Single-cell transcriptomic profile of satellite glial cells in trigeminal ganglion

Abstract

Satellite glial cells (SGCs) play an important role in regulating the function of trigeminal ganglion (TG) neurons. Multiple mediators are involved in the bidirectional communication between SGCs and neurons in different physiological and pathological states. However, molecular insights into the transcript characteristics of SGCs are limited. Moreover, little is known about the heterogeneity of SGCs in TG, and a more in-depth understanding of the interactions between SGCs and neuron subtypes is needed. Here we show the single-cell RNA sequencing (scRNA-seq) profile of SGCs in TG under physiological conditions. Our results demonstrate TG includes nine types of cell clusters, such as neurons, SGCs, myeloid Schwann cells (mSCs), non-myeloid Schwann cells (nmSCs), immune cells, etc., and the corresponding markers are also presented. We reveal the signature gene expression of SGCs, mSCs and nmSCs in the TG, and analyze the ligand-receptor pairs between neuron subtypes and SGCs in the TG. In the heterogeneity analysis of SGCs, four SGCs subtypes are identified, including subtypes enriched for genes associated with extracellular matrix organization, immediate early genes, interferon beta, and cell adhesion molecules, respectively. Our data suggest the molecular characteristics, heterogeneity of SGCs, and bidirectional interactions between SGCs and neurons, providing a valuable resource for studying SGCs in the TG.

Single-nucleus transcriptome analysis reveals transcriptional profiles of circadian clock and pain related genes in human and mouse trigeminal ganglion

“…Unlike scRNA-seq, snRNA-seq analyzes single nuclei instead of single cells, which solves the problem of isolating neural tissues and other tissues into single-cell suspensions and frozen samples for sequencing, facilitating human tissue sequencing, while minimizing cellular transcriptional changes caused by dissociation ( Lacar et al, 2016 ). In the snRNA-seq analysis of this study, we reveal that the human and mouse TG have the same cell types, including six major cell clusters, which are consistent with other published scRNA-seq studies on sensory ganglia ( Avraham et al, 2020 ; Mapps et al, 2022 ; Chu et al, 2023 ). Moreover, traditional approach neurons are classified according to anatomical, physiological, and biochemical characteristics, but the heterogeneity of neurons in sensory ganglia at the transcriptional level is not well understood.…”

“…The non-parametric Wilcoxon rank sum test was performed in the differential gene analysis, with the p -value set at <0.01. The calculated top marker genes of the cell clusters were compared with other published scRNA-seq studies of the nervous system ( Avraham et al, 2020 ; Yang et al, 2022 ; Chu et al, 2023 ) to determine the identity of the cell clusters including neurons, glial cells, and other non-neural cells in the TG. The annotations of the cell clusters in the TG were validated by automated cell annotation using the SingleR R package v1.4.1.…”

Expression of Cannabinoid Receptors in the Trigeminal Ganglion of the Horse

“…However, the headshaking in horses appear to d functional rather than structural abno control and headshaking horses ident nerve in affected horses was sensitise affected horses [3]. -IR in SGCs of the horse TG may play an important role in ganglion functional homeostasis, as also indicated in mice by Chu et al [62]. Also, the expression of PPAR…”

Regulation of headache response and transcriptomic network by the trigeminal ganglion clock

“…Located outside of the blood‐brain barrier, the TG is an immensely important structure as it is the putative target of dual migraine/CH medications that do not cross the blood‐brain barrier in significant amounts, 19,20 such as ergotamine 21 and monoclonal antibodies to calcitonin gene‐related peptide (CGRP) 22 . The TG transcriptome has been shown to be highly conserved between mice and humans, and single‐cell analysis at one time point has shown the presence of core clock gene expression in multiple cell types 23,24 . Moreover, preliminary evidence suggests that the TG can cause circadian patterns of pain in humans: trigeminal neuralgia, a facial pain disorder often resulting from vascular compression of the trigeminal nerve, 25 also displays a circadian periodicity of attacks 26 .…”

“…22 The TG transcriptome has been shown to be highly conserved between mice and humans, and single-cell analysis at one time point has shown the presence of core clock gene expression in multiple cell types. 23,24 Moreover, preliminary evidence suggests that the TG can cause circadian patterns of pain in humans: trigeminal neuralgia, a facial pain disorder often resulting from vascular compression of the trigeminal nerve, 25 also displays a circadian periodicity of attacks. 26 These observations suggest that the TG may play an important role in the circadian rhythmicity of headaches and facial pain; however, the clock network in the TG has not been characterized, and how it responds to pain remains unclear.…”