Next Article in Journal
The Effect of Adjuvant Therapy with Molecular Hydrogen on Endogenous Coenzyme Q10 Levels and Platelet Mitochondrial Bioenergetics in Patients with Non-Alcoholic Fatty Liver Disease
Next Article in Special Issue
The Germinal Origin of Salivary and Lacrimal Glands and the Contributions of Neural Crest Cell-Derived Epithelium to Tissue Regeneration
Previous Article in Journal
New Clinical and Immunofluorescence Data of Collagen VI-Related Myopathy: A Single Center Cohort of 69 Patients
Previous Article in Special Issue
The Emerging Roles of the Cephalic Neural Crest in Brain Development and Developmental Encephalopathies
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Review

Harnessing the Power of Enteric Glial Cells’ Plasticity and Multipotency for Advancing Regenerative Medicine

by
Marie A. Lefèvre
1,2,
Rodolphe Soret
1,2,* and
Nicolas Pilon
1,2,3,*
1
Département des Sciences Biologiques, Université du Québec à Montréal (UQAM), Montreal, QC H3C 3P8, Canada
2
Centre D’excellence en Recherche Sur Les Maladies Orphelines—Fondation Courtois (CERMO-FC), Université du Québec à Montréal, Montreal, QC H2X 3Y7, Canada
3
Département de Pédiatrie, Université de Montréal, Montreal, QC H3T 1C5, Canada
*
Authors to whom correspondence should be addressed.
Int. J. Mol. Sci. 2023, 24(15), 12475; https://doi.org/10.3390/ijms241512475
Submission received: 20 June 2023 / Revised: 31 July 2023 / Accepted: 3 August 2023 / Published: 5 August 2023
(This article belongs to the Special Issue Neural Crest Development in Health and Disease (Volume 2))

Abstract

:
The enteric nervous system (ENS), known as the intrinsic nervous system of the gastrointestinal tract, is composed of a diverse array of neuronal and glial cell subtypes. Fascinating questions surrounding the generation of cellular diversity in the ENS have captivated ENS biologists for a considerable time, particularly with recent advancements in cell type-specific transcriptomics at both population and single-cell levels. However, the current focus of research in this field is predominantly restricted to the study of enteric neuron subtypes, while the investigation of enteric glia subtypes significantly lags behind. Despite this, enteric glial cells (EGCs) are increasingly recognized as equally important regulators of numerous bowel functions. Moreover, a subset of postnatal EGCs exhibits remarkable plasticity and multipotency, distinguishing them as critical entities in the context of advancing regenerative medicine. In this review, we aim to provide an updated overview of the current knowledge on this subject, while also identifying key questions that necessitate future exploration.

1. Introduction

The enteric nervous system (ENS) is the most complex division of the peripheral nervous system [1,2], being composed of thousands of interconnected ganglia that contain variable numbers of neurons and glia. In mammals, these ganglia are organized into two interconnected networks known as the myenteric plexus and the submucosal plexus. The myenteric plexus is located between the longitudinal and circular muscle layers of the gastrointestinal tract, and is thereby responsible for regulating mixing and peristaltic patterns of contraction and relaxation. From its position under the mucosa, the submucosal plexus instead regulates various epithelial functions, including selective permeability [2,3]. It is also noteworthy that the ENS interacts bilaterally with both the immune system and the microbiota [4,5,6,7,8,9]. Moreover, while the ENS largely operates independently of the central nervous system, it plays a crucial role in facilitating bidirectional gut-brain communication via extrinsic afferent and efferent nerves of the vagal, spinal/sympathetic and pelvic pathways [10,11].
The diverse range of gastrointestinal functions controlled by the ENS can be partially attributed to the similarly wide variety of enteric neuron subtypes, with more than 20 functional classes identified in mammals [12,13,14]. For instance, smooth muscle contraction and relaxation are mainly regulated by cholinergic (excitatory) and nitrergic (inhibitory) neuron subtypes, respectively. However, it is also necessary to acknowledge the importance of enteric glial cells (EGCs) in the regulation of several bowel functions [15,16,17]. A growing body of evidence even suggests that some of the key functions attributed to the ENS are in fact primarily performed by EGCs. In particular, recent studies convincingly demonstrate that EGCs can directly control gastrointestinal immunity [18] and epithelial integrity [19], notably by sensing insults/damages and subsequently releasing relevant pro-resolution diffusible factors [9,20,21,22].
Currently, up to nine subtypes of EGCs can be distinguished in the mature mammalian ENS based on morphological/topological (Table 1 and Figure 1), functional (Table 2) or transcriptional (Table 3) criteria. As for enteric neuron subtypes, such diversity strongly suggests that EGCs regulate specific gastrointestinal functions in a subtype-dependent manner, but this question is only beginning to be addressed. As cell-based therapies are increasingly being considered for treating various gastrointestinal conditions, it has also become mandatory to begin studying the mechanisms of EGC formation and diversification in the mammalian ENS. This is especially important when considering the plasticity and multipotency exhibited by some EGCs. In this review, we summarize the most relevant findings along all these lines and identify what we think are the most urgent needs for future research.

2. The ENS Is Built from Multiple Progenitors

Based on several studies using various model organisms, there is a large consensus that most of the ENS is derived from neural crest cells (NCCs)—a vertebrate-specific population of multipotent embryonic cells named in reference to their initial accumulation in the dorsal midline of the developing neural tube. According to their location along the anterior–posterior axis, NCCs can be subdivided into four main subpopulations (from anterior to posterior): cranial, vagal, trunk and sacral. Each of these four subpopulations have distinctive differentiation potential and migratory pattern from the dorsal neural tube [32,33]. Three of them (vagal, trunk and sacral) are a source of ENS progenitors, with vagal NCCs being responsible for generating the majority of enteric neurons and glia [33,34,35,36,37,38]. In mice, vagal NCCs first invade the foregut mesenchyme around embryonic day (e) 9.5 and then migrate posteriorly toward the hindgut to reach the prospective rectum around e14.5 [39]. Sacral NCCs contribute a small subset of enteric neurons and glia in the opposite direction (i.e., posterior to anterior), entering the hindgut mesenchyme around e13.5 and then intermingling with the vagal NCC-derived ENS progenitors at e14.5 [40].
Of note, a subset of vagal NCCs also migrate along the mesentery during the e9.5–e14.5 period [41,42,43,44], hence entering the developing gut at multiple sites along the anterior–posterior axis [44]. Multiple points of entry similarly characterize the contribution of subsets of both vagal and trunk NCCs that have adopted a Schwann cell precursor (SCP) intermediate state, and thus colonize the developing gut via extrinsic nerve tracts [45,46]. SCPs of trunk origin appear to be the latest to colonize the developing gut [46], contributing to the ENS only after some of the other ENS progenitors from the myenteric plexus have migrated radially inward to form the submucosal plexus (from e15.5 onwards) [47,48].
Information about potential non-NCC sources of ENS progenitors is scarce. There is one study reporting a contribution from the ventral neural tube in chick embryos [49], while a more recent study reports a contribution from gut/pancreas endodermal epithelium in mouse embryos [50]. In both cases, the contribution to the developing ENS was mentioned to occur slightly after the colonization by vagal NCCs [49,50]. This contribution appeared minor and regionally restricted, either radially for the endoderm source (in the myenteric plexus only) [50] or along the anterior–posterior axis for the ventral neural tube source (in the foregut only) [49]. Moreover, the endoderm source seems further limited in terms of differentiation potential, contributing some enteric neurons but no glia [50].

3. Formation and Diversification of EGCs

The differentiation of ENS progenitors into enteric neurons and glia mostly occurs during gut colonization, before birth. For over 20 years, it has been known that this process is strongly skewed toward a neurogenic fate, as notably evidenced by the significant delay between the appearance of the earliest markers of committed enteric neurons and those of EGCs, reaching ~2 days in the foregut of mouse embryos (e10.0–10.5 vs. e11.5–12.0, respectively) [51,52]. This neurogenic bias suggests that early enteric gliogenesis must first involve countermeasures against the pro-neuronal molecular machinery. Yet, we are still virtually blind about how exactly the neurogenic-to-gliogenic fate transition is molecularly orchestrated in the developing ENS, with very little advancement over the past years [53].
FABP7 (Fatty Acid Binding Protein 7) is generally considered as the earliest marker of committed EGCs [51]. However, this metabolic protein is most likely not playing an active role in the regulation of EGC differentiation, per se. Such a role must instead be imparted to a gene regulatory network involving specific transcription factors and signaling pathways. Efforts to assemble a gene regulatory network for vagal NCCs and their derived ENS progenitors have begun [54], but we are very far from this level of precision in the case of enteric gliogenesis. Indeed, as reviewed a few times over the past years [53,55,56], only a handful of relevant positive regulators are currently known and/or suspected to play a role in enteric gliogenesis (Table 4). Moreover, as again recently evidenced by spatially restricted transcriptome studies [57], many of these pro-glial regulators are also expressed in ENS progenitors (and/or in NCCs/SCPs before they colonize the developing gut), thereby complicating their functional analysis in committed EGCs. In the context of constitutive loss-of-function experiments, this is notably reflected by early defects in ENS progenitors that preclude and/or confound the analysis of enteric gliogenesis. This problem of reiterated roles can in theory be addressed by Cre/LoxP-based conditional loss-of-function approaches, but this possibility remains somehow limited for the same reason; there is currently no Cre driver line with exclusive activity in EGCs and not in ENS progenitors. Alternatively, gain-of-function experiments appear to be a relatively simple way for acquiring information about enteric gliogenesis, as notably demonstrated for the NR2F1 transcription factor [58] and the Hedgehog signaling pathway [59,60].
Hopefully, single-cell transcriptomics-based analyses of the developing mammalian ENS [90,91,92,93] will help to identify new candidate regulators of the neurogenic-to-gliogenic fate transition. These findings should pave the way for future functional investigations, particularly as more comprehensive and glia-focused studies across multiple stages are starting to emerge [94,95]. This will most likely take longer to identify candidate regulators of EGC diversification, notably because we do not yet really know when the different subtypes of EGCs begin to appear. Another difficulty is that EGC diversification can take different forms in mammals (i.e., morphological/topological, functional or transcriptional; see Table 1, Table 2 and Table 3), which are currently hard to reconcile. Perhaps a meta-analysis of all transcriptional subtypes that are listed in Table 3 might be helpful, but the high heterogeneity of experimental conditions that were used to generate these data makes this quite unlikely. Moreover, there is a need to systematically validate these transcriptomic data by immunofluorescence analyses aimed at visualizing the spatiotemporal distribution of the associated proteins. Notably, this would allow to address the question of whether the different topo-morphological EGC subtypes could also be identified with specific markers. A pilot experiment shows that this is not the case for SLC18A2, which has previously allowed to define a transcriptional subtype of EGCs [13] with likely neurogenic potential [30] but that we have found not to be confined to a particular topo-morphological subtype (Figure 2).
Now that we are more aware of the diverse sources of ENS progenitors, we should also consider the possibility that these different origins might contribute to EGC diversification as well. Although clonal analysis of ENS formation in the small intestine suggests that all four topo-morphological subtypes of EGCs can be engendered by a single ENS progenitor [92], this does not mean that all types of ENS progenitors contribute equally in all segments of the gastrointestinal tract. Moreover, it is important not to forget the additional potential contribution of structural and/or environmental changes that occur within the gut wall and/or the lumen during gut morphogenesis (at both prenatal and postnatal stages). A good example is the impact of the microbiota, which was shown to be key for attracting EGCs in the mucosa (topo-morphological EGC Type III(Mucosa)) of mice around weaning age [96]—although this specific mode of regulation is not universal, being notably absent in humans [97].

4. Plasticity and Multipotency of EGCs

4.1. EGCs’ Plasticity

Once generated and integrated in the mature ENS, EGCs are not static. On the contrary, EGCs exhibit a high level of phenotypic plasticity, which we here define by changes in molecular composition, structure and/or function. Under physiological conditions, EGCs’ plasticity is not obvious at first glance, with a single study reporting dynamic GFAP expression in murine topo-morphological Type 1 EGCs [23]. As recently reviewed in more detail elsewhere [20,22], the plasticity of EGCs is instead primarily evidenced under pathological circumstances, such as intestinal inflammation or infection, which trigger reactive gliosis. In addition to transient changes in the expression of glial markers (e.g., GFAP, S100β) [98], reactive EGCs can be characterized by changes in morphology (e.g., increased length and thickness of glial processes) [99], secretion of pro-inflammatory mediators (e.g., IL-1B, IL-6, NO) [100,101,102], immune competence (e.g., T lymphocyte activation via surface expression of MHC-II) [103], proliferative activity [104] or pro-apoptotic potential [105].
Depending on context, these changes are believed to have either detrimental effects by exacerbating pathological inflammatory processes or beneficial effects by neutralizing inflammation and promoting repair [22]. Accordingly, as indicated in Section 5, some of these aspects of reactive enteric gliosis are currently considered potential therapeutic targets for several gastrointestinal diseases. However, optimizing such approaches will require a better understanding of how the different EGC subtypes respond to gliosis triggers. As such responses are likely variable as a function of EGC subtypes, this knowledge might pave the way to more precise interventions restricted to single EGC subtypes.

4.2. EGCs’ Multipotency

In addition to their extensive phenotypic plasticity, a subset of EGCs have the remarkable capacity to self-renew and differentiate into enteric neurons. Current knowledge suggests that this subset of EGCs with stem cell-like properties corresponds to what was initially reported to be a population of postnatal/adult ENS stem cells in mice [106,107,108] and humans [109,110,111]. As outlined in Table 5, the stem cell-like properties of EGCs vary as a function of experimental conditions in mice, being virtually undetectable under steady-state conditions in vivo. Yet, proliferation and neuronal differentiation of adult EGCs do exist during homeostasis in zebrafish [112], suggesting that these properties were somehow attenuated during vertebrate evolution. The stem cell-like properties of mammalian EGCs are nonetheless especially obvious in vitro, where EGCs sorted from adult bowels can not only be differentiated into neurons and glia but also into myofibroblasts [113]—as also noted in the early reports of postnatal/adult ENS stem cells [106,107,108,109]. Whether postnatal EGCs have this capacity to generate myofibroblasts in vivo is currently unknown. If it exists, this differentiation potential will probably require special circumstances to be revealed. Smooth muscle injury would most likely be a prerequisite in this case, just like ENS injury appears required to awake the self-renewing and neurogenic potential of EGCs in mice [114,115,116].
Further research is clearly necessary to fully understand both the nature and the regulatory mechanisms of EGCs’ stem cell-like properties in mammals. One especially important question to address is whether the self-renewal and multipotency of EGCs seen at the population level are combined in a specific EGC subtype or are instead divided in different EGC subtypes. Comparison of thymidine analog incorporation assays and cell lineage tracing studies suggest that neuronal differentiation from EGCs mostly occurs independently of cell proliferation [113,114,116], but both types of analyses will need to be combined to clearly establish the extent of such trans-differentiation capacity. In connection with this, are EGC-derived neurons exclusively made from the neurogenic EGC subtypes recently identified by scRNA-seq [30]? Do each of the two neurogenic EGC subtypes identified in this study generate mutually exclusive neuron subtypes? Similar questions specifically arise for the self-renewal of EGCs. Is it an intrinsic property of all topo-morphological subtypes of EGCs? Responses to all these questions will be required to take full advantage of EGCs’ multipotency for therapeutic purposes.

5. Taking Advantage of EGCs’ Plasticity and Multipotency for Therapeutic Purposes

5.1. Control of Inflammation and Infection in the Gastrointestinal Tract

As mentioned in the previous section, reactive EGCs are involved in the pathogenesis of various gastrointestinal disorders [22]. In the case of IBD (inflammatory bowel diseases, which include ulcerative colitis and Crohn’s disease), reactive EGCs primarily adopt a pro-inflammatory phenotype that exacerbates both innate and adaptative immune responses [21]. Similar observations have also been made in the context of IBS (irritable bowel syndrome) [118,119] and POI (postoperative ileus) [120]. Although there are no specific drugs/products that specifically target EGCs, several studies have nonetheless successfully modulated the detrimental effects of enteric gliosis for therapeutic purposes [22,121]. For example, Pentamidine, a broad-spectrum anti-infective small molecule that targets and inhibits S100β, can prevent 5-Fluorouracil-induced intestinal mucositis and associated enteric neurotoxicity by decreasing S100β secretion from reactive EGCs, thereby attenuating downstream RAGE/NF-κB signaling [122]. Interestingly, not only conventional drugs but also nutraceutical products have shown promising effects in modulating the pathological effects of reactive EGCs [121]. For instance, the cannabinoid-related PEA (palmitoylethanolamide, found in soybeans and peanuts) was reported to exert an anti-inflammatory effect in the context of ulcerative colitis by targeting and activating PPARα which then inhibits S100β production/secretion from reactive EGCs [123]. Of note, PEA also proved useful in the case of HIV-1 Tat-induced diarrhea via the same PPARα-dependent mechanism in reactive EGCs [124].
While most therapeutic strategies in this area focus on mitigating the deleterious effects of reactive EGCs, it should not be forgotten that these cells may also have beneficial effects that might be taken advantage of. One especially appealing possibility would be to control the secretion of GDNF, which was found to be turned on in reactive EGCs in the context of Crohn’s disease [125], and whose beneficial effects on restoring epithelial barrier integrity in this same pathological context are well known [126,127].

5.2. Repair and Regeneration of the ENS

The discovery of postnatal/adult ENS stem cells [106,107,108,109,110,111] has sparked great interest for the development of cell transplantation-based therapies aimed at regenerating the damaged/missing ENS. We now assume that this stem/progenitor cell population is mostly composed of intrinsic EGCs (Table 5), but at least a minor contribution from extrinsic Schwann cells is also likely. Indeed, extrinsic Schwann cells are closely associated with intestinal tissues and are often labeled with the same transgenic markers (driven by Plp1, Nestin or Sox10 regulatory sequences) used to label EGCs, and thus are hard to be excluded from gastrointestinal cell preparations. Moreover, reminiscent of the normal capacity of SCPs to form enteric neurons during late ENS development [46], Schwann cells from adult peripheral nerves can be grown as neurospheres and differentiated into neurons both in culture and when transplanted in the mouse gastrointestinal tract in vivo [128].
Mouse models of Hirschsprung disease have been the preferred tools for testing and developing cell transplantation-based therapies [128,129,130,131,132,133,134], although diseases with less severe phenotypes (e.g., oesophageal achalasia, gastroparesis) are now increasingly recognized as likely being more amenable to therapy in a real-world setting [135]. Hirschsprung disease is characterized by the complete lack of ENS ganglia over varying lengths of the rectum and distal colon, due to incomplete colonization by vagal NCC-derived ENS progenitors [33,136]. Yet, the so-called aganglionic segment is naturally enriched in Schwann cells owing to the overabundance of extrinsic nerves in this context [137]. This has important practical implications for highly desirable autologous cell-based therapies, explaining why not only the ENS-containing region [132], but also the ENS-devoid region [138,139], can be a source of ENS stem/progenitor cells likely enriched in EGCs and Schwann cells, respectively. However, it is currently unclear if both sources can generate the same complement of enteric neuron subtypes after ex vivo expansion and in vivo transplantation. SCP-derived enteric neurons are normally strongly biased towards an excitatory CALR+ phenotype, with only minimal contribution to the inhibitory NOS1+ pool [46]. Although cell culture can reprogram the cell differentiation potential, the extent of derivatives made from EGC- and Schwann cell-derived ENS stem/progenitor cells might nonetheless remain skewed somehow. The same question also applies to the diversity of EGC subtypes that can be engendered from each source of ENS stem/progenitor cells.
One possibility for maximizing neuronal and glial diversification—and, hence, functional recovery of the reconstituted ENS—would be to co-transplant ENS stem/progenitor cells of different origins, as recently experimented for vagal and sacral NCC-derived ENS progenitors differentiated from human pluripotent stem cells [134]. That being said, in situ stimulation of tissue-resident ENS stem/progenitor cells appears as a much simpler approach to address this issue, and GDNF proved to be a potent trigger in this context [140,141]. Indeed, rectal administration of GDNF over a relatively short period of time after birth (five days) induced a new functional ENS in the otherwise aganglionic colon of three genetically distinct mouse models of Hirschsprung disease (Piebald-Lethal [142], Holstein [143] and TashT [144]). This treatment stimulated neurogenesis and gliogenesis in both aganglionic and hypoganglionic segments [140,141], generating several neuronal subtypes in the aganglionic zone while also correcting the cholinergic vs. nitrergic neuronal imbalance normally found in the upstream hypoganglionic zone [141,145]. Intriguingly, genetic cell lineage tracing studies using the Schwann cell-specific Cre driver Dhh-Cre revealed that only about a third of GDNF-induced neurons are derived from this lineage in the aganglionic segment. Moreover, combined EdU incorporation assays showed that the majority of GDNF-induced neurons were not derived from a dividing precursor. Other data suggest that sacral NCC-derived EGCs might also be present in the aganglionic segment [141], but their contribution to the regenerative process, if any, is currently unknown. Like for cell transplantation-based therapies, it also remains to be known if Schwann cell- and EGC-derived ENS stem/progenitor cells generate their own set of neuronal and glial subtypes. Addressing these questions in the context of Hirschsprung disease will also be important for improving our general knowledge of ENS stem/progenitor cells.

6. Conclusions and Perspectives

EGCs are now recognized to be almost as important as enteric neurons in orchestrating several gastrointestinal functions, but we still know very little about how these functions are taken in charge by the different EGC subtypes that were noted recently. As more and more tools and datasets are being generated, the field seems to have entered a new era which should soon yield significant breakthroughs. Increasing our knowledge of EGC formation and function will be important not only for managing numerous gastrointestinal diseases but also potentially for many neurological disorders involving protein aggregates, like Parkinson disease [146,147,148] or amyotrophic lateral sclerosis [149,150,151], which are suspected to start in the ENS before spreading in the brain via extrinsic nerves—either directly (via retrograde transport of protein aggregates) or indirectly (via gut microbiota-derived metabolites) [152]. For example, since reactive EGCs are likely involved during the earliest stages of both Parkinson disease [153,154] and amyotrophic lateral sclerosis [151] like they are in IBD, the development of therapeutic strategies targeting these cells might hence be useful in all of these contexts.

Author Contributions

M.A.L., R.S. and N.P. conceptualized and wrote the manuscript draft. N.P. edited the text. All authors have read and agreed to the published version of the manuscript.

Funding

This study was funded by grants from the Natural Sciences and Engineering Research Council of Canada (NSERC grant # RGPIN-2019-07076) and Canadian Institutes of Health Research (CIHR grant # PJT-180290) to N.P.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

All relevant data are included in the article.

Acknowledgments

The authors thank Baptiste Charrier and other members of the Pilon lab for fruitful discussions about the manuscript, as well as the Fondation Courtois for financially supporting the UQAM Research Chair on Rare Genetic Diseases held by N.P.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Schneider, S.; Wright, C.M.; Heuckeroth, R.O. Unexpected Roles for the Second Brain: Enteric Nervous System as Master Regulator of Bowel Function. Annu. Rev. Physiol. 2019, 81, 235–259. [Google Scholar] [CrossRef]
  2. Furness, J.B. The enteric nervous system and neurogastroenterology. Nat. Rev. Gastroenterol. Hepatol. 2012, 9, 286–294. [Google Scholar] [CrossRef] [PubMed]
  3. Sharkey, K.A.; Mawe, G.M. The enteric nervous system. Physiol. Rev. 2023, 103, 1487–1564. [Google Scholar] [CrossRef] [PubMed]
  4. Foong, J.P.P.; Hung, L.Y.; Poon, S.; Savidge, T.C.; Bornstein, J.C. Early life interaction between the microbiota and the enteric nervous system. Am. J. Physiol. Gastrointest. Liver Physiol. 2020, 319, G541–G548. [Google Scholar] [CrossRef]
  5. Obata, Y.; Castano, A.; Boeing, S.; Bon-Frauches, A.C.; Fung, C.; Fallesen, T.; de Aguero, M.G.; Yilmaz, B.; Lopes, R.; Huseynova, A.; et al. Neuronal programming by microbiota regulates intestinal physiology. Nature 2020, 578, 284–289. [Google Scholar] [CrossRef] [PubMed]
  6. Obata, Y.; Pachnis, V. The Effect of Microbiota and the Immune System on the Development and Organization of the Enteric Nervous System. Gastroenterology 2016, 151, 836–844. [Google Scholar] [CrossRef] [Green Version]
  7. Toure, A.M.; Landry, M.; Souchkova, O.; Kembel, S.W.; Pilon, N. Gut microbiota-mediated Gene-Environment interaction in the TashT mouse model of Hirschsprung disease. Sci. Rep. 2019, 9, 492. [Google Scholar] [CrossRef] [Green Version]
  8. Yoo, B.B.; Mazmanian, S.K. The Enteric Network: Interactions between the Immune and Nervous Systems of the Gut. Immunity 2017, 46, 910–926. [Google Scholar] [CrossRef] [Green Version]
  9. Progatzky, F.; Pachnis, V. The role of enteric glia in intestinal immunity. Curr. Opin. Immunol. 2022, 77, 102183. [Google Scholar] [CrossRef]
  10. Rao, M.; Gershon, M.D. The bowel and beyond: The enteric nervous system in neurological disorders. Nat. Rev. Gastroenterol. Hepatol. 2016, 13, 517–528. [Google Scholar] [CrossRef] [Green Version]
  11. Uesaka, T.; Young, H.M.; Pachnis, V.; Enomoto, H. Development of the intrinsic and extrinsic innervation of the gut. Dev. Biol. 2016, 417, 158–167. [Google Scholar] [CrossRef] [PubMed]
  12. May-Zhang, A.A.; Tycksen, E.; Southard-Smith, A.N.; Deal, K.K.; Benthal, J.T.; Buehler, D.P.; Adam, M.; Simmons, A.J.; Monaghan, J.R.; Matlock, B.K.; et al. Combinatorial Transcriptional Profiling of Mouse and Human Enteric Neurons Identifies Shared and Disparate Subtypes In Situ. Gastroenterology 2020, 160, 755–770. [Google Scholar] [CrossRef] [PubMed]
  13. Drokhlyansky, E.; Smillie, C.S.; Van Wittenberghe, N.; Ericsson, M.; Griffin, G.K.; Eraslan, G.; Dionne, D.; Cuoco, M.S.; Goder-Reiser, M.N.; Sharova, T.; et al. The Human and Mouse Enteric Nervous System at Single-Cell Resolution. Cell 2020, 182, 1606–1622.e23. [Google Scholar] [CrossRef] [PubMed]
  14. Chen, B.N.; Humenick, A.; Yew, W.P.; Peterson, R.A.; Wiklendt, L.; Dinning, P.G.; Spencer, N.J.; Wattchow, D.A.; Costa, M.; Brookes, S.J.H. Types of Neurons in the Human Colonic Myenteric Plexus Identified by Multilayer Immunohistochemical Coding. Cell. Mol. Gastroenterol. Hepatol. 2023. [Google Scholar] [CrossRef] [PubMed]
  15. Grubisic, V.; Gulbransen, B.D. Enteric glia: The most alimentary of all glia. J. Physiol. 2016, 595, 557–570. [Google Scholar] [CrossRef] [Green Version]
  16. Neunlist, M.; Rolli-Derkinderen, M.; Latorre, R.; Van Landeghem, L.; Coron, E.; Derkinderen, P.; De Giorgio, R. Enteric glial cells: Recent developments and future directions. Gastroenterology 2014, 147, 1230–1237. [Google Scholar] [CrossRef] [PubMed]
  17. Sharkey, K.A. Emerging roles for enteric glia in gastrointestinal disorders. J. Clin. Investig. 2015, 125, 918–925. [Google Scholar] [CrossRef]
  18. Progatzky, F.; Shapiro, M.; Chng, S.H.; Garcia-Cassani, B.; Classon, C.H.; Sevgi, S.; Laddach, A.; Bon-Frauches, A.C.; Lasrado, R.; Rahim, M.; et al. Regulation of intestinal immunity and tissue repair by enteric glia. Nature 2021, 599, 125–130. [Google Scholar] [CrossRef]
  19. Baghdadi, M.B.; Ayyaz, A.; Coquenlorge, S.; Chu, B.; Kumar, S.; Streutker, C.; Wrana, J.L.; Kim, T.H. Enteric glial cell heterogeneity regulates intestinal stem cell niches. Cell Stem Cell 2022, 29, 86–100.e6. [Google Scholar] [CrossRef]
  20. Baghdadi, M.B.; Kim, T.H. The multiple roles of enteric glial cells in intestinal homeostasis and regeneration. Semin. Cell Dev. Biol. 2023, 150–151, 43–49. [Google Scholar] [CrossRef]
  21. Liu, C.; Yang, J. Enteric Glial Cells in Immunological Disorders of the Gut. Front. Cell. Neurosci. 2022, 16, 895871. [Google Scholar] [CrossRef] [PubMed]
  22. Seguella, L.; Gulbransen, B.D. Enteric glial biology, intercellular signalling and roles in gastrointestinal disease. Nat. Rev. Gastroenterol. Hepatol. 2021, 18, 571–587. [Google Scholar] [CrossRef] [PubMed]
  23. Boesmans, W.; Lasrado, R.; Vanden Berghe, P.; Pachnis, V. Heterogeneity and phenotypic plasticity of glial cells in the mammalian enteric nervous system. Glia 2015, 63, 229–241. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  24. Gulbransen, B.D.; Sharkey, K.A. Novel functional roles for enteric glia in the gastrointestinal tract. Nat. Rev. Gastroenterol. Hepatol. 2012, 9, 625–632. [Google Scholar] [CrossRef] [PubMed]
  25. Seguella, L.; McClain, J.L.; Esposito, G.; Gulbransen, B.D. Functional Intraregional and Interregional Heterogeneity between Myenteric Glial Cells of the Colon and Duodenum in Mice. J. Neurosci. 2022, 42, 8694–8708. [Google Scholar] [CrossRef] [PubMed]
  26. Zeisel, A.; Hochgerner, H.; Lonnerberg, P.; Johnsson, A.; Memic, F.; van der Zwan, J.; Haring, M.; Braun, E.; Borm, L.E.; La Manno, G.; et al. Molecular Architecture of the Mouse Nervous System. Cell 2018, 174, 999–1014.e22. [Google Scholar] [CrossRef] [Green Version]
  27. Wright, C.M.; Schneider, S.; Smith-Edwards, K.M.; Mafra, F.; Leembruggen, A.J.L.; Gonzalez, M.V.; Kothakapa, D.R.; Anderson, J.B.; Maguire, B.A.; Gao, T.; et al. scRNA-Seq Reveals New Enteric Nervous System Roles for GDNF, NRTN, and TBX3. Cell. Mol. Gastroenterol. Hepatol. 2021, 11, 1548–1592.e1. [Google Scholar] [CrossRef]
  28. Roulis, M.; Kaklamanos, A.; Schernthanner, M.; Bielecki, P.; Zhao, J.; Kaffe, E.; Frommelt, L.S.; Qu, R.; Knapp, M.S.; Henriques, A.; et al. Paracrine orchestration of intestinal tumorigenesis by a mesenchymal niche. Nature 2020, 580, 524–529. [Google Scholar] [CrossRef] [PubMed]
  29. Kinchen, J.; Chen, H.H.; Parikh, K.; Antanaviciute, A.; Jagielowicz, M.; Fawkner-Corbett, D.; Ashley, N.; Cubitt, L.; Mellado-Gomez, E.; Attar, M.; et al. Structural Remodeling of the Human Colonic Mesenchyme in Inflammatory Bowel Disease. Cell 2018, 175, 372–386.e17. [Google Scholar] [CrossRef] [Green Version]
  30. Guyer, R.A.; Stavely, R.; Robertson, K.; Bhave, S.; Mueller, J.L.; Picard, N.M.; Hotta, R.; Kaltschmidt, J.A.; Goldstein, A.M. Single-cell multiome sequencing clarifies enteric glial diversity and identifies an intraganglionic population poised for neurogenesis. Cell Rep. 2023, 42, 112194. [Google Scholar] [CrossRef]
  31. Schneider, S.K.; Pauli, P.; Lautenbacher, S.; Reicherts, P. Effects of psychosocial stress and performance feedback on pain processing and its correlation with subjective and neuroendocrine parameters. Scand. J. Pain 2023, 23, 389–401. [Google Scholar] [CrossRef] [PubMed]
  32. Soldatov, R.; Kaucka, M.; Kastriti, M.E.; Petersen, J.; Chontorotzea, T.; Englmaier, L.; Akkuratova, N.; Yang, Y.; Häring, M.; Dyachuk, V.; et al. Spatiotemporal structure of cell fate decisions in murine neural crest. Science 2019, 364, eaas9536. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  33. Pilon, N. Treatment and Prevention of Neurocristopathies. Trends Mol. Med. 2021, 27, 451–468. [Google Scholar] [CrossRef]
  34. Yntema, C.L.; Hammond, W.S. The origin of intrinsic ganglia of trunk viscera from vagal neural crest in the chick embryo. J. Comp. Neurol. 1954, 101, 515–541. [Google Scholar] [CrossRef] [PubMed]
  35. Durbec, P.L.; Larsson-Blomberg, L.B.; Schuchardt, A.; Costantini, F.; Pachnis, V. Common origin and developmental dependence on c-ret of subsets of enteric and sympathetic neuroblasts. Development 1996, 122, 349–358. [Google Scholar] [CrossRef]
  36. Green, S.A.; Uy, B.R.; Bronner, M.E. Ancient evolutionary origin of vertebrate enteric neurons from trunk-derived neural crest. Nature 2017, 544, 88–91. [Google Scholar] [CrossRef] [Green Version]
  37. Burns, A.J.; Le Douarin, N.M. The sacral neural crest contributes neurons and glia to the post-umbilical gut: Spatiotemporal analysis of the development of the enteric nervous system. Development 1998, 125, 4335–4347. [Google Scholar] [CrossRef]
  38. Le Douarin, N.M.; Teillet, M.A. The migration of neural crest cells to the wall of the digestive tract in avian embryo. J. Embryol. Exp. Morphol. 1973, 30, 31–48. [Google Scholar] [CrossRef]
  39. Kapur, R.P.; Yost, C.; Palmiter, R.D. A transgenic model for studying development of the enteric nervous system in normal and aganglionic mice. Development 1992, 116, 167–175. [Google Scholar] [CrossRef]
  40. Wang, X.; Chan, A.K.K.; Sham, M.H.; Burns, A.J.; Chan, W.Y. Analysis of the Sacral Neural Crest Cell Contribution to the Hindgut Enteric Nervous System in the Mouse Embryo. Gastroenterology 2011, 141, 992–1002.e6. [Google Scholar] [CrossRef] [Green Version]
  41. Coventry, S.; Yost, C.; Palmiter, R.D.; Kapur, R.P. Migration of ganglion cell precursors in the ileoceca of normal and lethal spotted embryos, a murine model for Hirschsprung disease. Lab. Investig. 1994, 71, 82–93. [Google Scholar] [PubMed]
  42. Druckenbrod, N.R.; Epstein, M.L. The pattern of neural crest advance in the cecum and colon. Dev. Biol. 2005, 287, 125–133. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  43. Nishiyama, C.; Uesaka, T.; Manabe, T.; Yonekura, Y.; Nagasawa, T.; Newgreen, D.F.; Young, H.M.; Enomoto, H. Trans-mesenteric neural crest cells are the principal source of the colonic enteric nervous system. Nat. Neurosci. 2012, 15, 1211–1218. [Google Scholar] [CrossRef] [PubMed]
  44. Yu, Q.; Du, M.; Zhang, W.; Liu, L.; Gao, Z.; Chen, W.; Gu, Y.; Zhu, K.; Niu, X.; Sun, Q.; et al. Mesenteric Neural Crest Cells Are the Embryological Basis of Skip Segment Hirschsprung’s Disease. Cell. Mol. Gastroenterol. Hepatol. 2021, 12, 1–24. [Google Scholar] [CrossRef]
  45. Espinosa-Medina, I.; Jevans, B.; Boismoreau, F.; Chettouh, Z.; Enomoto, H.; Muller, T.; Birchmeier, C.; Burns, A.J.; Brunet, J.F. Dual origin of enteric neurons in vagal Schwann cell precursors and the sympathetic neural crest. Proc. Natl. Acad. Sci. USA 2017, 114, 11980–11985. [Google Scholar] [CrossRef] [Green Version]
  46. Uesaka, T.; Nagashimada, M.; Enomoto, H. Neuronal Differentiation in Schwann Cell Lineage Underlies Postnatal Neurogenesis in the Enteric Nervous System. J. Neurosci. 2015, 35, 9879–9888. [Google Scholar] [CrossRef] [Green Version]
  47. McKeown, S.J.; Chow, C.W.; Young, H.M. Development of the submucous plexus in the large intestine of the mouse. Cell Tissue Res. 2001, 303, 301–305. [Google Scholar] [CrossRef]
  48. Uesaka, T.; Nagashimada, M.; Enomoto, H. GDNF signaling levels control migration and neuronal differentiation of enteric ganglion precursors. J. Neurosci. 2013, 33, 16372–16382. [Google Scholar] [CrossRef] [Green Version]
  49. Sohal, G.S.; Ali, M.M.; Farooqui, F.A. A second source of precursor cells for the developing enteric nervous system and interstitial cells of Cajal. Int. J. Dev. Neurosci. 2002, 20, 619–626. [Google Scholar] [CrossRef]
  50. Brokhman, I.; Xu, J.; Coles, B.L.K.; Razavi, R.; Engert, S.; Lickert, H.; Babona-Pilipos, R.; Morshead, C.M.; Sibley, E.; Chen, C.; et al. Dual embryonic origin of the mammalian enteric nervous system. Dev. Biol. 2019, 445, 256–270. [Google Scholar] [CrossRef]
  51. Young, H.M.; Bergner, A.J.; Muller, T. Acquisition of neuronal and glial markers by neural crest-derived cells in the mouse intestine. J. Comp. Neurol. 2003, 456, 1–11. [Google Scholar] [CrossRef] [PubMed]
  52. Young, H.M.; Ciampoli, D.; Hsuan, J.; Canty, A.J. Expression of Ret-, p75(NTR)-, Phox2a-, Phox2b-, and tyrosine hydroxylase-immunoreactivity by undifferentiated neural crest-derived cells and different classes of enteric neurons in the embryonic mouse gut. Dev. Dyn. 1999, 216, 137–152. [Google Scholar] [CrossRef]
  53. Charrier, B.; Pilon, N. Toward a better understanding of enteric gliogenesis. Neurogenesis 2017, 4, e1293958. [Google Scholar] [CrossRef] [Green Version]
  54. Ling, I.T.C.; Sauka-Spengler, T. Early chromatin shaping predetermines multipotent vagal neural crest into neural, neuronal and mesenchymal lineages. Nat. Cell Biol. 2019, 21, 1504–1517. [Google Scholar] [CrossRef]
  55. Boesmans, W.; Nash, A.; Tasnady, K.R.; Yang, W.; Stamp, L.A.; Hao, M.M. Development, Diversity, and Neurogenic Capacity of Enteric Glia. Front. Cell Dev. Biol. 2021, 9, 775102. [Google Scholar] [CrossRef] [PubMed]
  56. Rosenberg, H.J.; Rao, M. Enteric glia in homeostasis and disease: From fundamental biology to human pathology. iScience 2021, 24, 102863. [Google Scholar] [CrossRef]
  57. Stavely, R.; Hotta, R.; Guyer, R.A.; Picard, N.; Rahman, A.A.; Omer, M.; Soos, A.; Szocs, E.; Mueller, J.; Goldstein, A.M.; et al. A distinct transcriptome characterizes neural crest-derived cells at the migratory wavefront during enteric nervous system development. Development 2023, 150, dev201090. [Google Scholar] [CrossRef] [PubMed]
  58. Bergeron, K.F.; Nguyen, C.M.; Cardinal, T.; Charrier, B.; Silversides, D.W.; Pilon, N. Upregulation of the Nr2f1-A830082K12Rik gene pair in murine neural crest cells results in a complex phenotype reminiscent of waardenburg syndrome type 4. Dis. Models Mech. 2016, 9, 1283–1293. [Google Scholar] [CrossRef] [Green Version]
  59. Liu, J.A.; Lai, F.P.; Gui, H.S.; Sham, M.H.; Tam, P.K.; Garcia-Barcelo, M.M.; Hui, C.C.; Ngan, E.S. Identification of GLI Mutations in Patients With Hirschsprung Disease That Disrupt Enteric Nervous System Development in Mice. Gastroenterology 2015, 149, 1837–1848.e5. [Google Scholar] [CrossRef]
  60. Ngan, E.S.; Garcia-Barcelo, M.M.; Yip, B.H.; Poon, H.C.; Lau, S.T.; Kwok, C.K.; Sat, E.; Sham, M.H.; Wong, K.K.; Wainwright, B.J.; et al. Hedgehog/Notch-induced premature gliogenesis represents a new disease mechanism for Hirschsprung disease in mice and humans. J. Clin. Investig. 2011, 121, 3467–3478. [Google Scholar] [CrossRef] [Green Version]
  61. Lo, L.C.; Johnson, J.E.; Wuenschell, C.W.; Saito, T.; Anderson, D.J. Mammalian achaete-scute homolog 1 is transiently expressed by spatially restricted subsets of early neuroepithelial and neural crest cells. Genes Dev. 1991, 5, 1524–1537. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  62. Memic, F.; Knoflach, V.; Sadler, R.; Tegerstedt, G.; Sundstrom, E.; Guillemot, F.; Pachnis, V.; Marklund, U. Ascl1 Is Required for the Development of Specific Neuronal Subtypes in the Enteric Nervous System. J. Neurosci. 2016, 36, 4339–4350. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  63. Okamura, Y.; Saga, Y. Notch signaling is required for the maintenance of enteric neural crest progenitors. Development 2008, 135, 3555–3565. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  64. Labosky, P.A.; Kaestner, K.H. The winged helix transcription factor Hfh2 is expressed in neural crest and spinal cord during mouse development. Mech. Dev. 1998, 76, 185–190. [Google Scholar] [CrossRef]
  65. Dottori, M.; Gross, M.K.; Labosky, P.; Goulding, M. The winged-helix transcription factor Foxd3 suppresses interneuron differentiation and promotes neural crest cell fate. Development 2001, 128, 4127–4138. [Google Scholar] [CrossRef]
  66. Teng, L.; Mundell, N.A.; Frist, A.Y.; Wang, Q.; Labosky, P.A. Requirement for Foxd3 in the maintenance of neural crest progenitors. Development 2008, 135, 1615–1624. [Google Scholar] [CrossRef] [Green Version]
  67. Mundell, N.A.; Plank, J.L.; LeGrone, A.W.; Frist, A.Y.; Zhu, L.; Shin, M.K.; Southard-Smith, E.M.; Labosky, P.A. Enteric nervous system specific deletion of Foxd3 disrupts glial cell differentiation and activates compensatory enteric progenitors. Dev. Biol. 2012, 363, 373–387. [Google Scholar] [CrossRef] [Green Version]
  68. Rada-Iglesias, A.; Bajpai, R.; Prescott, S.; Brugmann, S.A.; Swigut, T.; Wysocka, J. Epigenomic annotation of enhancers predicts transcriptional regulators of human neural crest. Cell Stem Cell 2012, 11, 633–648. [Google Scholar] [CrossRef] [Green Version]
  69. Bonnamour, G.; Charrier, B.; Sallis, S.; Leduc, E.; Pilon, N. NR2F1 regulates a Schwann cell precursor-vs-melanocyte cell fate switch in a mouse model of Waardenburg syndrome type IV. Pigment. Cell Melanoma Res. 2022, 35, 506–516. [Google Scholar] [CrossRef]
  70. Southard-Smith, E.M.; Kos, L.; Pavan, W.J. Sox10 mutation disrupts neural crest development in Dom Hirschsprung mouse model. Nat. Genet. 1998, 18, 60–64. [Google Scholar] [CrossRef] [Green Version]
  71. Kuhlbrodt, K.; Herbarth, B.; Sock, E.; Hermans-Borgmeyer, I.; Wegner, M. Sox10, a novel transcriptional modulator in glial cells. J. Neurosci. 1998, 18, 237–250. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  72. Paratore, C.; Eichenberger, C.; Suter, U.; Sommer, L. Sox10 haploinsufficiency affects maintenance of progenitor cells in a mouse model of Hirschsprung disease. Hum. Mol. Genet. 2002, 11, 3075–3085. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  73. De Bono, C.; Liu, Y.; Ferrena, A.; Valentine, A.; Zheng, D.; Morrow, B.E. Single-cell transcriptomics uncovers a non-autonomous Tbx1-dependent genetic program controlling cardiac neural crest cell development. Nat. Commun. 2023, 14, 1551. [Google Scholar] [CrossRef]
  74. Lopez, S.H.; Avetisyan, M.; Wright, C.M.; Mesbah, K.; Kelly, R.G.; Moon, A.M.; Heuckeroth, R.O. Loss of Tbx3 in murine neural crest reduces enteric glia and causes cleft palate, but does not influence heart development or bowel transit. Dev. Biol. 2018, 444 (Suppl. S1), S337–S351. [Google Scholar] [CrossRef]
  75. Morarach, K.; Mikhailova, A.; Knoflach, V.; Memic, F.; Kumar, R.; Li, W.; Ernfors, P.; Marklund, U. Diversification of molecularly defined myenteric neuron classes revealed by single-cell RNA sequencing. Nat. Neurosci. 2021, 24, 34–46. [Google Scholar] [CrossRef] [PubMed]
  76. Jeong, J.; Mao, J.; Tenzen, T.; Kottmann, A.H.; McMahon, A.P. Hedgehog signaling in the neural crest cells regulates the patterning and growth of facial primordia. Genes Dev. 2004, 18, 937–951. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  77. Fu, M.; Lui, V.C.; Sham, M.H.; Pachnis, V.; Tam, P.K. Sonic hedgehog regulates the proliferation, differentiation, and migration of enteric neural crest cells in gut. J. Cell Biol. 2004, 166, 673–684. [Google Scholar] [CrossRef]
  78. Bitgood, M.J.; McMahon, A.P. Hedgehog and Bmp genes are coexpressed at many diverse sites of cell-cell interaction in the mouse embryo. Dev. Biol. 1995, 172, 126–138. [Google Scholar] [CrossRef] [Green Version]
  79. Echelard, Y.; Epstein, D.J.; St-Jacques, B.; Shen, L.; Mohler, J.; McMahon, J.A.; McMahon, A.P. Sonic hedgehog, a member of a family of putative signaling molecules, is implicated in the regulation of CNS polarity. Cell 1993, 75, 1417–1430. [Google Scholar] [CrossRef]
  80. Nishino, J.; Saunders, T.L.; Sagane, K.; Morrison, S.J. Lgi4 promotes the proliferation and differentiation of glial lineage cells throughout the developing peripheral nervous system. J. Neurosci. 2010, 30, 15228–15240. [Google Scholar] [CrossRef] [Green Version]
  81. Williams, R.; Lendahl, U.; Lardelli, M. Complementary and combinatorial patterns of Notch gene family expression during early mouse development. Mech. Dev. 1995, 53, 357–368. [Google Scholar] [CrossRef] [PubMed]
  82. Mead, T.J.; Yutzey, K.E. Notch pathway regulation of neural crest cell development in vivo. Dev. Dyn. 2012, 241, 376–389. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  83. Woodhoo, A.; Alonso, M.B.; Droggiti, A.; Turmaine, M.; D’Antonio, M.; Parkinson, D.B.; Wilton, D.K.; Al-Shawi, R.; Simons, P.; Shen, J.; et al. Notch controls embryonic Schwann cell differentiation, postnatal myelination and adult plasticity. Nat. Neurosci. 2009, 12, 839–847. [Google Scholar] [CrossRef] [Green Version]
  84. Taylor, M.K.; Yeager, K.; Morrison, S.J. Physiological Notch signaling promotes gliogenesis in the developing peripheral and central nervous systems. Development 2007, 134, 2435–2447. [Google Scholar] [CrossRef] [Green Version]
  85. Britsch, S.; Li, L.; Kirchhoff, S.; Theuring, F.; Brinkmann, V.; Birchmeier, C.; Riethmacher, D. The ErbB2 and ErbB3 receptors and their ligand, neuregulin-1, are essential for development of the sympathetic nervous system. Genes Dev. 1998, 12, 1825–1836. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  86. Meyer, D.; Birchmeier, C. Multiple essential functions of neuregulin in development. Nature 1995, 378, 386–390. [Google Scholar] [CrossRef]
  87. Chalazonitis, A.; D’Autreaux, F.; Pham, T.D.; Kessler, J.A.; Gershon, M.D. Bone morphogenetic proteins regulate enteric gliogenesis by modulating ErbB3 signaling. Dev. Biol. 2011, 350, 64–79. [Google Scholar] [CrossRef] [Green Version]
  88. Jarde, T.; Chan, W.H.; Rossello, F.J.; Kaur Kahlon, T.; Theocharous, M.; Kurian Arackal, T.; Flores, T.; Giraud, M.; Richards, E.; Chan, E.; et al. Mesenchymal Niche-Derived Neuregulin-1 Drives Intestinal Stem Cell Proliferation and Regeneration of Damaged Epithelium. Cell Stem Cell 2020, 27, 646–662.e7. [Google Scholar] [CrossRef]
  89. Riethmacher, D.; Sonnenberg-Riethmacher, E.; Brinkmann, V.; Yamaai, T.; Lewin, G.R.; Birchmeier, C. Severe neuropathies in mice with targeted mutations in the ErbB3 receptor. Nature 1997, 389, 725–730. [Google Scholar] [CrossRef]
  90. Elmentaite, R.; Kumasaka, N.; Roberts, K.; Fleming, A.; Dann, E.; King, H.W.; Kleshchevnikov, V.; Dabrowska, M.; Pritchard, S.; Bolt, L.; et al. Cells of the human intestinal tract mapped across space and time. Nature 2021, 597, 250–255. [Google Scholar] [CrossRef]
  91. Fawkner-Corbett, D.; Antanaviciute, A.; Parikh, K.; Jagielowicz, M.; Geros, A.S.; Gupta, T.; Ashley, N.; Khamis, D.; Fowler, D.; Morrissey, E.; et al. Spatiotemporal analysis of human intestinal development at single-cell resolution. Cell 2021, 184, 810–826.e23. [Google Scholar] [CrossRef]
  92. Lasrado, R.; Boesmans, W.; Kleinjung, J.; Pin, C.; Bell, D.; Bhaw, L.; McCallum, S.; Zong, H.; Luo, L.; Clevers, H.; et al. Lineage-dependent spatial and functional organization of the mammalian enteric nervous system. Science 2017, 356, 722–726. [Google Scholar] [CrossRef]
  93. Majd, H.; Samuel, R.M.; Ramirez, J.T.; Kalantari, A.; Barber, K.; Ghazizadeh, Z.; Chemel, A.K.; Cesiulis, A.; Richter, M.N.; Das, S.; et al. hPSC-Derived Enteric Ganglioids Model Human ENS Development and Function. BioRxiv 2022. [Google Scholar] [CrossRef]
  94. Laddach, A.; Chng, S.H.; Lasrado, R.; Progatzky, F.; Shapiro, M.; Artemov, A.V.; Sampedro Cataneda, M.; Erickson, A.; Bon-Frauches, A.C.; Kleinjung, J.; et al. A branching model of cell fate decisions in the enteric nervous system. BioRxiv 2022. [Google Scholar] [CrossRef]
  95. Scantlen, M.D.; Majd, H.; Fattahi, F. Modeling enteric glia development, physiology and disease using human pluripotent stem cells. Neurosci. Lett. 2023, 811, 137334. [Google Scholar] [CrossRef] [PubMed]
  96. Kabouridis, P.S.; Lasrado, R.; McCallum, S.; Chng, S.H.; Snippert, H.J.; Clevers, H.; Pettersson, S.; Pachnis, V. Microbiota controls the homeostasis of glial cells in the gut lamina propria. Neuron 2015, 85, 289–295. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  97. Inlender, T.; Nissim-Eliraz, E.; Stavely, R.; Hotta, R.; Goldstein, A.M.; Yagel, S.; Gutnick, M.J.; Shpigel, N.Y. Homeostasis of mucosal glial cells in human gut is independent of microbiota. Sci. Rep. 2021, 11, 12796. [Google Scholar] [CrossRef]
  98. Le Berre, C.; Naveilhan, P.; Rolli-Derkinderen, M. Enteric glia at center stage of inflammatory bowel disease. Neurosci. Lett. 2023, 809, 137315. [Google Scholar] [CrossRef]
  99. Delvalle, N.M.; Dharshika, C.; Morales-Soto, W.; Fried, D.E.; Gaudette, L.; Gulbransen, B.D. Communication Between Enteric Neurons, Glia, and Nociceptors Underlies the Effects of Tachykinins on Neuroinflammation. Cell. Mol. Gastroenterol. Hepatol. 2018, 6, 321–344. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  100. Cirillo, C.; Sarnelli, G.; Turco, F.; Mango, A.; Grosso, M.; Aprea, G.; Masone, S.; Cuomo, R. Proinflammatory stimuli activates human-derived enteroglial cells and induces autocrine nitric oxide production. Neurogastroenterol. Motil. 2011, 23, e372–e382. [Google Scholar] [CrossRef]
  101. Murakami, M.; Ohta, T.; Ito, S. Lipopolysaccharides enhance the action of bradykinin in enteric neurons via secretion of interleukin-1beta from enteric glial cells. J. Neurosci. Res. 2009, 87, 2095–2104. [Google Scholar] [CrossRef] [PubMed]
  102. Ruhl, A.; Franzke, S.; Collins, S.M.; Stremmel, W. Interleukin-6 expression and regulation in rat enteric glial cells. Am. J. Physiol. Gastrointest. Liver Physiol. 2001, 280, G1163–G1171. [Google Scholar] [CrossRef] [Green Version]
  103. Chow, A.K.; Grubisic, V.; Gulbransen, B.D. Enteric Glia Regulate Lymphocyte Activation via Autophagy-Mediated MHC-II Expression. Cell. Mol. Gastroenterol. Hepatol. 2021, 12, 1215–1237. [Google Scholar] [CrossRef] [PubMed]
  104. Rühl, A.; Franzke, S.; Stremmel, W. IL-1beta and IL-10 have dual effects on enteric glial cell proliferation. Neurogastroenterol. Motil. 2001, 13, 89–94. [Google Scholar] [CrossRef] [PubMed]
  105. Brown, I.A.M.; McClain, J.L.; Watson, R.E.; Patel, B.A.; Gulbransen, B.D. Enteric Glia Mediate Neuron Death in Colitis Through Purinergic Pathways That Require Connexin-43 and Nitric Oxide. Cell. Mol. Gastroenterol. Hepatol. 2016, 2, 77–91. [Google Scholar] [CrossRef] [Green Version]
  106. Bondurand, N.; Natarajan, D.; Thapar, N.; Atkins, C.; Pachnis, V. Neuron and glia generating progenitors of the mammalian enteric nervous system isolated from foetal and postnatal gut cultures. Development 2003, 130, 6387–6400. [Google Scholar] [CrossRef] [Green Version]
  107. Kruger, G.M.; Mosher, J.T.; Bixby, S.; Joseph, N.; Iwashita, T.; Morrison, S.J. Neural crest stem cells persist in the adult gut but undergo changes in self-renewal, neuronal subtype potential, and factor responsiveness. Neuron 2002, 35, 657–669. [Google Scholar] [CrossRef] [Green Version]
  108. Suarez-Rodriguez, R.; Belkind-Gerson, J. Cultured nestin-positive cells from postnatal mouse small bowel differentiate ex vivo into neurons, glia, and smooth muscle. Stem Cells 2004, 22, 1373–1385. [Google Scholar] [CrossRef]
  109. Metzger, M.; Bareiss, P.M.; Danker, T.; Wagner, S.; Hennenlotter, J.; Guenther, E.; Obermayr, F.; Stenzl, A.; Koenigsrainer, A.; Skutella, T.; et al. Expansion and differentiation of neural progenitors derived from the human adult enteric nervous system. Gastroenterology 2009, 137, 2063–2073.e4. [Google Scholar] [CrossRef]
  110. Metzger, M.; Caldwell, C.; Barlow, A.J.; Burns, A.J.; Thapar, N. Enteric nervous system stem cells derived from human gut mucosa for the treatment of aganglionic gut disorders. Gastroenterology 2009, 136, 2214–2225.e3. [Google Scholar] [CrossRef]
  111. Rauch, U.; Hansgen, A.; Hagl, C.; Holland-Cunz, S.; Schafer, K.H. Isolation and cultivation of neuronal precursor cells from the developing human enteric nervous system as a tool for cell therapy in dysganglionosis. Int. J. Colorectal. Dis. 2006, 21, 554–559. [Google Scholar] [CrossRef]
  112. McCallum, S.; Obata, Y.; Fourli, E.; Boeing, S.; Peddie, C.J.; Xu, Q.; Horswell, S.; Kelsh, R.N.; Collinson, L.; Wilkinson, D.; et al. Enteric glia as a source of neural progenitors in adult zebrafish. Elife 2020, 9, e56086. [Google Scholar] [CrossRef] [PubMed]
  113. Joseph, N.M.; He, S.; Quintana, E.; Kim, Y.G.; Nunez, G.; Morrison, S.J. Enteric glia are multipotent in culture but primarily form glia in the adult rodent gut. J. Clin. Investig. 2011, 121, 3398–3411. [Google Scholar] [CrossRef] [PubMed]
  114. Belkind-Gerson, J.; Graham, H.K.; Reynolds, J.; Hotta, R.; Nagy, N.; Cheng, L.; Kamionek, M.; Shi, H.N.; Aherne, C.M.; Goldstein, A.M. Colitis promotes neuronal differentiation of Sox2+ and PLP1+ enteric cells. Sci. Rep. 2017, 7, 2525. [Google Scholar] [CrossRef] [Green Version]
  115. Belkind-Gerson, J.; Hotta, R.; Nagy, N.; Thomas, A.R.; Graham, H.; Cheng, L.; Solorzano, J.; Nguyen, D.; Kamionek, M.; Dietrich, J.; et al. Colitis induces enteric neurogenesis through a 5-HT4-dependent mechanism. Inflamm. Bowel Dis. 2015, 21, 870–878. [Google Scholar] [CrossRef] [PubMed]
  116. Laranjeira, C.; Sandgren, K.; Kessaris, N.; Richardson, W.; Potocnik, A.; Vanden Berghe, P.; Pachnis, V. Glial cells in the mouse enteric nervous system can undergo neurogenesis in response to injury. J. Clin. Investig. 2011, 121, 3412–3424. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  117. Belkind-Gerson, J.; Carreon-Rodriguez, A.; Benedict, L.A.; Steiger, C.; Pieretti, A.; Nagy, N.; Dietrich, J.; Goldstein, A.M. Nestin-expressing cells in the gut give rise to enteric neurons and glial cells. Neurogastroenterol. Motil. 2013, 25, 61–69.e7. [Google Scholar] [CrossRef] [Green Version]
  118. Lilli, N.L.; Queneherve, L.; Haddara, S.; Brochard, C.; Aubert, P.; Rolli-Derkinderen, M.; Durand, T.; Naveilhan, P.; Hardouin, J.B.; De Giorgio, R.; et al. Glioplasticity in irritable bowel syndrome. Neurogastroenterol. Motil. 2018, 30, e13232. [Google Scholar] [CrossRef]
  119. Meira de-Faria, F.; Casado-Bedmar, M.; Marten Lindqvist, C.; Jones, M.P.; Walter, S.A.; Keita, A.V. Altered interaction between enteric glial cells and mast cells in the colon of women with irritable bowel syndrome. Neurogastroenterol. Motil. 2021, 33, e14130. [Google Scholar] [CrossRef]
  120. Stoffels, B.; Hupa, K.J.; Snoek, S.A.; van Bree, S.; Stein, K.; Schwandt, T.; Vilz, T.O.; Lysson, M.; Veer, C.V.; Kummer, M.P.; et al. Postoperative ileus involves interleukin-1 receptor signaling in enteric glia. Gastroenterology 2014, 146, 176–187.e1. [Google Scholar] [CrossRef]
  121. Lopez-Gomez, L.; Szymaszkiewicz, A.; Zielinska, M.; Abalo, R. Nutraceuticals and Enteric Glial Cells. Molecules 2021, 26, 3762. [Google Scholar] [CrossRef] [PubMed]
  122. Costa, D.V.S.; Bon-Frauches, A.C.; Silva, A.; Lima-Junior, R.C.P.; Martins, C.S.; Leitao, R.F.C.; Freitas, G.B.; Castelucci, P.; Bolick, D.T.; Guerrant, R.L.; et al. 5-Fluorouracil Induces Enteric Neuron Death and Glial Activation During Intestinal Mucositis via a S100B-RAGE-NFkappaB-Dependent Pathway. Sci. Rep. 2019, 9, 665. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  123. Esposito, G.; Capoccia, E.; Turco, F.; Palumbo, I.; Lu, J.; Steardo, A.; Cuomo, R.; Sarnelli, G.; Steardo, L. Palmitoylethanolamide improves colon inflammation through an enteric glia/toll like receptor 4-dependent PPAR-α activation. Gut 2014, 63, 1300–1312. [Google Scholar] [CrossRef]
  124. Sarnelli, G.; Seguella, L.; Pesce, M.; Lu, J.; Gigli, S.; Bruzzese, E.; Lattanzi, R.; D’Alessandro, A.; Cuomo, R.; Steardo, L.; et al. HIV-1 Tat-induced diarrhea is improved by the PPARalpha agonist, palmitoylethanolamide, by suppressing the activation of enteric glia. J. Neuroinflamm. 2018, 15, 94. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  125. Von Boyen, G.B.T.; Steinkamp, M.; Geerling, I.; Reinshagen, M.; Schäfer, K.H.; Adler, G.; Kirsch, J. Proinflammatory Cytokines Induce Neurotrophic Factor Expression in Enteric Glia. Inflamm. Bowel Dis. 2006, 12, 346–354. [Google Scholar] [CrossRef] [PubMed]
  126. Meir, M.; Burkard, N.; Ungewiss, H.; Diefenbacher, M.; Flemming, S.; Kannapin, F.; Germer, C.T.; Schweinlin, M.; Metzger, M.; Waschke, J.; et al. Neurotrophic factor GDNF regulates intestinal barrier function in inflammatory bowel disease. J. Clin. Investig. 2019, 129, 2824–2840. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  127. Zhang, D.K.; He, F.Q.; Li, T.K.; Pang, X.H.; Cui, D.J.; Xie, Q.; Huang, X.L.; Gan, H.T. Glial-derived neurotrophic factor regulates intestinal epithelial barrier function and inflammation and is therapeutic for murine colitis. J. Pathol. 2010, 222, 213–222. [Google Scholar] [CrossRef]
  128. Stavely, R.; Hotta, R.; Picard, N.; Rahman, A.A.; Pan, W.; Bhave, S.; Omer, M.; Ho, W.L.N.; Guyer, R.A.; Goldstein, A.M. Schwann cells in the subcutaneous adipose tissue have neurogenic potential and can be used for regenerative therapies. Sci. Transl. Med. 2022, 14, eabl8753. [Google Scholar] [CrossRef]
  129. Cheng, L.S.; Hotta, R.; Graham, H.K.; Belkind-Gerson, J.; Nagy, N.; Goldstein, A.M. Postnatal human enteric neuronal progenitors can migrate, differentiate, and proliferate in embryonic and postnatal aganglionic gut environments. Pediatr. Res. 2017, 81, 838–846. [Google Scholar] [CrossRef]
  130. Cooper, J.E.; McCann, C.J.; Natarajan, D.; Choudhury, S.; Boesmans, W.; Delalande, J.M.; Vanden Berghe, P.; Burns, A.J.; Thapar, N. In Vivo Transplantation of Enteric Neural Crest Cells into Mouse Gut; Engraftment, Functional Integration and Long-Term Safety. PLoS ONE 2016, 11, e0147989. [Google Scholar] [CrossRef] [Green Version]
  131. Fattahi, F.; Steinbeck, J.A.; Kriks, S.; Tchieu, J.; Zimmer, B.; Kishinevsky, S.; Zeltner, N.; Mica, Y.; El-Nachef, W.; Zhao, H.; et al. Deriving human ENS lineages for cell therapy and drug discovery in Hirschsprung disease. Nature 2016, 531, 105–109. [Google Scholar] [CrossRef] [Green Version]
  132. Hotta, R.; Cheng, L.S.; Graham, H.K.; Pan, W.; Nagy, N.; Belkind-Gerson, J.; Goldstein, A.M. Isogenic enteric neural progenitor cells can replace missing neurons and glia in mice with Hirschsprung disease. Neurogastroenterol. Motil. 2016, 28, 498–512. [Google Scholar] [CrossRef] [Green Version]
  133. Stavely, R.; Abalo, R.; Nurgali, K. Targeting Enteric Neurons and Plexitis for the Management of Inflammatory Bowel Disease. Curr. Drug Targets 2020, 21, 1428–1439. [Google Scholar] [CrossRef] [PubMed]
  134. Fan, Y.; Hackland, J.; Baggiolini, A.; Hung, L.Y.; Zhao, H.; Zumbo, P.; Oberst, P.; Minotti, A.P.; Hergenreder, E.; Najjar, S.; et al. hPSC-derived sacral neural crest enables rescue in a severe model of Hirschsprung’s disease. Cell Stem Cell 2023, 30, 264–282.e9. [Google Scholar] [CrossRef]
  135. Hotta, R.; Natarajan, D.; Burns, A.J.; Thapar, N. Cellular-Based Therapies for Paediatric GI Motility Disorders. In Pediatric Neurogastroenterology: Gastrointestinal Motility Disorders and Disorders of Gut Brain Interaction in Children; Faure, C., Thapar, N., Di Lorenzo, C., Eds.; Springer International Publishing: Cham, Switzerland, 2022; pp. 617–629. [Google Scholar] [CrossRef]
  136. Heuckeroth, R.O. Hirschsprung disease—Integrating basic science and clinical medicine to improve outcomes. Nat. Rev. Gastroenterol. Hepatol. 2018, 15, 152–167. [Google Scholar] [CrossRef]
  137. Watanabe, Y.; Ito, F.; Ando, H.; Seo, T.; Kaneko, K.; Harada, T.; Iino, S. Morphological investigation of the enteric nervous system in Hirschsprung’s disease and hypoganglionosis using whole-mount colon preparation. J. Pediatr. Surg. 1999, 34, 445–449. [Google Scholar] [CrossRef] [PubMed]
  138. Pan, W.; Rahman, A.A.; Stavely, R.; Bhave, S.; Guyer, R.; Omer, M.; Picard, N.; Goldstein, A.M.; Hotta, R. Schwann Cells in the Aganglionic Colon of Hirschsprung Disease Can Generate Neurons for Regenerative Therapy. Stem Cells Transl. Med. 2022, 11, 1232–1244. [Google Scholar] [CrossRef]
  139. Wilkinson, D.J.; Bethell, G.S.; Shukla, R.; Kenny, S.E.; Edgar, D.H. Isolation of Enteric Nervous System Progenitor Cells from the Aganglionic Gut of Patients with Hirschsprung’s Disease. PLoS ONE 2015, 10, e0125724. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  140. Soret, R.; Lassoued, N.; Bonnamour, G.; Bernas, G.; Barbe, A.; Pelletier, M.; Aichi, M.; Pilon, N. Genetic Background Influences Severity of Colonic Aganglionosis and Response to GDNF Enemas in the Holstein Mouse Model of Hirschsprung Disease. Int. J. Mol. Sci. 2021, 22, 13140. [Google Scholar] [CrossRef] [PubMed]
  141. Soret, R.; Schneider, S.; Bernas, G.; Christophers, B.; Souchkova, O.; Charrier, B.; Righini-Grunder, F.; Aspirot, A.; Landry, M.; Kembel, S.W.; et al. Glial Cell Derived Neurotrophic Factor Induces Enteric Neurogenesis and Improves Colon Structure and Function in Mouse Models of Hirschsprung Disease. Gastroenterology 2020, 159, 1824–1838.e17. [Google Scholar] [CrossRef]
  142. Hosoda, K.; Hammer, R.E.; Richardson, J.A.; Baynash, A.G.; Cheung, J.C.; Giaid, A.; Yanagisawa, M. Targeted and natural (piebald-lethal) mutations of endothelin-B receptor gene produce megacolon associated with spotted coat color in mice. Cell 1994, 79, 1267–1276. [Google Scholar] [CrossRef] [PubMed]
  143. Soret, R.; Mennetrey, M.; Bergeron, K.F.; Dariel, A.; Neunlist, M.; Grunder, F.; Faure, C.; Silversides, D.W.; Pilon, N. A collagen VI-dependent pathogenic mechanism for Hirschsprung’s disease. J. Clin. Investig. 2015, 125, 4483–4496. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  144. Bergeron, K.F.; Cardinal, T.; Toure, A.M.; Beland, M.; Raiwet, D.L.; Silversides, D.W.; Pilon, N. Male-Biased Aganglionic Megacolon in the TashT Mouse Line Due to Perturbation of Silencer Elements in a Large Gene Desert of Chromosome 10. PLoS Genet. 2015, 11, e1005093. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  145. Toure, A.M.; Charrier, B.; Pilon, N. Male-specific colon motility dysfunction in the TashT mouse line. Neurogastroenterol. Motil. 2016, 28, 1494–1507. [Google Scholar] [CrossRef]
  146. Montanari, M.; Imbriani, P.; Bonsi, P.; Martella, G.; Peppe, A. Beyond the Microbiota: Understanding the Role of the Enteric Nervous System in Parkinson’s Disease from Mice to Human. Biomedicines 2023, 11, 1560. [Google Scholar] [CrossRef]
  147. Videlock, E.J.; Xing, T.; Yehya, A.H.S.; Travagli, R.A. Experimental models of gut-first Parkinson’s disease: A systematic review. Neurogastroenterol. Motil. 2023, 35, e14604. [Google Scholar] [CrossRef]
  148. Braak, H.; Del Tredici, K.; Rub, U.; de Vos, R.A.; Jansen Steur, E.N.; Braak, E. Staging of brain pathology related to sporadic Parkinson’s disease. Neurobiol. Aging 2003, 24, 197–211. [Google Scholar] [CrossRef]
  149. Lopez-Pingarron, L.; Almeida, H.; Soria-Aznar, M.; Reyes-Gonzales, M.C.; Terron, M.P.; Garcia, J.J. Role of Oxidative Stress on the Etiology and Pathophysiology of Amyotrophic Lateral Sclerosis (ALS) and Its Relation with the Enteric Nervous System. Curr. Issues Mol. Biol. 2023, 45, 3315–3332. [Google Scholar] [CrossRef]
  150. Pattle, S.B.; O’Shaughnessy, J.; Kantelberg, O.; Rifai, O.M.; Pate, J.; Nellany, K.; Hays, N.; Arends, M.J.; Horrocks, M.H.; Waldron, F.M.; et al. pTDP-43 aggregates accumulate in non-central nervous system tissues prior to symptom onset in amyotrophic lateral sclerosis: A case series linking archival surgical biopsies with clinical phenotypic data. J. Pathol. Clin. Res. 2023, 9, 44–55. [Google Scholar] [CrossRef]
  151. Zhang, Y.; Ogbu, D.; Garrett, S.; Xia, Y.; Sun, J. Aberrant enteric neuromuscular system and dysbiosis in amyotrophic lateral sclerosis. Gut Microbes 2021, 13, 1996848. [Google Scholar] [CrossRef]
  152. Geng, Z.H.; Zhu, Y.; Li, Q.L.; Zhao, C.; Zhou, P.H. Enteric Nervous System: The Bridge Between the Gut Microbiota and Neurological Disorders. Front. Aging Neurosci. 2022, 14, 810483. [Google Scholar] [CrossRef] [PubMed]
  153. Clairembault, T.; Kamphuis, W.; Leclair-Visonneau, L.; Rolli-Derkinderen, M.; Coron, E.; Neunlist, M.; Hol, E.M.; Derkinderen, P. Enteric GFAP expression and phosphorylation in Parkinson’s disease. J. Neurochem. 2014, 130, 805–815. [Google Scholar] [CrossRef] [PubMed]
  154. Clairembault, T.; Leclair-Visonneau, L.; Neunlist, M.; Derkinderen, P. Enteric glial cells: New players in Parkinson’s disease? Mov. Disord. 2015, 30, 494–498. [Google Scholar] [CrossRef] [PubMed]
Figure 1. Tissue distribution of the 4 topo-morphological subtypes of EGCs in murine duodenum at P20. (A,B) Double immunofluorescence staining of S100β-positive EGCs and βIII-Tubulin-positive enteric neurons and nerve fibers at the level of myenteric ganglia (A) and circular muscle layer (B). As indicated by arrows, EGCs Type 1 are located in myenteric ganglia, Type II in thick interganglionic nerve fibers, while Type III and Type IV are both associated with thin extraganglionic neuronal fibers. Scale bar, 50 µm.
Figure 1. Tissue distribution of the 4 topo-morphological subtypes of EGCs in murine duodenum at P20. (A,B) Double immunofluorescence staining of S100β-positive EGCs and βIII-Tubulin-positive enteric neurons and nerve fibers at the level of myenteric ganglia (A) and circular muscle layer (B). As indicated by arrows, EGCs Type 1 are located in myenteric ganglia, Type II in thick interganglionic nerve fibers, while Type III and Type IV are both associated with thin extraganglionic neuronal fibers. Scale bar, 50 µm.
Ijms 24 12475 g001
Figure 2. Distribution of SLC18A2 protein in the myenteric plexus of WT mice at P10. Triple immunofluorescence staining shows that SLC18A2 predominantly labels SOX10-positive EGCs Type 1, but also SOX10-negative EGCs Type II and Type III (see arrows in merge panel). βIII-Tubulin labels enteric neurons and nerve fibers. Scale bar, 100 µm.
Figure 2. Distribution of SLC18A2 protein in the myenteric plexus of WT mice at P10. Triple immunofluorescence staining shows that SLC18A2 predominantly labels SOX10-positive EGCs Type 1, but also SOX10-negative EGCs Type II and Type III (see arrows in merge panel). βIII-Tubulin labels enteric neurons and nerve fibers. Scale bar, 100 µm.
Ijms 24 12475 g002
Table 1. Topo-morphological subtypes of EGCs in mice *.
Table 1. Topo-morphological subtypes of EGCs in mice *.
EGC SubtypeAnatomical RegionTopological and Morphological Features
Type IMyenteric and submucosal plexusesWithin myenteric and submucosal ganglia; composed of multiple irregular and highly branched processes, terminating with end-feet like structures and contacting multiple EGCs and neurons. Also named “protoplasmic”.
Type IIMyenteric and submucosal plexusesLocated within or at the border of interganglionic fibers; exhibiting long parallel processes extending along interganglionic fibers without ensheathing them. Also named “fibrous”.
Type III(MP/SMP)Myenteric and submucosal plexusesOutside ganglia and interganglionic fibers, but lying in the same plane; displaying four major processes with secondary branching, closely associated with thin neuronal fibers or small blood vessels.
Type III(Mucosa)Lamina propria
Type IVCircular and longitudinal smooth muscle layersAssociated with thin nerve fibers in the muscularis; characterized by two unbranched processes extending parallelly along nerve fibers. Also named “bipolar”.
* Based on. [23,24].
Table 2. Functional subtypes of EGCs in mice.
Table 2. Functional subtypes of EGCs in mice.
ReferencesCharacterized FunctionFunctional Specialization of EGC Subtypes
Boesmans et al., 2015 [23]Calcium responsiveness to ATP stimulationIn the adult mouse colon, the topo-morphological types I, II and III from myenteric plexus display subtype-specific calcium responsiveness, with Type I EGCs being the most responsive and Type III being the least responsive to purinergic receptor stimulation.
Seguella et al., 2022 [25]Calcium responsiveness to ADP and CCK
stimulation
Type I EGCs exhibit four distinct profiles of calcium responsiveness to ADP and CCK stimulation (ADPHigh/CCKHigh, ADPHigh/CCKLow, ADPLow/CCKHigh, ADPLow/CCKLow) in adult mice, this local diversity being also differentially distributed between duodenum and colon (regional diversity).
Baghdadi et al., 2022 [19]Intestinal epithelium
homeostasis and repair
GFAP+ Type III(Mucosa) EGCs are a key component of the intestinal stem cell niche in the adult murine ileum, being a source of WNT signals important for epithelium homeostasis and repair.
Abbreviations: ADP, adenosine diphosphate; ATP, adenosine triphosphate; CCK, cholecystokinin.
Table 3. Transcriptional subtypes of EGCs in mice and humans.
Table 3. Transcriptional subtypes of EGCs in mice and humans.
ReferencesExperimental ConditionTranscriptional Signatures
Zeisel et al., 2018 [26]scRNA-seq of tdTomato+ cells from small intestine muscles and myenteric plexus of P21 Wnt1-Cre;R26R-tdTomato mice.7 glial clusters (ENTG1-7), including 1 proliferating and 3 expressing Slc18a2.
Drokhlyansky et al., 2020 [13]snRNA-seq of GFP+ nuclei and ribosome-bound RNA from full-thickness small intestine and colon of Sox10-Cre;INTACT, Wnt1-Cre2;INTACT, and Uchl1-H2BmCherry:GFPgpi mice, as a function of age (11–14 weeks vs. 50–52 weeks), sex and circadian phase.3 glial clusters (Glia1-3) enriched in Gfra2, Slc18a2, or Ntsr1 transcripts, respectively. No difference as a function of gut region, age, sex, or circadian phase.
Wright et al., 2021 [27]snRNA-seq of mCherry+ nuclei from distal colon muscles and myenteric plexus of P47-52 Wnt1-Cre;R26R-H2B-mCherry mice.4 glial clusters (Glia1-4); no clearly distinctive features reported.
Baghdadi et al., 2022 [19]Re-analysis of scRNA-seq data generated using colonic mesenchymal cells isolated from the mucosa of adult WT mice [28].3 glial clusters (EGC#0-EGC#2) based on % of Gfap- and Plp1-expressing cells in each cluster: GfapHigh/Plp1Mid, GfapLow/Plp1High, and GfapMid/Plp1Low.
Re-analysis of scRNA-seq data generated using colonic stromal cells isolated from mucosal biopsies of healthy humans and patients with ulcerative colitis (UC), aged between 18 and 90 years [29].4 glial clusters (hEGC#0-EGC#3) based on health status, with hEGC#1 and 2 enriched in healthy samples and hEGC#0 and 3 enriched in UC samples. hEGC#1 corresponds to murine EGC#1 (GfapLow/Plp1High), while hEGC#0 corresponds to murine EGC#0 (GfapHigh/Plp1Mid).
Guyer et al., 2023 [30]scMulti-seq (scRNAseq combined with ATAC-seq) of GFP+ cells from small intestine muscles and myenteric plexus of P14 Plp1-GFP mice.9 transcriptional clusters (clusters #0–8) based on gene expression, chromatin accessibility at neuronal marker peaks, and motif enrichment patterns, including: 2 classified as replicating, 4 with open chromatin, 1 with restricted chromatin and 2 poised for neurogenesis. One of these “neurogenic” clusters is specifically enriched in Slc18a2, Ramp1, and Cpe transcripts.
Schneider et al., 2023 [31]scRNA-seq of GFP+ cells from full-thickness colon of adult Sox10-Cre;INTACT mice kept under restraint stress or not.4 glial clusters, including 1 exclusively present under psychological stress condition, named enteric glia, associated with psychological stress (eGAPS) and highly expressing Nr4a1/2/3.
Abbreviations: ATAC-seq, Transposase-Accessible Chromatin with sequencing; GFP, green fluorescent protein; scRNA-seq, single-cell RNA sequencing; snRNA-seq, single-nucleus RNA sequencing.
Table 4. List of previously reported regulators of enteric gliogenesis in mice.
Table 4. List of previously reported regulators of enteric gliogenesis in mice.
EGC RegulatorRelevant
Expression Pattern
Experimental Evidence
ASCL1 (MASH1)
Transcription factor
NCCs [61], ENS progenitors [62,63], enteric neurons and EGCs [62].In addition to defective neurogenesis, Ascl1−/− embryos have less S100B+ Sox10+ EGCs in ileum and colon. Rescue of enteric neurogenesis but not gliogenesis in Ascl1KINgn2 embryos suggests that ASCL1, which is typically pro-neuronal, also plays an active role in promoting gliogenesis [62].
FOXD3
Transcription factor
NCCs [64,65], SCPs [65], ENS progenitors [66] and EGCs [67].Targeted deletion of Foxd3 in vagal NCC-derived ENS progenitors specifically impairs the formation of S100β+ EGCs in Foxd3flox/−;Ednrb-iCre;R26RYFP+ embryos, leaving neurogenesis virtually unaffected [67].
NR2F1
Transcription factor
NCCs [68] and SCPs [69].Insertional mutagenesis-induced upregulation of Nr2f1 in NCCs leads to premature formation of S100β+ SOX10+ EGCs at the expense of SOX10+ ENS progenitors in Nr2f1Spt/Spt embryos [58].
SOX10
Transcription factor
NCCs [70,71], SCPs [71], ENS progenitors [70,72] and EGCs [51].ENS progenitors from Sox10LacZ/+ embryos precociously express the pan-neuronal marker PGP9.5 [72]. Decreased SOX10 levels attenuate the Hedgehog-induced expression of the EGC marker Fabp7 in Wnt1-Cre;Sufuf/f;Sox10N/+ embryos [59].
TBX3
Transcription factor
NCCs [73], ENS progenitors and enteric neurons [27,74,75].Targeted deletion of Tbx3 in NCCs leads to a marked reduction of S100β+ EGC density in Wnt1-Cre;Tbx3fl/fl embryos. Detection of TBX3 protein in enteric neurons but not in EGCs suggest a non-cell autonomous role [74].
Hedgehog
Signaling pathway
NCCs [76] and ENS progenitors [77] for PTCH1/SMO binding/signaling receptors and GLI nuclear effectors.
Gut epithelium for SHH and IHH ligands [78,79].
Ptch1 deletion-induced activation of Hedgehog signaling in vagal NCCs upregulates the EGC marker Fabp7 in the developing gut of b3-IIIa-Cre;Ptch1f/f embryos, while transduction of CRE in cultured Ptch1f/f ENS progenitors increases the formation of S100β+ EGCs at the expense of TH+ enteric neurons [60]. Tilting the GLIA-vs-GLIR balance toward GLI activation in Wnt1-Cre;Sufuf/f embryos or GLI repression in Gli3Δ699/Δ699 embryos increases or decreases the production of FABP7+ EGCs, respectively [59].
LGI4/ADAM22
Signaling pathway
ENS progenitors and EGCs [80].Mice deficient in either Lgi4 or Adam22 exhibit a similar defect in enteric gliogenesis, characterized by a decreased number of FABP7+ EGCs in vivo and lower GFAP expression in enteric neurosphere assays [80].
Notch
Signaling pathway
NCCs [81,82], SCPs [83] and ENS progenitors [63] for multiple DLL/JAG ligands and Notch receptors.Targeted inhibition of Notch signaling results in a marked decrease of FABP7+ EGCs in Wnt1-Cre;Rbpsuhfl/fl embryos, which is accompanied by a more modest decrease in the number of TuJ1+ enteric neurons [84]. DLL1 treatment of cultured ENS progenitors is sufficient for promoting the formation of GFAP+ EGCs, while DAPT-mediated inhibition of Notch signaling impairs Hedgehog-induced gliogenesis in the same system [60].
NRG/ERBB
Signaling pathway
NCCs [85], SCPs [86], ENS progenitors and EGCs for ERBB3 receptor [87].
Gut mesenchyme for NRG1 (GGF2) ligand [87,88].
S100β staining suggest that both SCPs and EGCs are absent in erbB3/ embryos [89]. NRG1 (GGF2) treatment of cultured ENS progenitors promote their differentiation in GFAP+ EGCs, this effect being increased by pre-treatment with BMP4 [87].
Table 5. Multipotency analyses of mature EGCs in mice.
Table 5. Multipotency analyses of mature EGCs in mice.
ReferencesExperimental ConditionRelevant Results
Joseph et al., 2011 [113]CD49b+ EGCs sorted from the small intestine (muscles and myenteric plexus) of adult WT mice.Sorted CD49b+ cells express glial markers (GFAP, SOX10, S100β, p75, and Nestin) and can be cultured as self-renewing neurospheres that differentiate in peripherin+ neurons, GFAP+ EGCs and α-SMA+ myofibroblasts.
BrdU incorporation assays in the small intestine of adult WT mice (and rats) housed in normal conditions or exposed to various potential triggers of neurogenesis (e.g., DSS-induced inflammation, BAC-induced focal aganglionosis).Basal enteric gliogenesis is detectable under steady-state condition, becoming markedly increased after certain types of injury (up to 90% of S100β+ were also BrdU+ in BAC-ablated regions). No evidence of neurogenesis, with exception of a single rat (out of 85 rodents in total) in which 6.1% of HuC/D+ myenteric neurons did incorporate BrdU in BAC-ablated region.
Cell lineage tracing in the small intestine of adult GFAP-Cre;R26R-YFP or GFAP-CreERT2;R26R-YFP mice, exposed to BAC treatment or not.With the constitutive Cre driver line, 6–7% of HuC/D+ myenteric neurons were also YFP+ in both control and BAC-treated mice. This most likely reflects an early fetal/neonatal contribution from a GFAP+ progenitor, which was no longer detectable when the tamoxifen-inducible Cre driver was activated in adults (<0.1% of HuC/D+ also YFP+ in this case).
Laranjeira et al., 2011 [116]Cultures of enzymatically dissociated small intestine (muscles and myenteric plexus) from tamoxifen-treated adult Sox10-iCreERT2;R26R-YFP or hGFAP-CreERT2;R26R-YFP mice.YFP+ cells generate bipotential SOX10+ PHOX2B+ ASCL1+ ENS progenitors that can be cultured as self-renewing neurospheres, and can be differentiated in GFAP+ EGCs and multiple neuronal subtypes (nNOS+, VIP+, or NPY+).
Cell lineage tracing studies in the small intestine of adult Sox10-iCreERT2;R26R-YFP mice, exposed to BAC treatment or not.YFP+ HuC/D+ myenteric neurons are not detected following tamoxifen treatment under steady-state conditions but are readily detected upon BAC-mediated ENS ablation.
Belkind-Gerson et al., 2013 [117]Neurospheres prepared from enzymatically dissociated colon (mucosa and submucosal plexus vs. muscles and myenteric plexus) of Nestin-GFP mice.GFP+ cells co-express glial markers (S100β, GFAP) in vivo, and generate neurospheres containing TuJ1+ neurons and S100β+ EGCs that both co-express GFP in culture.
Belkind-Gerson et al., 2015 [115]Pseudo cell lineage tracing studies in colon of Sox2-GFP and Nestin-GFP mice, exposed to DSS treatment or not.In absence of DSS, GFP expression is virtually undetectable in HuC/D+ myenteric neurons but becomes detectable 48 h after DSS treatment (8% of neurons in Sox2-GFP vs. 1.8% in Nestin-GFP mice).
Culture of CD49+ EGCs sorted from small intestine and colon (muscles and myenteric plexus) of adult mice, in absence or presence of a serotonin receptor antagonist Sorted CD49b+ EGCs generate TuJ1+ neurons, GFAP+ EGCs and TuJ1+ GFAP+ neuroglial cells in culture. The serotonin receptor antagonist increases the proportion of these neuroglial cells at the expense of neurons.
Transplantation of neurospheres derived from CD49b+ EGCs in explants of aneural embryonic chick hindgutTransplanted neurospheres generate TuJ1+ neurons and GFAP+ EGCs in both myenteric and submucosal plexus.
Belkind-Gerson et al., 2017 [114]Cell lineage tracing studies in colon of adult Sox2-CreERT2:R26R-YFP and Plp1-CreERT2:R26R-tdTomato mice, exposed to DSS treatment or not.DSS treatment increases the proportion of HuC/D+ myenteric and submucosal neurons co-expressing either of the fluorescent reporters in tamoxifen-induced mice.
Neurospheres prepared from enzymatically dissociated colon (full thickness) of adult tamoxifen-treated Plp1-CreERT2;R26R-tdTomato mice.tdTomato is expressed in neurons (either TuJ1+, HuC/D+, or PGP9.5+), EGCs (either SOX2+ or S100β+), and neuroglial cells co-expressing neuronal and glial markers.
Guyer et al., 2023 [30]Neurospheres prepared from enzymatically dissociated small intestine (muscles and myenteric plexus) of adult Plp1-GFP;Actl6b-Cre;R26R-tdTomato dual reporter mice.GFP+ EGCs sorted from neurospheres generate new tdTomato+ neurons in culture.
Sorted tdTomato-negative cells from small intestine (muscles and myenteric plexus) of adult Actl6b-Cre;R26R-tdTomato mice.Neurospheres derived from sorted tdTomato-negative cells generate new tdTomato+ neurons in culture.
Abbreviations: BAC, benzalkonium chloride; BrdU, bromodeoxyuridine; DSS, dextran sodium sulfate.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Lefèvre, M.A.; Soret, R.; Pilon, N. Harnessing the Power of Enteric Glial Cells’ Plasticity and Multipotency for Advancing Regenerative Medicine. Int. J. Mol. Sci. 2023, 24, 12475. https://doi.org/10.3390/ijms241512475

AMA Style

Lefèvre MA, Soret R, Pilon N. Harnessing the Power of Enteric Glial Cells’ Plasticity and Multipotency for Advancing Regenerative Medicine. International Journal of Molecular Sciences. 2023; 24(15):12475. https://doi.org/10.3390/ijms241512475

Chicago/Turabian Style

Lefèvre, Marie A., Rodolphe Soret, and Nicolas Pilon. 2023. "Harnessing the Power of Enteric Glial Cells’ Plasticity and Multipotency for Advancing Regenerative Medicine" International Journal of Molecular Sciences 24, no. 15: 12475. https://doi.org/10.3390/ijms241512475

APA Style

Lefèvre, M. A., Soret, R., & Pilon, N. (2023). Harnessing the Power of Enteric Glial Cells’ Plasticity and Multipotency for Advancing Regenerative Medicine. International Journal of Molecular Sciences, 24(15), 12475. https://doi.org/10.3390/ijms241512475

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop