1
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Guo G, Chen J, Shen Q, Chen Z. Single-cell transcriptome analysis reveals distinct cell populations in dorsal root ganglia and their potential roles in diabetic peripheral neuropathy. PLoS One 2024; 19:e0306424. [PMID: 39083491 PMCID: PMC11290642 DOI: 10.1371/journal.pone.0306424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 06/17/2024] [Indexed: 08/02/2024] Open
Abstract
Diabetic peripheral neuropathy (DPN) is a common complication associated with diabetes, and can affect quality of life considerably. Dorsal root ganglion (DRG) plays an important role in the development of DPN. However, the relationship between DRG and the pathogenesis of DPN still lacks a thorough exploration. Besides, a more in-depth understanding of the cell type composition of DRG, and the roles of different cell types in mediating DPN are needed. Here we conducted single-cell RNA-seq (scRNA-seq) for DRG tissues isolated from healthy control and DPN rats. Our results demonstrated DRG includes eight cell-type populations (e.g., neurons, satellite glial cells (SGCs), Schwann cells (SCs), endothelial cells, fibroblasts). In the heterogeneity analyses of cells, six neuron sub-types, three SGC sub-types and three SC sub-types were identified, additionally, biological functions related to cell sub-types were further revealed. Cell communication analysis showed dynamic interactions between neurons, SGCs and SCs. We also found that the aberrantly expressed transcripts in sub-types of neurons, SGCs and SCs with DPN were associated with diabetic neuropathic pain, cell apoptosis, oxidative stress, etc. In conclusion, this study provides a systematic perspective of the cellular composition and interactions of DRG tissues, and suggests that neurons, SGCs and SCs play vital roles in the progression of DPN. Our data may provide a valuable resource for future studies regarding the pathophysiological effect of particular cell type in DPN.
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Affiliation(s)
- Guojun Guo
- Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jing Chen
- Department of Dermatology, Traditional Chinese and Western Medicine Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qixiao Shen
- Department of Orthopedics, Yangxin People’s Hospital, Huangshi, Hubei, China
| | - Zhenbing Chen
- Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
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2
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Jager SE, Goodwin G, Chisholm KI, Denk F. In vivo calcium imaging shows that satellite glial cells have increased activity in painful states. Brain Commun 2024; 6:fcae013. [PMID: 38638153 PMCID: PMC11024818 DOI: 10.1093/braincomms/fcae013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 11/22/2023] [Accepted: 01/17/2024] [Indexed: 04/20/2024] Open
Abstract
Satellite glial cells are important for proper neuronal function of primary sensory neurons for which they provide homeostatic support. Most research on satellite glial cell function has been performed with in vitro studies, but recent advances in calcium imaging and transgenic mouse models have enabled this first in vivo study of single-cell satellite glial cell function in mouse models of inflammation and neuropathic pain. We found that in naïve conditions, satellite glial cells do not respond in a time-locked fashion to neuronal firing. In painful inflammatory and neuropathic states, we detected time-locked signals in a subset of satellite glial cells, but only with suprathreshold stimulation of the sciatic nerve. Surprisingly, therefore, we conclude that most calcium signals in satellite glial cells seem to develop at arbitrary intervals not directly linked to neuronal activity patterns. More in line with expectations, our experiments also revealed that the number of active satellite glial cells was increased under conditions of inflammation or nerve injury. This could reflect the increased requirement for homeostatic support across dorsal root ganglion neuron populations, which are more active during such painful states.
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Affiliation(s)
- Sara E Jager
- Wolfson Centre for Age-related Diseases, King’s College London, Guy’s Campus, London SE1 1UL, UK
- Molecular Neuropharmacology and Genetics Laboratory, Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - George Goodwin
- Wolfson Centre for Age-related Diseases, King’s College London, Guy’s Campus, London SE1 1UL, UK
| | - Kim I Chisholm
- Pain Centre Versus Arthritis, School of Life Sciences, University of Nottingham, Nottingham NG5 1PB, UK
| | - Franziska Denk
- Wolfson Centre for Age-related Diseases, King’s College London, Guy’s Campus, London SE1 1UL, UK
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3
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Andersen OE, Poulsen JV, Farup J, de Morree A. Regulation of adult stem cell function by ketone bodies. Front Cell Dev Biol 2023; 11:1246998. [PMID: 37745291 PMCID: PMC10513036 DOI: 10.3389/fcell.2023.1246998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 08/14/2023] [Indexed: 09/26/2023] Open
Abstract
Adult stem cells play key roles in tissue homeostasis and regeneration. Recent evidence suggests that dietary interventions can significantly impact adult stem cell function. Some of these effects depend on ketone bodies. Adult stem cells could therefore potentially be manipulated through dietary regimens or exogenous ketone body supplementation, a possibility with significant implications for regenerative medicine. In this review we discuss recent findings of the mechanisms by which ketone bodies could influence adult stem cells, including ketogenesis in adult stem cells, uptake and transport of circulating ketone bodies, receptor-mediated signaling, and changes to cellular metabolism. We also discuss the potential effects of ketone bodies on intracellular processes such as protein acetylation and post-transcriptional control of gene expression. The exploration of mechanisms underlying the effects of ketone bodies on stem cell function reveals potential therapeutic targets for tissue regeneration and age-related diseases and suggests future research directions in the field of ketone bodies and stem cells.
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Affiliation(s)
- Ole Emil Andersen
- Department of Public Health, Aarhus University, Aarhus, Denmark
- Steno Diabetes Center Aarhus, Aarhus University, Aarhus, Denmark
| | | | - Jean Farup
- Steno Diabetes Center Aarhus, Aarhus University, Aarhus, Denmark
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
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4
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McGinnis A, Ji RR. The Similar and Distinct Roles of Satellite Glial Cells and Spinal Astrocytes in Neuropathic Pain. Cells 2023; 12:965. [PMID: 36980304 PMCID: PMC10047571 DOI: 10.3390/cells12060965] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 03/19/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Preclinical studies have identified glial cells as pivotal players in the genesis and maintenance of neuropathic pain after nerve injury associated with diabetes, chemotherapy, major surgeries, and virus infections. Satellite glial cells (SGCs) in the dorsal root and trigeminal ganglia of the peripheral nervous system (PNS) and astrocytes in the central nervous system (CNS) express similar molecular markers and are protective under physiological conditions. They also serve similar functions in the genesis and maintenance of neuropathic pain, downregulating some of their homeostatic functions and driving pro-inflammatory neuro-glial interactions in the PNS and CNS, i.e., "gliopathy". However, the role of SGCs in neuropathic pain is not simply as "peripheral astrocytes". We delineate how these peripheral and central glia participate in neuropathic pain by producing different mediators, engaging different parts of neurons, and becoming active at different stages following nerve injury. Finally, we highlight the recent findings that SGCs are enriched with proteins related to fatty acid metabolism and signaling such as Apo-E, FABP7, and LPAR1. Targeting SGCs and astrocytes may lead to novel therapeutics for the treatment of neuropathic pain.
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Affiliation(s)
- Aidan McGinnis
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ru-Rong Ji
- Center for Translational Pain Medicine, Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
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5
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Hu Q, Li G. Role of purinergic receptors in cardiac sympathetic nerve injury in diabetes mellitus. Neuropharmacology 2023; 226:109406. [PMID: 36586475 DOI: 10.1016/j.neuropharm.2022.109406] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 12/13/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022]
Abstract
Diabetic cardiac autonomic neuropathy is a common and serious chronic complication of diabetes, which can lead to sympathetic and parasympathetic nerve imbalance and a relative excitation of the sympathetic nerve. Purinergic receptors play a crucial role in this process. Diabetic cardiac sympathetic nerve injury affects the expression of purinergic receptors, and activated purinergic receptors affect the phosphorylation of different signaling pathways and the regulation of inflammatory processes. This paper introduces the abnormal changes of sympathetic nerve in diabetes mellitus and summarizes the recently published studies on the role of several purinergic receptor subtypes in diabetic cardiac sympathetic nerve injury. These studies suggest that purinergic receptors as novel drug targets are of great significance for the treatment of diabetic autonomic neuropathy. This article is part of the Special Issue on "Purinergic Signaling: 50 years".
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Affiliation(s)
- Qixing Hu
- Department of Physiology, Medical School of Nanchang University, 461 Bayi Road, Nanchang, Jiangxi, 330006, PR China.
| | - Guilin Li
- Department of Physiology, Medical School of Nanchang University, 461 Bayi Road, Nanchang, Jiangxi, 330006, PR China.
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6
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Abstract
Satellite glial cells (SGCs) that surround sensory neurons in the peripheral nervous system ganglia originate from neural crest cells. Although several studies have focused on SGCs, the origin and characteristics of SGCs are unknown, and their lineage remains unidentified. Traditionally, it has been considered that SGCs regulate the environment around neurons under pathological conditions, and perform functions of supporting, nourishing, and protecting neurons. However, recent studies demonstrated that SGCs may have the characteristics of stem cells. After nerve injury, SGCs up-regulate the expression of stem cell markers and can differentiate into functional sensory neurons. Moreover, SGCs express several markers of Schwann cell precursors and Schwann cells, such as CDH19, MPZ, PLP1, SOX10, ERBB3, and FABP7. Schwann cell precursors have also been proposed as a potential source of neurons in the peripheral nervous system. The similarity in function and markers suggests that SGCs may represent a subgroup of Schwann cell precursors. Herein, we discuss the roles and functions of SGCs, and the lineage relationship between SGCs and Schwann cell precursors. We also describe a new perspective on the roles and functions of SGCs. In the DRG located on the posterior root of spinal nerves, satellite glial cells wrap around each sensory neuron to form an anatomically and functionally distinct unit with the sensory neurons. Following nerve injury, satellite glial cells up-regulate the expression of progenitor markers, and can differentiate into neurons.
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7
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Jiang B, Wang J, Liu W, Cheng J, Xu J, Cao M, Li Y. Comparative transcriptome analysis of MDBK cells reveals that BoIFN-γ augmented host immune responses to bovine herpesvirus 1 infection. Front Microbiol 2022; 13:973278. [PMID: 36016774 PMCID: PMC9396027 DOI: 10.3389/fmicb.2022.973278] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Bovine herpesvirus 1 (BoHV-1) is an alphaherpesvirus that causes infectious bovine rhinotracheitis and infectious pustular vulvovaginitis in cattle. Ιnterferon-gamma (IFN-γ) is a pleiotropic cytokine with antiviral activity that modulates the innate and adaptive immune responses. In this study, we prepared high-purity bovine interferon gamma (BoIFN-γ) dimer protein using prokaryotic expression system and affinity chromatography. We subsequently investigated the effect of BoIFN-γ on BoHV-1 infection in Madin-Darby bovine kidney (MDBK) cells. The results showed that BoIFN-γ pre-treament not only decreased the production of BoHV-1 but also reduced the cytopathic effect of the virus. Differential gene expression profiles of BoHV-1 infected MDBK cells were then analysed through high-throughput RNA sequencing. The data showed that BoIFN-γ pre-treatment reduced lipid metabolism disorder and DNA damage caused by BoHV-1 infection. Furthermore, BoIFN-γ treatment upregulated the transcription of interferon regulatory transcription factors (IRF1 and GBP5) and interferon-stimulated genes (ISGs) of MDBK cells. Additionally, BoIFN-γ promotes expression of cellular protein involved in complement activation and coagulation cascades response as well as antigen processing and presentation process, while BoHV-1 infection dramatically downregulates transcription of these immune components including C3, C1r, C1s, PLAT, ITGB2, PROCR, BoLA, CD74, B2M, PA28, BoLA-DRA, and TAPBP. Collectively, our findings revealed that BoIFN-γ pre-treatment can improve host resistance to BoHV-1 infection and regulate transcription or expression of host protein associated with cellular metabolism and innate immune response. This provides insights into the development of prophylactic agents for prevention and control of BoHV-1 infection.
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Affiliation(s)
- Bo Jiang
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
| | - Jing Wang
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
| | - Wenxiao Liu
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
| | - Jing Cheng
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
| | - Jian Xu
- Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Mengyao Cao
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
- Animal Science and Technology College, Beijing University of Agriculture, Beijing, China
| | - Yongqing Li
- Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China
- *Correspondence: Yongqing Li,
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8
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Jager SE, Pallesen LT, Lin L, Izzi F, Pinheiro AM, Villa-Hernandez S, Cesare P, Vaegter CB, Denk F. Comparative transcriptional analysis of satellite glial cell injury response. Wellcome Open Res 2022; 7:156. [PMID: 35950162 PMCID: PMC9329822 DOI: 10.12688/wellcomeopenres.17885.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2022] [Indexed: 11/20/2022] Open
Abstract
Background: Satellite glial cells (SGCs) tightly surround and support primary sensory neurons in the peripheral nervous system and are increasingly recognized for their involvement in the development of neuropathic pain following nerve injury. SGCs are difficult to investigate due to their flattened shape and tight physical connection to neurons in vivo and their rapid changes in phenotype and protein expression when cultured in vitro. Consequently, several aspects of SGC function under normal conditions as well as after a nerve injury remain to be explored. The recent advance in single cell RNA sequencing (scRNAseq) technologies has enabled a new approach to investigate SGCs. Methods: In this study we used scRNAseq to investigate SGCs from mice subjected to sciatic nerve injury. We used a meta-analysis approach to compare the injury response with that found in other published datasets. Furthermore, we also used scRNAseq to investigate how cells from the dorsal root ganglion (DRG) change after 3 days in culture. Results: From our meta-analysis of the injured conditions, we find that SGCs share a common signature of 18 regulated genes following sciatic nerve crush or sciatic nerve ligation, involving transcriptional regulation of cholesterol biosynthesis. We also observed a considerable transcriptional change when culturing SGCs, suggesting that some differentiate into a specialised in vitro state while others start resembling Schwann cell-like precursors. Conclusion: By using integrated analyses of new and previously published scRNAseq datasets, this study provides a consensus view of which genes are most robustly changed in SGCs after injury. Our results are available via the Broad Institute Single Cell Portal, so that readers can explore and search for genes of interest.
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Affiliation(s)
- Sara Elgaard Jager
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Guy's Campus, London, UK
| | - Lone Tjener Pallesen
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus C, Denmark
| | - Lin Lin
- Department of Biomedicine, Aarhus University, Denmark & Steno and Diabetes Center, Aarhus, Denmark
| | - Francesca Izzi
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Tübingen, Germany
| | - Alana Miranda Pinheiro
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus C, Denmark
| | - Sara Villa-Hernandez
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Guy's Campus, London, UK
| | - Paolo Cesare
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Tübingen, Germany
| | - Christian Bjerggaard Vaegter
- Department of Biomedicine, Danish Research Institute of Translational Neuroscience - DANDRITE, Nordic-EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus C, Denmark
| | - Franziska Denk
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King's College London, Guy's Campus, London, UK
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9
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Shin SM, Wang F, Qiu C, Itson-Zoske B, Hogan QH, Yu H. Sigma-1 receptor activity in primary sensory neurons is a critical driver of neuropathic pain. Gene Ther 2022; 29:1-15. [PMID: 32424233 PMCID: PMC7671947 DOI: 10.1038/s41434-020-0157-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 04/21/2020] [Accepted: 05/04/2020] [Indexed: 12/15/2022]
Abstract
The Sigma-1 receptor (σ1R) is highly expressed in the primary sensory neurons (PSNs) that are the critical site of initiation and maintenance of pain following peripheral nerve injury. By immunoblot and immunohistochemistry, we observed increased expression of both σ1R and σ1R-binding immunoglobulin protein (BiP) in the lumbar (L) dorsal root ganglia (DRG) ipsilateral to painful neuropathy induced by spared nerve injury (SNI). To evaluate the therapeutic potential of PSN-targeted σ1R inhibition at a selected segmental level, we designed a recombinant adeno-associated viral (AAV) vector expressing a small hairpin RNA (shRNA) against rat σ1R. Injection of this vector into the L4/L5 DRGs induced downregulation of σ1R in DRG neurons of all size groups, while expression of BiP was not affected. This was accompanied by attenuation of SNI-induced cutaneous mechanical and thermal hypersensitivity. Whole-cell current-clamp recordings of dissociated neurons showed that knockdown of σ1R suppressed neuronal excitability, suggesting that σ1R silencing attenuates pain by reversal of injury-induced neuronal hyperexcitability. These findings support a critical role of σ1R in modulating PSN nociceptive functions, and that the nerve injury-induced elevated σ1R activity in the PSNs can be a significant driver of neuropathic pain. Further understanding the role of PSN-σ1R in pain pathology may open routes to exploit this system for DRG-targeted pain therapy.
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Affiliation(s)
- Seung Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Zablocki Veterans Affairs Medical Center, Milwaukee, WI, 53295, USA
| | - Fei Wang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Medical Experiment Center, Shaanxi University of Chinese Medicine, Xianyang, 712046, Shaanxi, PR China
| | - Chensheng Qiu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, 266000, PR China
| | - Brandon Itson-Zoske
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Quinn H Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Zablocki Veterans Affairs Medical Center, Milwaukee, WI, 53295, USA
| | - Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
- Zablocki Veterans Affairs Medical Center, Milwaukee, WI, 53295, USA.
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10
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Molecular Changes in the Dorsal Root Ganglion during the Late Phase of Peripheral Nerve Injury-induced Pain in Rodents: A Systematic Review. Anesthesiology 2021; 136:362-388. [PMID: 34965284 DOI: 10.1097/aln.0000000000004092] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The dorsal root ganglion is widely recognized as a potential target to treat chronic pain. A fundamental understanding of quantitative molecular and genomic changes during the late phase of pain is therefore indispensable. The authors performed a systematic literature review on injury-induced pain in rodent dorsal root ganglions at minimally 3 weeks after injury. So far, slightly more than 300 molecules were quantified on the protein or messenger RNA level, of which about 60 were in more than one study. Only nine individual sequencing studies were performed in which the most up- or downregulated genes varied due to heterogeneity in study design. Neuropeptide Y and galanin were found to be consistently upregulated on both the gene and protein levels. The current knowledge regarding molecular changes in the dorsal root ganglion during the late phase of pain is limited. General conclusions are difficult to draw, making it hard to select specific molecules as a focus for treatment.
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11
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Huang B, Zdora I, de Buhr N, Eikelberg D, Baumgärtner W, Leitzen E. Phenotypical changes of satellite glial cells in a murine model of G M1 -gangliosidosis. J Cell Mol Med 2021; 26:527-539. [PMID: 34877779 PMCID: PMC8743646 DOI: 10.1111/jcmm.17113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 11/12/2021] [Accepted: 11/25/2021] [Indexed: 12/14/2022] Open
Abstract
Satellite glial cells (SGCs) of dorsal root ganglia (DRG) react in response to various injuries in the nervous system. This study investigates reactive changes within SGCs in a murine model for GM1‐gangliosidosis (GM1). DRG of homozygous β‐galactosidase‐knockout mice and homozygous C57BL/6 wild‐type mice were investigated performing immunostaining on formalin‐fixed, paraffin‐embedded tissue. A marked upregulation of glial fibrillary acidic protein (GFAP), the progenitor marker nestin and Ki67 within SGCs of diseased mice, starting after 4 months at the earliest GFAP, along with intracytoplasmic accumulation of ganglioside within neurons and deterioration of clinical signs was identified. Interestingly, nestin‐positive SGCs were detected after 8 months only. No changes regarding inwardly rectifying potassium channel 4.1, 2, 3‐cyclic nucleotide 3‐phosphodiesterase, Sox2, doublecortin, periaxin and caspase3 were observed in SGCs. Iba1 was only detected in close vicinity of SGCs indicating infiltrating or tissue‐resident macrophages. These results indicate that SGCs of DRG show phenotypical changes during the course of GM1, characterized by GFAP upregulation, proliferation and expression of a neural progenitor marker at a late time point. This points towards an important role of SGCs during neurodegenerative disorders and supports that SGCs represent a multipotent glial precursor cell line with high plasticity and functionality.
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Affiliation(s)
- Bei Huang
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center of Systems Neuroscience, Hannover, Germany
| | - Isabel Zdora
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center of Systems Neuroscience, Hannover, Germany
| | - Nicole de Buhr
- Department of Biochemistry, University of Veterinary Medicine Hannover, Hannover, Germany.,Research Center for Emerging Infections and Zoonoses (RIZ), University of Veterinary Medicine Hannover, Hannover, Germany
| | - Deborah Eikelberg
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Wolfgang Baumgärtner
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.,Center of Systems Neuroscience, Hannover, Germany
| | - Eva Leitzen
- Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany
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12
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Shin SM, Moehring F, Itson-Zoske B, Fan F, Stucky CL, Hogan QH, Yu H. Piezo2 mechanosensitive ion channel is located to sensory neurons and nonneuronal cells in rat peripheral sensory pathway: implications in pain. Pain 2021; 162:2750-2768. [PMID: 34285153 PMCID: PMC8526381 DOI: 10.1097/j.pain.0000000000002356] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 05/18/2021] [Indexed: 11/25/2022]
Abstract
ABSTRACT Piezo2 mechanotransduction channel is a crucial mediator of sensory neurons for sensing and transducing touch, vibration, and proprioception. We here characterized Piezo2 expression and cell specificity in rat peripheral sensory pathway using a validated Piezo2 antibody. Immunohistochemistry using this antibody revealed Piezo2 expression in pan primary sensory neurons of dorsal root ganglia in naïve rats, which was actively transported along afferent axons to both central presynaptic terminals innervating the spinal dorsal horn (DH) and peripheral afferent terminals in the skin. Piezo2 immunoreactivity (IR) was also detected in the postsynaptic neurons of the DH and in the motor neurons of the ventral horn, but not in spinal glial fibrillary acidic protein-positive and Iba1-positive glia. Notably, Piezo2-IR was clearly identified in peripheral nonneuronal cells, including perineuronal glia, Schwann cells in the sciatic nerve and surrounding cutaneous afferent endings, as well as in skin epidermal Merkel cells and melanocytes. Immunoblots showed increased Piezo2 in dorsal root ganglia ipsilateral to plantar injection of complete Freund's adjuvant, and immunostaining revealed increased Piezo2-IR intensity in the DH ipsilateral to complete Freund's adjuvant injection. This elevation of DH Piezo2-IR was also evident in various neuropathic pain models and monosodium iodoacetate knee osteoarthritis pain model, compared with controls. We conclude that (1) the pan neuronal profile of Piezo2 expression suggests that Piezo2 may function extend beyond simply touch or proprioception mediated by large-sized low-threshold mechanosensitive primary sensory neurons; (2) Piezo2 may have functional roles involving sensory processing in the spinal cord, Schwann cells, and skin melanocytes; and (3) aberrant Piezo2 expression may contribute pain pathogenesis.
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Affiliation(s)
- Seung Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Francie Moehring
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Brandon Itson-Zoske
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Fan Fan
- Department of Pharmacology and Toxicology, Mississippi University Medical Center, Jackson, Mississippi 39216
| | - Cheryl L. Stucky
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Quinn H. Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226
- Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295
| | - Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI 53226
- Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295
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13
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Hemmat N, Asadzadeh H, Asadzadeh Z, Shadbad MA, Baradaran B. The Analysis of Herpes Simplex Virus Type 1 (HSV-1)-Encoded MicroRNAs Targets: A Likely Relationship of Alzheimer's Disease and HSV-1 Infection. Cell Mol Neurobiol 2021; 42:2849-2861. [PMID: 34661780 DOI: 10.1007/s10571-021-01154-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/01/2021] [Indexed: 10/20/2022]
Abstract
Alzheimer's disease (AD), the most frequently diagnosed dementia, is a senile neurodegenerative disorder characterized by amnesia and cognitive dysfunction. Unfortunately, there are still no successful strategies to prevent AD progression. Thus, the vast majority of research focuses on recognizing risk factors for developing and progressing this disease. Human spirochetes, fungi, Borrelia burgdorferi, Chlamydophila pneumoniae, Helicobacter pylori, and human herpes simplex virus type 1 (HSV-1) have all been implicated in the development and progression of AD. Identifying microRNAs (miRs) encoded by DNA viruses has indicated that viruses can be evolved to exploit RNA silencing to regulate host and viral genes. Similar to host miR, v-miR can interact with the 3' untranslated region (UTR) of the target mRNA to regulate gene expression. Although HSV-1 can also encode various miRs, their significance in the development and progression of AD is still unclear. In the present study, utilizing the bioinformatics approach (R software and related packages), we analyzed the differentially expressed genes (DEGs) in AD samples (grey matter) of GSE37263 dataset obtained from the NCBI Gene Expression Omnibus (GEO). Then, the sequences of HSV-1-encoded-miRs were retrieved from miRbase, and their targets were predicted by miRDB. Afterward, the common genes between downregulated DEGs in AD and targets of HSV-1-encoded miRs were identified to shed new light on the relationship between HSV-1 infection and AD development. Our results have indicated that HSV-1-encoded-miRs can target the downregulated DEGs in AD, and these aberrant interactions can offer valuable diagnostic/prognostic biomarkers for affected patients.
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Affiliation(s)
- Nima Hemmat
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Haniyeh Asadzadeh
- Department of Psychology, Ardabil Branch of Islamic Azad University, Ardabil, Iran
| | - Zahra Asadzadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahdi Abdoli Shadbad
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Behzad Baradaran
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
- Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
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14
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Liśkiewicz D, Liśkiewicz A, Nowacka-Chmielewska MM, Grabowski M, Pondel N, Grabowska K, Student S, Barski JJ, Małecki A. Differential Response of Hippocampal and Cerebrocortical Autophagy and Ketone Body Metabolism to the Ketogenic Diet. Front Cell Neurosci 2021; 15:733607. [PMID: 34456688 PMCID: PMC8385303 DOI: 10.3389/fncel.2021.733607] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 07/21/2021] [Indexed: 11/13/2022] Open
Abstract
Experimental and clinical data support the neuroprotective properties of the ketogenic diet and ketone bodies, but there is still a lot to discover to comprehensively understand the underlying mechanisms. Autophagy is a key mechanism for maintaining cell homeostasis, and therefore its proper function is necessary for preventing accelerated brain aging and neurodegeneration. Due to many potential interconnections, it is possible that the stimulation of autophagy may be one of the mediators of the neuroprotection afforded by the ketogenic diet. Recent studies point to possible interconnections between ketone body metabolism and autophagy. It has been shown that autophagy is essential for hepatic and renal ketogenesis in starvation. On the other hand, exogenous ketone bodies modulate autophagy both in vitro and in vivo. Many regional differences occur between brain structures which concern i.e., metabolic responses and autophagy dynamics. The aim of the present study was to evaluate the influence of the ketogenic diet on autophagic markers and the ketone body utilizing and transporting proteins in the hippocampus and frontal cortex. C57BL/6N male mice were fed with two ketogenic chows composed of fat of either animal or plant origins for 4 weeks. Markers of autophagosome formation as well as proteins associated with ketolysis (BDH1-3-hydroxybutyrate dehydrogenase 1, SCOT/OXCT1-succinyl CoA:3-oxoacid CoA transferase), ketone transport (MCT1-monocarboxylate transporter 1) and ketogenesis (HMGCL, HMGCS2) were measured. The hippocampus showed a robust response to nutritional ketosis in both changes in the markers of autophagy as well as the levels of ketone body utilizing and transporting proteins, which was also accompanied by increased concentrations of ketone bodies in this brain structure, while subtle changes were observed in the frontal cortex. The magnitude of the effects was dependent on the type of ketogenic diet used, suggesting that plant fats may exert a more profound effect on the orchestrated upregulation of autophagy and ketone body metabolism markers. The study provides a foundation for a deeper understanding of the possible interconnections between autophagy and the neuroprotective efficacy of nutritional ketosis.
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Affiliation(s)
- Daniela Liśkiewicz
- Laboratory of Molecular Biology, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | - Arkadiusz Liśkiewicz
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Marta M Nowacka-Chmielewska
- Laboratory of Molecular Biology, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | - Mateusz Grabowski
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland.,Department for Experimental Medicine, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Natalia Pondel
- Laboratory of Molecular Biology, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
| | - Konstancja Grabowska
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland.,Department for Experimental Medicine, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Sebastian Student
- Institute of Automatic Control, Silesian University of Technology, Gliwice, Poland.,Biotechnology Centre, Silesian University of Technology, Gliwice, Poland
| | - Jaroslaw J Barski
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland.,Department for Experimental Medicine, Faculty of Medical Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | - Andrzej Małecki
- Laboratory of Molecular Biology, Institute of Physiotherapy and Health Sciences, The Jerzy Kukuczka Academy of Physical Education, Katowice, Poland
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15
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Discrepancy in the Usage of GFAP as a Marker of Satellite Glial Cell Reactivity. Biomedicines 2021; 9:biomedicines9081022. [PMID: 34440226 PMCID: PMC8391720 DOI: 10.3390/biomedicines9081022] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/04/2021] [Accepted: 08/11/2021] [Indexed: 12/13/2022] Open
Abstract
Satellite glial cells (SGCs) surrounding the neuronal somas in peripheral sensory ganglia are sensitive to neuronal stressors, which induce their reactive state. It is believed that such induced gliosis affects the signaling properties of the primary sensory neurons and is an important component of the neuropathic phenotype leading to pain and other sensory disturbances. Efforts to understand and manipulate such gliosis relies on reliable markers to confirm induced SGC reactivity and ultimately the efficacy of targeted intervention. Glial fibrillary acidic protein (GFAP) is currently the only widely used marker for such analyses. However, we have previously described the lack of SGC upregulation of GFAP in a mouse model of sciatic nerve injury, suggesting that GFAP may not be a universally suitable marker of SGC gliosis across species and experimental models. To further explore this, we here investigate the regulation of GFAP in two different experimental models in both rats and mice. We found that whereas GFAP was upregulated in both rodent species in the applied inflammation model, only the rat demonstrated increased GFAP in SGCs following sciatic nerve injury; we did not observe any such GFAP upregulation in the mouse model at either protein or mRNA levels. Our results demonstrate an important discrepancy between species and experimental models that prevents the usage of GFAP as a universal marker for SGC reactivity.
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16
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Shin SM, Itson-Zoske B, Cai Y, Qiu C, Pan B, Stucky CL, Hogan QH, Yu H. Satellite glial cells in sensory ganglia express functional transient receptor potential ankyrin 1 that is sensitized in neuropathic and inflammatory pain. Mol Pain 2021; 16:1744806920925425. [PMID: 32484015 PMCID: PMC7268132 DOI: 10.1177/1744806920925425] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Transient receptor potential ankyrin 1 (TRPA1) is well documented as an important molecule in pain hypersensitivity following inflammation and nerve injury and in many other cellular biological processes. Here, we show that TRPA1 is expressed not only by sensory neurons of the dorsal root ganglia (DRG) but also in their adjacent satellite glial cells (SGCs), as well as nonmyelinating Schwann cells. TRPA1 immunoreactivity is also detected in various cutaneous structures of sensory neuronal terminals, including small and large caliber cutaneous sensory fibers and endings. The SGC-expressed TRPA1 is functional. Like DRG neurons, dissociated SGCs exhibit a robust response to the TRPA1-selective agonist allyl isothiocyanate (AITC) by an increase of intracellular Ca2+ concentration ([Ca2+]i). These responses are abolished by the TRPA1 antagonist HC030031 and are absent in SGCs and neurons from global TRPA1 null mice. SGCs and neurons harvested from DRG proximal to painful tissue inflammation induced by plantar injection of complete Freund’s adjuvant show greater AITC-evoked elevation of [Ca2+]i and slower recovery compared to sham controls. Similar TRPA1 sensitization occurs in both SGCs and neurons during neuropathic pain induced by spared nerve injury. Together, these results show that functional TRPA1 is expressed by sensory ganglia SGCs, and TRPA1 function in SGCs is enhanced after both peripheral inflammation and nerve injury, and suggest that TRPA1 in SGCs may contribute to inflammatory and neuropathic pain.
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Affiliation(s)
- Seung Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Clement J. Zablocki VA Medical Center, Milwaukee, WI, USA
| | - Brandon Itson-Zoske
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Yongsong Cai
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Xi'an Jiaotong University Health Science Center, Xi'an, P.R. China
| | - Chensheng Qiu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, P.R. China
| | - Bin Pan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Cheryl L Stucky
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Quinn H Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Clement J. Zablocki VA Medical Center, Milwaukee, WI, USA
| | - Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Clement J. Zablocki VA Medical Center, Milwaukee, WI, USA
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17
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Wang T, Zhang Y, Chen W, Tao J, Xue Q, Ge W, Dou W, Ma C. Proteomic changes in the hippocampus and motor cortex in a rat model of cerebral palsy: Effects of topical treatment. Biomed Pharmacother 2021; 133:110844. [PMID: 33186793 DOI: 10.1016/j.biopha.2020.110844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 09/21/2020] [Accepted: 10/04/2020] [Indexed: 11/21/2022] Open
Abstract
Cerebral palsy (CP) is a non-progressive motor-impairment disorder related to brain injury early in development. To gain new insights into the mechanisms of CP and the therapeutic efficacy of Baimai ointment, we used a high-throughput quantitative proteomic approach to evaluate proteomic changes in the hippocampus and motor cortex in a rat model of CP induced by lipopolysaccharide (LPS) combined with hypoxia/ischemia (H/I). More than 2000 proteins were identified in each brain region with high confidence. Quantitative analysis demonstrated profound disturbances in the proteomes of the hippocampus and motor cortex after LPS + H/I, in addition to the disruption of the motor system. In contrast, the topical application of Baimai ointment not only alleviated the motor deficit in the CP model rats, but also restored the proteomes in the brain cortex. Furthermore, astrocytes in the hippocampus were strongly activated in the Baimai-treated CP rat brains, associated with an increase in neurotrophic factors. Proteomic analysis demonstrated that the CP model induced neuroinflammatory responses in the brain which were reversed by the topical application of Baimai ointment. This study highlights the unexpected roles of hippocampus and motor cortex neurons in CP progress and treatment, thus providing potentially novel therapeutic targets for CP.
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Affiliation(s)
- Tao Wang
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Department of Human Anatomy, Histology and Embryology, Neuroscience Center, Joint Laboratory of Anesthesia and Pain, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing 100005, China
| | - Yusheng Zhang
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, 5 Dong Dan San Tiao, Dongcheng District, Beijing 100005, China
| | - Weiwu Chen
- School of Business Administration, Shenyang Pharmaceutical University, Shenyang, China
| | - Jin Tao
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Department of Human Anatomy, Histology and Embryology, Neuroscience Center, Joint Laboratory of Anesthesia and Pain, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing 100005, China
| | - Qiao Xue
- Tibet Cheezheng Tibetan Medicine Co., Ltd., Beijing, China
| | - Wei Ge
- National Key Laboratory of Medical Molecular Biology & Department of Immunology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, 5 Dong Dan San Tiao, Dongcheng District, Beijing 100005, China
| | - Wanchen Dou
- Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
| | - Chao Ma
- Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Department of Human Anatomy, Histology and Embryology, Neuroscience Center, Joint Laboratory of Anesthesia and Pain, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing 100005, China.
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18
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Jager SE, Pallesen LT, Richner M, Harley P, Hore Z, McMahon S, Denk F, Vaegter CB. Changes in the transcriptional fingerprint of satellite glial cells following peripheral nerve injury. Glia 2020; 68:1375-1395. [PMID: 32045043 DOI: 10.1002/glia.23785] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 01/13/2023]
Abstract
Satellite glial cells (SGCs) are homeostatic cells enveloping the somata of peripheral sensory and autonomic neurons. A wide variety of neuronal stressors trigger activation of SGCs, contributing to, for example, neuropathic pain through modulation of neuronal activity. However, compared to neurons and other glial cells of the nervous system, SGCs have received modest scientific attention and very little is known about SGC biology, possibly due to the experimental challenges associated with studying them in vivo and in vitro. Utilizing a recently developed method to obtain SGC RNA from dorsal root ganglia (DRG), we took a systematic approach to characterize the SGC transcriptional fingerprint by using next-generation sequencing and, for the first time, obtain an overview of the SGC injury response. Our RNA sequencing data are easily accessible in supporting information in Excel format. They reveal that SGCs are enriched in genes related to the immune system and cell-to-cell communication. Analysis of SGC transcriptional changes in a nerve injury-paradigm reveal a differential response at 3 days versus 14 days postinjury, suggesting dynamic modulation of SGC function over time. Significant downregulation of several genes linked to cholesterol synthesis was observed at both time points. In contrast, regulation of gene clusters linked to the immune system (MHC protein complex and leukocyte migration) was mainly observed after 14 days. Finally, we demonstrate that, after nerve injury, macrophages are in closer physical proximity to both small and large DRG neurons, and that previously reported injury-induced proliferation of SGCs may, in fact, be proliferating macrophages.
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Affiliation(s)
- Sara E Jager
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus C, Denmark.,Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London, UK
| | - Lone T Pallesen
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Mette Richner
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Peter Harley
- Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London, UK
| | - Zoe Hore
- Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London, UK
| | - Stephen McMahon
- Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London, UK
| | - Franziska Denk
- Wolfson Centre for Age-Related Diseases, King's College London, Guy's Campus, London, UK
| | - Christian B Vaegter
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic-EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, Aarhus C, Denmark
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19
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Zhang Q, Zhao J, Shen J, Zhang X, Ren R, Ma Z, He Y, Kang Q, Wang Y, Dong X, Sun J, Liu Z, Yi X. The ATP-P2X7 Signaling Pathway Participates in the Regulation of Slit1 Expression in Satellite Glial Cells. Front Cell Neurosci 2019; 13:420. [PMID: 31607866 PMCID: PMC6761959 DOI: 10.3389/fncel.2019.00420] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/02/2019] [Indexed: 11/17/2022] Open
Abstract
Slit1 is one of the known signaling factors of the slit family and can promote neurite growth by binding to its receptor, Robo2. Upregulation of Slit1 expression in dorsal root ganglia (DRG) after peripheral nerve injury plays an important role in nerve regeneration. Each sensory neuronal soma in the DRG is encapsulated by several surrounding satellite glial cells (SGCs) to form a neural structural unit. However, the temporal and spatial patterns of Slit1 upregulation in SGCs in DRG and its molecular mechanisms are not well understood. This study examined the spatial and temporal patterns of Slit1 expression in DRG after sciatic nerve crush by immunohistochemistry and western blotting. The effect of neuronal damage signaling on the expression of Slit1 in SGCs was studied in vivo by fluorescent gold retrograde tracing and double immunofluorescence staining. The relationship between the expression of Slit1 in SGCs and neuronal somas was also observed by culturing DRG cells and double immunofluorescence labeling. The molecular mechanism of Slit1 was further explored by immunohistochemistry and western blotting after intraperitoneal injection of Bright Blue G (BBG, P2X7R inhibitor). The results showed that after peripheral nerve injury, the expression of Slit1 in the neurons and SGCs of DRG increased. The expression of Slit1 was presented with a time lag in SGCs than in neurons. The expression of Slit1 in SGCs was induced by contact with surrounding neuronal somas. Through injured cell localization, it was found that the expression of Slit1 was stronger in SGCs surrounding injured neurons than in SGCs surrounding non-injured neurons. The expression of vesicular nucleotide transporter (VNUT) in DRG neurons was increased by injury signaling. After the inhibition of P2X7R, the expression of Slit1 in SGCs was downregulated, and the expression of VNUT in DRG neurons was upregulated. These results indicate that the ATP-P2X7R pathway is involved in signal transduction from peripheral nerve injury to SGCs, leading to the upregulation of Slit1 expression.
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Affiliation(s)
- Quanpeng Zhang
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Jiuhong Zhao
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Jing Shen
- Department of Ophthalmology, First Affiliated Hospital of Hainan Medical University, Haikou, China
| | - Xianfang Zhang
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Rui Ren
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Zhijian Ma
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Yuebin He
- Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
| | - Qian Kang
- Infection Control Department, People's Hospital of Xing'an County, Guilin, China
| | - Yanshan Wang
- Quality Inspection Department, Minghui Industry (Shenzhen) Co., Ltd., Shenzhen, China
| | - Xu Dong
- Hainan Provincial Key Laboratory of Carcinogenesis and Intervention, Hainan Medical University, Haikou, China
| | - Jin Sun
- Department of Clinical Medicine, Hainan Medical University, Haikou, China
| | - Zhuozhou Liu
- Department of Clinical Medicine, Hainan Medical University, Haikou, China
| | - Xinan Yi
- Department of Anatomy, Hainan Medical University, Haikou, China.,Joint Laboratory for Neuroscience, Hainan Medical University, Fourth Military Medical University, Haikou, China
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20
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Metwally E, Farouk SM, Osman AHK. Molecular cloning and cellular expression of the cholesterol synthesizing enzymes during the prenatal development of the optic nerve in the dromedary camel (Camelus Dromedarius). Acta Histochem 2019; 121:584-594. [PMID: 31079945 DOI: 10.1016/j.acthis.2019.05.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 04/23/2019] [Accepted: 05/03/2019] [Indexed: 10/26/2022]
Abstract
The Cholesterol-synthesizing proteins (HMGCS1 and HMGCS2) are mitochondrial enzymes that believed to catalyze the first reaction of ketogenesis, the process by which energy is provided from fats in the absence of carbohydrates. Typically, astrocytes developed from its progenitor cells in the embryonic optic nerve and enriched with HMGCS1 and 2. However, the detailed histomorphology of camel HMGCS1 and 2 remains to be clearly defined. Here, we investigated the changes that associate with astrocytes differentiation within the developing camel optic nerve. Firstly, we isolated cDNAs encoding HMGCS1 and 2 from the optic nerve. Then, we found that HMGCS1 shared high similarity to human, while HMGCS2 showed a lower similarity and was more diverse. Immunohistochemical studies revealed that distinct correlation of astrocytes differentiation with HMGCS1 and 2 expressions in the developing camel optic nerve. Both encoded proteins were localized throughout the cytoplasm, as well as the nuclei of the astrocytes. In addition, semi-quantitative PCR analysis and western analysis confirmed that both HMGCS1 and 2 were highly expressed in camel optic nerve as well as other tissue, but they were lower in both skeletal and heart muscles. Moreover, various stains such as Sudan black and florescence filipin stains were used to visualize the free cholesterol in the astrocytes, indicating the enzymatic activity of HMGCS1 and 2. Together, our study reported the first comprehensive investigation of the molecular cloning and cellular expression of HMGCS1 and 2 in the optic nerve of dromedary camel.
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21
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Wang XB, Ma W, Luo T, Yang JW, Wang XP, Dai YF, Guo JH, Li LY. A novel primary culture method for high-purity satellite glial cells derived from rat dorsal root ganglion. Neural Regen Res 2019; 14:339-345. [PMID: 30531018 PMCID: PMC6301172 DOI: 10.4103/1673-5374.244797] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Satellite glial cells surround neurons within dorsal root ganglia. Previous studies have focused on single-cell suspensions of cultured neurons derived from rat dorsal root ganglia. At present, the primary culture method for satellite glial cells derived from rat dorsal root ganglia requires no digestion skill. Hence, the aim of the present study was to establish a novel primary culture method for satellite glial cells derived from dorsal root ganglia. Neonatal rat spine was collected and an incision made to expose the transverse protrusion and remove dorsal root ganglia. Dorsal root ganglia were freed from nerve fibers, connective tissue, and capsule membranes, then rinsed and transferred to 6-well plates, and cultured in a humidified 5% CO2 incubator at 37°C. After 3 days in culture, some cells had migrated from dorsal root ganglia. After subculture, cells were identified by immunofluorescence labeling for three satellite glial cell-specific markers: glutamine synthetase, glial fibrillary acidic protein, and S100β. Cultured cells expressed glutamine synthetase, glial fibrillary acidic protein, and S100β, suggesting they are satellite glial cells with a purity of > 95%. Thus, we have successfully established a novel primary culture method for obtaining high-purity satellite glial cells from rat dorsal root ganglia without digestion.
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Affiliation(s)
- Xian-Bin Wang
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province, China
| | - Wei Ma
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province, China
| | - Tao Luo
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province; Medical Faculty, Panzhihua University, Panzhihua, Sichuan Province, China
| | - Jin-Wei Yang
- Institute of Neuroscience, Kunming Medical University; Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan Province, China
| | - Xiang-Peng Wang
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province, China
| | - Yun-Fei Dai
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province, China
| | - Jian-Hui Guo
- Second Department of General Surgery, First People's Hospital of Yunnan Province, Kunming, Yunnan Province, China
| | - Li-Yan Li
- Institute of Neuroscience, Kunming Medical University, Kunming, Yunnan Province, China
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22
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Yu H, Shin SM, Wang F, Xu H, Xiang H, Cai Y, Itson-Zoske B, Hogan QH. Transmembrane protein 100 is expressed in neurons and glia of dorsal root ganglia and is reduced after painful nerve injury. Pain Rep 2018; 4:e703. [PMID: 30801043 PMCID: PMC6370145 DOI: 10.1097/pr9.0000000000000703] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 10/08/2018] [Accepted: 10/30/2018] [Indexed: 12/16/2022] Open
Abstract
Introduction Tmem100 modulates interactions between TRPA1 and TRPV1. The cell specificity of Tmem100 expression in dorsal root ganglia (DRGs) is not well defined, nor is the effect of peripheral nerve injury on Tmem100 expression. Objective This study was designed to determine the cell specificity of Tmem100 expression in DRG and its subcellular localization, and to examine how Tmem100 expression may be altered in painful conditions. Methods Dorsal root ganglion Tmem100 expression was determined by immunohistochemistry, immunoblot, and quantitative real-time PCR, and compared between various experimental rat pain models and controls. Results Tmem100 is expressed in both neurons and perineuronal glial cells in the rat DRG. The plasma membrane and intracellular localization of Tmem100 are identified in 83% ± 6% of IB4-positive and 48% ± 6% of calcitonin gene-related peptide-positive neurons, as well as in medium- and large-sized neurons, with its immunopositivity colocalized to TRPV1 (94% ± 5%) and TRPA1 (96% ± 3%). Tmem100 is also detected in the perineuronal satellite glial cells and in some microglia. Tmem100 protein is significantly increased in the lumbar DRGs in the complete Freund adjuvant inflammatory pain. By contrast, peripheral nerve injury by spinal nerve ligation diminishes Tmem100 expression in the injured DRG, with immunoblot and immunohistochemistry experiments showing reduced Tmem100 protein levels in both neurons and satellite glial cells of DRGs proximal to injury, whereas Tmem100 is unchanged in adjacent DRGs. The spared nerve injury model also reduces Tmem100 protein in the injured DRGs. Conclusion Our data demonstrate a pain pathology-dependent alteration of DRG Tmem100 protein expression, upregulated during CFA inflammatory pain but downregulated during neuropathic pain.
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Affiliation(s)
- Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA
| | - Seung Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Fei Wang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Medical Experiment Center, Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, PR of China
| | - Hao Xu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, PR of China
| | - Hongfei Xiang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, PR of China
| | - Yongsong Cai
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, PR of China
| | - Brandon Itson-Zoske
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Quinn H Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, WI, USA.,Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA
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23
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Shao X, Tang Y, Long H, Gu H, Zhang J, Deng P, Zhao Y, Cen X. HMG-CoA synthase 2 drives brain metabolic reprogramming in cocaine exposure. Neuropharmacology 2017; 148:377-393. [PMID: 28987936 DOI: 10.1016/j.neuropharm.2017.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 09/25/2017] [Accepted: 10/01/2017] [Indexed: 02/05/2023]
Abstract
The brain is a high energy-consuming organ that typically utilizes glucose as the main energy source for cerebral activity. When glucose becomes scarce under conditions of stress, ketone bodies, such as β-hydroxybutyrate, acetoacetate and acetone, become extremely important. Alterations in brain energy metabolism have been observed in psychostimulant abusers; however, the mode of brain metabolic programming in cocaine dependence remains largely unknown. Here, we profiled the metabolites and metabolic enzymes from brain nucleus accumbens (NAc) of mice exposed to cocaine. We found that cocaine modified energy metabolism and markedly activated ketogenesis pathway in the NAc. The expression of HMG-CoA synthase 2 (HMGCS2), a critical rate-limiting ketogenesis enzyme, was markedly up-regulated. After switching metabolic pathways from ketogenesis to glycolysis through activation of glucokinase, cocaine-evoked metabolic reprogramming regained homeostasis, and the cocaine effect was attenuated. Importantly, both the pharmacological and genetic inhibition of HMGCS2 significantly suppressed cocaine-induced ketogenesis and behavior. In conclusion, cocaine induces a remarkable energy reprogramming in the NAc, which is characterized by HMGCS2-driven ketogenesis. Such effect may facilitate adaptations to cocaine-induced energy stress in the brain. Our findings establish an important link between drug-induced energy reprogramming and cocaine effect, and may have implication in the treatment of cocaine addiction.
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Affiliation(s)
- Xue Shao
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China
| | - Yunxuan Tang
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China
| | - Hailei Long
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China
| | - Hui Gu
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China
| | - Jie Zhang
- Key Laboratory of Transplant Engineering and Immunology, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Pengchi Deng
- Analytical &Testing Center, Sichuan University, Chengdu 610041, China
| | - Yinglan Zhao
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China
| | - Xiaobo Cen
- National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center for Biotherapy, Chengdu 610041, PR China.
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24
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Xiang H, Xu H, Fan F, Shin SM, Hogan QH, Yu H. Glial fibrillary acidic protein promoter determines transgene expression in satellite glial cells following intraganglionic adeno-associated virus delivery in adult rats. J Neurosci Res 2017; 96:436-448. [PMID: 28941260 DOI: 10.1002/jnr.24183] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/25/2017] [Accepted: 09/05/2017] [Indexed: 12/24/2022]
Abstract
Recombinant adeno-associated viral (AAV)-mediated therapeutic gene transfer to dorsal root ganglia (DRG) is an effective and safe tool for treating chronic pain. However, AAV with various constitutively active promoters leads to transgene expression predominantly to neurons, while glial cells are refractory to AAV transduction in the peripheral nervous system. The present study evaluated whether in vivo satellite glial cell (SGC) transduction in the DRG can be enhanced by the SGC-specific GFAP promoter and by using shH10 and shH19, which are engineered capsid variants with Müller glia-prone transduction. Titer-matched AAV6 (as control), AAVshH10, and AAVshH19, all encoding the EGFP driven by the constitutively active CMV promoter, as well as AAV6-EGFP and AAVshH10-EGFP driven by a GFAP promoter (AAV6-GFAP-EGFP and AAVshH10-GFAP-EGFP), were injected into DRG of adult male rats. Neurotropism of gene expression was determined and compared by immunohistochemistry. Results showed that injection of AAV6- and AAVshH10-GFAP-EGFP induces robust EGFP expression selectively in SGCs, whereas injection of either AAVshH10-CMV-EGFP or AAVshH19-CMV-EGFP into DRG resulted in a similar in vivo transduction profile to AAV6-CMV-EGFP, all showing efficient transduction of sensory neurons without significant transduction of glial cell populations. Coinjection of AAV6-CMV-mCherry and AAV6-GFAP-EGFP induces transgene expression in neurons and SGCs separately. This report, together with our prior studies, demonstrates that the GFAP promoter rather than capsid tropism determines selective gene expression in SGCs following intraganglionic AAV delivery in adult rats. A dual AAV system, one with GFAP promoter and the other with CMV promoter, can efficiently express transgenes selectively in neurons versus SGCs.
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Affiliation(s)
- Hongfei Xiang
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, People's Republic of China
| | - Hao Xu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Department of Orthopedic Surgery, Affiliated Hospital of Qingdao University, Qingdao, People's Republic of China
| | - Fan Fan
- Department of Pharmacology and Toxicology, Mississippi University Medical Center, Jackson, Mississippi
| | - Seung-Min Shin
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Quinn H Hogan
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin
| | - Hongwei Yu
- Department of Anesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin.,Zablocki Veterans Affairs Medical Center, Milwaukee, Wisconsin
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25
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Swayne LA, Boyce AKJ. Regulation of Pannexin 1 Surface Expression by Extracellular ATP: Potential Implications for Nervous System Function in Health and Disease. Front Cell Neurosci 2017; 11:230. [PMID: 28848396 PMCID: PMC5550711 DOI: 10.3389/fncel.2017.00230] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 07/24/2017] [Indexed: 02/02/2023] Open
Abstract
Pannexin 1 (Panx1) channels are widely recognized for their role in ATP release, and as follows, their function is closely tied to that of ATP-activated P2X7 purinergic receptors (P2X7Rs). Our recent work has shown that extracellular ATP induces clustering of Panx1 with P2X7Rs and their subsequent internalization through a non-canonical cholesterol-dependent mechanism. In other words, we have demonstrated that extracellular ATP levels can regulate the cell surface expression of Panx1. Here we discuss two situations in which we hypothesize that ATP modulation of Panx1 surface expression could be relevant for central nervous system function. The first scenario involves the development of new neurons in the ventricular zone. We propose that ATP-induced Panx1 endocytosis could play an important role in regulating the balance of cell proliferation, survival, and differentiation within this neurogenic niche in the healthy brain. The second scenario relates to the spinal cord, in which we posit that an impairment of ATP-induced Panx1 endocytosis could contribute to pathological neuroplasticity. Together, the discussion of these hypotheses serves to highlight important outstanding questions regarding the interplay between extracellular ATP, Panx1, and P2X7Rs in the nervous system in health and disease.
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Affiliation(s)
- Leigh A Swayne
- Division of Medical Sciences and Island Medical Program, University of Victoria, VictoriaBC, Canada.,Department of Cellular and Physiological Sciences, University of British Columbia, VancouverBC, Canada
| | - Andrew K J Boyce
- Division of Medical Sciences and Island Medical Program, University of Victoria, VictoriaBC, Canada
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