Dataset Information

Traumatic Brain Injury Stimulates Sympathetic Tone-mediated Bone Marrow Myelopoiesis to Favor Fracture Healing

ABSTRACT: Traumatic brain injury (TBI) accelerates fracture healing, but the underlying mechanism remains largely unknown. Accumulating evidence indicates that the central nervous system plays a pivotal role in regulating immune system and skeleton, however, the impact of TBI on hematopoiesis commitment was overlooked. Here, we found that the dramatically elevated sympathetic tone accompanied with TBI-accelerated fracture healing; chemical sympathectomy blocks TBI-induced fracture healing. Importantly, the adrenergic hypersensitivity swiftly skews bone marrow hematopoietic lineage cells toward anti-inflammation myeloid cells within 14 days, which favor fracture healing. Knockout of β3- or β2-adrenergic receptors (ARs) eliminate TBI mediated anti-inflammation macrophage expansion and TBI-accelerated fracture healing. Moreover, β3- and β2-ARs agonists synergistically promote M2 macrophages infiltration in callus and accelerate bone healing process. Our results suggest that TBI shapes the anti-inflammation environment during early stage of fracture healing, implicating the sympathetic nerve system as a potential target that can be exploited to treat fracture.

ORGANISM(S): Mus musculus

PROVIDER: GSE229258 | GEO | 2023/04/12

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:It is commonly observed that patients with bone fracture concomitated with traumatic brain injury (TBI) had significantly increased fracture healing while the underlying mechanisms were not fully revealed. Long non-coding RNAs (lncRNAs) were known for paly complicated roles in bone homeostasis while its role in TBI accelerated fracture were rarely reported. The present study was designed to determine the role of lncRNAs in TBI accelerated fracture via transcriptome sequencing and further bioinformatical analysis. Blood samples from 3 fracture only patients, 3 fracture concomitated with TIB patients and 3 healthy controls were harvested and were subsequently subjected to transcriptome lncRNAs sequencing. Differentially expression genes were identified, and pathway enrichment were performed by Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyze. High high-dimensional data portraying by self-organizing map (SOM) machine learning was applied to further interpret the data. A xCell method were then used to predict cellular behavior in all samples based on gene expression profiles and a lncRNA-cell interaction network were generated. A total of 874 differentially expressed genes were identified, of which about 26% were lncRNAs. Those identified lncRNAs were mainly enriched on traumatic brain injury related- and damage repair related-pathways. SOM analyzes revealed that those differentially expressed lncRNAs could be divided into three major module implications and were mainly enriched on transcriptional regulation and immune related signal pathways, which promote us to further explore cellular behaviors based on differentially expressed lncRNAs. We have predicted that basophils, CD8+ T effector memory cells, B cells, and naïve B cells were significantly down-regulated while microvascular endothelia cells were predicated significantly up-regulated with TBI/Fr group was the lowest or highest, respectively. ENSG00000278905, ENSG00000240980, ENSG00000255670, and ENSG00000196634 were the most differentially expression lcnRNA that related to all changes of cellular behavior. The present study has revealed for the first time that several critical lncRNAs may participate in TBI accelerated fracture potentially via regulating cellular behaviors of basophils, cytotoxic T cells, B cells and endothelia cells.

Project description:BACKGROUND Enteric glia contribute to the pathophysiology of various intestinal immune-driven diseases, such as postoperative ileus (POI), a motility disorder and common complication after abdominal surgery. Enteric gliosis of the intestinal muscularis externa (ME) has been identified as part of POI development. However, the glia-restricted responses and activation mechanisms are poorly understood. The sympathetic nervous system becomes rapidly activated by abdominal surgery. It modulates intestinal immunity, innervates all intestinal layers, and directly interfaces with enteric glia. We hypothesized that sympathetic innervation controls enteric glia reactivity in response to surgical trauma. METHODS Sox10iCreERT2/Rpl22HA/+ mice were subjected to a mouse model of laparotomy or intestinal manipulation to induce POI. Histological, protein, and transcriptomic analyses were performed to analyze glia-specific responses. Interactions between the sympathetic nervous system and enteric glia were studied in mice chemically depleted of TH+ sympathetic neurons and glial-restricted Sox10iCreERT2/JellyOPfl/+/Rpl22HA/+ mice, allowing optogenetic stimulation of β-adrenergic downstream signaling and glial-specific transcriptome analyses. A laparotomy model was used to study the effect of sympathetic signaling on enteric glia in the absence of intestinal manipulation. Mechanistic studies included adrenergic receptor expression profiling in vivo and in vitro and adrenergic agonism treatments of primary enteric glial cell cultures to elucidate the role of sympathetic signaling in acute enteric gliosis and POI. RESULTS With ~4000 differentially expressed genes, the most substantial enteric glia response occurs early after intestinal manipulation. During POI, enteric glia switch into a reactive state and continuously shape their microenvironment by releasing inflammatory and migratory factors. Sympathetic denervation reduced the inflammatory response of enteric glia in the early postoperative phase. Optogenetic and pharmacological stimulation of β-adrenergic downstream signaling triggered enteric glia reactivity. Finally, distinct adrenergic agonists revealed β-1/2 adrenoceptors as the molecular targets of sympathetic–driven enteric glial reactivity. CONCLUSIONS Enteric glia act as early responders during post-traumatic intestinal injury and inflammation. Intact sympathetic innervation and active β-adrenergic receptor signaling in enteric glia is a trigger of the immediate glial postoperative inflammatory response. With immune-activating cues originating from the sympathetic nervous system as early as the initial surgical incision, adrenergic signaling in enteric glia presents a promising target for preventing POI development.

Dataset Information

Traumatic Brain Injury Stimulates Sympathetic Tone-mediated Bone Marrow Myelopoiesis to Favor Fracture Healing

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure