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1.
Nat Mater ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977883

RESUMO

Despite the potential of oral immunotherapy against food allergy, adverse reactions and loss of desensitization hinder its clinical uptake. Dysbiosis of the gut microbiota is implicated in the increasing prevalence of food allergy, which will need to be regulated to enable for an effective oral immunotherapy against food allergy. Here we report an inulin gel formulated with an allergen that normalizes the dysregulated ileal microbiota and metabolites in allergic mice, establishes allergen-specific oral tolerance and achieves robust oral immunotherapy efficacy with sustained unresponsiveness in food allergy models. These positive outcomes are associated with enhanced allergen uptake by antigen-sampling dendritic cells in the small intestine, suppressed pathogenic type 2 immune responses, increased interferon-γ+ and interleukin-10+ regulatory T cell populations, and restored ileal abundances of Eggerthellaceae and Enterorhabdus in allergic mice. Overall, our findings underscore the therapeutic potential of the engineered allergen gel as a suitable microbiome-modulating platform for food allergy and other allergic diseases.

2.
Appl Microbiol Biotechnol ; 108(1): 11, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38159122

RESUMO

Pectobacterium spp. are necrotrophic plant pathogens that cause the soft rot disease in Chinese cabbage, resulting in severe yield loss. The use of conventional antimicrobial agents, copper-based bactericides, and antibiotics has encountered several limitations, such as bioaccumulation on plants and microbial resistance. Bacteriophages (phages) are considered promising alternative antimicrobial agents against diverse phytopathogens. In this study, we isolated and characterized two virulent phages (phiPccP-2 and phiPccP-3) to develop a phage cocktail. Morphological and genomic analyses revealed that two phages belonged to the Tevenvirinae and Mccorquodalevirinae subfamilies, respectively. The phiPccP-2 and phiPccP-3 phages, which have a broad host range, were stable at various environmental conditions, such as various pHs and temperatures and exposure to ultraviolet light. The phage cocktail developed using these two lytic phages inhibited the emergence of phage-resistant bacteria compared to single-phage treatments in in vitro challenge assays. The phage cocktail treatment effectively prevented the development of soft rot symptom in matured Chinese cabbage leaves. Additionally, the phage cocktail comprising three phages (phiPccP-1, phiPccP-2, and phiPccP-3) showed superior biocontrol efficacy against the mixture of Pectobacterium strains in Chinese cabbage seedlings. These results suggest that developing phage cocktails is an effective approach for biocontrol of soft rot disease caused by Pectobacterium strains in crops compared to single-phage treatments. KEY POINTS: •Two newly isolated Pectobacterium phages, phiPccP-2 and phiPccP-3, infected diverse Pectobacterium species and effectively inhibited the emergence of phage-resistant bacteria. •Genomic and physiological analyses suggested that both phiPccP-2 and phiPccP-3 are lytic phages and that their lytic activities are stable in the environmental conditions under which Chinese cabbage grows. •Treatment using a phage cocktail comprising phiPccP-2 and phiPccP-3 efficiently suppressed soft rot disease in detached mature leaves and seedlings of Chinese cabbage, indicating the applicability of the phage cocktail as an alternative antimicrobial agent.


Assuntos
Anti-Infecciosos , Bacteriófagos , Brassica , Pectobacterium , Bacteriófagos/fisiologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Bactérias
3.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923587

RESUMO

A lower-limb exoskeleton robot identifies the wearer's walking intention and assists the walking movement through mechanical force; thus, it is important to be able to identify the wearer's movement in real-time. Measurement of the angle of the knee and ankle can be difficult in the case of patients who cannot move the lower-limb joint properly. Therefore, in this study, the knee angle as well as the angles of the talocrural and subtalar joints of the ankle were estimated during walking by applying the neural network to two inertial measurement unit (IMU) sensors attached to the thigh and shank. First, for angle estimation, the gyroscope and accelerometer data of the IMU sensor were obtained while walking at a treadmill speed of 1 to 2.5 km/h while wearing an exoskeleton robot. The weights according to each walking speed were calculated using a neural network algorithm programmed in MATLAB software. Second, an appropriate weight was selected according to the walking speed through the IMU data, and the knee angle and the angles of the talocrural and subtalar joints of the ankle were estimated in real-time during walking through a feedforward neural network using the IMU data received in real-time. We confirmed that the angle estimation error was accurately estimated as 1.69° ± 1.43 (mean absolute error (MAE) ± standard deviation (SD)) for the knee joint, 1.29° ± 1.01 for the talocrural joint, and 0.82° ± 0.69 for the subtalar joint. Therefore, the proposed algorithm has potential for gait rehabilitation as it addresses the difficulty of estimating angles of lower extremity patients using torque and EMG sensors.


Assuntos
Exoesqueleto Energizado , Robótica , Articulação Talocalcânea , Tornozelo , Articulação do Tornozelo , Fenômenos Biomecânicos , Marcha , Humanos , Articulação do Joelho , Extremidade Inferior , Redes Neurais de Computação , Caminhada
4.
Int J Mol Sci ; 21(23)2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255398

RESUMO

Adipose-derived mesenchymal stromal cells (Ad-MSCs) are a promising tool for articular cartilage repair and regeneration. However, the terminal hypertrophic differentiation of Ad-MSC-derived cartilage is a critical barrier during hyaline cartilage regeneration. In this study, we investigated the role of matrilin-3 in preventing Ad-MSC-derived chondrocyte hypertrophy in vitro and in an osteoarthritis (OA) destabilization of the medial meniscus (DMM) model. Methacrylated hyaluron (MAHA) (1%) was used to encapsulate and make scaffolds containing Ad-MSCs and matrilin-3. Subsequently, the encapsulated cells in the scaffolds were differentiated in chondrogenic medium (TGF-ß, 1-14 days) and thyroid hormone hypertrophic medium (T3, 15-28 days). The presence of matrilin-3 with Ad-MSCs in the MAHA scaffold significantly increased the chondrogenic marker and decreased the hypertrophy marker mRNA and protein expression. Furthermore, matrilin-3 significantly modified the expression of TGF-ß2, BMP-2, and BMP-4. Next, we prepared the OA model and transplanted Ad-MSCs primed with matrilin-3, either as a single-cell suspension or in spheroid form. Safranin-O staining and the OA score suggested that the regenerated cartilage morphology in the matrilin-3-primed Ad-MSC spheroids was similar to the positive control. Furthermore, matrilin-3-primed Ad-MSC spheroids prevented subchondral bone sclerosis in the mouse model. Here, we show that matrilin-3 plays a major role in modulating Ad-MSCs' therapeutic effect on cartilage regeneration and hypertrophy suppression.


Assuntos
Cartilagem Hialina/crescimento & desenvolvimento , Hipertrofia/genética , Células-Tronco Mesenquimais/citologia , Osteoartrite/genética , Animais , Proteína Morfogenética Óssea 2/genética , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrogênese/genética , Humanos , Ácido Hialurônico/farmacologia , Hipertrofia/patologia , Hipertrofia/prevenção & controle , Hipertrofia/terapia , Proteínas Matrilinas/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Osteoartrite/terapia , Regeneração/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Alicerces Teciduais , Fator de Crescimento Transformador beta/genética
5.
Int J Mol Sci ; 21(12)2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32560070

RESUMO

Tauroursodeoxycholic acid (TUDCA) is a US FDA-approved hydrophilic bile acid for the treatment of chronic cholestatic liver disease. In the present study, we investigate the effects of TUDCA on the proliferation and differentiation of osteoblasts and its therapeutic effect on a mice model of osteoporosis. Following treatment with different concentrations of TUDCA, cell viability, differentiation, and mineralization were measured. Three-month-old female C57BL/6 mice were randomly divided into three groups (n = 8 mice per group): (i) normal mice as the control group, (ii) ovariectomy (OVX) group (receiving phosphate-buffered saline (PBS) treatment every other day for 4 weeks), and (iii) OVX group with TUDCA (receiving TUDCA treatment every other day for 4 weeks starting 6 weeks after OVX). At 11 weeks post-surgery, serum levels of procollagen type I N-terminal propeptides (PINP) and type I collagen crosslinked C-telopeptides (CTX) were measured, and all mice were sacrificed to examine the distal femur by micro-computed tomography (CT) scans and histology. TUDCA (100 nM, 1 µM) significantly increased the proliferation and viability of osteoblasts and osteoblast differentiation and mineralization when used in vitro. Furthermore, TUDCA neutralized the detrimental effects of methylprednisolone (methylprednisolone-induced osteoblast apoptosis). In the TUDCA treatment group the PINP level was higher and the CTX level was lower, but these levels were not significantly different compared to the PBS treatment group. Micro-CT and histology showed that the TUDCA treatment group preserved more trabecular structures in the distal femur compared to the PBS treatment group. In addition, the TUDCA treatment group increased the percentage bone volume with respect to the total bone volume, bone mineral density, and mice distal femur trabeculae compared with the PBS treatment group. Taken together, our findings suggest that TUDCA may provide a favorable effect on bones and could be used for the prevention and treatment of osteoporosis.


Assuntos
Osteoporose/tratamento farmacológico , Ovariectomia/efeitos adversos , Fragmentos de Peptídeos/metabolismo , Pró-Colágeno/metabolismo , Ácido Tauroquenodesoxicólico/administração & dosagem , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Metilprednisolona/efeitos adversos , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoporose/etiologia , Osteoporose/metabolismo , Distribuição Aleatória , Ácido Tauroquenodesoxicólico/farmacologia , Resultado do Tratamento
6.
J Prosthet Dent ; 123(6): 850-859, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31590981

RESUMO

STATEMENT OF PROBLEM: Patients with partial tooth loss treated with implant-supported fixed partial dentures (FPDs) have difficulty using conventional mandibular advancement devices (MADs) because of the risk of side effects. Also, which design factors affect biomechanical stability when designing MADs with better stability is unclear. PURPOSE: The purpose of this finite element (FE) analysis study was to analyze the effect of the MAD design on biomechanical behavior and to propose a new design process for improving the stability of MADs. MATERIAL AND METHODS: Each 3D model consisted of the maxillofacial bones, teeth, and implant-supported FPDs located in the left tooth loss area from the first premolar to the second molar and a MAD. Three types of custom-made MADs were considered: a complete-coverage MAD covering natural tooth-like conventional MADs, a shortened MAD excluding the coverage on the implant-supported FPD, and a newly designed MAD without anterior coverage. For the new MAD design, topology optimization was conducted to reduce the stress exerted on the teeth and to improve retention of the MAD. The new MAD design was finished by excluding the coverage of the maxillary and mandibular central incisors based on the results of the topology optimization. A mandibular posterior restorative force for a protrusion amount of 40% was used as the loading condition. The principal stress and pressure of the cancellous bone and periodontal ligaments (PDLs) were identified. RESULTS: Considering the load concentration induced by the complete-coverage MAD, bone resorption risk and root resorption risk were observed at both ends of the mandibular teeth. The shortened MAD resulted in the highest stress concentration and pressure with the worst stability. However, in the case of the complete-coverage MAD, the pressure in the PDLs was reduced to the normal range, and the risk of root resorption was reduced. CONCLUSIONS: For patients with implant-supported FPDs, MAD designs with different extents of coverage had an influence on biomechanical behavior in terms of stress distribution in cancellous bone and PDLs. A MAD design without anterior coverage provided improved stability compared with complete-coverage or shortened designs. The presented method for MAD design, which combined FE analysis and topology optimization, could be effectively applied in the design of such improved MADs.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Prótese Parcial Fixa , Análise de Elementos Finitos , Humanos , Placas Oclusais
7.
Adv Exp Med Biol ; 1064: 147-160, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30471031

RESUMO

Stem cells proliferate by undergoing self-renewal and differentiate into multiple cell lineages in response to biochemical and biophysical stimuli. Various biochemical cues such as growth factors, nucleic acids, chemical reagents, and small molecules have been used to induce stem cell differentiation or reprogramming or to maintain their pluripotency. Moreover, biophysical cues such as matrix stiffness, substrate topography, and external stress and strain play a major role in modulating stem cell behavior. In this chapter, we have summarized microenvironmental regulation of stem cell behavior through biochemical and biophysical stimulation.


Assuntos
Linhagem da Célula , Nicho de Células-Tronco , Células-Tronco/citologia , Diferenciação Celular , Reprogramação Celular , Humanos
8.
Int J Mol Sci ; 19(8)2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30049973

RESUMO

Regenerative medicine is an emerging discipline aimed at repairing and reestablishing the normal functions of tissues and organs damaged by aging, disease, injury, or congenital disorders.[...].


Assuntos
Nanomedicina/métodos , Medicina Regenerativa/métodos , Animais , Humanos , Nanotecnologia/métodos , Engenharia Tecidual/métodos
9.
Int J Mol Sci ; 19(4)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29649133

RESUMO

Capsular contracture, which is the pathologic development of fibrous capsules around implants, is a major complication of reconstructive and aesthetic breast surgeries. Capsular contracture can cause implant failure with breast hardening, deformity, and severe pain. The exact mechanisms underlying this complication remain unclear. In addition, anaplastic large cell lymphoma is now widely recognized as a very rare disease associated with breast implants. Foreign body reactions are an inevitable common denominator of capsular contracture. A number of studies have focused on the associated immune responses and their regulation. The present article provides an overview of the currently available techniques, including novel nano/microtechniques, to reduce silicone implant-induced contracture and associated foreign body responses.


Assuntos
Implantes de Mama/efeitos adversos , Contratura Capsular em Implantes/prevenção & controle , Linfoma Anaplásico de Células Grandes/prevenção & controle , Géis de Silicone/efeitos adversos , Animais , Materiais Biomiméticos/uso terapêutico , Feminino , Reação a Corpo Estranho/induzido quimicamente , Reação a Corpo Estranho/imunologia , Reação a Corpo Estranho/prevenção & controle , Humanos , Contratura Capsular em Implantes/induzido quimicamente , Contratura Capsular em Implantes/imunologia , Linfoma Anaplásico de Células Grandes/induzido quimicamente , Linfoma Anaplásico de Células Grandes/imunologia , Nanotecnologia
10.
Int J Mol Sci ; 19(2)2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29425184

RESUMO

Adipose-derived stem cells (ADSCs) have the potential to treat ischemic diseases. In general, ADSCs facilitate angiogenesis by secreting various pro-angiogenic growth factors. However, transplanted ADSCs have a low therapeutic efficacy in ischemic tissues due to their poor engraftment and low viability. Stromal cell-derived factor-1α (SDF-1α) improves the survival rate of stem cells transplanted into ischemic regions. In this study, we developed acid-degradable poly(ethylene glycol)-poly(amino ketal) (PEG-PAK)-based micelles for efficient intracellular delivery of SDF-1α plasmid DNA. The SDF-1α gene was successfully delivered into human ADSCs (hADSCs) using PEG-PAK micelles. Transfection of SDF-1α increased SDF-1α, vascular endothelial growth factor, and basic fibroblast growth factor gene expression and decreased apoptotic activity in hADSCs cultured under hypoxic conditions in comparison with conventional gene transfection using polyethylenimine. SDF-1α-transfected hADSCs also showed significantly increased SDF-1α and VEGF expression together with reduced apoptotic activity at 4 weeks after transplantation into mouse ischemic hindlimbs. Consequently, these cells improved angiogenesis in ischemic hindlimb regions. These PEG-PAK micelles may lead to the development of a novel therapeutic modality for ischemic diseases based on an acid-degradable polymer specialized for gene delivery.


Assuntos
Quimiocina CXCL12/genética , Técnicas de Transferência de Genes , Terapia Genética/métodos , Isquemia/terapia , Micelas , Neovascularização Fisiológica , Animais , Apoptose , Plásticos Biodegradáveis/química , Células Cultivadas , Quimiocina CXCL12/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Membro Posterior/irrigação sanguínea , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Polietilenoglicóis/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Int J Mol Sci ; 18(4)2017 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-28441755

RESUMO

Advances in mesenchymal stem cells (MSCs) and cell replacement therapies are promising approaches to treat cartilage and bone defects since substantial differentiation capacities of MSCs match the demands of tissue regeneration. Our understanding of the dynamic process requiring indispensable differentiation of MSCs remains limited. Herein, we describe the role of RHEB (Ras homolog enriched in brain) regulating gene signature for differentiation of human adipose derived mesenchymal stem cells (ASCs) into chondrogenic, osteogenic, and adipogenic lineages. RHEB-overexpression increases the proliferation of the ASCs. RHEB enhances the chondrogenic differentiation of ASCs in 3D culture via upregulation of SOX9 with concomitant increase in glycosaminoglycans (GAGs), and type II collagen (COL2). RHEB increases the osteogenesis via upregulation of runt related transcription factor 2 (RUNX2) with an increase in the calcium and phosphate contents. RHEB also increases the expression of osteogenic markers, osteonectin and osteopontin. RHEB knockdown ASCs were incapable of expressing sufficient SRY (Sex determining region Y)-box 9 (SOX9) and RUNX2, and therefore had decreased chondrogenic and osteogenic differentiation. RHEB-overexpression impaired ASCs differentiation into adipogenic lineage, through downregulation of CCAAT/enhancer binding protein beta (C/EBPß). Conversely, RHEB knockdown abolished the negative regulation of adipogenesis. We demonstrate that RHEB is a novel regulator, with a critical role in ASCs lineage determination, and RHEB-modulated ASCs may be useful as a cell therapy for cartilage and bone defect treatments.


Assuntos
Osso e Ossos/fisiologia , Cartilagem/fisiologia , Células-Tronco Mesenquimais/citologia , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Regeneração/fisiologia , Adipogenia , Tecido Adiposo/citologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Cartilagem/citologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Condrogênese , Colágeno Tipo II/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Osteogênese , Proteína Enriquecida em Homólogo de Ras do Encéfalo/antagonistas & inibidores , Proteína Enriquecida em Homólogo de Ras do Encéfalo/genética , Fatores de Transcrição SOX9/metabolismo
12.
Int J Mol Sci ; 18(11)2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29112123

RESUMO

Expansion of chondrocytes for repair of articular cartilage can lead to dedifferentiation, making it difficult to obtain a sufficient quantity of chondrocytes. Although previous studies have suggested that culture in a three-dimensional environment induces redifferentiation of dedifferentiated chondrocytes, its underlying mechanisms are still poorly understood in terms of metabolism compared with a two-dimensional environment. In this study, we demonstrate that attenuation of transglutaminase 2 (TG2), a multifunctional enzyme, stimulates redifferentiation of dedifferentiated chondrocytes. Fibroblast-like morphological changes increased as TG2 expression increased in passage-dependent manner. When dedifferentiated chondrocytes were cultured in a pellet culture system, TG2 expression was reduced and glycolytic enzyme expression up-regulated. Previous studies demonstrated that TG2 influences energy metabolism, and impaired glycolytic metabolism causes chondrocyte dedifferentiation. Interestingly, TG2 knockdown improved chondrogenic gene expression, glycolytic enzyme expression, and lactate production in a monolayer culture system. Taken together, down-regulation of TG2 is involved in redifferentiaton of dedifferentiated chondrocytes through enhancing glucose metabolism.


Assuntos
Diferenciação Celular/fisiologia , Condrócitos/citologia , Condrócitos/metabolismo , Condrogênese/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Glucose/metabolismo , Transglutaminases/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Condrogênese/genética , Metabolismo Energético/genética , Metabolismo Energético/fisiologia , Proteínas de Ligação ao GTP/genética , Humanos , Proteína 2 Glutamina gama-Glutamiltransferase , Transglutaminases/genética
13.
Int J Mol Sci ; 17(4)2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27104523

RESUMO

The extracellular matrix (ECM) of cartilage performs essential functions in differentiation and chondroprogenitor cell maintenance during development and regeneration. Here, we discuss the vital role of matrilin-3, an ECM protein involved in cartilage development and potential osteoarthritis pathomechanisms. As an adaptor protein, matrilin-3 binds to collagen IX to form a filamentous network around cells. Matrilin-3 is an essential component during cartilage development and ossification. In addition, it interacts directly or indirectly with transforming growth factor ß (TGF-ß), and bone morphogenetic protein 2 (BMP2) eventually regulates chondrocyte proliferation and hypertrophic differentiation. Interestingly, matrilin-3 increases interleukin receptor antagonists (IL-Ra) in chondrocytes, suggesting its role in the suppression of IL-1ß-mediated inflammatory action. Matrilin-3 downregulates the expression of matrix-degrading enzymes, such as a disintegrin metalloproteinase with thrombospondin motifs 4 (ADAMTS4) and ADAMTS5, matrix metalloproteinase 13 (MMP13), and collagen X, a hypertrophy marker during development and inflammatory conditions. Matrilin-3 essentially enhances collagen II and aggrecan expression, which are required to maintain the tensile strength and elasticity of cartilage, respectively. Interestingly, despite these attributes, matrilin-3 induces osteoarthritis-associated markers in chondrocytes in a concentration-dependent manner. Existing data provide insights into the critical role of matrilin-3 in inflammation, matrix degradation, and matrix formation in cartilage development and osteoarthritis.


Assuntos
Cartilagem/crescimento & desenvolvimento , Proteínas Matrilinas/fisiologia , Osteoartrite/metabolismo , Animais , Cartilagem/metabolismo , Diferenciação Celular , Condrócitos/citologia , Condrócitos/metabolismo , Condrogênese , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiologia , Proteínas Matrilinas/genética , Proteínas Matrilinas/metabolismo , Camundongos , Modelos Biológicos , Osteogênese
14.
Int J Mol Sci ; 17(6)2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27322256

RESUMO

Human adipose-derived stem cells (hASCs) have a capacity to undergo adipogenic, chondrogenic, and osteogenic differentiation. Recently, hASCs were applied to various fields including cell therapy for tissue regeneration. However, it is hard to predict the direction of differentiation of hASCs in real-time. Matrix metalloproteinases (MMPs) are one family of proteolytic enzymes that plays a pivotal role in regulating the biology of stem cells. MMPs secreted by hASCs are expected to show different expression patterns depending on the differentiation state of hASCs because biological functions exhibit different patterns during the differentiation of stem cells. Here, we investigated proteolytic enzyme activity, especially MMP-2 activity, in hASCs during their differentiation. The activities of proteolytic enzymes and MMP-2 were higher during chondrogenic differentiation than during adipogenic and osteogenic differentiation. During chondrogenic differentiation, mRNA expression of MMP-2 and the level of the active form of MMP-2 were increased, which also correlated with Col II. It is concluded that proteolytic enzyme activity and the level of the active form of MMP-2 were increased during chondrogenic differentiation, which was accelerated in the presence of Col II protein. According to our findings, MMP-2 could be a candidate maker for real-time detection of chondrogenic differentiation of hASCs.


Assuntos
Tecido Adiposo/citologia , Diferenciação Celular , Condrócitos/citologia , Metaloproteinase 2 da Matriz/metabolismo , Células-Tronco Mesenquimais/metabolismo , Tecido Adiposo/metabolismo , Biomarcadores/metabolismo , Células Cultivadas , Condrócitos/metabolismo , Humanos , Metaloproteinase 2 da Matriz/genética , Células-Tronco Mesenquimais/citologia
15.
Biochem Biophys Res Commun ; 450(2): 984-90, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-24971534

RESUMO

The epithelium-specific ETS transcription factor-1 (ESE-1) is physiologically important in the pathogenesis of various diseases. Recently, OCT4, a transcription factor involved in stem cell pluripotency, has been implicated in tumorigenesis. In this study, we invested the molecular mechanism by which ESE-1 regulates transcription of OCT4 in NCCIT human embryonic carcinoma cells. Real-time PCR analysis revealed that OCT4 levels were high in undifferentiated NCCIT cells but significantly decreased upon retinoic acid-mediated differentiation, concomitant with up-regulation of ESE-1 expression. OCT4 mRNA level rose following shRNA-mediated knockdown of ESE-1, but declined when ESE-1 was overexpressed, suggesting that the expression levels of OCT4 and ESE-1 may be coordinated in an opposite manner. Promoter-reporter assays revealed that induced OCT4 promoter activity in NCCIT cells was significantly down-regulated by ESE-1 overexpression in a dose-dependent manner. The inhibitory effect of ESE-1 on OCT4 promoter activity was relieved by co-expression of an ESE-1 mutant lacking the transactivation domain, but not by mutants lacking other domains. Serial deletion and site-directed mutagenesis of the OCT4 promoter revealed that a potential ETS binding site (EBS) is present in the conserved region 2 (CR2). ESE-1 interacted with the EBS element in CR2 and enrichment of CR2 significantly increased upon RA-mediated differentiation of NCCIT cells, suggesting that this binding is likely to be involved in ESE-1-mediated repression of OCT4 promoter activity upon differentiation. Taken together, the results of this study reveal the molecular details of the mechanism by which the oncogenic factor ESE-1 regulates expression of the stem cell transcription factor OCT4 in pluripotent NCCIT cells.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Células-Tronco de Carcinoma Embrionário/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/metabolismo , Proteínas Proto-Oncogênicas c-ets/metabolismo , Fatores de Transcrição/metabolismo , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Células-Tronco de Carcinoma Embrionário/citologia , Técnicas de Silenciamento de Genes , Humanos , Mutação , Células-Tronco Pluripotentes/citologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-ets/genética , Fatores de Transcrição/genética , Transcrição Gênica , Ativação Transcricional
16.
Carbohydr Polym ; 334: 122020, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553219

RESUMO

Zinc oxide nanostructures (ZnO NS) were fabricated in situ within a ternary hydrogel system composed of carboxymethyl cellulose-agarose-polyvinylpyrrolidone (CAP@ZnO TNCHs) by a one-pot method employing moist-heat solution casting. The percentages of CMC and ZnO NS were varied in the CAP hydrogel films and then they were investigated by different techniques, such as ATR/FTIR, TGA, XRD, XPS, and FE-SEM analysis. Furthermore, the mechanical properties, hydrophilicity, swelling, porosity, and antibacterial activity of the CAP@ZnO TNCHs were studied. In-vitro biocompatibility assays were performed with skin fibroblast (CCD-986sk) cells. In-vitro culture of CCD-986sk fibroblasts showed that the ZnO NS facilitated cell adhesion and proliferation. Furthermore, the application of CAP@ZnO TNCHs enhanced cellular interactions and physico-chemical, antibacterial bacterial, and biological performance relative to unmodified CAP hydrogels. Also, an in vivo wound healing study verified that the CAP@ZnO TNCHs promoted wound healing significantly within 18 days, an effect superior to that of unmodified CAP hydrogels. Hence, these newly developed cellulose-based ZnO TNCHs are promising materials for wound healing applications.


Assuntos
Nanoestruturas , Óxido de Zinco , Hidrogéis/farmacologia , Hidrogéis/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Carboximetilcelulose Sódica/química , Antibacterianos/química , Nanoestruturas/química , Cicatrização
17.
Bioact Mater ; 38: 331-345, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38764447

RESUMO

Cellular reprogramming technologies have been developed with different physicochemical factors to improve the reprogramming efficiencies of induced pluripotent stem cells (iPSCs). Ultrasound is a clinically applied noncontact biophysical factor known for regulating various cellular behaviors but remains uninvestigated for cellular reprogramming. Here, we present a new reprogramming strategy using low-intensity ultrasound (LIUS) to improve cellular reprogramming of iPSCs in vitro and in vivo. Under 3D microenvironment conditions, increased LIUS stimulation shows enhanced cellular reprogramming of the iPSCs. The cellular reprogramming process facilitated by LIUS is accompanied by increased mesenchymal to epithelial transition and histone modification. LIUS stimulation transiently modulates the cytoskeletal rearrangement, along with increased membrane fluidity and mobility to increase HA/CD44 interactions. Furthermore, LIUS stimulation with HA hydrogel can be utilized in application of both human cells and in vivo environment, for enhanced reprogrammed cells into iPSCs. Thus, LIUS stimulation with a combinatorial 3D microenvironment system can improve cellular reprogramming in vitro and in vivo environments, which can be applied in various biomedical fields.

18.
J Control Release ; 371: 386-405, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38844177

RESUMO

Recently, the formation of three-dimensional (3D) cell aggregates known as embryoid bodies (EBs) grown in media supplemented with HSC-specific morphogens has been utilized for the directed differentiation of embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), into clinically relevant hematopoietic stem cells (HSCs). However, delivering growth factors and nutrients have become ineffective in inducing synchronous differentiation of cells due to their 3D conformation. Moreover, irregularly sized EBs often lead to the formation of necrotic cores in larger EBs, impairing differentiation. Here, we developed two gelatin microparticles (GelMPs) with different release patterns and two HSC-related growth factors conjugated to them. Slow and fast releasing GelMPs were conjugated with bone morphogenic factor-4 (BMP-4) and stem cell factor (SCF), respectively. The sequential presentation of BMP-4 and SCF in GelMPs resulted in efficient and effective hematopoietic differentiation, shown by the enhanced gene and protein expression of several mesoderm and HSC-related markers, and the increased concentration of released HSC-related cytokines. In the present study, we were able to generate CD34+, CD133+, and FLT3+ cells with similar cellular and molecular morphology as the naïve HSCs that can produce colony units of different blood cells, in vitro.


Assuntos
Proteína Morfogenética Óssea 4 , Diferenciação Celular , Gelatina , Células-Tronco Hematopoéticas , Células-Tronco Pluripotentes Induzidas , Esferoides Celulares , Fator de Células-Tronco , Proteína Morfogenética Óssea 4/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator de Células-Tronco/metabolismo , Gelatina/química , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Animais , Humanos , Camundongos
19.
Bioeng Transl Med ; 9(2): e10629, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38435815

RESUMO

Human induced pluripotent stem cells (iPSCs) hold great promise for personalized medicine, as they can be differentiated into specific cell types, especially mesenchymal stem cells (MSCs). Therefore, our study sought to assess the feasibility of deriving MSCs from teratomas generated from human iPSCs. Teratomas serve as a model to mimic multilineage human development, thus enriching specific somatic progenitors and stem cells. Here, we discovered a small, condensed mass of MSCs within iPSC-generated teratomas. Afterward, we successfully isolated MSCs from this condensed mass, which was a byproduct of teratoma development. To evaluate the characteristics and cell behaviors of iPSC-derived MSCs (iPSC-MSCs), we conducted comprehensive assessments using qPCR, immunophenotype analysis, and cell proliferation-related assays. Remarkably, iPSC-MSCs exhibited an immunophenotype resembling that of conventional MSCs, and they displayed robust proliferative capabilities, similar to those of higher pluripotent stem cell-derived MSCs. Furthermore, iPSC-MSCs demonstrated the ability to differentiate into multiple lineages in vitro. Finally, we evaluated the therapeutic potential of iPSC-MSCs using an osteochondral defect model. Our findings demonstrated that teratomas are a promising source for the isolation of condensed MSCs. More importantly, our results suggest that iPSC-MSCs derived from teratomas possess the capacity for tissue regeneration, highlighting their promise for future therapeutic applications.

20.
Int J Biol Macromol ; 278(Pt 2): 134707, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39147339

RESUMO

Herein, we report for the first time a simple strategy to design a hierarchical chemically exfoliated magnesium diboride and guar gum network structure decorated with Ru nanoparticles (eMgB2-GG@Ru) as an electrode to evaluate its electrochemical performance for the application of supercapacitor. The eMgB2 and functionalized eMgB2-GG@Ru materials were thoroughly examined using XRD, TGA, DLS, FE-SEM, STEM, AFM, XPS, and BET techniques. The combined eMgB2-GG@Ru electrode exhibits a network structure morphology with an increased interlayer distance of eMgB2 nanolayers along with a uniform distribution of spherical Ru nanoparticles. The electrochemical performance of eMgB2-GG@Ru and its pristine materials was studied through CV, GCD, and EIS to determine their supercapacitor performance. The eMgB2-GG@Ru electrode demonstrates higher specific capacitance (352 F/g) than its eMgB2@Ru (258.9 F/g), and MgB2 (214.5 F/g) counterparts at a current density of 0.5 A/g in a three-electrode setup using 3 M KOH electrolyte. The hierarchical eMgB2-GG@Ru solid-state symmetric devices maintained higher capacity retention of 89 % even after 7000 cycles, achieving a maximum energy density of 26.12 kW/kg at the power density of 450 W/kg at 0.5 A/g. Therefore, the innovative eMgB2-GG@Ru electrode offers superior electrochemical performance with efficient electrolyte ion mobility for energy storage applications.


Assuntos
Capacitância Elétrica , Eletrodos , Galactanos , Mananas , Nanocompostos , Gomas Vegetais , Rutênio , Gomas Vegetais/química , Nanocompostos/química , Galactanos/química , Rutênio/química , Mananas/química , Técnicas Eletroquímicas , Compostos de Magnésio/química
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