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Dershowitz LB, Bueno Garcia H, Perley AS, Coleman TP, Kaltschmidt JA. Spontaneous enteric nervous system activity generates contractile patterns prior to maturation of gastrointestinal motility. Neurogastroenterol Motil 2024:e14890. [PMID: 39118231 DOI: 10.1111/nmo.14890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 06/09/2024] [Accepted: 07/29/2024] [Indexed: 08/10/2024]
Abstract
BACKGROUND Spontaneous neuronal network activity is essential to the functional maturation of central and peripheral circuits, yet whether this is a feature of enteric nervous system development has yet to be established. Although enteric neurons are known exhibit electrophysiological properties early in embryonic development, no connection has been drawn between this neuronal activity and the development of gastrointestinal (GI) motility patterns. METHODS We use ex vivo GI motility assays with newly developed unbiased computational analyses to identify GI motility patterns across mouse embryonic development. KEY RESULTS We find a previously unknown pattern of neurogenic contractions termed "clustered ripples" that arises spontaneously at embryonic day 16.5, an age earlier than any identified mature GI motility patterns. We further show that these contractions are driven by nicotinic cholinergic signaling. CONCLUSIONS & INFERENCES Clustered ripples are neurogenic contractile activity that arise from spontaneous ENS activity and precede all known forms of neurogenic GI motility. This earliest motility pattern requires nicotinic cholinergic signaling, which may inform pharmacology for enhancing GI motility in preterm infants.
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Affiliation(s)
- Lori B Dershowitz
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, USA
| | | | - Andrew S Perley
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Todd P Coleman
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, USA
- Department of Bioengineering, Stanford University, Stanford, California, USA
| | - Julia A Kaltschmidt
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, USA
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Hosie S, Abo-Shaban T, Mou K, Balasuriya GK, Mohsenipour M, Alamoudi MU, Filippone RT, Belz GT, Franks AE, Bornstein JC, Nurgali K, Hill-Yardin EL. Faster Gastrointestinal Transit, Reduced Small Intestinal Smooth Muscle Tone and Dysmotility in the Nlgn3R451C Mouse Model of Autism. Int J Mol Sci 2024; 25:832. [PMID: 38255906 PMCID: PMC10815490 DOI: 10.3390/ijms25020832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/18/2023] [Accepted: 12/12/2023] [Indexed: 01/24/2024] Open
Abstract
Individuals with autism often experience gastrointestinal issues but the cause is unknown. Many gene mutations that modify neuronal synapse function are associated with autism and therefore may impact the enteric nervous system that regulates gastrointestinal function. A missense mutation in the Nlgn3 gene encoding the cell adhesion protein Neuroligin-3 was identified in two brothers with autism who both experienced severe gastrointestinal dysfunction. Mice expressing this mutation (Nlgn3R451C mice) are a well-studied preclinical model of autism and show autism-relevant characteristics, including impaired social interaction and communication, as well as repetitive behaviour. We previously showed colonic dysmotility in response to GABAergic inhibition and increased myenteric neuronal numbers in the small intestine in Nlgn3R451C mice bred on a mixed genetic background. Here, we show that gut dysfunction is a persistent phenotype of the Nlgn3 R451C mutation in mice backcrossed onto a C57BL/6 background. We report that Nlgn3R451C mice show a 30.9% faster gastrointestinal transit (p = 0.0004) in vivo and have 6% longer small intestines (p = 0.04) compared to wild-types due to a reduction in smooth muscle tone. In Nlgn3R451C mice, we observed a decrease in resting jejunal diameter (proximal jejunum: 10.6% decrease, p = 0.02; mid: 9.8%, p = 0.04; distal: 11.5%, p = 0.009) and neurally regulated dysmotility as well as shorter durations of contractile complexes (mid: 25.6% reduction in duration, p = 0.009; distal: 30.5%, p = 0.004) in the ileum. In Nlgn3R451C mouse colons, short contractions were inhibited to a greater extent (57.2% by the GABAA antagonist, gabazine, compared to 40.6% in wild-type mice (p = 0.007). The inhibition of nitric oxide synthesis decreased the frequency of contractile complexes in the jejunum (WT p = 0.0006, Nlgn3R451C p = 0.002), but not the ileum, in both wild-type and Nlgn3R451C mice. These findings demonstrate that changes in enteric nervous system function contribute to gastrointestinal dysmotility in mice expressing the autism-associated R451C missense mutation in the Neuroligin-3 protein.
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Affiliation(s)
- Suzanne Hosie
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
| | - Tanya Abo-Shaban
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
| | - Kevin Mou
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
| | - Gayathri K. Balasuriya
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
- Graduate School of Medicine, Kobe University, Kobe 657-8501, Japan
| | - Mitra Mohsenipour
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
| | - Mohammed U. Alamoudi
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
- Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, Jazan University, Jazan 45142, Saudi Arabia
| | | | - Gabrielle T. Belz
- Frazer Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Ashley E. Franks
- Department of Microbiology, Anatomy, Physiology and Pharmacology, School of Life Sciences, La Trobe University, Melbourne, VIC 3083, Australia
| | - Joel C. Bornstein
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Kulmira Nurgali
- Institute for Health and Sport, Victoria University, Melbourne, VIC 3021, Australia
- Department of Medicine Western Health, University of Melbourne, Melbourne, VIC 3010, Australia
- Regenerative Medicine and Stem Cells Program, Australian Institute for Musculoskeletal Science (AIMSS), Melbourne, VIC 3021, Australia
| | - Elisa L. Hill-Yardin
- School of Health and Biomedical Sciences, STEM College, RMIT University, Melbourne, VIC 3083, Australia (T.A.-S.)
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
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Dershowitz LB, Garcia HB, Perley AS, Coleman TP, Kaltschmidt JA. Spontaneous enteric nervous system activity precedes maturation of gastrointestinal motility. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.03.551847. [PMID: 37577464 PMCID: PMC10418201 DOI: 10.1101/2023.08.03.551847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Spontaneous neuronal network activity is essential in development of central and peripheral circuits, yet whether this is a feature of enteric nervous system development has yet to be established. Using ex vivo gastrointestinal (GI) motility assays with unbiased computational analyses, we identify a previously unknown pattern of spontaneous neurogenic GI motility. We further show that this motility is driven by cholinergic signaling, which may inform GI pharmacology for preterm patients.
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Affiliation(s)
- Lori B. Dershowitz
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305 USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, 94305 USA
| | | | - Andrew S. Perley
- Department of Bioengineering, Stanford University, Stanford, CA, 94305 USA
| | - Todd P. Coleman
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, 94305 USA
- Department of Bioengineering, Stanford University, Stanford, CA, 94305 USA
| | - Julia A. Kaltschmidt
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305 USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, 94305 USA
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Sung TS, Ryoo SB, Lee CH, Choi SM, Nam JW, Kim HB, Lee JY, Lim JD, Park KJ, Lee HT. Prokinetic Activity of Mulberry Fruit, Morus alba L. Nutrients 2023; 15:nu15081889. [PMID: 37111108 PMCID: PMC10143206 DOI: 10.3390/nu15081889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/07/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
The fruit of Morus alba L. (MAF) has been consumed as a food worldwide. MAF has also been widely used in traditional medicine for thousands of years in East Asia, and its diverse bioactivities have been reported in numerous publications. However, no prokinetic activity has been reported for MAF or its components. In the present study, therefore, we investigated the effects of MAF on gastrointestinal motor function by measuring the intestinal transit rate (ITR) of Evans blue in mice in vivo. The ITR values accelerated by MAF were significantly higher than those accelerated by cisapride or metoclopramide, suggesting that MAF has potential as a new prokinetic agent to replace cisapride and metoclopramide. We also investigated the effects of MAF on myogenic and neurogenic contractions in human intestinal smooth muscles by measuring spontaneous contractions of smooth muscle strips, smooth muscle contractions induced by neural stimulation, and migrating motor complexes from intestinal segments in the human ileum and sigmoid colon in situ. MAF increased both myogenic and neurogenic contractions to enhance ileal and colonic motility in the human intestine. Taken together, these results indicate that MAF enhanced intestinal motility by increasing both myogenic and neurogenic contractions, thereby accelerating the ITR.
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Affiliation(s)
- Tae Sik Sung
- Department of Surgery, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Seung-Bum Ryoo
- Department of Surgery, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Chang-Hyun Lee
- Biopharmaceutical Engineering Major, Division of Applied Bioengineering, College of Engineering, Dong-Eui University, Busan 47340, Republic of Korea
| | - Seon-Min Choi
- Biopharmaceutical Engineering Major, Division of Applied Bioengineering, College of Engineering, Dong-Eui University, Busan 47340, Republic of Korea
| | - Joo-Won Nam
- College of Pharmacy, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Hyun-Bok Kim
- National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea
| | - Ji Young Lee
- Department of Ophthalmology and Visual Science, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul 06591, Republic of Korea
| | - Jung-Dae Lim
- Department of Herbal Medicine Resource, Kangwon National University, Samcheok 25949, Republic of Korea
| | - Kyu Joo Park
- Department of Surgery, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Hyun-Tai Lee
- Biopharmaceutical Engineering Major, Division of Applied Bioengineering, College of Engineering, Dong-Eui University, Busan 47340, Republic of Korea
- Core-Facility Center for Tissue Regeneration, Dong-Eui University, Busan 47340, Republic of Korea
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Miller KJW, Cheng LK, Angeli-Gordon TR, Avci R, Paskaranandavadivel N. The bioelectrical conduction system around the ileocecal junction defined through in vivo high-resolution mapping in rabbits. Am J Physiol Gastrointest Liver Physiol 2022; 323:G318-G330. [PMID: 35916409 DOI: 10.1152/ajpgi.00329.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Coordinated contractions across the small and large intestines via the ileocecal junction (ICJ) are critical to healthy gastrointestinal function and are in part governed by myoelectrical activity. In this study, the spatiotemporal characteristics of the bioelectrical conduction across the ICJ and its adjacent regions were quantified in anesthetized rabbits. High-resolution mapping was applied from the terminal ileum (TI) to the sacculus rotundus (SR), across the ICJ and into the beginning of the large intestine at the cecum ampulla coli (AC). Orally propagating slow wave patterns in the SR did not entrain the TI. However, aborally propagating patterns from the TI were able to entrain the SR. Bioelectrical activity was recorded within the ICJ and AC, revealing complex interactions of slow waves, spike bursts, and bioelectrical quiescence. This suggests the involvement of myogenic coordination when regulating motility between the small and large intestines. Mean slow wave frequency between regions did not vary significantly (13.74-17.16 cycles/min). Slow waves in the SR propagated with significantly faster speeds (18.51 ± 1.57 mm/s) compared with the TI (14.05 ± 2.53 mm/s, P = 0.0113) and AC (9.56 ± 1.56 mm/s, P = 0.0001). Significantly higher amplitudes were observed in both the TI (0.28 ± 0.13 mV, P = 0.0167) and SR (0.24 ± 0.08 mV, P = 0.0159) within the small intestine compared with the large intestine AC (0.03 ± 0.01 mV). We hypothesize that orally propagating slow waves facilitate a motor-brake pattern in the SR to limit outflow into the ICJ, similar to those previously observed in other gastrointestinal regions.NEW & NOTEWORTHY Competing slow wave pacemakers were observed in the terminal ileum and sacculus rotundus. Prevalent oral propagation in the sacculus rotundus toward the terminal ileum potentially acts as a brake mechanism limiting outflow. Slow waves and periods of quiescence at the ileocecal junction suggest that activation may depend on the coregulatory flow and distention pathways. Slow waves and spike bursts in the cecum impart a role in the coordination of motility.
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Affiliation(s)
- Kiara J W Miller
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Leo K Cheng
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.,Riddet Institute, Palmerston North, New Zealand
| | - Timothy R Angeli-Gordon
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.,Riddet Institute, Palmerston North, New Zealand
| | - Recep Avci
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
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Feng J, Hibberd TJ, Luo J, Yang P, Xie Z, Travis L, Spencer NJ, Hu H. Modification of Neurogenic Colonic Motor Behaviours by Chemogenetic Ablation of Calretinin Neurons. Front Cell Neurosci 2022; 16:799717. [PMID: 35317196 PMCID: PMC8934436 DOI: 10.3389/fncel.2022.799717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/31/2022] [Indexed: 12/31/2022] Open
Abstract
How the enteric nervous system determines the pacing and propagation direction of neurogenic contractions along the colon remains largely unknown. We used a chemogenetic strategy to ablate enteric neurons expressing calretinin (CAL). Mice expressing human diphtheria toxin receptor (DTR) in CAL neurons were generated by crossing CAL-ires-Cre mice with Cre-dependent ROSA26-DTR mice. Immunohistochemical analysis revealed treatment with diphtheria toxin incurred a 42% reduction in counts of Hu-expressing colonic myenteric neurons (P = 0.036), and 57% loss of CAL neurons (comprising ∼25% of all Hu neurons; P = 0.004) compared to control. As proportions of Hu-expressing neurons, CAL neurons that contained nitric oxide synthase (NOS) were relatively spared (control: 15 ± 2%, CAL-DTR: 13 ± 1%; P = 0.145), while calretinin neurons lacking NOS were significantly reduced (control: 26 ± 2%, CAL-DTR: 18 ± 5%; P = 0.010). Colonic length and pellet sizes were significantly reduced without overt inflammation or changes in ganglionic density. Interestingly, colonic motor complexes (CMCs) persisted with increased frequency (mid-colon interval 111 ± 19 vs. 189 ± 24 s, CAL-DTR vs. control, respectively, P < 0.001), decreased contraction size (mid-colon AUC 26 ± 24 vs. 59 ± 13 gram/seconds, CAL-DTR vs. control, respectively, P < 0.001), and lacked preferential anterograde migration (P < 0.001). The functional effects of modest calretinin neuron ablation, particularly increased neurogenic motor activity frequencies, differ from models that incur general enteric neuron loss, and suggest calretinin neurons may contribute to pacing, force, and polarity of CMCs in the large bowel.
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Affiliation(s)
- Jing Feng
- Center for the Study of Itch and Sensory Disorders, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Center for Neurological and Psychiatric Research and Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Tim J. Hibberd
- College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Adelaide, SA, Australia
| | - Jialie Luo
- Center for the Study of Itch and Sensory Disorders, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Pu Yang
- Center for the Study of Itch and Sensory Disorders, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Zili Xie
- Center for the Study of Itch and Sensory Disorders, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
| | - Lee Travis
- College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Adelaide, SA, Australia
| | - Nick J. Spencer
- College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Adelaide, SA, Australia
- *Correspondence: Nick J. Spencer,
| | - Hongzhen Hu
- Center for the Study of Itch and Sensory Disorders, Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO, United States
- Hongzhen Hu,
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Spencer NJ, Costa M. Rhythmicity in the Enteric Nervous System of Mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1383:295-306. [PMID: 36587167 DOI: 10.1007/978-3-031-05843-1_27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The enteric nervous system (ENS) is required for many cyclical patterns of motor activity along different regions of the gastrointestinal (GI) tract. What has remained mysterious is precisely how many thousands of neurons within the ENS are temporally activated to generate cyclical neurogenic contractions of GI-smooth muscle layers. This has been an especially puzzling conundrum, since the ENS consists of an extensive network of small ganglia, with each ganglion consisting of a heterogeneous population of neurons, with diverse cell soma morphologies, neurochemical and biophysical characteristics, and neural connectivity. Neuronal imaging studies of the mouse large intestine have provided major new insights into how the different classes of myenteric neurons are activated during cyclical neurogenic motor patterns, such as the colonic motor complex (CMC). It has been revealed that during CMCs (in the isolated mouse whole colon), large populations of myenteric neurons, across large spatial fields, coordinate their firing, via bursts of fast synaptic inputs at ~2 Hz. This coordinated firing of many thousands of myenteric neurons synchronously over many rows of interconnected ganglia occurs irrespective of the functional class of neuron. Aborally directed propulsion of content along the mouse colon is due, in large part, to polarity of the enteric circuits including the projections of the intrinsic excitatory and inhibitory motor neurons but still involves the fundamental ~2 Hz rhythmic activity of specific classes of enteric neurons. What remains to be determined are the mechanisms that initiate and terminate the patterned firing of large ensembles of enteric neurons during cyclic activity. This remains an exciting challenge for future studies.
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Affiliation(s)
- Nick J Spencer
- Visceral Neurophysiology Laboratory, Department of Physiology, College of Medicine and Public Health & Centre for Neuroscience, Flinders University, Bedford Park, SA, Australia.
| | - Marcello Costa
- Visceral Neurophysiology Laboratory, Department of Physiology, College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia
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Costa M, Wiklendt L, Hibberd T, Dinning P, Spencer NJ, Brookes S. Analysis of Intestinal Movements with Spatiotemporal Maps: Beyond Anatomy and Physiology. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1383:271-294. [PMID: 36587166 DOI: 10.1007/978-3-031-05843-1_26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Over 150 years ago, methods for quantitative analysis of gastrointestinal motor patterns first appeared. Graphic representations of physiological variables were recorded with the kymograph after the mid-1800s. Changes in force or length of intestinal muscles could be quantified, however most recordings were limited to a single point along the digestive tract.In parallel, photography and cinematography with X-Rays visualised changes in intestinal shape, but were hard to quantify. More recently, the ability to record physiological events at many sites along the gut in combination with computer processing allowed construction of spatiotemporal maps. These included diameter maps (DMaps), constructed from video recordings of intestinal movements and pressure maps (PMaps), constructed using data from high-resolution manometry catheters. Combining different kinds of spatiotemporal maps revealed additional details about gut wall status, including compliance, which relates forces to changes in length. Plotting compliance values along the intestine enabled combined DPMaps to be constructed, which can distinguish active contractions and relaxations from passive changes. From combinations of spatiotemporal maps, it is possible to deduce the role of enteric circuits and pacemaker cells in the generation of complex motor patterns. Development and application of spatiotemporal methods to normal and abnormal motor patterns in animals and humans is ongoing, with further technical improvements arising from their combination with impedance manometry, magnetic resonance imaging, electrophysiology, and ultrasonography.
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Affiliation(s)
- Marcello Costa
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia.
| | - Luke Wiklendt
- Department of Gastroenterology and Surgery, Flinders Medical Centre, Bedford Park, SA, Australia
| | - Tim Hibberd
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
| | - Phil Dinning
- Department of Gastroenterology and Surgery, Flinders Medical Centre, Bedford Park, SA, Australia
| | - Nick J Spencer
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
| | - Simon Brookes
- College of Medicine and Public Health, Department of Human Physiology, Flinders University, Bedford Park, SA, Australia
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Kuruppu S, Cheng LK, Nielsen PMF, Gamage TPB, Avci R, Angeli TR, Paskaranandavadivel N. High-Resolution Spatiotemporal Quantification of Intestinal Motility with Free-Form Deformation. IEEE Trans Biomed Eng 2021; 69:2077-2086. [PMID: 34910629 DOI: 10.1109/tbme.2021.3135855] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To develop a method to quantify strain fields from in vivo intestinal motility recordings that mitigate accumulation of tracking error. METHODS The deforming geometry of the intestine in video sequences was modeled by a biquadratic B-spline mesh. Green-Lagrange strain fields were computed to quantify the surface deformations from motility. A nonlinear optimization scheme was applied to mitigate the accumulation of tracking error associated with image registration. RESULTS The optimization scheme maintained the RMS strain error under 1% and reduced the rate of strain error by 97% during synthetic tests. The algorithm was applied to map 64 segmental, 12 longitudinal, and 23 propagating circular contractions in the jejunum. Coordinated activity of the two muscle layers could be identified and the strain fields were able to map and quantify the anisotropic contractions of the intestine. Frequency and velocity were also quantified, from which two types of propagating circular contractions were identified: (i) -0:360:04 strain contractions that originated spontaneously and propagated at 31 mm/s in two pigs, and (ii) cyclic propagating contractions of -0:170:02 strain occurred at 11:00:6 cpm and propagated at 164 mm/s in a rabbit. CONCLUSION The algorithm simultaneously mapped the circular, longitudinal activity of the intestine with high spatial resolution and quantified anisotropic contractions and relaxations. SIGNIFICANCE The proposed algorithm can now be used to define the interactions of muscle layers during motility patterns. It can be integrated with high-resolution bioelectrical recordings to investigate the regulatory mechanisms of motility.
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Wood JD. Motor behavior of mouse large intestine: A Minireview. Neurogastroenterol Motil 2021; 33:e14206. [PMID: 34145934 DOI: 10.1111/nmo.14206] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/03/2021] [Accepted: 06/03/2021] [Indexed: 01/02/2023]
Abstract
Mice with a recessive gene which reduces the number of ganglion cells of the distal colon and rectum and produces megacolon, imitating Hirschsprung disease, are discussed as a model for integrative control of the large intestinal smooth musculature by the enteric division of the autonomic nervous system (ie, the brain-in-the-gut). Investigative approaches, such as propulsion of artificial pellets in preparations of whole colon in organ baths in vitro and innovative approaches capitalizing on neurogenetic technologies (eg, optogenetics), are considered in view of potential application in the development of novel therapeutic mechanisms to selectively evoke and control gastrointestinal motility patterns, such as the small intestinal digestive motility pattern, interdigestive pattern, and reversed direction of powerful propulsive motility during emesis. This minireview relates to the paper titled: "Motor patterns in the proximal and distal mouse colon which underlie formation and propulsion of feces," appearing in this issue of Neurogastroenterology and Motility.
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Affiliation(s)
- Jackie Dale Wood
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH, USA
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Costa M, Keightley LJ, Hibberd TJ, Wiklendt L, Smolilo DJ, Dinning PG, Brookes SJ, Spencer NJ. Characterization of alternating neurogenic motor patterns in mouse colon. Neurogastroenterol Motil 2021; 33:e14047. [PMID: 33252184 DOI: 10.1111/nmo.14047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/28/2020] [Accepted: 11/06/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Colonic motor complexes (CMCs) have been widely recorded in the large intestine of vertebrates. We have investigated whether in the smooth muscle, a single unified pattern of electrical activity, or different patterns of electrical activity give rise to the different neurogenic patterns of motility underlying CMCs in vitro. METHODS To study differences of the CMCs between proximal and distal colon, we used a novel combination of techniques to simultaneously record muscle diameter and force at multiple sites along the whole mouse colon ex vivo. In addition, electrical activity of smooth muscle was recorded by suction electrodes. KEY RESULTS Two distinct types of CMCs were distinguished; CMCs that propagated along the entire colon (complete CMC) and CMCs which were restricted to the proximal colon (incomplete CMC). The two types of CMC often occurred in the same preparations. Incomplete CMCs had longer bursts of smooth muscle action potentials than complete CMCs and propagated more slowly. Interestingly, both types of CMC were associated with similar frequency bursts of smooth muscle action potentials at ~2.4 Hz. In the most proximal colon, an additional firing frequency was detected close to ~7 Hz generating multiple peaks within each CMC. CONCLUSIONS & INFERENCES We report distinct characteristics underlying complete and incomplete CMCs in isolated mouse colon. Recognizing these distinct patterns of motility will be important for future interpretation of analysis of murine colonic motility recordings. The identification of alternating patterns of motor activity in proximal colon, but not distal colon may reflect specific neural mechanisms for fecal pellet formation.
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Affiliation(s)
- Marcello Costa
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Lauren J Keightley
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Timothy J Hibberd
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Lukasz Wiklendt
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - David J Smolilo
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Phil G Dinning
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Simon J Brookes
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Nick J Spencer
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
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Spencer NJ, Costa M, Hibberd TJ, Wood JD. Advances in colonic motor complexes in mice. Am J Physiol Gastrointest Liver Physiol 2021; 320:G12-G29. [PMID: 33085903 DOI: 10.1152/ajpgi.00317.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The primary functions of the gastrointestinal (GI) tract are to absorb nutrients, water, and electrolytes that are essential for life. This is accompanied by the capability of the GI tract to mix ingested content to maximize absorption and effectively excrete waste material. There have been major advances in understanding intrinsic neural mechanisms involved in GI motility. This review highlights major advances over the past few decades in our understanding of colonic motor complexes (CMCs), the major intrinsic neural patterns that control GI motility. CMCs are generated by rhythmic coordinated firing of large populations of myenteric neurons. Initially, it was thought that serotonin release from the mucosa was required for CMC generation. However, careful experiments have now shown that neither the mucosa nor endogenous serotonin are required, although, evidence suggests enteroendocrine (EC) cells modulate CMCs. The frequency and extent of propagation of CMCs are highly dependent on mechanical stimuli (circumferential stretch). In summary, the isolated mouse colon emerges as a good model to investigate intrinsic mechanisms underlying colonic motility and provides an excellent preparation to explore potential therapeutic agents on colonic motility, in a highly controlled in vitro environment. In addition, during CMCs, the mouse colon facilitates investigations into the emergence of dynamic assemblies of extensive neural networks, applicable to the nervous system of different organisms.
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Affiliation(s)
- N J Spencer
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - M Costa
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - T J Hibberd
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - J D Wood
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, Ohio
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Spencer NJ, Travis L, Wiklendt L, Hibberd TJ, Costa M, Dinning P, Hu H. Diversity of neurogenic smooth muscle electrical rhythmicity in mouse proximal colon. Am J Physiol Gastrointest Liver Physiol 2020; 318:G244-G253. [PMID: 31790272 DOI: 10.1152/ajpgi.00317.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The mechanisms underlying electrical rhythmicity in smooth muscle of the proximal colon are incompletely understood. Our aim was to identify patterns of electrical rhythmicity in smooth muscle of the proximal region of isolated whole mouse colon and characterize their mechanisms of origin. Two independent extracellular recording electrodes were used to record the patterns of electrical activity in smooth muscle of the proximal region of whole isolated mouse colon. Cross-correlation analysis was used to quantify spatial coordination of these electrical activities over increasing electrode separation distances. Four distinct neurogenic patterns of electrical rhythmicity were identified in smooth muscle of the proximal colon, three of which have not been identified and consisted of bursts of rhythmic action potentials at 1-2 Hz that were abolished by hexamethonium. These neurogenic patterns of electrical rhythmicity in smooth muscle were spatially and temporally synchronized over large separation distances (≥2 mm rosto-caudal axis). Myogenic slow waves could be recorded from the same preparations, but they showed poor spatial and temporal coordination over even short distances (≤1 mm rostro-caudal axis). It is not commonly thought that electrical rhythmicity in gastrointestinal smooth muscle is dependent upon the enteric nervous system. Here, we identified neurogenic patterns of electrical rhythmicity in smooth muscle of the proximal region of isolated mouse colon, which are dependent on synaptic transmission in the enteric nervous system. If the whole colon is studied in vitro, recordings can preserve novel neurogenic patterns of electrical rhythmicity in smooth muscle.NEW & NOTEWORTHY Previously, it has not often been thought that electrical rhythmicity in smooth muscle of the gastrointestinal tract is dependent upon the enteric nervous system. We identified patterns of electrical rhythmicity in smooth muscle of the mouse proximal colon that were abolished by hexamethonium and involved the temporal synchronization of smooth muscle membrane potential over large spatial fields. We reveal different patterns of electrical rhythmicity in colonic smooth muscle that are dependent on the ENS.
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Affiliation(s)
- Nick J Spencer
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - Lee Travis
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - Lukasz Wiklendt
- Department of Gastroenterology, Flinders Medical Center, Bedford Park, South Australia, Australia
| | - Timothy J Hibberd
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - Marcello Costa
- Visceral Neurophysiology Laboratory, College of Medicine and Public Health, Centre for Neuroscience, Flinders University, Bedford Park, South Australia, Australia
| | - Phil Dinning
- Department of Gastroenterology, Flinders Medical Center, Bedford Park, South Australia, Australia
| | - Hongzhen Hu
- Department of Anesthesiology, Center for the Study of Itch, Washington University, St. Louis, Missouri
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