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1.
Sci Total Environ ; 928: 172449, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38615784

RESUMO

Nanoplastic represents an emerging abiotic stress facing modern agriculture, impacting global crop production. However, the molecular response of crop plants to this stress remains poorly understood at a spatiotemporal resolution. We therefore used RNA sequencing to profile the transcriptome expressed in rice (Oryza sativa) root and leaf organs at 1, 2, 4, and 8 d post exposure with nanoplastic. We revealed a striking similarity between the rice biomass dynamics in aboveground parts to that in belowground parts during nanoplastic stress, but transcriptome did not. At the global transcriptomic level, a total of 2332 differentially expressed genes were identified, with the majority being spatiotemporal specific, reflecting that nanoplastics predominantly regulate three processes in rice seedlings: (1) down-regulation of chlorophyll biosynthesis, photosynthesis, and starch, sucrose and nitrogen metabolism, (2) activation of defense responses such as brassinosteroid biosynthesis and phenylpropanoid biosynthesis, and (3) modulation of jasmonic acid and cytokinin signaling pathways by transcription factors. Notably, the genes involved in plant-pathogen interaction were shown to be successively modulated by both root and leaf organs, particularly plant disease defense genes (OsWRKY24, OsWRKY53, Os4CL3, OsPAL4, and MPK5), possibly indicating that nanoplastics affect rice growth indirectly through other biota. Finally, we associated biomass phenotypes with the temporal reprogramming of rice transcriptome by weighted gene co-expression network analysis, noting a significantly correlation with photosynthesis, carbon metabolism, and phenylpropanoid biosynthesis that may reflect the mechanisms of biomass reduction. Functional analysis further identified PsbY, MYB, cytochrome P450, and AP2/ERF as hub genes governing these pathways. Overall, our work provides the understanding of molecular mechanisms of rice in response to nanoplastics, which in turn suggests how rice might behave in a nanoplastic pollution scenario.


Assuntos
Oryza , Poliestirenos , Transcriptoma , Oryza/genética , Oryza/fisiologia , Estresse Fisiológico , Fotossíntese , Regulação da Expressão Gênica de Plantas , Folhas de Planta
2.
Biomimetics (Basel) ; 8(5)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37754176

RESUMO

Soft robotic gloves have attracted significant interest in hand rehabilitation in the past decade. However, current solutions are still heavy and lack finger-state monitoring and versatile treatment options. To address this, we present a lightweight soft robotic glove actuated by twisted string actuators (TSA) that provides whole-hand finger motion tracking. We have developed a virtual reality environment for hand rehabilitation training, allowing users to interact with various virtual objects. Fifteen small inertial measurement units are placed on the glove to predict finger joint angles and track whole-hand finger motion. We performed TSA experiments to identify design and control rules, by understanding how their response varies with input load and voltages. Grasping experiments were conducted to determine the grasping force and range of motion. Finally, we showcase an application of the rehabilitation glove in a Unity-based VR interface, which can actuate the operator's fingers to grasp different virtual objects.

3.
J Hazard Mater ; 447: 130770, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36640509

RESUMO

Co-contamination of soil from microplastics (MP) and arsenic (As) is becoming more prevalent, posing a severe threat to agricultural productivity. However, how this joint pollution affects crop growth needs to be better understood. To assess this, we investigated the transcriptomic and phenotypic patterns of rice (Oryza sativa) to MP, As, and their mixtures. The results revealed that, compared to As, MP had much less impact on rice growth, while the MP-As mixture decreased rice's aboveground biomass and altered As's biodistribution in rice tissues. Transcriptome further corroborated this pattern: 13 (294), 4195 (1842), and 3112 (2063) genes differentially regulated in response to MP, As, and their mixtures were observed in root (leaf) tissues, respectively. The joint application of MP and As produced a synergistic effect on crucial metabolic processes, such as carbohydrate, carboxylic acid, oxoacid, organic acid, amino acid, and tetrapyrrole metabolism. Moreover, we found that the joint stress reprogrammed the expression of hub genes encoding photosynthetic enzymes, protein kinases, and transcription factors, which likely reflect a transcript-driven tradeoff strategy between rice growth and defense. Together, these results strongly indicate that MP aggravated the As-induced toxicity in rice plants, which may impact the crop's acclimation to other abiotic field environments.


Assuntos
Arsênio , Oryza , Transcriptoma , Arsênio/metabolismo , Oryza/metabolismo , Plásticos/análise , Microplásticos/análise , Distribuição Tecidual , Folhas de Planta/metabolismo , Raízes de Plantas
4.
Immunopharmacol Immunotoxicol ; 45(2): 123-132, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36066109

RESUMO

OBJECTIVE: Alterations in intestinal function play a crucial role in the pathogenesis of sepsis, and the repair of the intestinal barrier is a potential strategy for the treatment of sepsis. Sestrin2 (SESN2), a highly conserved stress-responsive protein, can be induced in response to stress. AIM: This paper aimed to explore the role and mechanism of SESN2 in septic intestinal dysfunction. METHODS: Blood samples were collected from patients with septic intestinal dysfunction, and Caco-2 cells were subjected to lipopolysaccharide (LPS) to construct in vitro models. The expression level of SESN2 was determined in the blood samples and cells. The impacts of SESN2 overexpression on cell inflammation, oxidative stress, barrier integrity, and MAPK/Nrf2 signaling were evaluated. To determine the mediated role of MAPK signaling and ferroptosis, AMPK inhibitor (Compound C) and ferroptosis inducer (erastin) were separately used to treat cells, and the influences on the above aspects in cells were assessed. RESULTS: The expression level of SESN2 was down-regulated in patients with septic intestinal dysfunction and LPS-induced cells. SESN2 overexpression was found to suppress cell inflammation and oxidative stress, maintain barrier integrity, and activate AMPK/Nrf2 signaling. Following the AMPK signaling was inhibited or the ferroptosis was triggered, the effects of SESN2 overexpression on the cells were both reversed. CONCLUSION: Reduced SESN2 contributed to inflammatory response and barrier dysfunction in septic intestinal dysfunction by promoting ferroptosis via activating the AMPK/Nrf2 signaling pathway.


Assuntos
Ferroptose , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Células CACO-2 , Proteínas Quinases Ativadas por AMP/metabolismo , Lipopolissacarídeos/toxicidade , Inflamação , Sestrinas
5.
Chemosphere ; 292: 133501, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34995625

RESUMO

Understanding the cellular mechanisms mediating invasive plant adaptation to excessive cadmium (Cd) in environments is crucial for designing phytoremediation strategies for Cd-contaminated soils. Here we performed RNA sequencing on the root and leaf tissues of Solidago canadensis stressed by Cd for 0, 12, 24, and 48 h. Tissue-specific gene expression was notably significant, i.e., 76% (1667) of differentially expressed unigenes in the root and 78% (1856) in the leaf were exclusive to each tissue. Distinctive enrichment of gene functions was further observed in each tissue's response. In detail, adaptation of the root to Cd stress involved the up-regulation of genes encoding molecular chaperones (mainly heat shock proteins) and induction of some antioxidants, which may help cells scavenge reactive oxygen species (ROS). In comparison, leaf exposure to Cd ramped up the expression of genes associated with secondary metabolism, comprised mainly of cytochrome P450, but slowed down its photosynthetic functions, which seems to conserve energy for survival. Moreover, we highlighted candidate gene modules that are highly linked to physiological traits. Collectively, these observations suggest that S. canadensis may adopt a multipronged approach to actively cope with Cd stress, with both management of ROS accumulation and metabolic adjustment to optimize energy metabolism.


Assuntos
Cádmio , Solidago , Adaptação Fisiológica , Biodegradação Ambiental , Cádmio/metabolismo , Cádmio/toxicidade , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Solidago/metabolismo , Estresse Fisiológico/genética , Transcriptoma
6.
Int J Mol Sci ; 22(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34830223

RESUMO

This work investigates the mechanical properties, microstructures, and water-swelling behavior of a novel hydrogel filled with magnetic particles. The nanoparticles of magnetite (Fe3O4) and the micro-particles of carbonyl iron (CI) were selected and filled into a polyacrylamide (PAAM) hydrogel matrix to create two types of magnetic hydrogels. The isotropy and anisotropy of magnetic hydrogels are also presented in this study. The isotropic samples were cured without applying a magnetic field (MF), and the anisotropic samples were cured by applying an MF in the direction perpendicular to the thickness of the samples. The effects of the size, content, and inner structures of magnetic particles on the magneto-responsive and swelling properties of magnetic hydrogels were investigated. It was found that the magnetorheological (MR) effect of anisotropic samples was apparently higher than that of isotropic samples, and the hydrogels with CI exhibited a noticeable MR effect than those with Fe3O4. The storage modulus can be enhanced by increasing the filler content and size, forming an anisotropic structure, and applying an external MF. In addition, the magnetic hydrogels also have a swelling ability that can be tuned by varying the content and size of the particle fillers.


Assuntos
Resinas Acrílicas/química , Óxido Ferroso-Férrico/química , Hidrogéis/química , Compostos de Ferro/química , Nanopartículas de Magnetita/química , Solventes/química , Água/química , Anisotropia , Elasticidade , Campos Magnéticos , Tamanho da Partícula , Polimerização , Viscosidade
7.
Genes (Basel) ; 11(2)2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050732

RESUMO

Polyploid plants are more often invasive species than their diploid counterparts. As the invasiveness of a species is often linked to its production of allelopathic compounds, we hypothesize that differences in invasive ability between cytotypes may be due to their different ability to synthesize allelopathic metabolites. We test this using two cytotypes of Solidago canadensis as the model and use integrated metabolome and transcriptome data to resolve the question. Metabolome analysis identified 122 metabolites about flavonoids, phenylpropanoids and terpenoids, of which 57 were differentially accumulated between the two cytotypes. Transcriptome analysis showed that many differentially expressed genes (DEGs) were enriched in 'biosynthesis of secondary metabolites', 'plant hormone signal transduction', and 'MAPK signaling', covering most steps of plant allelopathic metabolite synthesis. Importantly, the differentially accumulated flavonoids, phenylpropanoids and terpenoids were closely correlated with related DEGs. Furthermore, 30 miRNAs were found to be negatively associated with putative targets, and they were thought to be involved in target gene expression regulation. These miRNAs probably play a vital role in the regulation of metabolite synthesis in hexaploid S. canadensis. The two cytotypes of S. canadensis differ in the allelopathic metabolite synthesis and this difference is associated with regulation of expression of a range of genes. These results suggest that changes in gene expression may underlying the increased invasive potential of the polyploidy.


Assuntos
Redes Reguladoras de Genes/genética , Metaboloma , Raízes de Plantas/metabolismo , Poliploidia , Solidago/metabolismo , Transcriptoma/genética , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/biossíntese , Flavonoides/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Ontologia Genética , Espécies Introduzidas , Sistema de Sinalização das MAP Quinases/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Raízes de Plantas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Solidago/química , Solidago/genética , Espectrometria de Massas em Tandem , Terpenos/análise
8.
RSC Adv ; 10(14): 8385-8395, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35497823

RESUMO

The semiconductor industry has witnessed a continuous decrease in the size of logic, memory and other computer chip components since its birth over half a century ago. The shrinking of features has to a large extent been enabled by the development of advanced photolithographic techniques. This review focuses on one important component of lithography, the resist, which is essentially a thin film that can generate a specific feature after an exposure and development process. Smaller features require an even more precisely focused photon, electron or ion beam with which to expose the resist. The promising light source for next generation lithography that will enable downscaling patterns to be written is extreme ultraviolet radiation (EUV), 92 eV (13.5 nm). The review mainly focuses on inorganic resists, as they have several advantages compared with traditional organic resists. In order to satisfy the throughput requirement in high volume semiconductor manufacturing, metal oxide resists with high resolution and sensitivity have been proposed and developed for EUV lithography. The progress of various inorganic resists is introduced and their properties have been summarized.

9.
Aging Clin Exp Res ; 32(11): 2217-2223, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31760610

RESUMO

AIMS: This study aimed at examining whether ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) were independently associated with carotid Intima-media thickness (CIMT) or carotid artery plaque (CAP) in elderly people. METHODS: A cross-sectional analysis was performed in 155 individuals aged over 75 years who underwent the measurements of ABI and baPWV. Low ABI was defined as ABI ≤ 1.0. High baPWV was defined as baPWV > 2000 cm/s. The CIMT and CAP were measured with a B-mode tomographic ultrasound system. RESULTS: Neither ABI nor baPWV was associated with CIMT in this elderly population. The group with low ABI (≤ 1.0) was significantly associated with a higher prevalence of carotid plaque (P = 0.001), while the relationship between baPWV and prevalence of carotid plaque was not found. Linear regression analysis showed that the value of ABI was significantly associated with the thickness of carotid plaque. Even in the full adjusted model, each 0.01unit ABI decreasing still increased 0.1663 mm of carotid plaque thickness (P = 0.004). Logistic Regression Analysis demonstrated that ABI lower than 1.0 had predictive value in the formation of carotid plaque with top quartile thickness (OR 2.834, 95% CI 1.131-7.099, P = 0.026). Furthermore, individuals with low ABI (≤ 1.0) were more likely to form hypoechoic carotid plaques according to ultrasonography. CONCLUSION: Low ABI but not high baPWV was associated with the formation of carotid plaque. Furthermore, ABI was significantly associated with the thickness and morphology of carotid plaque in elderly people.


Assuntos
Índice Tornozelo-Braço , Peste , Idoso , Espessura Intima-Media Carotídea , Estudos Transversais , Humanos , Análise de Onda de Pulso
10.
IEEE Trans Neural Syst Rehabil Eng ; 27(10): 2216-2228, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31443038

RESUMO

Lower extremity paralysis has become common in recent years, and robots have been developed to help patients recover from it. This paper presents such a robotic system that allows for two working modes, the robot-active mode and human-active mode. The robot is designed to be equipped with magnetorheological (MR) actuators that have the advantages of high torque, fast response, flexible controllability, low power consumption and safety guarantee. The design and characteristics of the MR actuator are introduced. In the robot-active mode, the MR actuator works as a clutch to transfer the torque to the robotic joint safely. In the human-active mode, the MR actuator functions as a brake to provide resistance to help strengthen muscles. The working mode is determined by the human motion intention, which is detected via the skin surface electromyography (EMG) signals. The human-robot interaction torques are estimated using the EMG-driven impedance model. The biomechanical analysis based on AnyBody Modeling System (AMS) is used to help optimization. Then, an adaptive control method is proposed to realize the assist-as-needed (AAN) training strategy, where the robot can switch between these two modes. Experiments are conducted to validate the proposed design.


Assuntos
Intenção , Movimento/fisiologia , Reabilitação/instrumentação , Robótica , Fenômenos Biomecânicos , Eletromiografia , Exercício Físico , Exoesqueleto Energizado , Voluntários Saudáveis , Humanos , Prótese Articular , Extremidade Inferior , Campos Magnéticos , Masculino , Reologia , Tecnologia Assistiva , Torque , Adulto Jovem
11.
Ecol Evol ; 9(8): 4820-4852, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31031947

RESUMO

Dissecting complex connections between cytogenetic traits (ploidy levels) and plant invasiveness has emerged as a popular research subject in the field of invasion biology. Although recent work suggests that polyploids are more likely to be invasive than their corresponding diploids, the molecular basis underlying the successful invasion of polyploids remains largely unexplored. To this end, we adopted an RNA-seq and sRNA-seq approach to describe how polyploids mediate invasiveness differences in two contrasting cytotypes of Solidago canadensis L., a widespread wild hexaploid invader with localized cultivated diploid populations. Our analysis of the leaf transcriptome revealed 116,801 unigenes, of which 12,897 unigenes displayed significant differences in expression levels. A substantial number of these differentially expressed unigenes (DEUs) were significantly associated with the biosynthesis of secondary metabolites, carbohydrate metabolism, lipid metabolism, and environmental adaptation pathways. Gene Ontology term enrichment-based categorization of DEU-functions was consistent with this observation, as terms related to single-organism, cellular, and metabolic processes including catalytic, binding, transporter, and enzyme regulator activity were over-represented. Concomitantly, 186 miRNAs belonging to 44 miRNA families were identified in the same leaf tissues, with 59 miRNAs being differentially expressed. Furthermore, we discovered 83 miRNA-target interacting pairs that were oppositely regulated, and a meticulous study of these targets depicted that several unigenes encoding transcription factors, DNA methyltransferase, and leucine-rich repeat receptor-like kinases involved in the stress response were greatly influenced. Collectively, these transcriptional and epigenetic data provide new insights into miRNA-mediated gene expression regulatory mechanisms that may operate in hexaploid cytotypes to favor successful invasion.

12.
Z Gerontol Geriatr ; 50(3): 233-238, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27115524

RESUMO

OBJECTIVE: This study was carried out to determine whether changes in hemorheological parameters parallel the severity of essential hypertension. METHODS: A total of 198 older hypertensive patients were recruited and classified into 3 stages of hypertension according to the grading standard of hypertension. The whole blood viscosity (WBV) at various shear rates, plasma viscosity and erythrocyte rheology (including erythrocyte rigidity index, erythrocyte aggregation index and erythrocyte deformation index) were examined. RESULTS: Erythrocyte rheology paralleled the severity of essential hypertension and was significantly correlated to the average 24 h systolic blood pressure and diastolic blood pressure. Logistic analysis revealed that erythrocyte rigidity and the erythrocyte aggregation index were positively correlated with the severity of hypertension, while the erythrocyte deformation index was negatively correlated. No association was found between WBV, plasma viscosity and the severity of hypertension. CONCLUSION: The rheological properties of erythrocyte viscosity were correlated with the severity of hypertension in older people but the WBV and plasma viscosity were not.


Assuntos
Viscosidade Sanguínea , Eritrócitos , Hipertensão Essencial/sangue , Hipertensão Essencial/diagnóstico , Avaliação Geriátrica/métodos , Índice de Gravidade de Doença , Idoso de 80 Anos ou mais , Deformação Eritrocítica , Hipertensão Essencial/classificação , Feminino , Testes Hematológicos/métodos , Humanos , Masculino , Plasma , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
PLoS One ; 10(8): e0134009, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26252952

RESUMO

In constructing and visualizing a virtual three-dimensional forest scene, we must first obtain the vegetation distribution, namely, the location of each plant in the forest. Because the forest contains a large number of plants, the distribution of each plant is difficult to obtain from actual measurement methods. Random approaches are used as common solutions to simulate a forest distribution but fail to reflect the specific biological arrangements among types of plants. Observations show that plants in the forest tend to generate particular distribution patterns due to growth competition and specific habitats. This pattern, which represents a local feature in the distribution and occurs repeatedly in the forest, is in line with the "locality" and "static" characteristics in the "texture data", making it possible to use a sample-based texture synthesis strategy to build the distribution. We propose a vegetation distribution data generation method that uses sample-based vector pattern synthesis. A sample forest stand is obtained first and recorded as a two-dimensional vector-element distribution pattern. Next, the large-scale vegetation distribution pattern is synthesized automatically using the proposed vector pattern synthesis algorithm. The synthesized distribution pattern resembles the sample pattern in the distribution features. The vector pattern synthesis algorithm proposed in this paper adopts a neighborhood comparison technique based on histogram matching, which makes it efficient and easy to implement. Experiments show that the distribution pattern synthesized with this method can sufficiently preserve the features of the sample distribution pattern, making our method meaningful for constructing realistic forest scenes.


Assuntos
Plantas , Análise por Conglomerados , Florestas , Reconhecimento Automatizado de Padrão
14.
Endocrine ; 42(3): 676-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22588951

RESUMO

Osteopontin (OPN) is known to be one of the cytokines that is involved in the vascular inflammation caused by aldosterone (Ald). Previous reports have shown that Ald increases OPN expression, and the mechanisms for this remain to be clarified. In this study, we investigated how Ald increases OPN expression in the vascular smooth muscle cells (VSMCs) of rats. Ald increased OPN expression time dependently as well as dose dependently. This increase was diminished by spironolactone, a mineralocorticoid receptor (MR) antagonist. PD98059, an inhibitor of p42/44 MAPK pathway, and SB203580, an inhibitor of p38 MAPK pathway, suppressed Ald-induced OPN expression and secretion in VSMCs. VSMCs migration stimulated by aldosterone required OPN expression. In conclusion, these data suggest that Ald-induced OPN expression in VSMC is mediated by MR and signaling cascades involving ERK and p38 MAPK. These molecules may represent therapeutic targets for the prevention of pathological vascular remodeling.


Assuntos
Aldosterona/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Osteopontina/biossíntese , Receptores de Mineralocorticoides/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Aorta Torácica/citologia , Aorta Torácica/efeitos dos fármacos , Western Blotting , Lesões das Artérias Carótidas/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Luciferases/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Neointima/patologia , Oligonucleotídeos Antissenso/farmacologia , Ratos , Ratos Sprague-Dawley , Transfecção , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
15.
Biochem Biophys Res Commun ; 400(4): 483-8, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20735984

RESUMO

MicroRNAs (miRNAs), which are genomically encoded small RNAs, negatively regulate target gene expression at the post-transcriptional level. Our recent study indicated that microRNA-155 (miR-155) might be negatively correlated with blood pressure, and it has been suggested that miR-155-mediated target genes could be involved in the cardiovascular diseases. Bioinformatic analyses predict that angiotensin II type 1 receptor (AT(1)R) is a miR-155 target gene. The present study investigated the potential role of miR-155 in regulating AT(1)R expression and phenotypic differentiation in rat aortic adventitial fibroblasts (AFs). Luciferase assay demonstrated that miR-155 suppressed AT(1)R 3'-UTR reporter construct activity. miR-155 overexpression in AFs did not reduce target mRNA levels, but significantly reduced target protein expression. In addition, AFs transfected with pSUPER/miR-155 exhibited reduced Ang II-induced ERK1/2 activation. miR-155 overexpression in cells attenuated Ang II-induced α-smooth muscle actin (α-SMA, produces myofibroblast) expression, but did not transform growth factor beta-1 (TGF-ß1). This study demonstrated that miR-155 could have an important role in regulating adventitial fibroblast differentiation and contribute to suppression of AT(1)R expression.


Assuntos
Aorta Torácica/citologia , Diferenciação Celular/genética , Fibroblastos/citologia , Regulação da Expressão Gênica , Hipertensão/genética , MicroRNAs/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Aorta Torácica/metabolismo , Células Cultivadas , Regulação para Baixo , Fibroblastos/metabolismo , Luciferases/genética , MicroRNAs/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley
16.
Sheng Li Xue Bao ; 60(4): 553-60, 2008 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-18690400

RESUMO

MicroRNAs (miRNAs) are genomically encoded non-protein-encoding small RNAs, which negatively regulate target gene expression at post-transcriptional level. The present study aimed to investigate whether disorders of miRNAs system were involved in the pathogenesis of hypertension in spontaneously hypertensive rats (SHR). MiRanda, Target Scan and PicTar were utilized for predictive analysis of miRNAs and target genes. MiR-1, miR-133a, miR-155 and miR-208 were selected as the candidate miRNAs potentially related to blood pressure. The expression levels of miR-1, miR-133a, miR-155 and miR-208 in the aorta of 4-, 8-, 16- and 24-week-old SHR and age-matched Wistar-Kyoto (WKY) rats were detected by real-time RT-PCR. The mRNA levels of angiotensin II receptor type 1 (AGTR1a), angiotensin II receptor associated protein (AGTRAP), divalent metal transporter 1 (DMT1), low-density lipoprotein-related protein 1B (LRP1B), fibroblast growth factor-7 (FGF-7), protocadherin 9 precursor (PCDH9), chloride channel protein 5 (CLCN-5), small conductance calcium activated potassium channel protein 3 (KCNN3) and thyroid hormone receptor associated protein 1 (THRAP1), which were predicted to be target genes of differentially expressed miRNAs, were further detected by real-time RT-PCR. The results obtained showed that the expression levels of miR-1, miR-155 and miR-208 in the aorta were significantly different from those in the heart of WKY rats. The miR-155 level was significantly lower in aorta of 16-week-old SHR than that of age-matched WKY rats (P<0.05), but there was no difference between SHR and WKY rats in other age groups. In addition, miR-155 level was negatively correlated to blood pressure (r=-0.525, P<0.05). Both in WKY rats and SHR, miR-208 was most abundantly expressed in 4-week-old rats, but declined significantly in 8-, 16- and 24-week-old rats (P<0.05). No difference in miR-208 levels was observed between age-matched SHR and WKY rats. Moreover, miR-208 expression in aorta was negatively correlated with blood pressure (r=-0.400, P<0.05) and age (r=-0.684, P<0.0001). Neither miR-1 nor miR-133a was differentially expressed in SHR and WKY rats in different age groups. The mRNA levels of predicted target genes were not correlated to miR-155 or miR-208 levels. These results indicate that miR-155 is less expressed in the aorta of adult SHR compared with that of WKY rats and is negatively correlated with blood pressure, suggesting it is possibly involved in the development and pathologic progress of hypertension. The miR-208 expression in rat aorta declines with aging and it may play a role in the blood vessel development.


Assuntos
Aorta/metabolismo , Pressão Sanguínea , Hipertensão/metabolismo , MicroRNAs/metabolismo , Animais , RNA Mensageiro , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
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