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1.
Biochem Biophys Res Commun ; 693: 149368, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38091838

RESUMO

Tunneling nanotubes (TNTs) are elastic tubular structures that physically link cells, facilitating the intercellular transfer of organelles, chemical signals, and electrical signals. Despite TNTs serving as a multifunctional pathway for cell-cell communication, the transmission of mechanical signals through TNTs and the response of TNT-connected cells to these forces remain unexplored. In this study, external mechanical forces were applied to induce TNT bending between rat kidney (NRK) cells using micromanipulation. These forces, transmitted via TNTs, induced reduced curvature of the actin cortex and increased membrane tension at the TNT-connected sites. Additionally, TNT bending results in an elevation of intracellular calcium levels in TNT-connected cells, a response attenuated by gadolinium ions, a non-selective mechanosensitive calcium channel blocker. The degree of TNT deflection positively correlated with decreased actin cortex curvature and increased calcium levels. Furthermore, stretching TNT due to the separation of TNT-connected cells resulted in decreased actin cortex curvature and increased intracellular calcium in TNT-connected cells. The levels of these cellular responses depended on the length changes of TNTs. Moreover, TNT connections influence cell migration by regulating cell rotation, which involves the activation of mechanosensitive calcium channels. In conclusion, our study revealed the transmission of mechanical signals through TNTs and the subsequent responses of TNT-connected cells, highlighting a previously unrecognized communication function of TNTs. This research provides valuable insights into the role of TNTs in long-distance intercellular mechanical signaling.


Assuntos
Actinas , Nanotubos , Ratos , Animais , Cálcio/metabolismo , Comunicação Celular/fisiologia , Linhagem Celular , Nanotubos/química
2.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34470821

RESUMO

Mechanical forces generated by cells and the tension of the extracellular matrix (ECM) play a decisive role in establishment, homeostasis maintenance, and repair of tissue morphology. However, the dynamic change of cell-derived force during large-scale remodeling of soft tissue is still unknown, mainly because the current techniques of force detection usually produce a nonnegligible and interfering feedback force on the cells during measurement. Here, we developed a method to fabricate highly stretchable polymer-based microstrings on which a microtissue of fibroblasts in collagen was cultured and allowed to contract to mimic the densification of soft tissue. Taking advantage of the low-spring constant and large deflection range of the microstrings, we detected a strain-induced contraction force as low as 5.2 µN without disturbing the irreversible densification. Meanwhile, the microtissues displayed extreme sensitivity to the mechanical boundary within a narrow range of tensile stress. More importantly, results indicated that the cell-derived force did not solely increase with increased ECM stiffness as previous studies suggested. Indeed, the cell-derived force and collagen tension exchanged dramatically in dominating the microtissue strain during the densification, and the proportion of cell-derived force decreased linearly as the microtissue densified, with stiffness increasing to ∼500 Pa. Thus, this study provides insights into the biomechanical cross-talk between the cells and ECM of extremely soft tissue during large-extent densification, which may be important to guide the construction of life-like tissue by applying appropriate mechanical boundary conditions.


Assuntos
Colágeno/química , Matriz Extracelular/química , Fenômenos Biomecânicos , Desenvolvimento Embrionário , Fenômenos Mecânicos , Engenharia Tecidual
3.
J Med Internet Res ; 26: e48356, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38533835

RESUMO

BACKGROUND: This paper explores the widely discussed relationship between electronic media use and sleep quality, indicating negative effects due to various factors. However, existing meta-analyses on the topic have some limitations. OBJECTIVE: The study aims to analyze and compare the impacts of different digital media types, such as smartphones, online games, and social media, on sleep quality. METHODS: Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the study performed a systematic meta-analysis of literature across multiple databases, including Web of Science, MEDLINE, PsycINFO, PubMed, Science Direct, Scopus, and Google Scholar, from January 2018 to October 2023. Two trained coders coded the study characteristics independently. The effect sizes were calculated using the correlation coefficient as a standardized measure of the relationship between electronic media use and sleep quality across studies. The Comprehensive Meta-Analysis software (version 3.0) was used to perform the meta-analysis. Statistical methods such as funnel plots were used to assess the presence of asymmetry and a p-curve test to test the p-hacking problem, which can indicate publication bias. RESULTS: Following a thorough screening process, the study involved 55 papers (56 items) with 41,716 participants from over 20 countries, classifying electronic media use into "general use" and "problematic use." The meta-analysis revealed that electronic media use was significantly linked with decreased sleep quality and increased sleep problems with varying effect sizes across subgroups. A significant cultural difference was also observed in these effects. General use was associated with a significant decrease in sleep quality (P<.001). The pooled effect size was 0.28 (95% CI 0.21-0.35; k=20). Problematic use was associated with a significant increase in sleep problems (P≤.001). The pooled effect size was 0.33 (95% CI 0.28-0.38; k=36). The subgroup analysis indicated that the effect of general smartphone use and sleep problems was r=0.33 (95% CI 0.27-0.40), which was the highest among the general group. The effect of problematic internet use and sleep problems was r=0.51 (95% CI 0.43-0.59), which was the highest among the problematic groups. There were significant differences among these subgroups (general: Qbetween=14.46, P=.001; problematic: Qbetween=27.37, P<.001). The results of the meta-regression analysis using age, gender, and culture as moderators indicated that only cultural difference in the relationship between Eastern and Western culture was significant (Qbetween=6.69; P=.01). All funnel plots and p-curve analyses showed no evidence of publication and selection bias. CONCLUSIONS: Despite some variability, the study overall confirms the correlation between increased electronic media use and poorer sleep outcomes, which is notably more significant in Eastern cultures.


Assuntos
Qualidade do Sono , Mídias Sociais , Adulto , Feminino , Humanos , Masculino , Smartphone , Mídias Sociais/estatística & dados numéricos , Jogos de Vídeo/estatística & dados numéricos
4.
Cereb Cortex ; 32(16): 3488-3500, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34918060

RESUMO

During cortical development, the balance between progenitor self-renewal and neurogenesis is critical for determining the size/morphology of the cortex. A fundamental feature of the developing cortex is an increase in the length of G1 phase in RGCs over the course of neurogenesis, which is a key determinant of progenitor fate choice. How the G1 length is temporally regulated remains unclear. Here, Pdk1, a member of the AGC kinase family, was conditionally disrupted by crossing an Emx1-Cre mouse line with a Pdk1fl/fl line. The loss of Pdk1 led to a shorter cell cycle accompanied by increased RGC proliferation specifically at late rather than early/middle neurogenic stages, which was attributed to impaired lengthening of G1 phase. Coincidently, apical-to-basal interkinetic nuclear migration was accelerated in Pdk1 cKO cortices. Consequently, we detected an increased neuronal output at P0. We further showed the significant upregulation of the cell cycle regulator cyclin D1 and its activator Myc in the cKO cortices relative to those of control animals. Overall, we have identified a novel role for PDK1 in cortical neurogenesis. PDK1 functions as an upstream regulator of the Myc-cyclin D1 pathway to control the lengthening of G1 phase and the balance between RGC proliferation and differentiation.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Ciclina D1 , Neurogênese , Neuroglia , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Ciclina D1/metabolismo , Fase G1 , Camundongos , Neuroglia/citologia
5.
BMC Pulm Med ; 23(1): 272, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480065

RESUMO

BACKGROUND: This study aimed to investigate the effectiveness of neuromuscular electrical stimulation (NMES) blended with early rehabilitation on the diaphragm and skeletal muscle in sufferers on mechanical ventilation (MV). METHOD: This is a prospective randomized controlled study. Eighty patients on MV for respiratory failure were divided into a study group (40 cases) and a control group (40 cases) randomly. The study group adopted a treatment method of NMES combined with early rehabilitation and the control group adopted the method of early rehabilitation only. The diaphragmatic excursion (DE), diaphragmatic thickening fraction (DTF), variation of thickness of intercostal muscles (TIM), variation of thickness of rectus abdominis (TRA), and variation of the cross-sectional area of rectus femoris (CSA-RF) were measured to evaluate the therapeutic effect by ultrasound before and after intervention at the first day of MV, the 3rd and 7th day of intervention and the day discharged from ICU. RESULTS: No significant difference was found in the general demographic information and ultrasound indicators between the two groups before treatment (all P > 0.05). After treatment, the variation of DTF (0.15 ± 0.05% vs. 0.12 ± 0.04%, P = 0.034) was significantly higher in the study group than that in the control group on the day discharged from ICU. The variation of TRA (0.05 ± 0.09% vs. 0.10 ± 0.11%, P = 0.029) and variation of CSA-RF (0.13 ± 0.07% vs. 0.19 ± 0.08%, P < 0.001) in the study group were significantly lower than that in the control group. The duration of MV in the study group was significantly shorter than that in the control group [109.5 (88.0, 213.0) hours vs. 189.5 (131.5, 343.5) hours, P = 0.023]. The study group had better muscle strength score than the control group at discharge (52.20 ± 11.70 vs. 44.10 ± 15.70, P = 0.011). CONCLUSION: NMES combined with early rehabilitation therapy is beneficial in reducing muscle atrophy and improving muscle strength in mechanically ventilated patients. This treatment approach may provide a new option for patients to choose a rehabilitation program; however, more research is needed to fully evaluate the effectiveness of this treatment option.


Assuntos
Projetos de Pesquisa , Respiração Artificial , Humanos , Estudos Prospectivos , Prevenção Secundária , Estimulação Elétrica
6.
Brain Behav Immun ; 94: 437-457, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33588074

RESUMO

Hematoma size after intracerebral hemorrhage (ICH) significantly affects patient outcome. However, our knowledge of endogenous mechanisms that underlie hematoma clearance and the potential role of the anti-inflammatory cytokine interleukin-10 (IL-10) is limited. Using organotypic hippocampal slice cultures and a collagenase-induced ICH mouse model, we investigated the role of microglial IL-10 in phagocytosis ex vivo and hematoma clearance in vivo. In slice culture, exposure to hemoglobin induced IL-10 expression in microglia and enhanced phagocytosis that depended on IL-10-regulated expression of CD36. Following ICH, IL-10-deficient mice had more severe neuroinflammation, brain edema, iron deposition, and neurologic deficits associated with delayed hematoma clearance. Intranasal administration of recombinant IL-10 accelerated hematoma clearance and improved neurologic function. Additionally, IL-10-deficient mice had weakened in vivo phagocytic ability owing to decreased expression of microglial CD36. Moreover, loss of IL-10 significantly increased monocyte-derived macrophage infiltration and enhanced brain inflammation in vivo. These results indicate that IL-10 regulates microglial phagocytosis and monocyte-derived macrophage infiltration after ICH and that CD36 is a key phagocytosis effector regulated by IL-10. Leveraging the innate immune response to ICH by augmenting IL-10 signaling may provide a useful strategy for accelerating hematoma clearance and improving neurologic outcome in clinical translation studies.


Assuntos
Interleucina-10 , Microglia , Animais , Hemorragia Cerebral , Hematoma , Camundongos , Fagocitose
7.
Cereb Cortex ; 30(1): 406-420, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31504280

RESUMO

The six-layered neocortex consists of diverse neuron subtypes. Deeper-layer neurons originate from apical progenitors (APs), while upper-layer neurons are mainly produced by basal progenitors (BPs), which are derivatives of APs. As development proceeds, an AP generates two daughter cells that comprise an AP and a deeper-layer neuron or a BP. How the transition of APs to BPs is spatiotemporally regulated is a fundamental question. Here, we report that conditional deletion of phoshpoinositide-dependent protein kinase 1 (PDK1) in mouse developing cortex achieved by crossing Emx1Cre line with Pdk1fl/fl leads to a delayed transition of APs to BPs and subsequently causes an increased output of deeper-layer neurons. We demonstrate that PDK1 is involved in the modulation of the aPKC-Par3 complex and further regulates the asymmetric cell division (ACD). We also find Hes1, a downstream effecter of Notch signal pathway is obviously upregulated. Knockdown of Hes1 or treatment with Notch signal inhibitor DAPT recovers the ACD defect in the Pdk1 cKO. Thus, we have identified a novel function of PDK1 in controlling the transition of APs to BPs.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Células-Tronco Neurais/fisiologia , Neurônios/fisiologia , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/genética , Animais , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais
8.
BMC Anesthesiol ; 21(1): 276, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34753422

RESUMO

BACKGROUND: Treatment decisions in patients undergoing non-cardiac surgery are based on clinical assessment. The Revised Cardiac Risk Index (RCRI) is pragmatic and widely used but has only moderate discrimination. We aimed to test the efficacy of the CHA2DS2-VASc score and the combination of CHA2DS2-VASc and RCRI to predict perioperative risks for non-cardiac surgery. METHODS: This pre-specified analysis was performed in a retrospective cohort undergoing intra-abdominal surgery in our center from July 1st, 2007 to June 30th, 2008. The possible association between the baseline characteristics (as defined by CHA2DS2-VASc and RCRI) and the primary outcome of composite perioperative cardiac complications (myocardial infarction, cardiac ischemia, heart failure, arrhythmia, stroke, and/or death) and secondary outcomes of individual endpoints were explored using multivariate Logistic regression. The area under the receiver operating characteristic curve (C-statistic) was used for RCRI, CHA2DS2-VASc, and the combined models, and the net reclassification improvement (NRI) was calculated to assess the additional discriminative ability. RESULTS: Of the 1079 patients (age 57.5 ± 17.0 years), 460 (42.6%) were women. A total of 83 patients (7.7%) reached the primary endpoint. Secondary outcomes included 52 cardiac ischemic events, 40 myocardial infarction, 20 atrial fibrillation, 18 heart failure, four strokes, and 30 deaths. The endpoint events increased with the RCRI and CHA2DS2-VASc grade elevated (P < 0.05 for trend). The RCRI showed a moderate predictive ability with a C-statistics of 0.668 (95%CI 0.610-0.725) for the composite cardiac outcome. The C-statistics for the CHA2DS2-VASc was 0.765 (95% CI 0.709-0.820), indicating better performance than the RCRI (p = 0.011). Adding the CHA2DS2-VASc to the RCRI further increased the C-statistic to 0.774(95%CI 0.719-0.829), improved sensitivity, negative predictive value, and enhanced reclassification in reference to RCRI. Similar performance of the combined scores was demonstrated in the analysis of individual secondary endpoints. The best cut-off of a total of 4 scores was suggested for the combined CHA2DS2-VASc and RCRI in the prediction of the perioperative cardiac outcomes. CONCLUSIONS: The CHA2DS2-VASc score significantly enhanced risk assessment for the composite perioperative cardiovascular outcome in comparison to traditional RCRI risk stratification. Incorporation of CHA2DS2-VASc scores into clinical-decision making to improve perioperative management in patients undergoing non-cardiac surgery warrants consideration.


Assuntos
Abdome/cirurgia , Doenças Cardiovasculares/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Medição de Risco/métodos , Adulto , Idoso , Estudos de Coortes , Tomada de Decisões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Fatores de Risco
9.
Sensors (Basel) ; 21(4)2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33562003

RESUMO

Planar surfaces are prevalent components of man-made indoor scenes, and plane extraction plays a vital role in practical applications of computer vision and robotics, such as scene understanding, and mobile manipulation. Nowadays, most plane extraction methods are based on reconstruction of the scene. In this paper, plane representation is formulated in inverse-depth images. Based on this representation, we explored the potential to extract planes in images directly. A fast plane extraction approach, which employs the region growing algorithm in inverse-depth images, is presented. This approach consists of two main components: seeding, and region growing. In the seeding component, seeds are carefully selected locally in grid cells to improve exploration efficiency. After seeding, each seed begins to grow into a continuous plane in succession. Both greedy policy and a normal coherence check are employed to find boundaries accurately. During growth, neighbor coplanar planes are checked and merged to overcome the over-segmentation problem. Through experiments on public datasets and generated saw-tooth images, the proposed approach achieves 80.2% CDR (Correct Detection Rate) on the ABW SegComp Dataset, which has proven that it has comparable performance with the state-of-the-art. The proposed approach runs at 5 Hz on typical 680 × 480 images, which has shown its potential in real-time practical applications in computer vision and robotics with further improvement.

10.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669068

RESUMO

Tunneling nanotubes (TNTs) are recognized long membrane nanotubes connecting distance cells. In the last decade, growing evidence has shown that these subcellular structures mediate the specific transfer of cellular materials, pathogens, and electrical signals between cells. As intercellular bridges, they play a unique role in embryonic development, collective cell migration, injured cell recovery, cancer treatment resistance, and pathogen propagation. Although TNTs have been considered as potential drug targets for treatment, there is still a long way to go to translate the research findings into clinical practice. Herein, we emphasize the heterogeneous nature of TNTs by systemically summarizing the current knowledge on their morphology, structure, and biogenesis in different types of cells. Furthermore, we address the communication efficiency and biological outcomes of TNT-dependent transport related to diseases. Finally, we discuss the opportunities and challenges of TNTs as an exciting therapeutic approach by focusing on the development of efficient and safe drugs targeting TNTs.


Assuntos
Comunicação Celular/efeitos dos fármacos , Desenvolvimento de Medicamentos/métodos , Junções Intercelulares/metabolismo , Neoplasias/metabolismo , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Transporte Biológico Ativo/genética , Transporte Biológico Ativo/fisiologia , Comunicação Celular/genética , Humanos , Infecções/tratamento farmacológico , Infecções/metabolismo , Junções Intercelulares/efeitos dos fármacos , Junções Intercelulares/patologia , Junções Intercelulares/ultraestrutura , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo
11.
J Biol Chem ; 294(16): 6375-6386, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30792309

RESUMO

Contactin-associated protein 1 (CASPR1 or CNTNAP1) was recently reported to be expressed in brain microvascular endothelial cells (BMECs), the major component of the blood-brain barrier. To investigate CASPR1's physiological role in BMECs, here we used CASPR1 as a bait in a yeast two-hybrid screen to identify CASPR1-interacting proteins and identified the ß3 subunit of Na+/K+-ATPase (ATP1B3) as a CASPR1-binding protein. Using recombinant and purified CASPR1, RNAi, GST-pulldown, immunofluorescence, immunoprecipitation, and Na+/K+-ATPase activity assays, we found that ATP1B3's core proteins, but not its glycosylated forms, interact with CASPR1, which was primarily located in the endoplasmic reticulum of BMECs. CASPR1 knockdown reduced ATP1B3 glycosylation and prevented its plasma membrane localization, phenotypes that were reversed by expression of full-length CASPR1. We also found that the CASPR1 knockdown reduces the plasma membrane distribution of the α1 subunit of Na+/K+-ATPase, which is the major component assembled with ATP1B3 in the complete Na+/K+-ATPase complex. The binding of CASPR1 with ATP1B3, but not the α1 subunit, indicated that CASPR1 binds with ATP1B3 to facilitate the assembly of Na+/K+-ATPase. Furthermore, the activity of Na+/K+-ATPase was reduced in CASPR1-silenced BMECs. Interestingly, shRNA-mediated CASPR1 silencing reduced glutamate efflux through the BMECs. These results demonstrate that CASPR1 binds with ATP1B3 and thereby contributes to the regulation of Na+/K+-ATPase maturation and trafficking to the plasma membrane in BMECs. We conclude that CASPR1-mediated regulation of Na+/K+-ATPase activity is important for glutamate transport across the blood-brain barrier.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Membrana Celular/metabolismo , Células Endoteliais/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/citologia , Encéfalo/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Membrana Celular/genética , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Células Endoteliais/citologia , Deleção de Genes , Humanos , Microvasos/citologia , Microvasos/metabolismo , Ligação Proteica/fisiologia , Transporte Proteico/fisiologia , ATPase Trocadora de Sódio-Potássio/genética
12.
Cereb Cortex ; 29(3): 1185-1198, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29420689

RESUMO

3-Phosphoinositide-dependent protein kinase-1 (PDK1) is crucial for the development of the dentate gyrus (DG), the first gateway receiving afferent inputs from the entorhinal cortex. However, the role of PDK1 in DG development is unclear. In the present study, by crossing Pdk1fl/fl mice with the Emx1-cre line, we identified that the ablation of PDK1 disrupted the development of DG via decreasing the proliferation, and increasing the differentiation of dentate neural progenitor cells, downregulating AKT activity and upregulating GSK3ß signaling. Moreover, PDK1 deletion disrupted the distribution of Reelin+ cells and decreased the level of Reelin mRNA which may contribute to the defective migration of progenitor cells and the disrupted radial glial scaffolds. Furthermore, the inhibition of GSK3ß activity partially restored the decreased proliferation of primary neural stem cells in vitro. Taken together, our data indicated that the ablation of PDK1 affected the proliferation and differentiation of dentate neural progenitor cells in mice.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Giro Denteado/crescimento & desenvolvimento , Animais , Moléculas de Adesão Celular Neuronais/metabolismo , Diferenciação Celular , Proliferação de Células/fisiologia , Células Cultivadas , Giro Denteado/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/fisiologia , Neuroglia/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Reelina , Serina Endopeptidases/metabolismo , Transdução de Sinais
13.
BMC Genomics ; 20(1): 865, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730459

RESUMO

BACKGROUND: Gynostemma pentaphyllum is an important perennial medicinal herb belonging to the family Cucurbitaceae. Aerial stem-to-rhizome transition before entering the winter is an adaptive regenerative strategy in G. pentaphyllum that enables it to survive during winter. However, the molecular regulation of aerial stem-to-rhizome transition is unknown in plants. Here, integrated transcriptome and miRNA analysis was conducted to investigate the regulatory network of stem-to-rhizome transition. RESULTS: Nine transcriptome libraries prepared from stem/rhizome samples collected at three stages of developmental stem-to-rhizome transition were sequenced and a total of 5428 differentially expressed genes (DEGs) were identified. DEGs associated with gravitropism, cell wall biosynthesis, photoperiod, hormone signaling, and carbohydrate metabolism were found to regulate stem-to-rhizome transition. Nine small RNA libraries were parallelly sequenced, and seven significantly differentially expressed miRNAs (DEMs) were identified, including four known and three novel miRNAs. The seven DEMs targeted 123 mRNAs, and six pairs of miRNA-target showed significantly opposite expression trends. The GpmiR166b-GpECH2 module involved in stem-to-rhizome transition probably promotes cell expansion by IBA-to-IAA conversion, and the GpmiR166e-GpSGT-like module probably protects IAA from degradation, thereby promoting rhizome formation. GpmiR156a was found to be involved in stem-to-rhizome transition by inhibiting the expression of GpSPL13A/GpSPL6, which are believed to negatively regulate vegetative phase transition. GpmiR156a and a novel miRNA Co.47071 co-repressed the expression of growth inhibitor GpRAV-like during stem-to-rhizome transition. These miRNAs and their targets were first reported to be involved in the formation of rhizomes. In this study, the expression patterns of DEGs, DEMs and their targets were further validated by quantitative real-time PCR, supporting the reliability of sequencing data. CONCLUSIONS: Our study revealed a comprehensive molecular network regulating the transition of aerial stem to rhizome in G. pentaphyllum. These results broaden our understanding of developmental phase transitions in plants.


Assuntos
Regulação da Expressão Gênica de Plantas , Gynostemma/genética , MicroRNAs/genética , Componentes Aéreos da Planta/genética , RNA de Plantas/genética , Rizoma/genética , Transcriptoma , Adaptação Fisiológica/genética , Metabolismo dos Carboidratos/genética , China , Temperatura Baixa , Perfilação da Expressão Gênica , Biblioteca Gênica , Ontologia Genética , Gravitropismo/genética , Gynostemma/metabolismo , MicroRNAs/classificação , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Componentes Aéreos da Planta/metabolismo , Plantas Medicinais , RNA de Plantas/classificação , RNA de Plantas/metabolismo , Rizoma/metabolismo , Transdução de Sinais
14.
Brain Behav Immun ; 69: 568-581, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29458197

RESUMO

Intracerebral hemorrhage (ICH) is a detrimental type of stroke. Mouse models of ICH, induced by collagenase or blood infusion, commonly target striatum, but not other brain sites such as ventricular system, cortex, and hippocampus. Few studies have systemically investigated brain damage and neurobehavioral deficits that develop in animal models of ICH in these areas of the right hemisphere. Therefore, we evaluated the brain damage and neurobehavioral dysfunction associated with right hemispheric ICH in ventricle, cortex, hippocampus, and striatum. The ICH model was induced by autologous whole blood or collagenase VII-S (0.075 units in 0.5 µl saline) injection. At different time points after ICH induction, mice were assessed for brain tissue damage and neurobehavioral deficits. Sham control mice were used for comparison. We found that ICH location influenced features of brain damage, microglia/macrophage activation, and behavioral deficits. Furthermore, the 24-point neurologic deficit scoring system was most sensitive for evaluating locomotor abnormalities in all four models, especially on days 1, 3, and 7 post-ICH. The wire-hanging test was useful for evaluating locomotor abnormalities in models of striatal, intraventricular, and cortical ICH. The cylinder test identified locomotor abnormalities only in the striatal ICH model. The novel object recognition test was effective for evaluating recognition memory dysfunction in all models except for striatal ICH. The tail suspension test, forced swim test, and sucrose preference test were effective for evaluating emotional abnormality in all four models but did not correlate with severity of brain damage. These results will help to inform future preclinical studies of ICH outcomes.


Assuntos
Comportamento Animal/fisiologia , Encéfalo/patologia , Hemorragia Cerebral/fisiopatologia , Cognição/fisiologia , Emoções/fisiologia , Destreza Motora/fisiologia , Animais , Hemorragia Cerebral/patologia , Hemorragia Cerebral/psicologia , Modelos Animais de Doenças , Camundongos
16.
Neurobiol Dis ; 108: 173-182, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28830843

RESUMO

Tissue plasminogen activator (tPA) is administered after ischemic stroke to dissolve intravascular clots, but its use can lead to hemorrhagic transformation (HT). Therapeutic strategies to reduce hemorrhagic complications of tPA might be of benefit for stroke patients. Adenosine A2b receptor (A2bR) plays pivotal roles in regulating vascular protection in peripheral organs. This study explored whether A2bR agonist BAY 60-6583 reduces hemorrhage risk after tPA usage. Using a rat transient middle cerebral artery occlusion model, we showed that mRNA and protein expression of A2bR increased to a greater extent after ischemia-reperfusion than did expression of the other three adenosine receptors (A1, A2a, and A3). tPA administration reduced A2bR expression in ischemic brain microvessels. Post-treatment with BAY 60-6583 (1mg/kg) at the start of reperfusion reduced lesion volume in the absence or presence of tPA (10mg/kg) and attenuated brain swelling, blood-brain barrier disruption, and tPA-exacerbated HT at 24h. Additionally, BAY 60-6583 mitigated sensorimotor deficits in the presence of tPA. BAY 60-6583 inhibited tPA-enhanced matrix metalloprotease-9 activation, probably through elevation of tissue inhibitor of matrix metalloproteinases-1 expression, and thereby reduced degradation of tight junction proteins. These effects would likely protect cerebrovascular integrity. A2bR agonists as an adjuvant to tPA could be a promising strategy for decreasing the risk of HT during treatment for ischemic stroke.


Assuntos
Agonistas do Receptor A2 de Adenosina/farmacologia , Isquemia Encefálica/tratamento farmacológico , Hemorragia Cerebral/prevenção & controle , Fibrinolíticos/toxicidade , Fármacos Neuroprotetores/farmacologia , Ativador de Plasminogênio Tecidual/toxicidade , Aminopiridinas/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Modelos Animais de Doenças , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Microvasos/patologia , Distribuição Aleatória , Ratos Sprague-Dawley , Receptor A2B de Adenosina/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo
17.
Brain Behav Immun ; 61: 326-339, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28007523

RESUMO

Neuroinflammation is a major contributor to intracerebral hemorrhage (ICH) progression, but no drug is currently available to reduce this response and protect against ICH-induced injury. Recently, the natural product pinocembrin has been shown to ameliorate neuroinflammation and is undergoing a phase II clinical trial for ischemic stroke treatment. In this study, we examined the efficacy of pinocembrin in an ICH model, and further examined its effect on microglial activation and polarization. In vivo, pinocembrin dose-dependently reduced lesion volume by ∼47.5% and reduced neurologic deficits of mice at 72h after collagenase-induced ICH. The optimal dose of pinocembrin (5mg/kg) suppressed microglial activation as evidenced by decreases in CD68-positive microglia and reduced proinflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6. Pinocembrin also reduced the number of classically activated M1-like microglia without affecting M2-like microglia in the perilesional region. Additionally, pinocembrin decreased the expression of toll-like receptor (TLR)4 and its downstream target proteins TRIF and MyD88. The protection by pinocembrin was lost in microglia-depleted mice and in TLR4lps-del mice, and pinocembrin failed to decrease the number of M1-like microglia in TLR4lps-del mice. In lipopolysaccharide-stimulated BV-2 cells or primary microglia, pinocembrin decreased M1-related cytokines and markers (IL-1ß, IL-6, TNF-α, and iNOS), NF-κB activation, and TLR4 expression, but it did not interfere with TLR4/MyD88 and TLR4/TRIF interactions or affect microglial phagocytosis of red blood cells. Inhibition of the TLR4 signaling pathway and reduction in M1-like microglial polarization might be the major mechanism by which pinocembrin protects hemorrhagic brain. With anti-inflammatory properties, pinocembrin could be a promising new drug candidate for treating ICH and other acute brain injuries.


Assuntos
Anti-Inflamatórios/farmacologia , Flavanonas/farmacologia , Hemorragias Intracranianas/tratamento farmacológico , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Anti-Inflamatórios/uso terapêutico , Citocinas/metabolismo , Flavanonas/uso terapêutico , Hemorragias Intracranianas/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Fármacos Neuroprotetores/uso terapêutico
19.
J Nat Prod ; 80(5): 1684-1687, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28418245

RESUMO

Two new compounds, geranylpyrrol A (1) and piericidin F (2), were isolated from a reedsmycins nonproducing mutant strain of Streptomyces sp. CHQ-64. Their structures, including absolute configurations, were elucidated by extensive NMR, MS, NOESY, and ECD analyses. Geranylpyrrol A (1) is an unusual naturally occurring 2,3,4-trisubstituted pyrrole, and piericidin F (2) showed cytotoxicity against HeLa, NB4, A549, and H1975 cell lines with IC50 values of 0.003, 0.037, 0.56, and 0.49 µM, respectively.


Assuntos
Piridinas/isolamento & purificação , Piridinas/farmacologia , Pirróis/isolamento & purificação , Pirróis/farmacologia , Streptomyces/química , Linhagem Celular , Células HeLa , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Piridinas/química , Pirróis/química
20.
Postgrad Med J ; 93(1101): 406-413, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27941008

RESUMO

OBJECTIVE: Cardiac hypertrophy is the heart's response to a variety of extrinsic and intrinsic stimuli, some of which might finally lead up to a maladaptive state. Clinical evidence, in vitro and in vivo studies have implicated urotensin II (U-II/UTS2) in the development of cardiac hypertrophy, contributing to the (patho)-physiological regulation of cardiovascular homeostasis in humans. Several genes are associated with left ventricular hypertrophy; considering these, our objective was to evaluate the possible role of UTS2 gene polymorphisms (Thr21Met and Ser89Asn) in the genetic susceptibility to cardiac hypertrophy in a Chinese population. METHODS: A case-control study was designed to compare the distribution of alleles and genotypes between three groups: case group 1 (subjects with hypertension and cardiac hypertrophy, n=265), case group 2 (subjects with hypertension, without cardiac hypertrophy, n=768), and the control group (subjects neither with hypertension nor with cardiac hypertrophy, n=416). The detection of UTS2 gene polymorphisms was achieved with the PCR restriction fragment length polymorphism technique. RESULTS: We did not identify statistically significant differences between the three groups, neither with regard to the frequency of genotype/variant at the Ser89Asn locus nor at the Thr21Met locus. When stratified by sex, differences in genotype distribution of polymorphism Ser89Asn were only seen in female subjects in both the additive tested inheritance model (OR=0.507, 95% CI 0.249 to 1.032, p=0.032) and the recessive tested inheritance model (OR=0.475, 95% CI 0.239 to 0.945, p=0.034) between case group 2 (subjects with hypertension, without cardiac hypertrophy) and the control group (subjects neither with hypertension nor with cardiac hypertrophy). When stratified by sex, for female subjects with cardiac hypertrophy, we identified statistically significant differences in left ventricular posterior wall thickness for variant genotypes at the Ser89Asn locus (AA vs GG: 1.2500 (1.2000, 1.3750) vs 1.2500 (1.2000, 1.3750), p=0.03) and (AG+AA vs GG: 1.2000 (1.2000, 1.3000) vs 1.2000 (1.1000, 1.2000), p=0.01). CONCLUSIONS: Ser89Asn (S89N) polymorphisms of the UTS2 gene were associated with hypertension in a Chinese female population. Additionally, we demonstrated that genotype Asn89Asn was associated with left ventricular posterior wall thickness for subjects with hypertension and cardiac hypertrophy in a Chinese female population.


Assuntos
Cardiomegalia/genética , Hormônios Peptídicos/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Estudos de Casos e Controles , China , Feminino , Genótipo , Humanos , Hipertensão/genética , Peptídeos e Proteínas de Sinalização Intracelular , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores Sexuais
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