75 resultados para gene expression data
Resumo:
Acute psychosocial stress stimulates transient increases in circulating pro-inflammatory plasma cytokines, but little is known about stress effects on anti-inflammatory cytokines or underlying mechanisms. We investigated the stress kinetics and interrelations of pro- and anti-inflammatory measures on the transcriptional and protein level. Forty-five healthy men were randomly assigned to either a stress or control group. While the stress group underwent an acute psychosocial stress task, the second group participated in a non-stress control condition. We repeatedly measured before and up to 120min after stress DNA binding activity of the pro-inflammatory transcription factor NF-κB (NF-κB-BA) in peripheral blood mononuclear cells, whole-blood mRNA levels of NF-κB, its inhibitor IκBα, and of the pro-inflammatory cytokines interleukin (IL)-1ß and IL-6, and the anti-inflammatory cytokine IL-10. We also repeatedly measured plasma levels of IL-1ß, IL-6, and IL-10. Compared to non-stress, acute stress induced significant and rapid increases in NF-κB-BA and delayed increases in plasma IL-6 and mRNA of IL-1ß, IL-6, and IκBα (p's<.045). In the stress group, significant increases over time were also observed for NF-κB mRNA and plasma IL-1ß and IL-10 (p's<.055). NF-κB-BA correlated significantly with mRNA of IL-1β (r=.52, p=.002), NF-κB (r=.48, p=.004), and IκBα (r=.42, p=.013), and marginally with IL-6 mRNA (r=.31, p=.11). Plasma cytokines did not relate to NF-κB-BA or mRNA levels of the respective cytokines. Our data suggest that stress induces increases in NF-κB-BA that relate to subsequent mRNA expression of pro-inflammatory, but not anti-inflammatory cytokines, and of regulatory-cytoplasmic-proteins. The stress-induced increases in plasma cytokines do not seem to derive from de novo synthesis in circulating blood cells.
Resumo:
Background The enoyl-acyl carrier protein (ACP) reductase enzyme (FabI) is the target for a series of antimicrobial agents including novel compounds in clinical trial and the biocide triclosan. Mutations in fabI and heterodiploidy for fabI have been shown to confer resistance in S. aureus strains in a previous study. Here we further determined the fabI upstream sequence of a selection of these strains and the gene expression levels in strains with promoter region mutations. Results Mutations in the fabI promoter were found in 18% of triclosan resistant clinical isolates, regardless the previously identified molecular mechanism conferring resistance. Although not significant, a higher rate of promoter mutations were found in strains without previously described mechanisms of resistance. Some of the mutations identified in the clinical isolates were also detected in a series of laboratory mutants. Microarray analysis of selected laboratory mutants with fabI promoter region mutations, grown in the absence of triclosan, revealed increased fabI expression in three out of four tested strains. In two of these strains, only few genes other than fabI were upregulated. Consistently with these data, whole genome sequencing of in vitro selected mutants identified only few mutations except the upstream and coding regions of fabI, with the promoter mutation as the most probable cause of fabI overexpression. Importantly the gene expression profiling of clinical isolates containing similar mutations in the fabI promoter also showed, when compared to unrelated non-mutated isolates, a significant up-regulation of fabI. Conclusions In conclusion, we have demonstrated the presence of C34T, T109G, and A101C mutations in the fabI promoter region of strains with fabI up-regulation, both in clinical isolates and/or laboratory mutants. These data provide further observations linking mutations upstream fabI with up-regulated expression of the fabI gene.
Resumo:
PURPOSE Autologous bone is used for augmentation in the course of oral implant placement. Bone grafts release paracrine signals that can modulate mesenchymal cell differentiation in vitro. The detailed genetic response of the bone-derived fibroblasts to these paracrine signals has remained elusive. Paracrine signals accumulate in bone-conditioned medium (BCM) prepared from porcine cortical bone chips. MATERIALS AND METHODS In this study, bone-derived fibroblasts were exposed to BCM followed by a whole genome expression profiling and downstream quantitative reverse transciptase polymerase chain reaction of the most strongly regulated genes. RESULTS The data show that ADM, IL11, IL33, NOX4, PRG4, and PTX3 were differentially expressed in response to BCM in bone-derived fibroblasts. The transforming growth factor beta (TGF-β) receptor 1 antagonist SB431542 blocked the effect of BCM on the expression of the gene panel, except for IL33. CONCLUSION These in vitro results extend existing evidence that cortical bone chips release paracrine signals that provoke a robust genetic response in mesenchymal cells that is not exclusively mediated via the TGF-β receptor. The present data provide further insights into the process of graft consolidation.
Resumo:
Alveolar echinococcosis (AE) is a severe chronic hepatic parasitic disease currently emerging in central and eastern Europe. Untreated AE presents a high mortality (>90%) due to a severe hepatic destruction as a result of parasitic metacestode proliferation which behaves like a malignant tumor. Despite this severe course and outcome of disease, the genetic program that regulates the host response leading to organ damage as a consequence of hepatic alveolar echinococcosis is largely unknown.
Resumo:
Pheochromocytomas are rare neoplasias of neural crest origin arising from chromaffin cells of the adrenal medulla and sympathetic ganglia (extra-adrenal pheochromocytoma). Pheochromocytoma that develop in rats homozygous for a loss-of-function mutation in p27Kip1 (MENX syndrome) show a clear progression from hyperplasia to tumor, offering the possibility to gain insight into tumor pathobiology. We compared the gene-expression signatures of both adrenomedullary hyperplasia and pheochromocytoma with normal rat adrenal medulla. Hyperplasia and tumor show very similar transcriptome profiles, indicating early determination of the tumorigenic signature. Overrepresentation of developmentally regulated neural genes was a feature of the rat lesions. Quantitative RT-PCR validated the up-regulation of 11 genes, including some involved in neural development: Cdkn2a, Cdkn2c, Neurod1, Gal, Bmp7, and Phox2a. Overexpression of these genes precedes histological changes in affected adrenal glands. Their presence at early stages of tumorigenesis indicates they are not acquired during progression and may be a result of the lack of functional p27Kip1. Adrenal and extra-adrenal pheochromocytoma development clearly follows diverged molecular pathways in MENX rats. To correlate these findings to human pheochromocytoma, we studied nine genes overexpressed in the rat lesions in 46 sporadic and familial human pheochromocytomas. The expression of GAL, DGKH, BMP7, PHOX2A, L1CAM, TCTE1, EBF3, SOX4, and HASH1 was up-regulated, although with different frequencies. Immunohistochemical staining detected high L1CAM expression selectively in 27 human pheochromocytomas but not in 140 nonchromaffin neuroendocrine tumors. These studies reveal clues to the molecular pathways involved in rat and human pheochromocytoma and identify previously unexplored biomarkers for clinical use.
Resumo:
OBJECTIVES: To compare the gene expression profile of osseointegration associated with a moderately rough and a chemically modified hydrophilic moderately rough surface in a human model. MATERIAL AND METHODS: Eighteen solid screw-type cylindrical titanium implants, 4 mm long and 2.8 mm wide, with either a moderately rough (SLA) or a chemically modified moderately rough (SLActive) surface were surgically inserted in the retromolar area of nine human volunteers. The devices were removed using a trephine following 4, 7 and 14 days of healing. The tissue surrounding the implant was harvested, total RNA was extracted and microarray analysis was carried out to identify the differences in the transcriptome between the SLA and SLActive surfaces at days 4, 7 and 14. RESULTS: There were no functionally relevant gene ontology categories that were over-represented in the list of genes that were differentially expressed at day 4. However, by day 7, osteogenesis- and angiogenesis-associated gene expression were up-regulated on the SLActive surface. Osteogenesis and angiogenesis appeared to be regulated by BMP and VEGF signalling, respectively. By day 14, VEGF signalling remains up-regulated on the SLActive surface, while BMP signalling was up-regulated on the SLA surface in what appeared to be a delayed compensatory response. Furthermore, neurogenesis was a prominent biological process within the list of differentially expressed genes, and it was influenced by both surfaces. CONCLUSIONS: Compared with SLA, SLActive exerts a pro-osteogenic and pro-angiogenic influence on gene expression at day 7 following implant insertion, which may be responsible for the superior osseointegrative properties of this surface.
Resumo:
Boron is one of the trace elements in the human body which plays an important role in bone growth. Porous mesopore bioactive glass (MBG) scaffolds are proposed as potential bone regeneration materials due to their excellent bioactivity and drug-delivery ability. The aims of the present study were to develop boron-containing MBG (B-MBG) scaffolds by sol-gel method and to evaluate the effect of boron on the physiochemistry of B-MBG scaffolds and the response of osteoblasts to these scaffolds. Furthermore, the effect of dexamethasone (DEX) delivery in B-MBG scaffold system was investigated on the proliferation, differentiation and bone-related gene expression of osteoblasts. The composition, microstructure and mesopore properties (specific surface area, nano-pore volume and nano-pore distribution) of B-MBG scaffolds have been characterized. The effect of boron contents and large-pore porosity on the loading and release of DEX in B-MBG scaffolds were also investigated. The results have shown that the incorporation of boron into MBG scaffolds slightly decreases the specific surface area and pore volume, but maintains well-ordered mesopore structure and high surface area and nano-pore volume compared to non-mesopore bioactive glass. Boron contents in MBG scaffolds did not influence the nano-pore size distribution or the loading and release of DEX. B-MBG scaffolds have the ability to maintain a sustained release of DEX in a long-term span. Incorporating boron into MBG glass scaffolds led to a controllable release of boron ions and significantly improved the proliferation and bone-related gene expression (Col I and Runx2) of osteoblasts. Furthermore, the sustained release of DEX from B-MBG scaffolds significantly enhanced alkaline phosphatase (ALP) activity and gene expressions (Col I, Runx2, ALP and BSP) of osteoblasts. These results suggest that boron plays an important role in enhancing osteoblast proliferation in B-MBG scaffold system and DEX-loaded B-MBG scaffolds show great potential as a release system to enhance osteogenic property for bone tissue engineering application.
Resumo:
Gene therapy of the heart has been attempted in a number of clinical trials with the injection of naked DNA, although quantitative information on myocellular transfection rates is not available. The present study aimed to quantify the efficacy of electropulsing protocols that differ in pulse duration and number to stimulate transfection of cardiomyocytes and to determine the impact on myocardial integrity.
Resumo:
To analyze the vascularization of the endometrium via hysteroscopy and to assess its correlation with angiogenic factor gene expression and embryo implantation rate.
Resumo:
Background Inappropriate cross talk between mammals and their gut microbiota may trigger intestinal inflammation and drive extra-intestinal immune-mediated diseases. Epithelial cells constitute the interface between gut microbiota and host tissue, and may regulate host responses to commensal enteric bacteria. Gnotobiotic animals represent a powerful approach to study bacterial-host interaction but are not readily accessible to the wide scientific community. We aimed at refining a protocol that in a robust manner would deplete the cultivable intestinal microbiota of conventionally raised mice and that would prove to have significant biologic validity. Methodology/Principal Findings Previously published protocols for depleting mice of their intestinal microbiota by administering broad-spectrum antibiotics in drinking water were difficult to reproduce. We show that twice daily delivery of antibiotics by gavage depleted mice of their cultivable fecal microbiota and reduced the fecal bacterial DNA load by 400 fold while ensuring the animals' health. Mice subjected to the protocol for 17 days displayed enlarged ceca, reduced Peyer's patches and small spleens. Antibiotic treatment significantly reduced the expression of antimicrobial factors to a level similar to that of germ-free mice and altered the expression of 517 genes in total in the colonic epithelium. Genes involved in cell cycle were significantly altered concomitant with reduced epithelial proliferative activity in situ assessed by Ki-67 expression, suggesting that commensal microbiota drives cellular proliferation in colonic epithelium. Conclusion We present a robust protocol for depleting conventionally raised mice of their cultivatable intestinal microbiota with antibiotics by gavage and show that the biological effect of this depletion phenocopies physiological characteristics of germ-free mice.
Resumo:
Objective Increasing plasma glucose levels are associated with increasing risk of vascular disease. We tested the hypothesis that there is a glycaemia-mediated impairment of reverse cholesterol transport (RCT). We studied the influence of plasma glucose on expression and function of a key mediator in RCT, the ATP binding cassette transporter-A1 (ABCA1) and expression of its regulators, liver X receptor-α (LXRα) and peroxisome proliferator-activated receptor–γ (PPARγ). Methods and Results Leukocyte ABCA1, LXRα and PPARγ expression was measured by polymerase chain reaction in 63 men with varying degrees of glucose homeostasis. ABCA1 protein concentrations were measured in leukocytes. In a sub-group of 25 men, ABCA1 function was quantified as apolipoprotein-A1-mediated cholesterol efflux from 2–3 week cultured skin fibroblasts. Leukocyte ABCA1 expression correlated negatively with circulating HbA1c and glucose (rho = −0.41, p<0.001; rho = −0.34, p = 0.006 respectively) and was reduced in Type 2 diabetes (T2DM) (p = 0.03). Leukocyte ABCA1 protein was lower in T2DM (p = 0.03) and positively associated with plasma HDL cholesterol (HDL-C) (rho = 0.34, p = 0.02). Apolipoprotein-A1-mediated cholesterol efflux correlated negatively with fasting glucose (rho = −0.50, p = 0.01) and positively with HDL-C (rho = 0.41, p = 0.02). It was reduced in T2DM compared with controls (p = 0.04). These relationships were independent of LXRα and PPARγ expression. Conclusions ABCA1 expression and protein concentrations in leukocytes, as well as function in cultured skin fibroblasts, are reduced in T2DM. ABCA1 protein concentration and function are associated with HDL-C levels. These findings indicate a glycaemia- related, persistent disruption of a key component of RCT.
Resumo:
CD8 T cells play a key role in mediating protective immunity against selected pathogens after vaccination. Understanding the mechanism of this protection is dependent upon definition of the heterogeneity and complexity of cellular immune responses generated by different vaccines. Here, we identify previously unrecognized subsets of CD8 T cells based upon analysis of gene-expression patterns within single cells and show that they are differentially induced by different vaccines. Three prime-boost vector combinations encoding HIV Env stimulated antigen-specific CD8 T-cell populations of similar magnitude, phenotype, and functionality. Remarkably, however, analysis of single-cell gene-expression profiles enabled discrimination of a majority of central memory (CM) and effector memory (EM) CD8 T cells elicited by the three vaccines. Subsets of T cells could be defined based on their expression of Eomes, Cxcr3, and Ccr7, or Klrk1, Klrg1, and Ccr5 in CM and EM cells, respectively. Of CM cells elicited by DNA prime-recombinant adenoviral (rAd) boost vectors, 67% were Eomes(-) Ccr7(+) Cxcr3(-), in contrast to only 7% and 2% stimulated by rAd5-rAd5 or rAd-LCMV, respectively. Of EM cells elicited by DNA-rAd, 74% were Klrk1(-) Klrg1(-)Ccr5(-) compared with only 26% and 20% for rAd5-rAd5 or rAd5-LCMV. Definition by single-cell gene profiling of specific CM and EM CD8 T-cell subsets that are differentially induced by different gene-based vaccines will facilitate the design and evaluation of vaccines, as well as enable our understanding of mechanisms of protective immunity.
Resumo:
Dairy cows with high and low plasma non-esterified fatty acid (NEFA) concentrations in early lactation were compared for plasma parameters and mRNA expression of genes in liver and subcutaneous adipose tissue. The study involved 16 multiparous dairy cows with a plasma NEFA concentration of >500 mumol/l [n = 8, high NEFA (HNEFA)] and <140 mumol/l [n = 8, low NEFA (LNEFA)] in the first week post-partum (pp). Blood samples, adipose and liver tissues were collected on day 1 (+1d) and at week 3 pp (+3wk). Blood plasma was assayed for concentrations of metabolites and hormones. Subcutaneous adipose and liver tissues were analysed for mRNA abundance by real-time qRT-PCR encoding parameters related to lipid metabolism. Results showed that mean daily milk yield and milk fat quantity were higher in HNEFA than in LNEFA cows (p < 0.01), and the NEB was more negative in HNEFA than in LNEFA in +3wk too (p < 0.05). HNEFA cows had slightly lower (p < 0.1) insulin concentrations than LNEFA cows across the study period, and the body condition score decreased more from +1d to +3wk in HNEFA than in LNEFA (p = 0.09). The mRNA abundance of genes in the liver related to fatty acid oxidation (carnitine palmitoyltransferase 2 and very long chain acyl-coenzyme A dehydrogenase) and ketogenesis (3-hydroxy-3-methylglutaryl-coenzyme A synthase 2) were lower in HNEFA than in LNEFA cows. No differences between the two groups were observed for mRNA expression of genes in adipose tissue. The number of calculated significant correlation coefficients (moderately strong) between parameters in the liver and in adipose tissue was nearly similar on +1d, and higher for HNEFA compared with LNEFA cows in +3wk. In conclusion, dairy cows with high compared with low plasma NEFA concentrations in early lactation show differentially synchronized mRNA expression of genes in adipose tissue and liver in +3wk that suggests a different orchestrated homeorhetic regulation of lipid metabolism.
Resumo:
Mechanical ventilation (MV) is life-saving but potentially harmful for lungs of premature infants. So far, animal models dealt with the acute impact of MV on immature lungs, but less with its delayed effects. We used a newborn rodent model including non-surgical and therefore reversible intubation with moderate ventilation and hypothesized that there might be distinct gene expression patterns after a ventilation-free recovery period compared to acute effects directly after MV. Newborn rat pups were subjected to 8 hr of MV with 60% oxygen (O(2)), 24 hr after injection of lipopolysaccharide (LPS), intended to create a low inflammatory background as often recognized in preterm infants. Animals were separated in controls (CTRL), LPS injection (LPS), or full intervention with LPS and MV with 60% O(2) (LPS + MV + O(2)). Lungs were recovered either directly following (T:0 hr) or 48 hr after MV (T:48 hr). Histologically, signs of ventilator-induced lung injury (VILI) were observed in LPS + MV + O(2) lungs at T:0 hr, while changes appeared similar to those known from patients with chronic lung disease (CLD) with fewer albeit larger gas exchange units, at T:48 hr. At T:0 hr, LPS + MV + O(2) increased gene expression of pro-inflammatory MIP-2. In parallel anti-inflammatory IL-1Ra gene expression was increased in LPS and LPS + MV + O(2) groups. At T:48 hr, pro- and anti-inflammatory genes had returned to their basal expression. MMP-2 gene expression was decreased in LPS and LPS + MV + O(2) groups at T:0 hr, but no longer at T:48 hr. MMP-9 gene expression levels were unchanged directly after MV. However, at T:48 hr, gene and protein expression increased in LPS + MV + O(2) group. In conclusion, this study demonstrates the feasibility of delayed outcome measurements after a ventilation-free period in newborn rats and may help to further understand the time-course of molecular changes following MV. The differences obtained from the two time points could be interpreted as an initial transitory increase of inflammation and a delayed impact of the intervention on structure-related genes.