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1.
Biosens Bioelectron ; 258: 116298, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38701537

RESUMO

Wireless activation of the enteric nervous system (ENS) in freely moving animals with implantable optogenetic devices offers a unique and exciting opportunity to selectively control gastrointestinal (GI) transit in vivo, including the gut-brain axis. Programmed delivery of light to targeted locations in the GI-tract, however, poses many challenges not encountered within the central nervous system (CNS). We report here the development of a fully implantable, battery-free wireless device specifically designed for optogenetic control of the GI-tract, capable of generating sufficient light over large areas to robustly activate the ENS, potently inducing colonic motility ex vivo and increased propulsion in vivo. Use in in vivo studies reveals unique stimulation patterns that increase expulsion of colonic content, likely mediated in part by activation of an extrinsic brain-gut motor pathway, via pelvic nerves. This technology overcomes major limitations of conventional wireless optogenetic hardware designed for the CNS, providing targeted control of specific neurochemical classes of neurons in the ENS and brain-gut axis, for direct modulation of GI-transit and associated behaviours in freely moving animals.


Assuntos
Sistema Nervoso Entérico , Optogenética , Tecnologia sem Fio , Animais , Optogenética/instrumentação , Sistema Nervoso Entérico/fisiologia , Camundongos , Tecnologia sem Fio/instrumentação , Eixo Encéfalo-Intestino/fisiologia , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Encéfalo/fisiologia , Camundongos Endogâmicos C57BL
3.
Opt Express ; 31(12): 20505-20517, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381444

RESUMO

A true-color light-field display system with a large depth-of-field (DOF) is demonstrated. Reducing crosstalk between viewpoints and increasing viewpoint density are the key points to realize light-field display system with large DOF. The aliasing and crosstalk of light beams in the light control unit (LCU) are reduced by adopting collimated backlight and reversely placing the aspheric cylindrical lens array (ACLA). The one-dimensional (1D) light-field encoding of halftone images increases the number of controllable beams within the LCU and improves viewpoint density. The use of 1D light-field encoding leads to a decrease in the color-depth of the light-field display system. The joint modulation for size and arrangement of halftone dots (JMSAHD) is used to increase color-depth. In the experiment, a three-dimensional (3D) model was constructed using halftone images generated by JMSAHD, and a light-field display system with a viewpoint density of 1.45 (i.e. 1.45 viewpoints per degree of view) and a DOF of 50 cm was achieved at a 100 ° viewing angle.

4.
Nat Commun ; 14(1): 1259, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36878953

RESUMO

It is widely thought that Wnt/Lrp6 signaling proceeds through the cytoplasm and that motile cilia are signaling-inert nanomotors. Contrasting both views, we here show in the mucociliary epidermis of X. tropicalis embryos that motile cilia transduce a ciliary Wnt signal that is distinct from canonical ß-catenin signaling. Instead, it engages a Wnt-Gsk3-Ppp1r11-Pp1 signaling axis. Mucociliary Wnt signaling is essential for ciliogenesis and it engages Lrp6 co-receptors that localize to cilia via a VxP ciliary targeting sequence. Live-cell imaging using a ciliary Gsk3 biosensor reveals an immediate response of motile cilia to Wnt ligand. Wnt treatment stimulates ciliary beating in X. tropicalis embryos and primary human airway mucociliary epithelia. Moreover, Wnt treatment improves ciliary function in X. tropicalis ciliopathy models of male infertility and primary ciliary dyskinesia (ccdc108, gas2l2). We conclude that X. tropicalis motile cilia are Wnt signaling organelles that transduce a distinct Wnt-Pp1 response.


Assuntos
Ciliopatias , Via de Sinalização Wnt , Humanos , Masculino , Cílios , Quinase 3 da Glicogênio Sintase , Ciliopatias/genética , Citoplasma , Proteínas dos Microfilamentos , Proteínas Associadas aos Microtúbulos
5.
Dev Cell ; 58(2): 139-154.e8, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36693320

RESUMO

WNT signaling is important in development, stem cell maintenance, and disease. WNT ligands typically signal via receptor activation across the plasma membrane to induce ß-catenin-dependent gene activation. Here, we show that in mammalian primary cilia, WNT receptors relay a WNT/GSK3 signal that ß-catenin-independently promotes ciliogenesis. Characterization of a LRP6 ciliary targeting sequence and monitoring of acute WNT co-receptor activation (phospho-LRP6) support this conclusion. Ciliary WNT signaling inhibits protein phosphatase 1 (PP1) activity, a negative regulator of ciliogenesis, by preventing GSK3-mediated phosphorylation of the PP1 regulatory inhibitor subunit PPP1R2. Concordantly, deficiency of WNT/GSK3 signaling by depletion of cyclin Y and cyclin-Y-like protein 1 induces primary cilia defects in mouse embryonic neuronal precursors, kidney proximal tubules, and adult mice preadipocytes.


Assuntos
Proteínas Wnt , beta Catenina , Animais , Camundongos , beta Catenina/metabolismo , Proteínas Wnt/metabolismo , Cílios/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Via de Sinalização Wnt , Fosforilação , Ciclinas/metabolismo , Mamíferos/metabolismo
6.
Molecules ; 27(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36431989

RESUMO

For ultra-deep desulfurization of diesel fuel, this study applied the ultrasound-assisted catalytic ozonation process to the dibenzothiophene (DBT) removal process with four Keggin-type heteropolyacids (HPA) as catalysts and acetonitrile as extractant. Through experimental evaluations, H3PMo12O40 was found to be the most effective catalyst for the oxidative removal of DBT. Under favorable operating conditions with a temperature of 0 °C, H3PMo12O40 dosage of 2.5 wt.% of n-octane, and ultrasonic irradiation, DBT can be effectively removed from simulated diesel. Moreover, the reused catalyst exhibited good catalytic activity in recovery experiments. This desulfurization process has high potential for ultra-deep desulfurization of diesel.


Assuntos
Ozônio , Ultrassom , Oxirredução , Catálise , Gasolina
7.
EMBO Mol Med ; 14(4): e14990, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35253392

RESUMO

The heterogeneous response of acute myeloid leukemia (AML) to current anti-leukemic therapies is only partially explained by mutational heterogeneity. We previously identified GPR56 as a surface marker associated with poor outcome across genetic groups, which characterizes two leukemia stem cell (LSC)-enriched compartments with different self-renewal capacities. How these compartments self-renew remained unclear. Here, we show that GPR56+ LSC compartments are promoted in a complex network involving epithelial-to-mesenchymal transition (EMT) regulators besides Rho, Wnt, and Hedgehog (Hh) signaling. Unexpectedly, Wnt pathway inhibition increased the more immature, slowly cycling GPR56+ CD34+ fraction and Hh/EMT gene expression, while Wnt activation caused opposite effects. Our data suggest that the crucial role of GPR56 lies in its ability to co-activate these opposing signals, thus ensuring the constant supply of both LSC subsets. We show that CDK7 inhibitors suppress both LSC-enriched subsets in vivo and synergize with the Bcl-2 inhibitor venetoclax. Our data establish reciprocal transition between LSC compartments as a novel concept underlying the poor outcome in GPR56high AML and propose combined CDK7 and Bcl-2 inhibition as LSC-directed therapy in this disease.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Quinases Ciclina-Dependentes , Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Sulfonamidas , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Proteína Quinase CDC2/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Sinergismo Farmacológico , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , Sulfonamidas/farmacologia , Quinase Ativadora de Quinase Dependente de Ciclina
8.
Neural Regen Res ; 17(6): 1210-1227, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34782555

RESUMO

Age-related neurodegenerative disorders such as Alzheimer's disease (AD) have become a critical public health issue due to the significantly extended human lifespan, leading to considerable economic and social burdens. Traditional therapies for AD such as medicine and surgery remain ineffective, impractical, and expensive. Many studies have shown that a variety of bioactive substances released by physical exercise (called "exerkines") help to maintain and improve the normal functions of the brain in terms of cognition, emotion, and psychomotor coordination. Increasing evidence suggests that exerkines may exert beneficial effects in AD as well. This review summarizes the neuroprotective effects of exerkines in AD, focusing on the underlying molecular mechanism and the dynamic expression of exerkines after physical exercise. The findings described in this review will help direct research into novel targets for the treatment of AD and develop customized exercise therapy for individuals of different ages, genders, and health conditions.

9.
Fundam Res ; 2(6): 929-936, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38933379

RESUMO

X-ray free-electron lasers (FELs) provide cutting-edge tools for fundamental researches to study nature down to the atomic level at a time-scale that fits this resolution. A precise knowledge of temporal information of FEL pulses is the central issue for its applications. Here we proposed and demonstrated a novel method to determine the FEL temporal profiles online. This robust method, designed for ultrafast FELs, allows researchers to acquire real-time longitudinal profiles of FEL pulses as well as their arrive times with respect to the external optical laser with a resolution better than 6 fs. Based on this method, we can also directly measure various properties of FEL pulses and correlations between them online. This helps us to further understand the FEL lasing processes and realize the generation of stable, nearly fully coherent soft X-ray laser pulses at the Shanghai Soft X-ray FEL facility. This method will enhance the experimental opportunities for ultrafast science in various areas.

10.
Neuroimage ; 241: 118441, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34339832

RESUMO

In process of brain stimulation, the influence of any external stimulus depends on the features of the stimulus and the initial state of the brain. Understanding the state-dependence of brain stimulation is very important. However, it remains unclear whether neural activity induced by ultrasound stimulation is modulated by the behavioral state. We used low-intensity focused ultrasound to stimulate the hippocampal CA1 regions of mice with different behavioral states (anesthesia, awake, and running) and recorded the neural activity in the target area before and after stimulation. We found the following: (1) there were different spike firing rates and response delays computed as the time to reach peak for all behavioral states; (2) the behavioral state significantly modulates the spike firing rate linearly increased with an increase in ultrasound intensity under different behavioral states; (3) the mean power of local field potential induced by TUS significantly increased under anesthesia and awake states; (4) ultrasound stimulation enhanced phase-locking between spike and ripple oscillation under anesthesia state. These results suggest that ultrasound stimulation-induced neural activity is modulated by the behavioral state. Our study has great potential benefits for the application of ultrasound stimulation in neuroscience.


Assuntos
Potenciais de Ação/fisiologia , Região CA1 Hipocampal/fisiologia , Corrida/fisiologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Ondas Ultrassônicas , Vigília/fisiologia , Anestesia/métodos , Anestesia/tendências , Animais , Teste de Esforço/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
EMBO J ; 40(19): e108041, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34431536

RESUMO

The role of WNT/ß-catenin signalling in mouse neocortex development remains ambiguous. Most studies demonstrate that WNT/ß-catenin regulates progenitor self-renewal but others suggest it can also promote differentiation. Here we explore the role of WNT/STOP signalling, which stabilizes proteins during G2/M by inhibiting glycogen synthase kinase (GSK3)-mediated protein degradation. We show that mice mutant for cyclin Y and cyclin Y-like 1 (Ccny/l1), key regulators of WNT/STOP signalling, display reduced neurogenesis in the developing neocortex. Specifically, basal progenitors, which exhibit delayed cell cycle progression, were drastically decreased. Ccny/l1-deficient apical progenitors show reduced asymmetric division due to an increase in apical-basal astral microtubules. We identify the neurogenic transcription factors Sox4 and Sox11 as direct GSK3 targets that are stabilized by WNT/STOP signalling in basal progenitors during mitosis and that promote neuron generation. Our work reveals that WNT/STOP signalling drives cortical neurogenesis and identifies mitosis as a critical phase for neural progenitor fate.


Assuntos
Mitose , Neocórtex/embriologia , Neocórtex/metabolismo , Neurogênese , Via de Sinalização Wnt , Sequência de Aminoácidos , Animais , Biomarcadores , Ciclo Celular , Diferenciação Celular/genética , Ciclinas/genética , Ciclinas/metabolismo , Embrião de Mamíferos , Imunofluorescência , Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Mitose/genética , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Fosforilação , Fatores de Transcrição SOXC/genética , Fatores de Transcrição SOXC/metabolismo
12.
ACS Nano ; 15(6): 10488-10501, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34018736

RESUMO

Because of the deficiency of lymphatic reflux in the tumor, the retention of tumor interstitial fluid causes aggravation of the tumor interstitial pressure (TIP), which leads to unsatisfactory tumor penetration of nanomedicine. It is the main inducement of tumor recurrence and metastasis. Herein, we design a pyroelectric catalysis-based "Nano-lymphatic" to decrease the TIP for enhanced tumor penetration and treatments. It realizes photothermal therapy and decomposition of tumor interstitial fluid under NIR-II laser irradiation after reaching the tumor, which reduces the TIP for enhanced tumor penetration. Simultaneously, reactive oxygen species generated during the pyroelectric catalysis can further damage deep tumor stem cells. The results indicate that the "Nano-lymphatic" relieves 52% of TIP, leading to enhanced tumor penetration, which effectively inhibits the tumor proliferation (93.75%) and recurrence. Our finding presents a rational strategy to reduce TIP by pyroelectric catalysis for enhanced tumor penetration and improved treatments, which is of great significance for drug delivery.


Assuntos
Nanopartículas , Neoplasias , Catálise , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Hidrodinâmica , Neoplasias/tratamento farmacológico , Fototerapia
13.
Phys Rev Lett ; 126(8): 084801, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33709748

RESUMO

The spectroscopic techniques for time-resolved fine analysis of matter require coherent x-ray radiation with femtosecond duration and high average brightness. Seeded free-electron lasers (FELs), which use the frequency up-conversion of an external seed laser to improve temporal coherence, are ideal for providing fully coherent soft x-ray pulses. However, it is difficult to operate seeded FELs at a high repetition rate due to the limitations of present state-of-the-art laser systems. Here, we report a novel self-modulation method for enhancing laser-induced energy modulation, thereby significantly reducing the requirement of an external laser system. Driven by this scheme, we experimentally realize high harmonic generation in a seeded FEL using an unprecedentedly small external laser-induced energy modulation. An electron beam with a laser-induced energy modulation as small as 1.8 times the slice energy spread is used for lasing at the seventh harmonic of a 266-nm seed laser in a single-stage high-gain harmonic generation (HGHG) setup and the 30th harmonic of the seed laser in a two-stage HGHG setup. The results mark a major step toward a high-repetition-rate, fully coherent x-ray FEL.

14.
IEEE Trans Biomed Eng ; 68(5): 1619-1626, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33434119

RESUMO

OBJECTIVE: Low-intensity transcranial ultrasound stimulation (TUS) can induce motor responses, neural oscillation and hemodynamic responses. Early studies demonstrated that the motor responses evoked by TUS critically depend on anesthesia levels and ultrasound intensity. However, the neural mechanism of how anesthesia levels and ultrasound intensity influence on brain responses during TUS has never been explored yet. To investigate this question, we applied different anesthesia levels and ultrasound intensities on the visual cortex of mouse and observed neural oscillation change and hemodynamic responses during TUS. METHODS: low-intensity ultrasound was delivered to mouse visual cortex under different anesthesia levels, and simultaneous recordings for local field potentials (LFPs) and hemodynamic responses were carried out to measure and analyze the changes quantitatively. RESULTS: (i) The change of mean amplitude and mean relative power of sharp wave-ripple (SPW-R) in LFPs induced by TUS decreased as the anesthesia level increased (from awake to 1.5% isoflurane). (ii) The hemodynamic response level induced by TUS decreased as the anesthesia level increased (from awake to1.5% isoflurane). (iii) The coupling strength between neural activities and hemodynamic responses was dependent on anesthesia level. (iv) The neural activities and hemodynamic responses increase as a function of ultrasound intensity. CONCLUSION: These results support that the neural activities and hemodynamic response of the mouse visual cortex induced by TUS are related to the anesthesia level and ultrasound intensity. SIGNIFICANCE: This finding suggests that careful maintenance of anesthesia level and ultrasound intensity is required to acquire accurate LFP and hemodynamic data from samples with TUS.


Assuntos
Anestesia , Córtex Visual , Animais , Encéfalo , Hemodinâmica , Camundongos , Ultrassonografia
15.
Proc Natl Acad Sci U S A ; 112(43): 13342-7, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26460004

RESUMO

Previous data suggested a negative role of phosphatase and tensin homolog (Pten) and a positive function of SH2-containing tyrosine phosphatase (Shp2)/Ptpn11 in myelopoiesis and leukemogenesis. Herein we demonstrate that ablating Shp2 indeed suppressed the myeloproliferative effect of Pten loss, indicating directly opposing functions between pathways regulated by these two enzymes. Surprisingly, the Shp2 and Pten double-knockout mice suffered lethal anemia, a phenotype that reveals previously unappreciated cooperative roles of Pten and Shp2 in erythropoiesis. The lethal anemia was caused collectively by skewed progenitor differentiation and shortened erythrocyte lifespan. Consistently, treatment of Pten-deficient mice with a specific Shp2 inhibitor suppressed myeloproliferative neoplasm while causing anemia. These results identify concerted actions of Pten and Shp2 in promoting erythropoiesis, while acting antagonistically in myeloproliferative neoplasm development. This study illustrates cell type-specific signal cross-talk in blood cell lineages, and will guide better design of pharmaceuticals for leukemia and other types of cancer in the era of precision medicine.


Assuntos
Anemia/genética , Eritropoese/fisiologia , Mielopoese/fisiologia , PTEN Fosfo-Hidrolase/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Anemia/etiologia , Animais , Diferenciação Celular/genética , Primers do DNA/genética , Eritrócitos/fisiologia , Genótipo , Técnicas Histológicas , Camundongos , Camundongos Knockout , Mutagênese , PTEN Fosfo-Hidrolase/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Análise de Sobrevida
16.
Clin Cancer Res ; 21(20): 4676-85, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26071486

RESUMO

PURPOSE: Although a previous study reported nerve ending-derived acetylcholine promoted prostate cancer invasion and metastasis by regulating the microenvironment of cancer cells, the present study aims to determine whether there is autocrine cholinergic signaling in prostate epithelial cells that promotes prostate cancer growth and castration resistance. EXPERIMENTAL DESIGN: In this study, IHC was performed to detect protein expression in mouse prostate tissue sections and human prostate cancer tissue sections. Subcutaneously and orthotopically xenografted tumor models were established to evaluate the functions of autocrine cholinergic signaling in regulating prostate cancer growth and castration resistance. Western blotting analysis was performed to assess the autocrine cholinergic signaling-induced signaling pathway. RESULTS: We found the expression of choline acetyltransferase (ChAT), the secretion of acetylcholine and the expression of CHRM3 in prostate epithelial cells, supporting the presence of autocrine cholinergic signaling in the prostate epithelium. In addition, we found that CHRM3 was upregulated in clinical prostate cancer tissues compared with adjacent non-cancer tissues. Overexpression of CHRM3 or activation of CHRM3 by carbachol promoted cell proliferation, migration, and castration resistance. On the contrary, blockading CHRM3 by shRNA or treatment with darifenacin inhibited prostate cancer growth and castration resistance both in vitro and in vivo. Furthermore, we found that autocrine cholinergic signaling caused calmodulin/calmodulin-dependent protein kinase kinase (CaM/CaMKK)-mediated phosphorylation of Akt. CONCLUSIONS: These findings suggest that blockade of CHRM3 may represent a novel adjuvant therapy for castration-resistant prostate cancer.


Assuntos
Comunicação Autócrina/fisiologia , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Fosforilação/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Muscarínicos/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Próstata/metabolismo , Próstata/patologia , Receptor Muscarínico M3 , Transdução de Sinais/fisiologia , Regulação para Cima/genética
17.
Neuroreport ; 26(8): 473-7, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-25919994

RESUMO

Microenvironment and cell-cell interactions play an important role during embryogenesis and are required for the stemness and differentiation of stem cells. The inner-ear sensory epithelium, containing hair cells and supporting cells, is derived from the stem cells within the otic vesicle at early embryonic stages. However, whether or not such microenvironment or cell-cell interactions within the embryonic otic tissue have the capacity to regulate the proliferation and differentiation of stem cells and to autonomously reassemble the cells into epithelial structures is unknown. Here, we report that on enzymatic digestion and dissociation to harvest all the single cells from 13.5-day-old rat embryonic (E13.5) inner-ear tissue as well as on implantation of these cells under renal capsules; the dissociated cells are able to reassemble themselves to form epithelial structures as early as 7 days after implantation. By 25 days after implantation, more mature epithelial structures are formed. Immunostaining with cell-type-specific markers reveals that hair cells and supporting cells are not only formed, but are also well aligned with the hair cells located in the apical layer surrounded by the supporting cells. These findings suggest that microenvironment and cell-cell interactions within the embryonic inner-ear tissue have the autonomous signals to induce the formation of sensory epithelial structures. This method may also provide a useful system to study the potential of stem cells to differentiate into hair cells in vivo.


Assuntos
Orelha Interna/embriologia , Células Epiteliais/fisiologia , Epitélio/embriologia , Células Ciliadas Auditivas/fisiologia , Células-Tronco/fisiologia , Animais , Comunicação Celular , Diferenciação Celular , Microambiente Celular , Orelha Interna/citologia , Células Epiteliais/citologia , Células Ciliadas Auditivas/citologia , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia
18.
Cell Prolif ; 48(2): 209-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25677106

RESUMO

OBJECTIVES: Storkhead box 1 (STOX1) belongs to the forkhead family of transcription factors, and is reported to be involved in apoptosis of Caenorhabditis elegans. However, up to now the precise role of STOX1 in mammalian epithelial development has not been established. Here, we report that it plays an important role in regulation of proliferation of inner ear epithelial cells. MATERIALS AND METHODS: Immunohistochemistry and reverse transcription-PCR assays were used to determine expression pattern of STOX1 in the mouse inner ear. Furthermore, its overexpression and knockdown effects on mouse inner ear epithelial cells were studied using RT-PCR, immunofluorescence, MTT assay, BrdU labelling and western blotting. RESULTS: Storkhead box 1 was selectively expressed in epithelial cells, but not in stromal cells of the inner ear. Its over-expression enhanced cell proliferation and sphere formation, however, STOX1 knockdown inhibited cell proliferation and sphere formation in purified utricular epithelial cells in culture. Consistently, several cell cycle regulatory genes such as for PCNA, cyclin A and cyclin E, were up-regulated by STOX1 over-expression. Furthermore, biochemical analyses indicated that proliferation-promoting effects induced by STOX1 were mediated via phosphorylation of AKT in these cells. CONCLUSIONS: Taken together, we demonstrate that STOX1 is a novel stimulatory factor for inner ear epithelial cell proliferation and might be an important target to be considered in regeneration or repair of inner ear epithelium.


Assuntos
Proteínas de Transporte/genética , Células Epiteliais/metabolismo , Epitélio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sáculo e Utrículo/citologia , Animais , Proteínas de Transporte/biossíntese , Diferenciação Celular/genética , Proliferação de Células/genética , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Fosforilação/genética , Interferência de RNA , RNA Interferente Pequeno , Sáculo e Utrículo/metabolismo , Esferoides Celulares/metabolismo , Células Estromais/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
Exp Biol Med (Maywood) ; 239(7): 813-822, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24912507

RESUMO

Current androgen deprivation therapy often leads to androgen independence. However, mechanism of the therapeutic failure is still not well understood. Here, we demonstrate elevated expression of Zeb1 in androgen-independent prostate cancer cells and prostate tumors of castrated PTEN conditional knockout mice. While Zeb1 shRNA resulted in a sensitization of androgen-independent prostate cancer cells, forced Zeb1 expression caused androgen-dependent prostate cancer cells to be more resistant to androgen deprivation. Moreover, such effects appeared to be mediated by induction of pluripotent genes or stem cell-like properties. Collectively, these findings suggest that inhibition of Zeb1 might be a potential therapeutic strategy for treatment of androgen-independent prostate cancer.

20.
Oncol Rep ; 31(1): 34-40, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24173286

RESUMO

Androgen receptor (AR) plays a critical role during the development and progression of prostate cancer in which microRNA miR-375 is overexpressed and correlated with tumor progression. Although DNA methylation is a key mechanism for the repression of gene expression, the relationship between AR and the expression or the hypermethylation of miR-375 is unknown. In this study, we found that AR-positive prostate cancer (PCa) cells showed high expression levels and hypomethylation of the miR-375. In contrast, AR-negative PCa cells displayed low levels and hypermethylation of the miR-375. Addition of 5-Aza-2'-deoxycytidine, a specific inhibitor of DNA methylation, into the culture medium reversed the low expression levels of miR-375 in the AR negative PCa cells. In addition, the total activity levels of DNA methyltransferases (DNMTs) were high in AR-negative PCa cells, in which hypermethylation of miR-375 promoter and low expression levels of miR-375 were observed. Taken together, these findings indicate that the negative correlation between AR and total DNMT activity is one of mechanisms to influence the methylation status of miR-375 promoter, which in turn regulates the expression of miR-375.


Assuntos
Metilação de DNA/genética , MicroRNAs/genética , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/biossíntese , Decitabina , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , MicroRNAs/biossíntese , Regiões Promotoras Genéticas/genética , Interferência de RNA , RNA Interferente Pequeno , Ativação Transcricional/genética
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