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1.
Gut Microbes ; 16(1): 2413367, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39482844

RESUMO

The International Rome Committee defines Disorders of Gut-Brain Interactions (DGBI) based upon distinct combinations of chronic and/or recurrent unexplained gastrointestinal symptoms. Yet patients often experience overlapping DGBI. Patients with DGBI frequently also suffer from extraintestinal symptoms, including fatigue, sleep disturbances, anxiety, and depression. Patients with overlapping DGBI typically experience more severe GI symptoms and increased psychosocial burden. Concerning the pathophysiology, DGBI are associated with disruptions in gut motility, function of the brain and enteric neurons, immune function, and genetic markers, with recent findings revealing gut microbiome alterations linked to these mechanisms of DGBI. Emerging evidence summarized in this review suggests that the microbiome influences various established disease mechanisms of different DGBI groups. Overall, changes in the gastrointestinal microbiome do not seem to be linked to a specific DGBI subgroup but may play a key role in the manifestation of different DGBI and, subsequently, overlap of DGBI. Understanding these shared mechanisms and the role of the gastrointestinal microbiome, particularly for overlapping DGBI, might aid in developing more precise diagnostic criteria and treatment strategies while developing personalized interventions that target specific mechanisms to improve patient outcomes.


Assuntos
Eixo Encéfalo-Intestino , Microbioma Gastrointestinal , Humanos , Eixo Encéfalo-Intestino/fisiologia , Encéfalo/microbiologia , Encéfalo/fisiopatologia , Gastroenteropatias/microbiologia , Gastroenteropatias/fisiopatologia , Animais , Motilidade Gastrointestinal/fisiologia
2.
J Pak Med Assoc ; 74(10 (Supple-8)): S437-S441, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39434357

RESUMO

OBJECTIVE: To investigate the relationship between dietary fibres and muscularis externa layer. METHODS: The experimental study was conducted at the Anatomy Department of the College of Medicine, Al- Nahrain University, Iraq, from November 2020 to April 2021, and comprised adult healthy males. They were divided randomly into experimental group A and control group B. Group A was fed high-fibre diet, and group B was fed standard pellet diet. The tissue samples were harvested at day 30 post-surgery. The stomach samplings were placed in 10% neutral formalin for 24 hours to obtain paraffin sections for routine histological and immunohistochemical staining. The protein expression in stomach's smooth muscle of each group was detected by immunohistochemical staining. Data was analysed using SPSS 24. RESULTS: Of the 20 mice, 10(50%) were in each of the two groups. Group A exhibited significant weight-gain compared to group B (p≤0.01). There was significant reduction in the thickness of the muscularis layer in group A compared to group B (p≤0.01). Anoctamin 1 expression in group A was significantly lower than that in group B (p≤0.01). CONCLUSIONS: The stress induced by an unstable fibre diet significantly affected the stomach by decreasing the muscularis layer thickness and Anoctamin 1 expression in interstitial cells of Cajal.


Assuntos
Fibras na Dieta , Estômago , Animais , Masculino , Camundongos , Fibras na Dieta/farmacologia , Estômago/patologia , Motilidade Gastrointestinal/fisiologia , Músculo Liso/metabolismo , Músculo Liso/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia
4.
Nat Commun ; 15(1): 8123, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285207

RESUMO

The vagus nerve (VN) extensively innervates the gastric enteric nervous system (ENS), but its influence on gastric ENS functionality and motility in vivo remains unclear due to technical challenges. Here we describe a method for stable, long-term observation of gastric ENS activity and muscle dynamics at cellular resolution, which can also be extended to intestinal applications. This method involves ENS-specific labeling and the implantation of an abdominal wall window for optical recording in male mice. In vivo calcium imaging reveals a linear relationship between vagal stimulation frequency and myenteric neuron activation in gastric antrum. Furthermore, the motility of gastric antrum is significantly enhanced and shows a positive correlation with the intensity and number of activated myenteric neurons. While vagal stimulation also activates proximal colonic myenteric neurons, this activation is not frequency-dependent and does not induce proximal colonic motility. The method and results provide important insights into VN-ENS interactions in vivo, advancing our understanding of gastrointestinal motility regulation.


Assuntos
Motilidade Gastrointestinal , Plexo Mientérico , Nervo Vago , Animais , Nervo Vago/fisiologia , Masculino , Motilidade Gastrointestinal/fisiologia , Camundongos , Trato Gastrointestinal/inervação , Cálcio/metabolismo , Colo/inervação , Neurônios/fisiologia , Camundongos Endogâmicos C57BL , Imagem Óptica/métodos , Sistema Nervoso Entérico/fisiologia , Antro Pilórico/inervação , Antro Pilórico/diagnóstico por imagem
5.
Open Vet J ; 14(8): 1801-1807, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39308735

RESUMO

Background: Colic, a primary cause of illness and death in horses, necessitates the development of improved prognostic tools. Aim: The aim of this study was to investigate the prognostic significance of physiological and biochemical parameters in horses suffering from colic. Methods: A comprehensive clinical evaluation of 117 horses included assessment of heart rate, mucous membranes, capillary refill time, rectal temperature, respiratory rate, gut motility, reflux, and limb pulse strength. Results: Stomach reflux, absence of gut noises, and increased heart rate (mean increase of 12 bpm) strongly correlate with a poor prognosis. Prolonged capillary refill time (mean increase of 3 seconds), rectal temperature (over 38.5°C), elevated packed cell volume (mean increase of 4%), and blood lactate levels (mean increase of 5 mmol/l) underscore the significance of these markers. Notably, blood lactate (p < 0.001), gut noises (p < 0.05), and heart rate (p < 0.001) demonstrate the highest predictive significance based on statistical analysis. Conclusion: Future research should investigate the prognostic potential of additional parameters and assess the impact of recommended treatments on colic prognosis. This data-driven study emphasizes the critical role of early recognition and thorough assessment in colic cases, offering vital insights into improving equine healthcare and mitigating mortality rates.


Assuntos
Cólica , Doenças dos Cavalos , Cavalos , Animais , Cólica/veterinária , Cólica/sangue , Cólica/mortalidade , Cólica/diagnóstico , Doenças dos Cavalos/sangue , Doenças dos Cavalos/diagnóstico , Doenças dos Cavalos/fisiopatologia , Prognóstico , Masculino , Feminino , Frequência Cardíaca/fisiologia , Taxa Respiratória/fisiologia , Ácido Láctico/sangue , Temperatura Corporal/fisiologia , Motilidade Gastrointestinal/fisiologia , Biomarcadores/sangue
6.
Nutrients ; 16(18)2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39339669

RESUMO

Food intake regulation is a complex mechanism involving the interaction between central and peripheral structures. Among the latter, the gastrointestinal tract represents one of the main sources of both nervous and hormonal signals, which reach the central nervous system that integrates them and sends the resulting information downstream to effector organs involved in energy homeostasis. Gut hormones released by nutrient-sensing enteroendocrine cells can send signals to central structures involved in the regulation of food intake through more than one mechanism. One of these is through the modulation of gastric motor phenomena known to be a source of peripheral satiety signals. In the present review, our attention will be focused on the ability of the glucagon-like peptide 2 (GLP-2) hormone to modulate gastrointestinal motor activity and discuss how its effects could be related to peripheral satiety signals generated in the stomach and involved in the regulation of food intake through the gut-brain axis. A better understanding of the possible role of GLP-2 in regulating food intake through the gut-brain axis could represent a starting point for the development of new strategies to treat some pathological conditions, such as obesity.


Assuntos
Eixo Encéfalo-Intestino , Ingestão de Alimentos , Peptídeo 2 Semelhante ao Glucagon , Peptídeo 2 Semelhante ao Glucagon/fisiologia , Peptídeo 2 Semelhante ao Glucagon/metabolismo , Humanos , Ingestão de Alimentos/fisiologia , Animais , Eixo Encéfalo-Intestino/fisiologia , Trato Gastrointestinal/fisiologia , Trato Gastrointestinal/metabolismo , Encéfalo/fisiologia , Encéfalo/metabolismo , Motilidade Gastrointestinal/fisiologia
7.
Neurogastroenterol Motil ; 36(11): e14907, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39223844

RESUMO

BACKGROUND: The diagnosis of small bowel motility disorders is performed by manometric evaluation of the contractile patterns of the small intestine. Conventional intestinal manometry systems include few pressure sensors at relatively long intervals. We have recently shown that high-resolution jejunal manometry, with multiple closely spaced recording sites, allows the analysis of propagation patterns of intestinal motility in healthy subjects that cannot be detected with conventional manometry. The objective of this pilot study was to explore the feasibility and diagnostic value of high-resolution intestinal manometry in patients with suspected small bowel dysmotility. METHODS: Prospective pilot study evaluating intestinal motility patterns in 16 consecutive patients (16-61 years; 11 women) with severe, chronic digestive symptoms referred for the evaluation of intestinal motility and in 18 healthy controls (21-38 years; 8 women). A 36-channel high-resolution manometry catheter was orally placed under radiological guidance in the jejunum. Intestinal motility was continuously recorded for 3 h fasting and 2 h after a 450 kcal meal. The manometric recordings were analyzed in two formats: (a) with the high-resolution data from 34 channels and (b) showing only the recordings from 5 channels separated by 7 cm intervals, mimicking a conventional manometry recording. KEY RESULTS: In the analysis mimicking conventional manometry, abnormal motility criteria were detected in six patients and in no healthy subject [bursts (n = 3), postprandial minute rhythm (n = 1) and myopathic pattern (n = 2)]. These classical dysmotility criteria were also detected by high-resolution manometry. High-resolution analysis detected one or more abnormal findings in seven additional patients that were not observed in any healthy subject, specifically: (a) abnormal propagation of Phase III (n = 3); (b) reduced propagated activity during Fasting Phase II (n = 4); (c) increased propagated activity during Fasting Phase II and postprandial phase (n = 1). CONCLUSIONS AND INFERENCES: This pilot study suggests that high-resolution intestinal manometry may improve the sensitivity of conventional manometry in the detection of intestinal motor dysfunction.


Assuntos
Motilidade Gastrointestinal , Intestino Delgado , Manometria , Humanos , Manometria/métodos , Adulto , Feminino , Pessoa de Meia-Idade , Masculino , Motilidade Gastrointestinal/fisiologia , Adolescente , Projetos Piloto , Intestino Delgado/fisiopatologia , Adulto Jovem , Estudos Prospectivos
8.
Nutrients ; 16(17)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39275271

RESUMO

Normal and optimal functioning of the gastrointestinal tract is paramount to ensure optimal nutrition through digestion, absorption and motility function. Disruptions in these functions can lead to adverse physiological symptoms, reduced quality of life and increased nutritional risk. When disruption or dysfunction of neuromuscular function occurs, motility disorders can be classified depending on whether coordination or strength/velocity of peristalsis are predominantly impacted. However, due to their nonspecific presenting symptoms and overlap with sensory disruption, they are frequently misdiagnosed as disorders of the gut-brain interaction. Motility disorders are a prevalent issue in the pediatric population, with management varying from medical therapy to psychological therapy, dietary manipulation, surgical intervention or a multimodal approach. This narrative review aims to discuss the dietary management of common pediatric motility disorders including gastroesophageal reflux, esophageal atresia, achalasia, gastroparesis, constipation, and the less common but most severe motility disorder, pediatric intestinal pseudo-obstruction.


Assuntos
Gastroenteropatias , Motilidade Gastrointestinal , Humanos , Motilidade Gastrointestinal/fisiologia , Criança , Gastroenteropatias/dietoterapia , Gastroenteropatias/terapia , Gastroenteropatias/fisiopatologia , Pré-Escolar
9.
Lancet Gastroenterol Hepatol ; 9(11): 1052-1064, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39312926

RESUMO

Gastroparesis is a disorder of delayed gastric emptying with associated symptoms of postprandial fullness, early satiety, nausea, vomiting, bloating, and abdominal pain. Functional dyspepsia is an upper gastrointestinal disorder of gut-brain interaction that presents with similar symptoms but is defined according to symptom patterns rather than gastric motor dysfunction. Although delayed gastric emptying is a defining feature of gastroparesis, other aspects of gastric neuromuscular dysfunction, such as gastric accommodation and visceral hypersensitivity might contribute to symptoms. Similarly, although functional dyspepsia is not defined by impaired gastric emptying, disordered gastric motility might underlie pathogenesis in some patients with functional dyspepsia. In the last decade, it has been increasingly recognised that these two disorders might represent varying presentations along a common continuum of neuromuscular dysfunction, although with differentiating features with respect to outcomes, diagnosis, and treatments. In this Review, an overview of gastroparesis and functional dyspepsia from the perspective of gastric motility is provided, discussing what is distinct and what is shared between these disorders.


Assuntos
Dispepsia , Esvaziamento Gástrico , Gastroparesia , Humanos , Gastroparesia/fisiopatologia , Gastroparesia/diagnóstico , Dispepsia/fisiopatologia , Dispepsia/diagnóstico , Esvaziamento Gástrico/fisiologia , Motilidade Gastrointestinal/fisiologia
10.
Neurogastroenterol Motil ; 36(11): e14891, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39155460

RESUMO

BACKGROUND: Increasing age increases the incidence of chronic constipation and fecal impaction. The contribution of the natural aging process to this phenotype is unclear. This study explored the effects of age on key motility patterns in the murine colon and determined the contribution that altered neurokinin 2 (NK2) -mediated signaling made to the aging phenotype. METHODS: Mucosal reflexes, colonic migrating motor complexes (CMMCs) and colonic motility assays were explored in isolated ex vivo colons from 3, 12-14, 18- and 24-months old mice and the NK2-mediated response determined. Electrical field stimulation (EFS) or exogenous drug application were used to explore the role of the mucosa in colonic segments. KEY RESULTS: Aging reduced the force of contraction of the distal colon mucosal reflex, the frequency and force of contraction of CMMCs and the NK2-mediated component of both motility patterns. Ondansetron, a 5-HT3 receptor antagonist, blocked a component of both motility patterns in full thickness but not in mucosa-free segments of the distal colon. 5, hydroxytryptamine (5-HT) and EFS-evoked NK2-dependent contractions were reduced with increasing age. Smooth muscle sensitivity to 5-HT or neurokinin A (NKA) was not altered with age. In isolated colon motility assays application of NKA decreased transit time in 24-months colon and the NK2 antagonist GR159897 increased transit times in both 3- and 24-months old colons. CONCLUSIONS AND INFERENCES: Aging impairs key motility patterns in the murine colon. These changes involve a decrease in mucosally-evoked NK2-mediated signaling. Targeting NK2-mediated signaling may provide a novel approach to treating age-related motility disorders in the lower bowel.


Assuntos
Envelhecimento , Colo , Motilidade Gastrointestinal , Mucosa Intestinal , Transdução de Sinais , Animais , Motilidade Gastrointestinal/fisiologia , Motilidade Gastrointestinal/efeitos dos fármacos , Colo/metabolismo , Colo/efeitos dos fármacos , Camundongos , Envelhecimento/fisiologia , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos , Masculino , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Complexo Mioelétrico Migratório/efeitos dos fármacos , Complexo Mioelétrico Migratório/fisiologia , Taquicininas/metabolismo
11.
J Pediatr Gastroenterol Nutr ; 79(5): 976-982, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39206742

RESUMO

OBJECTIVES: The understanding of the impact of tethered cord syndrome (TCS) on the physiology of the colorectal area is limited. Our aim was to describe anorectal and colonic motility in children with TCS and compare the findings to those of children with functional constipation (FC). METHODS: We conducted a retrospective review of children with TCS who had an anorectal manometry (ARM) performed at our institution from January 2011 to September 2023. We recorded demographics, medical and surgical history, clinical symptoms, and treatment at time of ARM, ARM findings (resting pressure, push maneuver, rectal sensation, rectoanal inhibitory reflex [RAIR], and RAIR duration), and the final interpretation of colonic manometry (CM) if performed. We identified age and sex-matched control groups of children with FC. RESULTS: We included 24 children with TCS (50% female) who had ARM testing (median age at ARM 6.0 years, interquartile range 4.0-11.8 years). All children had constipation at time of ARM. Nineteen children had detethering surgery before ARM was performed. No significant differences in ARM parameters were found between children who had detethering surgery before ARM and children with FC. Among the 24 children, 14 also had a CM performed (13/14 after detethering surgery). No significant differences in colonic motility were found between children with a history of TCS and children with FC. CONCLUSIONS: Anorectal physiology and colonic motility are similar between children with a history of TCS and children with FC, suggesting that the underlying pathophysiology of defecatory disorders in children with and without history of TCS is similar.


Assuntos
Canal Anal , Colo , Constipação Intestinal , Motilidade Gastrointestinal , Manometria , Defeitos do Tubo Neural , Reto , Humanos , Feminino , Estudos Retrospectivos , Manometria/métodos , Masculino , Criança , Constipação Intestinal/fisiopatologia , Constipação Intestinal/etiologia , Pré-Escolar , Defeitos do Tubo Neural/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Reto/fisiopatologia , Colo/fisiopatologia , Canal Anal/fisiopatologia , Estudos de Casos e Controles
12.
J Vis Exp ; (209)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39141536

RESUMO

Gastrointestinal diseases, which have a high incidence, pose considerable challenges for humans. The small intestine is integral to food and drug digestion and absorption and plays a crucial role in treating these diseases. The intestinal tube movement experiment, a common and essential in vitro method, is utilized to study gastrointestinal dynamics. This includes the preparation of the isolated intestinal tube, as well as the suspension of the prepared intestinal tube in the bath and its connection to a signal detector. This is followed by the recording and analysis of a series of parameters, such as tension, which can be used to assess intestinal motor function, as well as considerations for keeping the intestinal tube active in vitro. The standardized program from sampling to data collection greatly improves the repeatability of the experimental data and ensures the authenticity of the recording of intestinal tension after physiological, pathological, and drug intervention. Here we present the key problems in experimental operation and a valuable reference experimental protocol for studying drugs that regulate gastrointestinal motility.


Assuntos
Motilidade Gastrointestinal , Motilidade Gastrointestinal/fisiologia , Animais , Perfusão/métodos , Perfusão/instrumentação , Intestino Delgado/fisiologia , Ratos , Intestinos/fisiologia
13.
PLoS Pathog ; 20(8): e1011766, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39141685

RESUMO

Intestinal helminth infection triggers a type 2 immune response that promotes a 'weep-and sweep' response characterised by increased mucus secretion and intestinal hypermotility, which function to dislodge the worm from its intestinal habitat. Recent studies have discovered that several other pathogens cause intestinal dysmotility through major alterations to the immune and enteric nervous systems (ENS), and their interactions, within the gastrointestinal tract. However, the involvement of these systems has not been investigated for helminth infections. Eosinophils represent a key cell type recruited by the type 2 immune response and alter intestinal motility under steady-state conditions. Our study aimed to investigate whether altered intestinal motility driven by the murine hookworm, Nippostrongylus brasiliensis, infection involves eosinophils and how the ENS and smooth muscles of the gut are impacted. Eosinophil deficiency did not influence helminth-induced intestinal hypermotility and hypermotility did not involve gross structural or functional changes to the ENS. Hypermotility was instead associated with a dramatic increase in smooth muscle thickness and contractility, an observation that extended to another rodent nematode, Heligmosomoides polygyrus. In summary our data indicate that, in contrast to other pathogens, helminth-induced intestinal hypermotility is driven by largely by myogenic, rather than neurogenic, alterations with such changes occurring independently of eosinophils. (<300 words).


Assuntos
Sistema Nervoso Entérico , Eosinófilos , Motilidade Gastrointestinal , Músculo Liso , Nippostrongylus , Animais , Camundongos , Eosinófilos/imunologia , Músculo Liso/parasitologia , Sistema Nervoso Entérico/parasitologia , Sistema Nervoso Entérico/imunologia , Motilidade Gastrointestinal/fisiologia , Nematospiroides dubius/fisiologia , Nematospiroides dubius/imunologia , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Enteropatias Parasitárias/imunologia , Enteropatias Parasitárias/parasitologia , Helmintíase/imunologia , Helmintíase/parasitologia , Neurônios/parasitologia , Neurônios/metabolismo , Camundongos Endogâmicos C57BL
14.
Int J Circumpolar Health ; 83(1): 2392406, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39151145

RESUMO

Gastrointestinal function plays a pivotal role in nutrient absorption and overall digestive health. Abnormal gastric emptying is closely linked to type 2 diabetes, impacting blood glucose regulation and causing gastrointestinal symptoms. This study aims to investigate and compare segmental transit times, motility indices, and micromilieu between Greenlandic Inuit and Danish individuals with and without type 2 diabetes. We included forty-four Greenlandic Inuit, twenty-three of whom had type 2 diabetes, and age and gender-matched Danish individuals. Segmental transit time, motility, and luminal environment were measured using the SmartPill®. Greenlandic controls displayed shorter gastric emptying time (GET) (163 min), higher gastric median pH (2.0 pH) and duodenal median contractions (18.2 mm Hg) compared to Greenlanders with type 2 diabetes (GET: 235 min, pH:1.9, median duodenal contraction 18.4 mm Hg) and Danish controls (GET: 190, pH:1.2 median duodenal contraction 17.5 mmHg). Despite similar anti-diabetic management efforts, variations in gastrointestinal physiology were evident, highlighting the complexity of diabetes and its interaction with ethnicity, suggesting potential dietary or even genetic influences, emphasising the necessity for personalised diabetes management approaches. Finally, the study opens possibilities for future research, encouraging investigations into the underlying mechanisms linking genetics, diet, and gastric physiology, as an understanding of factors can lead to more effective, tailored strategies for diabetes care and improved digestive health in diverse populations.


Assuntos
Diabetes Mellitus Tipo 2 , Esvaziamento Gástrico , Motilidade Gastrointestinal , Inuíte , Humanos , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/fisiopatologia , Groenlândia/epidemiologia , Dinamarca/epidemiologia , Feminino , Masculino , Pessoa de Meia-Idade , Esvaziamento Gástrico/fisiologia , Motilidade Gastrointestinal/fisiologia , Adulto , Idoso , Duodeno
15.
Neurogastroenterol Motil ; 36(9): e14872, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39138548

RESUMO

BACKGROUND: Postoperative ileus (POI), characterized by absent gastrointestinal motility, is a frequent complication following major abdominal surgery, with no current effective treatment possibilities. For further research in the treatment of this condition, we aimed to establish a porcine model of POI. METHODS: A total of 12 Landrace pigs, weighing 60 kg, were included. Five animals were used as pilots to establish the surgical procedure, five animals received the same reproducible surgical procedure developed in the pilot experiments, while two animals were used as control. The primary endpoint was number of days to first stool. Intestinal motility was monitored using the SmartPill system. KEY RESULTS: Four of the five pigs who underwent the final surgical procedure passed first stool on the third postoperative day (POD), and one passed first stool on the fifth POD. SmartPill data showed retention of the capsule in the stomach in four of five pigs with usable traces. CONCLUSION AND INFERENCES: An experimental porcine model of POI was established, forming the basis for future studies in POI.


Assuntos
Modelos Animais de Doenças , Motilidade Gastrointestinal , Íleus , Complicações Pós-Operatórias , Animais , Íleus/etiologia , Suínos , Complicações Pós-Operatórias/etiologia , Motilidade Gastrointestinal/fisiologia
16.
J Surg Res ; 302: 186-199, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098117

RESUMO

BACKGROUND: Stomach, small intestine, and colon have distinct patterns of contraction related to their function to mix and propel enteric contents. In this study, we aim to measure gut myoelectric activity in the perioperative course using external patches in an animal model. METHODS: Four external patches were placed on the abdominal skin of female Yucatan pigs to record gastrointestinal myoelectric signals for 3 to 5 d. Pigs subsequently underwent anesthesia and placement of internal electrodes on stomach, small intestine, and colon. Signals were collected by a wireless transmitter. Frequencies associated with peristalsis were analyzed for both systems for 6 d postoperatively. RESULTS: In awake pigs, we found frequency peaks in several ranges, from 4 to 6.5 cycles per minute (CPM), 8 to 11 CPM, and 14 to 18 CPM, which were comparable between subjects and concordant between internal and external recordings. The possible effect of anesthesia during the 1 or 2 h before surgical manipulation was observed as a 59% (±36%) decrease in overall myoelectric activity compared to the immediate time before anesthesia. The myoelectrical activity recovered quickly postoperatively. Comparing the absolute postsurgery activity levels to the baseline for each pig revealed higher overall activity after surgery by a factor of 1.69 ± 0.3. CONCLUSIONS: External patch measurements correlated with internal electrode recordings. Anesthesia and surgery impacted gastrointestinal myoelectric activity. Recordings demonstrated a rebound phenomenon in myoelectric activity in the postoperative period. The ability to monitor gastrointestinal tract myoelectric activity noninvasively over multiple days could be a useful tool in diagnosing gastrointestinal motility disorders.


Assuntos
Tecnologia sem Fio , Animais , Feminino , Suínos , Tecnologia sem Fio/instrumentação , Motilidade Gastrointestinal/fisiologia , Modelos Animais , Eletromiografia/instrumentação , Eletromiografia/métodos , Peristaltismo/fisiologia , Estômago/fisiologia , Estômago/cirurgia , Colo/cirurgia , Colo/fisiologia , Período Perioperatório
17.
Comput Biol Med ; 181: 109035, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39213708

RESUMO

The stomach, a central organ in the Gastrointestinal (GI) tract, regulates the processing of ingested food through gastric motility and emptying. Understanding the stomach function is crucial for treating gastric disorders. Experimental studies in this field often face difficulties due to limitations and invasiveness of available techniques and ethical concerns. To counter this, researchers resort to computational and numerical methods. However, existing computational studies often isolate one aspect of the stomach function while neglecting the rest and employ computationally expensive methods. This paper proposes a novel cost-efficient multi-compartmental model, offering a comprehensive insight into gastric function at an organ level, thus presenting a promising alternative. The proposed approach divides the spatial geometry of the stomach into four compartments: Proximal/Middle/Terminal antrum and Pyloric sphincter. Each compartment is characterized by a set of ordinary differential equations (ODEs) with respect to time to characterize the stomach function. Electrophysiology is represented by simplified equations reflecting the "slow wave behavior" of Interstitial Cells of Cajal (ICC) and Smooth Muscle Cells (SMC) in the stomach wall. An electro-mechanical coupling model translates SMC "slow waves" into smooth muscle contractions. Muscle contractions induce peristalsis, affecting gastric fluid flow velocity and subsequent emptying when the pyloric sphincter is open. Contraction of the pyloric sphincter initiates a retrograde flow jet at the terminal antrum, modeled by a circular liquid jet flow equation. The results from the proposed model for a healthy human stomach were compared with experimental and computational studies on electrophysiology, muscle tissue mechanics, and fluid behavior during gastric emptying. These findings revealed that each "ICC" slow wave corresponded to a muscle contraction due to electro-mechanical coupling behavior. The rate of gastric emptying and mixing efficiency decreased with increasing viscosity of gastric liquid but remained relatively unchanged with gastric liquid density variations. Utilizing different ODE solvers in MATLAB, the model was solved, with ode15s demonstrating the fastest computation time, simulating 180 s of real-time stomach response in just 2.7 s. This multi-compartmental model signifies a promising advancement in understanding gastric function, providing a cost-effective and comprehensive approach to study complex interactions within the stomach and test innovative therapies like neuromodulation for treating gastric disorders.


Assuntos
Esvaziamento Gástrico , Modelos Biológicos , Estômago , Humanos , Esvaziamento Gástrico/fisiologia , Estômago/fisiologia , Músculo Liso/fisiologia , Contração Muscular/fisiologia , Motilidade Gastrointestinal/fisiologia , Células Intersticiais de Cajal/fisiologia , Simulação por Computador
18.
Exp Physiol ; 109(9): 1545-1556, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38979869

RESUMO

Gut motility undergoes a switch from myogenic to neurogenic control in late embryonic development. Here, we report on the electrical events that underlie this transition in the enteric nervous system, using the GCaMP6f reporter in neural crest cell derivatives. We found that spontaneous calcium activity is tetrodotoxin (TTX) resistant at stage E11.5, but not at E18.5. Motility at E18.5 was characterized by periodic, alternating high- and low-frequency contractions of the circular smooth muscle; this frequency modulation was inhibited by TTX. Calcium imaging at the neurogenic-motility stages E18.5-P3 showed that CaV1.2-positive neurons exhibited spontaneous calcium activity, which was inhibited by nicardipine and 2-aminoethoxydiphenyl borate (2-APB). Our protocol locally prevented muscle tone relaxation, arguing for a direct effect of nicardipine on enteric neurons, rather than indirectly by its relaxing effect on muscle. We demonstrated that the ENS was mechanosensitive from early stages on (E14.5) and that this behaviour was TTX and 2-APB resistant. We extended our results on L-type channel-dependent spontaneous activity and TTX-resistant mechanosensitivity to the adult colon. Our results shed light on the critical transition from myogenic to neurogenic motility in the developing gut, as well as on the intriguing pathways mediating electro-mechanical sensitivity in the enteric nervous system. HIGHLIGHTS: What is the central question of this study? What are the first neural electric events underlying the transition from myogenic to neurogenic motility in the developing gut, what channels do they depend on, and does the enteric nervous system already exhibit mechanosensitivity? What is the main finding and its importance? ENS calcium activity is sensitive to tetrodotoxin at stage E18.5 but not E11.5. Spontaneous electric activity at fetal and adult stages is crucially dependent on L-type calcium channels and IP3R receptors, and the enteric nervous system exhibits a tetrodotoxin-resistant mechanosensitive response. Abstract figure legend Tetrodotoxin-resistant Ca2+ rise induced by mechanical stimulation in the E18.5 mouse duodenum.


Assuntos
Canais de Cálcio Tipo L , Cálcio , Sistema Nervoso Entérico , Motilidade Gastrointestinal , Neurônios , Tetrodotoxina , Animais , Canais de Cálcio Tipo L/metabolismo , Tetrodotoxina/farmacologia , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/fisiologia , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Cálcio/metabolismo , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Músculo Liso/fisiologia , Camundongos Endogâmicos C57BL , Bloqueadores dos Canais de Cálcio/farmacologia , Feminino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Nicardipino/farmacologia , Compostos de Boro
19.
Cell Rep Med ; 5(7): 101646, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39019013

RESUMO

Bowel movement frequency (BMF) directly impacts the gut microbiota and is linked to diseases like chronic kidney disease or dementia. In particular, prior work has shown that constipation is associated with an ecosystem-wide switch from fiber fermentation and short-chain fatty acid production to more detrimental protein fermentation and toxin production. Here, we analyze multi-omic data from generally healthy adults to see how BMF affects their molecular phenotypes, in a pre-disease context. Results show differential abundances of gut microbial genera, blood metabolites, and variation in lifestyle factors across BMF categories. These differences relate to inflammation, heart health, liver function, and kidney function. Causal mediation analysis indicates that the association between lower BMF and reduced kidney function is partially mediated by the microbially derived toxin 3-indoxyl sulfate (3-IS). This result, in a generally healthy context, suggests that the accumulation of microbiota-derived toxins associated with abnormal BMF precede organ damage and may be drivers of chronic, aging-related diseases.


Assuntos
Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Indicã/sangue , Motilidade Gastrointestinal/fisiologia , Constipação Intestinal/sangue , Constipação Intestinal/microbiologia , Idoso
20.
JCI Insight ; 9(17)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042470

RESUMO

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.


Assuntos
Modelos Animais de Doenças , Sistema Nervoso Entérico , Motilidade Gastrointestinal , Doença de Hirschsprung , Camundongos Knockout , Células-Tronco Neurais , Animais , Doença de Hirschsprung/terapia , Doença de Hirschsprung/patologia , Células-Tronco Neurais/transplante , Motilidade Gastrointestinal/fisiologia , Camundongos , Sistema Nervoso Entérico/fisiopatologia , Colo/patologia , Receptor de Endotelina B/genética , Receptor de Endotelina B/metabolismo , Transplante de Células-Tronco/métodos , Movimento Celular , Feminino , Humanos , Masculino , Músculo Liso
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