scholarly journals Transcriptomic Analysis of Human Astrocytes In Vitro Reveals Hypoxia-Induced Mitochondrial Dysfunction, Modulation of Metabolism, and Dysregulation of the Immune Response

2020 ◽  
Vol 21 (21) ◽  
pp. 8028 ◽  
Author(s):  
Scott P. Allen ◽  
Rajpinder Singh Seehra ◽  
Paul R. Heath ◽  
Benjamin P. C. Hall ◽  
Jessica Bates ◽  
...  
Keyword(s):  
Immune Response ◽  
Oxygen Availability ◽  
Differentially Expressed ◽  
Glycolytic Flux ◽  
Hypoxic Conditions ◽  
Human Astrocytes ◽  
Glial Function ◽  
The Central Nervous System ◽  
Induced Changes

Hypoxia is a feature of neurodegenerative diseases, and can both directly and indirectly impact on neuronal function through modulation of glial function. Astrocytes play a key role in regulating homeostasis within the central nervous system, and mediate hypoxia-induced changes in response to reduced oxygen availability. The current study performed a detailed characterization of hypoxia-induced changes in the transcriptomic profile of astrocytes in vitro. Human astrocytes were cultured under normoxic (5% CO2, 95% air) or hypoxic conditions (1% O2, 5% CO2, 94% N2) for 24 h, and the gene expression profile assessed by microarray analysis. In response to hypoxia 4904 genes were significantly differentially expressed (1306 upregulated and 3598 downregulated, FC ≥ 2 and p ≤ 0.05). Analysis of the significant differentially expressed transcripts identified an increase in immune response pathways, and dysregulation of signalling pathways, including HIF-1 (p = 0.002), and metabolism, including glycolysis (p = 0.006). To assess whether the hypoxia-induced metabolic gene changes observed affected metabolism at a functional level, both the glycolytic and mitochondrial flux were measured using an XF bioanalyser. In support of the transcriptomic data, under physiological conditions hypoxia significantly reduced mitochondrial respiratory flux (p = 0.0001) but increased basal glycolytic flux (p = 0.0313). However, when metabolically stressed, hypoxia reduced mitochondrial spare respiratory capacity (p = 0.0485) and both glycolytic capacity (p = 0.0001) and glycolytic reserve (p < 0.0001). In summary, the current findings detail hypoxia-induced changes in the astrocyte transcriptome in vitro, identifying potential targets for modifying the astrocyte response to reduced oxygen availability in pathological conditions associated with ischaemia/hypoxia, including manipulation of mitochondrial function, metabolism, and the immune response.

Hypoxia-induced changes in shivering and body temperature

1987 ◽  
Vol 62 (6) ◽  
pp. 2477-2484 ◽  
Author(s):  
H. Gautier ◽  
M. Bonora ◽  
S. A. Schultz ◽  
J. E. Remmers
Keyword(s):  
Central Nervous System ◽  
Body Temperature ◽  
Room Temperature ◽  
Co2 Concentration ◽  
Hypoxic Conditions ◽  
O2 Concentration ◽  
The Central Nervous System ◽  
Induced Changes ◽  
Maintain Body Temperature ◽  
Ambient Hypoxia

Experiments were carried out on conscious cats to evaluate the general characteristics and modes of action of hypoxia on thermoregulation during cold stress. Intact and carotid-denervated (CD) conscious cats were exposed to ambient hypoxia (low inspired O2 fraction) or CO hypoxia in prevailing laboratory (23–25 degrees C) or cold (5–8 degrees C) environments. In the cold, both groups promptly decreased shivering and body temperature when exposed to either type of hypoxia. Small increases in CO2 concentration reinstituted shivering in both groups. At the same inspired concentration of O2, CD animals decreased shivering and body temperature more than intact cats. While this difference resulted, in part, from a lower alveolar PO2 in CD cats, a difference between intact and CD cats was apparent when the two groups were compared at the same alveolar PO2. During more prolonged hypoxia (45 min), shivering returned but did not reach normoxic levels, and body temperature tended to stabilize at a hypothermic value. Exposure to various levels of hypoxia produced graded suppression of shivering, with the result that the change in body temperature varied directly with inspired O2 concentration. Hypoxia appears to act on the central nervous system to suppress shivering and sinus nerve afferents appear to counteract this direct effect of hypoxia. In intact cats, this counteraction appears to be sufficient to maintain body temperature under hypoxic conditions at room temperature but not in the cold.

scholarly journals Suppressed expression of genes involved in transcription and translation in in vitro compared with in vivo cultured bovine embryos

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 651-660 ◽  
Author(s):  
D Corcoran ◽  
T Fair ◽  
S Park ◽  
D Rizos ◽  
O V Patel ◽  
...  
Keyword(s):  
Expressed Sequence Tags ◽  
Differentially Expressed ◽  
Bovine Embryos ◽  
Quantitative Real Time Pcr ◽  
Expression Of Genes ◽  
Mrna Transcripts ◽  
Induced Changes ◽  
Expressed Sequence

In vivo-derived bovine embryos are of higher quality than those derivedin vitro. Many of the differences in quality can be related to culture environment-induced changes in mRNA abundance. The aim of this study was to identify a range of mRNA transcripts that are differentially expressed between bovine blastocysts derived fromin vitroversusin vivoculture. Microarray (BOTL5) comparison betweenin vivo- andin vitro-cultured bovine blastocysts identified 384 genes and expressed sequence tags (ESTs) that were differentially expressed; 85% of these were down-regulated inin vitrocultured blastocysts, showing a much reduced overall level of mRNA expression inin vitro- compared within vivo-cultured blastocysts. Relative expression of 16 out of 23 (70%) differentially expressed genes (according toPvalue) were verified in new pools ofin vivo- andin vitro-cultured blastocysts, using quantitative real-time PCR. Most (10 out of 16) are involved in transcription and translation events, suggesting that the reason whyin vitro-derived embryos are of inferior quality compared within vivo-derived embryos is due to a deficiency of the machinery associated with transcription and translation.

Regulatory factors controlling transcription of Saccharomyces cerevisiae IXR1 by oxygen levels: a model of transcriptional adaptation from aerobiosis to hypoxia implicating ROX1 and IXR1 cross-regulation

2009 ◽  
Vol 425 (1) ◽  
pp. 235-243 ◽  
Author(s):  
Raquel  Castro-Prego ◽  
Mónica Lamas-Maceiras ◽  
Pilar Soengas ◽  
Isabel Carneiro ◽  
Isabel González-Siso ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Oxygen Availability ◽  
Mrna Levels ◽  
Mobility Shift ◽  
Hypoxic Conditions ◽  
Cross Links ◽  
Mobility Shift Assay ◽  
Transcriptional Adaptation

Ixr1p from Saccharomyces cerevisiae has been previously studied because it binds to DNA containing intrastrand cross-links formed by the anticancer drug cisplatin. Ixr1p is also a transcriptional regulator of anaerobic/hypoxic genes, such as SRP1/TIR1, which encodes a stress-response cell wall manoprotein, and COX5B, which encodes the Vb subunit of the mitochondrial complex cytochrome c oxidase. However, factors controlling IXR1 expression remained unexplored. In the present study we show that IXR1 mRNA levels are controlled by oxygen availability and increase during hypoxia. In aerobiosis, low levels of IXR1 expression are maintained by Rox1p repression through the general co-repressor complex Tup1–Ssn6. Ixr1p itself is necessary for full IXR1 expression under hypoxic conditions. Deletion analyses have identified the region in the IXR1 promoter responsible for this positive auto-control (nucleotides −557 to −376). EMSA (electrophoretic mobility-shift assay) and ChIP (chromatin immunoprecipitation) assays show that Ixr1p binds to the IXR1 promoter both in vitro and in vivo. Ixr1p is also required for hypoxic repression of ROX1 and binds to its promoter. UPC2 deletion has opposite effects on IXR1 and ROX1 transcription during hypoxia. Ixr1p is also necessary for resistance to oxidative stress generated by H2O2. IXR1 expression is moderately activated by H2O2 and this induction is Yap1p-dependent. A model of IXR1 regulation as a relay for sensing different signals related to change in oxygen availability is proposed. In this model, transcriptional adaptation from aerobiosis to hypoxia depends on ROX1 and IXR1 cross-regulation.

scholarly journals Endometritis and In Vitro PGE2 Challenge Modify Properties of Cattle Endometrial Mesenchymal Stem Cells and Their Transcriptomic Profile

2017 ◽  
Vol 2017 ◽  
pp. 1-16 ◽  
Author(s):  
Evelyn Lara ◽  
Alejandra Velásquez ◽  
Joel Cabezas ◽  
Nathaly Rivera ◽  
Paulina Pacha ◽  
...  
Keyword(s):  
Stem Cells ◽  
Immune Response ◽  
Cell Proliferation ◽  
Mesenchymal Stem Cells ◽  
Inflammatory Mediator ◽  
Adipogenic Differentiation ◽  
Morphological Features ◽  
Differentially Expressed ◽  
Transcriptomic Profile

Mesenchymal stem cells (MSCs) were isolated and characterized from postpartum bovine endometrium of animals with subclinical (n=5) and clinical endometritis (n=3) and healthy puerperal females (n=5). Cells isolated displayed mean morphological features of MSCs and underwent osteogenic, chondrogenic, and adipogenic differentiation after induction (healthy and subclinical). Cells from cows with clinical endometritis did not undergo adipogenic differentiation. All cells expressed mRNAs for selected MSC markers. Endometrial MSCs were challenged in vitro with PGE2 at concentrations of 0, 1, 3, and 10 μM, and their global transcriptomic profile was studied. Overall, 1127 genes were differentially expressed between unchallenged cells and cells treated with PGE2 at all concentrations (763 up- and 364 downregulated, fold change > 2, and P<0.05). The pathways affected the most by the PGE2 challenge were immune response, angiogenesis, and cell proliferation. In conclusion, we demonstrated that healthy puerperal bovine endometrium contains MSCs and that endometritis modifies and limits some functional characteristics of these cells, such as their ability to proceed to adipogenic differentiation. Also, PGE2, an inflammatory mediator of endometritis, modifies the transcriptomic profile of endometrial MSCs. A similar situation may occur during inflammation associated with endometritis, therefore affecting the main properties of endometrial MSCs.

scholarly journals Advanced Bio-Based Polymers for Astrocyte Cell Models

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3664
Author(s):  
Lidija Gradišnik ◽  
Roman Bošnjak ◽  
Tina Maver ◽  
Tomaž Velnar
Keyword(s):  
Brain Injuries ◽  
Neural Interfaces ◽  
Patterned Surfaces ◽  
Cell Models ◽  
Regenerative Processes ◽  
Human Astrocytes ◽  
New Findings ◽  
The Central Nervous System ◽  
Cell Material Interactions

The development of in vitro neural tissue analogs is of great interest for many biomedical engineering applications, including the tissue engineering of neural interfaces, treatment of neurodegenerative diseases, and in vitro evaluation of cell–material interactions. Since astrocytes play a crucial role in the regenerative processes of the central nervous system, the development of biomaterials that interact favorably with astrocytes is of great research interest. The sources of human astrocytes, suitable natural biomaterials, guidance scaffolds, and ligand patterned surfaces are discussed in the article. New findings in this field are essential for the future treatment of spinal cord and brain injuries.

scholarly journals A 2.5-Kilobase Deletion Containing a Cluster of Nine MicroRNAs in the Latency-Associated-Transcript Locus of the Pseudorabies Virus Affects the Host Response of Porcine Trigeminal Ganglia during Established Latency

2014 ◽  
Vol 89 (1) ◽  
pp. 428-442 ◽  
Author(s):  
Nada Mahjoub ◽  
Sophie Dhorne-Pollet ◽  
Walter Fuchs ◽  
Marie-Laure Endale Ahanda ◽  
Elke Lange ◽  
...  
Keyword(s):  
Immune Response ◽  
Host Response ◽  
Pseudorabies Virus ◽  
Differentially Expressed ◽  
Viral Reactivation ◽  
Trigeminal Ganglia ◽  
Mirna Genes ◽  
Pathway Analyses ◽  
Simplex Virus

ABSTRACTThe alphaherpesvirus pseudorabies virus (PrV) establishes latency primarily in neurons of trigeminal ganglia when only the transcription of the latency-associated transcript (LAT) locus is detected. Eleven microRNAs (miRNAs) cluster within the LAT, suggesting a role in establishment and/or maintenance of latency. We generated a mutant (M) PrV deleted of nine miRNA genes which displayed properties that were almost identical to those of the parental PrV wild type (WT) during propagationin vitro. Fifteen pigs were experimentally infected with either WT or M virus or were mock infected. Similar levels of virus excretion and host antibody response were observed in all infected animals. At 62 days postinfection, trigeminal ganglia were excised and profiled by deep sequencing and quantitative RT-PCR. Latency was established in all infected animals without evidence of viral reactivation, demonstrating that miRNAs are not essential for this process. Lower levels of the large latency transcript (LLT) were found in ganglia infected by M PrV than in those infected by WT PrV. All PrV miRNAs were expressed, with highest expression observed for prv-miR-LLT1, prv-miR-LLT2 (in WT ganglia), and prv-miR-LLT10 (in both WT and M ganglia). No evidence of differentially expressed porcine miRNAs was found. Fifty-four porcine genes were differentially expressed between WT, M, and control ganglia. Both viruses triggered a strong host immune response, but in M ganglia gene upregulation was prevalent. Pathway analyses indicated that several biofunctions, including those related to cell-mediated immune response and the migration of dendritic cells, were impaired in M ganglia. These findings are consistent with a function of the LAT locus in the modulation of host response for maintaining a latent state.IMPORTANCEThis study provides a thorough reference on the establishment of latency by PrV in its natural host, the pig. Our results corroborate the evidence obtained from the study of several LAT mutants of other alphaherpesviruses encoding miRNAs from their LAT regions. Neither PrV miRNA expression nor high LLT expression levels are essential to achieve latency in trigeminal ganglia. Once latency is established by PrV, the only remarkable differences are found in the pattern of host response. This indicates that, as in herpes simplex virus, LAT functions as an immune evasion locus.

scholarly journals Differential mRNA and miRNA Profiles Reveal the Potential Roles of Genes and miRNAs Involved in LPS Infection in Chicken Macrophages

Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 760
Author(s):  
Qi Zhang ◽  
Jie Wang ◽  
Jin Zhang ◽  
Jie Wen ◽  
Guiping Zhao ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Immune Response ◽  
Target Genes ◽  
Differentially Expressed ◽  
Gram Negative Bacteria ◽  
Potential Candidate ◽  
Gram Negative ◽  
Immune Related Genes

Lipopolysaccharide (LPS) is a component of the cell wall of Gram-negative bacteria, and triggers an inflammatory response both in vitro and in vivo. Here, we used LPS from Escherichia coli serotype enteritidis to stimulate chicken macrophages (HD11) and conducted the transcriptome analysis using a bioinformatics approach to explore the functions of immune-related genes and miRNAs. In total, 1759 differentially expressed genes (DEGs) and 18 differentially expressed (DE)-miRNAs were detected during LPS infection. At 6 h post infection, 1025 DEGs and 10 miRNAs were up-regulated, and 734 DEGs and 8 DE-miRNAs were down-regulated. Based on both RNA hybrid and miRanda systems, 55 DEGs could be targeted by 14 DE-miRNAs. The target genes were related to the immune response, such as IRF8, STAT3, TRAF7, and other potential candidate genes. The DE-miRNAs miR146a-3p, miR6583-5p, and miR30c-2-3p were investigated further. They were predicted to target 34 genes that may also be candidates for immune-related miRNAs and genes. Our results enhanced our understanding of the pathogenic mechanisms of Gram-negative bacteria in chickens.

Systemic Effects of ADP-induced Platelet Aggregation and Their Modification by Aspirin and by Pyridinolcarbamate

1973 ◽  
Vol 30 (01) ◽  
pp. 178-190 ◽  
Author(s):  
Itsuro Kobayashi ◽  
Paul Didisheim
Keyword(s):  
Platelet Aggregation ◽  
Venous Pressure ◽  
Systemic Effects ◽  
Central Venous ◽  
Platelet Aggregates ◽  
Induced Changes ◽  
Second Wave ◽  
Carotid Arterial ◽  
Arterial Po2

SummaryADP, AMP, or ATP was injected rapidly intravenously in rats. ADP injection resulted in the f olio wing transient changes: a drop in platelet count, a rise in central venous pressure, a fall in carotid arterial PO2, bradycardia, arrhythmia, flutter-fibrillation, and arterial hypotension. AMP and ATP produced some of these same effects; but except for hypotension, their frequency and severity Avere much less than those following ADP.Prior intravenous administration of acetylsalicylic acid or pyridinolcarbamate, two inhibitors of the second wave of ADP-induced platelet aggregation in vitro, significantly reduced the frequency and severity of all the above ADP-induced changes except hypotension. These observations suggest that many of the changes (except hypotension) observed to follow ADP injection are produced by platelet aggregates which lodge transiently in various microcirculatory beds then rapidly disaggregate and recirculate.

Sign in / Sign up

Export Citation Format

Share Document