Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 204
Filtrar
Filtros adicionais











País/Região como assunto
Intervalo de ano
1.
Free Radic Biol Med ; 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31574344

RESUMO

Brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) pathway is associated with ischemic heart diseases (IHD). 7,8-dihydroxyflavone (7,8-DHF), BDNF mimetic, is a potent agonist of TrkB. We aimed to investigate the effects and the underlying mechanisms of 7,8-DHF on cardiac ischemia. Myocardial ischemic mouse model was induced by ligation of left anterior descending coronary artery. 7,8-DHF (5 mg/kg) was administered intraperitoneally two days after ischemia for four weeks. Echocardiography, HE staining and transmission electron microscope were used to examine the function, histology and ultrastructure of the heart. H9c2 cells were treated with hydrogen peroxide (H2O2), 7,8-DHF or TrkB inhibitor ANA-12. The effects of 7,8-DHF on cell viability, mitochondrial membrane potential (MMP) and mitochondrial superoxide generation were examined. Furthermore, mitochondrial fission and protein expression of mitochondrial dynamics (Mfn2 [mitofusin 2], OPA1 [optic atrophy 1], Drp1 [dynamin-related protein 1] and Fis-1 [fission 1]) was detected by mitotracker green staining and western blot, respectively. 7,8-DHF attenuated cardiac dysfunction and cardiomyocyte abnormality of myocardial ischemic mice. Moverover, 7,8-DHF increased cell viability and reduced cell death accompanied by improving MMP, inhibiting mitochondrial superoxide and preventing excessive mitochondrial fission of H2O2-treated H9c2 cells. The cytoprotective effects of 7,8-DHF were antagonized by ANA-12. Mechanistically, 7,8-DHF repressed OMA1-dependent conversion of L-OPA1 into S-OPA1, which was abolished by Akt inhibitor. In conclusion, 7,8-DHF protects against cardiac ischemic injury by inhibiting the proteolytic cleavage of OPA1. These findings provide a novel pharmacological effect of 7,8-DHF on mitochondrial dynamics and a new potential target for IHD.

2.
J Sci Food Agric ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512250

RESUMO

BACKGROUND: Composite gels were individually prepared from 20 g kg-1 myofibrillar protein (MP) imbedded with typical native starch (potato, tapioca, rice or corn starch) in 0.6 mol L-1 NaCl at pH 6.2. The gel strength, water holding capacity, rheological properties, and microstructure of the obtained myofibrillar protein-starch composite gels were evaluated. RESULTS: Tapioca starch improved (P<0.05) gel strength and water holding capacity of MP composite gel at 80 °C. Rheological properties of MP-starch composites differed significantly with the addition of different types of native starch. Additionally, the promoting effect of starch on the storage modulus of the composite gels positively correlated with the gelatinization properties of different typical starch. Environmental scanning electron microscopy showed that the filling effect of starch on the composite gel was related to the pasting temperature and particle size of typical starch, with almost no particles forming at 80 °C. Moreover, the addition of starch changed the relaxation peak area and increased the relaxation time in NMR tests, which suggested that starch could improve the water holding capacity of MP-starch composite gels. CONCLUSION: Different typical native starch has varied impacts on the gel strength, water holding capacity, rheological properties, and microstructure of MP gels, indicating the potential and feasibility of these typical native starches as addition agent to modify the textural properties in comminuted meat products. This article is protected by copyright. All rights reserved.

3.
Exp Cell Res ; : 111613, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31494095

RESUMO

The lipotoxicity is considered as one of the risk for diabetes. Here we report C-type lectin domain family 11, member A (Clec11a) as a new regulator in islet playing a protective role in lipotoxicity induced dysfunction. Islet transcriptome sequencing was performed using the high-fat diet induced obesity (DIO) mice model. We found a significant decrease of Clec11a expression in islets of DIO mice compared to normal control mice, which was further confirmed by real-time PCR. Immunostaining demonstrated the localization of the Clec11a protein in mouse islets. Administration of recombinant human Clec11a (rClec11a) protein promoted the proliferation of islet cells and rescued the inhibition of fatty acid on cell proliferation, which involved the activation of Erk signaling pathway. We also found that the rClec11a altered the expression of genes involved in lipid metabolism.

4.
Chemistry ; 25(52): 12137-12144, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31276238

RESUMO

Isomerism heavily influences the optoelectronic properties and self-assembly behavior of compounds and subsequently affects their device performance. Herein, two pairs of isomeric perylene diimide (PDI) dimers, PDI and PDI2, were designed and synthesized. The electron-deficient 9,10-anthraquinone group was employed as the bridge, and thus, the resultant dimers exhibited an acceptor-acceptor-acceptor (A-A-A) structure. To determine the isomeric effects on the optoelectronic properties and photovoltaic performance of these dimers, their absorptivity, luminescence, and redox behavior were studied. Bulk heterojunction organic solar cells based on these four dimers were fabricated and measured. The two PDI dimers exhibited clear differences in photovoltaic performance, whereas the two PDI2 analogues showed similar power conversion efficiencies (PCEs). The PCEs of the two PDI2 dimers are much higher than those of the PDI dimers. These results illustrate that the isomeric effect of PDI dimers is much larger than that of PDI2 dimers on the device performance, and proper expansion of conjugation could improve the device performance.

5.
Nat Prod Res ; : 1-8, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31328555

RESUMO

One new oleanane-type nortriterpene, rosanortriterpene A (1), and one new ursane-type nortriterpene, rosanortriterpene B (2), were isolated from the fruits of Rosa laevigata var. leiocapus. The structures of 1-2 were fully characterised on the basis of extensive spectroscopic analysis, including IR, HRESIMS, as well as 1D and 2D NMR spectral data (HSQC, 1H-1H COSY, and HMBC). To the best of our knowledge, this represents the first study on the chemical constituents of R. laevigata var. leiocapus. Compounds 1-2 exhibited moderate inhibitory effects on NO production in LPS stimulated RAW264.7 cells with IC50 values of 29.29 ± 3.64 and 14.28 ± 1.20 µM, respectively.

6.
ACS Nano ; 13(6): 7191-7201, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31180625

RESUMO

Three-dimensional (3D) DNA scaffolds with well-defined structure and high controllability hold promising potentials for biosensing and drug delivery. However, most of 3D DNA scaffolds can detect only a single type of molecule with the involvement of complex logic operations. Herein, we develop a 3D DNA nanostructure with the capability of multiplexed detection by exploiting a multistep Förster resonance energy transfer (FRET). The tetrahedron-structured DNA is constructed by four oligonucleotide strands and is subsequently conjugated to a streptavidin-coated quantum dot (QD) to obtain a QD-Cy3-Texas Red-Cy5 tetrahedron DNA. This QD-Cy3-Texas Red-Cy5 tetrahedral DNA nanostructure has well-defined dye-to-dye spacing and high controllability for energy transfer between intermediary acceptors and terminal acceptors, enabling the generation of multistep FRET between the QD and three dyes (i.e., Cy3, Texas Red, and Cy5) for simultaneous detection of multiple endonucleases and methyltransferases even in complex biological samples as well as the screening of multiple enzyme inhibitors.

7.
Eur J Pharmacol ; 857: 172449, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207208

RESUMO

Endoplasmic reticulum stress (ERS)-induced cardiomyocyte apoptosis plays an important role in the pathological process following myocardial infarction (MI). Macrophages that express microRNA-155 (miR-155) mediate cardiac inflammation, fibrosis, and hypertrophy. Therefore, we investigated if miR-155 regulates ERS-induced cardiomyocyte apoptosis after MI using a mouse model, lipopolysaccharide (LPS)-induced rat bone marrow derived macrophages (BMDMs)and hypoxia-induced neonatal rat cardiomyocytes (NRCMs). In vivo, miR-155 levelswere significantly higher in the MI group compared to the sham group. MI increasedmacrophage infiltration, nuclear factor-κB (NF-κB) activation, ERS induced-apoptosis, and SOCS1 expression, all of which were attenuated by the miR-155 antagomir, with the exception of SOCS1 expression. Additionally, post-MI cardiac dysfunction was significantly improved by miR-155 inhibition. In vitro, LPS upregulated miR-155 expression in BMDMs, and the miR-155 antagomir decreased LPS-induced macrophage inflammation and NF-κB pathway activation, but increased expression of SOCS1. Hypoxia increased NF-κB pathway activation, ERS marker expression, and apoptosis in NRCMs. Interestingly, conditioned medium from LPS-induced macrophages in combination with the miR-155 antagomir decreased, while the miR-155 agomir increased, the hypoxia-induced effects in NRCM's. The miR-155 agomir effects were reversed by inhibiting the NF-κB pathway in cardiomyocytes. Moreover, SOCS1 knockdown in LPS-induced macrophages promoted NF-κB pathway activation and ERS-induced cardiomyocyte apoptosis in the hypoxia-induced NRCMs, but the SOCS1-siRNA-induced effects were markedly decreased by miR-155 antagomir treatment. These data suggest that miR-155 inhibition attenuates ERS-induced cardiomyocyte apoptosis after MI via reducing macrophage inflammation through the SOCS1/NF-κB pathway.

8.
Oxid Med Cell Longev ; 2019: 4579806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191799

RESUMO

Acute myocardial infarction (AMI) is the leading cause of sudden death worldwide. MicroRNA-155 (miR-155) has been reported to target antiapoptotic genes in various diseases models, but the functional role of miR-155 in response to MI injury needs further investigations. This study investigated the role of miR-155 in myocardial ischemia injury. TUNEL and flow cytometry were performed to measure cell apoptosis. Western blot analysis was employed to detect protein expressions of Bcl-2, XIAP, Bax, and caspase-3. qRT-PCR was used to quantify miRNA levels. We showed that miR-155 was dynamically elevated in murine hearts subjected to MI and in neonatal rat ventricular cardiomyocyte (NRVM) injury induced by hydrogen peroxide (H2O2). In response to H2O2, the silencing of miR-155 using AMO-155 (antisense inhibitor oligodeoxyribonucleotides) significantly increased cell viability and reduced cell apoptosis. Moreover, AMO-155 reversed the H2O2-induced downregulation of Bcl-2 and XIAP and upregulation of Bax and cleaved-caspase-3. Further study revealed that AMO-155 resulted in a decrease of H2O2-induced JC-1-labelled monomeric cell number. In addition, AMO-155 markedly decreased infarct size, ameliorated impaired cardiac function, and significantly reduced apoptotic cell percentages in MI mice heart. The RNA-binding protein Quaking (QKI) was predicted as a target gene of miR-155 through bioinformatic analysis, and AMO-155 attenuated the downregulation of QKI in H2O2-treated cardiomyocytes and MI mice heart. Knockdown of QKI by siRNA abolished the antiapoptotic effects of AMO-155. Taken together, miR-155 is upregulated in the MI heart and NRVMs in response to H2O2 stress, and downregulating of miR-155 protects cardiomyocytes against apoptosis. Mechanistically, it is probably due to the repression of QKI signaling pathway.

9.
J Agric Food Chem ; 67(26): 7249-7257, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244201

RESUMO

The duration of the rice growth phase has always been an important target trait. The identification of mutations in rice that alter these processes and result in a shorter growth phase could have potential benefits for crop production. In this study, we isolated an early aging rice mutant, pe-1, with light green leaves, using γ-mutated indica rice cultivar and subsequent screening methods, which is known as the phytochrome synthesis factor Se5 that controls rice flowering. The pe-1 plant is accompanied by a decreased chlorophyll content, an enhanced photosynthesis, and a decreased pollen fertility. PE-1, a close homologue of HY1, is localized in the chloroplast. Expression pattern analysis indicated that PE-1 was mainly expressed in roots, stems, leaves, leaf sheaths, and young panicles. The knockout of PE-1 using the CRISPR/Cas9 system decreased the chlorophyll content and downregulated the expression of PE-1-related genes. Furthermore, the chloroplasts of pe-1 were filled with many large-sized starch grains, and the number of osmiophilic granules (a chloroplast lipid reservoir) was significantly decreased. Altogether, our findings suggest that PE-1 functions as a master regulator to mediate in chlorophyll biosynthesis and photosynthetic pathways.


Assuntos
Cloroplastos/metabolismo , Heme Oxigenase-1/metabolismo , Oryza/enzimologia , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Clorofila/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas , Heme Oxigenase-1/genética , Mutação , Oryza/genética , Oryza/metabolismo , Fotossíntese , Proteínas de Plantas/genética
10.
Pharmacol Res ; 146: 104315, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207343

RESUMO

Aloe-emodin (AE) is an anthraquinone derived from rhubarb and has a variety of pharmacological actions. However, the role of AE in regulating ischemic heart diseases is still unclear. The present study investigated the effect of AE on cardiac injuries induced by myocardial infarction (MI) in vivo and oxidative insults in vitro and explored the mechanisms involved. TUNEL and Flow cytometry were performed to measure cell apoptosis. Western blot analysis was employed to detect expression of Bcl-2, Bax and Caspase-3 proteins. Real-time PCR was used to quantify the microRNAs levels. Our data showed that AE protected neonatal rat ventricular myocytes (NRVMs) from hydrogen peroxide (H2O2) induced apoptosis and significantly inhibited H2O2-induced reactive oxygen species (ROS) elevation. Furthermore, AE treatment significantly reversed H2O2-induced upregulation of Bax/Bcl-2 and the loss of mitochondrial membrane potential. In vivo, AE treatment significantly reduced infarct size, ameliorated impaired cardiac function and obviously decreased cardiac apoptosis and oxidative stress in MI mice heart. Meanwhile, AE restored H2O2-induced downregulation of miR-133, and transfection with miR-133 inhibitor abolished the anti-apoptotic and anti-oxidative effects of AE. Moreover, AE prevented H2O2-induced increase in caspase-3 activity, which was diminished by application of miR-133 inhibitor. Our results indicate that AE protectes against myocardial infarction via the upregulation of miR-133, inhibition of ROS production and suppression of caspase-3 apoptotic signaling pathway.

11.
BMC Complement Altern Med ; 19(1): 127, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31196042

RESUMO

BACKGROUND: Xin-Ji-Er-Kang (XJEK) is a Chinese herbal formula, which has been reported to exert effective protection against cardiovascular diseases, including hypertension and myocarditis. METHODS: Cultured human umbilical vascular endothelial cells (HUVECs) were treated with angiotensin II (Ang II) and different concentrations of aqueous layer extracts (AqE). Subsequently nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) expression levels were detected. In addition, fifty Kunming mice were randomized into control, Nω-nitro-L-arginine methyl ester (L-NAME), L-NAME+AqE, L-NAME+XJEK and L-NAME+fosinopril treatment groups. Following 8 weeks of treatment, the cardiac hemodynamic index was measured, relaxation of the aorta was examined and pathological changes were observed. Colorimetric analysis and enzyme linked immunosorbent assay (ELISA) were applied to determine the relevant indicators in plasma and cardiac tissues. RESULTS: The in vitro study results demonstrated that AqE could preserve endothelial function (NO, 21.05 ± 2.03 vs. 8.64 ± 0.59; eNOS, 1.08 ± 0.17 vs.0.73 ± 0.06). In addition, the in vivo results demonstrated that compared with the control group, treatment with AqE could enhance a high hemodynamic state (left ventricular systolic pressure, 116.76 ± 9.96 vs.114.5 ± 15.16), improve endothelial function (NO, 7.98 ± 9.64 vs. 1.66 ± 3.11; eNOS, 19.78 ± 3.18 vs.19.38 ± 3.85), suppress oxidative stress (OS) (superoxide dismutase, 178.17 ± 13.78 vs. 159.38 ± 18.86; malondialdehyde, 0.77 ± 0.13 vs.1.25 ± 0.36) and reverse cardiovascular remodeling. CONCLUSION: Polysaccharide from XJEK exerts protective effects against Ang II-induced injury in HUVECs and L-NAME-induced hypertension in mice and the underlying mechanism may be attributed to improving endothelial dysfunction, OS and the inflammation status in mice.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Remodelação Vascular/efeitos dos fármacos , Angiotensina II , Animais , Aorta/efeitos dos fármacos , Arginina/análogos & derivados , Arginina/sangue , Pressão Sanguínea/efeitos dos fármacos , Citocinas/metabolismo , Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão/induzido quimicamente , Inflamação/tratamento farmacológico , Masculino , Malondialdeído/sangue , Camundongos , Miocárdio/metabolismo , NG-Nitroarginina Metil Éster , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , Superóxido Dismutase/sangue
12.
Chemosphere ; 234: 830-836, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31247493

RESUMO

Poor soil has restricted the crop production in semiarid soil. Fulvic acid (FA) is considered to play an significant role in soil fertility. The amount and structure of FA after application of different organic wastes (OWs) was assessed in this work. Six treatments were involved in this experiment: chemical fertilizer combined with chicken manure (CM), sheep manure (SM), maize straw (MS), fodder grass (FG), and tree leaves (TL), while chemical fertilizer only was used as control (CK). The soil FA content (P < 0.05) after the application of TL was the highest than other OWs. The E4/E6 ratios, ΔlogK values, aliphatic C/aromatic C ratios of soil FA after the application of TL were the lowest than other OWs, whereas the C/H ratio was the highest. The specific fluorescence intensities (SFI) of peak A (Ex/Em 260-265/415-430 nm) and peak B (Ex/Em 310-315/415-430 nm) from EEM fluorescence spectrum of FA were the lowest after the application of TL. In conclusion, the application of TL was the most effective for improving FA accumulation, and making FA complex and stability. Thus, TL is the recommended OW for use in semiarid soil under plastic mulched drip irrigation conditions.

13.
Eur J Radiol ; 115: 39-45, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31084757

RESUMO

OBJECTIVES: To explore whether MRI and radiomic features can differentiate uterine sarcoma from atypical leiomyoma. And to compare diagnostic performance of radiomic model with radiologists. METHODS: 78 patients (29 sarcomas, 49 leiomyomas) imaged with pelvic MRI prior to surgery were included in this retrospective study. Certain clinical and MRI features were evaluated for one lesion per patient. Radiological diagnosis was made based on MRI features. A radiomic model using automated texture analysis based on ADC maps was built to predict pathological results. The association between MRI features and pathological results was determined by multivariable logistic regression after controlling for other variables in univariate analyses with P < 0.05. The diagnostic efficacy of radiologists and radiomic model were compared by area under the receiver-operating characteristic curve (AUC), sensitivity, specificity and accuracy. RESULTS: In univariate analyses, patient's age, menopausal state, intratumor hemorrhage, tumor margin and uterine endometrial cavity were associated with pathological results, P < 0.05. Patient's age, tumor margin and uterine endometrial cavity remained significant in a multivariable model, P < 0.05. Diagnosis efficacy of radiologists based on MRI reached an AUC of 0.752, sensitivity of 58.6%, specificity of 91.8%, and accuracy of 79.5%. The optimal radiomic model reached an AUC of 0.830, sensitivity of 76.0%, average specificity of 73.2%, and accuracy of 73.9%. CONCLUSIONS: Ill-defined tumor margin and interrupted uterine endometrial cavity of older women were predictors of uterine sarcoma. Radiomic analysis was feasible. Optimal radiomic model showed comparable diagnostic efficacy with experienced radiologists.


Assuntos
Leiomioma/patologia , Sarcoma/patologia , Neoplasias Uterinas/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Int J Neurosci ; 129(10): 1004-1012, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31070081

RESUMO

Purpose: This study aimed to assess the clinical value of ocular vestibular evoked myogenic potential (oVEMP) and cervical vestibular evoked myogenic potential (cVEMP) for monitoring the rehabilitation of vestibular function in patients treated for peripheral vertigo. Materials and methods: Fifteen patients who had been diagnosed with peripheral vertigo and showed no VEMP response on the affected side but exhibited symptom alleviation and VEMP responses after therapies were retrospectively enrolled. We analyzed the restoration and parameters of their VEMP response. Results: After treatment, six patients with sudden sensorineural hearing loss showed VEMP recovery, including two with both oVEMP and cVEMP recovery, three with oVEMP recovery only, and one with cVEMP recovery only. Two patients with Meniere's disease (MD) showed cVEMP recovery, while the other three MD patients showed oVEMP recovery. Three patients with herpes zoster oticus exhibited cVEMP recovery. One patient with vestibular neuritis exhibited cVEMP recovery. Among the patients with cVEMP and/or oVEMP restoration, most patients presented normal VEMP parameters; however, some patients showed abnormal VEMP parameters after treatment. Conclusion: Combined oVEMP and cVEMP are objective tools for assessing vestibular otolithic end organ function during dynamic functional recovery from vestibular diseases.

15.
J Cell Physiol ; 234(10): 18731-18747, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30953351

RESUMO

The timely regulation of inflammatory M1 macrophage polarization toward regenerative M2 macrophages suggests the possibility of immunotherapy after myocardial infarction (MI). C1q/TNF-related protein-9 (CTRP9) has anti-inflammatory effects and can ameliorate heart function in mice after long-term myocardial infarction. The role of CTRP9 in macrophage polarization remains completely unclear. This study determined whether CTRP9 can preserve post-MI early cardiac function through the regulation of macrophage polarization. In the present study, an adenovirus-delivered CTRP9 supplement promoted macrophage polarization at Day 3 post MI and improved cardiac function at Day 7 post MI. Pretreatment with gCTRP9 promoted the M1 to M2 polarization transition and attenuated inflammation after lipopolysaccharide + interferon-γ stimulation; the effects were partly abrogated by the adenosine monophosphate kinase (AMPK) inhibitor compound C and were obviously reinforced by pyrrolidine dithiocarbamate, a nuclear factor-κB (NF-κB) inhibitor. Meanwhile, CTPR9 markedly reduced the expression of toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and NF-κB p65 phosphorylation by promoting AMPK phosphorylation in vivo and in vitro. Moreover, the competitive binding of gCTRP9 and LPS to the myeloid differentiation protein 2 (MD2)/TLR4 complex was associated with direct binding to MD2, thereby inhibiting the downstream signaling molecule MyD88. Taken together, we demonstrated that CTRP9 improved post-MI early cardiac function, at least in part, by modulating M1/M2 macrophage polarization, largely via the TLR4/MD2/MyD88 and AMPK-NF-κB pathways.

16.
Planta ; 250(1): 281-298, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31025197

RESUMO

MAIN CONCLUSION: The alpha-amylase and beta-amylase genes have been identified from tea plants, and their bioinformatic characteristics and expression patterns provide a foundation for further studies to elucidate their biological functions. Alpha-amylase (AMY)- and beta-amylase (BAM)-mediated starch degradation plays central roles in carbohydrate metabolism and participates extensively in the regulation of a wide range of biological processes, including growth, development and stress response. However, the AMY and BAM genes in tea plants (Camellia sinensis) are poorly understood, and the biological functions of these genes remain to be elucidated. In this study, three CsAMY and nine CsBAM genes from tea plants were identified based on genomic and transcriptomic database analyses, and the genes were subjected to comprehensive bioinformatic characterization. Phylogenetic analysis showed that the CsAMY proteins could be clustered into three different subfamilies, and nine CsBAM proteins could be classified into four groups. Putative catalytically active proteins were identified based on multiple sequence alignments, and the tertiary structures of these proteins were analyzed. Cis-element analysis indicated that CsAMY and CsBAM were extensively involved in tea plant growth, development and stress response. In addition, the CsAMY and CsBAM genes were differentially expressed in various tissues and were regulated by stress treatments (e.g., ABA, cold, drought and salt stress), and the expression patterns of these genes were associated with the postharvest withering and rotation processes. Taken together, our results will enhance the understanding of the roles of the CsAMY and CsBAM gene families in the growth, development and stress response of tea plants and of the potential functions of these genes in determining tea quality during the postharvest processing of tea leaves.


Assuntos
Camellia sinensis/enzimologia , Regulação da Expressão Gênica de Plantas , alfa-Amilases/metabolismo , beta-Amilase/metabolismo , Camellia sinensis/genética , Camellia sinensis/fisiologia , Secas , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Estresse Fisiológico , alfa-Amilases/genética , beta-Amilase/genética
17.
Eur J Pharmacol ; 851: 122-132, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30721702

RESUMO

Inflammation plays an important role in sympathetic neural remodeling induced by myocardial infarction (MI). MiR-155 is a vital regulator of inflammatory responses, and macrophage-secreted miR-155 promotes cardiac fibrosis and hypertrophy. However, whether miR-155 influences MI-induced sympathetic neural remodeling is not clear. Therefore, we examined the role of miR-155 in MI-induced sympathetic neural remodeling and the related mechanisms in both an mouse model and in lipopolysaccharide (LPS)-stimulated bone marrow-derived macrophages (BMDMs). Our data showed that miR-155 expression was significantly enhanced in the myocardial tissues of MI mice compared to sham mice. Also, MI up-regulated the electrophysiological parameters, M1 macrophage polarization, inflammatory responses, and suppressor of cytokine signaling 1 (SOCS1) expression, which coincided with the increased expression of sympathetic nerve remodeling markers(nerve growth factor, tyrosine hydroxylase and growth-associated protein 43). Except for SOCS1, these proteins were attenuated by miR-155 antagomir. In vitro, LPS-stimulation promoted miR-155 expression in BMDMs. Consistent with the in vivo findings, miR-155 antagomir diminished the LPS-induced M1 macrophage polarization, nuclear factor (NF)-κB activation, and the expression of pro-inflammatory factors and nerve growth factor; but it increased the expression of SOCS1. Inversely, miR-155 agomir significantly potentiated LPS-induced pathophysiological effects in BMDMs. MiR-155 agomir-induced effects were reversed by the NF-κB inhibitor. Mechanistically, treatment with siRNA against SOCS1 augmented the aforementioned LPS-mediated activities, which were antagonized by the addition of miR-155 antagomir. In conclusion, miR-155 inhibition downregulated NGF expression via decreasing M1 macrophage polarization and inflammatory responses dependent on the SOCS1/NF-κB pathway, subsequently diminishing MI-induced sympathetic neural remodeling and ventricular arrhythmias (VAs).


Assuntos
Macrófagos/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Infarto do Miocárdio/patologia , Plasticidade Neuronal/efeitos dos fármacos , Sistema Nervoso Simpático/fisiopatologia , Animais , Antagomirs/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/patologia , Inflamação/fisiopatologia , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Fator de Crescimento Neural/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos
19.
Biochim Biophys Acta Mol Basis Dis ; 1865(6): 1113-1125, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30779947

RESUMO

Vasculogenic mimicry (VM) results in the formation of an alternative circulatory system that can improve the blood supply to multiple malignant tumors, including hepatocellular carcinoma (HCC). However, the potential mechanisms of RhoC/ROCK in VM have not yet been investigated in HCC. Here, RhoC expression was upregulated in HCC tissues, especially the VM-positive (VM+) group, compared to noncancerous tissues (P < 0.01), and patients with high expression of RhoC had shorter survival times (P < 0.001). The knockdown of RhoC via short hairpin RNA (shRNA) in SK-Hep-1 cells significantly decreased VM formation and cell motility. In contrast, cell motility and VM formation were remarkably enhanced when RhoC was overexpressed in HepG2 cells. To further assess the potential role of ROCK1 and ROCK2 on VM, we stably knocked down ROCK1 or ROCK2 in MHCC97H cells. Compared to ROCK1 shRNA, ROCK2 shRNA could largely affect VM formation, cell motility and the key VM factors, as well as the epithelial-mesenchymal transition (EMT) markers in vitro and in vivo. Moreover, p-ERK, p-MEK, p-FAK, p-paxillin, MT1-MMP and MMP2 levels were clearly altered following the overexpression of RhoC, but ROCK2 shRNA had little effect on the expression of p-FAK, which indicated that RhoC regulates FAK/paxillin signaling, but not through ROCK2. In conclusion, our results show that RhoC/ROCK2 may have a major effect on VM in HCC via ERK/MMPs signaling and might be a potential therapeutic target for the treatment of HCC.

20.
Proc Natl Acad Sci U S A ; 116(11): 5170-5175, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30804201

RESUMO

The transient receptor potential vanilloid-1 (TRPV1) ion channel is essential for sensation of thermal and chemical pain. TRPV1 activation is accompanied by Ca2+-dependent desensitization; acute desensitization reflects rapid reduction in channel activity during stimulation, whereas tachyphylaxis denotes the diminution in TRPV1 responses to repetitive stimulation. Acute desensitization has been attributed to conformational changes of the TRPV1 channel; however, the mechanisms underlying the establishment of tachyphylaxis remain to be defined. Here, we report that the degree of whole-cell TRPV1 tachyphylaxis is regulated by the strength of inducing stimulation. Using light-sheet microscopy and pH-sensitive sensor pHluorin to follow TRPV1 endocytosis and exocytosis trafficking, we provide real-time information that tachyphylaxis of different degrees concurs with TRPV1 recycling to the plasma membrane in a proportional manner. This process controls TRPV1 surface expression level thereby the whole-cell nociceptive response. We further show that activity-gated TRPV1 trafficking associates with intracellular Ca2+ signals of distinct kinetics, and recruits recycling routes mediated by synaptotagmin 1 and 7, respectively. These results suggest that activity-dependent TRPV1 recycling contributes to the establishment of tachyphylaxis.


Assuntos
Membrana Celular/metabolismo , Endocitose , Canais de Cátion TRPV/metabolismo , Taquifilaxia , Animais , Sinalização do Cálcio , Exocitose , Células HEK293 , Humanos , Luz , Transporte Proteico , Ratos , Sinaptotagminas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA