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1.
Plant Cell Environ ; 47(6): 2258-2273, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38482979

RESUMO

Sirtuins (SRTs) are a group of nicotinamide adenine dinucleotide (NAD+)-dependent deacetylase that target both histone and nonhistone proteins. The biological function of SRT in horticultural plants has been rarely studied. In this study, FaSRT1-2 was identified as a key member of the 8 FaSRTs encoded in cultivated strawberry genome. Transient overexpression of FaSRT1-2 in strawberry fruit accelerated ripening, increased the content of anthocyanins and sugars, enhanced ripening-related gene expression. Moreover, stable transformation of FaSRT1-2 in strawberry plants resulted in enhanced vegetative growth, increased sensitivity to heat stress and increased susceptibility to Botrytis cinerea infection. Interestingly, knocking out the homologous gene in woodland strawberry had the opposite effects. Additionally, we found the content of stress-related hormone abscisic acid (ABA) was decreased, while the growth-related gibberellin (GA) concentration was increased in FaSRT1-2 overexpression lines. Gene expression analysis revealed induction of heat shock proteins, transcription factors, stress-related and antioxidant genes in the FaSRT1-2-overexpressed plants while knocked-out of the gene had the opposite impact. In conclusion, our findings demonstrated that FaSRT1-2 could positively promote strawberry plant vegetative growth and fruit ripening by affecting ABA and GA pathways. However, it negatively regulates the resistance to heat stress and B. cinerea infection by influencing the related gene expression.


Assuntos
Botrytis , Fragaria , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fragaria/genética , Fragaria/crescimento & desenvolvimento , Fragaria/fisiologia , Fragaria/metabolismo , Frutas/genética , Frutas/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Botrytis/fisiologia , Histona Desacetilases/metabolismo , Histona Desacetilases/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Ácido Abscísico/metabolismo , Estresse Fisiológico/genética , Reguladores de Crescimento de Plantas/metabolismo , Giberelinas/metabolismo , Plantas Geneticamente Modificadas , Resistência à Doença/genética
2.
Appl Microbiol Biotechnol ; 108(1): 125, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38229330

RESUMO

The gut microbiota is the largest and most complex microecosystem in animals. It is influenced by the host's dietary habits and living environment, and its composition and diversity play irreplaceable roles in animal nutrient metabolism, immunity, and adaptation to the environment. Although the gut microbiota of red deer has been studied, the composition and function of the gut microbiota in Gansu red deer (Cervus elaphus kansuensis), an endemic subspecies of red deer in China, has not been reported. In this study, the composition and diversity of the gut microbiome and fecal metabolomics of C. elaphus kansuensis were identified and compared for the first time by using 16S rDNA sequencing, metagenomic sequencing, and LC-MS/MS. There were significant differences in gut microbiota structure and diversity between wild and farmed C. elaphus kansuensis. The 16S rDNA sequencing results showed that the genus UCRD-005 was dominant in both captive red deer (CRD) and wild red deer (WRD). Metagenomic sequencing showed similar results to those of 16S rDNA sequencing for gut microbiota in CRD and WRD at the phylum and genus levels. 16S rDNA and metagenomics sequencing data suggested that Bacteroides and Bacillus might serve as marker genera for CRD and WRD, respectively. Fecal metabolomics results showed that 520 metabolites with significant differences were detected between CRD and WRD and most differential metabolites were involved in lipid metabolism. The results suggested that large differences in gut microbiota composition and fecal metabolites between CRD and WRD, indicating that different dietary habits and living environments over time have led to the development of stable gut microbiome characteristics for CRD and WRD to meet their respective survival and reproduction needs. KEY POINTS: • Environment and food affected the gut microbiota and fecal metabolites in red deer • Genera Bacteroides and Bacillus may play important roles in CRD and WRD, respectively • Flavonoids and ascorbic acid in fecal metabolites may influence health of red deer.


Assuntos
Bacillus , Cervos , Microbioma Gastrointestinal , Animais , Microbioma Gastrointestinal/genética , Cromatografia Líquida , Espectrometria de Massas em Tandem , Bacillus/genética , DNA Ribossômico/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
3.
Front Endocrinol (Lausanne) ; 14: 1138513, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37564990

RESUMO

Background: Globally, chronic kidney disease (CKD) is a growing public health concern. Serum uric acid (SUA) is an easily detectable and readily available biochemical indicator that has long been recognized as an independent risk factor for CKD. In addition, studies have indicated a potential relationship between SUA and body mass index (BMI). However, studies on the effect of SUA levels on the estimated glomerular filtration rate (eGFR) in adolescents with different BMIs are very rare. Methods: Weighted multiple regression analysis was used to estimate the independent relationship between SUA and log-transformed eGFR. Additionally, we used a weighted generalized additive model and smooth curve fitting to describe the nonlinear relationships in the subgroup analysis. Results: First, SUA was negatively associated with log-transformed eGFR even after adjusting for all covariates (ß=-0.0177, 95% CI: -0.0203-0.0151, P<0.0001). Second, the results of the stratified analysis found that after adjusting for all covariates, the decrease in log-transformed eGFR due to changes in per SUA levels (Per 1, mg/dL increase) was elevated in female adolescents (ß=-0.0177, 95% CI: -0.0216, -0.0138, P<0.0001), adolescents aged 12-15 years (ß=-0.0163, 95% CI: -0.0200, -0.0125, P<0.0001) and black (ß=-0.0199, 95% CI: -0.0251, -0.0148, P<0.0001) adolescents. Furthermore, we found that adolescents with a higher BMI had higher SUA levels, and the effect of SUA on eGFR was significantly higher in underweight adolescents (ß=-0.0386, 95% CI: (-0.0550, -0.0223), P<0.0001). Conclusion: SUA was negatively associated with the eGFR in adolescents aged 12-19 years. Furthermore, we found for the first time that SUA affects the eGFR differently in adolescents with different BMIs. This effect was particularly significant in underweight adolescents.

4.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298465

RESUMO

Ascorbic acid (AsA) is a crucial water-soluble antioxidant in strawberry fruit, but limited research is currently available on the identification and functional validation of key genes involved in AsA metabolism in strawberries. This study analyzed the FaMDHAR gene family identification, which includes 168 genes. Most of the products of these genes are predicted to exist in the chloroplast and cytoplasm. The promoter region is rich in cis-acting elements related to plant growth and development, stress and light response. Meanwhile, the key gene FaMDHAR50 that positively regulates AsA regeneration was identified through comparative transcriptome analysis of 'Benihoppe' strawberry (WT) and its natural mutant (MT) with high AsA content (83 mg/100 g FW). The transient overexpression experiment further showed that overexpression of FaMDHAR50 significantly enhanced the AsA content by 38% in strawberry fruit, with the upregulated expression of structural genes involved in AsA biosynthesis (FaGalUR and FaGalLDH) and recycling and degradation (FaAPX, FaAO and FaDHAR) compared with that of the control. Moreover, increased sugar (sucrose, glucose and fructose) contents and decreased firmness and citric acid contents were observed in the overexpressed fruit, which were accompanied by the upregulation of FaSNS, FaSPS, FaCEL1 and FaACL, as well as the downregulation of FaCS. Additionally, the content of pelargonidin 3-glucoside markedly decreased, while cyanidin chloride increased significantly. In summary, FaMDHAR50 is a key positive regulatory gene involved in AsA regeneration in strawberry fruit, which also plays an important role in the formation of fruit flavor, apperance and texture during strawberry fruit ripening.


Assuntos
Ácido Ascórbico , Fragaria , Ácido Ascórbico/metabolismo , Fragaria/metabolismo , Transcriptoma , Frutas/metabolismo , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo
5.
Front Plant Sci ; 14: 1138865, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082348

RESUMO

Citric acid is the primary organic acid that affects the taste of strawberry fruit. Glycolysis supplies key substrates for the tricarboxylic acid cycle (TCA cycle). However, little is known about the regulatory mechanisms of glycolytic genes on citric acid metabolism in strawberry fruits. In this study, the citric acid content of strawberry fruit displayed a trend of rising and decreasing from the initial red stage to the full red stage and then dark red stage. Thus, a difference in citric acid metabolic regulation was suspected during strawberry fruit development. In addition, overexpression of either cytoplasm glyceraldehyde-3-phosphate dehydrogenase (FxaC_14g13400, namely FaGAPC2) or pyruvate kinase (FxaC_15g00080, namely FaPKc2.2) inhibited strawberry fruit ripening and the accumulation of citric acid, leading to a range of maturity stages from partial red to full red stage. The combined transcriptome and metabolome analysis revealed that overexpression of FaGAPC2 and FaPKc2.2 significantly suppressed the expression of phosphoenolpyruvate carboxykinase (FxaC_1g21491, namely FaPEPCK) but enhanced the content of glutamine and aspartic acid. Meanwhile, the activities of PEPCK and glutamate decarboxylase (GAD) were inhibited, but the activities of glutamine synthase (GS) were increased in FaGAPC2/FaPKc2.2-overexpressed fruit. Further, functional verification demonstrated that overexpression of FaPEPCK can promote strawberry fruit ripening, resulting in a range of maturity stage from full red to dark red stage, while the citric acid synthase (CS) activities and citric acid content were significantly decreased. Overall, this study revealed that FaGAPC2/FaPKc2.2 and FaPEPCK perform an important role in reducing citric acid content in strawberry fruit, and FaGAPC2/FaPKc2.2 mainly by promoting the GS degradation pathway and FaPEPCK mainly by inhibiting the CS synthesis pathway.

6.
Biochem Biophys Res Commun ; 655: 50-58, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-36933307

RESUMO

Serious intestinal side-effects that target the NOTCH-HES1 pathway in human cancer differentiation therapy make it necessary to understand the pathway at the human organ level. Herein, we endogenously introduced HES1-/- mutations into human embryonic stem cells (hESCs) and differentiated them into human intestinal organoids (HIO). The HES1-/- hESCs retained ES cell properties and showed gene expression patterns similar to those of wild-type hESCs when they differentiated into definitive endoderm and hindgut. During the formation of the HES1-/- lumen we noted an impaired development of mesenchymal cells in addition to the increased differentiation of secretory epithelium. RNA-Seq revealed that inhibited development of the mesenchymal cells may have been due to a downregulation of WNT5A signaling. Overexpression of HES1 and silencing of WNT5A in the intestinal fibroblast cell line CCD-18Co indicated that HES1 was involved in the activation of WNT5A-induced fibroblast growth and migration, suggesting the likelihood of the Notch pathway in epithelial-mesenchymal crosstalk. Our results facilitated the identification of more precise underlying molecular mechanisms displaying distinct roles in HES1 signaling in stromal and epithelial development in human intestinal mucosa.


Assuntos
Mucosa Intestinal , Intestinos , Humanos , Diferenciação Celular/genética , Mucosa Intestinal/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco Embrionárias , Fatores de Transcrição HES-1/genética , Fatores de Transcrição HES-1/metabolismo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
7.
Genes (Basel) ; 14(2)2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36833351

RESUMO

A significant variety of cell growth factors are involved in the regulation of antler growth, and the fast proliferation and differentiation of various tissue cells occur during the yearly regeneration of deer antlers. The unique development process of velvet antlers has potential application value in many fields of biomedical research. Among them, the nature of cartilage tissue and the rapid growth and development process make deer antler a model for studying cartilage tissue development or rapid repair of damage. However, the molecular mechanisms underlying the rapid growth of antlers are still not well studied. MicroRNAs are ubiquitous in animals and have a wide range of biological functions. In this study, we used high-throughput sequencing technology to analyze the miRNA expression patterns of antler growth centers at three distinct growth phases, 30, 60, and 90 days following the abscission of the antler base, in order to determine the regulatory function of miRNA on the rapid growth of antlers. Then, we identified the miRNAs that were differentially expressed at various growth stages and annotated the functions of their target genes. The results showed that 4319, 4640, and 4520 miRNAs were found in antler growth centers during the three growth periods. To further identify the essential miRNAs that could regulate fast antler development, five differentially expressed miRNAs (DEMs) were screened, and the functions of their target genes were annotated. The results of KEGG pathway annotation revealed that the target genes of the five DEMs were significantly annotated to the "Wnt signaling pathway", "PI3K-Akt signaling pathway", "MAPK signaling pathway", and "TGF-ß signaling pathway", which were associated with the rapid growth of velvet antlers. Therefore, the five chosen miRNAs, particularly ppy-miR-1, mmu-miR-200b-3p, and novel miR-94, may play crucial roles in rapid antler growth in summer.


Assuntos
Chifres de Veado , Cervos , MicroRNAs , Animais , Chifres de Veado/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Cervos/genética , Diferenciação Celular , MicroRNAs/genética
8.
iScience ; 26(3): 106158, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36843839

RESUMO

Zygotic genome activation (ZGA) is initiated once the genome chromatin state is organized in the newly formed zygote. Telomeres are specialized chromatin structures at the ends of chromosomes and are reset during early embryogenesis, while the details and significance of telomere changes in preimplantation embryos remain unclear. We demonstrated that the telomere length was shortened in the minor ZGA stage and significantly elongated in the major ZGA stage of human and mouse embryos. Expression of the ZGA pioneer factor DUX4/Dux was negatively correlated with the telomere length. ATAC sequencing data revealed that the chromatin accessibility peaks on the DUX4 promoter region (i.e., the subtelomere of chromosome 4q) were transiently augmented in human minor ZGA. Reduction of telomeric heterochromatin H3K9me3 in the telomeric region also synergistically activated DUX4 expression with p53 in human embryonic stem cells. We propose herein that telomeres regulate the expression of DUX4/Dux through chromatin remodeling and are thereby involved in ZGA.

9.
Biochem Biophys Res Commun ; 636(Pt 2): 40-47, 2022 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-36343489

RESUMO

Telomerase is activated in pluripotent stem cells and the majority of tumors and is postulated to be necessary for the acquisition of self-renewal and long-term proliferation. Placental mesenchymal stem cells (PMSCs) are very promising in regenerative medicine owing to their great capacity for self-renewal and differentiation potential. Although telomerase activity in the placenta is naturally low, it remains unclear whether telomerase activity is required for the properties of PMSCs. We herein isolated and identified a PMSC line carrying compound heterozygote variations in hTERT (DC-PMSCs) that lost telomerase activity, showed a typical surface phenotype of MSCs, and was able to differentiate into multiple cell lineages. DC-PMSCs showed accelerated telomere erosion, advanced senescence, and diminished migratory and invasive capabilities. RNA-seq identified 361 differentially expressed genes between DC-PMSCs and control groups, most of which were enriched in extracellular matrix, ECM, and related pathways. Knockdown of telomerase subunit genes in PMSCs confirmed the phenotype and attenuated the expression of extracellular matrix components and matrix metalloproteases. Our results suggest that low telomerase activity is not essential for the properties of MSCs, but that it is required for community maintenance and for the migration of PMSCs.


Assuntos
Células-Tronco Mesenquimais , Telomerase , Feminino , Gravidez , Humanos , Telomerase/genética , Telomerase/metabolismo , Placenta/metabolismo , Proliferação de Células/genética , Diferenciação Celular/genética
10.
Animals (Basel) ; 12(7)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35405922

RESUMO

The velvet antler is a unique model for cancer and regeneration research due to its periodic regeneration and rapid growth. Antler growth is mainly triggered by the growth center located in its tip, which consists of velvet skin, mesenchyme and cartilage. Among them, cartilage accounts for most of the growth center. We performed an integrative analysis of the antler cartilage transcriptome and proteome at different antler growth stages. RNA-seq results revealed 24,778 unigenes, 19,243 known protein-coding genes, and 5535 new predicted genes. Of these, 2722 were detected with differential expression patterns among 30 d, 60 d, and 90 d libraries, and 488 differentially expressed genes (DEGs) were screened at 30 d vs. 60 d and 60 d vs. 90 d but not at 30 d vs. 90 d. Proteomic data identified 1361 known proteins and 179 predicted novel proteins. Comparative analyses showed 382 differentially expressed proteins (DEPs), of which 16 had differential expression levels at 30 d vs. 60 d and 60 d vs. 90 d but not at 30 d vs. 90 d. An integrated analysis conducted for DEGs and DEPs showed that gene13546 and its coding protein protein13546 annotated in the Wnt signaling pathway may possess important bio-logical functions in rapid antler growth. This study provides in-depth characterization of candidate genes and proteins, providing further insights into the molecular mechanisms controlling antler development.

11.
Oxid Med Cell Longev ; 2020: 8396708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062148

RESUMO

Autism spectrum disorders (ASDs) are a kind of neurodevelopmental disorder with rapidly increasing morbidity. In recent years, many studies have proposed a possible link between ASD and multiple environmental as well as genetic risk factors; nevertheless, recent studies have still failed to identify the specific pathogenesis. An analysis of the literature showed that oxidative stress and redox imbalance caused by high levels of reactive oxygen species (ROS) are thought to be integral parts of ASD pathophysiology. On the one hand, this review aims to elucidate the communications between oxidative stress, as a risk factor, and ASD. As such, there is also evidence to suggest that early assessment and treatment of antioxidant status are likely to result in improved long-term prognosis by disturbing oxidative stress in the brain to avoid additional irreversible brain damage. Accordingly, we will also discuss the possibility of novel therapies regarding oxidative stress as a target according to recent literature. On the other hand, this review suggests a definite relationship between ASD and an unbalanced gastrointestinal tract (GIT) microbiota (i.e., GIT dysbiosis). A variety of studies have concluded that the intestinal microbiota influences many aspects of human health, including metabolism, the immune and nervous systems, and the mucosal barrier. Additionally, the oxidative stress and GIT dysfunction in autistic children have both been reported to be related to mitochondrial dysfunction. What is the connection between them? Moreover, specific changes in the GIT microbiota are clearly observed in most autistic children, and the related mechanisms and the connection among ASD, the GIT microbiota, and oxidative stress are also discussed, providing a theory and molecular strategies for clinical practice as well as further studies.


Assuntos
Transtorno do Espectro Autista/patologia , Microbioma Gastrointestinal , Estresse Oxidativo , Transtorno do Espectro Autista/metabolismo , Biomarcadores/sangue , Encéfalo/metabolismo , Ácidos Graxos Voláteis/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1167-1170, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798393

RESUMO

OBJECTIVE: To investigate the effect of chidamide on the killing activity of NK (Natural killer cell, NK) cells targeting K562 cells and its related mechanism. METHODS: K562 cells were pretreated with chidamide at different concentrations and cocultured with NK cells at different effect-target ratios. The killing effect of chidamide on K562 cells by NK cells, the expression of natural killer group 2 member D (NKG2D) ligands and apoptosis rate of K562 cells were detected by flow cytometry. RESULTS: The killing sensitivity of NK cells to K562 cells could be enhanced by chidamide. The expression of ULBP2 on K562 cell surface could be up-regulate, however, the expression of ULBP1 and MICA/MICB showed no statistically difference as compared with control group. Chidamide showed no obvious cytotoxicity to K562 cells. CONCLUSION: Chidamide can significantly improve killing efficiency of NK cells on K562 cells, which may be related to the up-regulation of ULBP2 expression.


Assuntos
Antígenos de Histocompatibilidade Classe I , Células Matadoras Naturais/imunologia , Aminopiridinas , Benzamidas , Proteínas Ligadas por GPI , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Células K562 , Subfamília K de Receptores Semelhantes a Lectina de Células NK
13.
Mol Genet Genomic Med ; 7(7): e00709, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31119896

RESUMO

BACKGROUND: Dyskeratosis congenita (DC) is a rare heritable bone marrow failure syndrome that is associated with telomere dysfunction, and has high genetic heterogeneity and varied features. OBJECTIVE: This study aimed to identify the underlying genetic etiology of a DC family with more severe symptoms in the younger generation and to explore the relationship between the genetic causes and the severity of DC phenotype. METHODS: Whole-exome sequencing was performed on the proband to screen the candidate causative gene. The protein structure was then predicted by SWISS-MODEL software. Telomere length (TL) assay was performed on family members along with large-scale population controls. The prenatal diagnosis (PND) was performed on the fetus of parents with secondary pregnancy. RESULTS: Novel heterozygous mutations in TERT (NM_198253.2), c.1796G>A (p.Arg599Gln), c.2839T>C (p.Ser947Pro), and c.3346G>C (p.Glu1116Gln) were identified in the proband. His TL was below the first percentile of the peers, which also appeared on the fetus with epidermal dyskeratosis through PND. The TL data of large-scale population and members of the DC family implied the accumulation of telomere erosion in successive generations in this family. CONCLUSIONS: Our study identified three clinical pathologic TERT mutations and implied that telomere erosion might be accumulated through successive generations, contributing to the severity of DC in the younger generation.


Assuntos
Disceratose Congênita/patologia , Telomerase/genética , Telômero/genética , Pré-Escolar , Disceratose Congênita/genética , Heterozigoto , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Diagnóstico Pré-Natal , Estrutura Terciária de Proteína , Telomerase/química , Homeostase do Telômero , Sequenciamento do Exoma
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(2): 563-568, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29665933

RESUMO

OBJECTIVE: To investigate the effect of microRNA-99a-5p (miR-99a-5p) on differentiation ability of human bone marrow mesenchymal stem cells (BM-MSC). METHODS: BM-MSC was cultured and then transfected with miR-99a-5p mimics or inhibitors. The transfection efficiency was detected by real-time quantitative PCR. The effects of miR-99a-5p on the adipogenic and osteogenic differentiation ability of BM-MSC were detected by differentiation experiment. RESULTS: As compared with the negative control group, the expression of miR-99a-5p was significantly up-regulated after transfection with miR-99a-5p mimics(P<0.001), the expression of miR-99a-5p was down-regulated after transfection with miR-99a-5p inhibitor (P<0.001). In osteogenic differentiation experiments, the miR-99a-5p overexpression could promote the osteogenic differentiation, while the downregulation of miR-99a-5p expression inhibited the osteogenic differentiation. The same results were obtained by semi-quantitative detection through spectrophotometry. In the adipogenic differentiation test, transfection of miR-99a-5p mimics or inhibitors had no significant effect on the adipogenic differentiation of BM-MSC. CONCLUSION: Overexpression of miR-99a-5p can promote the osteogenic differentiation of BM-MSC, but no significant effects are observed in the adipogenic differentiation.


Assuntos
Células-Tronco Mesenquimais , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Humanos , MicroRNAs , Osteogênese
15.
Mol Brain ; 9(1): 63, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27267759

RESUMO

BACKGROUND: Endothelial cell (EC) released microvesicles (EMVs) can affect various target cells by transferring carried genetic information. Astrocytes are the main components of the blood brain barrier (BBB) structure in the brain and participate in regulating BBB integrity and blood flow. The interactions between ECs and astrocytes are essential for BBB integrity in homeostasis and pathological conditions. Here, we studied the effects of human brain microvascular ECs released EMVs on astrocyte functions. Additionally, we investigated the effects of EMVs treated astrocytes on regulating BBB function and cerebral ischemic damage. RESULTS: EMVs prepared from ECs cultured in normal condition (n-EMVs) or oxygen and glucose deprivation (OGD-EMVs) condition had diverse effects on astrocytes. The n-EMVs promoted, while the OGD-EMVs inhibited the proliferation of astrocytes via regulating PI3K/Akt pathway. Glial fibrillary acidic protein (GFAP) expression (marker of astrocyte activation) was up-regulated by n-EMVs, while down-regulated by OGD-EMVs. Meanwhile, n-EMVs inhibited but OGD-EMVs promoted the apoptosis of astrocytes accompanied by up/down-regulating the expression of Caspase-9 and Bcl-2. In the BBB model of ECs-astrocytes co-culture, the n-EMVs, conversely to OGD-EMVs, decreased the permeability of BBB accompanied with up-regulation of zonula occudens-1(ZO-1) and Claudin-5. In a transient cerebral ischemia mouse model, n-EMVs ameliorated, while OGD-EMVs aggravated, BBB disruption, local cerebral blood flow (CBF) reduction, infarct volume and neurological deficit score. CONCLUSIONS: Our data suggest that EMVs diversely modulate astrocyte functions, BBB integrity and CBF, and could serve as a novel therapeutic target for ischemic stroke.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/fisiopatologia , Isquemia Encefálica/fisiopatologia , Micropartículas Derivadas de Células/metabolismo , Circulação Cerebrovascular , Células Endoteliais/metabolismo , Microvasos/patologia , Acidente Vascular Cerebral/fisiopatologia , Animais , Apoptose , Barreira Hematoencefálica/patologia , Isquemia Encefálica/complicações , Isquemia Encefálica/patologia , Caspase 9/metabolismo , Claudina-5/metabolismo , Citometria de Fluxo , Glucose/deficiência , Humanos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Masculino , Camundongos Endogâmicos C57BL , Oxigênio , Permeabilidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia , Proteína da Zônula de Oclusão-1/metabolismo
16.
J Stroke Cerebrovasc Dis ; 24(10): 2313-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26169549

RESUMO

BACKGROUND: Platelet activation and aggregation are critical in the pathogenesis of acute ischemic stroke (AIS). Circulating platelet microparticles (PMPs) and platelet parameters are biologic markers of platelet function in AIS patients; however, their associations with stroke subtypes and infarct volume remain unknown. METHODS: We recruited 112 AIS patients including large-artery atherosclerosis (LAA) and small-artery occlusion [SAO] subtypes and 35 controls in this study. Blood samples were collected at admission and after antiplatelet therapy. The levels of circulating PMPs and platelet parameters (mean platelet volume [MPV], platelet count, plateletocrit, and platelet distribution width) were determined by flow cytometry and hematology analysis, respectively. Infarct volume was examined at admission by magnetic resonance imaging. RESULTS: (1) The levels of circulating PMPs and MPV were significantly elevated in AIS patients compared with healthy controls; (2) the level of circulating PMPs, but not platelet parameters, was decreased after antiplatelet therapy in AIS patients; (3) the infarct volume in LAA subtype was larger than that in SAO subtype. Notably, circulating PMP level was positively correlated with the infarct volume in LAA subtype. No association with infarct volume in either AIS subtype was observed for platelet parameters; and (4) according to the regression analysis, circulating PMP was an independent risk factor for the infarct volume in pooled AIS patients after adjustments of other impact factors (hypertension and diabetes). CONCLUSIONS: Our results suggest that circulating PMP level is associated with cerebral injury of AIS, which offers a novel evaluation parameter for AIS patients.


Assuntos
Plaquetas , Infarto Encefálico/sangue , Contagem de Plaquetas , Acidente Vascular Cerebral/sangue , Idoso , Plaquetas/patologia , Infarto Encefálico/etiologia , Infarto Encefálico/patologia , Isquemia Encefálica/complicações , Feminino , Citometria de Fluxo , Humanos , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia
17.
J Cell Biochem ; 116(12): 2870-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26012521

RESUMO

The microRNA-155 (miR155) regulates various functions of cells. Dysfunction or injury of endothelial cells (ECs) plays an important role in the pathogenesis of various vascular diseases. In this study, we investigated the role and potential mechanisms of miR155 in human brain microvessel endothelial cells (HBMECs) under physiological and pathological conditions. We detected the effects of miR155 silencing on ROS production, NO generation, apoptosis and functions of HBMECs at basal and in response to oxidized low density lipoprotein (ox-LDL). Western blot and q-PCR were used for analyzing the gene expression of epidermal growth factor receptor (EGFR)/extracellular regulated protein kinases (ERK)/p38 mitogen-activated protein kinase (p38 MAPK), phosphatidylinositol-3-kinase (PI3K) and serine/threonine kinase(Akt), activated caspase-3, and intercellular adhesion molecule-1 (ICAM-1). Results showed that under both basal and challenge situations: (1) Silencing of miR155 decreased apoptosis and reactive oxygen species (ROS) production of HBMECs, whereas, promoted nitric oxide (NO) generation. (2) Silencing of miR155 increased the proliferation, migration, and tube formation ability of HBMECs, while decreased cell adhesion ability. (3) Gene expression analyses showed that EGFR/ERK/p38 MAPK and PI3K/Akt were increased and that activated caspase-3 and ICAM-1 mRNA were decreased after knockdown of miR155. In conclusion, knockdown of miR155 could modulate ROS production, NO generation, apoptosis and function of HBMECs via regulating diverse gene expression, such as caspase-3, ICAM-1 and EGFR/ERK/p38 MAPK and PI3K/Akt pathways.


Assuntos
Encéfalo/metabolismo , MicroRNAs/genética , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Apoptose/genética , Encéfalo/patologia , Caspase 3/biossíntese , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Regulação da Expressão Gênica , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Lipoproteínas LDL/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Microvasos/metabolismo , Microvasos/patologia , Óxido Nítrico/biossíntese , Proteínas Proto-Oncogênicas c-akt/biossíntese , Transdução de Sinais/genética , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese
18.
Artigo em Inglês | MEDLINE | ID: mdl-23767649

RESUMO

We study the dynamics of dipolar gas in deep lattices described by a nonlocal nonlinear discrete Gross-Pitaevskii equation. The stabilities and the propagation properties of traveling plane waves in the system with defects are discussed in detail. For a clean lattice, both energetic and dynamical stabilities of the traveling plane waves are studied. It is shown that the system with attractive local interaction can preserve the stabilities, i.e., the dipoles can stabilize the gas because of repulsive nonlocal dipole-dipole interactions. For a lattice with defects, within a two-mode approximation, the propagation properties of traveling plane waves in the system map onto a nonrigid pendulum Hamiltonian with quasimomentum-dependent nonlinearity (induced by the nonlocal interactions). Competition between defects, quasimomentum of the gas, and nonlocal interactions determines the propagation properties of the traveling plane waves. Critical conditions for crossing from a superfluid regime with propagation preserved to a normal regime with defect-induced damping are obtained analytically and confirmed numerically. In particular, the critical conditions for supporting the superfluidity strongly depend on the defect type and the quasimomentum of the plane waves. The nonlocal interaction can significantly enhance the superfluidity of the system.


Assuntos
Gases/química , Microfluídica/métodos , Modelos Químicos , Modelos Moleculares , Dinâmica não Linear , Simulação por Computador
19.
Pharmazie ; 67(3): 229-32, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22530304

RESUMO

Current efforts had been made to undertake a three-dimensional (3-D) reverse transfection of bone marrow-derived mesenchymal stem cells (BM-MSCs) in PLGA scaffolds. As a kind of multipotent stem cells, BM-MSCs show great potential and tremendous capacity in the gene transfection field and PLGA 3-D scaffold has been shown to be a biomaterial that provides structural support to cells proliferation and tissue engineering. The objective of this study was to assess the transfection efficiency of BM-MSCs with a 3-D reverse transfection method by using PLGA scaffold and observe the SEM photographs of BM-MSCs cultured on PLGA scaffold. BM-MSCs were cultured in 3-D PLGA scaffold which was incorporated with pullulan-spermine/pGL3. It was shown that the gene expression duration of BM-MSCs transfected using 3D reverse method with pullulan-spermine/DNA in the presence of serum maintained 12 days at high levels as compared with the plasmid DNA in medium, and scanning electronic microscopy (SEM) photographs of BM-MSCs cultured on PLGA scaffold exhibited robust cell attachment and viability when cultured in PLGA scaffold in vitro. This study demonstrates that the 3-D reverse transfection method of BM-MSCs using PLGA scaffold could achieve long gene expression in a relatively high level, therefore this transfection system is promising in gene transfection and tissue engineering.


Assuntos
DNA/biossíntese , DNA/química , Ácido Láctico/química , Células-Tronco Mesenquimais/metabolismo , Plasmídeos/química , Ácido Poliglicólico/química , Animais , Adesão Celular , Células Cultivadas , Excipientes , Glucanos/química , Masculino , Microscopia Eletrônica de Varredura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Espermina/química , Transfecção/métodos
20.
Biotechnol Appl Biochem ; 59(3): 163-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586825

RESUMO

This study evaluated the potential of utilizing transfected pTGFß-1 gene-engineered rat mesenchymal stem cells (MSCs) using nonviral vector to promote cartilage regeneration. Pullulan-spermine was used as the nonviral gene vector and gelatin sponge was used as the scaffold. MSCs were engineered with TGF-ß1 gene with either the three-dimensional (3D) reverse transfection system or the two-dimensional (2D) conventional transfection system. For the 3D reverse transfection system, pullulan-spermine/pTGF-ß1 gene complexes were immobilized to the gelatin sponge, followed by the seeding of MSCs. Pullulan-spermine/pTGF-ß1 gene complexes were delivered to MSCs cultured in the plate to perform the 2D conventional transfection system, and then MSCs were seeded to the gelatin sponge. Then, TGF-ß1 gene-transfected MSC seeded gelatin sponge was implanted to the full-thickness cartilage defect. Compared with the control group, both groups of TGF-ß1 gene-engineered MSCs improved cartilage regeneration through optical observation and histology staining. So, with pullulan-spermine as the nonviral vector, TGF-ß1-gene engineered MSCs can induce cartilage regeneration in vivo.


Assuntos
Cartilagem/citologia , Vetores Genéticos/genética , Transplante de Células-Tronco Mesenquimais , Regeneração/genética , Fator de Crescimento Transformador beta1/genética , Animais , Cartilagem/metabolismo , Técnicas de Transferência de Genes , Glucanos/genética , Glucanos/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley , Espermina/metabolismo
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