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Hayashi T, Kanno SI, Watanabe C, Scuteri D, Agatsuma Y, Hara A, Bagetta G, Sakurada T, Sakurada S. Role of Spinal Cholecystokinin Octapeptide, Nociceptin/Orphanin FQ, and Hemokinin-1 in Diabetic Allodynia. Biomedicines 2024; 12:1332. [PMID: 38927539 PMCID: PMC11202074 DOI: 10.3390/biomedicines12061332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 06/12/2024] [Accepted: 06/14/2024] [Indexed: 06/28/2024] Open
Abstract
A complication of diabetes is neuropathic pain, which is difficult to control with medication. We have confirmed that neuropathic pain due to mechanical allodynia in diabetic mice is mediated by a characteristic neuropeptide in the spinal cord. We evaluated the strength of mechanical allodynia in mice using von Frey filaments. When mice were intravenously injected with streptozotocin, mechanical allodynia appeared 3 days later. Antibodies of representative neuropeptides were intrathecally (i.t.) administered to allodynia-induced mice 7 days after the intravenous administration of streptozotocin, and allodynia was reduced by anti-cholecystokinin octapeptide antibodies, anti-nociceptin/orphanin FQ antibodies, and anti-hemokinin-1 antibodies. In contrast, i.t.-administered anti-substance P antibodies, anti-somatostatin antibodies, and anti-angiotensin II antibodies did not affect streptozotocin-induced diabetic allodynia mice. Mechanical allodynia was attenuated by the i.t. administration of CCK-B receptor antagonists and ORL-1 receptor antagonists. The mRNA level of CCK-B receptors in streptozotocin-induced diabetic allodynia mice increased in the spinal cord, but not in the dorsal root ganglion. These results indicate that diabetic allodynia is caused by cholecystokinin octapeptide, nociceptin/orphanin FQ, and hemokinin-1 released from primary afferent neurons in the spinal cord that transmit pain to the brain via the spinal dorsal horn.
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Affiliation(s)
- Takafumi Hayashi
- Division of Pharmaceutics, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan; (T.H.); (Y.A.)
| | - Syu-ichi Kanno
- Division of Clinical Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan; (S.-i.K.); (A.H.)
| | - Chizuko Watanabe
- Division of Physiology and Anatomy, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan;
| | - Damiana Scuteri
- Department of Health Sciences, University “Magna Graecia” of Catanzaro, 88100 Catanzaro, Italy;
| | - Yasuyuki Agatsuma
- Division of Pharmaceutics, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan; (T.H.); (Y.A.)
| | - Akiyoshi Hara
- Division of Clinical Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan; (S.-i.K.); (A.H.)
| | - Giacinto Bagetta
- Pharmacotechnology Documentation & Transfer Unit, Department of Pharmacy, Preclinical & Translational Pharmacology, Health & Nutritional Sciences, University of Calabria, 87036 Rende, Italy;
| | - Tsukasa Sakurada
- Faculty of Pharmacy, Daiichi University of Pharmacy, Fukuoka 815-8511, Japan;
| | - Shinobu Sakurada
- Faculty of Pharmaceutical Sciences, Tohoku Medical and Pharmaceutical University, Sendai 981-8558, Japan
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Li S, Liu M, Cao S, Liu B, Li D, Wang Z, Sun H, Cui Y, Shi Y. The Mechanism of the Gut-Brain Axis in Regulating Food Intake. Nutrients 2023; 15:3728. [PMID: 37686760 PMCID: PMC10490484 DOI: 10.3390/nu15173728] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 08/16/2023] [Accepted: 08/23/2023] [Indexed: 09/10/2023] Open
Abstract
With the increasing prevalence of energy metabolism disorders such as diabetes, cardiovascular disease, obesity, and anorexia, the regulation of feeding has become the focus of global attention. The gastrointestinal tract is not only the site of food digestion and absorption but also contains a variety of appetite-regulating signals such as gut-brain peptides, short-chain fatty acids (SCFAs), bile acids (BAs), bacterial proteins, and cellular components produced by gut microbes. While the central nervous system (CNS), as the core of appetite regulation, can receive and integrate these appetite signals and send instructions to downstream effector organs to promote or inhibit the body's feeding behaviour. This review will focus on the gut-brain axis mechanism of feeding behaviour, discussing how the peripheral appetite signal is sensed by the CNS via the gut-brain axis and the role of the central "first order neural nuclei" in the process of appetite regulation. Here, elucidation of the gut-brain axis mechanism of feeding regulation may provide new strategies for future production practises and the treatment of diseases such as anorexia and obesity.
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Affiliation(s)
- Shouren Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
| | - Mengqi Liu
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
| | - Shixi Cao
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
| | - Boshuai Liu
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
| | - Defeng Li
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
| | - Zhichang Wang
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
| | - Hao Sun
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
| | - Yalei Cui
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
| | - Yinghua Shi
- College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China; (S.L.); (M.L.)
- Henan Key Laboratory of Innovation and Utilization of Grassland Resources, Zhengzhou 450002, China
- Henan Forage Engineering Technology Research Center, Zhengzhou 450002, China
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Xiang T, Li JH, Su HY, Bai KH, Wang S, Traub RJ, Cao DY. Spinal CCK1 Receptors Contribute to Somatic Pain Hypersensitivity Induced by Malocclusion via a Reciprocal Neuron-Glial Signaling Cascade. THE JOURNAL OF PAIN 2022; 23:1629-1645. [PMID: 35691467 PMCID: PMC9560966 DOI: 10.1016/j.jpain.2022.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 05/05/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
Recent studies have shown that the incidence of chronic primary pain including temporomandibular disorders (TMD) and fibromyalgia syndrome (FMS) often exhibit comorbidities. We recently reported that central sensitization and descending facilitation system contributed to the development of somatic pain hypersensitivity induced by orofacial inflammation combined with stress. The purpose of this study was to explore whether TMD caused by unilateral anterior crossbite (UAC) can induce somatic pain hypersensitivity, and whether the cholecystokinin (CCK) receptor-mediated descending facilitation system promotes hypersensitivity through neuron-glia cell signaling cascade. UAC evoked thermal and mechanical pain hypersensitivity of the hind paws from day 5 to 70 that peaked at week 4 post UAC. The expression levels of CCK1 receptors, interleukin-18 (IL-18) and IL-18 receptors (IL-18R) were significantly up-regulated in the L4 to L5 spinal dorsal horn at 4 weeks post UAC. Intrathecal injection of CCK1 and IL-18 receptor antagonists blocked somatic pain hypersensitivity. IL-18 mainly co-localized with microglia, while IL-18R mainly co-localized with astrocytes and to a lesser extent with neurons. These findings indicate that the signaling transduction between neurons and glia at the spinal cord level contributes to the descending pain facilitation through CCK1 receptors during the development of the comorbidity of TMD and FMS. PERSPECTIVE: CCK1 receptor-dependent descending facilitation may mediate central mechanisms underlying the development of widespread somatic pain via a reciprocal neuron-glial signaling cascade, providing novel therapeutic targets for the clinical treatment of TMD and FMS comorbidities.
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Affiliation(s)
- Ting Xiang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Research Center of Stomatology, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China; Department of Orthodontics, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China
| | - Jia-Heng Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Research Center of Stomatology, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China
| | - Han-Yu Su
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Research Center of Stomatology, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China
| | - Kun-Hong Bai
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Research Center of Stomatology, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China
| | - Shuang Wang
- Department of Orthodontics, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China
| | - Richard J Traub
- Department of Neural and Pain Sciences, School of Dentistry; Center to Advance Chronic Pain Research, University of Maryland Baltimore, Baltimore, Maryland.
| | - Dong-Yuan Cao
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, Research Center of Stomatology, Xi'an Jiaotong University College of Stomatology, Xi'an, Shaanxi, China.
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Li Y, Cui ZJ. Transmembrane Domain 3 Is a Transplantable Pharmacophore in the Photodynamic Activation of Cholecystokinin 1 Receptor. ACS Pharmacol Transl Sci 2022; 5:539-547. [PMID: 35983279 PMCID: PMC9379944 DOI: 10.1021/acsptsci.2c00031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cholecystokinin 1 receptor (CCK1R) is activated in photodynamic action by singlet oxygen, but detailed molecular mechanisms are not elucidated. To identify the pharmacophore(s) in photodynamic CCK1R activation, we examined photodynamic activation of point mutants CCK1RM121/3.32A, CCK1RM121/3.32Q, and a chimeric receptor with CCK1R transmembrane domain 3 (TM3) transplanted to muscarinic ACh receptor 3 (M3R) which is unaffected by photodynamic action. These engineered receptors were tagged at the N-terminus with genetically encoded protein photosensitizer miniSOG, and their light-driven photodynamic activation was compared to wild type CCK1R and M3R, as monitored by Fura-2 fluorescent calcium imaging. Photodynamic activations of miniSOG-CCK1RM121/3.32A and miniSOG-CCK1RM121/3.32Q were found to be 55% and 73%, respectively, when compared to miniSOG-CCK1R (100%), whereas miniSOG-M3R was not affected (0% activation). Notably, the chimeric receptor miniSOG-M3R-TM3CCK1R was effectively activated photodynamically (65%). These data suggest that TM3 is an important pharmacophore in photodynamic CCK1R activation, readily transplantable to nonsusceptible M3R for photodynamic activation.
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Affiliation(s)
- Yuan Li
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China
| | - Zong Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China
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Wachsmuth HR, Weninger SN, Duca FA. Role of the gut-brain axis in energy and glucose metabolism. Exp Mol Med 2022; 54:377-392. [PMID: 35474341 PMCID: PMC9076644 DOI: 10.1038/s12276-021-00677-w] [Citation(s) in RCA: 67] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 07/01/2021] [Accepted: 07/08/2021] [Indexed: 12/12/2022] Open
Abstract
The gastrointestinal tract plays a role in the development and treatment of metabolic diseases. During a meal, the gut provides crucial information to the brain regarding incoming nutrients to allow proper maintenance of energy and glucose homeostasis. This gut-brain communication is regulated by various peptides or hormones that are secreted from the gut in response to nutrients; these signaling molecules can enter the circulation and act directly on the brain, or they can act indirectly via paracrine action on local vagal and spinal afferent neurons that innervate the gut. In addition, the enteric nervous system can act as a relay from the gut to the brain. The current review will outline the different gut-brain signaling mechanisms that contribute to metabolic homeostasis, highlighting the recent advances in understanding these complex hormonal and neural pathways. Furthermore, the impact of the gut microbiota on various components of the gut-brain axis that regulates energy and glucose homeostasis will be discussed. A better understanding of the gut-brain axis and its complex relationship with the gut microbiome is crucial for the development of successful pharmacological therapies to combat obesity and diabetes.
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Affiliation(s)
| | | | - Frank A Duca
- School of Animal and Comparative Biomedical Sciences, College of Agricultural and Life Sciences, University of Arizona, Tucson, AZ, USA. .,BIO5, University of Arizona, Tucson, AZ, USA.
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Vana V, Laerke MK, Rehfeld JF, Arnold M, Dmytriyeva O, Langhans W, Schwartz TW, Hansen HS. Vagal afferent cholecystokinin receptor activation is required for glucagon-like peptide-1-induced satiation. Diabetes Obes Metab 2022; 24:268-280. [PMID: 34658116 DOI: 10.1111/dom.14575] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/27/2021] [Accepted: 10/08/2021] [Indexed: 12/31/2022]
Abstract
Peripheral glucagon-like peptide-1 (GLP-1) and cholecystokinin (CCK) are secreted from enteroendocrine cells, and their plasma concentrations increase in response to eating. While the satiating effect of gut-derived CCK on food-intake control is well documented, the effect of peripheral GLP-1 is less clear. There is evidence that native GLP-1 can inhibit food intake only in the fed state but not in the fasting state. We therefore hypothesized that other gut peptides released during a meal might influence the subsequent effect of endogenous GLP-1 and investigated whether CCK could do so. We found that intraperitoneal injection of CCK in food-restricted mice inhibited food intake during the first 30-minute segment of a 1-hour session of ad libitum chow intake and that mice compensated by increasing their intake during the second half of the session. Importantly, this compensatory behaviour was abolished by an intraperitoneal injection of GLP-1 administered following an intraperitoneal injection of CCK and prior to the 1-hour session. In vivo activation of the free fatty acid 1 (FFA1) receptor with orally administered TAK875 increased plasma CCK concentration and, consistent with the effect of exogenous CCK, we found that prior oral administration of TAK875 increased the eating inhibitory effect of peripherally administered GLP-1. To examine the role of the vagus nerve in this effect, we utilized a saporin-based lesioning procedure to selectively ablate the CCK receptor-expressing gastrointestinal vagal afferent neurones (VANs). We found that the combined anorectic effect of TAK875 and GLP-1 was significantly attenuated in the absence of CCK receptor expressing VANs. Taken together, our results indicate that endogenous CCK interacts with GLP-1 to promote satiation and that activation of the FFA1 receptor can initiate this interaction by stimulating the release of CCK.
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Affiliation(s)
- Vasiliki Vana
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Michelle K Laerke
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens F Rehfeld
- Department of Clinical Biochemistry (KB3011), Rigshospitalet, Copenhagen, Denmark
| | - Myrtha Arnold
- Physiology and Behavior Laboratory, Department of Health Sciences and Technology, ETH Zurich, Schwerzenbach, Switzerland
| | - Oksana Dmytriyeva
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, Department of Health Sciences and Technology, ETH Zurich, Schwerzenbach, Switzerland
| | - Thue W Schwartz
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Harald S Hansen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Long Acellular Nerve Allografts Cap Transected Nerve to Arrest Axon Regeneration and Alter Upstream Gene Expression in a Rat Neuroma Model. Plast Reconstr Surg 2021; 148:32e-41e. [PMID: 34014904 DOI: 10.1097/prs.0000000000008051] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Treatments to manage painful neuroma are needed. An operative strategy that isolates and controls chaotic axonal growth could prevent neuroma. Using long acellular nerve allograft to "cap" damaged nerve could control axonal regeneration and, in turn, regulate upstream gene expression patterns. METHODS Rat sciatic nerve was transected, and the distal nerve end was reversed and ligated to generate a model end-neuroma. Three groups were used to assess their effects immediately following this nerve injury: no treatment (control), traction neurectomy, or 5-cm acellular nerve allograft cap attached to the proximal nerve. Regeneration of axons from the injured nerve was assessed over 5 months and paired with concurrent measurements of gene expression from upstream affected dorsal root ganglia. RESULTS Both control and traction neurectomy groups demonstrated uncontrolled axon regeneration revealed using Thy1-GFP rat axon imaging and histomorphometric measures of regenerated axons within the most terminal region of regenerated tissue. The acellular nerve allograft group arrested axons within the acellular nerve allograft, where no axons reached the most terminal region even after 5 months. At 5 months, gene expression associated with regeneration and pain sensitization, including Bdnf, cfos, and Gal, was decreased within dorsal root ganglia obtained from the acellular nerve allograft group compared to control or traction neurectomy group dorsal root ganglia. CONCLUSIONS Long acellular nerve allografts to cap a severed nerve arrested axon regeneration within the acellular nerve allograft. This growth arrest corresponded with changes in regenerative and pain-related genes upstream. Acellular nerve allografts may be useful for surgical intervention of neuroma.
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Cawthon CR, de La Serre CB. The critical role of CCK in the regulation of food intake and diet-induced obesity. Peptides 2021; 138:170492. [PMID: 33422646 DOI: 10.1016/j.peptides.2020.170492] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 12/16/2020] [Accepted: 12/23/2020] [Indexed: 12/17/2022]
Abstract
In 1973, Gibbs, Young, and Smith showed that exogenous cholecystokinin (CCK) administration reduces food intake in rats. This initial report has led to thousands of studies investigating the physiological role of CCK in regulating feeding behavior. CCK is released from enteroendocrine I cells present along the gastrointestinal (GI) tract. CCK binding to its receptor CCK1R leads to vagal afferent activation providing post-ingestive feedback to the hindbrain. Vagal afferent neurons' (VAN) sensitivity to CCK is modulated by energy status while CCK signaling regulates gene expression of other feeding related signals and receptors expressed by VAN. In addition to its satiation effects, CCK acts all along the GI tract to optimize digestion and nutrient absorption. Diet-induced obesity (DIO) is characterized by reduced sensitivity to CCK and every part of the CCK system is negatively affected by chronic intake of energy-dense foods. EEC have recently been shown to adapt to diet, CCK1R is affected by dietary fats consumption, and the VAN phenotypic flexibility is lost in DIO. Altered endocannabinoid tone, changes in gut microbiota composition, and chronic inflammation are currently being explored as potential mechanisms for diet driven loss in CCK signaling. This review discusses our current understanding of how CCK controls food intake in conditions of leanness and how control is lost in chronic energy excess and obesity, potentially perpetuating excessive intake.
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Affiliation(s)
- Carolina R Cawthon
- Department of Foods and Nutrition, University of Georgia, Athens, GA, USA
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Schalla MA, Taché Y, Stengel A. Neuroendocrine Peptides of the Gut and Their Role in the Regulation of Food Intake. Compr Physiol 2021; 11:1679-1730. [PMID: 33792904 DOI: 10.1002/cphy.c200007] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The regulation of food intake encompasses complex interplays between the gut and the brain. Among them, the gastrointestinal tract releases different peptides that communicate the metabolic state to specific nuclei in the hindbrain and the hypothalamus. The present overview gives emphasis on seven peptides that are produced by and secreted from specialized enteroendocrine cells along the gastrointestinal tract in relation with the nutritional status. These established modulators of feeding are ghrelin and nesfatin-1 secreted from gastric X/A-like cells, cholecystokinin (CCK) secreted from duodenal I-cells, glucagon-like peptide 1 (GLP-1), oxyntomodulin, and peptide YY (PYY) secreted from intestinal L-cells and uroguanylin (UGN) released from enterochromaffin (EC) cells. © 2021 American Physiological Society. Compr Physiol 11:1679-1730, 2021.
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Affiliation(s)
- Martha A Schalla
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Yvette Taché
- Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, CURE: Digestive Diseases Research Center, David Geffen School of Medicine, UCLA, Los Angeles, California, USA.,VA Greater Los Angeles Healthcare System, Los Angeles, California, USA
| | - Andreas Stengel
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany.,Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, Tübingen, Germany
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10
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Raza GS, Herzig K. The vagal nerves-Important connectors of the gut and brain for energy balance. Acta Physiol (Oxf) 2021; 231:e13605. [PMID: 33336510 DOI: 10.1111/apha.13605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 12/09/2020] [Accepted: 12/09/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Ghulam Shere Raza
- Institute of Biomedicine Medical Research Center Oulu Oulu UniversityOulu University Hospital Finland
| | - Karl‐Heinz Herzig
- Institute of Biomedicine Medical Research Center Oulu Oulu UniversityOulu University Hospital Finland
- Pediatric Institute Poznan University of Medical Sciences Poznan Poland
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Blanke EN, Holmes GM, Besecker EM. Altered physiology of gastrointestinal vagal afferents following neurotrauma. Neural Regen Res 2021; 16:254-263. [PMID: 32859772 PMCID: PMC7896240 DOI: 10.4103/1673-5374.290883] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The adaptability of the central nervous system has been revealed in several model systems. Of particular interest to central nervous system-injured individuals is the ability for neural components to be modified for regain of function. In both types of neurotrauma, traumatic brain injury and spinal cord injury, the primary parasympathetic control to the gastrointestinal tract, the vagus nerve, remains anatomically intact. However, individuals with traumatic brain injury or spinal cord injury are highly susceptible to gastrointestinal dysfunctions. Such gastrointestinal dysfunctions attribute to higher morbidity and mortality following traumatic brain injury and spinal cord injury. While the vagal efferent output remains capable of eliciting motor responses following injury, evidence suggests impairment of the vagal afferents. Since sensory input drives motor output, this review will discuss the normal and altered anatomy and physiology of the gastrointestinal vagal afferents to better understand the contributions of vagal afferent plasticity following neurotrauma.
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Affiliation(s)
- Emily N Blanke
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA, USA
| | - Gregory M Holmes
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA, USA
| | - Emily M Besecker
- Department of Health Sciences, Gettysburg College, Gettysburg, PA, USA
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Li Y, Cui ZJ. Photodynamic Activation of Cholecystokinin 1 Receptor with Different Genetically Encoded Protein Photosensitizers and from Varied Subcellular Sites. Biomolecules 2020; 10:biom10101423. [PMID: 33050050 PMCID: PMC7601527 DOI: 10.3390/biom10101423] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/01/2020] [Accepted: 10/06/2020] [Indexed: 02/07/2023] Open
Abstract
Cholecystokinin 1 receptor (CCK1R) is activated by singlet oxygen (1O2) generated in photodynamic action with sulphonated aluminum phthalocyanine (SALPC) or genetically encoded protein photosensitizer (GEPP) KillerRed or mini singlet oxygen generator (miniSOG). A large number of GEPP with varied 1O2 quantum yields have appeared recently; therefore, in the present work, the efficacy of different GEPP to photodynamically activate CCK1R was examined, as monitored by Fura-2 calcium imaging. KillerRed, miniSOG, miniSOG2, singlet oxygen protein photosensitizer (SOPP), flavin-binding fluorescent protein from Methylobacterium radiotolerans with point mutation C71G (Mr4511C71G), and flavin-binding fluorescent protein from Dinoroseobacter shibae (DsFbFP) were expressed at the plasma membrane (PM) in AR4-2J cells, which express endogenous CCK1R. Light irradiation (KillerRed: white light 85.3 mW‧cm-2, 4' and all others: LED 450 nm, 85 mW·cm-2, 1.5') of GEPPPM-expressing AR4-2J was found to all trigger persistent calcium oscillations, a hallmark of permanent photodynamic CCK1R activation; DsFbFP was the least effective, due to poor expression. miniSOG was targeted to PM, mitochondria (MT) or lysosomes (LS) in AR4-2J in parallel experiments; LED light irradiation was found to all induce persistent calcium oscillations. In miniSOGPM-AR4-2J cells, light emitting diode (LED) light irradiation-induced calcium oscillations were readily inhibited by CCK1R antagonist devazepide 2 nM; miniSOGMT-AR4-2J cells were less susceptible, but miniSOGLS-AR4-2J cells were not inhibited. In conclusion, different GEPPPM could all photodynamically activate CCK1R. Intracellular GEPP photodynamic action may prove particularly suited to study intracellular GPCR.
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Mayer F, Gunawan AL, Tso P, Aponte GW. Glucagon-like peptide 1 and glucose-dependent insulinotropic polypeptide stimulate release of substance P from TRPV1- and TRPA1-expressing sensory nerves. Am J Physiol Gastrointest Liver Physiol 2020; 319:G23-G35. [PMID: 32421358 PMCID: PMC7468754 DOI: 10.1152/ajpgi.00189.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are released from enteroendocrine cells (EECs) in response to nutrient ingestion and lower blood glucose levels by stimulation of insulin secretion and thus are defined as incretins. GLP-1 receptor (GLP-1R) expression has been identified on enteric neurons that include intrinsic afferent neurons, extrinsic spinal, and vagal sensory afferents but has not been shown to have an incretin effect through these nerves. GLP-1 and GIP enter the mesenteric lymphatic fluid (MLF) after a meal via the interstitial fluid (IF) from local tissue secretion and/or blood capillaries. We tested if MLF could induce diet-dependent intransient increases in intracellular calcium ([Ca2+]i) in cultured sensory neurons. Postprandial rat MLF, collected from the superior mesenteric lymphatic duct, induced a significant twofold higher intransient increase in [Ca2+]i in primary-cultured sensory neurons than MLF from fasted rats. Inhibition of transient receptor potential vanilloid 1 (TRPV1) and TRPV1 and ankyrin 1 cation channels (TRPA1) with ruthenium red eliminated the difference. Substance P (SP) (a peptide that stimulates insulin secretion) sensor cells cocultured with sensory neurons showed both the GLP-1R agonist exendin-4 (Ex-4) and GIP induced transient increases in [Ca2+]i directly coupled to SP secretion in the sensory nerves. Ex-4-induced release of SP required expression of either TRPA1 or TRPV1. These data identify unrecognized actions of GLP-1 and GIP as incretins by acting as neurolymphocrines and suggest a mechanism for sensory nerves to respond to the postprandial state through MLF.NEW & NOTEWORTHY Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are secreted upon eating to lower blood sugar. GLP-1 and GIP were found to induce the secretion of substance P (SP) from cultured sensory nerves. SP enhances insulin secretion. Mesenteric lymphatic fluid (MLF) also stimulates sensory neurons in a diet-dependent manner. These studies identify new actions of GLP-1 and GIP as incretins and suggest a mechanism for sensory nerves to respond to diet through MLF.
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Affiliation(s)
- Fahima Mayer
- 1Department of Nutritional Sciences and Toxicology, Graduate Program in Metabolic Biology, University of California, Berkeley, California
| | - Amanda L. Gunawan
- 1Department of Nutritional Sciences and Toxicology, Graduate Program in Metabolic Biology, University of California, Berkeley, California
| | - Patrick Tso
- 2Department of Pathobiology and Molecular Medicine, University of Cincinnati, Reading, Ohio
| | - Gregory W. Aponte
- 1Department of Nutritional Sciences and Toxicology, Graduate Program in Metabolic Biology, University of California, Berkeley, California
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Li Y, Cui ZJ. NanoLuc Bioluminescence-Driven Photodynamic Activation of Cholecystokinin 1 Receptor with Genetically-Encoded Protein Photosensitizer MiniSOG. Int J Mol Sci 2020; 21:ijms21113763. [PMID: 32466589 PMCID: PMC7313028 DOI: 10.3390/ijms21113763] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/21/2020] [Accepted: 05/25/2020] [Indexed: 02/07/2023] Open
Abstract
In contrast to reversible activation by agonist, cholecystokinin 1 receptor (CCK1R) is permanently activated by singlet oxygen generated in photodynamic action, with sulphonated aluminium phthalocyanine or genetically encoded mini singlet oxygen generator (miniSOG) as photosensitizer. In these works, a halogen light source was used to power photodynamic action. For possible in vivo application of photodynamic CCK1R physiology, bearing a cumbersome light-delivery device connected to an external light source by experimental animals might interfere with their behavior. Therefore, in the present work, the possibility of bioluminescence-driven miniSOG photodynamic CCK1R activation was examined, as monitored by Fura-2 calcium imaging. In parallel experiments, it was found that, after plasma membrane (PM)-localized expression of miniSOGPM in AR4-2J cells, light irradiation with blue light-emitting diode (LED) (450 nm, 85 mW·cm-2, 1.5 min) induced persistent calcium oscillations that were blocked by CCK1R antagonist devazepide 2 nM. NanoLuc was expressed bicistronically with miniSOGPM via an internal ribosome entry site (IRES) sequence (pminiSOGPM-IRES-NanoLuc). The resultant miniSOGPM-IRES-NanoLuc-AR4-2J cells were found to generate strong bioluminescence upon addition of NanoLuc substrate coelenterazine. Strikingly, coelenterazine 5 microM was found to trigger long-lasting calcium oscillations (a hallmark for permanent CCK1R activation) in perifused miniSOGPM-IRES-NanoLuc-AR4-2J cells. These data indicate that NanoLuc bioluminescence can drive miniSOGPM photodynamic CCK1R activation, laying the foundation for its future in vivo applications.
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Cholecystokinin-1 receptor agonist induced pathological findings in the exocrine pancreas of non-human primates. Toxicol Appl Pharmacol 2020; 399:115035. [PMID: 32422327 DOI: 10.1016/j.taap.2020.115035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 04/24/2020] [Accepted: 05/05/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Cholecystokinin (CCK) may potentially be used to treat obesity. However, it is well-known to induce acute pancreatitis and pancreas neoplasia in rodents, but not in primates. Here we report the nonclinical safety profile of a long-acting CCK-1 receptor (CCK-1R) agonist, NN9056, in rats and monkeys to support a First-in-Man clinical trial with NN9056. METHODS Thirteen-week toxicological studies were conducted in rats and non-human primates followed by histopathological evaluation of affected tissues. NN9056 was characterised in vitro, and CCK-1R expression was assessed by in situ hybridization in cynomolgus monkey and human pancreas tissues. RESULTS Affinity and potency of NN9056 was comparable to native sulphated CCK-8 (CCK-8) across species on the CCK-1R while it had no effect on the CCK-2 receptor (CCK-2R). In situ hybridization demonstrated abundant expression of CCK-1Rs in the exocrine pancreas of the rat. In contrast, it was only discreetly expressed on pancreatic acinar cells in the periphery of scattered lobules in monkeys. A similar expression pattern was observed in human pancreas. 13-weeks daily dosing with NN9056 produced the expected pancreatic pathological findings in rats. In monkeys, NN9056 increased pancreas weight and induced histopathological changes despite the low expression level of CCK-1Rs. CONCLUSION Surprisingly, chronic CCK-1R activation constitutes a risk for pancreatitis and trophic actions on the exocrine pancreas in monkeys. Since similar CCK-1R expression patterns were found in pancreas of monkeys and humans this risk is likely translatable to humans and clinical development of NN9056 was therefore halted.
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Dafalla AI, Mhalhal TR, Hiscocks K, Heath J, Sayegh AI. The Vagus Nerve and the Celiaco-mesenteric Ganglia Participate in the Feeding Responses Evoked by Non-sulfated Cholecystokinin-8 in Male Sprague Dawley Rats. Endocr Res 2020; 45:73-83. [PMID: 31573821 DOI: 10.1080/07435800.2019.1670673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We have shown that non-sulfated cholecystokinin-8 (NS CCK-8) reduces food intake in adult male Sprague Dawley rats by activating cholecystokinin-B receptor (CCK-BR). Here, we tested the hypothesis that the vagus nerve and the celiaco-mesenteric ganglia may play a role in this reduction. The hypothesis stems from the following facts. The vagus and the celiaco-mesenteric ganglia contain NS CCK-8, they express and have binding sites for CCK-BR, NS CCK-8 activates CCK-BR on afferent vagal and sympathetic fibers and the two structures link the gastrointestinal tract to central feeding nuclei in the brain, which also contain the peptide and CCK-BR. To test this hypothesis, three groups of free-feeding rats, vagotomy (VGX), celiaco-mesenteric ganglionectomy (CMGX) and sham-operated, received NS CCK-8 (0, 0.5 and 1 nmol/kg) intraperitoneally prior to the onset of the dark cycle and various feeding behaviors were recorded. We found that in sham-operated rats both doses of NS CCK-8 reduced meal size (MS), prolonged the intermeal interval (IMI, time between first and second meal), increased satiety ratio (SR = IMI/MS), reduced 24-h food intake and reduced the number of meals relative to saline control. In the VGX and the CMGX groups, all of the previous responses were attenuated. Consistent with our hypothesis, the findings of the current work suggest a role for the vagus nerve and the celiaco-mesenteric ganglia in the feeding responses evoked by NS CCK-8.
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Affiliation(s)
- Amged I Dafalla
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - Thaer R Mhalhal
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
- Department of Anatomy and Histology, College of Veterinary Medicine, Basra University, Basra, Iraq
| | - Kenneth Hiscocks
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - John Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
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Besecker EM, Blanke EN, Deiter GM, Holmes GM. Gastric vagal afferent neuropathy following experimental spinal cord injury. Exp Neurol 2019; 323:113092. [PMID: 31697943 DOI: 10.1016/j.expneurol.2019.113092] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/11/2019] [Accepted: 10/23/2019] [Indexed: 01/01/2023]
Abstract
Dramatic impairment of gastrointestinal (GI) function accompanies high-thoracic spinal cord injury (T3-SCI). The vagus nerve contains mechano- and chemosensory fibers as well as the motor fibers necessary for the central nervous system (CNS) control of GI reflexes. Cell bodies for the vagal afferent fibers are located within the nodose gangla (NG) and the majority of vagal afferent axons are unmyelinated C fibers that are sensitive to capsaicin through activation of transient receptor potential vanilloid-1 (TRPV1) channels. Vagal afferent fibers also express receptors for GI hormones, including cholecystokinin (CCK). Previously, T3-SCI provokes a transient GI inflammatory response as well as a reduction of both gastric emptying and centrally-mediated vagal responses to GI peptides, including CCK. TRPV1 channels and CCK-A receptors (CCKar) expressed in vagal afferents are upregulated in models of visceral inflammation. The present study investigated whether T3-SCI attenuates peripheral vagal afferent sensitivity through plasticity of TRPV1 and CCK receptors. Vagal afferent response to graded mechanical stimulation of the stomach was significantly attenuated by T3-SCI at 3-day and 3-week recovery. Immunocytochemical labeling for CCKar and TRPV1 demonstrated expression on dissociated gastric-projecting NG neurons. Quantitative assessment of mRNA expression by qRT-PCR revealed significant elevation of CCKar and TRPV1 in the whole NG following T3-SCI in 3-day recovery, but levels returned to normal after 3-weeks. Three days after injury, systemic administration of CCK-8 s showed a significantly diminished gastric vagal afferent response in T3-SCI rats compared to control rats while systemic capsaicin infusion revealed a significant elevation of vagal response in T3-SCI vs control rats. These findings demonstrate that T3-SCI provokes peripheral remodeling and prolonged alterations in the response of vagal afferent fibers to the physiological signals associated with digestion.
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Affiliation(s)
- Emily M Besecker
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States of America; Department of Health Sciences, Gettysburg College, Gettysburg, PA 17325, United States of America
| | - Emily N Blanke
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States of America
| | - Gina M Deiter
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States of America
| | - Gregory M Holmes
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United States of America.
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Holmes GM, Blanke EN. Gastrointestinal dysfunction after spinal cord injury. Exp Neurol 2019; 320:113009. [PMID: 31299180 PMCID: PMC6716787 DOI: 10.1016/j.expneurol.2019.113009] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 06/13/2019] [Accepted: 07/07/2019] [Indexed: 12/12/2022]
Abstract
The gastrointestinal tract of vertebrates is a heterogeneous organ system innervated to varying degrees by a local enteric neural network as well as extrinsic parasympathetic and sympathetic neural circuits located along the brainstem and spinal axis. This diverse organ system serves to regulate the secretory and propulsive reflexes integral to the digestion and absorption of nutrients. The quasi-segmental distribution of the neural circuits innervating the gastrointestinal (GI) tract produces varying degrees of dysfunction depending upon the level of spinal cord injury (SCI). At all levels of SCI, GI dysfunction frequently presents life-long challenges to individuals coping with injury. Growing attention to the profound changes that occur across the entire physiology of individuals with SCI reveals profound knowledge gaps in our understanding of the temporal dimensions and magnitude of organ-specific co-morbidities following SCI. It is essential to understand and identify these broad pathophysiological changes in order to develop appropriate evidence-based strategies for management by clinicians, caregivers and individuals living with SCI. This review summarizes the neurophysiology of the GI tract in the uninjured state and the pathophysiology associated with the systemic effects of SCI.
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Affiliation(s)
- Gregory M Holmes
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United states of America.
| | - Emily N Blanke
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, United states of America
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Bao L, Zhao J, Liao D, Wang G, Gregersen H. Refeeding reverses fasting-induced remodeling of afferent nerve activity in rat small intestine. Biomech Model Mechanobiol 2019; 18:1915-1926. [DOI: 10.1007/s10237-019-01185-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/05/2019] [Indexed: 02/08/2023]
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20
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Dafalla AI, Mhalhal TR, Washington MC, Spann S, Reguero AM, Morgan AL, Cruz Matos GA, Carson G, Barton KJ, Burke NA, Heath J, Sayegh AI. Non-sulfated cholecystokinin-8 reduces meal size and prolongs the intermeal interval in male Sprague Dawley rats. Neuropeptides 2019; 73:57-65. [PMID: 30470455 PMCID: PMC6613573 DOI: 10.1016/j.npep.2018.11.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/09/2018] [Accepted: 11/12/2018] [Indexed: 12/15/2022]
Abstract
The current study measured seven feeding responses by non-sulfated cholecystokinin-8 (NS CCK-8) in freely fed adult male Sprague Dawley rats. The peptide (0, 0.5, 1, 3, 5 and 10 nmol/kg) was given intraperitoneally (ip) prior to the onset of the dark cycle, and first meal size (MS), second meal size, intermeal interval (IMI) length, satiety ratio (SR = IMI/MS), latency to first meal, duration of first meal, number of meals and 24-hour food intake were measured. We found that NS CCK-8 (0.5 and 1.0 nmol/kg) reduced MS, prolonged IMI length and increased SR during the dark cycle. Furthermore, the specific CCK-B receptor antagonist L365, 260 (1 mg/kg, ip) attenuated these responses. These results support a possible role for NS CCK-8 in regulating food intake.
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Affiliation(s)
- Amged I Dafalla
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Thaer R Mhalhal
- Department of Anatomy and Histology, College of Veterinary Medicine, Basrah University, Basrah, Iraq
| | - Martha C Washington
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Sharonika Spann
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Adalis Montero Reguero
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Alexandra L Morgan
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Geishly A Cruz Matos
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Gabrielle Carson
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Kenya J Barton
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Nicole A Burke
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - John Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, United States.
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Abstract
The regulation of energy and glucose balance contributes to whole-body metabolic homeostasis, and such metabolic regulation is disrupted in obesity and diabetes. Metabolic homeostasis is orchestrated partly in response to nutrient and vagal-dependent gut-initiated functions. Specifically, the sensory and motor fibres of the vagus nerve transmit intestinal signals to the central nervous system and exert biological and physiological responses. In the past decade, the understanding of the regulation of vagal afferent signals and of the associated metabolic effect on whole-body energy and glucose balance has progressed. This Review highlights the contributions made to the understanding of the vagal afferent system and examines the integrative role of the vagal afferent in gastrointestinal regulation of appetite and glucose homeostasis. Investigating the integrative and metabolic role of vagal afferent signalling represents a potential strategy to discover novel therapeutic targets to restore energy and glucose balance in diabetes and obesity.
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22
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Jiang WY, Li Y, Li ZY, Cui ZJ. Permanent Photodynamic Cholecystokinin 1 Receptor Activation: Dimer-to-Monomer Conversion. Cell Mol Neurobiol 2018; 38:1283-1292. [PMID: 29869099 DOI: 10.1007/s10571-018-0596-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 05/30/2018] [Indexed: 02/07/2023]
Abstract
The G protein-coupled cholecystokinin 1 receptor (CCK1R) is activated permanently by type II photodynamic action (i.e., by singlet oxygen) in the freshly isolated rat pancreatic acini, in contrast to reversible activation by CCK. But how CCK1R is photodynamically activated is not known. Therefore, in the present work, we subjected membrane proteins extracted from isolated rat pancreatic acini to photodynamic action with photosensitiser sulphonated aluminium phthalocyanine (SALPC), and used reducing gel electrophoresis and Western blot to detect possible changes in CCK1R oligomerization status. Photodynamic action (SALPC 1 µM, light 36.7 mW cm- 2 × 10 min) was found to convert dimeric CCK1R nearly quantitatively to monomers. Such conversion was dependent on both irradiance (8.51-36.7 mW cm- 2) and irradiation time (1-20 min). Minimum effective irradiance was found to be 11.1 mW cm- 2 (× 10 min, with SALPC 1 µM), and brief photodynamic action (SALPC 1 µM, 36.7 mW cm- 2 × 1 min) was effective. Whilst CCK stimulation of purified membrane proteins alone had no effect on CCK1R dimer/monomer balance, sub-threshold photodynamic action (SALPC 100 nM, 36.7 mW cm- 2 × 10 min) plus CCK revealed a bell-shaped CCK dose response curve for CCK1R monomerization, which was remarkably similar to the dose response curve for CCK-stimulated amylase secretion in isolated rat pancreatic acini. These two lines of evidence together suggest that during photodynamic CCK1R activation, CCK1R is permanently monomerized, thus providing a unique approach for permanent G protein-coupled receptor (GPCR) activation which has not been achieved before.
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Affiliation(s)
- Wen Yi Jiang
- Institute of Cell Biology, Beijing Normal University, Beijing, 100875, China
| | - Yuan Li
- Institute of Cell Biology, Beijing Normal University, Beijing, 100875, China
| | - Zhi Ying Li
- Institute of Cell Biology, Beijing Normal University, Beijing, 100875, China
| | - Zong Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing, 100875, China.
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Egerod KL, Petersen N, Timshel PN, Rekling JC, Wang Y, Liu Q, Schwartz TW, Gautron L. Profiling of G protein-coupled receptors in vagal afferents reveals novel gut-to-brain sensing mechanisms. Mol Metab 2018; 12:62-75. [PMID: 29673577 PMCID: PMC6001940 DOI: 10.1016/j.molmet.2018.03.016] [Citation(s) in RCA: 114] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 03/24/2018] [Accepted: 03/29/2018] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVES G protein-coupled receptors (GPCRs) act as transmembrane molecular sensors of neurotransmitters, hormones, nutrients, and metabolites. Because unmyelinated vagal afferents richly innervate the gastrointestinal mucosa, gut-derived molecules may directly modulate the activity of vagal afferents through GPCRs. However, the types of GPCRs expressed in vagal afferents are largely unknown. Here, we determined the expression profile of all GPCRs expressed in vagal afferents of the mouse, with a special emphasis on those innervating the gastrointestinal tract. METHODS Using a combination of high-throughput quantitative PCR, RNA sequencing, and in situ hybridization, we systematically quantified GPCRs expressed in vagal unmyelinated Nav1.8-expressing afferents. RESULTS GPCRs for gut hormones that were the most enriched in Nav1.8-expressing vagal unmyelinated afferents included NTSR1, NPY2R, CCK1R, and to a lesser extent, GLP1R, but not GHSR and GIPR. Interestingly, both GLP1R and NPY2R were coexpressed with CCK1R. In contrast, NTSR1 was coexpressed with GPR65, a marker preferentially enriched in intestinal mucosal afferents. Only few microbiome-derived metabolite sensors such as GPR35 and, to a lesser extent, GPR119 and CaSR were identified in the Nav1.8-expressing vagal afferents. GPCRs involved in lipid sensing and inflammation (e.g. CB1R, CYSLTR2, PTGER4), and neurotransmitters signaling (CHRM4, DRD2, CRHR2) were also highly enriched in Nav1.8-expressing neurons. Finally, we identified 21 orphan GPCRs with unknown functions in vagal afferents. CONCLUSION Overall, this study provides a comprehensive description of GPCR-dependent sensing mechanisms in vagal afferents, including novel coexpression patterns, and conceivably coaction of key receptors for gut-derived molecules involved in gut-brain communication.
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Affiliation(s)
- Kristoffer L Egerod
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, and Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Nørre Allé 14, 2200, Copenhagen, Denmark.
| | - Natalia Petersen
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, and Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Nørre Allé 14, 2200, Copenhagen, Denmark
| | - Pascal N Timshel
- Nordisk Foundation Center for Basic Metabolic Research, Section of Metabolic Genomics, Faculty of Health and Medical Sciences, University of Copenhagen, Nørre Allé 14, 2200, Copenhagen, Denmark
| | - Jens C Rekling
- Department of Neuroscience, University of Copenhagen, Nørre Allé 14, 2200, Copenhagen, Denmark
| | - Yibing Wang
- Department of Biochemistry, UT Southwestern Medical Center at Dallas, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Qinghua Liu
- Department of Biochemistry, UT Southwestern Medical Center at Dallas, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Thue W Schwartz
- Laboratory for Molecular Pharmacology, Department of Biomedical Sciences, and Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Nørre Allé 14, 2200, Copenhagen, Denmark
| | - Laurent Gautron
- Division of Hypothalamic Research and Department of Internal Medicine, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.
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Jiang HN, Li Y, Jiang WY, Cui ZJ. Cholecystokinin 1 Receptor - A Unique G Protein- Coupled Receptor Activated by Singlet Oxygen ( GPCR-ABSO). Front Physiol 2018; 9:497. [PMID: 29867546 PMCID: PMC5953346 DOI: 10.3389/fphys.2018.00497] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 04/18/2018] [Indexed: 02/05/2023] Open
Abstract
Plasma membrane-delimited generation of singlet oxygen by photodynamic action with photosensitizer sulfonated aluminum phthalocyanine (SALPC) activates cholecystokinin 1 receptor (CCK1R) in pancreatic acini. Whether CCK1R retains such photooxidative singlet oxygen activation properties in other environments is not known. Genetically encoded protein photosensitizers KillerRed or mini singlet oxygen generator (miniSOG) were expressed in pancreatic acinar tumor cell line AR4-2J, CCK1R, KillerRed or miniSOG were expressed in HEK293 or CHO-K1 cells. Cold light irradiation (87 mW⋅cm-2) was applied to photosensitizer-expressing cells to examine photodynamic activation of CCK1R by Fura-2 fluorescent calcium imaging. When CCK1R was transduced into HEK293 cells which lack endogenous CCK1R, photodynamic action with SALPC was found to activate CCK1R in CCK1R-HEK293 cells. When KillerRed or miniSOG were transduced into AR4-2J which expresses endogenous CCK1R, KillerRed or miniSOG photodynamic action at the plasma membrane also activated CCK1R. When fused KillerRed-CCK1R was transduced into CHO-K1 cells, light irradiation activated the fused CCK1R leading to calcium oscillations. Therefore KillerRed either expressed independently, or fused with CCK1R can both activate CCK1R photodynamically. It is concluded that photodynamic singlet oxygen activation is an intrinsic property of CCK1R, independent of photosensitizer used, or CCK1R-expressing cell types. Photodynamic singlet oxygen CCK1R activation after transduction of genetically encoded photosensitizer in situ may provide a convenient way to verify intrinsic physiological functions of CCK1R in multiple CCK1R-expressing cells and tissues, or to actuate CCK1R function in CCK1R-expressing and non-expressing cell types after transduction with fused KillerRed-CCK1R.
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Diepenbroek C, Quinn D, Stephens R, Zollinger B, Anderson S, Pan A, de Lartigue G. Validation and characterization of a novel method for selective vagal deafferentation of the gut. Am J Physiol Gastrointest Liver Physiol 2017; 313:G342-G352. [PMID: 28705805 PMCID: PMC5668568 DOI: 10.1152/ajpgi.00095.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/01/2017] [Accepted: 06/23/2017] [Indexed: 01/31/2023]
Abstract
There is a lack of tools that selectively target vagal afferent neurons (VAN) innervating the gut. We use saporin (SAP), a potent neurotoxin, conjugated to the gastronintestinal (GI) hormone cholecystokinin (CCK-SAP) injected into the nodose ganglia (NG) of male Wistar rats to specifically ablate GI-VAN. We report that CCK-SAP ablates a subpopulation of VAN in culture. In vivo, CCK-SAP injection into the NG reduces VAN innervating the mucosal and muscular layers of the stomach and small intestine but not the colon, while leaving vagal efferent neurons intact. CCK-SAP abolishes feeding-induced c-Fos in the NTS, as well as satiation by CCK or glucagon like peptide-1 (GLP-1). CCK-SAP in the NG of mice also abolishes CCK-induced satiation. Therefore, we provide multiple lines of evidence that injection of CCK-SAP in NG is a novel selective vagal deafferentation technique of the upper GI tract that works in multiple vertebrate models. This method provides improved tissue specificity and superior separation of afferent and efferent signaling compared with vagotomy, capsaicin, and subdiaphragmatic deafferentation.NEW & NOTEWORTHY We develop a new method that allows targeted lesioning of vagal afferent neurons that innervate the upper GI tract while sparing vagal efferent neurons. This reliable approach provides superior tissue specificity and selectivity for vagal afferent over efferent targeting than traditional approaches. It can be used to address questions about the role of gut to brain signaling in physiological and pathophysiological conditions.
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Affiliation(s)
- Charlene Diepenbroek
- The John B. Pierce Laboratory, New Haven, Connecticut
- Department of Cellular and Molecular Physiology, Yale Medical School, New Haven, Connecticut; and
| | | | - Ricky Stephens
- Department of Anatomy, Physiology, and Cell Biology, University of California Davis, Davis, California
| | | | - Seth Anderson
- The John B. Pierce Laboratory, New Haven, Connecticut
| | - Annabelle Pan
- The John B. Pierce Laboratory, New Haven, Connecticut
| | - Guillaume de Lartigue
- The John B. Pierce Laboratory, New Haven, Connecticut;
- Department of Cellular and Molecular Physiology, Yale Medical School, New Haven, Connecticut; and
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Weng J, Lou D, Benoit SC, Coschigano N, Woods SC, Tso P, Lo CC. Energy homeostasis in apolipoprotein AIV and cholecystokinin-deficient mice. Am J Physiol Regul Integr Comp Physiol 2017; 313:R535-R548. [PMID: 28768657 DOI: 10.1152/ajpregu.00034.2017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 07/25/2017] [Accepted: 07/26/2017] [Indexed: 11/22/2022]
Abstract
Apolipoprotein AIV (ApoAIV) and cholecystokinin (CCK) are well-known satiating signals that are stimulated by fat consumption. Peripheral ApoAIV and CCK interact to prolong satiating signals. In the present study, we hypothesized that ApoAIV and CCK control energy homeostasis in response to high-fat diet feeding. To test this hypothesis, energy homeostasis in ApoAIV and CCK double knockout (ApoAIV/CCK-KO), ApoAIV knockout (ApoAIV-KO), and CCK knockout (CCK-KO) mice were monitored. When animals were maintained on a low-fat diet, ApoAIV/CCK-KO, ApoAIV-KO, and CCK-KO mice had comparable energy intake and expenditure, body weight, fat mass, fat absorption, and plasma parameters relative to the controls. In contrast, these KO mice exhibited impaired lipid transport to epididymal fat pads in response to intraduodenal infusion of dietary lipids. Furthermore, ApoAIV-KO mice had upregulated levels of CCK receptor 2 (CCK2R) in the small intestine while ApoAIV/CCK-KO mice had upregulated levels of CCK2R in the brown adipose tissue. After 20 wk of a high-fat diet, ApoAIV-KO and CCK-KO mice had comparable body weight and fat mass, as well as lower energy expenditure at some time points. However, ApoAIV/CCK-KO mice exhibited reduced body weight and adiposity relative to wild-type mice, despite having normal food intake. Furthermore, ApoAIV/CCK-KO mice displayed normal fat absorption and locomotor activity, as well as enhanced energy expenditure. These observations suggest that mice lacking ApoAIV and CCK have reduced body weight and adiposity, possibly due to impaired lipid transport and elevated energy expenditure.
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Affiliation(s)
- Jonathan Weng
- Department of Biomedical Sciences, Molecular and Cellular Biology Program, and Diabetes Institute, Ohio University, Athens, Ohio.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, NewYork
| | - Danwen Lou
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio; and
| | - Stephen C Benoit
- Department of Psychiatry, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio
| | - Natalie Coschigano
- Department of Biomedical Sciences, Molecular and Cellular Biology Program, and Diabetes Institute, Ohio University, Athens, Ohio
| | - Stephen C Woods
- Department of Psychiatry, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio
| | - Patrick Tso
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio; and
| | - Chunmin C Lo
- Department of Biomedical Sciences, Molecular and Cellular Biology Program, and Diabetes Institute, Ohio University, Athens, Ohio;
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27
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Ballaz S. The unappreciated roles of the cholecystokinin receptor CCK(1) in brain functioning. Rev Neurosci 2017; 28:573-585. [DOI: 10.1515/revneuro-2016-0088] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/05/2017] [Indexed: 12/13/2022]
Abstract
AbstractThe CCK(1) receptor is a G-protein-coupled receptor activated by the sulfated forms of cholecystokinin (CCK), a gastrin-like peptide released in the gastrointestinal tract and mammal brain. A substantial body of research supports the hypothesis that CCK(1)r stimulates gallbladder contraction and pancreatic secretion in the gut, as well as satiety in brain. However, this receptor may also fulfill relevant roles in behavior, thanks to its widespread distribution in the brain. The strategic location of CCK(1)r in mesolimbic structures and specific hypothalamic and brainstem nuclei lead to complex interactions with neurotransmitters like dopamine, serotonin, and glutamate, as well as hypothalamic hormones and neuropeptides. The activity of CCK(1)r maintains adequate levels of dopamine and regulates the activity of serotonin neurons of raphe nuclei, which makes CCK(1)r an interesting therapeutic target for the development of adjuvant treatments for schizophrenia, drug addiction, and mood disorders. Unexplored functions of CCK(1)r, like the transmission of interoceptive sensitivity in addition to the regulation of hypothalamic hormones and neurotransmitters affecting emotional states, well-being, and attachment behaviors, may open exciting roads of research. The absence of specific ligands for the CCK(1) receptor has complicated the study of its distribution in brain so that research about its impact on behavior has been published sporadically over the last 30 years. The present review reunites all this body of evidence in a comprehensive way to summarize our knowledge about the actual role of CCK in the neurobiology of mental illness.
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Affiliation(s)
- Santiago Ballaz
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San Jose y Proyecto Yachay s/n, San Miguel de Urcuquí 100119, Ecuador
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Grabauskas G, Owyang C. Plasticity of vagal afferent signaling in the gut. MEDICINA-LITHUANIA 2017; 53:73-84. [PMID: 28454890 PMCID: PMC6318799 DOI: 10.1016/j.medici.2017.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 03/21/2017] [Indexed: 12/13/2022]
Abstract
Vagal sensory neurons mediate the vago-vagal reflex which, in turn, regulates a wide array of gastrointestinal functions including esophageal motility, gastric accommodation and pancreatic enzyme secretion. These neurons also transmit sensory information from the gut to the central nervous system, which then mediates the sensations of nausea, fullness and satiety. Recent research indicates that vagal afferent neurons process non-uniform properties and a significant degree of plasticity. These properties are important to ensure that vagally regulated gastrointestinal functions respond rapidly and appropriately to various intrinsic and extrinsic factors. Similar plastic changes in the vagus also occur in pathophysiological conditions, such as obesity and diabetes, resulting in abnormal gastrointestinal functions. A clear understanding of the mechanisms which mediate these events may provide novel therapeutic targets for the treatment of gastrointestinal disorders due to vago-vagal pathway malfunctions.
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Affiliation(s)
- Gintautas Grabauskas
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48019, USA.
| | - Chung Owyang
- Division of Gastroenterology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48019, USA
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29
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Ndjim M, Poinsignon C, Parnet P, Le Dréan G. Loss of Vagal Sensitivity to Cholecystokinin in Rats Born with Intrauterine Growth Retardation and Consequence on Food Intake. Front Endocrinol (Lausanne) 2017; 8:65. [PMID: 28443064 PMCID: PMC5385335 DOI: 10.3389/fendo.2017.00065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 03/23/2017] [Indexed: 01/05/2023] Open
Abstract
Perinatal malnutrition is associated with low birth weight and an increased risk of developing metabolic syndrome in adulthood. Modification of food intake (FI) regulation was observed in adult rats born with intrauterine growth retardation induced by maternal dietary protein restriction during gestation and maintained restricted until weaning. Gastrointestinal peptides and particularly cholecystokinin (CCK) play a major role in short-term regulation of FI by relaying digestive signals to the hindbrain via the vagal afferent nerve (VAN). We hypothesized that vagal sensitivity to CCK could be affected in rats suffering from undernutrition [low protein (LP)] during fetal and postnatal life, leading to an altered gut-brain communication and impacting satiation. Our aim was to study short-term FI along with signals of appetite and satiation in adult LP rats compared to control rats. The dose-response to CCK injection was investigated on FI as well as the associated signaling pathways activated in nodose ganglia. We showed that LP rats have a reduced first-meal satiety ratio after a fasting period associated to a higher postprandial plasmatic CCK release, a reduced sensitivity to CCK when injected at low concentration and a reduced presence of CCK-1 receptor in nodose ganglia. Accordingly, the lower basal and CCK-induced phosphorylation of calcium/calmodulin-dependent protein kinase in nodose ganglia of LP rats could reflect an under-expressed vanilloid family of transient receptor potential cation channels on VAN. Altogether, the present data demonstrated a reduced vagal sensitivity to CCK in LP rats at adulthood, which could contribute to deregulation of FI reported in this model.
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Affiliation(s)
- Marième Ndjim
- UMR 1280 PHAN, INRA, Université de Nantes, Institut des Maladies de l’Appareil Digestif (IMAD), Centre de Recherche en Nutrition Humaine Ouest (CRNH Ouest), Nantes, France
| | - Camille Poinsignon
- UMR 1280 PHAN, INRA, Université de Nantes, Institut des Maladies de l’Appareil Digestif (IMAD), Centre de Recherche en Nutrition Humaine Ouest (CRNH Ouest), Nantes, France
| | - Patricia Parnet
- UMR 1280 PHAN, INRA, Université de Nantes, Institut des Maladies de l’Appareil Digestif (IMAD), Centre de Recherche en Nutrition Humaine Ouest (CRNH Ouest), Nantes, France
| | - Gwenola Le Dréan
- UMR 1280 PHAN, INRA, Université de Nantes, Institut des Maladies de l’Appareil Digestif (IMAD), Centre de Recherche en Nutrition Humaine Ouest (CRNH Ouest), Nantes, France
- *Correspondence: Gwenola Le Dréan,
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Kaczyńska K, Szereda-Przestaszewska M. Contribution of CCK1 receptors to cardiovascular and respiratory effects of cholecystokinin in anesthetized rats. Neuropeptides 2015; 54:29-34. [PMID: 26342277 DOI: 10.1016/j.npep.2015.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 06/22/2015] [Accepted: 08/06/2015] [Indexed: 10/23/2022]
Abstract
The study investigated the share of vagal input at infra- and supra-nodosal level and the contribution of CCK1 and CCK2 receptors to the cardiorespiratory responses produced by an intravenous injection of sulfated cholecystokinin octapeptide (CCK-8) in anesthetized rats. This compound administered intravenously at a dose of 50μg/kg induced short-lived decline in tidal volume and respiratory rate resulting in depression of minute ventilation. Midcervical vagotomy had no effect on CCK-8-evoked ventilatory changes, whereas supranodosal denervation abolished slowing down of breathing. Cardiovascular response to CCK challenge was characterized by a transient decrease followed by an augmentation in the mean blood pressure (MAP) in the intact animals. Vagotomy performed at both levels abrogated the declining phase of MAP. Blood pressure changes were associated with decreased heart rate present in all neural states. All cardiovascular and respiratory effects were antagonized by pre-treatment with devazepide-CCK1 receptors' antagonist, whereas CI988-antagonist of CCK2 receptors was ineffective. In conclusion, our results indicate that CCK-8 modulates slowing down of respiratory rhythm via CCK1 receptors located in the nodose ganglia (NG) and depresses tidal volume via central CCK1 dependent mechanism. CCK-8-evoked decline in blood pressure may be due to activation of vagal afferents, whereas pressor responses seem to be mediated by an activation of CCK1 receptors in the central nervous system. Bradycardia was probably induced by the direct action of CCK-8 on the heart pacemaker cells.
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Affiliation(s)
- Katarzyna Kaczyńska
- Laboratory of Respiration Physiology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5, 02-106 Warsaw, Poland.
| | - Małgorzata Szereda-Przestaszewska
- Laboratory of Respiration Physiology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Pawińskiego 5, 02-106 Warsaw, Poland
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Wang EM, Li WT, Yan XJ, Chen X, Liu Q, Feng CC, Cao ZJ, Fang JY, Chen SL. Vagal afferent-dependent cholecystokinin modulation of visceral pain requires central amygdala NMDA-NR2B receptors in rats. Neurogastroenterol Motil 2015. [PMID: 26197883 DOI: 10.1111/nmo.12633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Cholecystokinin (CCK), a gut hormone that is released during feeding, exerts gastrointestinal effects in part through vagal pathway. It is reported to be a potential trigger for increased postprandial visceral sensitivity in healthy subjects and, especially in patients with irritable bowel syndrome. NR2B-containing N-methyl-d-aspartate (NMDA) receptors in the central amygdala (CeA) participate in pain modulation. Systemically administered CCK activates the CeA-innervating neurons. Here, we investigated whether CCK modulation of visceral sensitivity is mediated through CeA NMDA-NR2B receptors and whether this modulation involves vagal pathway. METHODS We first examined the visceromotor response (VMR) to colorectal distention (CRD) following i.p. injection of CCK octapeptide (CCK-8) in a rat model. Next, the NR2B antagonist ifenprodil and the NR2A antagonist NVP-AAM077 were microinjected into the CeA before systemic CCK injection. NR2B phosphorylation was detected by Western blot. To down-regulate NR2B gene expression, NR2B-specific small interfering RNA (siRNA) was delivered into CeA neurons by electroporation. In addition, the effects of functional deafferentation by perivagal application of capsaicin and pretreatment with the CCK1 receptor antagonist devazepide were investigated. KEY RESULTS CCK-8 increased VMR to CRD in a dose-dependent manner. This effect was blunted by intra-CeA administration of ifenprodil (but not NVP-AAM077) and was accompanied by phosphorylation of NR2B subunits in the CeA. CCK failed to increase VMR to CRD in NR2B siRNA-treated rats. Perivagal capsaicin application and pretreatment with devazepide prevented CCK-induced pronociception and CeA NR2B phosphorylation. CONCLUSIONS & INFERENCES The pronociception induced by systemic CCK, which is vagal afferent-dependent, requires activation of CeA NMDA-NR2B receptors.
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Affiliation(s)
- E M Wang
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - W T Li
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - X J Yan
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - X Chen
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - Q Liu
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - C C Feng
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - Z J Cao
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - J Y Fang
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - S L Chen
- Division of Gastroenterology and Hepatology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
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Reynders A, Mantilleri A, Malapert P, Rialle S, Nidelet S, Laffray S, Beurrier C, Bourinet E, Moqrich A. Transcriptional Profiling of Cutaneous MRGPRD Free Nerve Endings and C-LTMRs. Cell Rep 2015; 10:1007-1019. [PMID: 25683706 PMCID: PMC4542317 DOI: 10.1016/j.celrep.2015.01.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/13/2014] [Accepted: 01/08/2015] [Indexed: 01/06/2023] Open
Abstract
Cutaneous C-unmyelinated MRGPRD+ free nerve endings and C-LTMRs innervating hair follicles convey two opposite aspects of touch sensation: a sensation of pain and a sensation of pleasant touch. The molecular mechanisms underlying these diametrically opposite functions are unknown. Here, we used a mouse model that genetically marks C-LTMRs and MRGPRD+ neurons in combination with fluorescent cell surface labeling, flow cytometry, and RNA deep-sequencing technology (RNA-seq). Cluster analysis of RNA-seq profiles of the purified neuronal subsets revealed 486 and 549 genes differentially expressed in MRGPRD-expressing neurons and C-LTMRs, respectively. We validated 48 MRGPD- and 68 C-LTMRs-enriched genes using a triple-staining approach, and the Cav3.3 channel, found to be exclusively expressed in C-LTMRs, was validated using electrophysiology. Our study greatly expands the molecular characterization of C-LTMRs and suggests that this particular population of neurons shares some molecular features with Aβ and Aδ low-threshold mechanoreceptors.
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Affiliation(s)
- Ana Reynders
- Aix-Marseille-Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France
| | - Annabelle Mantilleri
- Aix-Marseille-Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France
| | - Pascale Malapert
- Aix-Marseille-Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France
| | - Stéphanie Rialle
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Institut de Génomique Fonctionnelle, UMR 5203, CNRS, U1191, INSERM, Université de Montpellier, 141 Rue de la Cardonille, 34094 Montpellier Cedex 05, France
| | - Sabine Nidelet
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Institut de Génomique Fonctionnelle, UMR 5203, CNRS, U1191, INSERM, Université de Montpellier, 141 Rue de la Cardonille, 34094 Montpellier Cedex 05, France
| | - Sophie Laffray
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Institut de Génomique Fonctionnelle, UMR 5203, CNRS, U1191, INSERM, Université de Montpellier, 141 Rue de la Cardonille, 34094 Montpellier Cedex 05, France
| | - Corinne Beurrier
- Aix-Marseille-Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France
| | - Emmanuel Bourinet
- Laboratories of Excellence, Ion Channel Science and Therapeutics, Institut de Génomique Fonctionnelle, UMR 5203, CNRS, U1191, INSERM, Université de Montpellier, 141 Rue de la Cardonille, 34094 Montpellier Cedex 05, France.
| | - Aziz Moqrich
- Aix-Marseille-Université, CNRS, Institut de Biologie du Développement de Marseille, UMR 7288, Case 907, 13288 Marseille Cedex 09, France.
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Bouret S, Levin BE, Ozanne SE. Gene-environment interactions controlling energy and glucose homeostasis and the developmental origins of obesity. Physiol Rev 2015; 95:47-82. [PMID: 25540138 PMCID: PMC4281588 DOI: 10.1152/physrev.00007.2014] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Obesity and type 2 diabetes mellitus (T2DM) often occur together and affect a growing number of individuals in both the developed and developing worlds. Both are associated with a number of other serious illnesses that lead to increased rates of mortality. There is likely a polygenic mode of inheritance underlying both disorders, but it has become increasingly clear that the pre- and postnatal environments play critical roles in pushing predisposed individuals over the edge into a disease state. This review focuses on the many genetic and environmental variables that interact to cause predisposed individuals to become obese and diabetic. The brain and its interactions with the external and internal environment are a major focus given the prominent role these interactions play in the regulation of energy and glucose homeostasis in health and disease.
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Affiliation(s)
- Sebastien Bouret
- The Saban Research Institute, Neuroscience Program, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, California; Inserm U837, Jean-Pierre Aubert Research Center, University Lille 2, Lille, France; Neurology Service, Veterans Administration Medical Center, East Orange, New Jersey; Department of Neurology and Neurosciences, Rutgers, New Jersey Medical School, Newark, New Jersey; and University of Cambridge Institute of Metabolic Science and MRC Metabolic Diseases Unit, Cambridge, United Kingdom
| | - Barry E Levin
- The Saban Research Institute, Neuroscience Program, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, California; Inserm U837, Jean-Pierre Aubert Research Center, University Lille 2, Lille, France; Neurology Service, Veterans Administration Medical Center, East Orange, New Jersey; Department of Neurology and Neurosciences, Rutgers, New Jersey Medical School, Newark, New Jersey; and University of Cambridge Institute of Metabolic Science and MRC Metabolic Diseases Unit, Cambridge, United Kingdom
| | - Susan E Ozanne
- The Saban Research Institute, Neuroscience Program, Childrens Hospital Los Angeles, University of Southern California, Los Angeles, California; Inserm U837, Jean-Pierre Aubert Research Center, University Lille 2, Lille, France; Neurology Service, Veterans Administration Medical Center, East Orange, New Jersey; Department of Neurology and Neurosciences, Rutgers, New Jersey Medical School, Newark, New Jersey; and University of Cambridge Institute of Metabolic Science and MRC Metabolic Diseases Unit, Cambridge, United Kingdom
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Duca FA, Yue JTY. Fatty acid sensing in the gut and the hypothalamus: in vivo and in vitro perspectives. Mol Cell Endocrinol 2014; 397:23-33. [PMID: 25261798 DOI: 10.1016/j.mce.2014.09.022] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/19/2014] [Accepted: 09/19/2014] [Indexed: 12/15/2022]
Abstract
The ability to properly sense both ingested and circulating nutrients is crucial for the maintenance of metabolic homeostasis. As such, both the gastrointestinal tract and the hypothalamus have demonstrated the capacity to sense and effectively respond to nutrients, such as fatty acids, to control food intake and glucose production to regulate energy and glucose homeostasis. In modern, Westernized societies, obesity and diabetes rates continue to rise unabated, due in part to an increase in highly palatable high-fat diet consumption. Thus, our understanding in the ability of the body to successfully monitor lipids is more vital than ever. This review details the current understanding of both the gut and the brain, specifically the hypothalamus, in sensing fatty acids. Highlighting both in vivo and in vitro studies, we explore some of the mechanisms upon which different fatty acids activate enteroendocrine and neural lipid-sensing signaling mechanisms to subsequently lower food intake and glucose production to ultimately regulate metabolic homeostasis. A better understanding of these lipid-sensing pathways could lay the groundwork for successful pharmacological targets for the treatment of obesity and diabetes.
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Affiliation(s)
- Frank A Duca
- Toronto General Research Institute and Department of Medicine, UHN, Toronto, M5G 1L7, Canada
| | - Jessica T Y Yue
- Toronto General Research Institute and Department of Medicine, UHN, Toronto, M5G 1L7, Canada.
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Lo CC, Davidson WS, Hibbard SK, Georgievsky M, Lee A, Tso P, Woods SC. Intraperitoneal CCK and fourth-intraventricular Apo AIV require both peripheral and NTS CCK1R to reduce food intake in male rats. Endocrinology 2014; 155:1700-7. [PMID: 24564397 PMCID: PMC3990852 DOI: 10.1210/en.2013-1846] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Apolipoprotein AIV (Apo AIV) and cholecystokinin (CCK) are secreted in response to fat consumption, and both cause satiation via CCK 1 receptor (CCK-1R)-containing vagal afferent nerves to the nucleus of the solitary tract (NTS), where Apo AIV is also synthesized. Fasted male Long-Evans rats received ip CCK-8 or fourth-ventricular (i4vt) Apo AIV alone or in combination. Food intake and c-Fos proteins (a product of the c-Fos immediate-early gene) were assessed. i4vt Apo AIV and/or ip CCK at effective doses reduced food intake and activated c-Fos proteins in the NTS and hypothalamic arcuate nucleus and paraventricular nucleus. Blockade of the CCK-1R by i4vt lorglumide adjacent to the NTS attenuated the satiating and c-Fos-stimulating effects of CCK and Apo AIV, alone or in combination. Maintenance on a high-fat diet (HFD) for 10 weeks resulted in weight gain and attenuation of both the behavioral and c-Fos responses to a greater extent than occurred in low-fat diet-fed and pair-fed HFD animals. These observations suggest that NTS Apo AIV or/and peripheral CCK requires vagal CCK-1R signaling to elicit satiation and that maintenance on a HFD reduces the satiating capacity of these 2 signals.
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MESH Headings
- Animals
- Apolipoproteins A/administration & dosage
- Apolipoproteins A/genetics
- Apolipoproteins A/metabolism
- Apolipoproteins A/pharmacology
- Appetite Depressants/administration & dosage
- Appetite Depressants/pharmacology
- Appetite Depressants/therapeutic use
- Appetite Regulation/drug effects
- Appetite Stimulants/administration & dosage
- Appetite Stimulants/pharmacology
- Appetitive Behavior/drug effects
- Behavior, Animal/drug effects
- Cholecystokinin/administration & dosage
- Cholecystokinin/analogs & derivatives
- Cholecystokinin/antagonists & inhibitors
- Cholecystokinin/metabolism
- Diet, High-Fat/adverse effects
- Hormone Antagonists/administration & dosage
- Hormone Antagonists/pharmacology
- Infusions, Intraventricular
- Injections, Intraperitoneal
- Male
- Nerve Tissue Proteins/administration & dosage
- Nerve Tissue Proteins/agonists
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/metabolism
- Neurons, Afferent/drug effects
- Neurons, Afferent/metabolism
- Obesity/drug therapy
- Obesity/etiology
- Obesity/metabolism
- Rats
- Rats, Long-Evans
- Receptor, Cholecystokinin A/agonists
- Receptor, Cholecystokinin A/antagonists & inhibitors
- Receptor, Cholecystokinin A/metabolism
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/pharmacology
- Sincalide/administration & dosage
- Sincalide/analogs & derivatives
- Sincalide/pharmacology
- Solitary Nucleus/drug effects
- Solitary Nucleus/metabolism
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Affiliation(s)
- Chunmin C Lo
- Departments of Pathology and Laboratory Medicine (C.C.L., W.S.D., S.K.H., M.G., A.L., P.T.) and Psychiatry and Behavioral Neuroscience (S.C.W.), Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio 45237-0507
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Duca FA, Sakar Y, Covasa M. The modulatory role of high fat feeding on gastrointestinal signals in obesity. J Nutr Biochem 2014; 24:1663-77. [PMID: 24041374 DOI: 10.1016/j.jnutbio.2013.05.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/13/2013] [Accepted: 05/28/2013] [Indexed: 01/03/2023]
Abstract
The gastrointestinal (GI) tract is a specialized sensory system that detects and responds to constant changes in nutrient- and bacterial-derived intestinal signals, thus contributing to controls of food intake. Chronic exposure to dietary fat causes morphological, physiological and metabolic changes leading to disruptions in the regulatory feeding pathways promoting more efficient fat absorption and utilization, blunted satiation signals and excess adiposity. Accumulating evidence demonstrates that impaired gastrointestinal signals following long-term high fat consumption are, at least partially, responsible for increased caloric intake. This review focuses on the role of dietary fat in modulating oral and post-oral chemosensory signaling elements responsible for lipid detection and responses, including changes in sensitivity to satiation signals, such as GLP-1, PYY and CCK and their impact on food intake and weight gain. Furthermore, the influence of the gut microbiota on mechanisms controlling energy regulation in the face of excessive fat exposure will be explored. The profound influence of dietary fats on altering complex regulatory feeding pathways can result in dysregulation of body weight and development of obesity, while restoration or manipulation of satiation signaling may prove an effective tool in prevention and treatment of obesity.
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Affiliation(s)
- Frank A Duca
- INRA, UMR 1319 Micalis, F-78352 Jouy-en-Josas, France; AgroParis Tech, UMR 1319, F-78352 Jouy-en-Josas, France; University Pierre and Marie Curie, 75006 Paris, France
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37
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de Lartigue G. Putative roles of neuropeptides in vagal afferent signaling. Physiol Behav 2014; 136:155-69. [PMID: 24650553 DOI: 10.1016/j.physbeh.2014.03.011] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 02/23/2014] [Accepted: 03/10/2014] [Indexed: 02/06/2023]
Abstract
The vagus nerve is a major pathway by which information is communicated between the brain and peripheral organs. Sensory neurons of the vagus are located in the nodose ganglia. These vagal afferent neurons innervate the heart, the lung and the gastrointestinal tract, and convey information about peripheral signals to the brain important in the control of cardiovascular tone, respiratory tone, and satiation, respectively. Glutamate is thought to be the primary neurotransmitter involved in conveying all of this information to the brain. It remains unclear how a single neurotransmitter can regulate such an extensive list of physiological functions from a wide range of visceral sites. Many neurotransmitters have been identified in vagal afferent neurons and have been suggested to modulate the physiological functions of glutamate. Specifically, the anorectic peptide transmitters, cocaine and amphetamine regulated transcript (CART) and the orexigenic peptide transmitters, melanin concentrating hormone (MCH) are differentially regulated in vagal afferent neurons and have opposing effects on food intake. Using these two peptides as a model, this review will discuss the potential role of peptide transmitters in providing a more precise and refined modulatory control of the broad physiological functions of glutamate, especially in relation to the control of feeding.
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Affiliation(s)
- Guillaume de Lartigue
- Dept Anatomy, Physiology and Cell Biology, UC Davis School of Veterinary Medicine, Davis, CA 95616, USA.
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38
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Abstract
Recent progress in unravelling the nutrient-sensing mechanisms in the taste buds of the tongue has triggered studies on the existence and role of chemosensory cells in the gut. Indeed, the gastrointestinal tract is the key interface between food and the human body and can sense basic tastes in much the same way as the tongue, through the use of similar G-protein-coupled taste receptors. These receptors 'taste' the luminal content and transmit signals that regulate nutrient transporter expression and nutrient uptake, and also the release of gut hormones and neurotransmitters involved in the regulation of energy and glucose homeostasis. Hence, they play a prominent role in the communication between the lumen, epithelium, smooth muscle cells, afferent nerve fibres and the brain to trigger adaptive responses that affect gastrointestinal function, food intake and glucose metabolism. This review summarises how sensing of nutrients by taste receptors along the gut plays a key role in the process of digestion, and how disturbances or adaptations of these chemosensory signalling pathways may contribute to the induction or resolution of a number of pathological conditions related to diabetes, obesity, or diet-induced symptom generation in irritable bowel syndrome. Targeting these receptors may represent a promising novel route for the treatment of a number of these diseases.
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39
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Duca FA, Zhong L, Covasa M. Reduced CCK signaling in obese-prone rats fed a high fat diet. Horm Behav 2013; 64:812-7. [PMID: 24100196 DOI: 10.1016/j.yhbeh.2013.09.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 09/26/2013] [Accepted: 09/29/2013] [Indexed: 11/23/2022]
Abstract
Deficits in satiation signaling during obesogenic feeding have been proposed to play a role in hyperphagia and weight gain in animals prone to become obese. However, whether this impaired signaling is due to high fat (HF) feeding or to their obese phenotype is still unknown. Therefore, in the current study, we examined the effects of CCK-8 (0.5, 1.0, 2.0, and 4.0 μg/kg) on suppression of food intake of HF-fed obese prone (OP) and resistant (OR) rats. Additionally, we determined the role of endogenous CCK in lipid-induced satiation by measuring plasma CCK levels following a lipid gavage, and tested the effect of pretreatment with devazepide, a CCK-1R antagonist on intragastric lipid-induced satiation. Finally, we examined CCK-1R mRNA levels in the nodose ganglia. We show that OP rats have reduced feeding responses to the low doses of exogenous CCK-8 compared to OR rats. Furthermore, OP rats exhibit deficits in endogenous CCK signaling, as pretreatment with devazepide failed to abolish the reduction in food intake following lipid gavage. These effects were associated with reduced plasma CCK after intragastric lipid in OP but not OR rats. Furthermore, HF feeding resulted in downregulation of CCK-1Rs in the nodose ganglia of OP rats. Collectively, these results demonstrate that HF feeding leads to impairments in lipid-induced CCK satiation signaling in obese-prone rats, potentially contributing to hyperphagia and weight gain.
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Affiliation(s)
- Frank A Duca
- UMR1913-MICALIS, INRA, Domaine de Vilvert, Jouy-en-Josas 78352, France; UMR1913-MICALIS, AgroParisTech, Domaine de Vilvert, Jouy-en-Josas, 78352, France; Doctoral School of Physiology and Pathophysiology, University Pierre and Marie Currie, 15 rue de l'Ecole de Médecine, Paris 75006, France
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40
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Cluny NL, Baraboi ED, Mackie K, Burdyga G, Richard D, Dockray GJ, Sharkey KA. High fat diet and body weight have different effects on cannabinoid CB(1) receptor expression in rat nodose ganglia. Auton Neurosci 2013; 179:122-30. [PMID: 24145047 DOI: 10.1016/j.autneu.2013.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 09/20/2013] [Accepted: 09/23/2013] [Indexed: 01/21/2023]
Abstract
Energy balance is regulated, in part, by the orexigenic signaling pathways of the vagus nerve. Fasting-induced modifications in the expression of orexigenic signaling systems have been observed in vagal afferents of lean animals. Altered basal cannabinoid (CB1) receptor expression in the nodose ganglia in obesity has been reported. Whether altered body weight or a high fat diet modifies independent or additive changes in CB1 expression is unknown. We investigated the expression of CB1 and orexin 1 receptor (OX-1R) in the nodose ganglia of rats fed ad libitum or food deprived (24h), maintained on low or high fat diets (HFD), with differing body weights. Male Wistar rats were fed chow or HFD (diet-induced obese: DIO or diet-resistant: DR) or were body weight matched to the DR group but fed chow (wmDR). CB1 and OX-1R immunoreactivity were investigated and CB1 mRNA density was determined using in situ hybridization. CB1 immunoreactivity was measured in fasted rats after sulfated cholecystokinin octapeptide (CCK8s) administration. In chow rats, fasting did not modify the level of CB1 mRNA. More CB1 immunoreactive cells were measured in fed DIO, DR and wmDR rats than chow rats; levels increased after fasting in chow and wmDR rats but not in DIO or DR rats. In HFD fasted rats CCK8s did not reduce CB1 immunoreactivity. OX-1R immunoreactivity was modified by fasting only in DR rats. These data suggest that body weight contributes to the proportion of neurons expressing CB1 immunoreactivity in the nodose ganglion, while HFD blunts fasting-induced increases, and CCK-induced suppression of, CB1-immunoreactivity.
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Affiliation(s)
- N L Cluny
- Hotchkiss Brain Institute, Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
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41
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Breen DM, Rasmussen BA, Côté CD, Jackson VM, Lam TK. Nutrient-sensing mechanisms in the gut as therapeutic targets for diabetes. Diabetes 2013; 62:3005-13. [PMID: 23970519 PMCID: PMC3749331 DOI: 10.2337/db13-0523] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The small intestine is traditionally viewed as an organ that mediates nutrient digestion and absorption. This view has recently been revised owing to the ability of the duodenum to sense nutrient influx and trigger negative feedback loops to inhibit glucose production and food intake to maintain metabolic homeostasis. Further, duodenal nutrient-sensing defects are acquired in diabetes and obesity, leading to increased glucose production. In contrast, jejunal nutrient sensing inhibits glucose production and mediates the early antidiabetic effect of bariatric surgery, and gut microbiota composition may alter intestinal nutrient-sensing mechanisms to regain better control of glucose homeostasis in diabetes and obesity in the long term. This perspective highlights nutrient-sensing mechanisms in the gut that regulate glucose homeostasis and the potential of targeting gut nutrient-sensing mechanisms as a therapeutic strategy to lower blood glucose concentrations in diabetes.
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Affiliation(s)
- Danna M. Breen
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Brittany A. Rasmussen
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Clémence D. Côté
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - V. Margaret Jackson
- Department of Cardiovascular, Metabolic and Endocrine Diseases, Pfizer Global Research and Development, Cambridge, Massachusetts
| | - Tony K.T. Lam
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
- Corresponding author: Tony K.T. Lam,
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42
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Campos CA, Shiina H, Silvas M, Page S, Ritter RC. Vagal afferent NMDA receptors modulate CCK-induced reduction of food intake through synapsin I phosphorylation in adult male rats. Endocrinology 2013; 154:2613-25. [PMID: 23715865 PMCID: PMC3713210 DOI: 10.1210/en.2013-1062] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vagal afferent nerve fibers transmit gastrointestinal satiation signals to the brain via synapses in the nucleus of the solitary tract (NTS). Despite their pivotal role in energy homeostasis, little is known about the cellular mechanisms enabling fleeting synaptic events at vagal sensory endings to sustain behavioral changes lasting minutes to hours. Previous reports suggest that the reduction of food intake by the satiation peptide, cholecystokinin (CCK), requires activation of N-methyl-D-aspartate-type glutamate receptors (NMDAR) in the NTS, with subsequent phosphorylation of ERK1/2 (pERK1/2) in NTS vagal afferent terminals. The synaptic vesicle protein synapsin I is phosphorylated by pERK1/2 at serines 62 and 67. This pERK1/2-catalyzed phosphorylation increases synaptic strength by increasing the readily releasable pool of the neurotransmitter. Conversely, dephosphorylation of serines 62 and 67 by calcineurin reduces the size of the readily releasable transmitter pool. Hence, the balance of synapsin I phosphorylation and dephosphorylation can modulate synaptic strength. We postulated that CCK-evoked activation of vagal afferent NMDARs results in pERK1/2-catalyzed phosphorylation of synapsin I in vagal afferent terminals, leading to the suppression of food intake. We found that CCK injection increased the phosphorylation of synapsin I in the NTS and that this increase is abolished after surgical or chemical ablation of vagal afferent fibers. Furthermore, fourth ventricle injection of an NMDAR antagonist or the mitogen-activated ERK kinase inhibitor blocked CCK-induced synapsin I phosphorylation, indicating that synapsin phosphorylation in vagal afferent terminals depends on NMDAR activation and ERK1/2 phosphorylation. Finally, hindbrain inhibition of calcineurin enhanced and prolonged synapsin I phosphorylation and potentiated reduction of food intake by CCK. Our findings are consistent with a mechanism in which NMDAR-dependent phosphorylation of ERK1/2 modulates satiation signals via synapsin I phosphorylation in vagal afferent endings.
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Affiliation(s)
- Carlos A Campos
- Department of Integrative Physiology and Neuroscience, Washington State University, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA.
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43
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Alén F, Ramírez-López MT, Gómez de Heras R, Rodríguez de Fonseca F, Orio L. Cannabinoid Receptors and Cholecystokinin in Feeding Inhibition. ANOREXIA 2013; 92:165-96. [DOI: 10.1016/b978-0-12-410473-0.00007-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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44
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The Role of Cholecystokinin Receptors in the Short-Term Control of Food Intake. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 114:277-316. [DOI: 10.1016/b978-0-12-386933-3.00008-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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45
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Iwasaki Y, Yada T. Vagal afferents sense meal-associated gastrointestinal and pancreatic hormones: mechanism and physiological role. Neuropeptides 2012; 46:291-7. [PMID: 23020951 DOI: 10.1016/j.npep.2012.08.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 08/17/2012] [Accepted: 08/17/2012] [Indexed: 01/08/2023]
Abstract
Some gastrointestinal and pancreatic hormones are potently secreted by meal intake and reduce food intake, therefore these hormones play a role in the meal-evoked satiety peptides. Previous reports have demonstrated that peripheral administration of these gastrointestinal or pancreatic hormones decrease feeding and the anorectic effects are abolished by lesions of vagal afferent nerves using surgical or chemical protocols, indicative of the involvement of the vagal afferents. Vagal afferent nerves link between several peripheral organs and the nucleus tractus solitarius of the brainstem. The present review focuses on cholecystokinin, peptide YY(3-36), pancreatic polypeptide, and nesfatin-1 released from endocrine cells of the gut and pancreas. These hormonal peptides directly act on and increase cytosolic Ca(2+) in vagal afferent nodose ganglion neurons and finally suppress food intake via vagal afferents. Therefore, peripheral terminals of vagal afferents could sense gastrointestinal and pancreatic hormones and regulate food intake. Here, we review how the vagal afferent neurons sense a variety of gastrointestinal and pancreatic hormones and discuss its physiological significance in regulation of feeding.
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Affiliation(s)
- Yusaku Iwasaki
- Division of Integrative Physiology, Department of Physiology, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
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Mohammad S, Ozaki T, Takeuchi K, Unno K, Yamoto K, Morioka E, Takiguchi S, Ikeda M. Functional compensation between cholecystokinin-1 and -2 receptors in murine paraventricular nucleus neurons. J Biol Chem 2012; 287:39391-401. [PMID: 23038256 PMCID: PMC3501058 DOI: 10.1074/jbc.m112.416214] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/02/2012] [Indexed: 01/11/2023] Open
Abstract
Cholecystokinin (CCK) and its receptor subtypes CCK-1 and -2 have diverse homeostatic functions. CCK-1 and -2 receptors share a common phosphatidylinositol signaling pathway, yet little is known regarding their possible functional coupling. We focused on CCK-mediated Ca(2+) signaling in parvocellular paraventricular nucleus (PVN) cells, which control satiety and other autonomic functions. Analysis of mouse hypothalamic slices demonstrated that the general CCK receptor agonist CCK-8s (10 nM) triggered Ca(2+) transients most significantly in the posterior subregion of the PVN (PaPo). This 10 nM CCK-8s-induced response was absent in CCK-1 receptor knock-out (CCK1R(-/-)) slices, showing that the response is mediated by CCK-1 receptors. CCK-8s concentrations higher than 30 nM triggered a Ca(2+) rise similarly in wild-type and CCK1R(-/-) slices. The large CCK-8s (100 nM)-induced Ca(2+) responses in CCK1R(-/-) slices were blocked by a CCK-2 receptor antagonist (CI-988), whereas those in wild-type slices required a mixture of CI-988 and lorglumide (a CCK-1 receptor antagonist) for complete antagonism. Therefore, CCK-1 and -2 receptors may function synergistically in single PaPo neurons and deletion of CCK-1 receptors may facilitate CCK-2 receptor signaling. This hypothesis was supported by results of real-time RT-PCR, immunofluorescence double labeling and Western blotting assays, which indicated CCK-2 receptor overexpression in PaPo neurons of CCK1R(-/-) mice. Furthermore, behavioral studies showed that intraperitoneal injections of lorglumide up-regulated food accesses in wild-type but not in CCK1R(-/-) mice, whereas CI-988 injections up-regulated food accesses in CCK1R(-/-) but not in wild-type mice. Compensatory CCK signaling via CCK-2 receptors in CCK1R(-/-) mice shed light on currently controversial satiety-controlling mechanisms.
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Affiliation(s)
| | - Tomoya Ozaki
- From the Graduate School of Innovative Life Science and
| | - Kouhei Takeuchi
- the Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama-city, Toyama 930-8555 and
| | - Katsuya Unno
- the Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama-city, Toyama 930-8555 and
| | - Kurumi Yamoto
- the Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama-city, Toyama 930-8555 and
| | - Eri Morioka
- From the Graduate School of Innovative Life Science and
| | - Soichi Takiguchi
- the Institute for Clinical Research, National Kyushu Cancer Center, 3-1-1 Notame, Minami-ku, Fukuoka 811-1395, Japan
| | - Masayuki Ikeda
- From the Graduate School of Innovative Life Science and
- the Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama-city, Toyama 930-8555 and
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47
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Babic T, Troy AE, Fortna SR, Browning KN. Glucose-dependent trafficking of 5-HT3 receptors in rat gastrointestinal vagal afferent neurons. Neurogastroenterol Motil 2012; 24:e476-88. [PMID: 22845622 PMCID: PMC3440531 DOI: 10.1111/j.1365-2982.2012.01987.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Intestinal glucose induces gastric relaxation via vagally mediated sensory-motor reflexes. Glucose can alter the activity of gastrointestinal (GI) vagal afferent (sensory) neurons directly, via closure of ATP-sensitive potassium channels, and indirectly, via the release of 5-hydroxytryptamine (5-HT) from mucosal enteroendocrine cells. We hypothesized that glucose may also be able to modulate the ability of GI vagal afferent neurons to respond to the released 5-HT, via regulation of neuronal 5-HT(3) receptors. METHODS Whole-cell patch clamp recordings were made from acutely dissociated GI-projecting vagal afferent neurons exposed to equiosmolar Krebs' solution containing different concentrations of d-glucose (1.25-20 mmol L(-1)) and the response to picospritz application of 5-HT assessed. The distribution of 5-HT(3) receptors in neurons exposed to different glucose concentrations was also assessed immunohistochemically. KEY RESULTS Increasing or decreasing extracellular d-glucose concentration increased or decreased, respectively, the 5-HT-induced inward current and the proportion of 5-HT(3) receptors associated with the neuronal membrane. These responses were blocked by the Golgi-disrupting agent Brefeldin-A (5 μmol L(-1)) suggesting involvement of a protein-trafficking pathway. Furthermore, l-glucose did not mimic the response of d-glucose implying that metabolic events downstream of neuronal glucose uptake are required to observe the modulation of 5-HT(3) receptor mediated responses. CONCLUSIONS & INFERENCES These results suggest that, in addition to inducing the release of 5-HT from enterochromaffin cells, glucose may also increase the ability of GI vagal sensory neurons to respond to the released 5-HT, providing a means by which the vagal afferent signal can be amplified or prolonged.
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Affiliation(s)
- T Babic
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033, USA
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48
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Page AJ, Symonds E, Peiris M, Blackshaw LA, Young RL. Peripheral neural targets in obesity. Br J Pharmacol 2012; 166:1537-58. [PMID: 22432806 PMCID: PMC3419899 DOI: 10.1111/j.1476-5381.2012.01951.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/20/2012] [Accepted: 02/22/2012] [Indexed: 12/15/2022] Open
Abstract
Interest in pharmacological treatments for obesity that act in the brain to reduce appetite has increased exponentially over recent years, but failures of clinical trials and withdrawals due to adverse effects have so far precluded any success. Treatments that do not act within the brain are, in contrast, a neglected area of research and development. This is despite the fact that a vast wealth of molecular mechanisms exists within the gut epithelium and vagal afferent system that could be manipulated to increase satiety. Here we discuss mechano- and chemosensory pathways from the gut involved in appetite suppression, and distinguish between gastric and intestinal vagal afferent pathways in terms of their basic physiology and activation by enteroendocrine factors. Gastric bypass surgery makes use of this system by exposing areas of the intestine to greater nutrient loads resulting in greater satiety hormone release and reduced food intake. A non-surgical approach to this system is preferable for many reasons. This review details where the opportunities may lie for such approaches by describing nutrient-sensing mechanisms throughout the gastrointestinal tract.
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Affiliation(s)
- Amanda J Page
- Nerve-Gut Research Laboratory, Discipline of Medicine, South Australia, Australia
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49
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Yoshimichi G, Lo CC, Tamashiro KLK, Ma L, Lee DM, Begg DP, Liu M, Sakai RR, Woods SC, Yoshimatsu H, Tso P. Effect of peripheral administration of cholecystokinin on food intake in apolipoprotein AIV knockout mice. Am J Physiol Gastrointest Liver Physiol 2012; 302:G1336-42. [PMID: 22461023 PMCID: PMC3378168 DOI: 10.1152/ajpgi.00325.2010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 03/20/2012] [Indexed: 01/31/2023]
Abstract
Apolipoprotein AIV (apo AIV) and cholecystokinin (CCK) are satiation factors secreted by the small intestine in response to lipid meals. Apo AIV and CCK-8 has an additive effect to suppress food intake relative to apo AIV or CCK-8 alone. In this study, we determined whether CCK-8 (1, 3, or 5 μg/kg ip) reduces food intake in fasted apo AIV knockout (KO) mice as effectively as in fasted wild-type (WT) mice. Food intake was monitored by the DietMax food system. Apo AIV KO mice had significantly reduced 30-min food intake following all doses of CCK-8, whereas WT mice had reduced food intake only at doses of 3 μg/kg and above. Post hoc analysis revealed that the reduction of 10-min and 30-min food intake elicited by each dose of CCK-8 was significantly larger in the apo AIV KO mice than in the WT mice. Peripheral CCK 1 receptor (CCK1R) gene expression (mRNA) in the duodenum and gallbladder of the fasted apo AIV KO mice was comparable to that in WT mice. In contrast, CCK1R mRNA in nodose ganglia of the apo AIV KO mice was upregulated relative to WT animals. Similarly, upregulated CCK1R gene expression was found in the brain stem of apo AIV KO mice by in situ hybridization. Although it is possible that the increased satiating potency of CCK in apo AIV KO mice is mediated by upregulation of CCK 1R in the nodose ganglia and nucleus tractus solitarius, additional experiments are required to confirm such a mechanism.
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Affiliation(s)
- Go Yoshimichi
- Department of Pathology and Laboratory Medicine, University of Cincinnati, OH 45237, USA
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50
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Duca FA, Swartz TD, Sakar Y, Covasa M. Decreased intestinal nutrient response in diet-induced obese rats: role of gut peptides and nutrient receptors. Int J Obes (Lond) 2012; 37:375-81. [PMID: 22546775 DOI: 10.1038/ijo.2012.45] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS Diet-induced obesity (DIO) is an excellent model for examining human obesity comprising both genotypic and environmental (diet) factors. Decreased responsiveness to peripheral satiety signaling may be responsible for the hyperphagia in this model. In this study, we investigated responses to nutrient-induced satiation in outbred DIO and DIO-resistant (DR) rats fed a high-energy/high-fat (HE/HF) diet as well as intestinal satiety peptide content, intestinal nutrient-responsive receptor abundance and vagal anorectic receptor expression. METHODS Outbred DIO and DR rats fed a HE/HF diet were tested for short-term feeding responses following nutrient (glucose and intralipid (IL)) gastric loads. Gene and protein expressions of intestinal satiety peptides and fatty acid-responsive receptors were examined from isolated proximal intestinal epithelial cells and cholecystokinin-1 receptor (CCK-1R) and leptin receptor (LepR) mRNA from the nodose ganglia of DIO and DR animals. RESULTS DIO rats were less responsive to IL- (P<0.05) but not glucose-induced suppression of food intake compared with DR rats. DIO rats exhibited decreased CCK, peptide YY (PYY) and glucagon-like peptide-1 (GLP-1; P<0.05 for each) protein expression compared with DR rats. Also, DIO rats expressed more G-protein-coupled receptor 40 (GPR40; P<0.0001), GPR41 (P<0.001) and GPR120 (P<0.01) relative to DR rats. Finally, there were no differences in mRNA expression for CCK-1R and LepR in the nodose ganglia of DIO and DR rats. CONCLUSIONS Development of DIO may be partly due to decreased fat-induced satiation through low levels of endogenous satiety peptides, and changes in intestinal nutrient receptors.
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Affiliation(s)
- F A Duca
- INRA, Centre de Recherche de Jouy-en-Josas, UMR 1319, MICALIS, Neurobiology of Ingestive Behavior, Domaine de Vilvert, Jouy-en-Josas, France
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