Transciption profiling of leptin receptor-expressing neurons in the Nucleus of the Solitary Tract
Ontology highlight
ABSTRACT: This study aims to identify and compare unique transcription profiles of neurons in the NTS that express the leptin receptor. We conducted single-cell patch RNA-sequencing experiments to classify neurons first by their unique firing properties and, second, transciptional profiles. We found two unique cellular populations: type1 and type2 distinguishable by firing patterns and transciption profile.
Project description:While the response to G-CSF is a significant predictor of AML outcome, the nature of cells responding differentially to this and other cytokines remains unclear. Based on gene expression signatures observed in G-CSF Responsive Cells (RC) and non-G-CSF Responsive Cells (NRC) a cohort of AML samples were segregated into two types. In Type1 both cell subsets displayed an undifferentiated phenotype. In the Type2 AML the RC showed a very similar undifferentiated progenitor-like phenotype as in Type1 RC, whereas the NRC exhibited a more differentiated hematopoietic phenotype. The frequency of RC per sample was a determinant of whether a patient belonged to Type1 or Type2. Type2 RC had higher expression of CD321, higher colony formation capacity and greater responsiveness to cytokines secreted by NRC. Further analysis of clinical mRNA databases revealed that CD321 was a prognostic indicator for AML and a potential marker of clonogenic activity associated with this AML cancer lineage. Cryopreserved PBMC from 11 AML patinets were stimulated with G-CSF. Following stimulation cells were fixed, permeabilized and stained for selected surface markers (CD3, CD33, CD45) and and phospho-Stat3/5. After staining subsets positive and negative for phospo-Stat3/5 were sorted out for further microarray analysis. T-cells were sorted from each sample to control for the RNA quality by comparisons to RNA prepared from live T-cells sorted form healthy donors.
Project description:Sex Specific Transciption in Human Hypothalamus between 7 male biological samples (2 technical replicates of each) and 5 female biological samples (2 technical replicates of 4 of these). Keywords = human hypothalamus, sex-specific transcription Keywords: other
Project description:Sex Specific Transciption in Mouse Hypothalamus, Liver, Kidney, Ovary and Testis. For each somatic tissue there are 3 biological samples from different pools comprised of 10 animals for each sex each with a technical replicate. For each of the reproductive tissues there are 3 biological samples from different pools comprised of 10 animals with a technical replicate for each. Keywords = Mouse sex-specific transcription, gonad specific gene expression Keywords: other
Project description:Our previous findings suggest that the nucleus of the solitary tract (NTS), a pivotal region for regulating the set-point of arterial pressure, exhibits abnormal inflammation in pre-hypertensive and spontaneously hypertensive rats (SHRs) together with elevated anti-apoptotic and low apoptotic factor levels compared with that of normotensive Wistar–Kyoto (WKY) rats. Whether this chronic condition affects neuronal growth and plasticity in the NTS remains unknown. To unveil the characteristics of the neurodevelopmental environment in the NTS of hypertensive rats, we investigated the gene expression profile of neurotrophins and their receptors in SHRs compared to that of normotensive rat WKY.
Project description:Our previous findings suggest that the nucleus of the solitary tract (NTS), a pivotal region for regulating the set-point of arterial pressure, exhibits abnormal inflammation in pre-hypertensive and spontaneously hypertensive rats (SHRs) together with elevated anti-apoptotic and low apoptotic factor levels compared with that of normotensive Wistar–Kyoto (WKY) rats. Whether this chronic condition affects neuronal growth and plasticity in the NTS remains unknown. To unveil the characteristics of the neurodevelopmental environment in the NTS of hypertensive rats, we investigated the gene expression profile of neurotrophins and their receptors in SHRs compared to that of normotensive rat WKY. The NTS was dissected from the brain of 6 SHRs and 6 WKY rats and the total RNA was extracted. In both groups of rats (SHRs & WKY rats, n = 6 each), a total of 2 ug mRNA extracts from each NTS were pooled together, treated with RNase-free DNAse I (Invitrogen Life technologies) to remove any genomic contamination, and further purified using the RNeasy mini kit (Qiagen) according to the manufacturer’s instructions. Reverse transcription was subsequently performed on 1 ug total RNA using SuperArray’s RT2 First Strand Kit (SABiosciences); the resulting cDNA was submitted for real-time quantitative PCR reactions on RT2 ProfilerTM PCR array plates using Superarray RT2 SYBR Green qPCR Master Mix (SAbiosciences) and iCycler iQ thermal cycler (Bio-rad), following the manufacturer’s instructions. The experiment was performed in duplicate in each group.
Project description:Exaggerated airway constriction triggered by exposure to irritants such as allergen, also called hyperreactivity, is a hallmark of asthma and can be life-threatening. Aside from immune cells, vagal sensory neurons are important for airway hyperreactivity 1-4. However, the identity and signature of the downstream nodes of this adaptive circuit remains poorly understood. Here we show that Dbh+ neurons in the nucleus of the solitary tract (nTS) of the brainstem, and downstream neurons in the nucleus ambiguus (NA), are both necessary and sufficient for chronic allergen-induced airway hyperreactivity. We found that repeated exposures of mice to inhaled allergen activates nTS neurons in a mast cell-, interleukin 4 (IL-4)- and vagal nerve-dependent manner. Single-nucleus RNA-seq followed by RNAscope quantification of the nTS at baseline and following allergen challenges reveals that a Dbh+ population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted, while chemogenetic activation promoted hyperreactivity. Viral tracing indicates that Dbh+ nTS neurons, capable of producing norepinephrine, project to the NA, and NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that then directly drive airway constriction. Focusing on transmitters, delivery of norepinephrine antagonists to the NA blunted allergen-induced hyperreactivity. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. The knowledge opens the possibility of targeting neural modulation as an approach to control allergen-induced airway constriction.
Project description:Exaggerated airway constriction triggered by exposure to irritants such as allergen, also called hyperreactivity, is a hallmark of asthma and can be life-threatening. Aside from immune cells, vagal sensory neurons are important for airway hyperreactivity 1-4. However, the identity and signature of the downstream nodes of this adaptive circuit remains poorly understood. Here we show that Dbh+ neurons in the nucleus of the solitary tract (nTS) of the brainstem, and downstream neurons in the nucleus ambiguus (NA), are both necessary and sufficient for chronic allergen-induced airway hyperreactivity. We found that repeated exposures of mice to inhaled allergen activates nTS neurons in a mast cell-, interleukin 4 (IL-4)- and vagal nerve-dependent manner. Single-nucleus RNA-seq followed by RNAscope quantification of the nTS at baseline and following allergen challenges reveals that a Dbh+ population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted, while chemogenetic activation promoted hyperreactivity. Viral tracing indicates that Dbh+ nTS neurons, capable of producing norepinephrine, project to the NA, and NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that then directly drive airway constriction. Focusing on transmitters, delivery of norepinephrine antagonists to the NA blunted allergen-induced hyperreactivity. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. The knowledge opens the possibility of targeting neural modulation as an approach to control refractory allergen-induced airway constriction.