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1.
Biosci Rep ; 39(11)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31710082

RESUMO

We performed long non-coding RNA (lncRNA) microarray assay to identify lncRNAs with differential expression between patients with intracranial aneurysm (IA) and healthy control individuals to evaluate their potential use as biomarkers of IA. Arraystar Human lncRNA Microarray v3.0 was performed to identify differentially expressed lncRNAs and mRNAs in plasma samples (4 ml). lncRNAs with the most pronounced differential expression were used to select gene markers, and results were validated by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Plasma levels of TCONS_00000200 (fold change: 2.28) and ENST00000511927 (fold change: 2.50) were significantly higher in IA patients than in healthy individuals (P<0.001), and plasma levels of ENST00000421997 (fold change: 0.45) and ENST00000538202 (fold change: 0.43) were significantly lower in IA patients than in healthy individuals (P<0.001). qRT-PCR confirmed the same trends of up- and down-regulation of these four lncRNAs. A receiver operating characteristic (ROC) curve for TCONS_00000200 showed that the area under the curve (AUC) was 0.963 (95% confidence interval, 0.919-1.000), optimal cut-off point was 0.0081, sensitivity was 90.0%, and specificity was 96.7%. These results indicate that the lncRNA TCONS_00000200 is differentially expressed in the plasma of IA patients and could serve as a biomarker of IA.

2.
Cells ; 8(10)2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31614569

RESUMO

Primary liver cancer is one of the leading causes for cancer-related death worldwide. Transforming growth factor beta (TGF-ß) is a pleiotropic cytokine that signals through membrane receptors and intracellular Smad proteins, which enter the nucleus upon receptor activation and act as transcription factors. TGF-ß inhibits liver tumorigenesis in the early stage by inducing cytostasis and apoptosis, but promotes malignant progression in more advanced stages by enhancing cancer cell survival, EMT, migration, invasion and finally metastasis. Understanding the molecular mechanisms underpinning the multi-faceted roles of TGF-ß in liver cancer has become a persistent pursuit during the last two decades. Contextual regulation fine-tunes the robustness, duration and plasticity of TGF-ß signaling, yielding versatile albeit specific responses. This involves multiple feedback and feed-forward regulatory loops and also the interplay between Smad signaling and non-Smad pathways. This review summarizes the known regulatory mechanisms of TGF-ß signaling in liver cancer, and how they channel, skew and even switch the actions of TGF-ß during cancer progression.

3.
Medicine (Baltimore) ; 98(39): e17130, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574813

RESUMO

Animal studies have demonstrated that autophagy was involved in neuronal damage after intracerebral hemorrhage (ICH). Several studies showed thrombin-antithrombin (TAT) plasma levels were elevated in patients with ICH. In this study, we aimed to evaluate if autophagy occurred in patients with ICH; and the relationship between the severity of brain injury and plasma TAT levels.A novel tissue harvesting device was used during hematoma removal surgery to collect loose fragments of tissue surrounding the affected brain area in 27 ICH patients with hematoma volumes of >30 mL in the basal ganglia. Control tissues were obtained from patients who underwent surgery for arteriovenous malformation (n = 25). Transmission electron microscopy (TEM) and immunohistochemistry for autophagy-related proteins were used to evaluate the ultrastructural and morphologic cellular characteristics; and the extent of autophagy in the recovered tissue specimens. Stroke severity was assessed by using the Glasgow Coma Scale (GCS) and the National Institutes of Health Stroke Scale (NIHSS). An enzyme-linked immunosorbent assay (ELISA) was used to measure plasma TAT levels.Transmission electron microscopy showed autophagosomes and autolysosomes exist in neurons surrounding the hematoma, but not in the control tissues. The number of cells containing autophagic vacuoles correlated with the severity of brain injury. Immunohistochemistry showed strong LC3, beclin 1, and cathepsin D staining in ICH tissue specimens. Plasma TAT levels correlated positively with autophagic cells and ICH severity (P < .01).Autophagy was induced in perihematomal neurons after ICH. Autophagy and plasma TAT levels correlated positively with severity of brain injury. These results suggest that autophagy and increased plasma TAT levels may contribute to the secondary damage in ICH patients.


Assuntos
Autofagia , Hemorragia Cerebral/sangue , Hematoma/sangue , Neurônios/fisiologia , Peptídeo Hidrolases/sangue , Adulto , Idoso , Antitrombina III , Gânglios da Base/metabolismo , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/cirurgia , Feminino , Escala de Coma de Glasgow , Hematoma/fisiopatologia , Hematoma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Cell Mol Med ; 23(2): 740-749, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30479059

RESUMO

CXXC5 is a member of the CXXC-type zinc-finger protein family. Proteins in this family play a pivotal role in epigenetic regulation by binding to unmethylated CpG islands in gene promoters through their characteristic CXXC domain. CXXC5 is a short protein (322 amino acids in length) that does not have any catalytic domain, but is able to bind to DNA and act as a transcription factor and epigenetic factor through protein-protein interactions. Intriguingly, increasing evidence indicates that expression of the CXXC5 gene is controlled by multiple signaling pathways and a variety of transcription factors, positioning CXXC5 as an important signal integrator. In addition, CXXC5 is capable of regulating various signal transduction processes, including the TGF-ß, Wnt and ATM-p53 pathways, thereby acting as a novel and crucial signaling coordinator. CXXC5 plays an important role in embryonic development and adult tissue homeostasis by regulating cell proliferation, differentiation and apoptosis. In keeping with these functions, aberrant expression or altered activity of CXXC5 has been shown to be involved in several human diseases including tumourigenesis. This review summarizes the current understanding of CXXC5 as a transcription factor and signaling regulator and coordinator.

5.
Biochem Mol Biol Educ ; 46(5): 555-560, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30369037

RESUMO

The rapid development and popularization of smart phones and mobile internet has created a new social lifestyle, and correspondingly prompts the transformation of network teaching from desktop computer to mobile teaching. This article has compared the pros and cons of Tsinghua Education Online and WeChat official account (WOA) in fulfilling teaching functions. We also described the construction of WOA platform with the example of WOA-based teaching in biochemistry and molecular biology. The platform can establish nearly 75 menu catalogs and 2,250 items, which is capable for the publication of any types of teaching materials and information. The WOA teaching is well accepted and becomes popular in China due to the free, interactive, attractive, adaptable, portable, sustainable, and more participatory teaching styles. © 2018 International Union of Biochemistry and Molecular Biology, 46(5):555-560, 2018.


Assuntos
Aplicativos Móveis , Software , Ensino
6.
Talanta ; 180: 150-155, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332793

RESUMO

A simple and homogeneous histone assay is developed based on histone-induced DNA compressing coupled with cationic conjugated polymer (CCP)-mediated fluorescence resonance energy transfer (FRET). In this strategy, the CCP serves as the FRET donor and SYBR Green I (SG), which can strongly fluoresce not at its free state but after intercalated into the double stranded calf thymus DNA (dsDNA), serves as the acceptor of FRET. In the absence of histone, the dsDNA-SG and CCP combine with each other through electrostatic interaction and the strong FRET from CCP to SG occurs due to the overlapping between the fluorescent emitting spectrum of the CCP and the absorption spectrum of SG. Upon the introduction of histone, the formed compact complex of histone/dsDNA will lead to the compression of dsDNA structure and prevent SG binding to dsDNA and fluorescing, which gives rise to a significant decrease of FRET efficiency between CCP and SG. Thus, the quantitative analysis of histone is realized by monitoring the change of FRET ratio, namely, the intensity ratio of the two emission bands of CCP and SG. Due to the light harvesting and fluorescence amplification properties of CCP, high sensitivity is achieved with a low detection limit of 0.74ng/mL histone. This strategy provides a simple, homogeneous and sensitive strategy for histone analysis in the study of histone-related biological processes.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Histonas/análise , Polietilenos/química , Animais , Cátions/química , Bovinos , DNA/química , Corantes Fluorescentes/química , Células HeLa , Humanos , Limite de Detecção , Compostos Orgânicos/química , Eletricidade Estática
7.
J Mol Cell Biol ; 10(1): 48-59, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036306

RESUMO

Evading TGF-ß-mediated growth inhibition is often associated with tumorigenesis in liver, including hepatocellular carcinoma (HCC). To better understand the functions and the underlying molecular mechanisms of TGF-ß in HCC initiation and progression, we carried out transcriptome sequencing (RNA-Seq) to identify the target genes of TGF-ß. CXXC5, a member of the CXXC-type zinc finger domain-containing protein family, was identified as a novel TGF-ß target gene in Hep3B HCC cells. Knockdown of CXXC5 attenuated the expression of a substantial portion of TGF-ß target genes and ameliorated TGF-ß-induced growth inhibition or apoptosis of Hep3B cells, suggesting that CXXC5 is required for TGF-ß-mediated inhibition of HCC progression. Analysis of the TCGA database indicated that CXXC5 expression is reduced in the majority of HCC tissue samples in comparison to that in normal tissues. Furthermore, CXXC5 associates with the histone deacetylase HDAC1 and competes its interaction with Smad2/3, thereby abolishing the inhibitory effect of HDAC1 on TGF-ß signaling. These observations together suggest that CXXC5 may act as a tumor suppressor by promoting TGF-ß signaling via a positive feedback loop, and reveal a strategy for HCC to bypass TGF-ß-mediated cytostasis by disrupting the positive feedback regulation. Our findings shed new light on TGF-ß signaling regulation and demonstrate the function of CXXC5 in HCC development.


Assuntos
Apoptose , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/metabolismo , Pontos de Checagem do Ciclo Celular , Neoplasias Hepáticas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Histona Desacetilase 1/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Mapas de Interação de Proteínas , Transdução de Sinais , Proteínas Smad/metabolismo
8.
Acta Biochim Biophys Sin (Shanghai) ; 50(1): 37-50, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228156

RESUMO

Transforming growth factor beta (TGF-ß) is a multi-functional polypeptide that plays a critical role in regulating a broad range of cellular functions and physiological processes. Signaling is initiated when TGF-ß ligands bind to two types of cell membrane receptors with intrinsic Ser/Thr kinase activity and transmitted by the intracellular Smad proteins, which act as transcription factors to regulate gene expression in the nucleus. Although it is relatively simple and straight-forward, this TGF-ß/Smad pathway is regulated by various feedback loops at different levels, including the ligand, the receptor, Smads and transcription, and is thus fine-tuned in terms of signaling robustness, duration, specificity, and plasticity. The precise control gives rise to versatile and context-dependent pathophysiological functions. In this review, we firstly give an overview of TGF-ß signaling, and then discuss how each step of TGF-ß signaling is finely controlled by distinct modes of feedback mechanisms, involving both protein regulators and miRNAs.


Assuntos
Retroalimentação Fisiológica , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Animais , Humanos , Ligantes , Modelos Biológicos , Ligação Proteica , Proteínas Smad/metabolismo
10.
Nat Commun ; 8(1): 2116, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29235476

RESUMO

Metastasis is the main cause of death in cancer patients. TGF-ß is pro-metastatic for malignant cancer cells. Here we report a loss-of-function screen in mice with metastasis as readout and identify OTUD1 as a metastasis-repressing factor. OTUD1-silenced cancer cells show mesenchymal and stem-cell-like characteristics. Further investigation reveals that OTUD1 directly deubiquitinates the TGF-ß pathway inhibitor SMAD7 and prevents its degradation. Moreover, OTUD1 cleaves Lysine 33-linked poly-ubiquitin chains of SMAD7 Lysine 220, which exposes the SMAD7 PY motif, enabling SMURF2 binding and subsequent TßRI turnover at the cell surface. Importantly, OTUD1 is lost in multiple types of human cancers and loss of OTUD1 increases metastasis in intracardial xenograft and orthotopic transplantation models, and correlates with poor prognosis among breast cancer patients. High levels of OTUD1 inhibit cancer stemness and shut off metastasis. Thus, OTUD1 represses breast cancer metastasis by mitigating TGF-ß-induced pro-oncogenic responses via deubiquitination of SMAD7.


Assuntos
Neoplasias da Mama/metabolismo , Proteína Smad7/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Interferência de RNA , Proteína Smad7/genética , Proteases Específicas de Ubiquitina/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Neural Regen Res ; 12(10): 1625-1631, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29171427

RESUMO

Baicalin is a flavonoid compound extracted from Scutellaria baicalensis root. Recent evidence indicates that baicalin is neuroprotective in models of ischemic stroke. Here, we investigate the neuroprotective effect of baicalin in a neonatal rat model of hypoxic-ischemic encephalopathy. Seven-day-old pups underwent left common carotid artery ligation followed by hypoxia (8% oxygen at 37°C) for 2 hours, before being injected with baicalin (120 mg/kg intraperitoneally) and examined 24 hours later. Baicalin effectively reduced cerebral infarct volume and neuronal loss, inhibited apoptosis, and upregulated the expression of p-Akt and glutamate transporter 1. Intracerebroventricular injection of the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) inhibitor LY294002 30 minutes before injury blocked the effect of baicalin on p-Akt and glutamate transporter 1, and weakened the associated neuroprotective effect. Our findings provide the first evidence, to our knowledge that baicalin can protect neonatal rat brains against hypoxic-ischemic injury by upregulating glutamate transporter 1 via the PI3K/Akt signaling pathway.

12.
Exp Ther Med ; 14(1): 91-96, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28672898

RESUMO

The present study aimed to determine the effect of Astragalus polysaccharide (APS) in an in vivo and in vitro rat model of muscle atrophy (cachexia) caused by chronic renal failure (CRF), along with the potential corresponding roles of atroglin-1 and the ubiquitin-proteasome pathway. A rat model of CRF was established using subtotal bilateral nephrectomy. It was observed by reverse transcription-quantitative polymerase chain reaction and western blot analysis that APS and the specific inhibitor of nuclear factor (NF)-κB, pyrrolidine dithiocarbamate (PDTC), significantly reduced the expression of atrogin-1, ubiquitin and the NF-κB subunit p65 mRNA in rat skeletal muscle in vivo and in vitro, respectively (P<0.05). NF-κB and PDTC also markedly reduced the expression of atrogin-1, ubiquitin and p65 protein. In addition, cultured rat myoblasts pretreated with tumor necrosis factor (TNF)-α exhibited significantly reduced expression of atrogin-1, ubiquitin and p65 mRNA in vitro (P<0.05). Fluorescence microscopy was subsequently used to evaluate TNF-α-treated myoblasts administered with APS or PDTC, whereby no evidence of muscle cell atrophy was observed in cells treated with APS. These data suggest that APS may delay muscle cell atrophy associated with cachexia in CRF by targeting atrogin-1 and the ubiquitin-proteasome pathway.

13.
Am J Phys Med Rehabil ; 96(5): 333-340, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27820728

RESUMO

OBJECTIVE: To compare the short-term efficacy of 2 dosages of stretching treatment on the clinical outcomes in infants with congenital muscular torticollis. DESIGN: This was a prospective randomized controlled study. Fifty infants with congenital muscular torticollis who were randomly assigned to 100-times stretching group and 50-times stretching group received stretching treatment for the affected sternocleidomastoid muscle. The outcomes including the head tilt, the cervical passive range of motion, and the muscle function of cervical lateral flexors determined by the muscle function scale were assessed at baseline and at 4 and 8 weeks after treatment. The sternocleidomastoid muscle growth analyzed by the thickness ratio of sternocleidomastoid muscles was measured using ultrasonography at baseline and 8 weeks after treatment. RESULTS: Except the ratio of muscle function scale scores, the postintervention outcomes were all significantly improved in both groups compared with baseline (P < 0.05). The 100-times stretching group showed greater improvement compared with 50-times stretching group in head tilt and cervical passive range of motion at 4 and 8 weeks after treatment (P < 0.05). CONCLUSIONS: Stretching treatment of 2 dosages may effectively improve head tilt, cervical passive range of motion, and sternocleidomastoid muscle growth in infants with congenital muscular torticollis. The stretching treatment of 100 times per day is likely to associate with greater improvement in head tilt and cervical passive range of motion.


Assuntos
Exercícios de Alongamento Muscular/métodos , Torcicolo/congênito , Feminino , Movimentos da Cabeça , Humanos , Lactente , Masculino , Músculos do Pescoço/diagnóstico por imagem , Músculos do Pescoço/crescimento & desenvolvimento , Estudos Prospectivos , Amplitude de Movimento Articular , Torcicolo/reabilitação
14.
J Biol Chem ; 291(24): 12871-9, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27129200

RESUMO

Wnt signaling plays a critical role in embryonic development, tissue homeostasis, and cancer development. Dishevelled (Dvl) is an essential and central component in Wnt signaling, and its stability and activity is tightly regulated. It has been shown that Dvl can be degraded via both the proteasome and autophagy-lysosome pathways. Here we report that receptor for activated C kinase 1 (RACK1) negatively regulates Dishevelled stability and Wnt signaling. RACK1 interacts with Dvl proteins and promotes their lysosomal degradation, and this effect is enhanced by autophagy induction. RACK1 also interacts with LC3 and enhances the association of LC3 with Dvl2, thereby leading to degradation of Dvl proteins through autophagy. These findings reveal a novel regulatory function of RACK1 in Wnt signaling by modulating Dvl stability.


Assuntos
Autofagia , Proteínas Desgrenhadas/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superfície Celular/metabolismo , Via de Sinalização Wnt , Animais , Autofagossomos/metabolismo , Células Cultivadas , Proteínas Desgrenhadas/genética , Proteínas de Ligação ao GTP/genética , Células HEK293 , Humanos , Immunoblotting , Lisossomos/metabolismo , Microscopia Confocal , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/genética , Ligação Proteica , Estabilidade Proteica , Proteólise , Ratos , Receptores de Quinase C Ativada , Receptores de Superfície Celular/genética
15.
Indian J Pediatr ; 83(10): 1195-6, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27094776

RESUMO

Kawasaki disease (KD), also well known as mucocutaneous lymph node syndrome, is an acute febrile disease in children with systemic vasculitis as its main pathological change, and usually occurs in children under the age of 5. KD is now the commonest cause of acquired heart disease in children in Japan, Europe and North America. Although KD is now being increasingly diagnosed in mainland China, there is paucity of data on this condition. To provide clinical basis for the treatment of KD, the authors report their experience on 170 children with KD at Shaanxi People's Hospital, Xi'an, China in this research. This also is one of the largest single centre experiences from China so far.


Assuntos
Cardiopatias , Síndrome de Linfonodos Mucocutâneos , China , Europa (Continente) , Humanos , Vasculite Sistêmica
16.
Zhonghua Yi Xue Za Zhi ; 96(8): 634-9, 2016 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-26932858

RESUMO

OBJECTIVE: To explore the clinical application of automated digital image analysis in leukocyte morphology examination when review criteria of hematology analyzer are triggered. METHODS: The reference range of leukocyte differentiation by automated digital image analysis was established by analyzing 304 healthy blood samples from Peking University First Hospital. Six hundred and ninty-seven blood samples from Peking University First Hospital were randomly collected from November 2013 to April 2014, complete blood cells were counted on hematology analyzer, blood smears were made and stained at the same time. Blood smears were detected by automated digital image analyzer and the results were checked (reclassification) by a staff with abundant morphology experience. The same smear was examined manually by microscope. The results by manual microscopic differentiation were used as"golden standard", and diagnostic efficiency of abnormal specimens by automated digital image analysis was calculated, including sensitivity, specificity and accuracy. The difference of abnormal leukocytes detected by two different methods was analyzed in 30 samples of hematological and infectious diseases. RESULTS: Specificity of identifying abnormalities of white blood cells by automated digital image analysis was more than 90% except monocyte. Sensitivity of neutrophil toxic abnormities (including Döhle body, toxic granulate and vacuolization) was 100%; sensitivity of blast cells, immature granulates and atypical lymphocytes were 91.7%, 60% to 81.5% and 61.5%, respectively. Sensitivity of leukocyte differential count was 91.8% for neutrophils, 88.5% for lymphocytes, 69.1% for monocytes, 78.9% for eosinophils and 36.3 for basophils. The positive rate of recognizing abnormal cells (blast, immature granulocyte and atypical lymphocyte) by manual microscopic method was 46.7%, 53.3% and 10%, respectively. The positive rate of automated digital image analysis was 43.3%, 60% and 10%, respectively. There was no statistic significance between two methods (χ(2) = 0.067, 0.271, 0.000, all P>0.05). Automated digital image analysis could be used to morphology examination with abnormal leukocytes and optimize review criteria of hematology analyzer. CONCLUSION: Sensitivity and specificity of recognizing abnormal blood leukocytes by automated digital image analysis are satisfactory, which can be used as a tool of leukocyte morphology review when review criteria of hematology analyzer are triggered.


Assuntos
Automação Laboratorial , Contagem de Leucócitos , Leucócitos , Diferenciação Celular , Humanos , Microscopia , Valores de Referência , Células-Tronco
17.
J Biol Chem ; 291(1): 382-92, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26555259

RESUMO

TGF-ß is a pleiotropic cytokine that regulates a wide range of cellular actions and pathophysiological processes. TGF-ß signaling is spatiotemporally fine-tuned. As a key negative regulator of TGF-ß signaling, Smad7 exerts its inhibitory effects by blocking receptor activity, inducing receptor degradation or interfering with Smad-DNA binding. However, the functions and the molecular mechanisms underlying the actions of Smad7 in TGF-ß signaling are still not fully understood. In this study we report a novel mechanism whereby Smad7 antagonizes TGF-ß signaling at the Smad level. Smad7 oligomerized with R-Smad proteins upon TGF-ß signaling and directly inhibited R-Smad activity, as assessed by Gal4-luciferase reporter assays. Mechanistically, Smad7 competes with Smad4 to associate with R-Smads and recruits the E3 ubiquitin ligase NEDD4L to activated R-Smads, leading to their polyubiquitination and proteasomal degradation. Similar to the R-Smad-Smad4 oligomerization, the interaction between R-Smads and Smad7 is mediated by their mad homology 2 (MH2) domains. A positive-charged basic region including the L3/ß8 loop-strand module and adjacent amino acids in the MH2 domain of Smad7 is essential for the interaction. These results shed new light on the regulation of TGF-ß signaling by Smad7.


Assuntos
Transdução de Sinais , Proteínas Smad Reguladas por Receptor/metabolismo , Proteína Smad7/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Aminoácidos/metabolismo , Animais , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Células HEK293 , Humanos , Vison , Ubiquitina-Proteína Ligases Nedd4 , Poliubiquitina/metabolismo , Ligação Proteica/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas , Proteólise , Proteína Smad3/química , Proteína Smad3/metabolismo , Proteína Smad4/metabolismo , Proteína Smad7/química , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
18.
Methods Mol Biol ; 1344: 49-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26520117

RESUMO

TGF-ß is a prototype of the TGF-ß cytokine superfamily and exerts multiple regulatory effects on cell activities. It signals through two types of membrane-bound serine/threonine kinase receptors. Upon TGF-ß binding, the type II receptor TßRII recruits the type I receptor TßRI and form a functional heterocomplex. TßRII trans-phosphorylates the GS region of TßRI, thus triggering its kinase activity. Activated TßRI proceeds to activate downstream Smad2/3. Signal intensity and duration through the availability, activity and destiny of TGF-ß receptors are finely controlled by multiple posttranslational modifications such as phosphorylation, ubiquitination, and neddylation. This chapter introduces methods for examination of these modifications of TGF-ß receptors.


Assuntos
Processamento de Proteína Pós-Traducional , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Animais , Linhagem Celular , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética , Ubiquitinação
19.
PLoS One ; 10(10): e0138608, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26452230

RESUMO

OBJECTIVE: To investigate changes of muscle recruitment and coordination following constraint-induced movement therapy, constraint-induced movement therapy plus electrical stimulation, and traditional occupational therapy in treating hand dysfunction. METHODS: In a randomized, single-blind, controlled trial, children with hemiplegic cerebral palsy were randomly assigned to receive constraint-induced movement therapy (n = 22), constraint-induced movement therapy plus electrical stimulation (n = 23), or traditional occupational therapy (n = 23). Three groups received a 2-week hospital-based intervention and a 6-month home-based exercise program following hospital-based intervention. Constraint-induced movement therapy involved intensive functional training of the involved hand during which the uninvolved hand was constrained. Electrical stimulation was applied on wrist extensors of the involved hand. Traditional occupational therapy involved functional unimanual and bimanual training. All children underwent clinical assessments and surface electromyography (EMG) at baseline, 2 weeks, 3 and 6 months after treatment. Surface myoelectric signals were integrated EMG, root mean square and cocontraction ratio. Clinical measures were grip strength and upper extremity functional test. RESULTS: Constraint-induced movement therapy plus electrical stimulation group showed both a greater rate of improvement in integrated EMG of the involved wrist extensors and cocontraction ratio compared to the other two groups at 3 and 6 months, as well as improving in root mean square of the involved wrist extensors than traditional occupational therapy group (p<0.05). Positive correlations were found between both upper extremity functional test scores and integrated EMG of the involved wrist as well as grip strength and integrated EMG of the involved wrist extensors (p<0.05). CONCLUSIONS: Constraint-induced movement therapy plus electrical stimulation is likely to produce the best outcome in improving muscle recruitment and coordination in children with hemiplegic cerebral palsy compared to constraint-induced movement therapy alone or traditional occupational therapy. TRIAL REGISTRATION: chictr.org ChiCTR-TRC-13004041.


Assuntos
Paralisia Cerebral/terapia , Estimulação Elétrica , Hemiplegia/terapia , Modalidades de Fisioterapia/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Paralisia Cerebral/patologia , Criança , Pré-Escolar , Eletromiografia , Humanos , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Extremidade Superior/patologia , Adulto Jovem
20.
Neurochem Int ; 90: 28-35, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26163046

RESUMO

Large-conductance Ca(2+)-activated K(+) channels (BK channels) are widely expressed throughout the vertebrate nervous system, and are involved in the regulation of neurotransmitter release and neuronal excitability. Here, the neuroprotective effects of NS11021, a selective and chemically unrelated BK channel activator, and potential molecular mechanism involved have been studied in rat cortical neurons exposed to glutamate in vitro. Pretreatment with NS11021 significantly inhibited the loss of neuronal viability, LDH release and neuronal apoptosis in a dose-dependent manner. All these protective effects were fully antagonized by the BK-channel inhibitor paxilline. NS11021-induced neuroprotection was associated with reduced oxidative stress, as evidenced by decreased reactive oxygen species (ROS) generation, lipid peroxidation and preserved activity of antioxidant enzymes. Moreover, NS11021 significantly attenuated the glutamate-induced endoplasmic reticulum (ER) calcium release and activation of ER stress markers, including glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and caspase-12. Pretreatment with NS11021 also mitigated the mitochondrial membrane potential (MMP) collapse, cytochrome c release, and preserved mitochondrial Ca(2+) buffering capacity and ATP synthesis after glutamate exposure. Taken together, these results suggest that activation of BK channels via NS11021 protects cortical neurons against glutamate-induced excitatory damage, which may be dependent on the inhibition of ER stress and preservation of mitochondrial dysfunction.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Canais de Potássio Cálcio-Ativados/metabolismo , Tetrazóis/farmacologia , Tioureia/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo/fisiologia , Canais de Potássio Cálcio-Ativados/efeitos dos fármacos , Ratos Sprague-Dawley , Tioureia/farmacologia
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