RESUMEN

The heart is a muscular organ that pumps blood throughout the body and is one of the most vital organs in human body. While cardiomyocytes are essential for maintaining the normal function of the heart, a variety of cardiovascular diseases such as coronary artery occlusion, arrhythmia, and myocarditis can lead to cardiomyocyte death, resulting in deterioration of heart function. The adult mammalian heart is incapable of regenerating sufficient cardiomyocytes following cardiac injuries, eventually leading to heart failure and death. Cardiac macrophages are ubiquitously distributed in the healthy heart and accumulated at the site of injury. Macrophages play essential roles in regulating homeostasis and proliferation of cardiomyocyte, promoting electrical conduction, and removing dead cardiomyocytes and debris through direct and indirect cell-cell crosstalk. In this review, we summarize the latest insights into the role of macrophages in maintaining cardiac homeostasis and the macrophage-cardiomyocyte crosstalk in both healthy and injured scenarios. Video Abstract.

Asunto(s)

Enfermedades Cardiovasculares , Insuficiencia Cardíaca , Adulto , Humanos , Animales , Miocitos Cardíacos , Homeostasis , Macrófagos , Mamíferos

RESUMEN

Indoleamine 2,3-dioxygenase 1 (IDO1) is a heme enzyme involved in catalyzing the conversion of tryptophan (Trp) into kynurenine (Kyn) at the first rate-limiting step in the kynurenine pathway of L-tryptophan metabolism. It has been found to be involved in several biological functions such as aging, immune microorganism, neurodegenerative and infectious diseases, and cancer. IDO1 plays an important role in immune tolerance by depleting tryptophan in the tumor microenvironment and inhibiting the proliferation of effector T cells, which makes it an important emerging biomarker for cancer immunotherapy. Therefore, the research and development of IDO1 inhibitors are of great importance for tumor therapy. Of interest, IDO activity assays are of great value in the screening and evaluation of inhibitors. Herein, we mainly review the biological functions of IDO1, immune regulation, key signaling molecules in the response pathway, and the development of IDO1 inhibitors in clinical trials. Furthermore, this review provides a comprehensive overview and, in particular, a discussion of currently available IDO activity assays for use in the evaluation of IDO inhibitors in human blood. We believe that the IDO activity is a promising biomarker for the immune escape and laboratory evaluation of tumor immunotherapy.

RESUMEN

Purpose: Resistance training (RT) can intervene in aging, which can effectively improve trainees' life. However, unhealthy living habits such as irregular life, obesity and hyperlipidemia, and chronic diseases lead to a significant decline in the energy level of the population, seriously affecting the health of the population. Our research identifies the research hotspots of RT to intervene in aging from the perspective of bibliometrics, predicts research frontiers and development trends, and provides more perspectives for research on aging populations. Methods: In this study, we used CiteSpace and VOSviewer visualization software to draw the scientific knowledge map of countries/regions, institutions, authors, co-occurrence keywords, and co-cited references of published articles, and explore the Web of Science core collection database all about the RT intervention aging research status, hotspots, frontiers, and development trends of articles on aging. Results: Among the 760 articles that meet the inclusion criteria, the number of articles published and the frequency of citations have increased steadily in the past 5 years. Judging from the countries/regions, institutions, scholars, and journals that published articles, the ones with the largest numbers are the USA, Univ Estadual Londrina, Cyrino ES, and Exp Gerontol. The ones with the highest influence are England, Univ Arkansas Med Sci, Frontera WR, and Biochem Biophys Rep Co. The top five co-occurrence keywords of include exercise, strength, resistance training, skeletal muscle, and muscle strength. The research frontier is physical function. Conclusion: In the field of RT intervention aging research, relevant scholars deserve further in-depth research and exploration. The United States, Brazil, Canada, and other economically developed countries/regions, institutions, and authors have greater influence and productivity. These quantitative research results can provide references for relevant scholars' follow-up research and government departments to formulate and modify health policies or measures.

Asunto(s)

Entrenamiento de Fuerza , Humanos , Bibliometría , Envejecimiento , Brasil , Canadá

RESUMEN

Pulmonary fibrosis is a typical sequela of coronavirus disease 2019 (COVID-19), which is linked with a poor prognosis for COVID-19 patients. However, the underlying mechanism of pulmonary fibrosis induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unclear. Here, we demonstrated that the nucleocapsid (N) protein of SARS-CoV-2 induced pulmonary fibrosis by activating pulmonary fibroblasts. N protein interacted with the transforming growth factor ß receptor I (TßRI), to disrupt the interaction of TßRI-FK506 Binding Protein12 (FKBP12), which led to activation of TßRI to phosphorylate Smad3 and boost expression of pro-fibrotic genes and secretion of cytokines to promote pulmonary fibrosis. Furthermore, we identified a compound, RMY-205, that bound to Smad3 to disrupt TßRI-induced Smad3 activation. The therapeutic potential of RMY-205 was strengthened in mouse models of N protein-induced pulmonary fibrosis. This study highlights a signaling pathway of pulmonary fibrosis induced by N protein and demonstrates a novel therapeutic strategy for treating pulmonary fibrosis by a compound targeting Smad3.

Asunto(s)

COVID-19 , Fibrosis Pulmonar , Animales , Ratones , COVID-19/complicaciones , Fibrosis , Proteínas de la Nucleocápside/uso terapéutico , Fibrosis Pulmonar/complicaciones , Fibrosis Pulmonar/tratamiento farmacológico , SARS-CoV-2

RESUMEN

Disrupted neonatal lung angiogenesis and alveologenesis often give rise to bronchopulmonary dysplasia (BPD), the most common chronic lung disease in children. Hyperoxia-induced pulmonary vascular and alveolar damage in premature infants is one of the most common and frequent factors contributing to BPD. The purpose of the present study was to explore the key molecules and the underlying mechanisms in hyperoxia-induced lung injury in neonatal mice and to provide a new strategy for the treatment of BPD. In this work, we reported that hyperoxia decreased the proportion of endothelial cells (ECs) in the lungs of neonatal mice. In hyperoxic lung ECs of neonatal mice, we detected upregulated fibroblast growth factor receptor 1 (FGFR1) expression, accompanied by upregulation of the classic downstream signaling pathway of activated FGFR1, including the ERK/MAPK signaling pathway and PI3K-Akt signaling pathway. Specific deletion of Fgfr1 in the ECs of neonatal mice protected the lungs from hyperoxia-induced lung injury, with improved angiogenesis, alveologenesis and respiratory metrics. Intriguingly, the increased Fgfr1 expression was mainly attributed to aerosol capillary endothelial (aCap) cells rather than general capillary endothelial (gCap) cells. Deletion of endothelial Fgfr1 increased the expression of gCap cell markers but decreased the expression of aCap cell markers. Additionally, inhibition of FGFR1 by an FGFR1 inhibitor improved alveologenesis and respiratory metrics. In summary, this study suggests that in neonatal mice, hyperoxia increases the expression of endothelial FGFR1 in lung ECs and that deficiency of endothelial Fgfr1 can ameliorate hyperoxia-induced BPD. These data suggest that FGFR1 may be a potential therapeutic target for BPD, which will provide a new strategy for the prevention and treatment of BPD.

RESUMEN

Epithelial-mesenchymal transition (EMT) has fundamental roles in various biological processes. However, there are still questions pending in this fast-moving field. Here we report that in TGFß-induced EMT, ERK-mediated Smurf1 phosphorylation is a prerequisite step for RhoA degradation and the consequent mesenchymal state achievement. Upon TGFß treatment, activated ERK phosphorylates Thr223 of Smurf1, a member of HECT family E3 ligase, to promote Smurf1-mediated polyubiquitination and degradation of RhoA, thereby leading to cell skeleton rearrangement and EMT. Blockade of phosphorylation of Smurf1 inhibits TGFß-induced EMT, and accordingly, dramatically blocks lung metastasis of murine breast cancer in mice. Hence, our study reveals an unknown role of ERK in TGFß-induced EMT and points out a potential strategy in therapeutic intervention.

Asunto(s)

Fenómenos Biológicos , Neoplasias , Animales , Transición Epitelial-Mesenquimal , Ratones , Factor de Crecimiento Transformador beta/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo

RESUMEN

Extraction of chitin from crustacean waste with acidic natural deep eutectic solvents (NADESs) is usually accompanied by degradation of chitin, which lowers the yield and molecular weight of product. Herein, this study proposed a eco-friendly and feasible route for effectively improving the yield and molecular weight of chitin by introducing N-acetyl-D-glucosamine into ternary NADESs. A high molecular weight chitin with molecular weight of 3.92 × 105 Da, purity of 90.2% and yield of 85.6% was obtained from crab shell. Compared with conventional acid/alkali and binary NADESs method, the maximum yield of chitin extracted by ChCl-G-FA2 was increased by 1.57 times and 1.39 times respectively. Molecular weight of chitin was 3.16 times that of acid/alkali method. Recycling performance evaluation revealed that the purity of chitin could still reach 80.4% after five cycles of NADESs. This study provided a eco-friendly utilization strategy for crustacean waste based on multifunctional NADESs.

Asunto(s)

Quitina , Disolventes Eutécticos Profundos , Animales , Crustáceos , Solventes

RESUMEN

OBJECTIVES: To present a review on the traditional and new biomarkers of pulmonary embolism (PE). DATA SOURCE: A systematic search has been carried out using keywords as PE, biomarker, diagnosis and risk stratification. RESULTS: The results of this work have been structured into three parts: first, conventional biomarkers for vascular, cardiac and inflammation, including static markers and dynamic markers for measuring the time course; next, a review of new biomarkers in recent years, such as RNAs and markers obtained through proteomics and mass spectrometry; finally, use of new detection methods to directly detect the activity of existing markers, such as the determination of coagulation factor II and plasmin activities based on the proteolytic activation of an engineered zymogen. CONCLUSIONS: This work summarized the characteristics of current traditional biomarkers for clinical diagnosis and risk stratification of PE, as well as a series of newly discovered biomarkers obtained through various clinical experimental methods.

Asunto(s)

Embolia Pulmonar , Biomarcadores , Humanos , Espectrometría de Masas , Proteómica , Embolia Pulmonar/diagnóstico , Medición de Riesgo

RESUMEN

BACKGROUND: Thymosin ß4 (Tß4) is the most abundant member of the ß-thymosins and plays an important role in the control of actin polymerization in eukaryotic cells. While its effects in multiple organs and diseases are being widely investigated, the safety profile has been established in animals and humans, currently, little is known about its influence on Alzheimer's disease (AD) and the possible mechanisms. Thus, we aimed to evaluate the effects and mechanisms of Tß4 on glial polarization and cognitive performance in APP/PS1 transgenic mice. METHODS: Behavior tests were conducted to assess the learning and memory, anxiety and depression in APP/PS1 mice. Thioflavin S staining, Nissl staining, immunohistochemistry/immunofluorescence, ELISA, qRT-PCR, and immunoblotting were performed to explore Aß accumulation, phenotypic polarization of glial cells, neuronal loss and function, and TLR4/NF-κB axis in APP/PS1 mice. RESULTS: We demonstrated that Tß4 protein level elevated in all APP/PS1 mice. Over-expression of Tß4 alone alleviated AD-like phenotypes of APP/PS1 mice, showed less brain Aß accumulation and more Insulin-degrading enzyme (IDE), reversed phenotypic polarization of microglia and astrocyte to a healthy state, improved neuronal function and cognitive behavior performance, and accidentally displayed antidepressant-like effect. Besides, Tß4 could downregulate both TLR4/MyD88/NF-κB p65 and p52-dependent inflammatory pathways in the APP/PS1 mice. While combination drug of TLR4 antagonist TAK242 or NF-κB p65 inhibitor PDTC exerted no further effects. CONCLUSIONS: These results suggest that Tß4 may exert its function by regulating both classical and non-canonical NF-κB signaling and is restoring its function as a potential therapeutic target against AD.

Asunto(s)

Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Disfunción Cognitiva/metabolismo , FN-kappa B/metabolismo , Neuroglía/metabolismo , Timosina/genética , Timosina/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Astrocitos/metabolismo , Modelos Animales de Enfermedad , Femenino , Masculino , Memoria , Ratones , Ratones Transgénicos , Microglía/metabolismo , Neuronas/metabolismo , Fenotipo , Presenilina-1/genética , Transducción de Señal

RESUMEN

INTRODUCTION: Recent animal studies showed that isoflurane exposure may lead to the disturbance of hippocampal neurogenesis and later cognitive impairment. However, much less is known about the effect of isoflurane exposure on the neurons generated form tertiary dentate matrix, even though a great increase of granule cell population during the infantile period is principally derived from this area. METHODS: To label the new cells originated from the tertiary dentate matrix, the mice were injected with BrdU on postnatal day 6 (P6). Then, the mice were exposed to isoflurane for 4 hr at 1, 8, 21, and 42 days after BrdU injection, and the brains were collected 24 hr later. The loss of newly generated cells/neurons with different developmental stage was assessed by BrdU, BrdU + DCX, BrdU + NeuN, or BrdU + Prox-1 staining, respectively. RESULTS: We found that the isoflurane exposure significantly decreased the numbers of nascent cells (1 day old) and mature neurons (42 days old), but had no effect on the immature (8 days old) and early mature neurons (8 and 21 days old, respectively). CONCLUSION: The results suggested isoflurane exposure exerts the neurotoxic effects on the tertiary dentate matrix-originated cells with an age-defined pattern in mice, which partly explain the cognitive impairment resulting from isoflurane exposure to the young brain.

Asunto(s)

Isoflurano , Animales , Proliferación Celular , Giro Dentado , Proteína Doblecortina , Hipocampo , Isoflurano/toxicidad , Ratones , Neurogénesis , Neuronas

RESUMEN

In animal models with temporal lobe epilepsy (TLE), the status epilepticus (SE) leads to a dramatic increase in number of newly born neuron in the subgranular zone (SGZ) of dentate gyrus. How the SE confers a modulation in the dentate neurogenesis is mostly unknown. Gadd45b is involved in epigenetic gene activation by DNA demethylation. This study was performed to present a novel mechanism underling SE-induced dentate neurogenesis. A transient induction (12 hrs to 3 days) of Gadd45b was observed in dentate gyrus of mice after pilocarpine-induced SE. Labeling the dividing cells with BrdU, we next found that the induction of Gadd45b was required to increase the rate of cell proliferation in the dentate gyrus at 7 and 14 days after SE. Afterward, the DNA methylation levels for candidate growth factor genes critical for the adult neurogenesis were assayed with Sequenom MassARRAY Analyzer. The results indicated that Gadd45b was necessary for SE-induced DNA demethylation of specific promoters and expression of corresponding genes in the dentate gyrus, including brain-derived neurotrophic factor (BDNF) and fibroblast growth factor-2 (FGF-2). Using Timm staining, we further suggested that SE-induced Gadd45b might contribute to the subsequent mossy fiber sprouting (MFS) in the chronically epileptic hippocampus via epigenetic regulation of dentate neurogenesis at early stage after SE. Together, Gadd45b links pilocarpine-induced SE to epigenetic DNA modification of secreted factors in the dentate gyrus, leading to extrinsic modulation on the neurogenesis.

Asunto(s)

Giro Dentado , Estado Epiléptico , Animales , Antígenos de Diferenciación , Epigénesis Genética , Hipocampo , Ratones , Neurogénesis , Pilocarpina/toxicidad , Estado Epiléptico/inducido químicamente , Estado Epiléptico/genética

RESUMEN

Nuclear receptor Nur77 participates in multiple metabolic regulations and plays paradoxical roles in tumorigeneses. Herein, we demonstrated that the knockout of Nur77 stimulated mammary tumor development in two mouse models, which would be reversed by a specific reexpression of Nur77 in mammary tissues. Mechanistically, Nur77 interacted and recruited corepressors, the SWI/SNF complex, to the promoters of CD36 and FABP4 to suppress their transcriptions, which hampered the fatty acid uptake, leading to the inhibition of cell proliferation. Peroxisome proliferator-activated receptor-γ (PPARγ) played an antagonistic role in this process through binding to Nur77 to facilitate ubiquitin ligase Trim13-mediated ubiquitination and degradation of Nur77. Cocrystallographic and functional analysis revealed that Csn-B, a Nur77-targeting compound, promoted the formation of Nur77 homodimer to prevent PPARγ binding by steric hindrance, thereby strengthening the Nur77's inhibitory role in breast cancer. Therefore, our study reveals a regulatory function of Nur77 in breast cancer via impeding fatty acid uptake.

Asunto(s)

Neoplasias de la Mama/patología , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , PPAR gamma/metabolismo , Fenilacetatos/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Proliferación Celular , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Ácidos Grasos/metabolismo , Femenino , Humanos , Estimación de Kaplan-Meier , Metabolismo de los Lípidos/efectos de los fármacos , Glándulas Mamarias Animales/patología , Ratones , Persona de Mediana Edad , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/agonistas , PPAR gamma/agonistas , Cultivo Primario de Células , Pronóstico , Proteolisis/efectos de los fármacos , Análisis de Matrices Tisulares , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/metabolismo , Ubiquitinación/efectos de los fármacos

RESUMEN

Zinc finger protein 804A (ZNF804A) has been identified by genome­wide association studies as a robust risk gene in schizophrenia, but how ZNF804A contributes to schizophrenia and its upstream regulation remains unknown. Previous studies have indicated that microRNAs (miRs) are key factors that regulate the expression levels of their target genes. The present study revealed significantly increased expression of miR­148b­3p in the peripheral blood of patients with first­onset schizophrenia compared with healthy controls, and bioinformatics analysis predicted that the ZNF804A gene is a target of miR­148b­3p. Therefore, the present study investigated the possible upstream regulation of ZNF804A by miR­148b­3p in the human neuroblastoma SH­SY5Y cell line, and assessed the implications for schizophrenia. The results revealed significantly reversed expression levels of miR­148b­3p (P=0.0051) and ZNF804A (P=0.0218) in the peripheral blood of patients with first­onset schizophrenia compared with healthy individuals. Furthermore, it was demonstrated that miR­148b­3p directly targeted ZNF804A via binding to conserved target sites in the 3'­untranslated region of ZNF804A mRNA, where it inhibited the endogenous expression of ZNF804A at both the mRNA (P=0.048) and protein levels (P=0.013) in SH­SY5Y cells. Furthermore, miR­148b­3p was revealed to regulate the expression levels of catechol­O­methyltransferase (COMT) and serine protease 16 (PRSS16) by targeting ZNF804A in SH­SY5Y cells. Collectively, the present results indicated that there was a direct upstream regulation of the schizophrenia risk gene ZNF804A by miR­148b­3p, which contributed to the regulation of the downstream genes COMT and PRSS16. Thus, the miR­148b­3p/ZNF804A/COMT/PRSS16 pathway may play an important role in the pathophysiology of schizophrenia, and may serve as a potential target in drug discovery and gene therapy for this disorder.

Asunto(s)

Catecol O-Metiltransferasa/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , MicroARNs/metabolismo , Esquizofrenia/metabolismo , Serina Endopeptidasas/metabolismo , Estudios de Casos y Controles , Línea Celular Tumoral , Regulación de la Expresión Génica , Humanos , Factores de Transcripción de Tipo Kruppel/sangre , MicroARNs/sangre

RESUMEN

The solubility range of interstitial Ni in the ZrNi1+x Sn half-Heusler phase is a controversial issue, but it has an impact on the thermoelectric properties. In this study, two isothermal section phase diagrams of the Zr-Ni-Sn ternary system at 973 K and 1173 K were experimentally constructed based on the binary phase diagrams of Zr-Ni, Zr-Sn, and Ni-Sn. The thermodynamic equilibrium phases were obtained after a long time of heating treatment on the raw alloys prepared by levitation melting. Solubilities of x < 0.07 at 973 K and x < 0.13 at 1173 K were clearly indicated. An intermediate-Heusler phase with a partly filled Ni void was observed, which is believed to be beneficial to the lowered lattice thermal conductivity. The highest ZT value~0.71 at 973 K was obtained for ZrNi1.11Sn1.04. The phase boundary mapping provides an important instruction for the further optimization of ZrNiSn-based materials and other systems.

RESUMEN

Increased number of newly-born neurons produced at latent stage after status epilepticus (SE) contribute to aberrant rewiring of hippocampus and are hypothesized to promote epileptogenesis. Although physical training (PT) was reported to cause further increase in neurogenesis after SE, how PT affect their integration pattern is still elusive, whether they integrate into normal circuits or increase aberrant integrations is yet to be determined. To understand this basic mechanism by which PT effects SE and to elaborate the possible role of neuronal integrations in prognosis of SE, we evaluated the effect of 4 weeks of treadmill PT in adult male mice after pilocarpine-induced SE on behavioral and aberrant integrations' parameters. Changes in BDNF gene methylation and its protein level in hippocampus was also measured at latent stage (2-weeks) to explore underlying pathways involved in increasing neurogenesis. Our results demonstrated that although PT increased proliferation and maturation of neurons in dentate gyrus, they showed reduced aberrant integrations into hippocampal circuitry assessed through a decrease in the number of ectopic granular cells, hilar basal dendrites and mossy fiber sprouting as compared to non-exercised SE mice. While SE decreased the percentage methylation of specific CpGs of BDNF gene's promoter, PT did not yield any significant difference in methylation of BDNF CpGs as compared to non-exercised SE mice. In conclusion, PT increases hippocampal neurogenesis through increasing BDNF levels by some pathways other than demethylating BDNF CpGs and causes post SE newly-born neurons to integrate into normal circuits thus resulting in decreased spontaneous recurrent seizures and enhanced spatial memory.

Asunto(s)

Giro Dentado/metabolismo , Hipocampo/metabolismo , Neurogénesis/fisiología , Condicionamiento Físico Animal , Estado Epiléptico/terapia , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Proliferación Celular/fisiología , Islas de CpG , ADN/metabolismo , Metilación de ADN , Giro Dentado/patología , Hipocampo/patología , Masculino , Ratones , Neuronas/metabolismo , Neuronas/patología , Pilocarpina , Estado Epiléptico/inducido químicamente , Estado Epiléptico/metabolismo , Regulación hacia Arriba

RESUMEN

Tripartite motif 32 (TRIM32) is a member of TRIM family that plays a potential role in neural regeneration. However, the biological function of TRIM32 in cerebral ischemia reperfusion injury has not been investigated. In the present study, we evaluated the expression level of TRIM32 in hippocampal neurons following oxygen-glucose deprivation/reperfusion (OGD/R). The results showed that TRIM32 expression was significantly elevated in hippocampal neurons subjected to OGD/R as compared to the neurons cultured in the normoxia condition. To further evaluate the role of TRIM32, hippocampal neurons were transfected with TRIM32 small interfering RNA (si-TRIM32) to knock down TRIM32. We found that knockdown of TRIM32 improved cell viability of OGD/R-stimulated hippocampal neurons. Generation of reactive oxygen species was decreased, while contents of superoxide dismutase and glutathione peroxidase were increased after si-TRIM32 transfection. Knockdown of TRIM32 suppressed cell apoptosis, as proved by the increased bcl-2 expression along with decreased bax expression and caspase-3 activity. We also found that TRIM32 knockdown enhanced OGD/R-induced activation of Nrf2 signaling pathway in hippocampal neurons. Furthermore, siRNA-Nrf2 was transfected to knock down Nrf2. SiRNA-Nrf2 transfection reversed the protective effects of TRIM32 knockdown on neurons. These data suggested that knockdown of TRIM32 protected hippocampal neurons from OGD/R-induced oxidative injury through activating Nrf2 signaling pathway.

Asunto(s)

Hipocampo/metabolismo , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Factores de Transcripción/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Apoptosis/fisiología , Femenino , Técnicas de Silenciamiento del Gen , Glucosa/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuroprotección/fisiología , Oxígeno/metabolismo , Embarazo , Ratas Wistar , Daño por Reperfusión/metabolismo , Transducción de Señal/fisiología , Factores de Transcripción/genética , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética

RESUMEN

BACKGROUNDS: Metabotropic glutamate receptors, besides ionotropic receptors, mediate the complicated effect of glutamate on neurogenesis. Previous studies showed that metabotropic glutamate receptor 4 (mGluR4) regulated the proliferation and differentiation of neural stem/progenitor cells in vitro. However, little is known about the expression pattern of mGluR4 on prenatal central nervous system in vivo, especially the human being. METHODS: The normal brain tissues of human fetus were collected and divided into 4 groups according to the gestational age: 9-11 W, 14-16 W, 22-24 W and 32-36 W. Then the expression of mGluR4 was evaluated at mRNA and protein levels by means of PCR or immunohistochemistry method, respectively. The type of cell expressing mGluR4 was further investigated using double-labeling immunofluorescence. RESULTS: RT-PCR showed that the mRNA of mGluR4 could be detected in frontal lobe from 9 W to 32 W and real-time PCR quantificationally demonstrated the mRNA increased with development. Similarly, immnoreactivity was found in all layers of frontal lobe, VZ/SVZ. The intensity scores analysis showed that the staining became stronger and the range extended gradually with development. The double-labeling immunofluorescence showed that mGluR4 was present in neural stem/progenitor cells (nestin-positive cells after 9 W), young neurons (DCX-positive cells after 9 W), mature neurons (NeuN-positive cells in cortex after 32 W), as well as typical astrocytes (GFAP-positive cells in medulla after 32 W). CONCLUSION: These results supply an important evidence that mGluR4 is expressed in prenatal human cerebrum, and main kinds of cells related to neurogenesis are involved in its expression.

Asunto(s)

Encéfalo/embriología , Lóbulo Frontal/embriología , Receptores de Glutamato Metabotrópico/metabolismo , Encéfalo/metabolismo , Diferenciación Celular/fisiología , Sistema Nervioso Central/citología , Sistema Nervioso Central/embriología , Sistema Nervioso Central/metabolismo , Corteza Cerebral/citología , Corteza Cerebral/embriología , Corteza Cerebral/metabolismo , Femenino , Desarrollo Fetal/genética , Lóbulo Frontal/citología , Lóbulo Frontal/metabolismo , Ácido Glutámico/metabolismo , Humanos , Inmunohistoquímica , Masculino , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Neurogénesis/fisiología , Neuronas/metabolismo , Embarazo , Receptores de Glutamato Metabotrópico/genética

RESUMEN

The development of chronically implanted electrodes attracts much attention since these electrodes are much favorable for monitoring changes of neurotransmitters in brain science. The research in this field focused mainly on chemical modification to improve the potential stability and less on the biocompatibility. In this work, for the first time, we proposed the concept of cell-membrane electrodes based on a basic hypothesis using animal's self-cell membrane to reduce animal exclusiveness (hyperacute rejection and chronic rejection). As a proof of concept, we first studied cell-membrane reference electrodes for chronically implanted electrodes. Red cell membrane (RCM) was extracted from rat blood and coated on the chemically modified Ag/AgCl electrodes. It was found that ionic liquid (IL) 1-butyl-2,3-dimethylimidazolium hexafluorophosphate (BDMI) showed good performance rather than Nafion used as coating film for protection of silver chloride on Ag wire and support of the cell membrane. Electrochemical impedance spectra supported that charge-transfer resistance nearly kept constant before and after the electrodes were implanted into the rat's brain tissues for 28 days. Immunohistochemical analysis of the implant sites in the rat's brain tissues indicated that the extent of glial scarring arising from the Ag/AgCl/BDMI/RCM electrodes was smaller than that of both Ag/AgCl/Nafion and Ag/AgCl/Nafion/RCM electrodes after 28 days of implantation. The RCM-coated Ag/AgCl/IL electrodes showed a relatively potential stability compared to RCM-noncoated Ag/AgCl/IL electrodes after 28 days of implantation. Additionally, the current-voltage curve demonstrated that the RCM-coated electrodes can be used as polarized electrodes. This work demonstrated that the RCM, which was coated on the Ag/AgCl/IL electrodes, can significantly improve the biocompatibility and potential stability of the RCM-noncoated Ag/AgCl/IL electrodes implanted in the rat brain. The cell-membrane-coated electrodes will serve as a lighthouse in guiding the design of chronically implanted electrodes for in vivo electrochemical detection.

Asunto(s)

Materiales Biocompatibles/química , Encéfalo/fisiología , Animales , Astrocitos/metabolismo , Astrocitos/patología , Encéfalo/metabolismo , Encéfalo/patología , Membrana Celular/química , Espectroscopía Dieléctrica , Electrodos Implantados , Polímeros de Fluorocarbono/química , Proteína Ácida Fibrilar de la Glía/metabolismo , Líquidos Iónicos/química , Masculino , Ratas , Plata/química , Compuestos de Plata/química

RESUMEN

BACKGROUND: MicroRNAs play crucial roles in tumorigenesis and tumor progression. miR-770 has been reported to be downregulated in several cancers and affects cancer cell proliferation, apoptosis, metastasis and drug resistance. However, the role and underlying molecular mechanism of miR-770 in human glioma remain unknown and need to be further elucidated. METHODS: The expression of miR-770 in glioma tissues and cell lines was measured by quantitative real-time PCR (qRT-PCR) to explore the association of miR-770 expression with clinicopathological characteristics. The expression of CDK8 was detected by qRT-PCR and Western blotting in glioma tissues. A target prediction program and a dual-luciferase reporter assay were used to confirm that CDK8 is a target gene of miR-770. MTT and cell counting assays were used to assess the effect of miR-770 on glioma cell proliferation. The cell cycle distribution and apoptosis were examined by flow cytometry. CDK8 siRNA and overexpression were used to further confirm the function of the target gene. RESULTS: We demonstrated that miR-770 expression was downregulated in human glioma tissues and cell lines. The overexpression of miR-770 inhibited glioma cell proliferation and cell cycle G1-S transition and induced apoptosis. The inhibition of miR-770 facilitated cell proliferation and G1-S transition and suppressed apoptosis. miR-770 expression was inversely correlated with CDK8 expression in glioma tissues. CDK8 was confirmed to be a direct target of miR-770 by using a luciferase reporter assay. The overexpression of miR-770 decreased CDK8 expression at both the mRNA and protein levels, and the suppression of miR-770 increased CDK8 expression. Importantly, CDK8 silencing recapitulated the cellular and molecular effects observed upon miR-770 overexpression, and CDK8 overexpression eliminated the effects of miR-770 overexpression on glioma cells. Moreover, both exogenous expression of miR-770 and silencing of CDK8 resulted in suppression of the Wnt/ß-catenin signaling pathway. CONCLUSIONS: Our study demonstrates that miR-770 inhibits glioma cell proliferation and G1-S transition and induces apoptosis through suppression of the Wnt/ß-catenin signaling pathway by targeting CDK8. These findings suggest that miR-770 plays a significant role in glioma progression and serves as a potential therapeutic target for glioma.

RESUMEN

p62 is a receptor that facilitates selective autophagy by interacting simultaneously with cargoes and LC3 protein on the autophagosome to maintain cellular homeostasis. However, the regulatory mechanism(s) behind this process and its association with breast cancer remain to be elucidated. Here, we report that Flightless-I (FliI), a novel p62-interacting protein, promotes breast cancer progression by impeding selective autophagy. FliI was highly expressed in clinical breast cancer samples, and heterozygous deletion of FliI retarded the development of mammary tumors in PyVT mice. FliI induced p62-recruited cargoes into Triton X-100 insoluble fractions (TI) to form aggregates, thereby blocking p62 recognition of LC3 and hindering p62-dependent selective autophagy. This function of Flil was reinforced by Akt-mediated phosphorylation at Ser436 and inhibited by phosphorylation of Ulk1 at Ser64. Obstruction of autophagic clearance of p62-recruited cargoes by FliI was associated with the accumulation of oxidative damage on proteins and DNA, which could contribute to the development of cancer. Heterozygous knockout of FliI facilitated selectively autophagic clearance of aggregates, abatement of ROS levels, and protein oxidative damage, ultimately retarding mammary cancer progression. In clinical breast cancer samples, Akt-mediated phosphorylation of FliI at Ser436 negatively correlated with long-term prognosis, while Ulk1-induced FliI phosphorylation at Ser64 positively correlated with clinical outcome. Together, this work demonstrates that FliI functions as a checkpoint protein for selective autophagy in the crosstalk between FliI and p62-recruited cargoes, and its phosphorylation may serve as a prognostic marker for breast cancer.Significance: Flightless-I functions as a checkpoint protein for selective autophagy by interacting with p62 to block its recognition of LC3, leading to tumorigenesis in breast cancer.Cancer Res; 78(17); 4853-64. ©2018 AACR.

Asunto(s)

Neoplasias de la Mama/genética , Carcinogénesis/genética , Proteínas de Microfilamentos/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas de Unión al ARN/genética , Receptores Citoplasmáticos y Nucleares/genética , Adulto , Anciano , Animales , Autofagosomas/metabolismo , Autofagosomas/patología , Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Mama/metabolismo , Mama/patología , Neoplasias de la Mama/patología , Progresión de la Enfermedad , Femenino , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Persona de Mediana Edad , Fosforilación , Unión Proteica/genética , Transactivadores