RESUMO
OBJECTIVES: To assess and compare the cell viability and ion release profiles of two conventional glass ionomer cements (GICs), Fuji IX and Ketac Molar EasyMix, modified with TiO2 and Mg-doped-HAp nanoparticles (NPs). METHODS: TiO2 NPs, synthesized via a sol-gel method, and Mg-doped hydroxyapatite, synthesized via a hydrothermal process, were incorporated into GICs at a concentration of 5 wt.%. The biocompatibility of prepared materials was assessed by evaluating their effects on the viability of dental pulp stem cells (DPSCs), together with monitoring ion release profiles. Statistical analysis was performed using One-way analysis of variance, with significance level p < 0.05. RESULTS: The addition of NPs did not significantly affect the biocompatibility of GICs, as evidenced by comparable decreased levels in cell viability to their original formulations. Distinct variations in cell viability were observed among Fuji IX and Ketac Molar, including their respective modifications. FUJI IX and its modification with TiO2 exhibited moderate decrease in cell viability, while other groups exhibited severe negative effects. While slight differences in ion release profiles were observed among the groups, significant variations compared to original cements were not achieved. Fluoride release exhibited an initial "burst release" within the initial 24 h in all samples, stabilizing over subsequent days. CONCLUSIONS: The addition of NPs did not compromise biocompatibility, nor anticariogenic potential of tested GICs. However, observed differences among FUJI IX and Ketac Molar, including their respective modifications, as well as induced low viability of DPSC by all tested groups, suggest the need for careful consideration of cement composition in their biological assessments. CLINICAL SIGNIFICANCE: The findings contribute to understanding the complex interaction between NPs and GIC matrices. However, the results should be interpreted recognizing the inherent limitations associated with in vitro studies. Further research avenues could explore long-term effects, in vivo performance, and potential clinical applications.
Assuntos
Sobrevivência Celular , Polpa Dentária , Durapatita , Fluoretos , Cimentos de Ionômeros de Vidro , Magnésio , Teste de Materiais , Nanopartículas , Titânio , Titânio/química , Cimentos de Ionômeros de Vidro/química , Sobrevivência Celular/efeitos dos fármacos , Durapatita/química , Humanos , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Nanopartículas/química , Fluoretos/química , Magnésio/química , Células-Tronco/efeitos dos fármacos , Materiais Biocompatíveis/química , Íons , Células CultivadasRESUMO
INTRODUCTION: BioRoot Flow (BRF) is a novel premixed bioceramic sealer indicated for endodontic treatments, but the biological and immunomodulatory effects of this endodontic sealer on human periodontal ligament stem cells (hPDLSCs) have not been elucidated. METHODS: To ascertain the biological impact of BRF, TotalFill BC Sealer (TFbc), and AH Plus (AHP) on human Periodontal Ligament Stem Cells (hPDLSCs), assessments were conducted to evaluate the cytocompatibility, cellular proliferation, migratory capacity, osteo/cementogenic differentiation potential, the ability to form mineralized nodules, and the immunomodulatory characteristics of hPDLSCs following treatment with these endodontic sealers. RESULTS: Biological assays showed adequate cell metabolic activity and cell migration in BRF, while SEM assay evidenced that TFbc and BRF groups demonstrated a superior cell adhesion process, including substrate adhesion, cytoskeleton development, and spreading on the niche-like structures of the cement as compared to the AHP group. TFbc and BRF-treated groups exhibited a significantly lower IL6 and IL8 production than AHP (*â¯pâ¯<.05). The bioceramic sealers stimulated heightened expression of BSP, CEMP-1, and CAP genes within a 7-14â¯day period. Notably, BRF and TFbc demonstrated a significant enhancement in the mineralization of hPDLSCs when compared to the negative control. Among these, cells treated with BRF showed a more substantial accumulation of calcium (***â¯pâ¯<â¯.001). CONCLUSIONS: Taken together, these findings indicate that BRF can potentially enhance cell differentiation by promoting the expression of essential genes related to bone and cement formation. In addition, BRF and TFbc displayed anti-inflammatory effects.
Assuntos
Anti-Inflamatórios , Diferenciação Celular , Humanos , Diferenciação Celular/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Proliferação de Células/efeitos dos fármacos , Cerâmica/farmacologia , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Movimento Celular/efeitos dos fármacos , Adesão Celular/efeitos dos fármacosRESUMO
Whilst demonstrated extensively in vitro, the control of cell behaviour via modulation of substrate compliance in live tissues has not been accomplished to date. Here we propose that stem cells can be regulated solely through in situ modulation of tissue biomechanics. By first establishing, via high-resolution Brillouin spectro-microscopy, that the outer edge (limbus) of live human corneas has a substantially lower bulk modulus compared to their centre, we then demonstrate that this difference is associated with limbal epithelial stem cell (LESC) residence and YAP-dependent mechanotransduction. This phenotype-through-biomechanics correlation is further explored in vivo using a rabbit alkali burn model. Specifically, we show that treating the burnt surface of the cornea with collagenase effectively restores the tissue's mechanical properties and its capacity to support LESCs through mechanisms involving YAP suppression. Overall, these findings have extended implications for understanding stem cell niche biomechanics and its impact on tissue regeneration.
Assuntos
Córnea/citologia , Limbo da Córnea/citologia , Células-Tronco/citologia , Adulto , Idoso , Animais , Fenômenos Biomecânicos , Diferenciação Celular/fisiologia , Colagenases/farmacologia , Córnea/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/transplante , Humanos , Limbo da Córnea/efeitos dos fármacos , Limbo da Córnea/ultraestrutura , Mecanotransdução Celular , Microscopia de Fluorescência , Pessoa de Meia-Idade , Fenótipo , Coelhos , Nicho de Células-Tronco/efeitos dos fármacos , Nicho de Células-Tronco/fisiologia , Células-Tronco/efeitos dos fármacos , Engenharia Tecidual/métodos , Cicatrização/fisiologiaRESUMO
Biomanufacturing is a relatively new research domain focusing on the use of additive manufacturing technologies, biomaterials, cells and biomolecular signals to produce tissue constructs for tissue engineering. For bone regeneration, researchers are focusing on the use of polymeric and polymer/ceramic scaffolds seeded with osteoblasts or mesenchymal stem cells. However, the design of high-performance scaffolds in terms of mechanical, cell-stimulation and biological performance is still required. This is the first paper investigating the use of an extrusion additive manufacturing system to produce poly(ε-caprolactone) (PCL), PCL/graphene nanosheet (GNS) and PCL/carbon nanotube (CNT) scaffolds for bone applications. Scaffolds with regular and reproducible architecture were produced and evaluated from chemical, physical and biological points of view. Results suggest that the addition of both graphene and CNT allow the fabrication of scaffolds with improved properties. It also shows that scaffolds containing graphene present better mechanical properties and high cell-affinity improving cell attachment, proliferation and differentiation.
Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Nanotubos de Carbono/química , Poliésteres/química , Alicerces Teciduais/química , Tecido Adiposo/citologia , Adsorção , Proteínas Sanguíneas/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Teste de Materiais , Fenômenos Mecânicos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Engenharia TecidualRESUMO
It is of great interest to prepare osteogenic and antibacterial coatings for successful implants. Current coating techniques suffer from being time-consuming, substrate material or shape dependence, expensive equipment, environmental pollution, low stability, processes that are difficult to control, etc. Herein, inspired by mussels, we report a one-step and versatile method to fabricate a dual functional coating. The coating is finished in minutes independently of materials or dimensions of substrates. Thus, our coatings exhibit strong antibacterial ability against both Gram-positive bacteria S. aureus, and Gram-negative bacteria E. coli, support the proliferation of dental pulp stem cells (DPSCs), and are powerful for inducing osteogenic differentiation. The universality, facility, rapidness, and mildness of our coating process, which is also environmentally-friendly and cost-effective, points towards potential applications in bone or dental implants.
Assuntos
Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/síntese química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Animais , Bivalves , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Análise Custo-Benefício , Polpa Dentária/citologia , Humanos , Proteínas/química , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Propriedades de SuperfícieRESUMO
BACKGROUND: Chemical residues often have cytotoxic effects on the stem cells. This study aimed to assess the cytotoxic effects of intracanal medicaments on stem cells of the apical papilla (SCAPs) using methyl thiazolyl tetrazolium (MTT), trypan blue exclusion (TBE) and lactate dehydrogenase release (LDHR) assays. METHODS: SCAPs were cultured and exposed to 0.125, 0.25, 1, 5 and 10 mg/mL concentrations of modified triple antibiotic paste (mTAP)/distilled water (DW), mTAP/chlorhexidine (CHX), calcium hydroxide(Ca(OH)2)/CHX and Ca(OH)2/DW. Cell viability was quantitatively analyzed using the MTT, LDHR and TBE assays. Data were analyzed using one-way ANOVA and Tukey's test. RESULTS: All three assessment methods yielded the same results. Ca(OH)2/ DW resulted in the highest and mTAP/CHX resulted in the lowest cell viability. In contrast to Ca(OH)2, mTAP decreased cell viability in a dose-dependent manner. Also, addition of CHX to mTAP and Ca(OH)2 increased their cytotoxicity. CONCLUSIONS: In contrast to the proliferative effects of Ca(OH)2, even low concentrations of mTAP have cytotoxic effects on SCAPs.
Assuntos
Antibacterianos/toxicidade , Células-Tronco/efeitos dos fármacos , Ápice Dentário/citologia , Células Cultivadas , Humanos , L-Lactato Desidrogenase , Sais de Tetrazólio , Testes de Toxicidade , Azul TripanoRESUMO
The identification of biomaterials that modulate cell responses is a crucial task for tissue engineering and cell therapy. The identification of novel materials is complicated by the immense number of synthesizable polymers and the time required for testing each material experimentally. In the current study, polymeric biomaterial-cell interactions were assessed rapidly using a microarray format. The attachment, proliferation, and differentiation of human dental pulp stem cells (hDPSCs) were investigated on 141 homopolymers and 400 diverse copolymers. The copolymer of isooctyl acrylate and 2-(methacryloyloxy)ethyl acetoacetate achieved the highest attachment and proliferation of hDPSC, whereas high cell attachment and differentiation of hDPSC were observed on the copolymer of isooctyl acrylate and trimethylolpropane ethoxylate triacrylate. Computational models were generated, relating polymer properties to cellular responses. These models could accurately predict cell behavior for up to 95% of materials within a test set. The models identified several functional groups as being important for supporting specific cell responses. In particular, oxygen-containing chemical moieties, including fragments from the acrylate/acrylamide backbone of the polymers, promoted cell attachment. Small hydrocarbon fragments originating from polymer pendant groups promoted cell proliferation and differentiation. These computational models constitute a key tool to direct the discovery of novel materials within the enormous chemical space available to researchers.
Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Polpa Dentária/citologia , Polímeros/farmacologia , Células-Tronco/citologia , Diferenciação Celular/efeitos dos fármacos , Polpa Dentária/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Humanos , Teste de Materiais/métodos , Modelos Biológicos , Modelos Químicos , Odontogênese/efeitos dos fármacos , Células-Tronco/efeitos dos fármacosRESUMO
The objective of this study was to investigate the effects of a silicate-based composite material on proliferation and mineralization of human dental pulp cells (hDPCs), which was compared with those of calcium hydroxide (Ca(OH)2, CH) and tricalcium silicate (Ca3SiO5, C3S). HDPCs were cultured with CH, C3S and tricalcium silicate/dicalcium silicate (Ca3SiO5/Ca2SiO4, C3S/C2S) composites extract. The CCK-8 assay showed that the composite material stimulated the proliferation of hDPCs. The odontogenic marker genes and DSPP protein expression were more significantly up-regulated by the C3S/C2S composite material compared with pure CH and C3S. HDPCs cultured with composite material extract exert stronger ALP activity and alizarin red S staining. C3S/C2S composite material was advantageous over pure C3S by showing enhanced ability to stimulate the proliferation and odontogenic differentiation of hDPCs, suggesting that the C3S/C2S composite materials possess desirable biocompatibility and bioactivity, and might be a new type of pulp-capping agent and dentin alternative materials.
Assuntos
Compostos de Cálcio/farmacologia , Resinas Compostas/farmacologia , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Fosfatase Alcalina/biossíntese , Western Blotting , Hidróxido de Cálcio/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase em Tempo Real , Silicatos/farmacologia , Calcificação de Dente/efeitos dos fármacosRESUMO
The culture of mast cells from human tissues such a cord blood, peripheral blood or bone marrow aspirates has advanced our understanding of human mast cells (huMC) degranulation, mediator production and response to pharmacologic agents. However, existing methods for huMC culture tend to be laborious and expensive. Combining technical approaches from several of these protocols, we designed a simplified and more cost effective approach to the culture of mast cells from human cell populations including peripheral blood and cryopreserved cells from lymphocytapheresis. On average, we reduced by 30-50 fold the amount of culture media compared to our previously reported method, while the total MC number generated by this method (2.46±0.63×106 vs. 2.4±0.28×106, respectively, from 1.0×108 lymphocytapheresis or peripheral blood mononuclear blood cells [PBMCs]) was similar to our previous method (2.36±0.70×106), resulting in significant budgetary savings. In addition, we compared the yield of huMCs with or without IL-3 added to early cultures in the presence of stem cell factor (SCF) and interlukin-6 (IL-6) and found that the total MC number generated, while higher with IL-3 in the culture, did not reach statistical significance, suggesting that IL-3, often recommended in the culture of huMCs, is not absolutely required. We then performed a functional analysis by flow cytometry using standard methods and which maximized the data we could obtain from cultured cells. We believe these approaches will allow more laboratories to culture and examine huMC behavior going forward.
Assuntos
Antígenos CD34/metabolismo , Separação Celular/métodos , Leucaférese , Mastócitos/metabolismo , Células-Tronco/metabolismo , Antígenos CD34/imunologia , Biomarcadores/metabolismo , Orçamentos , Degranulação Celular , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Separação Celular/economia , Forma Celular , Células Cultivadas , Redução de Custos , Análise Custo-Benefício , Criopreservação , Meios de Cultura/metabolismo , Citometria de Fluxo , Humanos , Interleucina-3/farmacologia , Interleucina-6/farmacologia , Leucaférese/economia , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Fenótipo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptores de IgE/metabolismo , Fator de Células-Tronco/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/imunologia , Fatores de Tempo , Fluxo de TrabalhoAssuntos
Analgésicos Opioides/provisão & distribuição , Terapia Biológica , Biotecnologia , Empreendedorismo , Escherichia coli/metabolismo , Impressão Tridimensional , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Engenharia Tecidual , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/economia , Analgésicos Opioides/metabolismo , Animais , Bioengenharia , Reatores Biológicos , California , Diferenciação Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/economia , Avaliação Pré-Clínica de Medicamentos/métodos , Indústria Farmacêutica/tendências , Empreendedorismo/economia , Empreendedorismo/organização & administração , Escherichia coli/genética , Humanos , Investimentos em Saúde , Erros Inatos do Metabolismo/metabolismo , Erros Inatos do Metabolismo/terapia , Microbiota/genética , Microbiota/fisiologia , Distrofia Muscular de Duchenne/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Impressão Tridimensional/economia , Impressão Tridimensional/instrumentação , Pele , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismoRESUMO
PURPOSE: To assess the uptake, accumulation, temporal stability, and spatial localization of isoflurane (ISO) in the C57BL/6 mouse, and to identify its potential interference with the detection of labeled cardiac progenitor cells using 19 F MRI/MR spectroscopy (MRS). MATERIALS AND METHODS: Objectives are demonstrated using (a) in vitro ISO tests, (b) in vivo temporal accumulation/spatial localization C57BL/6 studies (n = 3), and (c) through injections of perfluoro-crown-ether (PFCE) labeled cardiac progenitor cells into femoral muscle areas of the murine hindlimb post-mortem (n = 1) using 1 H/19 F MRI/MRS at 9.4 Tesla. Data were acquired using double-gated spoiled gradient echo images and pulse-acquire spectra. For the in vivo study, the temporal stability of ISO resonances was quantified using coefficient of variability (CV) (5 min) estimates. RESULTS: Two ISO resonances were observed in vivo that correspond to the -CF3 and -OCHF2 moieties. CV values ranged between 3.2 and 6.4% (-CF3 ) and 6.4 and 11.2% (-OCHF2 ). Reductions of the ISO dose (2.0 to 1.7%) at 80 min postinduction had insignificant effects on ISO signals (P = 0.23; P = 0.71). PFCE-labeled cells exhibited a resonance at -16.25 ppm in vitro that did not overlap with the ISO resonances, a finding that is confirmed with MRS post-mortem using injected, labeled cells. Based on 19 F MRI, similar in vivo/post-mortem ISO compartmentalization was also confirmed in peripheral and thoracic skeletal muscles. CONCLUSION: Significant ISO accumulation was observed by 19 F MRS in vivo with temporally stable signals over 90 min postinduction. ISO effects on PFCE labels are anticipated to be minimal but may be more prominent for perfluoropolyether or perfluorooctyl bromide labels. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;45:1659-1667.
Assuntos
Artefatos , Rastreamento de Células/métodos , Éteres/farmacocinética , Fluorocarbonos/farmacocinética , Isoflurano/farmacocinética , Imageamento por Ressonância Magnética , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Células Cultivadas , Meios de Contraste , Radioisótopos de Flúor/farmacocinética , Isoflurano/farmacologia , Masculino , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Células-Tronco/efeitos dos fármacos , Distribuição TecidualRESUMO
AIM: To expand our understanding on the effect of magnetically actuated biomaterials in stem cells, inflammation and fibrous tissue growth. MATERIALS & METHODS: Magnetic biomaterials were obtained by doping iron oxide particles into starch poly-ϵ-caprolactone (SPCL) to create two formulations, magSPCL-1.8 and 3.6. Stem cell behavior was assessed in vitro and the inflammatory response, subcutaneously in Wistar rats. RESULTS: Metabolic activity and proliferation increased significantly overtime in SPCL and magSPCL-1.8. Electromagnetic fields attenuated the presence of mast cells and macrophages in tissues surrounding SPCL and magSPCL-1.8, between weeks 1 and 9. Macrophage reduction was more pronounced for magSPCL-1.8, which could explain why this material prevented growth of fibrous tissue overtime. CONCLUSION: Magnetically actuated biomaterials have potential to modulate inflammation and the growth of fibrous tissue.
Assuntos
Materiais Biocompatíveis/administração & dosagem , Inflamação/tratamento farmacológico , Nanopartículas de Magnetita/administração & dosagem , Tendões/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Campos Eletromagnéticos , Compostos Férricos/química , Humanos , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/efeitos da radiação , Nanopartículas de Magnetita/química , Ratos , Ratos Wistar , Células-Tronco/efeitos dos fármacos , Células-Tronco/efeitos da radiação , Tendões/crescimento & desenvolvimento , Tendões/patologia , Tendões/efeitos da radiaçãoRESUMO
Steatosis, also known as fatty liver disease (FLD), is a disorder in which the lipid metabolism of the liver is disturbed, leading to the abnormal retention of lipids in hepatocytes. FLD can be induced by several drugs, and although it is mostly asymptomatic, it can lead to steatohepatitis, which is associated with liver inflammation and damage. Drug-induced liver injury is currently the major cause of postmarketing withdrawal of pharmaceuticals and discontinuation of the development of new chemical entities. Therefore, the potential induction of steatosis must be evaluated during preclinical drug development. However, robust human-relevant in vitro models are lacking. In the present study, we explore the applicability of hepatic cells (hSKP-HPCs) derived from postnatal skin precursors, a stem cell population residing in human dermis, to investigate the steatosis-inducing effects of sodium valproate (Na-VPA). Exposure of hSKP-HPC to sub-cytotoxic concentrations of this reference steatogenic compound showed an increased intracellular accumulation of lipid droplets, and the modulation of key factors involved in lipid metabolism. Using a toxicogenomics approach, we further compared Na-VPA-treated hSKP-HPC and Na-VPA-treated primary human hepatocytes to liver samples from patients suffering from mild and advanced steatosis. Our data show that in hSKP-HPC exposed to Na-VPA and liver samples of patients suffering from mild steatosis, but not in primary human hepatocytes, "liver steatosis" was efficiently identified as a toxicological response. These findings illustrate the potential of hSKP-HPC as a human-relevant in vitro model to identify hepatosteatotic effects of chemical compounds.
Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Testes de Toxicidade/métodos , Ácido Valproico/toxicidade , Células Cultivadas , Citometria de Fluxo/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Pele/citologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , ToxicogenéticaRESUMO
Graphene-oxide (GO) and its most encountered derivatives, thermally reduced graphene oxide (TRGO) and nitrogen-doped graphene (N-Gr), were synthesized and structurally characterized by spectroscopic techniques, like Raman and (13)C MAS solid state NMR. Several biological effects (cytotoxicity, oxidative stress induction, and cellular and mithocondrial membrane alterations) induced by such graphene-based materials on human dental follicle stem cells were investigated. Graphene oxide shows the lowest cytotoxic effect, followed by the nitrogen-doped graphene, while thermally reduced graphene oxide exhibits high cytotoxic effects. Graphene oxide induces oxidative stress without causing cell membrane damage. Nitrogen-doped graphene shows a slight antioxidant activity; however, at high doses (20 and 40 µg/ml) it causes membrane damage. Both graphene oxide and nitrogen-doped graphene seem to be valuable candidates for usage in dental nanocomposites.
Assuntos
Grafite/química , Nanoestruturas , Células-Tronco/efeitos dos fármacos , Dente/efeitos dos fármacos , Humanos , Lactente , Microscopia Eletrônica de Transmissão , Células-Tronco/citologia , Dente/citologiaRESUMO
Industrial sectors perform toxicological assessments of their potential products to ensure human safety and to fulfill regulatory requirements. These assessments often involve animal testing, but ethical, cost, and time concerns, together with a ban on it in specific sectors, make appropriate in vitro systems indispensable in toxicology. In this study, we summarize the outcome of an EPAA (European Partnership of Alternatives to Animal Testing)-organized workshop on the use of stem cell-derived (SCD) systems in toxicology, with a focus on industrial applications. SCD systems, in particular, induced pluripotent stem cell-derived, provide physiological cell culture systems of easy access and amenable to a variety of assays. They also present the opportunity to apply the vast repository of existing nonclinical data for the understanding of in vitro to in vivo translation. SCD systems from several toxicologically relevant tissues exist; they generally recapitulate many aspects of physiology and respond to toxicological and pharmacological interventions. However, focused research is necessary to accelerate implementation of SCD systems in an industrial setting and subsequent use of such systems by regulatory authorities. Research is required into the phenotypic characterization of the systems, since methods and protocols for generating terminally differentiated SCD cells are still lacking. Organotypical 3D culture systems in bioreactors and microscale tissue engineering technologies should be fostered, as they promote and maintain differentiation and support coculture systems. They need further development and validation for their successful implementation in toxicity testing in industry. Analytical measures also need to be implemented to enable compound exposure and metabolism measurements for in vitro to in vivo extrapolation. The future of SCD toxicological tests will combine advanced cell culture technologies and biokinetic measurements to support regulatory and research applications. However, scientific and technical hurdles must be overcome before SCD in vitro methods undergo appropriate validation and become accepted in the regulatory arena.
Assuntos
Técnicas de Cultura/métodos , Células-Tronco/efeitos dos fármacos , Toxicologia/métodos , Animais , Ensaio de Unidades Formadoras de Colônias/métodos , Humanos , Células-Tronco/citologia , Células-Tronco/metabolismoRESUMO
Originator GCSF (Neupogen) has been used to mobilize progenitor stem cells and treat therapy-induced neutropenia in Canadian stem cell transplant settings for years. Although its benefit is not in question, viable alternatives are available. Biosimilar GCSF (Zarzio) is widely in use in Europe since 2009 and was recently approved in the U.S.for the same five indications as Neupogen. Zarzio is reported as safe, equally efficacious, more accessible and cost effective without negatively impacting patient outcomes. This paper summarizes the supporting evidence.
Assuntos
Medicamentos Biossimilares/uso terapêutico , Ensaios Clínicos como Assunto , Filgrastim/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neutropenia/tratamento farmacológico , Neutropenia/etiologia , Células-Tronco/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Medicamentos Biossimilares/economia , Canadá , Europa (Continente) , Feminino , Filgrastim/economia , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco/fisiologia , Estados Unidos , Adulto JovemRESUMO
The current study aimed to investigate adipose tissue-derived stem cells (ADSCs) in vivo by multimodality imaging following implantation for cellular therapy. The biological characteristics of ADSCs co-labeled with Molday ION Rhodamine B™ (MIRB) and green fluorescent protein (GFP) were studied in vitro. Following rat ADSC isolation and culture, a combined labeling strategy for ADSCs based on genetic modification of the reporter gene GFP with lentiviral vector expression enhancement and physical MIRB labeling was performed. Cell viability, proliferation, membrane-bound antigens and multiple differentiation ability were compared between the labeled and unlabeled ADSCs. The ADSCs were successfully labeled with GFP and MIRB, showing various fluorescent colors for marker identification. The fluorescence emitted by the GFP protein was sustained and exhibited stable expression, while MIRB fluorescence decreased with time. Compared with the unlabeled ADSCs, no significant differences were detected in cell viability, proliferation, membrane-bound antigens and multiple differentiation ability in the co-labeled samples (P>0.05). No significant effects on the biophysical properties of ADSCs were observed following co-labeling with lentiviral vectors encoding the gene for emerald green fluorescent protein and MIRB. The ADSCs were able to be efficiently tracked in vitro and in vivo by multimodality imaging thus, the co-labeling approach provides a novel strategy for therapeutic gene studies.
Assuntos
Tecido Adiposo/citologia , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Rastreamento de Células/métodos , Óxido Ferroso-Férrico/farmacocinética , Proteínas de Fluorescência Verde/metabolismo , Rodaminas/farmacocinética , Células-Tronco/citologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Fluorescência , Corantes Fluorescentes/farmacocinética , Técnicas In Vitro , Nanopartículas de Magnetita/química , Masculino , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Distribuição TecidualAssuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Miócitos Cardíacos/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Animais , Diferenciação Celular , Descoberta de Drogas/economia , Avaliação Pré-Clínica de Medicamentos/economia , Humanos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismoRESUMO
The present study aims to develop a new stem cell based gene delivery system consisting of human adipose tissue derived stem cells (hASCs) genetically modified with self-assembled nanocomplex of recombinant baculovirus and PAMAM dendrimer (Bac-PAMAM) to overexpress the vascular endothelial growth factor (VEGF). Cells were enveloped into branched PEG surface functionalized polymeric microcapsules for efficient transplantation. In vitro analysis confirmed efficient transduction of hASCs expressing 7.65 ± 0.86 ng functionally active VEGF per 10(6) microencapsulated hASCs (ASC-VEGF). To determine the potential of the developed system, chronically infarcted rat hearts were treated with either empty microcapsules (MC), microencapsulated hASCs expressing MGFP reporter protein (MC+ASC-MGFP), or MC+ASC-VEGF, and analyzed for 10 weeks. Post-transplantation data confirmed higher myocardial VEGF expressions with significantly enhanced neovasculature in the MC+ASC-VEGF group. In addition, the cardiac performance, as measured by percentage ejection fraction, also improved significantly in the MC+ASC-VEGF group (48.6 ± 6.1%) compared to that in MC+ASC-MGFP (38.8 ± 5.3%) and MC groups (31.5 ± 3.3%). Collectively, these data demonstrate the feasibility of this system for improved stem cell therapy applications.