Psychological stress induces an increase in cholinergic enteric neuromuscular pathways mediated by glucocorticoid receptors.

Introduction: Repeated acute stress (RASt) is known to be associated with gastrointestinal dysfunctions. However, the mechanisms underlying these effects have not yet been fully understood. While glucocorticoids are clearly identified as stress hormones, their involvement in RASt-induced gut dysfunctions remains unclear, as does the function of glucocorticoid receptors (GR). The aim of our study was to evaluate the involvement of GR on RASt-induced changes in gut motility, particularly through the enteric nervous system (ENS). Methods: Using a murine water avoidance stress (WAS) model, we characterized the impact of RASt upon the ENS phenotype and colonic motility. We then evaluated the expression of glucocorticoid receptors in the ENS and their functional impact upon RASt-induced changes in ENS phenotype and motor response. Results: We showed that GR were expressed in myenteric neurons in the distal colon under basal conditions, and that RASt enhanced their nuclear translocation. RASt increased the proportion of ChAT-immunoreactive neurons, the tissue concentration of acetylcholine and enhanced cholinergic neuromuscular transmission as compared to controls. Finally, we showed that a GR-specific antagonist (CORT108297) prevented the increase of acetylcholine colonic tissue level and in vivo colonic motility. Discussion: Our study suggests that RASt-induced functional changes in motility are, at least partly, due to a GR-dependent enhanced cholinergic component in the ENS.

Could the Microbiota Be a Predictive Factor for the Clinical Response to Probiotic Supplementation in IBS-D? A Cohort Study.

BACKGROUND: Increasing evidence suggests the beneficial effects of probiotics in irritable bowel syndrome (IBS), but little is known about how they can impact the gut microbiota. Our objective was to evaluate the effects of a multistrain probiotic on IBS symptoms, gut permeability and gut microbiota in patients with diarrhoea-predominant IBS (IBS-D). METHODS: Adults with IBS-D were enrolled in an open-label trial to receive a multistrain probiotic for 4 weeks. Abdominal pain, stool frequency, quality of life, gut permeability, and the luminal and adherent microbiota from colonic biopsies were evaluated before and after supplementation. RESULTS: Probiotics significantly improved symptoms and quality of life, despite having no impact on permeability in the global population. In the population stratified by the response, the diarrhoea responders displayed reduced colonic permeability after supplementation. The luminal and adherent microbiota were specifically altered depending on the patients' clinical responses regarding pain and diarrhoea. Interestingly, we identified a microbial signature in IBS-D patients that could predict a response or lack of response to supplementation. CONCLUSIONS: The multistrain probiotic improved the symptoms of IBS-D patients and induced distinct effects on the gut microbiota according to the patient's clinical response and initial microbiota composition. Our study further supports the need to develop individualised probiotic-based approaches regarding IBS.

Late-Stage Glioma Is Associated with Deleterious Alteration of Gut Bacterial Metabolites in Mice.

Brain-gut axis refers to the bidirectional functional connection between the brain and the gut, which sustains vital functions for vertebrates. This connection also underlies the gastrointestinal (GI) comorbidities associated with brain disorders. Using a mouse model of glioma, based on the orthotopic injection of GL261 cell line in syngeneic C57BL6 mice, we show that late-stage glioma is associated with GI functional alteration and with a shift in the level of some bacterial metabolites in the cecum. By performing cecal content transfer experiments, we further show that cancer-associated alteration in cecal metabolites is involved in end-stage disease progression. Antibiotic treatment results in a slight but significant delay in mice death and a shift in the proportion of myeloid cells in the brain tumor environment. This work rationally considers microbiota modulating strategies in the clinical management of patients with late-stage glioma.

Maternal prebiotic supplementation impacts colitis development in offspring mice.

Background and aims: Maternal diet plays a key role in preventing or contributing to the development of chronic diseases, such as obesity, allergy, and brain disorders. Supplementation of maternal diet with prebiotics has been shown to reduce the risk of food allergies and affect the intestinal permeability in offspring later in life. However, its role in modulating the development of other intestinal disorders, such as colitis, remains unknown. Therefore, we investigated the effects of prebiotic supplementation in pregnant mice on the occurrence of colitis in their offspring. Materials and methods: Offspring from mothers, who were administered prebiotic galacto-oligosaccharides and inulin during gestation or fed a control diet, were subjected to three cycles of dextran sulphate sodium (DSS) treatment to induce chronic colitis, and their intestinal function and disease activity were evaluated. Colonic remodelling, gut microbiota composition, and lipidomic and transcriptomic profiles were also assessed. Results: DSS-treated offspring from prebiotic-fed mothers presented a higher disease score, increased weight loss, and increased faecal humidity than those from standard diet-fed mothers. DSS-treated offspring from prebiotic-fed mothers also showed increased number of colonic mucosal lymphocytes and macrophages than the control group, associated with the increased colonic concentrations of resolvin D5, protectin DX, and 14-hydroxydocosahexaenoic acid, and modulation of colonic gene expression. In addition, maternal prebiotic supplementation induced an overabundance of eight bacterial families and a decrease in the butyrate caecal concentration in DSS-treated offspring. Conclusion: Maternal prebiotic exposure modified the microbiota composition and function, lipid content, and transcriptome of the colon of the offspring. These modifications did not protect against colitis, but rather sensitised the mice to colitis development.

The ephrin receptor EphB2 regulates the connectivity and activity of enteric neurons.

Highly organized circuits of enteric neurons are required for the regulation of gastrointestinal functions, such as peristaltism or migrating motor complex. However, the factors and molecular mechanisms that regulate the connectivity of enteric neurons and their assembly into functional neuronal networks are largely unknown. A better understanding of the mechanisms by which neurotrophic factors regulate this enteric neuron circuitry is paramount to understanding enteric nervous system (ENS) physiology. EphB2, a receptor tyrosine kinase, is essential for neuronal connectivity and plasticity in the brain, but so far its presence and function in the ENS remain largely unexplored. Here we report that EphB2 is expressed preferentially by enteric neurons relative to glial cells throughout the gut in rats. We show that in primary enteric neurons, activation of EphB2 by its natural ligand ephrinB2 engages ERK signaling pathways. Long-term activation with ephrinB2 decreases EphB2 expression and reduces molecular and functional connectivity in enteric neurons without affecting neuronal density, ganglionic fiber bundles, or overall neuronal morphology. This is highlighted by a loss of neuronal plasticity markers such as synapsin I, PSD95, and synaptophysin, and a decrease of spontaneous miniature synaptic currents. Together, these data identify a critical role for EphB2 in the ENS and reveal a unique EphB2-mediated molecular program of synapse regulation in enteric neurons.

A murine model to study the gut bacteria parameters during complex antibiotics like cefotaxime and ceftriaxone treatment.

BACKGROUND: The globally increasing resistance due to extended-spectrum beta-lactamase producing Enterobacteriaceae is a major concern. The objective of this work was to develop a murine model to study the gut bacteria parameters during complex antibiotics like cefotaxime and ceftriaxone treatment and to compare the fecal carriage of ESBL-producing Enterobacteriaceae. METHODS: SWISS mice were treated either with ceftriaxone or with cefotaxime or with NaCl 0.9% as a control group from day 1 to day 5. We performed a gavage at day 4 with a Klebsiella pneumonia CTX-M9. We collected stools and performed pharmacological measurements, cultures and 16S rRNA gene amplification and sequencing during the 12 days of the stool collection. RESULTS: Mice treated with ceftriaxone were more colonized than mice treated with cefotaxime after gavage (p-value = 0.008; Kruskal-Wallis test). Ceftriaxone and cefotaxime were both excreted in large quantity in gut lumen but they drove architecture of the gut microbiota in different trajectories. Highest levels of colonization were associated with particular microbiota composition using principal coordinate analysis (PCoA) which were more often achieved in ceftriaxone-treated mice and which were preceded by highest fecal antibiotics concentrations in both cefotaxime or ceftriaxone groups. Using LEfSe, we found that twelve taxa were significantly different between cefotaxime and ceftriaxone-treated mice. Using SplinectomeR, we found that relative abundances of Klebsiella were significantly higher in CRO than in CTX-treated mice (p-value = 0.01). CONCLUSION: Ceftriaxone selects a particular microbial community and its substitution for cefotaxime could prevent the selection of extended-spectrum beta-lactamase producing Enterobacteriaceae.

Analysis of enteric nervous system and intestinal epithelial barrier to predict complications in Hirschsprung's disease.

In Hirschsprung's disease (HSCR), postoperative course remains unpredictable. Our aim was to define predictive factors of the main postoperative complications: obstructive symptoms (OS) and Hirschsprung-associated enterocolitis (HAEC). In this prospective multicentre cohort study, samples of resected bowel were collected at time of surgery in 18 neonates with short-segment HSCR in tertiary care hospitals. OS and HAEC were noted during postoperative follow-up. We assessed the enteric nervous system and the intestinal epithelial barrier (IEB) in ganglionic segments by combining immunohistochemical, proteomic and transcriptomic approaches, with functional ex vivo analysis of motility and para/transcellular permeability. Ten HSCR patients presented postoperative complications (median follow-up 23.5 months): 6 OS, 4 HAEC (2 with OS), 2 diarrhoea (without OS/HAEC). Immunohistochemical analysis showed a significant 41% and 60% decrease in median number of nNOS-IR myenteric neurons per ganglion in HSCR with OS as compared to HSCR with HAEC/diarrhoea (without OS) and HSCR without complications (p = 0.0095; p = 0.002, respectively). Paracellular and transcellular permeability was significantly increased in HSCR with HAEC as compared to HSCR with OS/diarrhoea without HAEC (p = 0.016; p = 0.009) and HSCR without complications (p = 0.029; p = 0.017). This pilot study supports the hypothesis that modulating neuronal phenotype and enhancing IEB permeability may treat or prevent postoperative complications in HSCR.

Environmental enrichment alleviates the deleterious effects of stress in experimental autoimmune encephalomyelitis.

BACKGROUND: Clinical observations support the hypothesis that stressful events increase relapse occurrence in multiple sclerosis patients, while stress-reduction strategies can modulate this effect. However, a direct cause-effect relationship between stress level and relapse cannot be firmly established from these data. OBJECTIVES: The purpose of this work was to address whether modulation of stress could interfere with symptom relapse in an animal model of multiple sclerosis with relapsing-remitting course. METHODS: Mice bred in standard or enriched environment were subjected to repeated acute stress during the remission phase of relapsing-remitting PLP-induced experimental autoimmune encephalomyelitis. RESULTS: We report that repeated acute stress induced a twofold increase in relapse incidence in experimental autoimmune encephalomyelitis. On the other hand, environmental enrichment reduced relapse incidence and severity, and reversed the effects of repeated acute stress. CONCLUSION: These data provide the platform for further studies on the biological processes that link stress and multiple sclerosis relapses in a suitable animal model.

Bidirectional gut-to-brain and brain-to-gut propagation of synucleinopathy in non-human primates.

In Parkinson's disease, synucleinopathy is hypothesized to spread from the enteric nervous system, via the vagus nerve, to the CNS. Here, we compare, in baboon monkeys, the pathological consequences of either intrastriatal or enteric injection of α-synuclein-containing Lewy body extracts from patients with Parkinson's disease. This study shows that patient-derived α-synuclein aggregates are able to induce nigrostriatal lesions and enteric nervous system pathology after either enteric or striatal injection in a non-human primate model. This finding suggests that the progression of α-synuclein pathology might be either caudo-rostral or rostro-caudal, varying between patients and disease subtypes. In addition, we report that α-synuclein pathological lesions were not found in the vagal nerve in our experimental setting. This study does not support the hypothesis of a transmission of α-synuclein pathology through the vagus nerve and the dorsal motor nucleus of the vagus. Instead, our results suggest a possible systemic mechanism in which the general circulation would act as a route for long-distance bidirectional transmission of endogenous α-synuclein between the enteric and the central nervous systems. Taken together, our study provides invaluable primate data exploring the role of the gut-brain axis in the initiation and propagation of Parkinson's disease pathology and should open the door to the development and testing of new therapeutic approaches aimed at interfering with the development of sporadic Parkinson's disease.

Enteric Nervous System Remodeling in a Rat Model of Spinal Cord Injury: A Pilot Study.

The physiopathology of digestive disorders in patients with spinal cord injury (SCI) remains largely unknown, particularly the involvement of the enteric nervous system (ENS). We aimed in a rat model of chronic thoracic SCI to characterize (1) changes in the neurochemical coding of enteric neurons and their putative consequences upon neuromuscular response, and (2) the inflammatory response of the colon. Ex vivo motility of proximal and distal colon segments of SCI and control (CT) rats were studied in an organ chamber in response to electrical field stimulation (EFS) and bethanechol. Immunohistochemical analysis of proximal and distal segments was performed using antibodies again Hu, neuronal nitric oxide synthase, (nNOS), and choline acetyltransferase. Colonic content of acetylcholine and acetylcholinesterase was measured; messenger RNA (mRNA) expression of inflammatory cytokines was measured using reverse transcription quantitative polymerase chain reaction (RT-qPCR) approaches. Compared with the CT rats, the contractile response to bethanechol was significantly decreased in the proximal colon of SCI rats but not in the distal colon. The proportion of nNOS immunoreactive (IR) neurons was significantly reduced in the proximal but not distal colon of SCI rats. No change in proportion of choline acetyltransferase (ChAT)-IR was reported; the tissue concentration of acetylcholine was significantly decreased in the proximal colon of SCI rats. The expression of tumor necrosis factor alpha (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) was significantly reduced in the proximal and distal colon of SCI rats. This study demonstrates that functional motor and enteric neuroplastic changes affect preferentially the proximal colon compared with the distal colon. The underlying mechanisms and factors responsible for these changes remain to be discovered.

Monomelic Ischemic Neuropathy of the Tibial and Peroneal Nerve After Onyx Embolization of Vasa Nervorum Supplying a Surgically Excluded Popliteal Artery Aneurysm.

Ischemic neuropathy is an exceedingly rare complication after peripheral artery embolization. We report a case of ischemic damage to the tibial and peroneal nerve after embolization of the vasa nervorum that served as feeding collaterals to a surgically excluded popliteal artery aneurysm.

Basal and Spasmolytic Effects of a Hydroethanolic Leaf Extract of Melissa officinalis L. on Intestinal Motility: An Ex Vivo Study.

Melissa officinalis L. (lemon balm) has been used for decades with symptomatic benefits in patients with digestive disorders. However, very little is known on the effects of M. officinalis on the gastrointestinal (GI) tract. In this study, the basal and spasmolytic properties of a hydroethanolic leaf extract (HLE) of M. officinalis were assessed ex vivo on different segments of the GI tract of mice after phytochemical characterization of the extract. M. officinalis HLE had site- and dose-dependent effects on the contractile activity of the GI tract, the motility response being impacted in the jejunum and ileum but not in the antrum and colon. The observed effects could be caused by the phenolic compounds (mainly rosmarinic acid) detected in the extract.

Multi-hit early life adversity affects gut microbiota, brain and behavior in a sex-dependent manner.

The accumulation of adverse events in utero and during childhood differentially increases the vulnerability to psychiatric diseases in men and women. Gut microbiota is highly sensitive to the early environment and has been recently hypothesized to affect brain development. However, the impact of early-life adversity on gut microbiota, notably with regards to sex differences, remains to be explored. We examined the effects of multifactorial early-life adversity on behavior and microbiota composition in C3H/HeN mice of both sexes exposed to a combination of maternal immune activation (lipopolysaccharide injection on embryonic day 17, 120 µg/kg, i.p.), maternal separation (3hr per day from postnatal day (PND)2 to PND14) and maternal unpredictable chronic mild stress. At adulthood, offspring exposed to multi-hit early adversity showed sex-specific behavioral phenotypes with males exhibiting deficits in social behavior and females showing increased anxiety in the elevated plus maze and increased compulsive behavior in the marble burying test. Early adversity also differentially regulated gene expression in the medial prefrontal cortex (mPFC) according to sex. Interestingly, several genes such as Arc, Btg2, Fosb, Egr4 or Klf2 were oppositely regulated by early adversity in males versus females. Finally, 16S-based microbiota profiling revealed sex-dependent gut dysbiosis. In males, abundance of taxa belonging to Lachnospiraceae and Porphyromonadaceae families or other unclassified Firmicutes, but also Bacteroides, Lactobacillus and Alloprevotella genera was regulated by early adversity. In females, the effects of early adversity were limited and mainly restricted to Lactobacillus and Mucispirillum genera. Our work reveals marked sex differences in a multifactorial model of early-life adversity, both on emotional behaviors and gut microbiota, suggesting that sex should systematically be considered in preclinical studies both in neurogastroenterology and psychiatric research.

Maternal protein restriction induces gastrointestinal dysfunction and enteric nervous system remodeling in rat offspring.

Early-life adversity is a major risk factor for the development of diseases later in life. Maternal protein restriction (MPR) is associated with morbidities in offspring affecting multiple organs, but its impact on the gastrointestinal (GI) tract remains poorly studied. Using a rat model, we examined the consequences of MPR on GI function and on the enteric nervous system (ENS) in the offspring at postnatal d 35 under basal state and following a water avoidance stress (WAS). Compared with control rats, MPR rats exhibited greater colonic motility, permeability, and corticosteronemia. In contrast to controls, MPR rats presented a blunted functional and corticosteronemic response to WAS. Furthermore, MPR rats showed an increased proportion of choline acetyltransferase-immunoreactive (ChAT-IR) neurons and a reduced level of autophagy in colonic myenteric neurons. In ENS cultures, corticosterone treatment increased the proportion of ChAT-IR neurons and reduced autophagy level in enteric neurons. Inhibition of autophagy in ENS cultures resulted in a higher vulnerability of enteric neurons to a cellular stress. Altogether, this study suggests that MPR induced GI dysfunction and ENS alterations in offspring rats and that MPR-induced increased corticosteronemia might be involved in ENS remodeling and altered responsiveness of the gut to stressors later in life.-Aubert, P., Oleynikova, E., Rizvi, H., Ndjim, M., Le Berre-Scoul, C., Grohard, P. A., Chevalier, J., Segain, J.-P., Le Drean, G., Neunlist, M., Boudin, H. Maternal protein restriction induces gastrointestinal dysfunction and enteric nervous system remodeling in rat offspring.

Acetylcholine induces stem cell properties of gastric cancer cells of diffuse type.

Gastric cancer is the third leading cause of cancer-related death worldwide, but the mechanisms of gastric carcinogenesis are not completely understood. Recently, the role of cholinergic neuronal pathways in promoting this process has been demonstrated. Our aim was to extend these studies and to evaluate, using an in vitro model of tumorspheres, the effect of acetylcholine on human gastric cancer cells, and the role of acetylcholine receptors and of the nitric oxide pathway, in this effect. The gastric cancer cell line MKN-45 of the diffuse type of gastric cancer was cultured in the presence of acetylcholine, or different agonists or inhibitors of muscarinic and nicotinic acetylcholine receptors, or nitric oxide donor or inhibitor of the nitric oxide pathway, and the number and size of tumorspheres were assessed. The expression of cancer stem cell markers (CD44 and aldehyde dehydrogenase) was also evaluated by immunofluorescence and quantitative reverse transcription polymerase chain reaction. We showed that acetylcholine increased both the number and size of tumorspheres and that this effect was reproduced with both muscarinic and nicotinic acetylcholine receptors agonists and was inhibited by both receptor antagonists. The nitric oxide donor stimulated the tumorsphere formation, while the nitric oxide synthesis inhibitor inhibited the stimulatory effect of acetylcholine. Moreover, acetylcholine increased the expression of stem cell markers on gastric cancer cells. These results indicate that acetylcholine induces the stem cell properties of gastric cancer cells and both muscarinic and nicotinic receptors and a nitrergic pathway might be involved in this effect.

Acid-Hydrolyzed Gliadins Worsen Food Allergies through Early Sensitization.

SCOPE: Food allergies result from a complex immune response involving both innate and adaptive immune cells. Major proteins of wheat flour, gliadins, appear to be important allergens, and their characteristics can influence the allergic response. This study investigates the immune reaction when developing a food allergy to gliadins in native, deamidated, or hydrolyzed forms. METHODS: The immune response after one or two intraperitoneal sensitizations and after oral challenge with each gliadin form is analyzed. RESULTS: Results demonstrate that deamidated gliadins induce a stronger allergic reaction compared to native gliadins. Moreover, deamidation induces an earlier increase in intestinal permeability associated with more pronounced Th2 and Th17 polarizations together with an influx of antigen-presenting cells, especially cDC2. CONCLUSION: Altogether, Results indicate that industrial processes such as deamidation or hydrolysis influences food allergenicity through immune modulation and helps us to develop tools to determine how these processes can influence this reaction and encourage or decrease allergic reactions.

Multi loop snare technique for difficult inferior vena cava filter retrievals.

INTRODUCTION: Use of optional vena cava filters has steadily increased. In the majority of cases removal is successful using standard techniques. In cases of tilting and migration of the filter however, more advanced techniques are necessary. The "loop-snare" technique has been described for such cases. Difficulties arise when the loop starts to slip around the legs and arms of the filter. NEW TECHNIQUE: We present an improved loop-snare technique which allows to retrieve IVC filters when the simple loop-snare technique fails. We used additional loops, in one case one additional loop in another case two additional loops around the filter tip which allowed successful retrieval. The additional loops were created with a reversed shaped catheter. All guidewires were then engaged with a snare and pulled into a large sheath. The additional loops stabilize the tip and the filter can be pulled into the sheath. CONCLUSION: The "multiple-loop-snare" technique is a refinement of the previously described "single loop-snare" technique and can be used when one loop fails.

Anti-inflammatory Effects of Enhanced Recovery Programs on Early-Stage Colorectal Cancer Surgery.

BACKGROUND: Postoperative ileus (POI) is observed in 20-30% of patients undergoing colorectal cancer surgery, despite enhanced recovery programs (ERPs). Cyclooxygenase (COX)-2 is identified as a key enzyme in POI, but other arachidonic acid pathway enzymes have received little attention despite their potential as selective targets to prevent POI. The objectives were to compare the expression of arachidonic acid metabolism (AAM) enzymes (1) between patients who underwent colorectal cancer surgery and followed an ERP or not (NERP), (2) and between ERP patients who experimented POI or not and (3) to determine the ability of antagonists of these pathways to modulate contractile activity of colonic muscle. METHODS: This was a translational study. Main outcome measures were gastrointestinal motility recovery data, mRNA expressions of key enzymes involved in AAM (RT-qPCR) and ex vivo motility values of the circular colon muscle. Twenty-eight prospectively included ERP patients were compared to eleven retrospectively included NERP patients that underwent colorectal cancer surgery. RESULTS: ERP reduced colonic mucosal COX-2, microsomal prostaglandin E synthase (mPGES1) and hematopoietic prostaglandin D synthase (HPGDS) mRNA expression. mPGES1 and HPGDS mRNA expression were significantly associated with ERP compliance (respectively, r2 = 0.25, p = 0.002 and r2 = 0.6, p < 0.001). In muscularis propria, HPGDS mRNA expression was correlated with GI motility recovery (p = 0.002). The pharmacological inhibition of mPGES1 increased spontaneous ex vivo contractile activity in circular muscle (p = 0.03). CONCLUSION: The effects of ERP on GI recovery are correlated with the compliance of ERP and could be mediated at least in part by mPGES1, HPGDS and COX-2. Furthermore, mPGES1 shows promise as a therapeutic target to further reduce POI duration among ERP patients.

Engineered human pluripotent-stem-cell-derived intestinal tissues with a functional enteric nervous system.

The enteric nervous system (ENS) of the gastrointestinal tract controls many diverse functions, including motility and epithelial permeability. Perturbations in ENS development or function are common, yet there is no human model for studying ENS-intestinal biology and disease. We used a tissue-engineering approach with embryonic and induced pluripotent stem cells (PSCs) to generate human intestinal tissue containing a functional ENS. We recapitulated normal intestinal ENS development by combining human-PSC-derived neural crest cells (NCCs) and developing human intestinal organoids (HIOs). NCCs recombined with HIOs in vitro migrated into the mesenchyme, differentiated into neurons and glial cells and showed neuronal activity, as measured by rhythmic waves of calcium transients. ENS-containing HIOs grown in vivo formed neuroglial structures similar to a myenteric and submucosal plexus, had functional interstitial cells of Cajal and had an electromechanical coupling that regulated waves of propagating contraction. Finally, we used this system to investigate the cellular and molecular basis for Hirschsprung's disease caused by a mutation in the gene PHOX2B. This is, to the best of our knowledge, the first demonstration of human-PSC-derived intestinal tissue with a functional ENS and how this system can be used to study motility disorders of the human gastrointestinal tract.

Postnatal development of the myenteric glial network and its modulation by butyrate.

The postnatal period is crucial for the development of gastrointestinal (GI) functions. The enteric nervous system is a key regulator of GI functions, and increasing evidences indicate that 1) postnatal maturation of enteric neurons affect the development of GI functions, and 2) microbiota-derived short-chain fatty acids can be involved in this maturation. Although enteric glial cells (EGC) are central regulators of GI functions, the postnatal evolution of their phenotype remains poorly defined. We thus characterized the postnatal evolution of EGC phenotype in the colon of rat pups and studied the effect of short-chain fatty acids on their maturation. We showed an increased expression of the glial markers GFAP and S100ß during the first postnatal week. As demonstrated by immunohistochemistry, a structured myenteric glial network was observed at 36 days in the rat colons. Butyrate inhibited EGC proliferation in vivo and in vitro but had no effect on glial marker expression. These results indicate that the EGC myenteric network continues to develop after birth, and luminal factors such as butyrate endogenously produced in the colon may affect this development.