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1.
Dent Mater J ; 42(3): 351-359, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-36775334

RESUMO

Senescence-associated secretory phenotype (SASPs) secreted from senescent cells often cause the deleterious damages to the surrounding tissues. Although dedifferentiated fat (DFAT) cells prepared are considered a promising cell source for regenerative therapies, SASPs from DFAT cells undergoing long-term cell culture, which latently induce replicative senescence, have barely been explored. The present study was designed to investigate senescent behaviors in rat-derived DFAT cells at high passage numbers and to analyze the possible types of SASPs. Our data show that DFAT cells undergo senescence during replicative passaging, as determined by multiple senescent hallmarks including morphological changes in cell shape and nucleus. Moreover, RT2 PCR array analysis indicated that senescent DFAT cells expressed higher levels of 16 inflammatory cytokines (Ccl11, Ccl12, Ccl21, Ccl5, Csf2, Cxcl1, Cxcl12, Ifna2, IL11, IL12a, IL13, IL1a, IL1rn, IL6, Mif, and Tnf) associated with SASPs than non-senescent cells. This study implicates that rat DFAT cells undergo cellular senescence after long-term cell culture; cautious consideration should be paid to treat SASP secretion when senescent DFAT cells are used in regenerative medicine.


Assuntos
Senescência Celular , Fenótipo Secretor Associado à Senescência , Ratos , Animais , Senescência Celular/genética , Adipócitos , Técnicas de Cultura de Células
2.
Int J Mol Sci ; 19(12)2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30501071

RESUMO

Cost-effective and functionalized scaffolds are in high demand for stem-cell-based regenerative medicine to treat refractory bone defects in craniofacial abnormalities and injuries. One potential strategy is to utilize pharmacological and cost-effective plant polyphenols and biocompatible proteins, such as gelatin. Nevertheless, the use of chemically modified proteins with plant polyphenols in this strategy has not been standardized. Here, we demonstrated that gelatin chemically modified with epigallocatechin gallate (EGCG), the major catechin isolated from green tea, can be a useful material to induce bone regeneration in a rat congenial cleft-jaw model in vivo when used with/without adipose-derived stem cells or dedifferentiated fat cells. Vacuum-heated gelatin sponges modified with EGCG (vhEGCG-GS) induced superior osteogenesis from these two cell types compared with vacuum-heated gelatin sponges (vhGS). The EGCG-modification converted the water wettability of vhGS to a hydrophilic property (contact angle: 110° to 3.8°) and the zeta potential to a negative surface charge; the modification enhanced the cell adhesion property and promoted calcium phosphate precipitation. These results suggest that the EGCG-modification with chemical synthesis can be a useful platform to modify the physicochemical property of gelatin. This alteration is likely to provide a preferable microenvironment for multipotent progenitor cells, inducing superior bone formation in vivo.


Assuntos
Catequina/análogos & derivados , Fissura Palatina/terapia , Gelatina/química , Gelatina/farmacologia , Tecido Adiposo/citologia , Animais , Catequina/química , Catequina/farmacologia , Desdiferenciação Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Microscopia Eletrônica de Varredura , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos , Medicina Regenerativa/métodos
3.
Molecules ; 23(4)2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29641458

RESUMO

Chemical modification of gelatin using epigallocatechin gallate (EGCG) promotes bone formation in vivo. However, further improvements are required to increase the mechanical strength and bone-forming ability of fabricated EGCG-modified gelatin sponges (EGCG-GS) for practical applications in regenerative therapy. In the present study, we investigated whether vacuum heating-induced dehydrothermal cross-linking of EGCG-GS enhances bone formation in critical-sized rat calvarial defects. The bone-forming ability of vacuum-heated EGCG-GS (vhEGCG-GS) and other sponges was evaluated by micro-computed tomography and histological staining. The degradation of sponges was assessed using protein assays, and cell morphology and proliferation were verified by scanning electron microscopy and immunostaining using osteoblastic UMR106 cells in vitro. Four weeks after the implantation of sponges, greater bone formation was detected for vhEGCG-GS than for EGCG-GS or vacuum-heated gelatin sponges (dehydrothermal cross-linked sponges without EGCG). In vitro experiments revealed that the relatively low degradability of vhEGCG-GS supports cell attachment, proliferation, and cell-cell communication on the matrix. These findings suggest that vacuum heating enhanced the bone forming ability of EGCG-GS, possibly via the dehydrothermal cross-linking of EGCG-GS, which provides a scaffold for cells, and by maintaining the pharmacological effect of EGCG.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Catequina/análogos & derivados , Gelatina/farmacologia , Crânio/lesões , Alicerces Teciduais/química , Animais , Catequina/química , Linhagem Celular , Proliferação de Células , Gelatina/química , Calefação , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Ratos , Medicina Regenerativa , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Engenharia Tecidual , Vácuo , Microtomografia por Raio-X
4.
Nihon Ronen Igakkai Zasshi ; 54(2): 165-171, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28592736

RESUMO

We have developed a cloud system, the e-Renraku Notebook (e-RN) for sharing of home care information based on the concept of "patient-centricity". In order to assess the likelihood that our system will enhance the communication and sharing of information between home healthcare staff members and home-care patients, we selected patients who were residing in mountainous regions for inclusion in our study. We herein report the findings.Eighteen staff members from 7 medical facilities and 9 patients participated in the present study.The e-RN was developed for two reasons: to allow patients to independently report their health status and to have staff members view and respond to the information received. The patients and staff members were given iPads with the pre-installed applications and the information being exchanged was reviewed over a 54-day period.Information was mainly input by the patients (61.6%), followed by the nurses who performed home visits (19.9%). The amount of information input by patients requiring high-level nursing care and their corresponding staff member was significantly greater than that input by patients who required low-level of nursing care.This patient-centric system in which patients can independently report and share information with a member of the healthcare staff provides a sense of security. It also allows staff members to understand the patient's health status before making a home visit, thereby giving them a sense of security and confidence. It was also noteworthy that elderly patients requiring high-level nursing care and their staff counterpart input information in the system significantly more frequently than patients who required low-level care.


Assuntos
Computação em Nuvem , Serviços de Assistência Domiciliar , Disseminação de Informação , Idoso , Altitude , Atenção à Saúde , Feminino , Humanos , Masculino
5.
Cancer Immunol Immunother ; 56(4): 555-62, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17031641

RESUMO

In order to study the effect of glycosylation on its biological activities and to develop tumor necrosis factor alpha (TNFalpha) with less deleterious effects, N-acetylneuraminic acid (NeuAc) with a C9 spacer was chemically coupled to human recombinant TNFalpha. NeuAc-coupled TNFalpha (NeuAc-TNFalpha) exhibited reduced activities in vitro by about threefold compared to native TNFalpha. In this study, we examined a variety of TNFalpha activities in vivo. NeuAc-TNFalpha reduced activities in the up-regulation of serum levels of IL-6 and NOx, but comparable activity as native TNFalpha in the down-regulation of the serum level of glucose. However, NeuAc-TNFalpha was more potent than TNFalpha in the up-regulation of the serum level of serum amyloid A (SAA). NeuAc-TNFalpha was less toxic to mice. In addition, NeuAc-TNFalpha exhibited an augmented anti-tumor activity against Meth-A fibrosarcoma without hemorrhagic necrosis. These results indicate that coupling with NeuAc enabled us to develop neoglycoTNFalpha with selective activities in vivo, including enhanced anti-tumor activity but reduced toxicity.


Assuntos
Fibrossarcoma/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/toxicidade , Fator de Necrose Tumoral alfa/metabolismo , Animais , Glicemia/análise , Ensaio de Imunoadsorção Enzimática , Feminino , Glicosilação , Humanos , Interleucina-6/sangue , Camundongos , Ácido N-Acetilneuramínico/toxicidade , Óxido Nítrico/sangue , Proteínas Recombinantes/síntese química , Proteína Amiloide A Sérica/análise , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/toxicidade
6.
Cancer Immunol Immunother ; 56(4): 545-53, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17031642

RESUMO

In order to study the effect of glycosylation on its biological activities, and to develop TNFalpha with less deleterious effects, recombinant human TNFalpha was chemically coupled with N-acetylneuraminic acid (NeuAc). NeuAc with C9 spacer was coupled to TNFalpha by acyl azide method. Two glycosylated TNFalphas, designated L NeuAc-TNFalpha and H NeuAc-TNFalpha, were purified by anion-exchange chromatography. NeuAc coupling to TNFalpha was confirmed by lectin blotting. Average number of carbohydrate molecules introduced per molecule of L NeuAc-TNFalpha and H NeuAc-TNFalpha were estimated to be 1.0 and 1.5, respectively. We examined a variety of TNFalpha activities in vitro, including antiproliferative or cytotoxic activities to tumor cells, proliferative effect on fibroblast cells, stimulatory effects on IL-6 production by melanoma cells and NF-kappaB activation in hepatoma cells. L NeuAc-TNFalpha and H NeuAc-TNFalpha exhibited reduced activities about 1/3 and 1/10 as compared to native TNFalpha in all the activities performed in vitro.


Assuntos
Ácido N-Acetilneuramínico/metabolismo , Proteínas Recombinantes/síntese química , Proteínas Recombinantes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Fibroblastos/metabolismo , Glicosilação , Humanos , Espectrometria de Massas , Camundongos , Ácido N-Acetilneuramínico/química , Fator de Necrose Tumoral alfa/química
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