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1.
PLoS One ; 14(9): e0220973, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536495

RESUMO

In breast cancer, tumor hypoxia has been linked to poor prognosis and increased metastasis. Hypoxia activates transcriptional programs in cancer cells that lead to increased motility and invasion, as well as various metabolic changes. One of these metabolic changes, an increase in glycogen metabolism, has been further associated with protection from reactive oxygen species damage that may lead to premature senescence. Here we report that breast cancer cells significantly increase glycogen stores in response to hypoxia. We found that knockdown of the brain isoform of an enzyme that catalyzes glycogen breakdown, glycogen phosphorylase B (PYGB), but not the liver isoform, PYGL, inhibited glycogen utilization in estrogen receptor negative and positive breast cancer cells; whereas both independently inhibited glycogen utilization in the normal-like breast epithelial cell line MCF-10A. Functionally, PYGB knockdown and the resulting inhibition of glycogen utilization resulted in significantly decreased wound-healing capability in MCF-7 cells and a decrease in invasive potential of MDA-MB-231 cells. Thus, we identify PYGB as a novel metabolic target with potential applications in the management and/or prevention of metastasis in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Glicogênio/metabolismo , Hipóxia/metabolismo , Fenótipo , Fosforilase b/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Redes e Vias Metabólicas , Metástase Neoplásica , Estadiamento de Neoplasias , Fosforilase b/genética , Isoformas de Proteínas , Interferência de RNA , RNA Interferente Pequeno/genética
2.
J Cell Sci ; 131(8)2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29588397

RESUMO

Defective endocytosis and vesicular trafficking of signaling receptors has recently emerged as a multifaceted hallmark of malignant cells. Clathrin-coated pits (CCPs) display highly heterogeneous dynamics on the plasma membrane where they can take from 20 s to over 1 min to form cytosolic coated vesicles. Despite the large number of cargo molecules that traffic through CCPs, it is not well understood whether signaling receptors activated in cancer, such as epidermal growth factor receptor (EGFR), are regulated through a specific subset of CCPs. The signaling lipid phosphatidylinositol (3,4,5)-trisphosphate [PI(3,4,5)P3], which is dephosphorylated by phosphatase and tensin homolog (PTEN), is a potent tumorigenic signaling lipid. By using total internal reflection fluorescence microscopy and automated tracking and detection of CCPs, we found that EGF-bound EGFR and PTEN are enriched in a distinct subset of short-lived CCPs that correspond with clathrin-dependent EGF-induced signaling. We demonstrated that PTEN plays a role in the regulation of CCP dynamics. Furthermore, increased PI(3,4,5)P3 resulted in higher proportion of short-lived CCPs, an effect that recapitulates PTEN deletion. Altogether, our findings provide evidence for the existence of short-lived 'signaling-capable' CCPs.


Assuntos
Invaginações Revestidas da Membrana Celular/metabolismo , Receptores ErbB/metabolismo , PTEN Fosfo-Hidrolase/genética , Humanos , Transdução de Sinais
3.
Bull Math Biol ; 80(5): 1310-1344, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28455685

RESUMO

The development of network inference methodologies that accurately predict connectivity in dysregulated pathways may enable the rational selection of patient therapies. Accurately inferring an intracellular network from data remains a very challenging problem in molecular systems biology. Living cells integrate extremely robust circuits that exhibit significant heterogeneity, but still respond to external stimuli in predictable ways. This phenomenon allows us to introduce a network inference methodology that integrates measurements of protein activation from perturbation experiments. The methodology relies on logic-based networks to provide a predictive approximation of the transfer of signals in a network. The approach presented was validated in silico with a set of test networks and applied to investigate the epidermal growth factor receptor signaling of a breast epithelial cell line, MFC10A. In our analysis, we predict the potential signaling circuitry most likely responsible for the experimental readouts of several proteins in the mitogen-activated protein kinase and phosphatidylinositol-3 kinase pathways. The approach can also be used to identify additional necessary perturbation experiments to distinguish between a set of possible candidate networks.


Assuntos
Modelos Biológicos , Transdução de Sinais , Algoritmos , Linhagem Celular , Simulação por Computador , Receptores ErbB/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Conceitos Matemáticos
4.
Sci Rep ; 6: 39190, 2016 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-27991524

RESUMO

Inflammatory breast cancer (IBC) is the most lethal form of breast cancer. All IBC patients have lymph node involvement and one-third of patients already have distant metastasis at diagnosis. This propensity for metastasis is a hallmark of IBC distinguishing it from less lethal non-inflammatory breast cancers (nIBC). Genetic profiling studies have been conducted to differentiate IBC from nIBC, but no IBC cancer-cell-specific gene signature has been identified. We hypothesized that a tumor-extrinsic factor, notably tumor-associated macrophages, promotes and contributes to IBC's extreme metastatic phenotype. To this end, we studied the effect of macrophage-conditioned media (MCM) on IBC. We show that two IBC cell lines are hyper-responsive to MCM as compared to normal-like breast and aggressive nIBC cell lines. We further interrogated IBC's hyper-responsiveness to MCM using a microfluidic migration device, which permits individual cell migration path tracing. We found the MCM "primes" the IBC cells' cellular machinery to become extremely migratory in response to a chemoattractant. We determined that interleukins -6, -8, and -10 within the MCM are sufficient to stimulate this enhanced IBC migration effect, and that the known metastatic oncogene, RhoC GTPase, is necessary for the enhanced migration response.


Assuntos
Neoplasias Inflamatórias Mamárias/patologia , Macrófagos/metabolismo , Proteína de Ligação a GTP rhoC/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Fatores Quimiotáticos/farmacologia , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/metabolismo , Interleucina-10/análise , Interleucina-10/metabolismo , Interleucina-10/farmacologia , Interleucina-6/análise , Interleucina-6/metabolismo , Interleucina-6/farmacologia , Interleucina-8/análise , Interleucina-8/metabolismo , Interleucina-8/farmacologia , Macrófagos/citologia , Microfluídica , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
5.
J Biol Chem ; 291(26): 13715-29, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27129239

RESUMO

Inflammatory breast cancer (IBC) is an extremely lethal cancer that rapidly metastasizes. Although the molecular attributes of IBC have been described, little is known about the underlying metabolic features of the disease. Using a variety of metabolic assays, including (13)C tracer experiments, we found that SUM149 cells, the primary in vitro model of IBC, exhibit metabolic abnormalities that distinguish them from other breast cancer cells, including elevated levels of N-acetylaspartate, a metabolite primarily associated with neuronal disorders and gliomas. Here we provide the first evidence of N-acetylaspartate in breast cancer. We also report that the oncogene RhoC, a driver of metastatic potential, modulates glutamine and N-acetylaspartate metabolism in IBC cells in vitro, revealing a novel role for RhoC as a regulator of tumor cell metabolism that extends beyond its well known role in cytoskeletal rearrangement.


Assuntos
Ácido Aspártico/análogos & derivados , Glutamina/metabolismo , Neoplasias Inflamatórias Mamárias/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Ácido Aspártico/biossíntese , Ácido Aspártico/genética , Linhagem Celular Tumoral , Feminino , Glutamina/genética , Humanos , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/patologia , Proteínas de Neoplasias/genética , Proteínas rho de Ligação ao GTP/genética , Proteína de Ligação a GTP rhoC
6.
J Indian Soc Periodontol ; 16(4): 492-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23493978

RESUMO

OBJECTIVE: To investigate the effects of hyperbaric oxygen (HBO2) on aggressive periodontitis (AgP), and subgingival obligate anaerobes in Chinese patients. MATERIALS AND METHODS: Sixty cases of Chinese patients with AgP were randomly divided into two groups -the HBO2 group (30 cases) and the control group (30 cases). Study teeth were divided into four groups -: the HBO2 therapy, the HBO2 + scaling scaling group, the scaling group and the control group. Subgingival anaerobic organisms were measured with anaerobic culture, and number of obligate anaerobes and facultative anaerobes and Bacteroides melaninogenicus was counted. Comparisons of changes in the clinical indices, and subgingival anaerobes were made between the groups. RESULTS: Highly significant differences in gingival index (GI), probing depth (PD), attachment loss (AL), and Plaque index (PLI), and tooth odontoseisis (TO) were seen in the HBO2, the HBO2 + scaling and the scaling groups when compared with the control group (P<0.01). The number of subgingival anaerobes as well as the types of obligate anaerobes and facultative anaerobes and the number of Bacteroides melaninogenicus were reduced markedly in these three treatment groups. Highly statistical differences in clinical indices, subgingival anaerobe number and types of obligate anaerobes and facultative anaerobes and Bacteroides melaninogenicus were found when comparisons were made between the HBO2 + scaling and the HBO2 groups, as well as between the HBO2 + scaling and the scaling groups. Clinical follow-ups indicated that the GI, PD, AL, TO, PLI and subgingival anaerobes number of the three therapeutic groups were reduced more severely than the control group. CONCLUSIONS: HBO2 had good therapeutic effects on Chinese patients with AgP. HBO2 therapy combined with scaling and root planing was the most beneficial in the treatment of AgP. The therapeutic effect of HBO2 on AgP is most likely through inhibition of the growth of subgingival anaerobes. Clinical follow-ups suggest that the effect could last more than 2 years.

7.
Biomaterials ; 31(31): 7892-927, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20684986

RESUMO

Periodontitis is a globally prevalent inflammatory disease that causes the destruction of the tooth-supporting apparatus and potentially leads to tooth loss. Currently, the methods to reconstitute lost periodontal structures (i.e. alveolar bone, periodontal ligament, and root cementum) have relied on conventional mechanical, anti-infective modalities followed by a range of regenerative procedures such as guided tissue regeneration, the use of bone replacement grafts and exogenous growth factors (GFs), and recently developed tissue engineering technologies. However, all current or emerging paradigms have either been shown to have limited and variable outcomes or have yet to be developed for clinical use. To accelerate clinical translation, there is an ongoing need to develop therapeutics based on endogenous regenerative technology (ERT), which can stimulate latent self-repair mechanisms in patients and harness the host's innate capacity for regeneration. ERT in periodontics applies the patient's own regenerative 'tools', i.e. patient-derived GFs and fibrin scaffolds, sometimes in association with commercialized products (e.g. Emdogain and Bio-Oss), to create a material niche in an injured site where the progenitor/stem cells from neighboring tissues can be recruited for in situ periodontal regeneration. The choice of materials and the design of implantable devices influence therapeutic potential and the number and invasiveness of the associated clinical procedures. The interplay and optimization of each niche component involved in ERT are particularly important to comprehend how to make the desired cell response safe and effective for therapeutics. In this review, the emerging opportunities and challenges of ERT that avoid the ex vivo culture of autologous cells are addressed in the context of new approaches for engineering or regeneration of functional periodontal tissues by exploiting the use of platelet-rich products and its associated formulations as key endogenous resources for future clinical management of periodontal tissue defects.


Assuntos
Regeneração Tecidual Guiada Periodontal/métodos , Periodonto/fisiologia , Medicina Regenerativa/métodos , Animais , Materiais Biocompatíveis/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Periodonto/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
8.
Biomaterials ; 31(24): 6279-308, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20493521

RESUMO

Inspired by physiological events that accompany the "wound healing cascade", the concept of developing a tissue either in vitro or in vivo has led to the integration of a wide variety of growth factors (GFs) in tissue engineering strategies in an effort to mimic the natural microenvironments of tissue formation and repair. Localised delivery of exogenous GFs is believed to be therapeutically effective for replication of cellular components involved in tissue development and the healing process, thus making them important factors for tissue regeneration. However, any treatment aiming to mimic the critical aspects of the natural biological process should not be limited to the provision of a single GF, but rather should release multiple therapeutic agents at an optimised ratio, each at a physiological dose, in a specific spatiotemporal pattern. Despite several obstacles, delivery of more than one GF at rates mimicking an in vivo situation has promising potential for the clinical management of severely diseased tissues. This article summarises the concept of and early approaches toward the delivery of dual or multiple GFs, as well as current efforts to develop sophisticated delivery platforms for this ambitious purpose, with an emphasis on the application of biomaterials-based deployment technologies that allow for controlled spatial presentation and release kinetics of key biological cues. Additionally, the use of platelet-rich plasma or gene therapy is addressed as alternative, easy, cost-effective and controllable strategies for the release of high concentrations of multiple endogenous GFs, followed by an update of the current progress and future directions of research utilising release technologies in tissue engineering and regenerative medicine.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Engenharia Tecidual/métodos , Animais , Técnicas de Transferência de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Plasma Rico em Plaquetas
9.
Cancer ; 116(11 Suppl): 2768-82, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20503409

RESUMO

BACKGROUND: The 2 closely related small GTPases, RHOC and RHOA, are involved in mammary gland carcinogenesis; however, their specific roles in determining cancer cell adhesion and invasion have not been elucidated. METHODS: RHOA and RHOC are highly homologous, thereby posing a major challenge to study their individual functions in cancer cells. By selectively knocking down these proteins, we have been able to alternatively inhibit RHOC and RHOA, while preserving expression of the other rho protein. Quantitative analyses of the growth patterns and invasion in the aggressive estrogen receptor negative cell lines MDA-231 and SUM149 were carried out on collagen I and Matrigel substrates. RESULTS: RHOC, and not RHOA, modulates surface expression and colocalization of alpha2 and beta1 integrins in MDA-MB-231 on collagen I. Neither RHOC or RHOA affected integrin expression in the inflammatory breast cancer cell line SUM149, further highlighting the different regulation of adhesion and motility in inflammatory breast cancer. CONCLUSIONS: This work shows that RHOC and RHOA play different roles in cell-matrix adhesion, motility, and invasion of MDA-MB-231 and reaffirms the crucial role of RHOC-GTPase in inflammatory breast cancer cell invasion.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Proteínas rho de Ligação ao GTP/fisiologia , Proteína rhoA de Ligação ao GTP/fisiologia , Movimento Celular , Células Clonais , Feminino , Técnicas de Silenciamento de Genes , Humanos , Inflamação/enzimologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Invasividade Neoplásica , RNA Interferente Pequeno/farmacologia , Proteína de Ligação a GTP rhoC
10.
Integr Cancer Ther ; 8(3): 242-53, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19815594

RESUMO

PURPOSE: Pomegranate fruit extracts (PFEs) possess polyphenolic and other compounds with antiproliferative, pro-apoptotic and anti-inflammatory effects in prostate, lung, and other cancers. Because nuclear transcription factor-kB (NF-kB) is known to regulate cell survival, proliferation, tumorigenesis, and inflammation, it was postulated that PFEs may exert anticancer effects at least in part by modulating NF-kB activity. EXPERIMENTAL DESIGN: The authors investigated the effect of a novel, defined PFE consisting of both fermented juice and seed oil on the NF-kB pathway, which is constitutively active in aggressive breast cancer cell lines. The effects of the PFE on NF-kB-regulated cellular processes such as cell survival, proliferation, and invasion were also examined. RESULTS: Analytical characterization of the bioactive components of the PFE revealed active constituents, mainly ellagitannins and phenolic acids in the aqueous PFE and conjugated octadecatrienoic acids in the lipid PFE derived from seeds.The aqueous PFE dose-dependently inhibited NF-kB-dependent reporter gene expression associated with proliferation, invasion, and motility in aggressive breast cancer phenotypes while decreasing RhoC and RhoA protein expression. CONCLUSION: Inhibition of motility and invasion by PFEs, coincident with suppressed RhoC and RhoA protein expression, suggests a role for these defined extracts in lowering the metastatic potential of aggressive breast cancer species.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Frutas/química , Lythraceae/química , Extratos Vegetais/farmacologia , Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dinoprostona/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Leucotrieno B4/metabolismo , NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Invasividade Neoplásica/patologia , Fitoterapia , Fator de Transcrição RelA/metabolismo , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína de Ligação a GTP rhoC
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 27(3): 264-7, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19637473

RESUMO

OBJECTIVE: To study the influence of transfection with human transforming growth factor-beta1 (hTGF-beta1) gene on the osteogenic potential and differentiation of the cultured human gingival fibroblast (GF). METHODS: Enzyme kinetics method was used to measure the effects of the transfection on the alkaline phosphatase (ALP) activity. Immunohistochemistry stain and image analysis were applied to evaluate the alteration of the content of osteopontin (OPN), bone sialoprotein (BSP), osteonectin (ON), osteocalcin (OC) in the GF with transfection. Mineralization nodules formation in vitro was also used. RESULTS: The ALP activity of the GF after transfection was higher than the GF without transfection significantly (P<0.05), and was close to that of the PDLCs (P>0.05). The content of OC in GF was not improved after transfection, was similar with that of PDLCs (P>0.05). Under immunohistochemistry stain, the contents of OPN, ON, BSP expressed in GF with transfection were higher than those of GF without transfection (P<0.05), but similar to those of PDLCs (P>0.05). In the mineralized cultured medium, the nodules were observed in the GF with transfection and PDLCs after 21 days and 24 days alternatively. After von Kossa stain, purple mineralization nodules were observed. CONCLUSION: The GF transfected with pcDNA3-hTGF-beta1 could express some osteogenic characters, though these characters are restricted.


Assuntos
Fosfatase Alcalina , Osteocalcina , Diferenciação Celular , Fibroblastos , Gengiva , Humanos , Sialoproteína de Ligação à Integrina , Osteonectina , Osteopontina , Transfecção , Fator de Crescimento Transformador beta1
12.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 44(5): 274-8, 2009 May.
Artigo em Chinês | MEDLINE | ID: mdl-19575983

RESUMO

OBJECTIVE: To evaluate the effects of gingival fibroblasts (GF) transfected with hTGF-beta1 gene on improving the periodontal tissue regeneration for the repair of degree II artificial furcation defects. METHODS: The gingival fibroblasts transfected with hTGF-beta1 gene was compounded to the cuttlebone-transformed nanometer hydroxyapatite (CBHA) material from the cuttlefish in vitro, the degree II furcation defects on the premolars of dogs were produced surgically, and the compound was to implanted into the defect (transfected group), and compared with the compound of periodontal ligament cells (PDLC) with nanometer HA material and the compound of untransfected GF with HA. The results were examined histologically 8 weeks after operation. RESULTS: In the transfected group and the positive control group, more new attachment was found compared with the negative control (P < 0.01), and the NC, NB and NC of the transfected group and the positive control group were: (2.97 +/- 0.50), (4.29 +/- 0.26) and (4.73 +/- 0.06) mm; (3.09 +/- 0.26), (4.46 +/- 0.25) and (4.69 +/- 0.10) mm, respectively. There was no significant difference between the two groups (P > 0.05). Although the alveolar bone regeneration was found in the untransfected group [NB = (3.46 +/- 0.32) mm], the root resorption was observed. The tracing experiment showed that the transfected GF were found in the new alveolar bone and the periodontal membrane. CONCLUSIONS: GF transfected with hTGF-beta1 gene can significantly improve the periodontal tissue regeneration in treatment of degree II furcation defects and is involved in the formation of the new alveolar bone and the new periodontal membrane.


Assuntos
Gengiva , Regeneração Tecidual Guiada Periodontal , Ligamento Periodontal , Transfecção , Fator de Crescimento Transformador beta/genética , Animais , Cães , Fibroblastos , Gengiva/citologia , Masculino , Nanoestruturas , Engenharia Tecidual
13.
Biomaterials ; 30(28): 5215-24, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19560814

RESUMO

Growth factors play an important role in the complex cascade of tissue events in periodontal regeneration, although optimal methods of delivery remain to be identified. We hypothesize that multiple delivery of growth factors, particularly via a microparticle-containing scaffold, will enhance cellular events leading to periodontal regeneration. In this study, cellular responses of periodontal ligament fibroblasts (PDLFs) in scaffolds containing microparticles (MPs) loaded with either bone morphogenetic protein (BMP)-2, insulin-like growth factor (IGF)-1, or a mixture of both MPs were evaluated, and the dual-MP-containing scaffold exhibited the release of different proteins in a sustained and independent fashion. When PDLF-seeded scaffolds were cultured in a flow perfusion bioreactor, cell metabolism and proliferation of PDLFs were significantly increased within 3 days in all IGF-1-containing scaffolds compared with those in groups lacking IGF-1 and particulate delivery enhanced these effects between 3 and 7 days. The dual-MP-containing group showed the most positive results. Both the BMP-2-in-MP and IGF-1-in-MP groups showed greater effects of alkaline phosphatase activity, more osteocalcin and osteopontin production, and more calcium deposition compared with matched GF-adsorbed groups. All osteoblastic markers were at their highest in the dual-MP-containing group at all detected time points. The combined results suggest that our dual-MP-containing scaffold can be used as a cell vehicle to positively affect cell behavior, thus exhibiting the potential to be a candidate scaffold for future periodontal tissue engineering.


Assuntos
Proteína Morfogenética Óssea 2/administração & dosagem , Preparações de Ação Retardada/química , Fibroblastos/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/administração & dosagem , Ligamento Periodontal/citologia , Alicerces Teciduais/química , Adolescente , Proteína Morfogenética Óssea 2/farmacologia , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Criança , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Osteogênese/efeitos dos fármacos
14.
Curr Gene Ther ; 9(4): 248-66, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19534653

RESUMO

The cellular and molecular events of periodontal healing are coordinated and regulated by an elaborate system of signaling molecules, pointing to a primary strategy for functional periodontal compartment regeneration to replicate components of the natural cellular microenvironment by providing an artificial extracellular matrix (ECM) and by delivering growth factors. However, even with optimal carriers, the localized delivery of growth factors often requires a large amount of protein to stimulate significant effects in vivo, which increases the risk and unwanted side effects. A simple and relatively new approach to bypassing this dilemma involves converting cells into protein producing factories. This is done by a so-called gene delivery method, where therapeutic agents to be delivered are DNA plasmids that include the gene encoding desired growth factors instead of recombinant proteins. As localized depots of genes, novel gene delivery systems have the potential to release their cargo in a sustained and controlled manner and finally provide time- and space- dependent levels of encoded proteins during all stages of tissue regrowth, offering great versatility in their application and prompting new tissue engineering strategy in periodontal regenerative medicine. However, gene therapy in Periodontology is clearly in its infancy. Significant efforts still need to be made in developing safe and effective delivery platforms and clarifying how gene delivery, in combination with tissue engineering, may mimic the critical aspects of natural biological processes occurring in periodontal development and repair. The aim of this review is to trace an outline of the state-of-the-art in the application of gene delivery and tissue engineering strategies for periodontal healing and regeneration.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Doenças Periodontais/terapia , Periodonto/fisiologia , Regeneração/genética , Engenharia Tecidual , Matriz Extracelular/genética , Vetores Genéticos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Periodonto/citologia , Plasmídeos , Cicatrização/genética
15.
Acta Pharmacol Sin ; 30(4): 485-93, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19305420

RESUMO

AIM: Localized delivery of growth factors has significant potential as a future therapeutic strategy in tissue engineering and regenerative medicine. A nanoparticle vehicle was created and evaluated in this study with the intent to deliver growth factors for periodontal regeneration. METHODS: Novel composite nanoparticles based on glycidyl methacrylate derivatized dextrans (Dex-GMA) and gelatin were fabricated by a facile method without using any organic solvents. The configurations of the resultant nanoparticles were evaluated by transmission electron microscopy, scanning electron microscopy, and atomic force microscope. Their surfaces were characterized by zeta-potential measurements, after which their properties including swelling, degradation, drug release, and cytotoxicity were also investigated using in vitro models. RESULTS: The particle size of Dex-GMA/gelatin nanoparticles (DG-NPs) ranged from 20 to 100 nm and showed a mono-disperse size distribution (mean diameter 53.7 nm) and a strongly negative surface zeta potential (-20 mV). The DG-NPs were characterized by good swelling and degradation properties in media including dextranase. The in vitro drug release studies showed that the efficient bone morphogenetic protein (BMP) release from DG-NPs was maintained for more than 12 d under degradation conditions, where more than 90% of the loaded BMP was released. No any relevant cell damage caused by DG-NPs was found in the cytotoxicity tests for a period of 24 h. CONCLUSION: These combined results demonstrate that DG-NPs fulfill the basic prerequisites for growth factor delivery. With further in vivo studies, those nanoparticles may offer a promising vehicle for the delivery of active drugs to the periodontium.


Assuntos
Proteínas Morfogenéticas Ósseas/administração & dosagem , Dextranos/administração & dosagem , Sistemas de Liberação de Medicamentos , Compostos de Epóxi/administração & dosagem , Gelatina/administração & dosagem , Metacrilatos/administração & dosagem , Nanopartículas/administração & dosagem , Adolescente , Proteínas Morfogenéticas Ósseas/química , Proteínas Morfogenéticas Ósseas/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dextranos/química , Compostos de Epóxi/química , Gelatina/química , Humanos , Metacrilatos/química , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Periodonto/metabolismo , Regeneração
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(5): 273-7, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18953910

RESUMO

OBJECTIVE: To observe the effect of the self-made chitosan thermosensitive hydrogel system with dual-release bone morphogenetic protein and chlorhexidine on periodontal defects repair. METHODS: The furcation defect model was established on dog premolar. The models were divided into five groups, including three experimental groups, one control group and one blank control group. The hydrogel with the chlorhexidine/3-cyclodextrin inclusion complexes (IC) /rhBMP-2, hydrogel with rhBMP-2, hydrogel with IC, the pure hydrogel were applied to the defects of the four groups, respectively, and the blank control group did not receive any agent. The dogs were sacrificed 8 weeks later and the periodontal regeneration and gingival condition were observed by histological examination. RESULTS: Obvious periodontal tissue regeneration was found in group one and two. The heights of new bone reached 99.2% of the defects in group one, 87.8%, 63.6%, 37.0% and 34.3% in group two, three, four and blank control groups, respectively. The inflammation of the affected gingiva showed less significant in group one and group three than in the other groups. CONCLUSIONS: rhBMP-2 and chlorhexidine played their independent role in repairing periodontal defects and the dual-release chitosan thermosensitive hydrogel system is effective and convenient to use.


Assuntos
Quitosana/farmacologia , Hidrogéis/farmacologia , Periodonto/efeitos dos fármacos , Periodonto/fisiologia , Animais , Proteínas Morfogenéticas Ósseas/farmacologia , Clorexidina/farmacologia , Cães , Masculino , Regeneração , Engenharia Tecidual
17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 26(1): 23-6, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18357877

RESUMO

OBJECTIVE: To observe the effect of the chitosan thermosensitive hydrogel loading recombinant human bone morphogenetic protein-2 (rhBMP-2) on repairing periodontal defects. METHODS: To prepare artificial furcation defects model in the posterior area in 3 healthy male dogs, and then to inject chitosan thermosensitive hydrogel loading of rhBMP-2 after fast suturing tissue flap. The groups filled with nothing or filled only with chitosan thermosensitive hydrogel were the controls. The dogs were sacrificed after 5 weeks and the periodontal regeneration was observed histologically. RESULTS: The histological observation showed that the chitosan thermosensitive hydrogel loading rhBMP-2 group achieved apparent periodontal tissue regeneration occupying the majority of the defects and the control groups got only a small amount of periodontal tissue regeneration. CONCLUSION: The chitosan thermosensitive hydrogel loading rhBMP-2 can effectively promote the periodontal tissue regeneration, while simplifying the surgical operation. It might be a potential means for periodontal regeneration.


Assuntos
Quitosana , Hidrogel de Polietilenoglicol-Dimetacrilato , Animais , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas , Cães , Humanos , Masculino , Proteínas Recombinantes , Regeneração , Fator de Crescimento Transformador beta
19.
J Clin Periodontol ; 34(11): 946-51, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17877744

RESUMO

OBJECTIVE: The aim of this work was to estimate the present periodontal problems of people in China, based on an epidemiological investigation of adults. MATERIAL AND METHODS: The data were collected from the northwest, southwest, northeast and east regions (400 subjects from each region) of China. All subjects were over 25 years of age. About half of the subjects were farmers and about half were urban professionals. Everyone was asked to fill out a questionnaire and to undergo a professional oral examination. Periodontal health status was evaluated by a simplified oral hygiene index (OHI-S), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PD), clinical attachment loss (CAL), and tooth mobility. RESULTS: Of the 1590 subjects enrolled in this investigation, 45.7% were male, 45.5% were farmers, and the remaining were urban professionals, and 27.7% of the subjects were smokers. There was a significant difference in the educational background but not smoking between the rural and urban groups. While 34.9% of the subjects in the urban group brushed only once per day, 56.1% of the subjects in the rural group did so. The prevalence of bleeding during brushing was 71.1%, while about 61.4% of the subjects know nothing about scaling. All periodontal indices were significantly higher in males than in females and higher in the rural group than in the urban group. PD, CAL and tooth mobility increased with age. The percentage of sites with CAL>3 mm in the rural group (49.5%) was significantly higher than that in the urban group (37.5%). Both current and former smokers showed increased CAL than non-smokers. CONCLUSION: Gingivitis and periodontitis are common findings in China. Most Chinese have no knowledge of common periodontal prevention and treatment and very few have regular dental care. The data of this study suggest that age, smoking, and limited education are significantly associated with Chinese adult periodontal attachment loss. Preventive periodontal care and education should be reinforced in the future by establishing relevant oral health projects.


Assuntos
Doenças Periodontais/epidemiologia , Adulto , China/epidemiologia , Escolaridade , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perda da Inserção Periodontal/epidemiologia , Doenças Periodontais/etiologia , Doenças Periodontais/prevenção & controle , População Rural/estatística & dados numéricos , Fumar/efeitos adversos , Fumar/epidemiologia , Fatores Socioeconômicos , Escovação Dentária/estatística & dados numéricos , População Urbana/estatística & dados numéricos
20.
J Control Release ; 121(1-2): 81-90, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17617489

RESUMO

The objective of this study was to evaluate the biological activity enhancement of a novel glycidyl methacrylated dextran (Dex-GMA)/gelatin hybrid hydrogel containing microspheres loaded with bone morphogenetic proteins (BMP) as periodontal cell/tissue scaffold. Larger number of human periodontal ligament cells (PDLCs) attached was observed in scaffolds containing microspheres loaded with BMP when compared to those without microspheres. When osteogenic differentiation of PDLCs in such scaffolds was evaluated, the alkaline phosphatase (ALP) activity, osteocalcin content, and calcium deposition became maximum for the scaffold containing microspheres loaded with BMP, as compared with those without microspheres but adsorbed with the same amount of BMP aqueous solution, although both values were significantly higher than those in BMP-free scaffold. In addition, the osteoinduction activity was also studied following the implantation of these scaffolds into the periodontal defects of dogs in terms of histological examinations, significantly more new bone formation and periodontal ligaments regeneration were observed throughout scaffold containing microspheres. We conclude that the attachment, proliferation, and osteogenic differentiation of PDLCs can be enhanced by Dex-GMA/gelatin hydrogel scaffold containing microspheres loaded with BMP, and such scaffold is promising to enhance periodontal tissue regeneration in periodontal therapy.


Assuntos
Proteínas Morfogenéticas Ósseas/química , Dextranos/química , Compostos de Epóxi/química , Gelatina/química , Metacrilatos/química , Ligamento Periodontal/crescimento & desenvolvimento , Adsorção , Fosfatase Alcalina/análise , Fosfatase Alcalina/metabolismo , Materiais Biocompatíveis/química , Proteína Morfogenética Óssea 2 , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/farmacologia , Regeneração Óssea/efeitos dos fármacos , Cálcio/metabolismo , Adesão Celular , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dextranos/ultraestrutura , Gelatina/ultraestrutura , Humanos , Microesferas , Osteocalcina/análise , Ligamento Periodontal/citologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/fisiologia , Polietilenoglicóis/química , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Fator de Crescimento Transformador beta , Água/química
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