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1.
BMC Plant Biol ; 24(1): 273, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605371

RESUMO

BACKGROUND: Environmental stresses negatively impact reproductive development and yield. Drought stress, in particular, has been examined during Arabidopsis reproductive development at morphological and transcriptomic levels. However, drought-responsive transcriptomic changes at different points in reproductive development remain unclear. Additionally, an investigation of the entire transcriptome at various stages during flower development is of great interest. RESULTS: Here, we treat Arabidopsis plants with well-watered and moderately and severely limiting water amounts when the first flowers reach maturity and generate RNA-seq datasets for early, middle, and late phases during flower development at 5, 6, and 7 days following treatment. Under different drought conditions, flowers in different developmental phases display differential sets of drought-responsive genes (DTGs), including those that are enriched in different GO functional categories, such as transcriptional regulation and response to stresses (early phase), lipid storage (middle phase), and pollen and seed development and metabolic processes (late phase). Some gene families have different members induced at different floral phases, suggesting that similar biochemical functions are carried out by distinct members. Developmentally-regulated genes (DVGs) with differential expression among the three floral phases belong to GO terms that are similar between water conditions, such as development and reproduction, metabolism and transport, and signaling and stress response. However, for different water conditions, such similar GO terms correspond to either distinct gene families or different members of a gene family, suggesting that drought affects the expression of distinct families or family members during reproductive development. A further comparison among transcriptomes of tissues collected on different days after treatment identifies differential gene expression, suggesting age-related genes (ARGs) might reflect the changes in the overall plant physiology in addition to drought response and development. CONCLUSION: Together, our study provides new insights into global transcriptome reprogramming and candidate genes for drought response, flower development, aging and coordination among these complex biological processes.


Assuntos
Arabidopsis , Transcriptoma , Arabidopsis/genética , Água , Reprodução/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Secas , Estresse Fisiológico/genética
2.
Annu Rev Genet ; 50: 235-266, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27648642

RESUMO

Single-stranded RNA molecules fold into extraordinarily complicated secondary and tertiary structures as a result of intramolecular base pairing. In vivo, these RNA structures are not static. Instead, they are remodeled in response to changes in the prevailing physicochemical environment of the cell and as a result of intermolecular base pairing and interactions with RNA-binding proteins. Remarkable technical advances now allow us to probe RNA secondary structure at single-nucleotide resolution and genome-wide, both in vitro and in vivo. These data sets provide new glimpses into the RNA universe. Analyses of RNA structuromes in HIV, yeast, Arabidopsis, and mammalian cells and tissues have revealed regulatory effects of RNA structure on messenger RNA (mRNA) polyadenylation, splicing, translation, and turnover. Application of new methods for genome-wide identification of mRNA modifications, particularly methylation and pseudouridylation, has shown that the RNA "epitranscriptome" both influences and is influenced by RNA structure. In this review, we describe newly developed genome-wide RNA structure-probing methods and synthesize the information emerging from their application.


Assuntos
Genômica/métodos , RNA/química , Bioquímica/métodos , Genoma , Conformação de Ácido Nucleico , Poliadenilação , Biossíntese de Proteínas , RNA/metabolismo , Processamento Pós-Transcricional do RNA , Splicing de RNA , Estabilidade de RNA , Spliceossomos/genética , Spliceossomos/metabolismo
3.
BMC Infect Dis ; 24(1): 743, 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39069620

RESUMO

BACKGROUND: Cysticercosis is a zoonotic parasitic disease that poses a serious threat to public health. It is widely distributed and has a high incidence rate in China. Reports of disseminated cysticercosis worldwide are rare. This article presents a case of disseminated cysticercosis in the Guangxi Zhuang Autonomous Region of southwestern China. CASE PRESENTATION: The patient, a 46-year-old male belonging to the Miao ethnic group, hailed from a region in Guangxi Zhuang Autonomous Region known for its high incidence of cysticercosis. He had a habit of consuming raw pork and beef. With a history of recurrent consciousness disturbances and limb convulsions for five years, he presented with headaches and dizziness nine days prior. Comprehensive examinations were conducted on the patient. Ultimately, based on epidemiological history, imaging findings, pathogen testing, and pathological results, he was diagnosed with disseminated cysticercosis. Following anthelmintic treatment, the patient was discharged with clear consciousness, free from headaches, dizziness, nausea, vomiting, and seizures. The patient is currently under follow-up care. CONCLUSION: It is crucial to enhance public awareness, promote health education, and cultivate good hygiene habits, as these are essential measures in reducing the incidence of cysticercosis.


Assuntos
Cisticercose , Humanos , Masculino , Pessoa de Meia-Idade , China/epidemiologia , Cisticercose/epidemiologia , Cisticercose/tratamento farmacológico , Cisticercose/diagnóstico , Animais , Anti-Helmínticos/uso terapêutico
4.
BMC Psychiatry ; 24(1): 187, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448895

RESUMO

BACKGROUND: Depression and anxiety are common and disabling mental health problems in children and young adults. Group cognitive behavioral therapy (GCBT) is considered that an efficient and effective treatment for these significant public health concerns, but not all participants respond equally well. The aim of this study was to examine the predictive ability of heart rate variability (HRV), based on sensor data from consumer-grade wearable devices to detect GCBT effectiveness in early intervention. METHODS: In a study of 33 college students with depression and anxiety, participants were randomly assigned to either GCBT group or a wait-list control (WLC) group. They wore smart wearable devices to measure their physiological activities and signals in daily life. The HRV parameters were calculated and compared between the groups. The study also assessed correlations between participants' symptoms, HRV, and GCBT outcomes. RESULTS: The study showed that participants in GCBT had significant improvement in depression and anxiety symptoms after four weeks. Higher HRV was associated with greater improvement in depressive and anxious symptoms following GCBT. Additionally, HRV played a noteworthy role in determining how effective GCBT was in improve anxiety(P = 0.002) and depression(P = 0.020), and its predictive power remained significant even when considering other factors. CONCLUSION: HRV may be a useful predictor of GCBT treatment efficacy. Identifying predictors of treatment response can help personalize treatment and improve outcomes for individuals with depression and anxiety. TRIAL REGISTRATION: The trial has been retrospectively registered on [22/06/2023] with the registration number [NCT05913349] in the ClinicalTrials.gov. Variations in heart rate variability (HRV) have been associated with depression and anxiety, but the relationship of baseline HRV to treatment outcome in depression and anxiety is unclear. This study predicted GCBT effectiveness using HRV measured by wearable devices. 33 students with depression and anxiety participated in a trial comparing GCBT and wait-list control. HRV parameters from wearables correlated with symptoms (PHQ, PSS) and GCBT effectiveness. Baseline HRV levels are strongly associated with GCBT treatment outcomes. HRV may serve as a useful predictor of efficacy of GCBT treatment,facilitating personalized treatment approaches for individuals with depression and anxiety.


Assuntos
Terapia Cognitivo-Comportamental , Dispositivos Eletrônicos Vestíveis , Criança , Adulto Jovem , Humanos , Frequência Cardíaca , Projetos de Pesquisa , Ansiedade/terapia
5.
RNA ; 26(4): 492-511, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31937672

RESUMO

Little is known concerning the effects of abiotic factors on in vivo RNA structures. We applied Structure-seq to assess the in vivo mRNA structuromes of Arabidopsis thaliana under salinity stress, which negatively impacts agriculture. Structure-seq utilizes dimethyl sulfate reactivity to identify As and Cs that lack base-pairing or protection. Salt stress refolded transcripts differentially in root versus shoot, evincing tissue specificity of the structurome. Both tissues exhibited an inverse correlation between salt stress-induced changes in transcript reactivity and changes in abundance, with stress-related mRNAs showing particular structural dynamism. This inverse correlation is more pronounced in mRNAs wherein the mean reactivity of the 5'UTR, CDS, and 3'UTR concertedly change under salinity stress, suggesting increased susceptibility to abundance control mechanisms in transcripts exhibiting this phenomenon, which we name "concordancy." Concordant salinity-induced increases in reactivity were notably observed in photosynthesis genes, thereby implicating mRNA structural loss in the well-known depression of photosynthesis by salt stress. Overall, changes in secondary structure appear to impact mRNA abundance, molding the functional specificity of the transcriptome under stress.


Assuntos
RNA Mensageiro/química , Tolerância ao Sal , Regiões 3' não Traduzidas , Regiões 5' não Traduzidas , Arabidopsis , Conformação de Ácido Nucleico , Especificidade de Órgãos , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma
6.
Acta Pharmacol Sin ; 43(11): 2873-2884, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35986214

RESUMO

Calpains have been implicated in heart diseases. While calpain-1 has been detrimental to the heart, the role of calpain-2 in cardiac pathology remains controversial. In this study we investigated whether sustained over-expression of calpain-2 had any adverse effects on the heart and the underlying mechanisms. Double transgenic mice (Tg-Capn2/tTA) were generated, which express human CAPN2 restricted to cardiomyocytes. The mice were subjected to echocardiography at age 3, 6, 8 and 12 months, and their heart tissues and sera were collected for analyses. We showed that transgenic mice over-expressing calpain-2 restricted to cardiomyocytes had normal heart function with no evidence of cardiac pathological remodeling at age 3 months. However, they exhibited features of dilated cardiomyopathy including increased heart size, enlarged heart chambers and heart dysfunction from age 8 months; histological analysis revealed loss of cardiomyocytes replaced by myocardial fibrosis and cardiomyocyte hypertrophy in transgenic mice from age 8 months. These cardiac alterations closely correlated with aberrant autophagy evidenced by significantly increased LC3BII and p62 protein levels and accumulation of autophagosomes in the hearts of transgenic mice. Notably, injection of 3-methyladenine, a well-established inhibitor of autophagy (30 mg/kg, i.p. once every 3 days starting from age 6 months for 2 months) prevented aberrant autophagy, attenuated myocardial injury and improved heart function in the transgenic mice. In cultured cardiomyocytes, over-expression of calpain-2 blocked autophagic flux by impairing lysosomal function. Furthermore, over-expression of calpain-2 resulted in lower levels of junctophilin-2 protein in the heart of transgenic mice and in cultured cardiomyocytes, which was attenuated by 3-methyladenine. In addition, blockade of autophagic flux by bafilomycin A (100 nM) induced a reduction of junctophilin-2 protein in cardiomyocytes. In summary, transgenic over-expression of calpain-2 induces age-dependent dilated cardiomyopathy in mice, which may be mediated through aberrant autophagy and a reduction of junctophilin-2. Thus, a sustained increase in calpain-2 may be detrimental to the heart.


Assuntos
Cardiomiopatia Dilatada , Camundongos , Animais , Humanos , Lactente , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Calpaína , Miócitos Cardíacos , Autofagia , Camundongos Transgênicos
7.
Hepatobiliary Pancreat Dis Int ; 21(2): 106-112, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34583911

RESUMO

Mammalian target of rapamycin (mTOR) inhibitor as an attractive drug target with promising antitumor effects has been widely investigated. High quality clinical trial has been conducted in liver transplant (LT) recipients in Western countries. However, the pertinent studies in Eastern world are paucity. Therefore, we designed a clinical trial to test whether sirolimus can improve recurrence-free survival (RFS) in hepatocellular carcinoma (HCC) patients beyond the Milan criteria after LT. This is an open-labeled, single-arm, prospective, multicenter, and real-world study aiming to evaluate the clinical outcomes of early switch to sirolimus-based regimens in HCC patients after LT. Patients with a histologically proven HCC and beyond the Milan criteria will be enrolled. The initial immunosuppressant regimens are center-specific for the first 4-6 weeks. The following regimens integrated sirolimus into the regimens as a combination therapy with reduced calcineurin inhibitors based on the condition of patients and centers. The study is planned for 4 years in total with a 2-year enrollment period and a 2-year follow-up. We predict that sirolimus conversion regimen will provide survival benefits for patients particular in the key indicator RFS as well as better quality of life. If the trial is conducted successfully, we will have a continued monitoring over a longer follow-up time to estimate indicator of overall survival. We hope that the outcome will provide better evidence for clinical decision-making and revising treatment guidelines based on Chinese population data. Trial register: Trial registered at http://www.chictr.org.cn: ChiCTR2100042869.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Humanos , Imunossupressores/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Prospectivos , Qualidade de Vida , Sirolimo/efeitos adversos , Resultado do Tratamento
8.
Proc Natl Acad Sci U S A ; 115(48): 12170-12175, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30413617

RESUMO

The heat shock response is crucial for organism survival in natural environments. RNA structure is known to influence numerous processes related to gene expression, but there have been few studies on the global RNA structurome as it prevails in vivo. Moreover, how heat shock rapidly affects RNA structure genome-wide in living systems remains unknown. We report here in vivo heat-regulated RNA structuromes. We applied Structure-seq chemical [dimethyl sulfate (DMS)] structure probing to rice (Oryza sativa L.) seedlings with and without 10 min of 42 °C heat shock and obtained structural data on >14,000 mRNAs. We show that RNA secondary structure broadly regulates gene expression in response to heat shock in this essential crop species. Our results indicate significant heat-induced elevation of DMS reactivity in the global transcriptome, revealing RNA unfolding over this biological temperature range. Our parallel Ribo-seq analysis provides no evidence for a correlation between RNA unfolding and heat-induced changes in translation, in contrast to the paradigm established in prokaryotes, wherein melting of RNA thermometers promotes translation. Instead, we find that heat-induced DMS reactivity increases correlate with significant decreases in transcript abundance, as quantified from an RNA-seq time course, indicating that mRNA unfolding promotes transcript degradation. The mechanistic basis for this outcome appears to be mRNA unfolding at both 5' and 3'-UTRs that facilitates access to the RNA degradation machinery. Our results thus reveal unexpected paradigms governing RNA structural changes and the eukaryotic RNA life cycle.


Assuntos
Genoma de Planta , Resposta ao Choque Térmico , Oryza/fisiologia , RNA Mensageiro/metabolismo , RNA de Plantas/genética , Temperatura Alta , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA de Plantas/metabolismo , Transcriptoma
9.
J Exp Bot ; 71(10): 2870-2885, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32072177

RESUMO

Plant responses to abiotic stresses during vegetative growth have been extensively studied for many years. Daily environmental fluctuations can have dramatic effects on plant vegetative growth at multiple levels, resulting in molecular, cellular, physiological, and morphological changes. Plants are even more sensitive to environmental changes during reproductive stages. However, much less is known about how plants respond to abiotic stresses during reproduction. Fortunately, recent advances in this field have begun to provide clues about these important processes, which promise further understanding and a potential contribution to maximize crop yield under adverse environments. Here we summarize information from several plants, focusing on the possible mechanisms that plants use to cope with different types of abiotic stresses during reproductive development, and present a tentative molecular portrait of plant acclimation during reproductive stages. Additionally, we discuss strategies that plants use to balance between survival and productivity, with some comparison among different plants that have adapted to distinct environments.


Assuntos
Desenvolvimento Vegetal , Estresse Fisiológico , Biologia Molecular , Desenvolvimento Vegetal/genética , Plantas/genética , Reprodução/genética
10.
Retina ; 40(9): 1783-1792, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31584558

RESUMO

PURPOSE: To determine the ability of nonperfusion, vessel density, and morphologic measurements using projection-resolved optical coherence tomography angiography to detect early retinal microvasculature impairments in diabetes mellitus. METHODS: A retrospective review was performed on Type 2 diabetes mellitus patients with no diabetic retinopathy (DR) or mild nonproliferative DR and age-matched controls imaged with optical coherence tomography angiography. Foveal avascular zone-related metrics and extrafoveal avascular area were measured in optical coherence tomography angiography images. Vessel density and fractal dimension were calculated with and without a skeletonization process. The vessel diameter index and vessel tortuosity were computed. The area under the receiver operating characteristic curve (AUC) estimated diagnostic performances. RESULTS: Dilated capillary diameter was observed in the deep capillary plexus in the diabetic groups. Vessel density and fractal dimension of skeletonized deep capillary plexus significantly and progressively decreased in the no DR and mild nonproliferative DR groups compared with controls. Superficial extrafoveal avascular area, vessel density, and fractal dimension of the skeletonized deep capillary plexus had the highest diagnostic performance to differentiate mild nonproliferative DR from control eyes, with AUCs of 0.885, 0.876, and 0.876, respectively. CONCLUSION: Vessel density and fractal dimension from the skeletonized deep capillary network may be the most sensitive for detecting early retinal capillary loss in diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Retinopatia Diabética/diagnóstico , Vasos Retinianos/patologia , Idoso , Área Sob a Curva , Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/fisiopatologia , Diagnóstico Precoce , Feminino , Angiofluoresceinografia , Fóvea Central/irrigação sanguínea , Humanos , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Curva ROC , Vasos Retinianos/diagnóstico por imagem , Estudos Retrospectivos , Tomografia de Coerência Óptica
11.
Plant Mol Biol ; 99(1-2): 161-174, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30604322

RESUMO

KEY MESSAGE: Morphological and transcriptomic evidences provide us strong support for the function of ANAC019 in reproductive development under drought stress. Plants are sensitive to drought conditions, particularly at the reproductive stage. Several studies have reported drought effects on crop reproductive development, but the molecular mechanism underlying drought response during reproduction is still unclear. A recent study showed that drought induces in Arabidopsis inflorescence increased expression of many genes, including ANAC019. However, the function of ANAC019 in drought response during reproductive development has not been characterized. Here, we report an investigation of the ANAC019 function in the response to drought during reproduction. ANAC019 is preferentially expressed in the inflorescence compared with the leaf, suggesting possible roles in regulating both stress response and flower development. The anac019 mutant was more sensitive to drought than WT plant, and exhibited a delay in recovery of floral organ development under prolonged drought stress. Moreover, many fewer genes were differentially expressed in the anac019 inflorescence under drought than that of WT, suggesting that the mutant was impaired in drought-induced gene expression. The genes affected by ANAC019 were associated with stress and hormone responses as well as floral development. In particular, the expression levels of several key drought-induced genes, DREB2A, DREB2B, ARF2, MYB21 and MYB24, were dramatically reduced in the absence of ANAC019, suggesting that ANAC019 is an upstream regulator these genes for drought response and flower development. These results provide strong support for the potential function of ANAC019 in reproductive development under drought stress.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Secas , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Inflorescência/fisiologia , Mutação , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Reprodução , Estresse Fisiológico , Fatores de Transcrição/genética
12.
Nucleic Acids Res ; 45(14): e135, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28637286

RESUMO

RNA serves many functions in biology such as splicing, temperature sensing, and innate immunity. These functions are often determined by the structure of RNA. There is thus a pressing need to understand RNA structure and how it changes during diverse biological processes both in vivo and genome-wide. Here, we present Structure-seq2, which provides nucleotide-resolution RNA structural information in vivo and genome-wide. This optimized version of our original Structure-seq method increases sensitivity by at least 4-fold and improves data quality by minimizing formation of a deleterious by-product, reducing ligation bias, and improving read coverage. We also present a variation of Structure-seq2 in which a biotinylated nucleotide is incorporated during reverse transcription, which greatly facilitates the protocol by eliminating two PAGE purification steps. We benchmark Structure-seq2 on both mRNA and rRNA structure in rice (Oryza sativa). We demonstrate that Structure-seq2 can lead to new biological insights. Our Structure-seq2 datasets uncover hidden breaks in chloroplast rRNA and identify a previously unreported N1-methyladenosine (m1A) in a nuclear-encoded Oryza sativa rRNA. Overall, Structure-seq2 is a rapid, sensitive, and unbiased method to probe RNA in vivo and genome-wide that facilitates new insights into RNA biology.


Assuntos
Perfilação da Expressão Gênica/métodos , Genoma de Planta/genética , Conformação de Ácido Nucleico , RNA de Plantas/química , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Modelos Genéticos , Oryza/genética , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Transcrição Reversa/genética , Análise de Sequência de DNA , Ésteres do Ácido Sulfúrico/química
13.
Plant Cell Environ ; 41(2): 451-468, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29216416

RESUMO

We studied physiological mechanisms of photoavoidance and photoprotection of a dwarf rice mutant with erect leaves, d1, in which the RGA1 gene, which encodes the Gα subunit of the heterotrimeric G protein, is non-functional. Leaves of d1 exhibit lower leaf temperature and higher photochemical reflectance index relative to wild type (WT), indicative of increased photoavoidance and more efficient light harvesting. RNA sequencing analysis of flag leaves revealed that messenger RNA levels of genes encoding heat shock proteins, enzymes associated with chlorophyll breakdown, and ROS scavengers were down-regulated in d1. By contrast, genes encoding proteins associated with light harvesting, Photosystem II, cyclic electron transport, Photosystem I, and chlorophyll biosynthesis were up-regulated in d1. Consistent with these observations, when WT and d1 plants were experimentally subjected to the same light intensity, d1 plants exhibited a greater capacity to dissipate excess irradiance (increased nonphotochemical quenching) relative to WT. The increased capacity in d1 for both photoavoidance and photoprotection reduced sustained photoinhibitory damage, as revealed by a higher Fv /Fm . We therefore propose RGA1 as a regulator of photoavoidance and photoprotection mechanisms in rice and highlight the prospect of exploiting modulation of heterotrimeric G protein signalling to increase these characteristics and improve the yield of cereals in the event of abiotic stress.


Assuntos
Oryza/metabolismo , Proteínas de Plantas/fisiologia , Clorofila/metabolismo , Perfilação da Expressão Gênica , Proteínas de Choque Térmico/metabolismo , Luz , Oryza/fisiologia , Oryza/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Complexo de Proteína do Fotossistema II/efeitos da radiação , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA
14.
Exp Cell Res ; 361(1): 19-29, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28964780

RESUMO

Gastric cancer tissue-derived mesenchymal stem cells (GC-MSCs) are important resident stromal cells in the tumor microenvironment (TME) and have been shown to play a key role in gastric cancer progression. Whether GC-MSCs exert a tumor-promoting function by affecting anti-tumor immunity is still unclear. In this study, we used GC-MSC conditioned medium (GC-MSC-CM) to pretreat peripheral blood mononuclear cells (PBMCs) from healthy donors. We found that GC-MSC-CM pretreatment markedly reversed the inhibitory effect of PBMCs on gastric cancer growth in vivo, but did not affect functions of PBMCs on gastric cancer cell proliferation, cell cycle and apoptosis in vitro. PBMCs pretreated with GC-MSC-CM significantly promoted gastric cancer migration and epithelial-mesenchymal transition in vitro and liver metastases in vivo. Flow cytometry analysis showed that GC-MSC-CM pretreatment increased the proportion of Treg cells and reduced that of Th17 cells in PBMCs. CFSE labeling and naïve CD4+ T cells differentiation analysis revealed that GC-MSC-CM disrupted the Treg/Th17 balance in PBMCs by suppressing Th17 cell proliferation and inducing differentiation of Treg cells. Overall, our collective results indicate that GC-MSCs impair the anti-tumor immune response of PBMCs through disruption of Treg/Th17 balance, thus providing new evidence that gastric cancer tissue-derived MSCs contribute to the immunosuppressive TME.


Assuntos
Leucócitos Mononucleares/imunologia , Células-Tronco Mesenquimais/imunologia , Neoplasias Peritoneais/secundário , Neoplasias Gástricas/patologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Apoptose , Ciclo Celular , Movimento Celular , Proliferação de Células , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Progressão da Doença , Transição Epitelial-Mesenquimal , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Peritoneais/imunologia , Neoplasias Peritoneais/patologia , Neoplasias Gástricas/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Plant Cell ; 25(10): 3785-807, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24179129

RESUMO

Drought dramatically affects plant growth and crop yield, but previous studies primarily examined responses to drought during vegetative development. Here, to study responses to drought during reproductive development, we grew Arabidopsis thaliana plants with limited water, under conditions that allowed the plants to initiate and complete reproduction. Drought treatment from just after the onset of flowering to seed maturation caused an early arrest of floral development and sterility. After acclimation, plants showed reduced fertility that persisted throughout reproductive development. Floral defects included abnormal anther development, lower pollen viability, reduced filament elongation, ovule abortion, and failure of flowers to open. Drought also caused differential expression of 4153 genes, including flowering time genes flowering locus t, suppressor of overexpression of CO1, and leafy, genes regulating anther and pistil development, and stress-related transcription factors. Mutant phenotypes of hypersensitivity to drought and fewer differentially expressed genes suggest that dehydration response element B1A may have an important function in drought response in flowers. A more severe filament elongation defect under drought in myb21 plants demonstrated that appropriate stamen development requires MYB domain protein 21 under drought conditions. Our study reveals a regulatory cascade in reproductive responses and acclimation under drought.


Assuntos
Aclimatação , Arabidopsis/crescimento & desenvolvimento , Secas , Flores/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reprodução , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
16.
BMC Plant Biol ; 14: 164, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24928551

RESUMO

BACKGROUND: Drought is a major constraint that leads to extensive losses to agricultural yield worldwide. The potential yield is largely determined during inflorescence development. However, to date, most investigations on plant response to drought have focused on vegetative development. This study describes the morphological changes of reproductive development and the comparison of transcriptomes under various drought conditions. RESULTS: The plants grown were studied under two drought conditions: minimum for successful reproduction (45-50% soil water content, moderate drought, MD) and for survival (30-35%, severe drought, SD). MD plants can produce similar number of siliques on the main stem and similar number of seeds per silique comparing with well-water plants. The situation of SD plants was much worse than MD plants. The transcriptomes of inflorescences were further investigated at molecular level using microarrays. Our results showed more than four thousands genes with differential expression under severe drought and less than two thousand changed under moderate drought condition (with 2-fold change and q-value < 0.01). We found a group of genes with increased expression as the drought became more severe, suggesting putative adaptation to the dehydration. Interestingly, we also identified genes with alteration only under the moderate but not the severe drought condition, indicating the existence of distinct sets of genes responsive to different levels of water availability. Further cis-element analyses of the putative regulatory sequences provided more information about the underlying mechanisms for reproductive responses to drought, suggesting possible novel candidate genes that protect those developing flowers under drought stress. CONCLUSIONS: Different pathways may be activated in response to moderate and severe drought in reproductive tissues, potentially helping plant to maximize its yield and balance the resource consumption between vegetative and reproductive development under dehydration stresses.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Secas , Flores/crescimento & desenvolvimento , Flores/genética , Transcriptoma/genética , Ácido Abscísico/metabolismo , Análise por Conglomerados , Regulação para Baixo/genética , Flores/anatomia & histologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Genes de Plantas , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Regiões Promotoras Genéticas/genética , Reprodução/genética , Transdução de Sinais/genética , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima
17.
Front Microbiol ; 15: 1359949, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500583

RESUMO

Diabetic retinopathy (DR) is a prevalent microvascular complication in diabetic patients that poses a serious risk as it can cause substantial visual impairment and even vision loss. Due to the prolonged onset of DR, lengthy treatment duration, and limited therapeutic effectiveness, it is extremely important to find a new strategy for the treatment of DR. Postbiotic is an emerging dietary supplement which consists of the inactivate microbiota and its metabolites. Numerous animal experiments have demonstrated that intervention with postbiotics reduces hyperglycemia, attenuates retinal peripapillary and endothelial cell damage, improves retinal microcirculatory dysfunction, and consequently delays the progression of DR. More strikingly, unlike conventional probiotics and prebiotics, postbiotics with small molecules can directly colonize the intestinal epithelial cells, and exert heat-resistant, acid-resistant, and durable for storage. Despite few clinical significance, oral administration with postbiotics might become the effective management for the prevention and treatment of DR. In this review, we summarized the basic conception, classification, molecular mechanisms, and the advances in the therapeutic implications of postbiotics in the pathogenesis of DR. Postbiotics present great potential as a viable adjunctive therapy for DR.

18.
Heliyon ; 10(13): e33485, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39040408

RESUMO

Utilizing computer-based scales for cognitive and psychological evaluations allows for the collection of objective data, such as response time. This cross-sectional study investigates the significance of response time data in cognitive and psychological measures, with a specific focus on its role in evaluating sleep quality through the Insomnia Severity Index (ISI) scale. A mobile application was designed to administer scale tests and collect response time data from 2729 participants. We explored the relationship between symptom severity and response time. A machine learning model was developed to predict the presence of insomnia symptoms in participants using response time data. The result revealed a statistically significant difference (p < 0.01) in the total response time between participants with or without insomnia symptom. Furthermore, a strong correlation was observed between the severity of specific insomnia aspects and the response times at the individual questions level. The machine learning model demonstrated a high predictive Area Under the ROC Curve (AUROC) of 0.824 in predicting insomnia symptoms based on response time data. These findings highlight the potential utility of response time data to evaluate cognitive and psychological measures.

19.
Proc Natl Acad Sci U S A ; 107(51): 22243-8, 2010 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-21127263

RESUMO

Astrocyte-elevated gene-1 (AEG-1) expression increases in multiple cancers and plays a crucial role in oncogenic transformation and angiogenesis, which are essential components in tumor cell development, growth, and progression to metastasis. Moreover, AEG-1 directly contributes to resistance to chemotherapeutic drugs, another important hallmark of aggressive cancers. In the present study, we document that AEG-1 mediates protective autophagy, an important regulator of cancer survival under metabolic stress and resistance to apoptosis, which may underlie its significant cancer-promoting properties. AEG-1 induces noncanonical autophagy involving an increase in expression of ATG5. AEG-1 decreases the ATP/AMP ratio, resulting in diminished cellular metabolism and activation of AMP kinase, which induces AMPK/mammalian target of rapamycin-dependent autophagy. Inhibition of AMPK by siAMPK or compound C decreases expression of ATG5, ultimately attenuating AEG-1-induced autophagy. AEG-1 protects normal cells from serum starvation-induced death through protective autophagy, and inhibition of AEG-1-induced autophagy results in serum starvation-induced cell death. We also show that AEG-1-mediated chemoresistance is because of protective autophagy and inhibition of AEG-1 results in a decrease in protective autophagy and chemosensitization of cancer cells. In summary, the present study reveals a previously unknown aspect of AEG-1 function by identifying it as a potential regulator of protective autophagy, an important feature of AEG-1 that may contribute to its tumor-promoting properties.


Assuntos
Autofagia , Moléculas de Adesão Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Monofosfato de Adenosina/genética , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/genética , Trifosfato de Adenosina/metabolismo , Adenilato Quinase , Proteína 5 Relacionada à Autofagia , Moléculas de Adesão Celular/genética , Linhagem Celular Transformada , Humanos , Masculino , Proteínas de Membrana , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/genética , Neoplasias/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Proteínas de Ligação a RNA , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
20.
Proc Natl Acad Sci U S A ; 107(26): 11948-53, 2010 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-20547861

RESUMO

MicroRNAs (miRNA), small noncoding RNAs, affect a broad range of biological processes, including tumorigenesis, by targeting gene products that directly regulate cell growth. Human polynucleotide phosphorylase (hPNPase(old-35)), a type I IFN-inducible 3'-5' exoribonuclease, degrades specific mRNAs and small noncoding RNAs. The present study examined the effect of this enzyme on miRNA expression in human melanoma cells. miRNA microarray analysis of human melanoma cells infected with empty adenovirus or with an adenovirus expressing hPNPase(old-35) identified miRNAs differentially and specifically regulated by hPNPase(old-35). One of these, miR-221, a regulator of the cyclin-dependent kinase inhibitor p27(kip1), displayed robust down-regulation with ensuing up-regulation of p27(kip1) by expression of hPNPase(old-35), which also occurred in multiple human melanoma cells upon IFN-beta treatment. Using both in vivo immunoprecipitation followed by Northern blotting and RNA degradation assays, we confirm that mature miR-221 is the target of hPNPase(old-35). Inhibition of hPNPase(old-35) by shRNA or stable overexpression of miR-221 protected melanoma cells from IFN-beta-mediated growth inhibition, accentuating the importance of hPNPase(old-35) induction and miR-221 down-regulation in mediating IFN-beta action. Moreover, we now uncover a mechanism of miRNA regulation involving selective enzymatic degradation. Targeted overexpression of hPNPase(old-35) might provide an effective therapeutic strategy for miR-221-overexpressing and IFN-resistant tumors, such as melanoma.


Assuntos
Melanoma/metabolismo , MicroRNAs/metabolismo , Polirribonucleotídeo Nucleotidiltransferase/metabolismo , RNA Neoplásico/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA/genética , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Técnicas In Vitro , Interferon Tipo I/farmacologia , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , MicroRNAs/genética , Modelos Biológicos , Polirribonucleotídeo Nucleotidiltransferase/antagonistas & inibidores , Polirribonucleotídeo Nucleotidiltransferase/genética , RNA Neoplásico/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
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