Resolving Resident Colonic Muscularis Macrophage Diversity and Plasticity During Colitis.

BACKGROUND: Immune cell populations in the intestinal muscularis propria during colitis are poorly resolved. Maintaining homeostasis in this niche is critical, highlighted by the poorer prognosis of inflammatory bowel disease associated with muscularis propria inflammation. METHODS: This study utilizes single-cell RNA sequencing to survey the immune cell populations within the muscularis propria of normal colon and dextran sodium sulfate-induced colitis. Findings are validated by immunohistochemistry, flow cytometry and cell-lineage tracing in vivo, and in vitro assays with muscularis macrophages (MMφ). RESULTS: In naïve conditions, transcriptional duality is observed in MMφs with 2 major subpopulations: conventional resident Cx3cr1+ MMφs and Lyve1+ MMφs. The Lyve1+ population is phagocytic and expresses several known MMφ markers in mouse and human, confirming their identity as a bona fide MMφ subset. Single-cell transcriptomics indicate that resident MMφs are retained during colitis and exhibit plasticity toward an inflammatory profile. Lyve1+ MMφs, which express anti-inflammatory marker CD163, are absent during colitis, as confirmed by flow cytometry. In contrast, lineage tracing finds that resident Cx3cr1+ MMφs remain during colitis and are not completely replaced by the inflammatory infiltrating monocytes. In vitro studies provide biological evidence of the plasticity of resident Cx3cr1+ MMφs in response to lipopolysaccharide (LPS), mirroring transcriptional observations in vivo of their inflammatory plasticity. Potential markers for colitic MMφs, validated in animal models and in individuals with ulcerative colitis, are identified. CONCLUSIONS: Our findings contribute to the understanding of the immune system in the muscularis propria niche during colitis by resolving the heterogeneity and origins of colitic MMφs.

Involvement of the muscularis propria accompanies a poorer prognosis in IBD. This study characterizes muscularis macrophage subpopulations during colitis, highlighting the loss of anti-inflammatory LYVE-1+ macrophages and inflammatory plasticity in resident CX3CR1+ macrophages, providing insights into prognostic and therapeutic targets.

Mature enteric neurons have the capacity to reinnervate the intestine with glial cells as their guide.

Here, we establish that plasticity exists within the postnatal enteric nervous system by demonstrating the reinnervation potential of post-mitotic enteric neurons (ENs). Employing BAF53b-Cre mice for selective neuronal tracing, the reinnervation capabilities of mature postnatal ENs are shown across multiple model systems. Isolated ENs regenerate neurites in vitro, with neurite complexity and direction influenced by contact with enteric glial cells (EGCs). Nerve fibers from transplanted ENs exclusively interface and travel along EGCs within the muscularis propria. Resident EGCs persist after Cre-dependent ablation of ENs and govern the architecture of the myenteric plexus for reinnervating ENs, as shown by nerve fiber projection tracing. Transplantation and optogenetic experiments in vivo highlight the rapid reinnervation potential of post-mitotic neurons, leading to restored gut muscle contractile activity within 2 weeks. These studies illustrate the structural and functional reinnervation capacity of post-mitotic ENs and the critical role of EGCs in guiding and patterning their trajectories.

Enteric neural stem cell transplant restores gut motility in mice with Hirschsprung disease.

The goal of this study was to determine if transplantation of enteric neural stem cells (ENSCs) can rescue the enteric nervous system, restore gut motility, reduce colonic inflammation, and improve survival in the Ednrb-KO mouse model of Hirschsprung disease (HSCR). ENSCs were isolated from mouse intestine, expanded to form neurospheres, and microinjected into the colons of recipient Ednrb-KO mice. Transplanted ENSCs were identified in recipient colons as cell clusters in "neo-ganglia." Immunohistochemical evaluation demonstrated extensive cell migration away from the sites of cell delivery and across the muscle layers. Electrical field stimulation and optogenetics showed significantly enhanced contractile activity of aganglionic colonic smooth muscle following ENSC transplantation and confirmed functional neuromuscular integration of the transplanted ENSC-derived neurons. ENSC injection also partially restored the colonic migrating motor complex. Histological examination revealed a significant reduction in inflammation in ENSC-transplanted aganglionic recipient colon compared with that of sham-operated mice. Interestingly, mice that received cell transplant also had prolonged survival compared with controls. This study demonstrates that ENSC transplantation can improve outcomes in HSCR by restoring gut motility and reducing the severity of Hirschsprung-associated enterocolitis, the leading cause of death in human HSCR.

Autologous cell transplantation for treatment of colorectal aganglionosis in mice.

Neurointestinal diseases cause significant morbidity and effective treatments are lacking. This study aimes to test the feasibility of transplanting autologous enteric neural stem cells (ENSCs) to rescue the enteric nervous system (ENS) in a model of colonic aganglionosis. ENSCs are isolated from a segment of small intestine from Wnt1::Cre;R26iDTR mice in which focal colonic aganglionosis is simultaneously created by diphtheria toxin injection. Autologous ENSCs are isolated, expanded, labeled with lentiviral-GFP, and transplanted into the aganglionic segment in vivo. ENSCs differentiate into neurons and glia, cluster to form neo-ganglia, and restore colonic contractile activity as shown by electrical field stimulation and optogenetics. Using a non-lethal model of colonic aganglionosis, our results demonstrate the potential of autologous ENSC therapy to improve functional outcomes in neurointestinal disease, laying the groundwork for clinical application of this regenerative cell-based approach.

Optogenetic Activation of Cholinergic Enteric Neurons Reduces Inflammation in Experimental Colitis.

BACKGROUND & AIMS: Intestinal inflammation is associated with loss of enteric cholinergic neurons. Given the systemic anti-inflammatory role of cholinergic innervation, we hypothesized that enteric cholinergic neurons similarly possess anti-inflammatory properties and may represent a novel target to treat inflammatory bowel disease. METHODS: Mice were fed 2.5% dextran sodium sulfate (DSS) for 7 days to induce colitis. Cholinergic enteric neurons, which express choline acetyltransferase (ChAT), were focally ablated in the midcolon of ChAT::Cre;R26-iDTR mice by local injection of diphtheria toxin before colitis induction. Activation of enteric cholinergic neurons was achieved using ChAT::Cre;R26-ChR2 mice, in which ChAT+ neurons express channelrhodopsin-2, with daily blue light stimulation delivered via an intracolonic probe during the 7 days of DSS treatment. Colitis severity, ENS structure, and smooth muscle contractility were assessed by histology, immunohistochemistry, quantitative polymerase chain reaction, organ bath, and electromyography. In vitro studies assessed the anti-inflammatory role of enteric cholinergic neurons on cultured muscularis macrophages. RESULTS: Ablation of ChAT+ neurons in DSS-treated mice exacerbated colitis, as measured by weight loss, colon shortening, histologic inflammation, and CD45+ cell infiltration, and led to colonic dysmotility. Conversely, optogenetic activation of enteric cholinergic neurons improved colitis, preserved smooth muscle contractility, protected against loss of cholinergic neurons, and reduced proinflammatory cytokine production. Both acetylcholine and optogenetic cholinergic neuron activation in vitro reduced proinflammatory cytokine expression in lipopolysaccharide-stimulated muscularis macrophages. CONCLUSIONS: These findings show that enteric cholinergic neurons have an anti-inflammatory role in the colon and should be explored as a potential inflammatory bowel disease treatment.

Bone Marrow Stem Cells Derived from Nerves Have Neurogenic Properties and Potential Utility for Regenerative Therapy.

Neurons and glia of the peripheral nervous system are derived from progenitor cell populations, originating from embryonic neural crest. The neural crest and vasculature are intimately associated during embryonic development and in the mature central nervous system, in which they form a neurovascular unit comprised of neurons, glia, pericytes, and vascular endothelial cells that play important roles in health and disease. Our group and others have previously reported that postnatal populations of stem cells originating from glia or Schwann cells possess neural stem cell qualities, including rapid proliferation and differentiation into mature glia and neurons. Bone marrow receives sensory and sympathetic innervation from the peripheral nervous system and is known to contain myelinating and unmyelinating Schwann cells. Herein, we describe a population of neural crest-derived Schwann cells residing in a neurovascular niche of bone marrow in association with nerve fibers. These Schwann cells can be isolated and expanded. They demonstrate plasticity in vitro, generating neural stem cells that exhibit neurogenic potential and form neural networks within the enteric nervous system in vivo following transplantation to the intestine. These cells represent a novel source of autologous neural stem cells for the treatment of neurointestinal disorders.

Oxaliplatin-Induced Damage to the Gastric Innervation: Role in Nausea and Vomiting.

Nausea and vomiting are common gastrointestinal side effects of oxaliplatin chemotherapy used for the treatment of colorectal cancer. However, the mechanism underlying oxaliplatin-induced nausea and vomiting is unknown. The stomach is involved in the emetic reflex but no study investigated the effects of oxaliplatin treatment on the stomach. In this study, the in vivo effects of oxaliplatin treatment on eating behaviour, stomach content, intrinsic gastric neuronal population, extrinsic innervation to the stomach, levels of mucosal serotonin (5-hydroxytryptamine, 5-HT), and parasympathetic vagal efferent nerve activity were analysed. Chronic systemic oxaliplatin treatment in mice resulted in pica, indicated by increased kaolin consumption and a reduction in body weight. Oxaliplatin treatment significantly increased the stomach weight and content. The total number of myenteric and nitric oxide synthase-immunoreactive neurons as well as the density of sympathetic, parasympathetic, and sensory fibres in the stomach were decreased significantly with oxaliplatin treatment. Oxaliplatin treatment significantly increased the levels in mucosal 5-HT and the number of enterochromaffin-like cells. Chronic oxaliplatin treatment also caused a significant increase in the vagal efferent nerve activity. The findings of this study indicate that oxaliplatin exposure has adverse effects on multiple components of gastric innervation, which could be responsible for pica and gastric dysmotility.

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.

Schwann Cells in the Aganglionic Colon of Hirschsprung Disease Can Generate Neurons for Regenerative Therapy.

Cell therapy offers the potential to replace the missing enteric nervous system (ENS) in patients with Hirschsprung disease (HSCR) and to restore gut function. The Schwann cell (SC) lineage has been shown to generate enteric neurons pre- and post-natally. Here, we aimed to isolate SCs from the aganglionic segment of HSCR and to determine their potential to restore motility in the aganglionic colon. Proteolipid protein 1 (PLP1) expressing SCs were isolated from the extrinsic nerve fibers present in the aganglionic segment of postnatal mice and patients with HSCR. Following 7-10 days of in vitro expansion, HSCR-derived SCs were transplanted into the aganglionic mouse colon ex vivo and in vivo. Successful engraftment and neuronal differentiation were confirmed immunohistochemically and calcium activity of transplanted cells was demonstrated by live cell imaging. Organ bath studies revealed the restoration of motor function in the recipient aganglionic smooth muscle. These results show that SCs isolated from the aganglionic segment of HSCR mouse can generate functional neurons within the aganglionic gut environment and restore the neuromuscular activity of recipient mouse colon. We conclude that HSCR-derived SCs represent a potential autologous source of neural progenitor cells for regenerative therapy in HSCR.

Schwann cells in the subcutaneous adipose tissue have neurogenic potential and can be used for regenerative therapies.

Stem cell therapies for nervous system disorders are hindered by a lack of accessible autologous sources of neural stem cells (NSCs). In this study, neural crest-derived Schwann cells are found to populate nerve fiber bundles (NFBs) residing in mouse and human subcutaneous adipose tissue (SAT). NFBs containing Schwann cells were harvested from mouse and human SAT and cultured in vitro. During in vitro culture, SAT-derived Schwann cells remodeled NFBs to form neurospheres and exhibited neurogenic differentiation potential. Transcriptional profiling determined that the acquisition of these NSC properties can be attributed to dedifferentiation processes in cultured Schwann cells. The emerging population of cells were termed SAT-NSCs because of their considerably distinct gene expression profile, cell markers, and differentiation potential compared to endogenous Schwann cells existing in vivo. SAT-NSCs successfully engrafted to the gastrointestinal tract of mice, migrated longitudinally and circumferentially within the muscularis, differentiated into neurons and glia, and exhibited neurochemical coding and calcium signaling properties consistent with an enteric neuronal phenotype. These cells rescued functional deficits associated with colonic aganglionosis and gastroparesis, indicating their therapeutic potential as a cell therapy for gastrointestinal dysmotility. SAT can be harvested easily and offers unprecedented accessibility for the derivation of autologous NSCs from adult tissues. Evidence from this study indicates that SAT-NSCs are not derived from mesenchymal stem cells and instead originate from Schwann cells within NFBs. Our data describe efficient isolation procedures for mouse and human SAT-NSCs and suggest that these cells have potential for therapeutic applications in gastrointestinal motility disorders.

Divergent Adaptations in Autonomic Nerve Activity and Neuroimmune Signaling Associated With the Severity of Inflammation in Chronic Colitis.

BACKGROUND: The autonomic nervous system (ANS) is thought to play a critical role in the anti-inflammatory reflex pathway in acute colitis via its interaction with the spleen and colon. Inflammation in the intestine is associated with a blunting of vagal signaling and increased sympathetic activity. As a corollary, methods to restore sympatho-vagal balance are being investigated as therapeutic strategies for the treatment of intestinal inflammation. Nevertheless, it is indefinite whether these autonomic signaling adaptations in colitis are detrimental or beneficial to controlling intestinal inflammation. In this study, models of moderate and severe chronic colitis are utilized to resolve the correlations between sympatho-vagal signaling and the severity of intestinal inflammation. METHODS: Spleens and colons were collected from Winnie (moderate colitis), Winnie-Prolapse (severe colitis), and control C57BL/6 mice. Changes to the size and histomorphology of spleens were evaluated. Flow cytometry was used to determine the expression of adrenergic and cholinergic signaling proteins in splenic B and T lymphocytes. The inflammatory profile of the spleen and colon was determined using a RT-PCR gene array. Blood pressure, heart rate, splanchnic sympathetic nerve and vagus nerve activity were recorded. RESULTS: Spleens and colons from Winnie and Winnie-Prolapse mice exhibited gross abnormalities by histopathology. Genes associated with a pro-inflammatory response were upregulated in the colons from Winnie and further augmented in colons from Winnie-Prolapse mice. Conversely, many pro-inflammatory markers were downregulated in the spleens from Winnie-Prolapse mice. Heightened activity of the splanchnic nerve was observed in Winnie but not Winnie-Prolapse mice. Conversely, vagal nerve activity was greater in Winnie-Prolapse mice compared with Winnie mice. Splenic lymphocytes expressing α1 and ß2 adrenoreceptors were reduced, but those expressing α7 nAChR and producing acetylcholine were increased in Winnie and Winnie-Prolapse mice. CONCLUSIONS: Sympathetic activity may correlate with an adaptive mechanism to reduce the severity of chronic colitis. The Winnie and Winnie-Prolapse mouse models of moderate and severe chronic colitis are well suited to examine the pathophysiology of progressive chronic intestinal inflammation.

In this study we use mouse models of moderate and severe colitis to resolve the relationship between autonomic and neuroimmune signaling with inflammation. Increased expression of cholinergic markers on immune cells correlated with an anti-inflammatory profile in the spleen, consistent with activation of the splenic cholinergic anti-inflammatory pathway in mice with spontaneous chronic colitis. However, enhanced sympathetic signaling occurred in mice with a less severe phenotype of colitis, which could represent an adaptive mechanism to mitigate the progression of intestinal inflammation.

Serum Galanin in Children with Autism Spectrum Disorder.

Recent studies have attempted to measure several biomarkers to understand the complex interactions of the anatomic systems that may be involved in autism spectrum disorder (ASD). In CNS, galanin takes part in a variety of pathological and physiological processes. Prior research has indicated it is involved in several neuropsychiatric disorders and has a role in inhibiting the neuronal firing and release of serotonin, norepinephrine, and acetylcholine. To date, serum galanin levels have not been investigated in the context of ASD. This study aimed, therefore, to compare the serum galanin levels of children with ASD and healthy controls and to reveal any association between galanin level and the severity of ASD, as well as other psychological and demographic parameters. Serum galanin levels were measured by radioimmunoassay in 116 children with ASD and 98 healthy children. We observed significantly increased serum concentrations of galanin in children with ASD relative to healthy children. Moreover, children with severe ASD had significantly higher galanin levels than those with less severe disease. We also confirmed significant positive correlations between galanin and psychiatric parameters in children with ASD. For the first time, we suggest a possible correlation between serum galanin and the degree of ASD severity. Increased galanin levels may play a role in the pathogenesis of ASD.

Renal denervation does not affect hypertension or the renin-angiotensin system in a rodent model of juvenile-onset polycystic kidney disease: clinical implications.

We examined the effect of total and afferent renal denervation (RDN) on hypertension and the renin-angiotensin system (RAS) in a rodent model of juvenile-onset polycystic kidney disease (PKD). Lewis Polycystic Kidney (LPK) and control rats received total, afferent or sham RDN by periaxonal application of phenol, capsaicin or normal saline, respectively, and were monitored for 4-weeks. Afferent RDN did not affect systolic blood pressure (SBP) determined by radiotelemetry in either strain (n = 19) while total RDN significantly reduced SBP in Lewis rats 4-weeks post-denervation (total vs. sham, 122 ± 1 vs. 130 ± 2 mmHg, P = 0.002, n = 25). Plasma and kidney renin content determined by radioimmunoassay were significantly lower in LPK vs. Lewis (plasma: 278.2 ± 6.7 vs. 376.5 ± 11.9 ng Ang I/ml/h; kidney: 260.1 ± 6.3 vs. 753.2 ± 37.9 ng Ang I/mg/h, P < 0.001, n = 26). These parameters were not affected by RDN. Intrarenal mRNA expression levels of renin, angiotensinogen, angiotensin-converting enzyme (ACE)2, and angiotensin II receptor type 1a were significantly lower, whereas ACE1 expression was significantly higher in the LPK vs. Lewis (all P < 0.05, n = 26). This pattern of intrarenal RAS expression was not changed by RDN. In conclusion, RDN does not affect hypertension or the RAS in the LPK model and indicates RDN might not be a suitable antihypertensive strategy for individuals with juvenile-onset PKD.

Enteric mesenchymal cells support the growth of postnatal enteric neural stem cells.

Interplay between embryonic enteric neural stem cells (ENSCs) and enteric mesenchymal cells (EMCs) in the embryonic gut is essential for normal development of the enteric nervous system. Disruption of these interactions underlies the pathogenesis of intestinal aganglionosis in Hirschsprung disease (HSCR). ENSC therapy has been proposed as a possible treatment for HSCR, but whether the survival and development of postnatal-derived ENSCs similarly rely on signals from the mesenchymal environment is unknown and has important implications for developing protocols to expand ENSCs for cell transplantation therapy. Enteric neural crest-derived cells (ENCDCs) and EMCs were cultured from the small intestine of Wnt1-Rosa26-tdTomato mice. EMCs promoted the expansion of ENCDCs 9.5-fold by inducing ENSC properties, including expression of Nes, Sox10, Sox2, and Ngfr. EMCs enhanced the neurosphere-forming ability of ENCDCs, and this persisted after withdrawal of the EMCs. These effects were mediated by paracrine factors and several ligands known to support neural stem cells were identified in EMCs. Using the optimized expansion procedures, neurospheres were generated from small intestine of the Ednrb-/- mouse model of HSCR. These ENSCs had similar proliferative and migratory capacity to Ednrb+/+ ENSCs, albeit neurospheres contained fewer neurons. ENSCs derived from Ednrb-/- mice generated functional neurons with similar calcium responses to Ednrb+/+ ENSCs and survived after transplantation into the aganglionic colon of Ednrb-/- recipients. EMCs act as supporting cells to ENSCs postnatally via an array of synergistically acting paracrine signaling factors. These properties can be leveraged to expand autologous ENSCs from patients with HSCR mutations for therapeutic application.

Platinum accumulation in the brain and alteration in the central regulation of cardiovascular and respiratory functions in oxaliplatin-treated rats.

Oxaliplatin is a platinum-based alkylating chemotherapeutic agent used for cancer treatment. Neurotoxicity is one of its major adverse effects that often demands dose limitation. However, the effects of chronic oxaliplatin on the toxicity of the autonomic nervous system regulating cardiorespiratory function and adaptive reflexes are unknown. Male Sprague Dawley rats were treated with intraperitoneal oxaliplatin (3 mg kg-1 per dose) 3 times a week for 14 days. The effects of chronic oxaliplatin treatment on baseline mean arterial pressure (MAP); heart rate (HR); splanchnic sympathetic nerve activity (sSNA); phrenic nerve activity (PNA) and its amplitude (PNamp) and frequency (PNf); and sympathetic reflexes were investigated in anaesthetised, vagotomised and artificially ventilated rats. The same parameters were evaluated after acute oxaliplatin injection, and in the chronic treatment group following a single dose of oxaliplatin. The amount of platinum in the brain was determined with atomic absorption spectrophotometry. Chronic oxaliplatin treatment significantly increased MAP, sSNA and PNf and decreased HR and PNamp, while acute oxaliplatin had no effects. Platinum was accumulated in the brain after chronic oxaliplatin treatment. In the chronic oxaliplatin treatment group, further administration of a single dose of oxaliplatin increased MAP and sSNA. The baroreceptor sensitivity and somatosympathetic reflex were attenuated at rest while the sympathoexcitatory response to hypercapnia was increased in the chronic treatment group. This is the first study to reveal oxaliplatin-induced alterations in the central regulation of cardiovascular and respiratory functions as well as reflexes that may lead to hypertension and breathing disorders which may be mediated via accumulated platinum in the brain.

Assessment of antioxidant traits and protective action of Egyptian acacia pods extracts against paracetamol-induced liver toxicity in rats.

This study investigates the protective effect of Egyptian acacia pod extracts against overdose of paracetamol-induced liver damage. Egyptian acacia green and brown pods were extracted by mixture of ethanol 80%: HCl (6 M) (99:1 v/v). In extracts of green and brown pods, total phenolic content in hydrolyzed ethyl acetate fraction (HEF) at pH 4, was 649.89 and 712.14 mg GAE/g while antioxidant activity was 95.55% and 97.35%, both being the highest than any fraction. HEF (pH 4) in brown pods was analyzed by HPLC, there were 22 phenolic compounds rich in ethyl vanillin about 227 mg/g and 11 flavonoids rich in catechin 48.70 mg/g. A biological experiment was conducted using HEF (pH4) in brown pods against overdose of paracetamol in albino rats induced to hepatotoxicity. Thirty rats were divided into five groups; a control group, a paracetamol group, and the other three received paracetamol plus silymarin or two doses of HEF. Animals were received paracetamol and treated with either silymarin or HEF showed reduced levels of liver (ALT, AST, and ALP) and kidney (urea, creatinine, and uric acid) markers compared with the control group as well as reduction of oxidative stress and increment antioxidant enzyme activity in liver tissue when compared with the paracetamol group. It could be concluded that both HEF and silymarin are considerably high hepatoprotector against paracetamol-induced hepatotoxicity in rats due to their strong antioxidant activity. PRACTICAL APPLICATIONS: Both HEF and silymarin improved liver functions and exerted strong antioxidant activities. This antioxidant activity would have a positive effect against oxidative liver damage caused by parcetamol. Thus, it may be concluded that the liver plasma membranes were protected and the regenerative and reparative capacity of liver by phenolic compound in HEF treatment. The study demonstrated the HEF hepatoprotective activity and recommends using Egyptian acacia pods for treatment of liver disorders.

Polymorphism of interleukin-1ß and interleukin-1 receptor antagonist genes in children with autism spectrum disorders.

In this study, we first investigated interleukin-1 beta (IL-1ß) and IL-1 receptor antagonist (IL-1RA) levels in a cohort of Egyptian children with autism spectrum disorder (ASD) and in healthy controls. Second, we examined the single-nucleotide polymorphisms (SNPs) at positions -31 and - 511 of the IL-1ß gene promoter and IL1RA and assessed the association between IL1B and IL1RA polymorphisms with ASD. We examined IL1ß promoter polymorphism at -511 (IL-1ß-511) and - 31 (IL-1ß-31) and IL1RA gene polymorphism in 80 children with ASD and 60 healthy children. The children with ASD had significantly higher levels of IL-1ß and IL-1RA than the controls. The children with ASD also had significantly higher frequencies of homozygous (CC) and heterozygous (TC) genotype variants of IL-1ß-511, and IL-1RA than the controls. Moreover, the frequency of the IL-1ß-511 allele (C) was higher in the ASD group than in the controls (p = .001). The homozygous and heterozygous variants of IL-1RA allele II were also significantly higher in the ASD group than in the control group. There was no significant association between the IL-1ß-31 genotype and autism classes. However, there were significant differences in the distribution of the IL-1RA heterogeneous genotype and allele II among children with severe autism. The inflammatory role of cytokines has been implicated in a variety of neuropsychiatric pathologies, including autism. Our data show alterations in the IL-1ß system, with abnormally increased serum levels of IL-1ß and IL-1RA in the children with ASD. Further, polymorphisms in the IL-1ß-511 and IL-1RA genotype variants correlated positively with autism severity and behavioral abnormalities. IL-1ß-511 and IL-1RA gene polymorphisms could impact ASD risk and may be used as potential biomarkers of ASD. Variations in the IL-1ß and IL-1RA systems may have a role in the pathophysiology of ASD.

The Onset and Progression of Chronic Colitis Parallels Increased Mucosal Serotonin Release via Enterochromaffin Cell Hyperplasia and Downregulation of the Serotonin Reuptake Transporter.

Background: Serotonin (5-hydroxytryptamine, 5-HT) has been linked with several inflammation-associated intestinal diseases, including ulcerative colitis (UC). The largest pool of 5-HT in the body is in enterochromaffin (EC) cells located throughout the intestinal tract. EC cells are mechanosensitive and detect noxious stimuli, inducing secretion of 5-HT, which plays an important role in enteric reflexes and immunomodulation. In this study, we evaluated intestinal 5-HT levels in the Winnie mouse model of spontaneous chronic colitis, which closely replicates UC. Methods: Real-time electrochemical recordings of 5-HT oxidation currents were obtained from ex vivo preparations of jejunum, ileum, proximal, and distal colon from Winnie (5-25 weeks old) and age matched C57BL/6 mice. EC cells were examined by immunohistochemistry, and the gene expression of tryptophan hydroxylase 1 (5-HT synthesis) and the serotonin reuptake transporter (SERT) were determined by quantitative Real-Time Polymerase Chain Reaction (RT-qPCR). Results: Compression-evoked and basal 5-HT concentrations were elevated in the distal and proximal colon of Winnie mice. EC cell hyperplasia and downregulation of SERT on the transcriptional level were identified as mechanisms underlying increased levels of 5-HT. Increase in mucosal 5-HT release was observed at the onset of disease at 7-14 weeks, confirmed by disease activity scores. Furthermore, increases in 5-HT levels and progression of disease activity correlated linearly with age, but not sex. Conclusions: Our findings in the Winnie mouse model of spontaneous chronic colitis demonstrate for the first time that the onset and progression of chronic UC-like intestinal inflammation is associated with increased 5-HT levels in the colonic mucosa.

Randomized controlled trial of vitamin D supplementation in children with autism spectrum disorder.

BACKGROUND: Autism spectrum disorder (ASD) is a frequent developmental disorder characterized by pervasive deficits in social interaction, impairment in verbal and nonverbal communication, and stereotyped patterns of interests and activities. It has been previously reported that there is vitamin D deficiency in autistic children; however, there is a lack of randomized controlled trials of vitamin D supplementation in ASD children. METHODS: This study is a double-blinded, randomized clinical trial (RCT) that was conducted on 109 children with ASD (85 boys and 24 girls; aged 3-10 years). The aim of this study was to assess the effects of vitamin D supplementation on the core symptoms of autism in children. ASD patients were randomized to receive vitamin D3 or placebo for 4 months. The serum levels of 25-hydroxycholecalciferol (25 (OH)D) were measured at the beginning and at the end of the study. The autism severity and social maturity of the children were assessed by the Childhood Autism Rating Scale (CARS), Aberrant Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and the Autism Treatment Evaluation Checklist (ATEC). TRIAL REGISTRATION NUMBER: UMIN-CTR Study Design: trial number: UMIN000020281. RESULTS: Supplementation of vitamin D was well tolerated by the ASD children. The daily doses used in the therapy group was 300 IU vitamin D3/kg/day, not to exceed 5,000 IU/day. The autism symptoms of the children improved significantly, following 4-month vitamin D3 supplementation, but not in the placebo group. This study demonstrates the efficacy and tolerability of high doses of vitamin D3 in children with ASD. CONCLUSIONS: This study is the first double-blinded RCT proving the efficacy of vitamin D3 in ASD patients. Depending on the parameters measured in the study, oral vitamin D supplementation may safely improve signs and symptoms of ASD and could be recommended for children with ASD. At this stage, this study is a single RCT with a small number of patients, and a great deal of additional wide-scale studies are needed to critically validate the efficacy of vitamin D in ASD.

Frequency of Dendritic Cells and Their Expression of Costimulatory Molecules in Children with Autism Spectrum Disorders.

The aim of our study was to evaluate the frequencies of myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs) in children with ASD. Subjects were 32 children with ASD and 30 healthy children as controls. The numbers of mDCs and pDCs and the expression of CD86 and CD80 on the entire DCs were detected by flow cytometry. ASD children had significantly higher percentages of mDCs and pDCs when compared to controls. We found significant inverse relationships between serum 25-hydroxyvitamin D levels and the frequencies of mDCs and pDCs in autistic children. Our data suggested that DCs could play a role in the clinical course of ASD. The relationship of DCs to immune disorders in ASD remains to be determined.