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1.
Front Plant Sci ; 13: 830140, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498646

RESUMO

Glucose can serve as both the source of energy and regulatory signaling molecule in plant. Due to the environmental and metabolic change, sugar levels could affect various developmental processes. High glucose environment is hardly conductive to the plant growth but cause development arrest. Increasing evidence indicate that alternative splicing (AS) plays a pivotal role in sugar signaling. However, the regulatory mechanism upon glucose stress remains unclear. The full-length transcriptomes were obtained from the samples of Arabidopsis seedlings with 3% glucose and mock treatment, using Oxford Nanopore sequencing technologies. Further analysis indicated that many genes involved in photosynthesis were significantly repressed and many genes involved in glycolysis, mitochondrial function, and the response to oxidative stress were activated. In total, 1,220 significantly differential alternative splicing (DAS) events related to 619 genes were identified, among which 75.74% belong to intron retention (IR). Notably, more than 20% of DAS events come from a large set of glycine-rich protein (GRP) family genes, such as GRP7, whose AS types mostly belong to IR. Besides the known productive GRP transcript isoforms, we identified a lot of splicing variants with diverse introns spliced in messenger RNA (mRNA) region coding the glycine-rich (GR) domain. The AS pattern of GRPs changed and particularly, the productive GRPs increased upon glucose stress. These ASs of GRP pre-mRNAs triggered by glucose stress could be abolished by AZD-8055, which is an ATP competitive inhibitor for the target of rapamycin (TOR) kinase but could be mimicked by H2O2. Additionally, AS pattern change of arginine/serine-rich splicing factor 31(RS31) via TOR pathway, which was previously described in response to light and sucrose signaling, was also induced in a similar manner by both glucose stress and reactive oxygen species (ROS). Here we conclude that (i) glucose stress suppresses photosynthesis and activates the glycolysis-mitochondria energy relay and ROS scavenging system; (ii) glucose stress triggers transcriptome-wide AS pattern changes including a large set of splicing factors, such as GRPs and RS31; (iii) high sugars regulate AS pattern change of both GRPs and RS31 via TOR-ROS pathway. The results from this study will deepen our understanding of the AS regulation mechanism in sugar signaling.

3.
Stem Cells ; 36(2): 180-191, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29119708

RESUMO

Cancer stem cells (CSCs)/cancer-initiating cells (CICs) are suggested responsible for driving cancer resistance to conventional therapies and for cancer recurrence and/or metastasis. CD133 is served as a key biomarker to identify and characterize this subpopulation of cells in hepatocellular carcinoma (HCC). Our previous study indicated that overexpression of eukaryotic initiation factor 5A2 (EIF5A2) promotes HCC cell metastasis and angiogenesis. In this study, we demonstrated that EIF5A2 might play a crucial role in CSCs regulation and investigated its potential molecular mechanisms. Using quantitative real-time polymerase chain reaction assay, we observed that the expression of EIF5A2 positively correlated with CD133 levels in a cohort of cancerous and noncancerous liver tissues and cells. Next, HCC cells with high expression of EIF5A2 have a strong capacity to form undifferentiated tumor spheres in vitro and show elevated levels of stem cell-related genes, leading to an increased ability to develop tumors when subcutaneously injected into nude mice. Furthermore, differential microRNA expression was profiling between two EIF5A2-depleted HCC cell lines and their control one identified a decreased expression of miR-29b in EIF5A2-depleted cell lines. Further functional studies illustrated that downregulated miR-29b level is responsible for EIF5A2-maintained HCC cell stemness either in vitro or in vivo. Moreover, enforced expression of EIF5A2 in HCC cells largely enhanced the binding of c-Myc on the promoter of miR-29b and downregulation of miR-29b by EIF5A2 was dependent on c-Myc. Our findings, collectively, reveal that EIF5A2 contributes to the maintenance of CD133+ HCC cells via the c-Myc/miR-29b axis. Stem Cells 2018;36:180-191.


Assuntos
Antígeno AC133/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas de Ligação a RNA/metabolismo , Antígeno AC133/genética , Animais , Western Blotting , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos SCID , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Fatores de Iniciação de Peptídeos/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ensaios Antitumorais Modelo de Xenoenxerto , Fator de Iniciação de Tradução Eucariótico 5A
4.
Zhongguo Zhong Yao Za Zhi ; 42(9): 1792-1796, 2017 May.
Artigo em Chinês | MEDLINE | ID: mdl-29082709

RESUMO

In this article, medication characteristics of professor Li Dian-gui in treating chronic atrophic gastritis with intestinal metaplasia(CAGIM) were analyzed through traditional Chinese medicine inheritance support system(version 2.5). 276 cases and 625 prescriptions were collected to analyze five types of traditional Chinese medicine(TCM) syndromes and the medicine-syndrome correlation. The results showed that medication characteristics of professor Li Dian-gui in treating CAGIM included drug combination of aromatic medicine bitter-cold herbs, preferring to activating to invigorate the spleen and good at using the qi-regulating drugs. It demonstrated that we can adopt the therapy of Huazhuo Jiedu and Xingpi Xingqi therapies in treating CAGIM in addition to the traditional approach of nourishing Yin and activating blood circulation, opening up a novel approach for TCM in healing the pathema.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Gastrite Atrófica/tratamento farmacológico , Intestinos/patologia , Humanos , Intestinos/efeitos dos fármacos , Medicina Tradicional Chinesa , Metaplasia/tratamento farmacológico , Plantas Medicinais
5.
Medicine (Baltimore) ; 96(36): e7959, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28885348

RESUMO

BACKGROUND: This study aimed to investigate the effect and safety of transcutaneous electrical nerve stimulation (TENS) therapy for relieving pain in women with primary dysmenorrhea (PD). METHODS: In this study, 134 participants with PD were randomly divided into the intervention group and the sham group, with 67 participants in each group. Participants in the intervention group received TENS, whereas those in the sham group received sham TENS. The primary outcome was measured by the Numeric Rating Scale (NRS). The secondary outcomes were measured by the duration of relief from dysmenorrheal pain, number of ibuprofen tablets taken, and the World Health Organization quality of life (WHOQOL)-BREF score, as well as the adverse events. RESULTS: A total of 122 participants completed the study. Compared to sham TENS, TENS showed a greater effect in pain relief with regard to the NRS (P < .01), duration of relief from dysmenorrheal pain (P < .01), and number of ibuprofen tablets taken (P < .01). However, no significant differences in the quality of life, measured by the WHOQOL-BREF score, were found between 2 groups. The adverse event profiles were also similar between 2 groups. CONCLUSION: TENS was efficacious and safe in relieving pain in participants with PD.


Assuntos
Dismenorreia/terapia , Estimulação Elétrica Nervosa Transcutânea , Adulto , Analgésicos não Narcóticos/uso terapêutico , Dismenorreia/psicologia , Feminino , Humanos , Ibuprofeno/uso terapêutico , Manejo da Dor , Medição da Dor , Qualidade de Vida , Método Simples-Cego , Estimulação Elétrica Nervosa Transcutânea/efeitos adversos , Resultado do Tratamento , Adulto Jovem
6.
PLoS One ; 10(2): e0117375, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25714809

RESUMO

Plenty of studies have established that dysregulation of autophagy plays an essential role in cancer progression. The autophagy-related proteins have been reported to be closely associated with human cancer patients' prognosis. We explored the expression dynamics and prognostic value of autophagy-related protein ULK1 by immunochemistry (IHC) method in two independent cohorts of nasopharygeal carcinoma (NPC) cases. The X-tile program was applied to determine the optimal cut-off value in the training cohort. This derived cutoff value was then subjected to analysis the association of ULK1 expression with patients' clinical characteristics and survival outcome in the validation cohort and overall cases. High ULK1 expression was closely associated with aggressive clinical feature of NPC patients. Furthermore, high expression of ULK1 was observed more frequently in therapeutic resistant group than that in therapeutic effective group. Our univariate and multivariate analysis also showed that higher ULK1 expression predicted inferior disease-specific survival (DSS) (P<0.05). Consequently, a new clinicopathologic prognostic model with 3 poor prognostic factors (ie, ULK1 expression, overall clinical stage and therapeutic response) could significantly stratify risk (low, intermediate and high) for DSS in NPC patients (P<0.001). These findings provide evidence that, the examination of ULK1 expression by IHC method, could serve as an effective additional tool for predicting therapeutic response and patients' survival outcome in NPC patients.


Assuntos
Carcinoma/metabolismo , Carcinoma/mortalidade , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/mortalidade , Proteínas Serina-Treonina Quinases/metabolismo , Adulto , Idoso , Área Sob a Curva , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Biomarcadores , Carcinoma/terapia , Terapia Combinada , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/terapia , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Resultado do Tratamento , Regulação para Cima
7.
Oncotarget ; 5(16): 6716-33, 2014 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-25071013

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is a highly vascularized tumor with poor clinical outcome. Our previous work has shown that eukaryotic initiation factor 5A2 (EIF5A2) over-expression enhances HCC cell metastasis. In this study, EIF5A2 was identified to be an independent risk factor for poor disease-specific survival among HCC patients. Both in vitro and in vivo assays indicated that ablation of endogenous EIF5A2 inhibited tumor angiogenesis by reducing matrix metalloproteinase 2 (MMP-2) expression. Given that MMP-2 degrades collagen IV, a main component of the vascular basement membrane (BM), we subsequently investigated the effect of EIF5A2 on tumor vasculature remodeling using complementary approaches, including fluorescent immunostaining, transmission electron microscopy, tumor perfusion assays and tumor hypoxia assays. Taken together, our results indicate that EIF5A2 silencing increases tumor vessel wall continuity, increases blood perfusion and improves tumor oxygenation. Additionally, we found that ablation of EIF5A2 enhanced the chemosensitivity of HCC cells to 5-Fluorouracil (5-FU). Finally, we demonstrated that EIF5A2 might exert these functions by enhancing MMP-2 activity via activation of p38 MAPK and JNK/c-Jun pathways. CONCLUSION: This study highlights an important role of EIF5A2 in HCC tumor vessel remodeling and indicates that EIF5A2 represents a potential therapeutic target in the treatment of HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Metaloproteinase 2 da Matriz/biossíntese , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/terapia , Fatores de Iniciação de Peptídeos/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A
8.
J Biomed Mater Res A ; 94(2): 539-46, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20186773

RESUMO

In this study a three step culture system, 2D-3D sequential culture in vitro and further implantation in vivo was developed to induce human embryonic stem cells (hESCs) into cartilage like tissues. Five-day-old embryoid bodies were plated for chondrogenic induction for 27 days (step1), then the cells were suspended in alginate and seeded onto polylactic-co-glycolic acid (PLGA) scaffolds for 3D cultivation for 7 days (step 2) and the cells/alginate/PLGA complexes were further transplanted into nude mice for 8 weeks (step 3). At same time, some of complexes were cultured in vitro up to 8 weeks. At the end of step 1, cells exhibited fibroblast-like morphology and expressed chondrocyte-specific markers, Sox 9 and collagen II. During the following 8 weeks of 3D cultivation in vitro, cells displayed spherical morphology, decreased immunoreactivity to Sox-9 and increased one to collagen II, demonstrated further differentiation to mature chondrocyte. In implanted grafts, not only cells appeared typical chondrocytes shape and markers but also cartilage like tissues were formed. These results indicate that 2D-3D sequential culture in vitro is an efficient protocol to induce hESCs differentiates into chondrocytes, while the three step culture system may be an appropriate procedure to derive cartilage like tissues from hESCs.


Assuntos
Alginatos/química , Cartilagem/fisiologia , Técnicas de Cultura de Células , Células-Tronco Embrionárias/fisiologia , Ácido Láctico/química , Ácido Poliglicólico/química , Alicerces Teciduais/química , Alginatos/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Cartilagem/citologia , Diferenciação Celular , Linhagem Celular , Condrócitos/citologia , Condrócitos/fisiologia , Células-Tronco Embrionárias/citologia , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Humanos , Implantes Experimentais , Ácido Láctico/metabolismo , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Engenharia Tecidual/métodos
9.
Biomaterials ; 30(9): 1706-14, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19135250

RESUMO

Islet-like cells derived from embryonic stem (ES) cells may be a promising therapeutic option for future diabetes treatment. Here, we demonstrated a five-stage protocol with adding exendin-4 instead of nicotinamide finally could generate islet-like cells from human embryonic stem (ES) cells. Immunofluorescence analysis revealed a high percentage of c-peptide positive cells in the derivation. However, in addition to insulin/c-peptide, most cells also coexpressed PDX-1 (pancreas duodenum homeobox-1), glucagon, somatostatin or pancreatic polypeptide. Insulin and other pancreatic beta-cell-specific genes were all present in the differentiated cells. Insulin secretion could be detected and increased significantly by adding KCL in high glucose concentration in vitro. Furthermore, subcutaneous transplantation of scaffolds seeded with the islet-like cells or cell transplantation under kidney capsules for further differentiation in vivo could improve 6h fasted blood glucose levels and diabetic phenotypes in streptozotocin-induced diabetic SCID mice. More interestingly, blood vessels of host origin, characterized by mouse CD31 immunostaining, invaded the cell-scaffold complexes. This work reveals a five-stage protocol with adding exendin-4 may be an effective protocol on the differentiation of human ES cells into islet-like cells, and suggests scaffolds can serve as vehicles for islet-like cell transplantation.


Assuntos
Diabetes Mellitus Experimental/complicações , Células-Tronco Embrionárias/citologia , Hiperglicemia/complicações , Hiperglicemia/terapia , Ilhotas Pancreáticas/citologia , Ácido Láctico/farmacologia , Ácido Poliglicólico/farmacologia , Alicerces Teciduais , Animais , Biomarcadores , Glicemia/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Jejum/sangue , Comportamento Alimentar/efeitos dos fármacos , Imunofluorescência , Proteínas de Homeodomínio/metabolismo , Humanos , Hiperglicemia/sangue , Insulina/metabolismo , Secreção de Insulina , Proteínas de Filamentos Intermediários/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/ultraestrutura , Transplante das Ilhotas Pancreáticas , Camundongos , Proteínas do Tecido Nervoso/metabolismo , Nestina , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/metabolismo
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