Fecal microbiota transplantation enhances cell therapy in a rat model of hypoganglionosis by SCFA-induced MEK1/2 signaling pathway.

Hirschsprung disease (HSCR), one of several neurocristopathies in children, is characterized by nerve loss in the large intestine and is mainly treated by surgery, which causes severe complications. Enteric neural crest-derived cell (ENCC) transplantation is a potential therapeutic strategy; however, so far with poor efficacy. Here, we assessed whether and how fecal microbiota transplantation (FMT) could improve ENCC transplantation in a rat model of hypoganglionosis; a condition similar to HSCR, with less intestinal innervation. We found that the hypoganglionosis intestinal microenvironment negatively influenced the ENCC functional phenotype in vitro and in vivo. Combining 16S rDNA sequencing and targeted mass spectrometry revealed microbial dysbiosis and reduced short-chain fatty acid (SCFA) production in the hypoganglionic gut. FMT increased the abundance of Bacteroides and Clostridium, SCFA production, and improved outcomes following ENCC transplantation. SCFAs alone stimulated ENCC proliferation, migration, and supported ENCC transplantation. Transcriptome-wide mRNA sequencing identified MAPK signaling as the top differentially regulated pathway in response to SCFA exposure, and inhibition of MEK1/2 signaling abrogated the SCFA-mediated effects on ENCC. This study demonstrates that FMT improves cell therapy for hypoganglionosis via short-chain fatty acid metabolism-induced MEK1/2 signaling.

A distinct transcriptome characterizes neural crest-derived cells at the migratory wavefront during enteric nervous system development.

Enteric nervous system development relies on intestinal colonization by enteric neural crest-derived cells (ENCDCs). This is driven by a population of highly migratory and proliferative ENCDCs at the wavefront, but the molecular characteristics of these cells are unknown. ENCDCs from the wavefront and the trailing region were isolated and subjected to RNA-seq. Wavefront-ENCDCs were transcriptionally distinct from trailing ENCDCs, and temporal modelling confirmed their relative immaturity. This population of ENCDCs exhibited altered expression of ECM and cytoskeletal genes, consistent with a migratory phenotype. Unlike trailing ENCDCs, the wavefront lacked expression of genes related to neuronal or glial maturation. As wavefront ENCDC genes were associated with migration and developmental immaturity, the genes that remain expressed in later progenitor populations may be particularly pertinent to understanding the maintenance of ENCDC progenitor characteristics. Dusp6 expression was specifically upregulated at the wavefront. Inhibiting DUSP6 activity prevented wavefront colonization of the hindgut, and inhibited the migratory ability of post-colonized ENCDCs from midgut and postnatal neurospheres. These effects were reversed by simultaneous inhibition of ERK signaling, indicating that DUSP6-mediated ERK inhibition is required for ENCDC migration in mouse and chick.

CXCR4 and CXCL12 signaling regulates the development of extrinsic innervation to the colorectum.

The gastrointestinal tract is innervated by an intrinsic neuronal network, known as the enteric nervous system (ENS), and by extrinsic axons arising from peripheral ganglia. The nerve of Remak (NoR) is an avian-specific sacral neural crest-derived ganglionated structure that extends from the cloaca to the proximal midgut and, similar to the pelvic plexus, provides extrinsic innervation to the distal intestine. The molecular mechanisms controlling extrinsic nerve fiber growth into the gut is unknown. In vertebrates, CXCR4, a cell-surface receptor for the CXCL12 chemokine, regulates migration of neural crest cells and axon pathfinding. We have employed chimeric tissue recombinations and organ culture assays to study the role of CXCR4 and CXCL12 molecules in the development of colorectal innervation. CXCR4 is specifically expressed in nerve fibers arising from the NoR and pelvic plexus, while CXCL12 is localized to the hindgut mesenchyme and enteric ganglia. Overexpression of CXCL12 results in significantly enhanced axonal projections to the gut from the NoR, while CXCR4 inhibition disrupts nerve fiber extension, supporting a previously unreported role for CXCR4 and CXCL12 signaling in extrinsic innervation of the colorectum.

Endothelin signaling in development.

Since the discovery of endothelin 1 (EDN1) in 1988, the role of endothelin ligands and their receptors in the regulation of blood pressure in normal and disease states has been extensively studied. However, endothelin signaling also plays crucial roles in the development of neural crest cell-derived tissues. Mechanisms of endothelin action during neural crest cell maturation have been deciphered using a variety of in vivo and in vitro approaches, with these studies elucidating the basis of human syndromes involving developmental differences resulting from altered endothelin signaling. In this Review, we describe the endothelin pathway and its functions during the development of neural crest-derived tissues. We also summarize how dysregulated endothelin signaling causes developmental differences and how this knowledge may lead to potential treatments for individuals with gene variants in the endothelin pathway.

Ret deficiency decreases neural crest progenitor proliferation and restricts fate potential during enteric nervous system development.

The receptor tyrosine kinase RET plays a critical role in the fate specification of enteric neural crest-derived cells (ENCDCs) during enteric nervous system (ENS) development. RET loss of function (LoF) is associated with Hirschsprung disease (HSCR), which is marked by aganglionosis of the gastrointestinal (GI) tract. Although the major phenotypic consequences and the underlying transcriptional changes from Ret LoF in the developing ENS have been described, cell type- and state-specific effects are unknown. We performed single-cell RNA sequencing on an enriched population of ENCDCs from the developing GI tract of Ret null heterozygous and homozygous mice at embryonic day (E)12.5 and E14.5. We demonstrate four significant findings: 1) Ret-expressing ENCDCs are a heterogeneous population comprising ENS progenitors as well as glial- and neuronal-committed cells; 2) neurons committed to a predominantly inhibitory motor neuron developmental trajectory are not produced under Ret LoF, leaving behind a mostly excitatory motor neuron developmental program; 3) expression patterns of HSCR-associated and Ret gene regulatory network genes are impacted by Ret LoF; and 4) Ret deficiency leads to precocious differentiation and reduction in the number of proliferating ENS precursors. Our results support a model in which Ret contributes to multiple distinct cellular phenotypes during development of the ENS, including the specification of inhibitory neuron subtypes, cell cycle dynamics of ENS progenitors, and the developmental timing of neuronal and glial commitment.

Three-Dimensional Imaging of the Enteric Nervous System in Human Pediatric Colon Reveals New Features of Hirschsprung's Disease.

BACKGROUND & AIMS: Hirschsprung's disease is defined by the absence of the enteric nervous system (ENS) from the distal bowel. Primary treatment is "pull-through" surgery to remove bowel that lacks ENS, with reanastomosis of "normal" bowel near the anal verge. Problems after pull-through are common, and some may be due to retained hypoganglionic bowel (ie, low ENS density). Testing this hypothesis has been difficult because counting enteric neurons in tissue sections is unreliable, even for experts. Tissue clearing and 3-dimensional imaging provide better data about ENS structure than sectioning. METHODS: Regions from 11 human colons and 1 ileal specimen resected during Hirschsprung's disease pull-through surgery were cleared, stained with antibodies to visualize the ENS, and imaged by confocal microscopy. Control distal colon from people with no known bowel problems were similarly cleared, stained, and imaged. RESULTS: Quantitative analyses of human colon, ranging from 3 days to 60 years old, suggest age-dependent changes in the myenteric plexus area, ENS ganglion area, percentage of myenteric plexus occupied by ganglia, neurons/mm2, and neuron Feret's diameter. Neuron counting using 3-dimensional images was highly reproducible. High ENS density in neonatal colon allowed reliable neuron counts using 500-µm2 × 500-µm2 regions (36-fold smaller than in adults). Hirschsprung's samples varied 8-fold in proximal margin enteric neuron density and had diverse ENS architecture in resected bowel. CONCLUSIONS: Tissue clearing and 3-dimensional imaging provide more reliable information about ENS structure than tissue sections. ENS structure changes during childhood. Three-dimensional ENS anatomy may provide new insight into human bowel motility disorders, including Hirschsprung's disease.

Sacral Neural Crest-Independent Origin of the Enteric Nervous System in Mouse.

BACKGROUND & AIMS: The enteric nervous system (ENS), the gut's intrinsic nervous system critical for gastrointestinal function and gut-brain communication, is believed to mainly originate from vagal neural crest cells (vNCCs) and partially from sacral NCCs (sNCCs). Resolving the exact origins of the ENS is critical for understanding congenital ENS diseases but has been confounded by the inability to distinguish between both NCC populations in situ. Here, we aimed to resolve the exact origins of the mammalian ENS. METHODS: We genetically engineered mouse embryos facilitating comparative lineage-tracing of either all (pan-) NCCs including vNCCs or caudal trunk and sNCCs (s/tNCCs) excluding vNCCs. This was combined with dual-lineage tracing and 3-dimensional reconstruction of pelvic plexus and hindgut to precisely pinpoint sNCC and vNCC contributions. We further used coculture assays to determine the specificity of cell migration from different neural tissues into the hindgut. RESULTS: Both pan-NCCs and s/tNCCs contributed to established NCC derivatives but only pan-NCCs contributed to the ENS. Dual-lineage tracing combined with 3-dimensional reconstruction revealed that s/tNCCs settle in complex patterns in pelvic plexus and hindgut-surrounding tissues, explaining previous confusion regarding their contributions. Coculture experiments revealed unspecific cell migration from autonomic, sensory, and neural tube explants into the hindgut. Lineage tracing of ENS precursors lastly provided complimentary evidence for an exclusive vNCC origin of the murine ENS. CONCLUSIONS: sNCCs do not contribute to the murine ENS, suggesting that the mammalian ENS exclusively originates from vNCCs. These results have immediate implications for comprehending (and devising treatments for) congenital ENS disorders, including Hirschsprung's disease.

Human enteric nervous system progenitor transplantation improves functional responses in Hirschsprung disease patient-derived tissue.

OBJECTIVE: Hirschsprung disease (HSCR) is a severe congenital disorder affecting 1:5000 live births. HSCR results from the failure of enteric nervous system (ENS) progenitors to fully colonise the gastrointestinal tract during embryonic development. This leads to aganglionosis in the distal bowel, resulting in disrupted motor activity and impaired peristalsis. Currently, the only viable treatment option is surgical resection of the aganglionic bowel. However, patients frequently suffer debilitating, lifelong symptoms, with multiple surgical procedures often necessary. Hence, alternative treatment options are crucial. An attractive strategy involves the transplantation of ENS progenitors generated from human pluripotent stem cells (hPSCs). DESIGN: ENS progenitors were generated from hPSCs using an accelerated protocol and characterised, in detail, through a combination of single-cell RNA sequencing, protein expression analysis and calcium imaging. We tested ENS progenitors' capacity to integrate and affect functional responses in HSCR colon, after ex vivo transplantation to organotypically cultured patient-derived colonic tissue, using organ bath contractility. RESULTS: We found that our protocol consistently gives rise to high yields of a cell population exhibiting transcriptional and functional hallmarks of early ENS progenitors. Following transplantation, hPSC-derived ENS progenitors integrate, migrate and form neurons/glia within explanted human HSCR colon samples. Importantly, the transplanted HSCR tissue displayed significantly increased basal contractile activity and increased responses to electrical stimulation compared with control tissue. CONCLUSION: Our findings demonstrate, for the first time, the potential of hPSC-derived ENS progenitors to repopulate and increase functional responses in human HSCR patient colonic tissue.

H3K36 methyltransferase SMYD2 affects cell proliferation and migration in Hirschsprung's disease by regulating METTL3.

The pathogenesis of Hirschsprung's disease (HSCR) is complex. Recently, it has been found that histone modifications can alter genetic susceptibility and play important roles in the proliferation, differentiation and migration of neural crest cells. H3K36 methylation plays a significant role in gene transcriptional activation and expression, but its pathogenic mechanism in HSCR has not yet been studied. This study aimed to elucidate its role and molecular mechanism in HSCR. Western blot analysis, immunohistochemistry (IHC) and reverse transcription-quantitative PCR (RT‒qPCR) were used to investigate H3K36 methylation and methyltransferase levels in dilated and stenotic colon tissue sections from children with. We confirm that SMYD2 is the primary cause of differential H3K36 methylation and influences cell proliferation and migration in HSCR. Subsequently, quantitative detection of m6A RNA methylation revealed that SMYD2 can alter m6A methylation levels. Western blot analysis, RT-qPCR, co-immunoprecipitation (co-IP), and immunofluorescence colocalization were utilized to confirm that SMYD2 can regulate METTL3 expression and affect m6A methylation, affecting cell proliferation and migration. These results confirm that the H3K36 methyltransferase SMYD2 can affect cell proliferation and migration in Hirschsprung's disease by regulating METTL3. Our study suggested that H3K36 methylation plays an important role in HSCR, confirming that the methyltransferase SMYD2 can affect m6A methylation levels and intestinal nervous system development by regulating METTL3 expression.

Avian ceca are indispensable for hindgut enteric nervous system development.

The enteric nervous system (ENS), which is derived from enteric neural crest cells (ENCCs), represents the neuronal innervation of the intestine. Compromised ENCC migration can lead to Hirschsprung disease, which is characterized by an aganglionic distal bowel. During the craniocaudal migration of ENCCs along the gut, we find that their proliferation is greatest as the ENCC wavefront passes through the ceca, a pair of pouches at the midgut-hindgut junction in avian intestine. Removal of the ceca leads to hindgut aganglionosis, suggesting that they are required for ENS development. Comparative transcriptome profiling of the cecal buds compared with the interceca region shows that the non-canonical Wnt signaling pathway is preferentially expressed within the ceca. Specifically, WNT11 is highly expressed, as confirmed by RNA in situ hybridization, leading us to hypothesize that cecal expression of WNT11 is important for ENCC colonization of the hindgut. Organ cultures using embryonic day 6 avian intestine show that WNT11 inhibits enteric neuronal differentiation. These results reveal an essential role for the ceca during hindgut ENS formation and highlight an important function for non-canonical Wnt signaling in regulating ENCC differentiation.

ERBB3 deficiency causes a multisystemic syndrome in human patient and zebrafish.

The Erb-B2 receptor tyrosine kinase 3 (ERBB3) gene was first identified as a cause of lethal congenital contracture syndrome (OMIM 607598), while a recent study reported six additional patients carrying ERBB3 variants which exhibited distinct clinical features with evident intestinal dysmotility (OMIM 243180). The potential connection between these phenotypes remains unknown, and the ERBB3-related phenotype spectrum needs to be better characterized. Here, we described a patient presenting with a multisystemic syndrome including skip segment Hirschsprung disease, bilateral clubfoot deformity, and cardiac defect. Trio-whole exome sequencing revealed a novel compound heterozygous variant (c.1914-7C>G; c.2942_2945del) in the patient's ERBB3 gene. RT-PCR and in vitro minigene analysis demonstrated that variant c.1914-7C>G caused aberrant mRNA splicing. Both variants resulted in premature termination codon and complete loss of ERBB3 function. erbb3b knockdown in zebrafish simultaneously caused a reduction in enteric neurons in the distal intestine, craniofacial cartilage defects, and micrognathia, which phenotypically mimics ERBB3-related intestinal dysmotility and some features of lethal congenital contracture syndrome in human patients. These findings provide further patient and animal evidence supporting that ERBB3 deficiency causes a complex syndrome involving multiple systems with phenotypic variability among distinct individuals.

Further description of two individuals with de novo p.(Glu127Lys) missense variant in the ASCL1 gene.

Achaete-Scute Family basic-helix-loop-helix (bHLH) Transcription Factor 1 (ASCL1) is a proneural transcription factor involved in neuron development in the central and peripheral nervous system. While initially suspected to contribute to congenital central hypoventilation syndrome-1 (CCHS) with or without Hirschsprung disease (HSCR) in three individuals, its implication was ruled out by the presence, in one of the individuals, of a Paired-like homeobox 2B (PHOX2B) heterozygous polyalanine expansion variant, known to cause CCHS. We report two additional unrelated individuals sharing the same sporadic ASCL1 p.(Glu127Lys) missense variant in the bHLH domain and a common phenotype with short-segment HSCR, signs of dysautonomia, and developmental delay. One has also mild CCHS without polyalanine expansion in PHOX2B, compatible with the diagnosis of Haddad syndrome. Furthermore, missense variants with homologous position in the same bHLH domain in other genes are known to cause human diseases. The description of additional individuals carrying the same variant and similar phenotype, as well as targeted functional studies, would be interesting to further evaluate the role of ASCL1 in neurocristopathies.

Pull-Through for Hirschsprung's Disease: Insights for Limited-Resource Settings From Mbarara.

INTRODUCTION: In many resource-limited settings, patients with Hirschsprung's Disease (HD) undergo initial diverting colostomy, followed by pull-through, and finally, colostomy closure. This approach allows for decompression of dilated and thickened bowel and improved patient nutritional status. However, this three-stage approach prolongs treatment duration, with significant stoma morbidity, costs, and impact on quality of life. Our aim was to determine whether pull-through for HD can safely be performed with simultaneous stoma closure, reducing treatment approach from three to two stages. METHODS: Children with HD and diverting colostomy were prospectively followed as they underwent pull-through with simultaneous stoma closure. Their in-hospital course and 3-mo outpatient course were assessed for postoperative complications. Patients with total colonic HD, redo pull-through, and residual dilated colon were excluded from the study. RESULTS: Of the 20 children, 17 were male (n = 17, 85%). All patients had rectosigmoid HD. The median weight, age at colostomy formation, and age at pull-through were 11.05 kg (interquartile range [IQR] 10-12.75), 0.9 y (IQR 0.25-2.8), and 2.08 y (IQR 1.28-2.75), respectively. Mean duration with colostomy before pull-through was 1.1 y (standard deviation 1.51). Median hospital length of stay was 6 d (IQR 5-7). Early complications included anastomotic leak (n = 1), perianal skin excoriation (n = 2), surgical site skin infection (n = 3), and fascial dehiscence (n = 1). Longer-term complications included stricture (n = 1, 5%) and enterocolitis (n = 2, 10%). CONCLUSIONS: In this small case series, we have demonstrated that pull-through with simultaneous stoma closure can be safely performed in resource-constrained settings. Further studies are needed to understand the quality of life and economic impact of this change in management for HD patients.

Statewide Hospital Admissions for Adult Survivors of Infant Surgical Diseases Over a 10-Year Period.

INTRODUCTION: The number of patients with congenital disease living to adulthood continues to grow. Often undergoing surgical correction in infancy, they continue to require lifelong care. Their numbers are largely unknown. We sought to evaluate hospital admissions of adult patients with esophageal atresia with tracheoesophageal fistula (EA/TEF), congenital diaphragmatic hernia (CDH), and Hirschsprung disease (HD). METHODS: The Florida Agency for Healthcare Administration inpatient database was merged with the Distressed Communities Index and Centers for Medicare and Medicaid Services Hospital and Physician Compare datasets. The dataset was queried for adult patients (≥18 y, born after 1970) with EA/TEF, CDH, and HD in their problem list from 2010 to 2020. Patient demographics, hospitalization characteristics, and discharge information were obtained. RESULTS: In total, 1140 admissions were identified (266 EA/TEF, 135 CDH, 739 HD). Patients were mostly female (53%), had a mean age of 31.6 y, and often admitted to an adult internist in a general hospital under emergency. Principal diagnoses and procedures (when performed) varied with diagnosis and age at admission. EA patients were admitted with dysphagia and foregut symptoms and often underwent upper endoscopy with dilation. CDH patients were often admitted for diaphragmatic hernias and underwent adult diaphragm repair. Hirschsprung patients were often admitted for intestinal obstructive issues and frequently underwent colonoscopy but trended toward operative intervention with increasing age. CONCLUSIONS: Adults with congenital disease continue to require hospital admission and invasive procedures. As age increases, diagnoses and performed procedures for each diagnoses evolve. These data could guide the formulation of multispecialty disease-specific follow-up programs for these patients.

Treatment of Persistent Soiling in Hirschsprung Disease With Antegrade Continence Enemas.

INTRODUCTION: Patients with Hirschsprung disease (HD) can experience soiling after their pull-through. We evaluated the use of antegrade continence enema (ACE) for this patient population and investigated the timing and factors associated with getting the patient clean. METHODS: We performed a single-institution retrospective review (from January 2020 to January 2023) of patients with HD and prior pull-through who had persistent soiling, failed laxative treatment or rectal enemas, and were treated with antegrade enemas. The primary outcome was time to become "clean of stool" which was defined as at least one bowel movement per day, no more than one stool accident per week, and no significant stool burden radiographically. Kaplan-Meier survival analysis was performed, and univariate cox proportional hazard regression was used to assess factors associated with time to continence. RESULTS: Thirty patients who met the criteria underwent ACE creation at a median age of 6.5 y (interquartile range 5.3-9.8) with a median follow-up time of 11.5 mo (interquartile range 5.6-16.5). Most patients became clean by 4 mo (13 of 20, 65%) with similar results at 1-y follow-up (16 of 21, 76%). The median time to becoming clean was 4.3 mo (95% confidence interval: 1.7-15.0. Patients with hypermotility were more likely to continue to soil at 1 y (80% versus 13%, P = 0.01). There were no additional factors significantly associated with time to cleanliness. CONCLUSIONS: ACE is a useful modality for HD patients with soiling. Most became clean of stool in 4 mo. The presence of hypermotility was associated with a higher incidence of persistent soiling at 1 y.

Clinical relevance of inflammation on rectal biopsy for Hirschsprung disease: An outcomes analysis.

OBJECTIVES: Inflammation on diagnostic rectal biopsy for children with suspected Hirschsprung disease (HSCR) is reported on pathology, and its significance is unknown. We describe the management and outcomes of a cohort with inflammation on rectal biopsy compared to those without. Specifically, to address the hypothesis that inflammation on diagnostic biopsy is associated with increased complication rates irrespective of intervention type and timing. METHODS: A single institution retrospective review of children with HSCR who underwent biopsy and endorectal pull-through (ERPT) from 2010 to 2020 was performed. The primary outcome was overall complications at 30-days following ERPT. Secondary outcomes included timing and type of operative intervention as well as postoperative enterocolitis diagnosed within 6-months of ERPT. RESULTS: Forty-nine children were identified; inflammation was present on diagnostic biopsy for 17 children. Those with inflammation were more likely to have clinical evidence of enterocolitis at the time of biopsy (p = 0.001) and were more likely to undergo leveling colostomy before ERPT (p = 0.01). Children with inflammation had a higher anastomotic leak rate (p = 0.04). Subgroup analysis of patients with inflammation undergoing primary ERPT versus leveling colostomy demonstrated no significant difference in outcomes following definitive ERPT. CONCLUSIONS: Our study suggests inflammation on diagnostic rectal biopsy for HSCR is associated with increased anastomotic leak rates. While additional prospective studies are indicated, attention to methods of mitigating inflammation and confirming its resolution before definitive pull-through may be of benefit for improving clinical outcomes in patients found with inflammation on diagnostic rectal biopsy.

Early intervention in Hirschsprung's disease: effects on enterocolitis and surgical outcomes.

BACKGROUND: The timing of surgical intervention for Hirschsprung's disease (HSCR) has been a topic of continued discussion. The objective of this study was to evaluate the significance of age at surgery in the management of HSCR by conducting a comparative analysis of the correlation between surgical age and midterm outcomes. METHODS: We conducted a retrospective analysis of children with HSCR who underwent one-stage laparoscopic assisted pull-through surgery with modified Swenson technology at our hospital between 2015 and 2019. The study population was stratified into two groups based on surgical age: patients who underwent surgery within a period of less than 3 months and those who underwent surgery between 3 and 12 months. The basic conditions, complications at 3-7 years after surgery, anal function (Rintala scale) and quality of life (PedsQLTM4.0) were compared between the groups. RESULTS: A total of 235 children (196 males and 39 females) were included in the study. No statistically significant differences in postoperative bowel function (P = 0.968) or quality of life (P = 0.32) were found between the two groups. However, there was a significant reduction in the incidence of Hirschsprung-associated enterocolitis (HAEC) among individuals under the age of three months prior to undergoing surgical intervention (69.1%) compared to the incidence observed postsurgery (30.9%). This difference was statistically significant (P < 0.001). CONCLUSION: In the current study, the age at which surgery was performed did not exhibit a discernible inclination towards influencing mid-term anal function or quality of life. Early surgical intervention can effectively diminish the occurrence of HAEC, minimize the extent of bowel resection, and expedite the duration of the surgical procedure.

Aberrant SOX10 and RET expressions in patients with Hirschsprung disease.

BACKGROUND: HSCR is a complex genetic disorder characterized by the absence of ganglion cells in the intestine, leading to a functional obstruction. It is due to a disruption of complex signaling pathways within the gene regulatory network (GRN) during the development of the enteric nervous system (ENS), including SRY-Box Transcription Factor 10 (SOX10) and REarranged during Transfection (RET). This study evaluated the expressions of SOX10 and RET in HSCR patients in Indonesia. METHODS: Total RNA of 19 HSCR ganglionic and aganglionic colons and 16 control colons were analyzed using quantitative real-time polymerase chain reaction for SOX10 and RET with GAPDH as the reference gene. Livak's method (2-ΔΔCT) was used to determine the expression levels of SOX10 and RET. RESULTS: Most patients were males (68.4%), in the short aganglionosis segment (78.9%), and had undergone transanal endorectal pull-through (36.6%). There were significant upregulated SOX10 expressions in both ganglionic (2.84-fold) and aganglionic (3.72-fold) colon of HSCR patients compared to controls' colon (ΔCT 5.21 ± 2.04 vs. 6.71 ± 1.90; p = 0.032; and ΔCT 4.82 ± 1.59 vs. 6.71 ± 1.90; p = 0.003; respectively). Interestingly, the RET expressions were significantly downregulated in both ganglionic (11.71-fold) and aganglionic (29.96-fold) colon of HSCR patients compared to controls' colon (ΔCT 12.54 ± 2.21 vs. 8.99 ± 3.13; p = 0.0004; and ΔCT 13.90 ± 2.64 vs. 8.99 ± 3.13; p = 0.0001; respectively). CONCLUSIONS: Our study shows aberrant SOX10 and RET expressions in HSCR patients, implying the critical role of SOX10 and RET in the pathogenesis of HSCR, particularly in the Indonesian population. Our study further confirms the involvement of SOX10-RET within the GNR during the ENS development.

Extended total colonic aganglionosis and total intestinal aganglionosis: Challenging enemies.

AIM: Extended total colonic aganglionosis (ETCA) represents uncommon forms of Hirschsprung disease (HD), with aganglionosis extending into the proximal small bowel. ETCA management is challenging and associated with poor outcomes and high mortality. This study compares management and outcomes of ETCA to more common HD forms. METHODS: A retrospective cohort of HD patients (2012-2023) from two institutions. Three HD forms were compared: short-segment HD (SSHD, n = 19), long-segment HD or total colonic aganglionosis (LS/TCA, n = 9) and ETCA (n = 7). RESULTS: Normally innervated segments in ETCA patients ranged 0-70 cm. Median times to first surgery were; ETCA = 3 days versus TCA = 21 days (p = 0.017) and SSHD = 95 days (p < 0.001), respectively. Median number of surgeries were; ETCA = 4, versus TCA = 2 (p = 0.17) and SSHD = 1 (p = 0.002), respectively. All the patients underwent a definitive pull-through procedure, except four ETCA patients with a permanent jejunostomy and residual aganglionic segment of 57-130 cm. ETCA patients had 92% lower odds of enterocolitis (14%) compared to TCA patients (67%, p = 0.054), and comparable odds to SSHD patients (16%, p = 0.92). ETCA mortality was 14%. CONCLUSION: Extended total colonic aganglionosis patients require earlier and multiple interventions. Leaving an aganglionic segment may be advantageous, without increasing risk for enterocolitis. Tailored surgical treatment and rehabilitation programmes may prevent mortality and need for transplantation.

miR-146b-5p Regulates the Enteric Nervous System Development in Hirschsprung Disease via Targeting RET Pathway.

The objective of the study is to investigate how miR-146b-5p might contribute to the etiology of HSCR. The study investigated the expression levels of miRNA, mRNA, and proteins in colon tissues obtained from the HSCR and control groups. The role of miR-146b-5p in cell proliferation and migration was studied in vitro. The interaction between miR-146b-5p and RET was validated through a dual-luciferase reporter experiment. To assess the impact of miR-146b-5p on the development of the enteric nervous system, zebrafish embryos were micro-injected with either miR-146b-5p mimics or negative control, followed by subsequent evaluation. Compared to the control group, miR-146b-5p expression levels in the spastic region of HSCR were significantly increased. In vitro, miR-146b-5p prevented cell migration and proliferation by targeting RET pathway. In zebrafish, miR-146b-5p negatively regulates the migration of neural crest cells through a reduction in RET expression. Overexpression of miR-146b-5p hinders the development of mature neurons by decreasing RET expression. Additionally, the aberrant phenotypes induced by miR-146b-5p were partially ameliorated when RET mRNA was co-injected. By targeting RET in HSCR patients, aberrant expression of miR-146b-5p may play a unique role in the etiology of the disease and be involved in enteric nervous system development.