Aging is a major risk factor for many neurological pathologies, including Alzheimer's disease (AD). However, the mechanisms underlying brain aging and cognitive decline remain elusive. Body tissues are perfused by interstitial fluid (ISF), which is locally reabsorbed via the lymphatic vascular network. In contrast, the parenchyma of the central nervous system (CNS) is devoid of lymphatic vasculature; in the brain, removal of cellular debris and toxic molecules, such as amyloid beta (A?) peptides, is mediated by a combination of transcellular mechanisms of transport across the blood-brain and blood-cerebrospinal fluid (CSF) barriers, phagocytosis and digestion by resident microglia and recruited monocytes/macrophages, and CSF influx and ISF efflux through a paravascular route. The recent characterization of meningeal lymphatic vessels prompted a reassessment of the conventional pathways of CNS waste clearance. The role of this vasculature in brain function, specifically in the context of aging and AD, is still poorly understood. Here we show that meningeal lymphatic vessels play an essential role in maintaining brain homeostasis by draining macromolecules from the CNS (CSF and ISF) into the cervical lymph nodes. Using pharmacological, surgical, and genetic models we show that impairment of meningeal lymphatic function in adult mice slows paravascular influx of CSF macromolecules and efflux of ISF macromolecules, and induces cognitive impairment. Treatment with a lymphangiogenic factor, vascular endothelial growth factor C (VEGF-C), enhances meningeal lymphatic drainage of CSF macromolecules, improving brain perfusion and learning and memory performance in aged mice. Disruption of meningeal lymphatic vessels in transgenic mouse models of AD promotes amyloid deposition in the meninges, which closely correlates with human meningeal pathology, and aggravates overall disease severity. Our findings suggest that meningeal lymphatic dysfunction may be an aggravating factor in AD pathology and in age-associated cognitive decline. Thus, augmentation of meningeal lymphatic function might be a promising therapeutic target for preventing or delaying age-associated neurological diseases. Overall design: Male C57BL/6J mice (2 months-old) were injected (intra-cisterna magna) with Visudyne (verteporfin for injection), or vehicle as control, and submitted to a step of photoconversion, to induce meningeal lymphatic vessel ablation. This procedure was repeated 2 weeks later to ensure prolonged meningeal lymphatic dysfunction. 2 weeks after the last surgical procedure, mice were subjected to the MWM test. 3 days after, whole hippocampus was macrodissected and total RNA was extracted for sequencing.
Functional aspects of meningeal lymphatics in ageing and Alzheimer's disease.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesAging is a major risk factor for many neurological pathologies, including Alzheimer's disease (AD). However, the mechanisms underlying brain aging and cognitive decline remain elusive. Body tissues are perfused by interstitial fluid (ISF), which is locally reabsorbed via the lymphatic vascular network. In contrast, the parenchyma of the central nervous system (CNS) is devoid of lymphatic vasculature; in the brain, removal of cellular debris and toxic molecules, such as amyloid beta (A?) peptides, is mediated by a combination of transcellular mechanisms of transport across the blood-brain and blood-cerebrospinal fluid (CSF) barriers, phagocytosis and digestion by resident microglia and recruited monocytes/macrophages, and CSF influx and ISF efflux through a paravascular route. The recent characterization of meningeal lymphatic vessels prompted a reassessment of the conventional pathways of CNS waste clearance. The role of this vasculature in brain function, specifically in the context of aging and AD, is still poorly understood. Here we show that meningeal lymphatic vessels play an essential role in maintaining brain homeostasis by draining macromolecules from the CNS (CSF and ISF) into the cervical lymph nodes. Using pharmacological, surgical, and genetic models we show that impairment of meningeal lymphatic function in adult mice slows paravascular influx of CSF macromolecules and efflux of ISF macromolecules, and induces cognitive impairment. Treatment with a lymphangiogenic factor, vascular endothelial growth factor C (VEGF-C), enhances meningeal lymphatic drainage of CSF macromolecules, improving brain perfusion and learning and memory performance in aged mice. Disruption of meningeal lymphatic vessels in transgenic mouse models of AD promotes amyloid deposition in the meninges, which closely correlates with human meningeal pathology, and aggravates overall disease severity. Our findings suggest that meningeal lymphatic dysfunction may be an aggravating factor in AD pathology and in age-associated cognitive decline. Thus, augmentation of meningeal lymphatic function might be a promising therapeutic target for preventing or delaying age-associated neurological diseases. Overall design: Male C57BL/6J mice (2 months-old) were injected (intra-cisterna magna) with Visudyne (verteporfin for injection), or vehicle as control, and submitted to a step of photoconversion, to induce meningeal lymphatic vessel ablation. This procedure was repeated 2 weeks later to ensure prolonged meningeal lymphatic dysfunction. 2 weeks after the last surgical procedure, whole hippocampus was macrodissected and total RNA was extracted for sequencing.
Functional aspects of meningeal lymphatics in ageing and Alzheimer's disease.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesAging is a major risk factor for many neurological pathologies, including Alzheimer's disease (AD). However, the mechanisms underlying brain aging and cognitive decline remain elusive. Body tissues are perfused by interstitial fluid (ISF), which is locally reabsorbed via the lymphatic vascular network. In contrast, the parenchyma of the central nervous system (CNS) is devoid of lymphatic vasculature; in the brain, removal of cellular debris and toxic molecules, such as amyloid beta (A?) peptides, is mediated by a combination of transcellular mechanisms of transport across the blood-brain and blood-cerebrospinal fluid (CSF) barriers, phagocytosis and digestion by resident microglia and recruited monocytes/macrophages, and CSF influx and ISF efflux through a paravascular route. The recent characterization of meningeal lymphatic vessels prompted a reassessment of the conventional pathways of CNS waste clearance. The role of this vasculature in brain function, specifically in the context of aging and AD, is still poorly understood. Here we show that meningeal lymphatic vessels play an essential role in maintaining brain homeostasis by draining macromolecules from the CNS (CSF and ISF) into the cervical lymph nodes. Using pharmacological, surgical, and genetic models we show that impairment of meningeal lymphatic function in adult mice slows paravascular influx of CSF macromolecules and efflux of ISF macromolecules, and induces cognitive impairment. Treatment with a lymphangiogenic factor, vascular endothelial growth factor C (VEGF-C), enhances meningeal lymphatic drainage of CSF macromolecules, improving brain perfusion and learning and memory performance in aged mice. Disruption of meningeal lymphatic vessels in transgenic mouse models of AD promotes amyloid deposition in the meninges, which closely correlates with human meningeal pathology, and aggravates overall disease severity. Our findings suggest that meningeal lymphatic dysfunction may be an aggravating factor in AD pathology and in age-associated cognitive decline. Thus, augmentation of meningeal lymphatic function might be a promising therapeutic target for preventing or delaying age-associated neurological diseases. Overall design: Lymphatic endothelial cells (LECs) were isolated from meninges of adult (2-3 months-old) or old (20-24 months-old) male C57BL/6 mice. Cells were sorted by FACS according to the following phenotype: CD45-CD31+PDPN+.
Functional aspects of meningeal lymphatics in ageing and Alzheimer's disease.
Specimen part, Cell line, Subject
View SamplesThe high mutation rate of HIV is linked to the generation of viruses expressing proteins with altered function whose impact on disease progression is unknown. We investigated the effects of HIV-1 viruses lacking Env, Vpr and Nef on CD4+ T cell gene expression using high-density DNA microarray analysis and functional assays.
Tat-induced FOXO3a is a key mediator of apoptosis in HIV-1-infected human CD4+ T lymphocytes.
No sample metadata fields
View SamplesHere we tested a hypothesis that epileptogenesis influences expression pattern of genes in the basolateral amygdala that are critical for fear conditioning. Whole genome molecular profiling of basolateral rat amygdala was performed to compare the transcriptome changes underlying fear learning in epileptogenic and control animals. Our analysis revealed that after acquisition of fear conditioning 26 genes were regulated differently in the basolateral amygdala of both groups. Thus, our study provides the first evidence that not only the damage to the neuronal pathways but also altered composition or activity level of molecular machinery responsible for formation of emotional memories within surviving pathways can contribute to impairment in emotional learning in epileptogenic animals. Understanding the function of those genes in emotional learning provides an attractive avenue for identification of novel drug targets for treatment of emotional disorders after epileptogenesis-inducing insult.
Epileptogenesis alters gene expression pattern in rats subjected to amygdala-dependent emotional learning.
No sample metadata fields
View SamplesSurvival of insects on a substrate containing toxic substances such as plant secondary metabolites or insecticides is dependent on the metabolism or excretion of those xenobiotics. The primary sites of xenobiotic metabolism are the midgut, Malpighian tubules and fat body. In general, these organs are treated as single tissues by online databases, but several studies have shown that gene expression within subsections of the midgut is compartmentalized. In this article, RNA sequencing analysis was used to investigate whole-genome expression in subsections of the third-instar larval midgut. The results support functional diversification in subsections of the midgut. Analysis of the expression of gene families that are implicated in the metabolism of xenobiotics suggests that metabolism may not be uniform along the midgut. These data provide a starting point for investigating gene expression and xenobiotic metabolism in the larval midgut. Overall design: Examination of expression in eight samples corresponding to compartments of gene expression in the midgut
Whole-genome expression analysis in the third instar larval midgut of Drosophila melanogaster.
Specimen part, Cell line, Subject
View SamplesProtein inhibitor of activated STAT3 (PIAS3) is an endogenous inhibitor of STAT3 that negatively regulates STAT3 transcriptional activity and cell growth and demonstrates limited expression in the majority of human squamous cell carcinomas of the lung. In the present study we sought to determine if PIAS3 inhibits cell growth in non-small cell lung cancer (NSCLC) cell lines by induction of apoptosis and further determine the dependence of PIAS3 activity on p53 status by using both wild-type and p53-null cells. Our results demonstrate that over-expression of PIAS3 promotes caspase 3 activation and PARP cleavage. Furthermore, the expression of pro-survival family members Bcl-xL and Bcl-2 is decreased. These effects were observed after both transient and regulated expression of exogenous PIAS3 and were independent of p53 status. Furthermore, while p53 can promote apoptosis by inhibition of STAT3 activity, PIAS3 inhibition of STAT3 activity was also p53 independent. Microarray experiments were performed to further investigate the STAT3-dependence of PIAS3-induced apoptosis by comparing the apoptotic gene expression signature induced by PIAS3 over-expression with that induced by STAT3 siRNA. The results showed that a subset of apoptotic genes, including CIDEC and DAPK2, were uniquely expressed only after PIAS3 expression. Thus, PIAS3 may represent a promising lung cancer therapeutic target because of its p53-independent efficacy as well as its potential to synergize with direct STAT3 inhibitors.
PIAS3 activates the intrinsic apoptotic pathway in non-small cell lung cancer cells independent of p53 status.
Specimen part, Cell line
View SamplesRNA sequencing technology has been carried out in order to evaluate mRNA expression changes after manipulation of miR-26a in both MCF-7 and MDA-MB-231 breast cancer cell lines. Overall design: To evaluate the entire set of genes modulated by miR-26a in breast cancer, we performed RNA-seq after ectopic manipulation of this miRNA. We over-expressed miR-26a in MCF-7 epithelial cancer cell lines and also reduced its activity by stably transfecting MDA-MB-231 mesenchymal-like cancer cell lines with a specific sponge vector. GO terms and pathway enriched analysis of the transcripts that significantly change upon miR-26 ectopic manipulation implicates miR-26ab in cell cycle, apoptosis, cell spreading and cell adhesion in breast cancer
Sustained expression of miR-26a promotes chromosomal instability and tumorigenesis through regulation of CHFR.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
DNA methylation status is more reliable than gene expression at detecting cancer in prostate biopsy.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Invasive lobular carcinoma cell lines are characterized by unique estrogen-mediated gene expression patterns and altered tamoxifen response.
Specimen part, Cell line, Treatment, Time
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