Neuronal regulation of the gut immune system and neuromodulation for treating inflammatory bowel disease

Unravelling the role of beta-CGRP in inflammatory bowel disease and its potential role in gastrointestinal homeostasis

BACKGROUND

The role of beta calcitonin gene-related peptide (beta-CGRP) in gastrointestinal tract is obscure, but experimental models suggest an effect on the homeostasis of the intestinal mucosa. We measured beta-CGRP circulating levels in a large series of subjects with a recent diagnosis of inflammatory bowel disease (IBD), in order to assess the potential role of this neuropeptide in IBD pathogenesis.

METHODS

Morning serum beta-CGRP levels were measured by ELISA (CUSABIO, China) in 96 patients recently diagnosed of IBD and compared with those belonging from 50 matched healthy controls (HC) and 50 chronic migraine (CM) patients.

RESULTS

Beta-CGRP levels were lower in patients with IBD (3.1 ± 1.9 pg/mL; 2.9 [2.4-3.4] pg/mL) as compared to HC (4.7 ± 2.6; 4.9 [4.0-5.8] pg/mL; p < 0.001) and to CM patients (4.6 ± 2.6; 4.7 [3.3-6.2] pg/mL; p < 0.001). Beta-CGRP levels in CM were not significantly different to those of HC (p = 0.92). Regarding IBD diagnostic subtypes, beta-CGRP levels for ulcerative colitis (3.0 ± 1.9pg/mL; 2.5 [2.1-3.4] pg/mL) and Crohn's disease (3.3 ± 2.0 pg/mL; 3.2 [2.4-3.9] pg/mL) were significantly lower to those of HC (p < 0.01 and p < 0.05, respectively) and CM (p < 0.01 and p < 0.05, respectively).

CONCLUSIONS

We have found a significant reduction in serum beta-CGRP levels in patients with a recent diagnosis of all kinds of IBD as compared to two control groups without active intestinal disease, HC and CM, which may suggest a role for this neuropeptide in the pathophysiology of IBD. Our data indicate a protective role of beta-CGRP in the homeostasis of the alimentary tract.

Applications and perspectives of tumor organoids in radiobiology (Review)

Radiotherapy exhibits significant versatility and efficacy in cancer treatment, thereby playing a crucial role in the field of oncology. However, there remains an urgent need for extensive research on various aspects of radiotherapy, including target selection, damage repair and its combination with immunotherapy. Particularly, the development of in vitro models to replicate in vivo tumor lesion responses is vital. The present study provides a thorough review of the establishment and application of tumor organoids in radiotherapy, aiming to explore their potential impact on cancer treatment.

New insights into the effects of serotonin on Parkinson's disease and depression through its role in the gastrointestinal tract

Neuropsychiatric and neurodegenerative disorders are frequently associated with gastrointestinal (GI) co-pathologies. Although the central and enteric nervous systems (CNS and ENS, respectively) have been studied separately, there is increasing interest in factors that may contribute to conditions affecting both systems. There is compelling evidence that serotonin (5-HT) may play an important role in several gut-brain disorders. It is well known that 5-HT is essential for the development and functioning of the CNS. However, most of the body's 5-HT is produced in the GI tract. A deeper understanding of the specific effects of enteric 5-HT on gut-brain disorders may provide the basis for the development of new therapeutic targets. This review summarizes current data focusing on the important role of 5-HT in ENS development and motility, with particular emphasis on novel aspects of 5-HT signaling in conditions where CNS and ENS comorbidities are common, such as Parkinson's disease and depressive disorders.

Dopamine β-hydroxylase shapes intestinal inflammation through modulating T cell activation

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic and relapsing disease characterized by immune-mediated dysfunction of intestinal homeostasis. Alteration of the enteric nervous system and the subsequent neuro-immune interaction are thought to contribute to the initiation and progression of IBD. However, the role of dopamine beta-hydroxylase (DBH), an enzyme converting dopamine into norepinephrine, in modulating intestinal inflammation is not well defined.

METHODS

CD4+CD45RBhighT cell adoptive transfer, and 2,4-dinitrobenzene sulfonic acid (DNBS) or dextran sodium sulfate (DSS)-induced colitis were collectively conducted to uncover the effects of DBH inhibition by nepicastat, a DBH inhibitor, in mucosal ulceration, disease severity, and T cell function.

RESULTS

Inhibition of DBH by nepicastat triggered therapeutic effects on T cell adoptive transfer induced chronic mouse colitis model, which was consistent with the gene expression of DBH in multiple cell populations including T cells. Furthermore, DBH inhibition dramatically ameliorated the disease activity and colon shortening in chemically induced acute and chronic IBD models, as evidenced by morphological and histological examinations. The reshaped systemic inflammatory status was largely associated with decreased pro-inflammatory mediators, such as TNF-α, IL-6 and IFN-γ in plasma and re-balanced Th1, Th17 and Tregs in mesenteric lymph nodes (MLNs) upon colitis progression. Additionally, the conversion from dopamine (DA) to norepinephrine (NE) was inhibited resulting in increase in DA level and decrease in NE level and DA/NE showed immune-modulatory effects on the activation of immune cells.

CONCLUSION

Modulation of neurotransmitter levels via inhibition of DBH exerted protective effects on progression of murine colitis by modulating the neuro-immune axis. These findings suggested a promising new therapeutic strategy for attenuating intestinal inflammation.

Differences in circulating alpha-calcitonin gene-related peptide levels in inflammatory bowel disease and its relation to migraine comorbidity: A cross-sectional study

OBJECTIVE

To analyze the specificity of calcitonin gene-related peptide (CGRP) levels, we measured alpha-CGRP circulating levels in a large series of patients with a recent diagnosis of inflammatory bowel disease (IBD) who were interviewed regarding comorbid headache.

BACKGROUND

Several studies have found an association between migraine and IBD.

METHODS

In this cross-sectional study performed in an IBD clinic, morning serum alpha-CGRP levels were measured by enzyme-linked immunosorbent assay in 96 patients who were recently diagnosed with IBD and compared to those from 50 similar patients with chronic migraine (CM) and 50 healthy controls (HC).

RESULTS

Alpha-CGRP levels were higher in patients with IBD (median [interquartile range] 56.9 [35.6-73.9] pg/mL) and patients with CM (53.0 [36.7-73.9] pg/mL) compared to HC (37.2 [30.0-51.8] pg/mL; p = 0.003; p = 0.019, respectively). Regarding IBD diagnostic subtypes, alpha-CGRP levels for ulcerative colitis (67.2 ± 49.3 pg/mL; 57.0 [35.6-73.4] pg/mL) and Crohn's disease (54.9 ± 27.5 pg/mL; 57.7 [29.1-76.1] pg/mL) were significantly higher than those of HC (p = 0.013, p = 0.040, respectively). Alpha-CGRP levels were further different in patients with IBD with migraine (70.9 [51.8-88.7] pg/mL) compared to HC (p < 0.001), patients with IBD without headache (57.5 [33.3-73.8] pg/mL; p = 0.049), and patients with IBD with tension-type headache but without migraine (41.7 [28.5-66.9] pg/mL; p = 0.004), though alpha-CGRP levels in patients with IBD without migraine (53.7 [32.9-73.5] pg/mL) remained different over HC (p = 0.028).

CONCLUSION

Together with CM, circulating alpha-CGRP levels are different in patients with IBD, perhaps reflecting a chronic inflammatory state. IBD is an example of how alpha-CGRP levels are not a totally specific migraine biomarker. However, alpha-CGRP levels were further increased in patients with IBD who have a history of migraine, which reinforces its role as a biomarker in migraine patients, always bearing in mind their comorbidities.

Neuroimmunophysiology of the gastrointestinal tract

Gut physiology is the epicenter of a web of internal communication systems (i.e., neural, immune, hormonal) mediated by cell-cell contacts, soluble factors, and external influences, such as the microbiome, diet, and the physical environment. Together these provide the signals that shape enteric homeostasis and, when they go awry, lead to disease. Faced with the seemingly paradoxical tasks of nutrient uptake (digestion) and retarding pathogen invasion (host defense), the gut integrates interactions between a variety of cells and signaling molecules to keep the host nourished and protected from pathogens. When the system fails, the outcome can be acute or chronic disease, often labeled as "idiopathic" in nature (e.g., irritable bowel syndrome, inflammatory bowel disease). Here we underscore the importance of a holistic approach to gut physiology, placing an emphasis on intercellular connectedness, using enteric neuroimmunophysiology as the paradigm. The goal of this opinion piece is to acknowledge the pace of change brought to our field via single-cell and -omic methodologies and other techniques such as cell lineage tracing, transgenic animal models, methods for culturing patient tissue, and advanced imaging. We identify gaps in the field and hope to inspire and challenge colleagues to take up the mantle and advance awareness of the subtleties, intricacies, and nuances of intestinal physiology in health and disease by defining communication pathways between gut resident cells, those recruited from the circulation, and "external" influences such as the central nervous system and the gut microbiota.

Dorsal Root Ganglion Stimulation for the Management of Inflammatory Bowel Disease: A Case Report

This case report presents the successful use of dorsal root ganglion stimulation (DRGS) in a 30-year-old female patient with Crohn's disease. Despite extensive treatments, the patient experienced chronic abdominal pain, diarrhea, bloating, cramping, fatigue, and other debilitating symptoms. After a successful DRGS trial with leads placed on the right T6 and T10, she was implanted with a permanent system. At 18 months she continues to experience significant improvement in symptoms, including reduced abdominal pain, decreased defecation frequency, better stool consistency, less pain with eating and bowel evacuation, and enhanced quality of life.

Exploring Electrical Neuromodulation as an Alternative Therapeutic Approach in Inflammatory Bowel Diseases

Background and Objectives: This review systematically evaluates the potential of electrical neuromodulation techniques-vagus nerve stimulation (VNS), sacral nerve stimulation (SNS), and tibial nerve stimulation (TNS)-as alternative treatments for inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's Disease (CD). It aims to synthesize current evidence on the efficacy and safety of these modalities, addressing the significant burden of IBD on patient quality of life and the limitations of existing pharmacological therapies. Materials and Methods: We conducted a comprehensive analysis of studies from PubMed, focusing on research published between 1978 and 2024. The review included animal models and clinical trials investigating the mechanisms, effectiveness, and safety of VNS, SNS, and TNS in IBD management. Special attention was given to the modulation of inflammatory responses and its impact on gastrointestinal motility and functional gastrointestinal disorders associated with IBD. Results: Preliminary findings suggest that VNS, SNS, and TNS can significantly reduce inflammatory markers and improve symptoms in IBD patients. These techniques also show potential in treating related gastrointestinal disorders during IBD remission phases. However, the specific mechanisms underlying these benefits remain to be fully elucidated, and there is considerable variability in treatment parameters. Conclusions: Electrical neuromodulation holds promise as a novel therapeutic avenue for IBD, offering an alternative to patients who do not respond to traditional treatments or experience adverse effects. The review highlights the need for further rigorous studies to optimize stimulation parameters, understand long-term outcomes, and integrate neuromodulation effectively into IBD treatment protocols.

A ganglionic intestinointestinal reflex activated by acute noxious challenge

To investigate noxious stimulation-responsive neural circuits that could influence the gut, we recorded from intestinally directed (efferent) nerve filaments dissected from mesenteric nerves close to the small intestine in anesthetized rats. These exhibited baseline multiunit activity that was almost unaffected by vagotomy (VagX) and reduced only slightly by cutting the splanchnic nerves. The activity was halved by hexamethonium (Hex) treatment. When an adjacent gut segment received an intraluminal stimulus 2,4,6-trinitrobenzenesulfonate (TNBS) in 30% ethanol, mesenteric efferent nerve activity increased for more than 1 h. The increased activity was almost unaffected by bilateral vagotomy or splanchnic nerve section, indicating a lack of central nervous involvement, but it was 60% reduced by hexamethonium. Spike sorting discriminated efferent single and predominantly single-unit spike trains that responded to TNBS, were unaffected by splachnectomy but were silenced by hexamethonium. After noxious stimulation of one segment, the adjacent segment showed no evidence of suppression of gut motility or vasoconstriction. We conclude that luminal application of a noxious stimulus to the small intestine activates an entirely peripheral, intestinointestinal reflex pathway. This pathway involves enteric intestinofugal neurons that excite postganglionic sympathetic neurons via a nicotinic synapse. We suggest that the final sympathetic efferent neurons that respond to a tissue damaging stimulus are distinct from vasoconstrictor, secretomotor, and motility inhibiting neurons.NEW & NOTEWORTHY An intraluminal noxious chemical stimulus applied to one segment of small intestine increased mesenteric efferent nerve activity to an adjacent segment. This was identified as a peripheral ganglionic reflex that did not require vagal or spinal connections. Hexamethonium blocked most, but not all, ongoing and reflex mesenteric efferent activity. The prevertebral sympathetic efferent neurons that are activated likely affect inflammatory and immune functions of other gut segments.

EphB2 promotes enteric nitrergic hyperinnervation and neurogenic inflammation in DSS-induced chronic colitis in mice

BACKGROUND

Enteric nervous system (ENS) has been closely associated with the neuro-immune response and is currently considered a reliable target for intestinal inflammation. Neuronal nitric oxide synthase (nNOS) nerves are involved in inflammatory diseases by releasing nitric oxide (NO). EphB2 expression and density of innervation of the mucosal layer are positively correlated with the severity of intestinal inflammatory responses. In this study, we hypothesized that a EphB2-mediated mechanism may regulate enteric immunity through modulation of nNOS nerves.

METHODS

Firstly, the Western blot (WB) method was employed to quantify EphB2 expression in the intestinal mucosal layer of DSS mice and assess alterations in nerve fiber activation and density. Immunofluorescence (IF) double staining with nNOS and neuronal marker PGP9.5 was conducted to measure nNOS nerve fiber density within the intestinal mucosal layer of mice. Subsequently, in vivo experiments were performed to investigate the inhibitory or activatory effect of EphB2Fc or EphrinB2Fc on EphB2 expression and activation. Immunoprecipitation experiments confirmed the interaction between EphB2 and nNOS nerves. WB and IF experiments were carried out to evaluate both inflammatory conditions of mouse colonic mucosa following intervention with EphB2Fc/EphrinB2Fc as well as changes in nNOS nerve fibers expression. Finally, in vitro experiments, neurally-mediated inflammation was assessed in the organ bath system by activating intestinal mucosal innervation through Veratridine (VER) and electrical field stimulation (EFS) techniques for 3 h. The activation of nNOS nerves was inhibited by nitroindazole (7NI). WB was employed to detect changes in the expression of inflammatory factors in the intestinal mucosal layer in EphB2Fc/EphrinB2Fc treated mice and control group.

KEY RESULTS

We found that the expression of EphB2 and density nNOS nerve fibers in the intestinal mucosa were positively correlated with the colitis response. Blocking (EphB2Fc)/activating (EphrinB2Fc) EphB2 in vivo significantly reduced/increased the density of nNOS nerve fibers and expression of inflammatory factors in colonic mucosa of DSS treated mice. In vitro, blocking nNOS nerves activation attenuated the inflammatory reaction induced by either EFS or EphB2.

CONCLUSIONS

Our findings provided evidence that EphB2 mediated regulation of innate immunity-ENS crosstalk might represent an attractive target for novel therapeutic strategies in ulcerative colitis.

Mucosal neuroimmune mechanisms in gastro-oesophageal reflux disease (GORD) pathogenesis

Gastro-oesophageal reflux disease (GORD) is a chronic condition characterised by visceral pain in the distal oesophagus. The current first-line treatment for GORD is proton pump inhibitors (PPIs), however, PPIs are ineffective in a large cohort of patients and long-term use may have adverse effects. Emerging evidence suggests that nerve fibre number and location are likely to play interrelated roles in nociception in the oesophagus of GORD patients. Simultaneously, alterations in cells of the oesophageal mucosa, namely epithelial cells, mast cells, dendritic cells, and T lymphocytes, have been a focus of GORD research for several years. The oesophagus of GORD patients exhibits both macro- and micro-inflammation as a response to chronic acidic reflux at the epithelium. In other conditions of the GI tract, such as IBS and IBD, well-characterised bidirectional processes between immune cells and mucosal nerve fibres contribute to pathogenesis and symptom generation. Sensory alterations in these conditions such as nerve fibre outgrowth and hypersensitivity can be driven by inflammatory processes, which promote visceral pain signalling. This review will examine what is currently known of the molecular pathways linking inflammation and sensory perception leading to the development of GORD symptoms and explore potentially relevant mechanisms in other GI regions which may indicate new areas in GORD research.

Interleukin-10 signaling in somatosensory neurons controls CCL2 release and inflammatory response

Appropriate regulation of the inflammatory response is essential for survival. Interleukin-10 (IL-10), a well-known anti-inflammatory cytokine, plays a major role in controlling inflammation. In addition to immune cells, we previously demonstrated that the IL-10 receptor (IL-10R1) is expressed in dorsal root ganglion sensory neurons. There is emerging evidence that these sensory neurons contribute to immunoregulation, and we hypothesized that IL-10 signaling in dorsal root ganglion (DRG) neurons facilitates the regulation of the inflammatory response. We showed that mice that lack IL-10R1 specifically on advillin-positive neurons have exaggerated blood nitric oxide levels, spinal microglia activation, and cytokine upregulation in the spinal cord, liver, and gut compared to wild-type (WT) counterparts in response to systemic lipopolysaccharide (LPS) injection. Lack of IL-10R1 in DRG and trigeminal ganglion (TG) neurons also increased circulating and DRG levels of proinflammatory C-C motif chemokine ligand 2 (CCL2). Interestingly, analysis of published scRNA-seq data revealed that Ccl2 and Il10ra are expressed by similar types of DRG neurons; nonpeptidergic P2X purinoceptor (P2X3R + ) neurons. In primary cultures of DRG neurons, we demonstrated that IL-10R1 inhibits the production of CCL2, but not that of the neuropeptides substance P and calcitonin-gene related peptide (CGRP). Furthermore, our data indicate that ablation of Transient receptor potential vanilloid (TRPV)1 + neurons does not impact the regulation of CCL2 production by IL-10. In conclusion, we showed that IL-10 binds to its receptor on sensory neurons to downregulate CCL2 and contribute to immunoregulation by reducing the attraction of immune cells by DRG neuron-derived CCL2. This is the first evidence that anti-inflammatory cytokines limit inflammation through direct binding to receptors on sensory neurons. Our data also add to the growing literature that sensory neurons have immunomodulatory functions.

The Eph/ephrin system symphony of gut inflammation

The extent of gut inflammation depends largely on the gut barrier's integrity and enteric neuroimmune interactions. However, the factors and molecular mechanisms that regulate inflammation-related changes in the enteric nervous system (ENS) remain largely unexplored. Eph/ephrin signaling is critical for inflammatory response, neuronal activation, and synaptic plasticity in the brain, but its presence and function in the ENS have been largely unknown to date. This review discusses the critical role of Eph/ephrin in regulating gut homeostasis, inflammation, neuroimmune interactions, and pain pathways. Targeting the Eph/ephrin system offers innovative treatments for gut inflammation disorders, offering hope for enhanced patient prognosis, pain management, and overall quality of life.

Enteric neuro-immune interactions in intestinal health and disease

The enteric nervous system is an autonomous neuronal circuit that regulates many processes far beyond the peristalsis in the gastro-intestinal tract. This circuit, consisting of enteric neurons and enteric glial cells, can engage in many intercellular interactions shaping the homeostatic microenvironment in the gut. Perhaps the most well documented interactions taking place, are the intestinal neuro-immune interactions which are essential for the fine-tuning of oral tolerance. In the context of intestinal disease, compelling evidence demonstrates both protective and detrimental roles for this bidirectional neuro-immune signaling. This review discusses the different immune cell types that are recognized to engage in neuronal crosstalk during intestinal health and disease. Highlighting the molecular pathways involved in the neuro-immune interactions might inspire novel strategies to target intestinal disease.

Bidirectional crosstalk between the peripheral nervous system and lymphoid tissues/organs

The central nervous system (CNS) influences the immune system generally by regulating the systemic concentration of humoral substances (e.g., cortisol and epinephrine), whereas the peripheral nervous system (PNS) communicates specifically with the immune system according to local interactions/connections. An imbalance between the components of the PNS might contribute to pathogenesis and the further development of certain diseases. In this review, we have explored the "thread" (hardwiring) of the connections between the immune system (e.g., primary/secondary/tertiary lymphoid tissues/organs) and PNS (e.g., sensory, sympathetic, parasympathetic, and enteric nervous systems (ENS)) in health and disease in vitro and in vivo. Neuroimmune cell units provide an anatomical and physiological basis for bidirectional crosstalk between the PNS and the immune system in peripheral tissues, including lymphoid tissues and organs. These neuroimmune interactions/modulation studies might greatly contribute to a better understanding of the mechanisms through which the PNS possibly affects cellular and humoral-mediated immune responses or vice versa in health and diseases. Physical, chemical, pharmacological, and other manipulations of these neuroimmune interactions should bring about the development of practical therapeutic applications for certain neurological, neuroimmunological, infectious, inflammatory, and immunological disorders/diseases.

Guardians of the gut: influence of the enteric nervous system on the intestinal epithelial barrier

The intestinal mucosal surface forms one of the largest areas of the body, which is in direct contact with the environment. Co-ordinated sensory functions of immune, epithelial, and neuronal cells ensure the timely detection of noxious queues and potential pathogens and elicit proportional responses to mitigate the threats and maintain homeostasis. Such tuning and maintenance of the epithelial barrier is constantly ongoing during homeostasis and its derangement can become a gateway for systemic consequences. Although efforts in understanding the gatekeeping functions of immune cells have led the way, increasing number of studies point to a crucial role of the enteric nervous system in fine-tuning and maintaining this delicate homeostasis. The identification of immune regulatory functions of enteric neuropeptides and glial-derived factors is still in its infancy, but has already yielded several intriguing insights into their important contribution to the tight control of the mucosal barrier. In this review, we will first introduce the reader to the current understanding of the architecture of the enteric nervous system and the epithelial barrier. Next, we discuss the key discoveries and cellular pathways and mediators that have emerged as links between the enteric nervous, immune, and epithelial systems and how their coordinated actions defend against intestinal infectious and inflammatory diseases. Through this review, the readers will gain a sound understanding of the current neuro-immune-epithelial mechanisms ensuring intestinal barrier integrity and maintenance of intestinal homeostasis.

Characterization of prokineticin system in Crohn's disease pathophysiology and pain, and its modulation by alcohol abuse: A preclinical study

BACKGROUND

Crohn's disease-(CD) pathogenesis is still unknown and chronic pain is a frequent symptom in CD-patients. Identifying novel therapeutic targets and predisposing factors is a primary goal. In this regard, prokineticin system-(PKS) appears a promising target.

AIMS AND METHODS

TNBS-model was used. DAI, abdominal and visceral pain, and muscle strength were monitored. CD-mice were sacrificed at two times (day 7 and 14 after TNBS) in order to identify PKS involvement in CD pathophysiology and pain. PKS characterization was performed in mesenteric lymph nodes-(MLN), colon, myenteric plexus-(MP), dorsal root ganglia-(DRGs) and spinal cord-(SC). Inflammation/neuroinflammation was also assessed in the same tissues. In order to evaluate alcohol abuse as a possible trigger for CD and its effect on PKS activation, naïve mice were administered (oral-gavage) with ethanol for 10 consecutive days. PKS as well as inflammation/neuroinflammation were evaluated in MLN, colon and MP.

RESULTS

TNBS treated-mice showed a rapid increase in DAI, abdominal/visceral hypersensitivity and a progressive strength loss. In all tissue analysed of CD-mice, a quick and significant increase of mRNA of PKs and PKRs was observed, associated with an increase of pro-inflammatory cytokines (IL-1β, IL-6 and TNFα) and macrophage/glia markers (iba1, CD11b and GFAP) levels. In alcohol abuse model, ethanol induced in colon and MP a significant PKS activation accompanied by inflammation/neuroinflammation.

CONCLUSIONS

We can assume that PKS may be involved in CD development and pain. Furthermore, alcohol appears to activate PKS and may be a trigger factor for CD.

A comparative recognition research on excretory organism in medical applications using artificial neural networks

Purpose: In the contemporary era, a significant number of individuals encounter various health issues, including digestive system ailments, even during their advanced years. The major purpose of this study is based on certain observations that are made in internal digestive systems in order to prevent severe cause that usually occurs in elderly people. Approach: To solve the purpose of the proposed method the proposed system is introduced with advanced features and parametric monitoring system that are based on wireless sensor setups. The parametric monitoring system is integrated with neural network where certain control actions are taken to prevent gastrointestinal activities at reduced data loss. Results: The outcome of the combined process is examined based on four different cases that is designed based on analytical model where control parameters and weight establishments are also determined. As the internal digestive system is monitored the data loss that is present with wireless sensor network must be reduced and proposed approach prevents such data loss with an optimized value of 1.39%. Conclusion: Parametric cases were conducted to evaluate the efficacy of neural networks. The findings indicate a significantly higher effectiveness rate of approximately 68% when compared to the control cases.

Relationship between IL-22 and IL-22BP in diabetic cognitive dysfunction

BACKGROUND

CD4 + T helper (Th)22 cells play a regulatory role in autoimmune diseases such as type 1 diabetes mellitus. The Th22-related cytokine interleukin (IL)-22, the expression of which is increased in diabetes mellitus (DM), can act as a neurotrophic factor to protect neurons from apoptosis. Paradoxically, neuronal apoptosis and learning and memory decline occur in DM. In this study, we investigated the relationship between IL-22 and its receptors IL-22Rα1 and IL-22 binding protein (IL-22BP, a soluble inhibitor of IL-22) in diabetic encephalopathy (DE) and the effects of IL-22 on hippocampal neurons, learning and memory.

METHODS

A C57BL/6 mouse model of diabetes was constructed by intraperitoneal injection of streptozotocin. The mice were randomly divided into 4 groups: the control group, diabetes group, diabetes + recombinantIL-22 (rIL-22) group and diabetes + IL-22BP group. The Morris water maze test was used to evaluate learning and memory, the expression of IL-22 was measured by ELISA, and Evans Blue staining was used to evaluate blood-brain barrier permeability. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to measure the mRNA expression of IL-22 and IL-22Rα1 in the hippocampus. The morphology and number of hippocampal neurons were assessed by Nissl staining, and TUNEL staining was used to detect hippocampal neuronal apoptosis. Immunofluorescence was used to analyze IL-22Rα1 expression and localization in hippocampus, and Western blotting was used to evaluate the expression of IL-22, IL-22Rα1, IL-22BP, and the apoptosis related proteins Caspase-3 and C-caspase-3.

RESULTS

Compared with those in the control group, mice in the diabetes group showed cognitive decline; apoptosis of hippocampal neurons; increased expression of hippocampal Caspase-3, C-Caspase-3, IL-22, IL-22Rα1, and IL-22BP; and a decreased IL-22/IL-22BP ratio. Learning and memory were improved, neuronal apoptosis was attenuated, IL-22Rα1 expression and the IL-22/IL-22BP ratio were increased, and caspase-3 and C-caspase-3 expression was decreased in the rIL-22-treated group compared with the diabetes group. IL-22BP treatment aggravated diabetic cognitive dysfunction and pathological alterations in the hippocampus, decreased the IL-22/IL-22BP ratio, and increased the expression of caspase-3 and C-caspase-3 in mice with diabetes.

CONCLUSION

A decrease in the IL-22/IL-22BP ratio plays an important role in diabetic cognitive dysfunction, and rIL-22 can effectively alleviate DE. Herein, we shed light on the interaction between IL-22 and IL-22BP as therapeutic targets for DM.

The enteric nervous system

Of all the organ systems in the body, the gastrointestinal tract is the most complicated in terms of the numbers of structures involved, each with different functions, and the numbers and types of signaling molecules utilized. The digestion of food and absorption of nutrients, electrolytes, and water occurs in a hostile luminal environment that contains a large and diverse microbiota. At the core of regulatory control of the digestive and defensive functions of the gastrointestinal tract is the enteric nervous system (ENS), a complex system of neurons and glia in the gut wall. In this review, we discuss 1) the intrinsic neural control of gut functions involved in digestion and 2) how the ENS interacts with the immune system, gut microbiota, and epithelium to maintain mucosal defense and barrier function. We highlight developments that have revolutionized our understanding of the physiology and pathophysiology of enteric neural control. These include a new understanding of the molecular architecture of the ENS, the organization and function of enteric motor circuits, and the roles of enteric glia. We explore the transduction of luminal stimuli by enteroendocrine cells, the regulation of intestinal barrier function by enteric neurons and glia, local immune control by the ENS, and the role of the gut microbiota in regulating the structure and function of the ENS. Multifunctional enteric neurons work together with enteric glial cells, macrophages, interstitial cells, and enteroendocrine cells integrating an array of signals to initiate outputs that are precisely regulated in space and time to control digestion and intestinal homeostasis.

Ion channel regulation of gut immunity

Mounting evidence indicates that gastrointestinal (GI) homeostasis hinges on communications among many cellular networks including the intestinal epithelium, the immune system, and both intrinsic and extrinsic nerves innervating the gut. The GI tract, especially the colon, is the home base for gut microbiome which dynamically regulates immune function. The gut's immune system also provides an effective defense against harmful pathogens entering the GI tract while maintaining immune homeostasis to avoid exaggerated immune reaction to innocuous food and commensal antigens which are important causes of inflammatory disorders such as coeliac disease and inflammatory bowel diseases (IBD). Various ion channels have been detected in multiple cell types throughout the GI tract. By regulating membrane properties and intracellular biochemical signaling, ion channels play a critical role in synchronized signaling among diverse cellular components in the gut that orchestrates the GI immune response. This work focuses on the role of ion channels in immune cells, non-immune resident cells, and neuroimmune interactions in the gut at the steady state and pathological conditions. Understanding the cellular and molecular basis of ion channel signaling in these immune-related pathways and initial testing of pharmacological intervention will facilitate the development of ion channel-based therapeutic approaches for the treatment of intestinal inflammation.

A Novel Method for Identifying the Transition Zone in Long-Segment Hirschsprung Disease: Investigating the Muscle Unit to Ganglion Ratio

Hirschsprung disease (HSCR) is characterised by the absence of enteric ganglia along variable lengths of the distal bowel. Current gold standard treatment involves the surgical resection of the defective, aganglionic bowel. Clear and reliable distinction of the normoganglionated bowel from the transition zone is key for successful resection of the entire defective bowel, and the avoidance of subsequent postoperative complications. However, the intraoperative nature of the tissue analysis and the variability of patient samples, sample preparation, and operator objectivity, make reproducible identification of the transition zone difficult. Here, we have described a novel method for using muscle units as a distinctive landmark for quantifying the density of enteric ganglia in resection specimens from HSCR patients. We show that the muscle unit to ganglion ratio is greater in the transition zone when compared with the proximal, normoganglionated region for long-segment HSCR patients. Patients with short-segment HSCR were also investigated, however, the muscle unit to ganglion ratio was not significantly different in these patients. Immunohistochemical examination of individual ganglia showed that there were no differences in the proportions of either enteric neurons or glial cells through the different regions of the resected colon. In addition, we identified that the size of enteric ganglia was smaller for patients that went on to develop HSCR associated enterocolitis; although the density of ganglia, as determined by the muscle unit to ganglia ratio, was not different when compared with patients that had no further complications. This suggests that subtle changes in the enteric nervous system, even in the “normoganglionated” colon, could be involved in changes in immune function and subsequent bacterial dysbiosis.

Colitis and Colorectal Carcinogenesis: The Focus on Isolated Lymphoid Follicles

Gut-associated lymphoid tissue is one of the most diverse and complex immune compartments in the human body. The subepithelial compartment of the gut consists of immune cells of innate and adaptive immunity, non-hematopoietic mesenchymal cells, and stem cells of different origins, and is organized into secondary (and even tertiary) lymphoid organs, such as Peyer's patches, cryptopatches, and isolated lymphoid follicles. The function of isolated lymphoid follicles is multifaceted; they play a role in the development and regeneration of the large intestine and the maintenance of (immune) homeostasis. Isolated lymphoid follicles are also extensively associated with the epithelium and its conventional and non-conventional immune cells; hence, they can also function as a starting point or maintainer of pathological processes such as inflammatory bowel diseases or colorectal carcinogenesis. These relationships can significantly affect both physiological and pathological processes of the intestines. We aim to provide an overview of the latest knowledge of isolated lymphoid follicles in colonic inflammation and colorectal carcinogenesis. Further studies of these lymphoid organs will likely lead to an extended understanding of how immune responses are initiated and controlled within the large intestine, along with the possibility of creating novel mucosal vaccinations and ways to treat inflammatory bowel disease or colorectal cancer.