas/química , Radiação Ionizante
17.
J Vis Exp ; (157)2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-32225161

RESUMO

Crohn's disease is the most diagnosed type of inflammatory bowel disease. Chronic inflammation developing in the intestine leads to peristalsis disorder and damage of intestinal mucosa and seems to be associated with an increased risk of colon neoplastic transformation. Accumulating evidence indicates that estrogens and estrogen receptors affect not only hormone-sensitive tissues, but also other tissues not directly related to estrogens, such as the lungs or colon. Here, we describe the protocol for the successful immunofluorescence staining of estrogen receptors in colon obtained from a murine model of TNBS-induced Crohn's disease. A detailed protocol for the induction of Crohn's disease in mice and intestine preparation is provided as well as a step-by-step immunohistochemical procedure using formalin-fixed paraffin-embedded intestine sections. The described methods are not only useful for estrogen receptor detection and estrogen signaling investigation in vivo but can also be applied to for other proteins which may be involved in the development of colitis.


Assuntos
Colo/metabolismo , Doença de Crohn/fisiopatologia , Imunofluorescência/métodos , Receptores de Estrogênio/metabolismo , Animais , Colo/citologia , Humanos , Camundongos
18.
Biomolecules ; 10(3)2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182909

RESUMO

Dendrimers as drug carriers can be utilized for drugs and siRNA delivery in central nervous system (CNS) disorders, including various types of cancers, such as neuroblastomas and gliomas. They have also been considered as drugs per se, for example as anti-Alzheimer's disease (AD), anti-cancer, anti-prion or anti-inflammatory agents. Since the influence of carbosilane-viologen-phosphorus dendrimers (SMT1 and SMT2) on the basic cellular processes of nerve cells had not been investigated, we examined the impact of two generations of these hybrid macromolecules on two murine cell lines-cancer cell line N2a (mouse neuroblastoma) and normal immortalized cell line mHippoE-18 (embryonic mouse hippocampal cell line). We examined alterations in cellular responses including the activity of mitochondrial dehydrogenases, the generation of reactive oxygen species (ROS), changes in mitochondrial membrane potential, and morphological modifications and fractions of apoptotic and dead cells. Our results show that both dendrimers at low concentrations affected the cancer cell line more than the normal one. Also, generation-dependent effects were found: the highest generation induced greater cytotoxic effects and morphological modifications. The most promising is that the changes in mitochondrial membrane potential and transmission electron microscopy (TEM) images indicate that dendrimer SMT1 can reach mitochondria. Thus, SMT1 and SMT2 seem to have potential as nanocarriers to mitochondria or anti-cancer drugs per se in CNS disorders.


Assuntos
Dendrímeros/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias , Neuroblastoma , Neurônios , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular Tumoral , Dendrímeros/química , Camundongos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Neuroblastoma/ultraestrutura , Neurônios/metabolismo , Neurônios/ultraestrutura
19.
Cells ; 9(1)2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861635

RESUMO

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system (CNS) mediated by autoreactive lymphocytes. The role of autoreactive lymphocytes in the CNS demyelination is well described, whereas very little is known about their role in remyelination during MS remission. In this study, we identified a new subpopulation of myelin-specific CD49d+CD154+ lymphocytes presented in the peripheral blood of MS patients during remission, that proliferated in vitro in response to myelin peptides. These lymphocytes possessed the unique ability to migrate towards maturing oligodendrocyte precursor cells (OPCs) and synthetize proinflammatory chemokines/cytokines. The co-culture of maturing OPCs with myelin-specific CD49d+CD154+ lymphocytes was characterized by the increase in proinflammatory chemokine/cytokine secretion that was not only a result of their cumulative effect of what OPCs and CD49d+CD154+ lymphocytes produced alone. Moreover, maturing OPCs exposed to exogenous myelin peptides managed to induce CD40-CD154-dependent CD49d+CD154+ lymphocyte proliferation. We confirmed, in vivo, the presence of CD49d+CD154+ cells close to maturating OPCs and remyelinating plaque during disease remission in the MS mouse model (C57Bl/6 mice immunized with MOG35-55) by immunohistochemistry. Three weeks after an acute phase of experimental autoimmune encephalomyelitis, CD49d+/CD154+ cells were found to be co-localized with O4+ cells (oligodendrocyte progenitors) in the areas of remyelination identified by myelin basic protein (MBP) labelling. These data suggested that myelin-specific CD49d+CD154+ lymphocytes present in the brain can interfere with remyelination mediated by oligodendrocytes probably as a result of establishing proinflammatory environment.


Assuntos
Ligante de CD40/metabolismo , Encefalomielite Autoimune Experimental/imunologia , Integrina alfa4/metabolismo , Esclerose Múltipla/imunologia , Bainha de Mielina/metabolismo , Adulto , Animais , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Linfócitos/citologia , Linfócitos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito/efeitos adversos , Células Precursoras de Oligodendrócitos/citologia , Células Precursoras de Oligodendrócitos/imunologia , Fragmentos de Peptídeos/efeitos adversos , Remielinização
20.
Cells ; 8(12)2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775315

RESUMO

The critical aspect in multiple sclerosis (MS) progression involves insufficient regeneration of CNS resulting from deficient myelin synthesis by newly generated oligodendrocytes (OLs). Although many studies have focused on the role of autoreactive lymphocytes in the inflammatory-induced axonal loss, the problem of insufficient remyelination and disease progression is still unsolved. To determine the effect of myelin-specific lymphocytes on OL function in MS patients and in a mouse model of MS, we cultured myelin induced MS CD49d+CD154+ circulating lymphocytes as well as Experimental Autoimmune Encephalomyelitis (EAE) mouse brain-derived T and memory B cells with maturing oligodendrocyte precursor cells (OPCs). We found that myelin-specific CD49d+CD154+ lymphocytes affected OPC maturation toward formation of immune reactive OLs. Newly generated OLs were characterized by imbalanced myelin basic protein (MBP) and proteolipid protein (PLP) production as well as proinflammatory chemokine/cytokine synthesis. The analysis of cellular pathways responsible for OL reprogramming revealed that CD49d+CD154+ lymphocytes affected miRNA synthesis by dysregulation of polymerase II activity. miR-665 and ELL3 turned out to be the main targets of MS myelin-specific lymphocytes. Neutralization of high intracellular miR-665 concentration restored miRNA and MBP/PLP synthesis. Together, these data point to new targets for therapeutic intervention promoting CNS remyelination.


Assuntos
Linfócitos , Esclerose Múltipla , Oligodendroglia , Remielinização , Adulto , Animais , Linhagem Celular , Feminino , Humanos , Linfócitos/imunologia , Linfócitos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Proteína Básica da Mielina/imunologia , Proteína Proteolipídica de Mielina/imunologia , Oligodendroglia/imunologia , Oligodendroglia/patologia , Fatores de Elongação da Transcrição/imunologia
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