Project description:This study explores the circuit integration of human glioblastoma organoids (GBOs) in vivo in the adult mouse brain. We performed single cell RNA sequencing (scRNA-seq) to understand the cell state diversity of malignant tumor cells in GBOs at baseline and after stimulation by 1 mM acetylcholine (ACh) for 1 hour. Sliced neocortical organoids (SNOs) were also sequenced to study gene expression properties of neural stem cells (NSCs).
Project description:This study explores the circuit integration of human glioblastoma organoids (GBOs) in vivo in the adult mouse brain. Here, we performed RNA sequencing analysis of GBOs at baseline conditions and various treatment timepoints of 1 mM acetylcholine (ACh). RNA sequencing analysis was also performed on GBOs with CHRM3 knockdown.
Project description:Gene expression profiling of distinct members of a neuronal circuit has the potential to identify candidate molecules and mechanisms that underlie the formation, organization and function of the circuit. To this end, we report here the application of a novel method to characterize RNAs from small numbers of specific Drosophila brain neurons, which belong to the circadian circuit. We identified three different sets of mRNAs enriched in different subclasses of clock neurons: one is enriched in all clock neurons, a second is enriched in PDF-positive clock neurons and a third is enriched in PDF-negative clock neurons. Moreover, we characterized 2 novel genes, Fer2 and dnocturnin, one from each subgroup, which highlight subgroup-specific features and play important roles in circadian rhythms. The methodology is a powerful tool not only to dissect the cellular and molecular basis of circadian rhythms but also to molecularly characterize other Drosophila neuronal circuits. Experiment Overall Design: Circadican related neuronal celltypes (Tim, Pdf) or general neurons (Elav) were labeled by GFP or YFP using specific Gal4 drivers. Expression of those celltypes were profiled after manual sorting of those GFP or YFP positive cells. 3 biological replicates were collected (except adult small pdf cells).
Project description:Gene expression profiling of distinct members of a neuronal circuit has the potential to identify candidate molecules and mechanisms that underlie the formation, organization and function of the circuit. To this end, we report here the application of a novel method to characterize RNAs from small numbers of specific Drosophila brain neurons, which belong to the circadian circuit. We identified three different sets of mRNAs enriched in different subclasses of clock neurons: one is enriched in all clock neurons, a second is enriched in PDF-positive clock neurons and a third is enriched in PDF-negative clock neurons. Moreover, we characterized 2 novel genes, Fer2 and dnocturnin, one from each subgroup, which highlight subgroup-specific features and play important roles in circadian rhythms. The methodology is a powerful tool not only to dissect the cellular and molecular basis of circadian rhythms but also to molecularly characterize other Drosophila neuronal circuits.
Project description:We have developed a nonheuristic genome topography scan (GTS) algorithm to characterize the patterns of genomic alterations in human glioblastoma (GBM), identifying frequent p18INK4C and p16INK4A codeletion. Functional reconstitution of p18INK4C in GBM cells null for both p16INK4A and p18INK4C resulted in impaired cell-cycle progression and tumorigenic potential. Conversely, RNAi-mediated depletion of p18INK4C in p16INK4A-deficient primary astrocytes or established GBM cells enhanced tumorigenicity in vitro and in vivo. Furthermore, acute suppression of p16INK4A in primary astrocytes induced a concomitant increase in p18INK4C. Together, these findings uncover a feedback regulatory circuit in the astrocytic lineage and demonstrate a bona fide tumor suppressor role for p18INK4C in human GBM wherein it functions cooperatively with other INK4 family members to constrain inappropriate proliferation. Keywords: SuperSeries DNA copy number and mRNA transcriptome of human glioblastoma tumors were profiled using Agilent and Affymetrix microarrays. This SuperSeries is composed of the following subset Series: GSE7602: Human GBM tumor vs Normal Human DNA GSE9171: Expression data from human GBM tumors and cell lines GSE9177: Human GBM tumor vs Normal Human DNA
Project description:Gliomas synaptically integrate into neural circuits. Prior work has demonstrated bidirectional interactions between neurons and glioma cells, with neuronal activity driving glioma growth and gliomas increasing neuronal excitability. In this study we sought to determine how glioma-induced neuronal changes influence neural circuits underlying cognition and whether these interactions influence patient survival. Using intracranial brain recordings during lexical retrieval language tasks in awake humans together with site-specific tumor tissue biopsies and cell biology experiments, we found that gliomas remodel functional neural circuitry such that task-relevant neural responses activate tumor-infiltrated cortex well beyond the cortical regions normally recruited in the healthy brain. Site-directed biopsies from regions within the tumor that exhibit high functional connectivity between the tumor and the rest of the brain are enriched for a glioblastoma subpopulation that exhibits a distinct synaptogenic and neuronotrophic phenotype. Tumor cells from functionally connected regions secrete the synaptogenic factor thrombospondin-1, which contributes to the differential neuron-glioma interactions observed in functionally connected tumor regions compared to tumor regions with less functional connectivity. Pharmacological inhibition of thrombospondin-1 through the FDA-approved drug, gabapentin decreases glioblastoma proliferation. The degree of functional connectivity between glioblastoma and the normal brain negatively impacts both patient survival and language task performance. These data demonstrate that high-grade gliomas functionally remodel neural circuits in the human brain, which both promotes tumor progression and impairs cognition.
Project description:The body-brain axis is emerging as a principal conductor of organismal physiology. It senses and controls organ function, metabolism and nutritional state. Here, we show that a peripheral immune insult powerfully activates the body-brain axis to regulate immune responses. We demonstrate that pro- and anti-inflammatory cytokines communicate with distinct populations of vagal neurons to inform the brain of an emerging inflammatory response. In turn, the brain tightly modulates the course of the peripheral immune response. Genetic silencing of this body-to-brain circuit produced unregulated and out-of-control inflammatory responses. By contrast, activating, rather than silencing, this circuit affords exceptional neural control of immune responses. We used single-cell RNA sequencing, combined with functional imaging, to identify the circuit components of this neuro-immune axis, and showed that its selective manipulation can effectively suppress the pro-inflammatory response while enhancing an anti-inflammatory state. The brain-evoked transformation of the course of an immune response offers new possibilities in the modulation of a wide range of immune disorders, from autoimmune diseases to cytokine storm and shock.
Project description:Gut-brain connections monitor the intestinal tissue and its microbial and dietary content1, regulating both intestinal physiological functions such as nutrient absorption and motility2,3, and brain–wired feeding behaviour2. It is therefore plausible that circuits exist to detect gut microbes and relay this information to central nervous system (CNS) areas that, in turn, regulate gut physiology4. We characterized the influence of the microbiota on enteric–associated neurons (EAN) by combining gnotobiotic mouse models with transcriptomics, circuit–tracing methods, and functional manipulation. We found that the gut microbiome modulates gut–extrinsic sympathetic neurons; while microbiota depletion led to increased cFos expression, colonization of germ-free mice with short-chain fatty acid–producing bacteria suppressed cFos expression in the gut sympathetic ganglia. Chemogenetic manipulations, translational profiling, and anterograde tracing identified a subset of distal intestine-projecting vagal neurons positioned to play an afferent role in microbiota–mediated modulation of gut sympathetic neurons. Retrograde polysynaptic neuronal tracing from the intestinal wall identified brainstem sensory nuclei activated during microbial depletion, as well as efferent sympathetic premotor glutamatergic neurons that regulate gastrointestinal transit. These results reveal microbiota–dependent control of gut extrinsic sympathetic activation through a gut-brain circuit.
Project description:Signals from sympathetic neurons and immune cells regulate adipocytes contributing to fat tissue biology. Interactions between the nervous and immune systems have recently emerged as major regulators of host defence and inflammation1-4. Nevertheless, whether neuronal and immune cells cooperate in brain-body axes to orchestrate metabolism and obesity remains elusive. Here we report a novel neuro-mesenchyme unit that controls group 2 innate lymphoid cells (ILC2), adipose tissue physiology, metabolism and obesity via a brain-adipose circuit. We found that sympathetic nerve terminals act on neighbouring adipose mesenchymal cells via the beta-2 adrenergic receptor to control the expression of the glial-derived neurotrophic factor (GDNF) and the activity of ILC2 in gonadal fat. Accordingly, ILC2-autonomous manipulation of the GDNF receptor machinery led to altered ILC2 function, energy expenditure, insulin resistance and propensity to obesity. Retrograde tracing, chemical, surgical and chemogenetic manipulations identified a sympathetic aorticorenal circuit that modulates gonadal fat ILC2 and connects to high-order brain areas, including the paraventricular nucleus of the hypothalamus (PVH). Our work decodes a neuro-mesenchymal unit that translates long-range neuronal circuitry cues into adipose-resident ILC2 function, shaping the host metabolism and obesity.