Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Braz J Med Biol Res ; 54(10): e10891, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34287579

RESUMO

Juniperus communis (JCo) is a well-known traditional Chinese medicinal plant that has been used to treat wounds, fever, swelling, and rheumatism. However, the mechanism underlying the anticancer effect of JCo extract on colorectal cancer (CRC) has not yet been elucidated. This study investigated the anticancer effects of JCo extract in vitro and in vivo as well as the precise molecular mechanisms. Cell viability was evaluated using the MTT assay. Cell cycle distribution was examined by flow cytometry analysis, and cell apoptosis was determined by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Protein expression was analyzed using western blotting. The in vivo activity of the JCo extract was evaluated using a xenograft BALB/c mouse model. The tumors and organs were examined through hematoxylin-eosin (HE) staining and immunohistochemistry. The results showed that JCo extract exhibited higher cytotoxicity against CRC cells than against normal cells and showed synergistic effects when combined with 5-fluorouracil. JCo extract induced cell cycle arrest at the G0/G1 phase via regulation of p53/p21 and CDK4/cyclin D1 and induced cell apoptosis via the extrinsic (FasL/Fas/caspase-8) and intrinsic (Bax/Bcl-2/caspase-9) apoptotic pathways. In vivo studies revealed that JCo extract suppressed tumor growth through the inhibition of proliferation and induction of apoptosis. In addition, there was no obvious change in body weight or histological morphology of normal organs after treatment. JCo extract suppressed CRC progression by inducing cell cycle arrest and apoptosis in vitro and in vivo, suggesting the potential application of JCo extract in the treatment of CRC.


Assuntos
Adenocarcinoma , Antineoplásicos Fitogênicos , Neoplasias Colorretais , Juniperus , Adenocarcinoma/tratamento farmacológico , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Ciclo Celular , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/farmacologia
2.
Int J Med Sci ; 18(11): 2417-2430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967620

RESUMO

Glioblastoma (GBM) is the most common malignant primary brain tumor in humans, exhibiting highly infiltrative growth and drug resistance to conventional chemotherapy. Cedrus atlantica (CAt) extract has been shown to decrease postoperative pain and inhibit the growth of K562 leukemia cells. The aim of this study was to assess the anti-GBM activity and molecular mechanism of CAt extract in vitro and in vivo. The results showed that CAt extract greatly suppressed GBM cells both in vitro and in vivo and enhanced the survival rate in subcutaneous and orthotopic animal models. Moreover, CAt extract increased the level of ROS and induced DNA damage, resulting in cell cycle arrest at the G0/G1 phase and cell apoptosis. Western blotting results indicated that CAt extract regulates p53/p21 and CDK4/cyclin D1 protein expression and activates extrinsic and intrinsic apoptosis. Furthermore, CAt extract enhanced the cytotoxicity of Temozolomide and decreased AKT/mTOR signaling by combination treatment. In toxicity assays, CAt extract exhibited low cytotoxicity toward normal cells or organs in vitro and in vivo. CAt extract suppresses the growth of GBM by induction of genotoxicity and activation of apoptosis. The results of this study suggest that CAt extract can be developed as a therapeutic agent or adjuvant for GBM treatment in the future.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Cedrus/química , Glioblastoma/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Camundongos , Extratos Vegetais/uso terapêutico , Ratos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Braz. j. med. biol. res ; 54(10): e10891, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285652

RESUMO

Juniperus communis (JCo) is a well-known traditional Chinese medicinal plant that has been used to treat wounds, fever, swelling, and rheumatism. However, the mechanism underlying the anticancer effect of JCo extract on colorectal cancer (CRC) has not yet been elucidated. This study investigated the anticancer effects of JCo extract in vitro and in vivo as well as the precise molecular mechanisms. Cell viability was evaluated using the MTT assay. Cell cycle distribution was examined by flow cytometry analysis, and cell apoptosis was determined by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Protein expression was analyzed using western blotting. The in vivo activity of the JCo extract was evaluated using a xenograft BALB/c mouse model. The tumors and organs were examined through hematoxylin-eosin (HE) staining and immunohistochemistry. The results showed that JCo extract exhibited higher cytotoxicity against CRC cells than against normal cells and showed synergistic effects when combined with 5-fluorouracil. JCo extract induced cell cycle arrest at the G0/G1 phase via regulation of p53/p21 and CDK4/cyclin D1 and induced cell apoptosis via the extrinsic (FasL/Fas/caspase-8) and intrinsic (Bax/Bcl-2/caspase-9) apoptotic pathways. In vivo studies revealed that JCo extract suppressed tumor growth through the inhibition of proliferation and induction of apoptosis. In addition, there was no obvious change in body weight or histological morphology of normal organs after treatment. JCo extract suppressed CRC progression by inducing cell cycle arrest and apoptosis in vitro and in vivo, suggesting the potential application of JCo extract in the treatment of CRC.


Assuntos
Animais , Coelhos , Neoplasias Colorretais/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Juniperus , Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Ciclo Celular , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Pontos de Checagem do Ciclo Celular , Camundongos Endogâmicos BALB C
4.
Bot Stud ; 61(1): 24, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32940820

RESUMO

BACKGROUND: TCP-domain proteins, plant specific transcription factors, play important roles in various developmental processes. CIN-TCPs control leaf curvature in simple leaf species while regulate leaf complexity in compound leaf species. However, the knowledge was largely based on findings in few model species. To extend our knowledge on this group of proteins in Solanaceae species, we identified a CIN-TCP gene from petunia, and studied its functions using virus-induced gene silencing (VIGS). RESULTS: Consistently, silencing of CIN-TCPs increases complexity of tomato leaves, and enhances leaf curvature in Nicotiana benthamiana. However, in petunia (Petunia hybrida), silencing of petunia LA, a CIN-TCP, through VIGS did not obviously affect leaf shape. The silencing, however, enhanced petal curvature. The event was associated with petal expansion at the distal portion where epidermal cell size along the midribs was also increased. The enlarged epidermal cells became flattened. Although shapes of PhLA-silenced flowers largely resemble phmyb1 mutant phenotype, PhMYB1 expression was not affected when PhLA was specifically silenced. Therefore, both PhLA and PhMYB1 are required to regulate flower morphology. In corolla, PhLA and miR319 deferentially express in different regions with strong expressions in limb and tube region respectively. CONCLUSIONS: In conclusion, unlike LA-like genes in tomato and N. benthamiana, PhLA plays a more defined role in flower morphogenesis, including petal curvature and epidermal cell differentiation.

5.
Front Plant Sci ; 10: 1183, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632422

RESUMO

Phytoplasmas are prokaryotic plant pathogens that cause considerable loss in many economically important crops, and an increasing number of phytoplasma diseases are being reported on new hosts. Knowledge of plant defense mechanisms against such pathogens should help to improve strategies for controlling these diseases. Salicylic acid (SA)-mediated defense may play an important role in defense against phytoplasmas. Here, we report that SA accumulated in Madagascar periwinkle (Catharanthus roseus) infected with periwinkle leaf yellowing (PLY) phytoplasma. CrPR1a expression was induced in both symptomatic and non-symptomatic tissues of plants exhibiting PLY. NPR1 plays a central role in SA signaling, and two NPR1 homologs, CrNPR1 and CrNPR3, were identified from a periwinkle transcriptome database. Similar to CrPR1a, CrNPR1 expression was also induced in both symptomatic and non-symptomatic tissues of plants exhibiting PLY. Silencing of CrNPR1, but not CrNPR3, significantly repressed CrPR1a induction in Tobacco rattle virus-infected periwinkle plants. In addition, symptoms of PLY progressed fastest in CrNPR1-silenced plants and slowest in CrNPR3-silenced plants. Consistently, expression of CrNPR1, but not CrNPR3, was induced by phytoplasma infection as well as SA treatment. This study highlights the importance of NPR1- and SA-mediated defense against phytoplasma in periwinkle and offers insight into plant-phytoplasma interactions to improve disease control strategies.

6.
Lab Chip ; 12(18): 3277-80, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22824954

RESUMO

We have developed an integrated microfluidic material processing chip and demonstrated the rapid production of collagen microspheres encapsulating cells with high uniformity and cell viability. The chip integrated three material processing steps. Monodisperse microdroplets were generated at a microfluidic T junction between aqueous and mineral oil flows. The flow was heated immediately to 37 °C to initiate collagen fiber assembly within a gelation channel. Gelled microspheres were extracted from the mineral oil phase into cell culture media within an extraction chamber. Collagen gelation immediately after microdroplet generation significantly reduced coalescence among microdroplets that led to non-uniform microsphere production. The microfluidic extraction approach led to higher microsphere recovery and cell viability than when a conventional centrifugation extraction approach was employed. These results indicate that chip-based material processing is a promising approach for cell-ECM microenvironment generation for applications such as tissue engineering and stem cell delivery.


Assuntos
Colágeno/química , Técnicas Analíticas Microfluídicas/instrumentação , Linhagem Celular Tumoral , Sobrevivência Celular , Colágeno/metabolismo , Géis/química , Humanos , Microesferas , Óleo Mineral/química
7.
J Biomech ; 45(5): 728-35, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22206828

RESUMO

Cyclic uniaxial stretching of adherent nonmuscle cells induces the gradual reorientation of their actin stress fibers perpendicular to the stretch direction to an extent dependent on stretch frequency. By subjecting cells to various temporal waveforms of cyclic stretch, we revealed that stress fibers are much more sensitive to strain rate than strain frequency. By applying asymmetric waveforms, stress fibers were clearly much more responsive to the rate of lengthening than the rate of shortening during the stretch cycle. These observations were interpreted using a theoretical model of networks of stress fibers with sarcomeric structure. The model predicts that stretch waveforms with fast lengthening rates generate greater average stress fiber tension than that generated by fast shortening. This integrated approach of experiment and theory provides new insight into the mechanisms by which cells respond to matrix stretching to maintain tensional homeostasis.


Assuntos
Mecanotransdução Celular/fisiologia , Modelos Biológicos , Sarcômeros/fisiologia , Fibras de Estresse/fisiologia , Fenômenos Biomecânicos , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Homeostase/fisiologia , Humanos , Osteossarcoma/patologia
8.
PLoS One ; 5(8): e12470, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20814573

RESUMO

BACKGROUND: Cells within tissues are subjected to mechanical forces caused by extracellular matrix deformation. Cells sense and dynamically respond to stretching of the matrix by reorienting their actin stress fibers and by activating intracellular signaling proteins, including focal adhesion kinase (FAK) and the mitogen-activated proteins kinases (MAPKs). Theoretical analyses predict that stress fibers can relax perturbations in tension depending on the rate of matrix strain. Thus, we hypothesized stress fiber organization and MAPK activities are altered to an extent dependent on stretch frequency. PRINCIPAL FINDINGS: Bovine aortic endothelial cells and human osteosarcoma cells expressing GFP-actin were cultured on elastic membranes and subjected to various patterns of stretch. Cyclic stretching resulted in strain rate-dependent increases in stress fiber alignment, cell retraction, and the phosphorylation of the MAPKs JNK, ERK and p38. Transient step changes in strain rate caused proportional transient changes in the levels of JNK and ERK phosphorylations without affecting stress fiber organization. Disrupting stress fiber contractile function with cytochalasin D or Y27632 decreased the levels of JNK and ERK phosphorylation. Previous studies indicate that FAK is required for stretch-induced cell alignment and MAPK activations. However, cyclic uniaxial stretching induced stress fiber alignment and the phosphorylation of JNK, ERK and p38 to comparable levels in FAK-null and FAK-expressing mouse embryonic fibroblasts. CONCLUSIONS: These results indicate that cyclic stretch-induced stress fiber alignment, cell retraction, and MAPK activations occur as a consequence of perturbations in fiber strain. These findings thus shed new light into the roles of stress fiber relaxation and reorganization in maintenance of tensional homeostasis in a dynamic mechanical environment.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fibras de Estresse/metabolismo , Estresse Mecânico , Actinas/metabolismo , Animais , Fenômenos Biomecânicos , Bovinos , Linhagem Celular Tumoral , Forma Celular , Ativação Enzimática , Humanos , Camundongos , Fosforilação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA