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Mohammed AA, Abo El-Matty DM, Abd ElSalam EA, Hussein MA, Hafez W, Ibrahim SA, Shaheen EAH, Awad EA, Osman MA, Abd El-Raouf MS, Saed SM, El-Amir RY, Ghaith D, Al Anouti F, Wahba AS. Evaluating the Feasibility of Pro-Neurotensin and 25-Hydroxyvitamin D3 as Possible Indicators for Type 2 Diabetes Mellitus and Its Complications. Healthcare (Basel) 2023; 11:healthcare11081088. [PMID: 37107924 PMCID: PMC10138095 DOI: 10.3390/healthcare11081088] [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: 02/14/2023] [Revised: 04/01/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
(1) Background: Type 2 diabetes mellitus (T2DM) and metabolic syndrome are associated with decreased vitamin D. In contrast, high pro-neurotensin (pro-NT) levels are linked with an increased risk of T2DM and cardiovascular disease. We aimed to determine the validity of pro-NT and 25-dihydroxy vitamin D3 levels as predictors for T2DM complications; (2) Methods: One hundred T2DM, and one hundred healthy volunteers participated in this case-control study. Their Pro-NT and 25-hydroxyvitamin D3 levels were evaluated using the ELISA technique; (3) Results: Pro-NT and 25 (OH) vitamin D3 have significant validity and accuracy in T2DM prediction, 84.5%, and 90.5%, respectively (p = 0.001). At a value of <29.5, 25-Hydroxy vitamin D3 showed 88% sensitivity and 93% specificity in predicting T2DM. At a value of >124 Pmol/L, Pro-NT showed 81% sensitivity and 88% specificity in predicting T2DM. At a value of 16.5, 25-Hydroxy vitamin D3 had 78.4% sensitivity and 68.3% specificity in predicting T2DM complications. At a value of >158 pmol/L, Pro-NT predicted T2DM complications with 67.6% sensitivity and 56.0% specificity; (4) Conclusions: 25 (OH) Vit D3 and Pro-NT could identify T2DM patients and predict T2DM complications. More extensive research is required to adequately validate this novel perspective with a large population study.
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Affiliation(s)
- Amal A Mohammed
- Department of Biochemistry and Molecular Biology, National Hepatology and Tropical Medicine Research Institute (NHTMRI), Cairo 11796, Egypt
| | - Dina M Abo El-Matty
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt
| | - Esraa A Abd ElSalam
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt
| | - Mona A Hussein
- Department of Internal Medicine, National Institute of Diabetes and Endocrinology, Cairo 11562, Egypt
| | - Wael Hafez
- Department of Internal Medicine, The National Research Centre, Cairo 11511, Egypt
| | - Sharehan A Ibrahim
- Department of Internal Medicine, Faculty of Medicine, Minia University, Minya 61511, Egypt
| | - Eman A H Shaheen
- Department of Clinical and Chemical Pathology, Faculty of Medicine, Helwan University, Cairo 11795, Egypt
| | - Eman A Awad
- Department of Internal Medicine, Faculty of Medicine for Girls, Al-Azhar University, Cairo 11795, Egypt
| | - Marwa A Osman
- Department of Neurology, Faculty of Medicine for Girls, Al-Azhar University, Cairo 11884, Egypt
| | - Marwa S Abd El-Raouf
- Department of Public Health, Faculty of Medicine, Benha University, Benha 13511, Egypt
| | - Salma M Saed
- Department of Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo 11566, Egypt
| | - Reham Y El-Amir
- Department of Public Health, Faculty of Medicine, Cairo University, Giza 12211, Egypt
| | - Doaa Ghaith
- Department of Clinical and Chemical Pathology Department, Faculty of Medicine, Cairo University, Cairo 11566, Egypt
| | - Fatme Al Anouti
- Department of Health Sciences, College of Natural and Health Sciences, Zayed University, Abu Dhabi 144534, United Arab Emirates
| | - Alaa S Wahba
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Suez Canal University, Ismailia 41522, Egypt
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2
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Bennet L, Fawad A, Struck J, Larsson SL, Bergmann A, Melander O. The effect of a randomised controlled lifestyle intervention on weight loss and plasma proneurotensin. BMC Endocr Disord 2022; 22:264. [PMID: 36316682 PMCID: PMC9620644 DOI: 10.1186/s12902-022-01183-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 10/19/2022] [Indexed: 12/02/2022] Open
Abstract
AIMS Proneurotensin (Pro-NT) is a strong predictor of cardiometabolic disease including type 2 diabetes and obesity, however, the effect of lifestyle change on Pro-NT has not been investigated in this context. Middle Eastern (ME) immigrants represent the largest and fastest growing minority population in Europe and are a high-risk population for obesity and type 2 diabetes. In this randomised controlled lifestyle intervention (RCT) addressing ME immigrants to Sweden where weight-loss was previously studied as the main outcome, as a secondary analysis we aimed to study change in Pro-NT during follow-up and if baseline Pro-NT predicted weight loss. METHODS Immigrants from the Middle East at high risk for type 2 diabetes were invited to participate in this RCT adapted lifestyle intervention of four months' duration. The intervention group (N = 48) received a culturally adapted lifestyle intervention comprising seven group sessions and a cooking class addressing healthier diet and increased physical activity. The control group (N = 44) received treatment as usual with information to improve lifestyle habits on their own. Data assessed using mixed effects regression. OUTCOMES Primary outcome; change in Pro-NT. Secondary outcome; change in BMI in relation to baseline plasma concentration of Pro-NT. RESULTS During the four months follow up, weight was significantly reduced in the intervention (-2.5 kg) compared to the control group (0.8 kg) (β -0.12, 95% CI -0.24 to -0.01, P = 0.028). Pro-NT increased to a significantly greater extent in the intervention compared to the control group during follow up (28.2 vs. 3.5 pmol/L) (β 11.4; 4.8 to 18.02, P < 0.001). Change over time in BMI was associated with baseline Pro-NT (β 0.02; 0.01 to 0.04, P = 0.041). CONCLUSION In consistence with data from surgical weight loss, this RCT paradoxically shows increased levels of Pro-NT during a multifactorial lifestyle intervention resulting in weight loss. Long term studies of Pro-NT following weight loss are needed. TRIAL REGISTRATION This study is a secondary analysis of the RCT trial registered at www. CLINICALTRIALS gov . REGISTRATION NUMBER NCT01420198. Date of registration 19/08/2011. The performance and results of this trial conform to the CONSORT 2010 guidelines.
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Affiliation(s)
- Louise Bennet
- Department of Clinical Sciences, Lund University, Malmö, Sweden.
- Clinical Trial Centre, Clinical Studies Sweden - Forum South, Skåne University Hospital in Lund, Jan Waldenströms gata 35, 205 02, Malmö, Sweden.
| | - Ayesha Fawad
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Metabolic Center, Region Skåne, Malmö, Sweden
| | | | - Sara Lönn Larsson
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Clinical Trial Centre, Clinical Studies Sweden - Forum South, Skåne University Hospital in Lund, Jan Waldenströms gata 35, 205 02, Malmö, Sweden
| | - Andreas Bergmann
- Sphingotec GmbH, Hennigsdorf, Germany
- Waltraut Bergmann Foundation, Hohen Neuendorf, Germany
| | - Olle Melander
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Lund University Diabetes Center, Lund University, Malmö, Sweden
- Department of Internal Medicine, Skåne University Hospital, Malmö, Sweden
- Metabolic Center, Region Skåne, Malmö, Sweden
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3
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Concas MP, Cocca M, Catamo E, Gasparini P, Robino A. Eating disinhibition and food liking are influenced by variants in CAV1 (caveolin 1) gene. Food Qual Prefer 2022. [DOI: 10.1016/j.foodqual.2021.104447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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4
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Ratner C, Shin JH, Dwibedi C, Tremaroli V, Bjerregaard A, Hartmann B, Bäckhed F, Leinninger G, Seeley RJ, Holst B. Anorexia and Fat Aversion Induced by Vertical Sleeve Gastrectomy Is Attenuated in Neurotensin Receptor 1-Deficient Mice. Endocrinology 2021; 162:6311588. [PMID: 34190328 PMCID: PMC8294690 DOI: 10.1210/endocr/bqab130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Indexed: 12/25/2022]
Abstract
Neurotensin (NT) is an anorexic gut hormone and neuropeptide that increases in circulation following bariatric surgery in humans and rodents. We sought to determine the contribution of NT to the metabolic efficacy of vertical sleeve gastrectomy (VSG). To explore a potential mechanistic role of NT in VSG, we performed sham or VSG surgeries in diet-induced obese NT receptor 1 (NTSR1) wild-type and knockout (ko) mice and compared their weight and fat mass loss, glucose tolerance, food intake, and food preference after surgery. NTSR1 ko mice had reduced initial anorexia and body fat loss. Additionally, NTSR1 ko mice had an attenuated reduction in fat preference following VSG. Results from this study suggest that NTSR1 signaling contributes to the potent effect of VSG to initially reduce food intake following VSG surgeries and potentially also on the effects on macronutrient selection induced by VSG. However, maintenance of long-term weight loss after VSG requires signals in addition to NT.
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Affiliation(s)
- Cecilia Ratner
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Correspondence: Cecilia Ratner, University of Copenhagen: Kobenhavns Universitet, Blegdamsvej 3B, 2200, Copenhagen N, Denmark. E-mail:
| | - Jae Hoon Shin
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Chinmay Dwibedi
- Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
- Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden
| | | | - Anette Bjerregaard
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Fredrik Bäckhed
- Wallenberg Laboratory, University of Gothenburg, Gothenburg, Sweden
- Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
- Region Västra Götaland, Sahlgrenska University Hospital, Department of Clinical Physiology, Gothenburg, Sweden
| | - Gina Leinninger
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Randy J Seeley
- Department of Surgery, University of Michigan, Ann Arbor, MI, USA
| | - Birgitte Holst
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Correspondence: Birgitte Holst, University of Copenhagen, Blegdamsvej 3B, 2200 Copenhagen N, Denmark.
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5
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Perez-Bonilla P, Santiago-Colon K, Matasovsky J, Ramirez-Virella J, Khan R, Garver H, Fink G, Dorrance AM, Leinninger GM. Activation of ventral tegmental area neurotensin Receptor-1 neurons promotes weight loss. Neuropharmacology 2021; 195:108639. [PMID: 34116109 DOI: 10.1016/j.neuropharm.2021.108639] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 05/17/2021] [Accepted: 06/03/2021] [Indexed: 01/31/2023]
Abstract
Dopamine (DA) neurons in the ventral tegmental area (VTA) modulate physical activity and feeding behaviors that are disrupted in obesity. Yet, the heterogeneity of VTA DA neurons has hindered determination of which ones might be leveraged to support weight loss. We hypothesized that increased activity in the subset of VTA DA neurons expressing neurotensin receptor-1 (NtsR1) might promote weight loss behaviors. To test this, we used Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to activate VTA NtsR1 neurons in normal weight and diet-induced obese mice. Acute activation of VTA NtsR1 neurons (24hr) significantly decreased body weight in normal weight and obese mice by reducing food intake and increasing physical activity. Moreover, daily activation of VTA NtsR1 neurons in obese mice sustained weight loss over 7 days. Activating VTA NtsR1 neurons also suppressed how much mice worked to obtain sucrose rewards, even when there was high motivation to consume. However, VTA NtsR1 neural activation was not reinforcing, nor did it invoke liabilities associated with whole-body NtsR1 agonism such as anxiety, vasodepressor response or hypothermia. Activating VTA NtsR1 neurons therefore promotes dual behaviors that support weight loss without causing adverse effects, and is worth further exploration for managing obesity.
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Affiliation(s)
- Patricia Perez-Bonilla
- Neuroscience Graduate Program, Michigan State University, East Lansing, MI, 48114, USA; Department of Pharmacology and Toxicology, East Lansing, MI, 48114, USA
| | | | - Jillian Matasovsky
- Department of Physiology and College of Natural Science, Michigan State University, East Lansing, MI, 48114, USA
| | - Jariel Ramirez-Virella
- Neuroscience Graduate Program, Michigan State University, East Lansing, MI, 48114, USA; Department of Pharmacology and Toxicology, East Lansing, MI, 48114, USA
| | - Rabail Khan
- Neuroscience Graduate Program, Michigan State University, East Lansing, MI, 48114, USA
| | - Hannah Garver
- Department of Pharmacology and Toxicology, East Lansing, MI, 48114, USA
| | - Gregory Fink
- Department of Pharmacology and Toxicology, East Lansing, MI, 48114, USA; College of Osteopathic Medicine, East Lansing, MI, 48114, USA
| | - Anne M Dorrance
- Department of Pharmacology and Toxicology, East Lansing, MI, 48114, USA; College of Osteopathic Medicine, East Lansing, MI, 48114, USA
| | - Gina M Leinninger
- Department of Physiology and College of Natural Science, Michigan State University, East Lansing, MI, 48114, USA.
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6
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Lu VB, Gribble FM, Reimann F. Nutrient-Induced Cellular Mechanisms of Gut Hormone Secretion. Nutrients 2021; 13:nu13030883. [PMID: 33803183 PMCID: PMC8000029 DOI: 10.3390/nu13030883] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/27/2021] [Accepted: 03/05/2021] [Indexed: 02/06/2023] Open
Abstract
The gastrointestinal tract can assess the nutrient composition of ingested food. The nutrient-sensing mechanisms in specialised epithelial cells lining the gastrointestinal tract, the enteroendocrine cells, trigger the release of gut hormones that provide important local and central feedback signals to regulate nutrient utilisation and feeding behaviour. The evidence for nutrient-stimulated secretion of two of the most studied gut hormones, glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), along with the known cellular mechanisms in enteroendocrine cells recruited by nutrients, will be the focus of this review. The mechanisms involved range from electrogenic transporters, ion channel modulation and nutrient-activated G-protein coupled receptors that converge on the release machinery controlling hormone secretion. Elucidation of these mechanisms will provide much needed insight into postprandial physiology and identify tractable dietary approaches to potentially manage nutrition and satiety by altering the secreted gut hormone profile.
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7
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Wölk E, Stengel A, Schaper SJ, Rose M, Hofmann T. Neurotensin and Xenin Show Positive Correlations With Perceived Stress, Anxiety, Depressiveness and Eating Disorder Symptoms in Female Obese Patients. Front Behav Neurosci 2021; 15:629729. [PMID: 33664656 PMCID: PMC7921165 DOI: 10.3389/fnbeh.2021.629729] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 01/28/2021] [Indexed: 12/25/2022] Open
Abstract
Objective Neurotensin and xenin are two closely related anorexigenic neuropeptides synthesized in the small intestine that exert diverse peripheral and central functions. Both act via the neurotensin-1-receptor. In animal models of obesity reduced central concentrations of these peptides have been found. Dysregulations of the acute and chronic stress response are associated with development and maintenance of obesity. Until now, associations of both peptides with stress, anxiety, depressiveness, and eating disorder symptoms have not been investigated. The aim of the present study was to examine associations of neurotensin and xenin with these psychological characteristics under conditions of obesity. Materials and Methods From 2010 to 2016 we consecutively enrolled 160 inpatients (63 men and 97 women), admitted due to obesity and its mental and somatic comorbidities. Blood withdrawal und psychometric tests (PSQ-20, GAD-7, PHQ-9, and EDI-2) occurred within one week after admission. We measured levels of neurotensin and xenin in plasma by ELISA. Results Mean body mass index was 47.2 ± 9.5 kg/m2. Concentrations of neurotensin and xenin positively correlated with each other (women: r = 0.788, p < 0.001; men: r = 0.731, p < 0.001) and did not significantly differ between sexes (p > 0.05). Women generally displayed higher psychometric values than men (PSQ-20: 58.2 ± 21.7 vs. 47.0 ± 20.8, p = 0.002; GAD-7: 9.7 ± 5.8 vs. 7.1 ± 5.3, p = 0.004; PHQ-9: 11.6 ± 6.6 vs. 8.8 ± 5.9, p = 0.008; EDI-2: 50.5 ± 12.8 vs. 39.7 ± 11.9, p < 0.001). Only women showed positive correlations of both neuropeptides with stress (neurotensin: r = 0.231, p = 0.023; xenin: r = 0.254, p = 0.013), anxiety (neurotensin: r = 0.265, p = 0.009; xenin: r = 0.257, p = 0.012), depressiveness (neurotensin: r = 0.281, p = 0.006; xenin: r = 0.241, p = 0.019) and eating disorder symptoms (neurotensin: r = 0.276, p = 0.007; xenin: r = 0.26, p = 0.011), whereas, men did not (p > 0.05). Conclusion Neurotensin and xenin plasma levels of female obese patients are positively correlated with perceived stress, anxiety, depressiveness, and eating disorder symptoms. These associations could be influenced by higher prevalence of mental disorders in women and by sex hormones. In men, no correlations were observed, which points toward a sex-dependent regulation.
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Affiliation(s)
- Ellen Wölk
- Department for Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Andreas Stengel
- Department for Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Department of Psychosomatic Medicine and Psychotherapy, University Hospital Tübingen, Tübingen, Germany
| | - Selina Johanna Schaper
- Department for Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Matthias Rose
- Department for Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Tobias Hofmann
- Department for Psychosomatic Medicine, Charité Center for Internal Medicine and Dermatology, Corporate Member of Freie Universität Berlin, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
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8
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Gobron B, Bouvard B, Vyavahare S, Blom LV, Pedersen KK, Windeløv JA, Boer GA, Harada N, Zhang S, Shimazu-Kuwahara S, Wice B, Inagaki N, Legrand E, Flatt PR, Chappard D, Hartmann B, Holst JJ, Rosenkilde MM, Irwin N, Mabilleau G. Enteroendocrine K Cells Exert Complementary Effects to Control Bone Quality and Mass in Mice. J Bone Miner Res 2020; 35:1363-1374. [PMID: 32155286 DOI: 10.1002/jbmr.4004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/27/2020] [Accepted: 03/04/2020] [Indexed: 12/11/2022]
Abstract
The involvement of a gut-bone axis in controlling bone physiology has been long suspected, although the exact mechanisms are unclear. We explored whether glucose-dependent insulinotropic polypeptide (GIP)-producing enteroendocrine K cells were involved in this process. The bone phenotype of transgenic mouse models lacking GIP secretion (GIP-GFP-KI) or enteroendocrine K cells (GIP-DT) was investigated. Mice deficient in GIP secretion exhibited lower bone strength, trabecular bone mass, trabecular number, and cortical thickness, notably due to higher bone resorption. Alterations of microstructure, modifications of bone compositional parameters, represented by lower collagen cross-linking, were also apparent. None of these alterations were observed in GIP-DT mice lacking enteroendocrine K cells, suggesting that another K-cell secretory product acts to counteract GIP action. To assess this, stable analogues of the known K-cell peptide hormones, xenin and GIP, were administered to mature NIH Swiss male mice. Both were capable of modulating bone strength mostly by altering bone microstructure, bone gene expression, and bone compositional parameters. However, the two molecules exhibited opposite actions on bone physiology, with evidence that xenin effects are mediated indirectly, possibly via neural networks. Our data highlight a previously unknown interaction between GIP and xenin, which both moderate gut-bone connectivity. © 2020 American Society for Bone and Mineral Research.
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Affiliation(s)
- Benoît Gobron
- Groupe Études Remodelage Osseux et Biomatériaux, GEROM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Service de Rhumatologie, CHU d'Angers, Angers, France
| | - Béatrice Bouvard
- Groupe Études Remodelage Osseux et Biomatériaux, GEROM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Service de Rhumatologie, CHU d'Angers, Angers, France
| | - Sagar Vyavahare
- School of Biomedical Sciences, University of Ulster, Coleraine, UK
| | - Liv Vv Blom
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristian K Pedersen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Johanne A Windeløv
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Geke A Boer
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Norio Harada
- Department of Diabetes, Endocrinology, and Nutrition, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Sheng Zhang
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO, USA
| | - Satoko Shimazu-Kuwahara
- Department of Diabetes, Endocrinology, and Nutrition, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Burton Wice
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO, USA
| | - Nobuya Inagaki
- Department of Diabetes, Endocrinology, and Nutrition, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Erick Legrand
- Groupe Études Remodelage Osseux et Biomatériaux, GEROM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Service de Rhumatologie, CHU d'Angers, Angers, France
| | - Peter R Flatt
- School of Biomedical Sciences, University of Ulster, Coleraine, UK
| | - Daniel Chappard
- Groupe Études Remodelage Osseux et Biomatériaux, GEROM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Service Commun D'imageries et d'Analyses Microscopiques, SCIAM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Bone Pathology Unit, CHU d'Angers, Angers, France
| | - Bolette Hartmann
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Novo Nordisk Foundation Center for Basic Metabolic Research, University of Copenhagen, Copenhagen, Denmark
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nigel Irwin
- School of Biomedical Sciences, University of Ulster, Coleraine, UK
| | - Guillaume Mabilleau
- Groupe Études Remodelage Osseux et Biomatériaux, GEROM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Service Commun D'imageries et d'Analyses Microscopiques, SCIAM, SFR 42-08, Université d'Angers, Institut de Biologie en Santé, CHU d'Angers, Angers, France.,Bone Pathology Unit, CHU d'Angers, Angers, France
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9
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Novel stable analogues of the neurotensin C-terminal hexapeptide containing unnatural amino acids. Amino Acids 2019; 51:1009-1022. [DOI: 10.1007/s00726-019-02741-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 05/02/2019] [Indexed: 10/26/2022]
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10
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Kerbel B, Badal K, Sundarrajan L, Blanco A, Unniappan S. Xenin is a novel anorexigen in goldfish (Carassius auratus). PLoS One 2018; 13:e0197817. [PMID: 29791497 PMCID: PMC5965858 DOI: 10.1371/journal.pone.0197817] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/09/2018] [Indexed: 12/13/2022] Open
Abstract
Xenin, a highly conserved 25 amino acid peptide cleaved from the N-terminus of the coatomer protein alpha (COPA), is emerging as a food intake regulator in mammals and birds. To date, no research has been conducted on xenin biology in fish. This study aims to identify the copa mRNA encoding xenin in goldfish (Carassius auratus) as a model, to elucidate its regulation by feeding, and to describe the role of xenin on appetite. First, a partial sequence of copa cDNA, a region encoding xenin, was identified from goldfish brain. This sequence is highly conserved among both vertebrates and invertebrates. RT-qPCR revealed that copa mRNAs are widely distributed in goldfish tissues, with the highest levels detected in the brain, gill, pituitary and J-loop. Immunohistochemistry confirmed also the presence of COPA peptide in the hypothalamus and enteroendocrine cells on the J-loop mucosa. In line with its anorexigenic effects, we found important periprandial fluctuations in copa mRNA expression in the hypothalamus, which were mainly characterized by a gradually decrease in copa mRNA levels as the feeding time was approached, and a gradual increase after feeding. Additionally, fasting differently modulated the expression of copa mRNA in a tissue-dependent manner. Peripheral and central injections of xenin reduce food intake in goldfish. This research provides the first report of xenin in fish, and shows that this peptide is a novel anorexigen in goldfish.
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Affiliation(s)
- Brent Kerbel
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Kimberly Badal
- Department of Biology, York University, Toronto, Ontario, Canada
| | - Lakshminarasimhan Sundarrajan
- Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Ayelen Blanco
- Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Suraj Unniappan
- Laboratory of Integrative Neuroendocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- * E-mail:
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11
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Woodworth HL, Brown JA, Batchelor HM, Bugescu R, Leinninger GM. Determination of neurotensin projections to the ventral tegmental area in mice. Neuropeptides 2018; 68:57-74. [PMID: 29478718 PMCID: PMC5906039 DOI: 10.1016/j.npep.2018.02.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/11/2018] [Accepted: 02/11/2018] [Indexed: 12/15/2022]
Abstract
Pharmacologic treatment with the neuropeptide neurotensin (Nts) modifies motivated behaviors such as feeding, locomotor activity, and reproduction. Dopamine (DA) neurons of the ventral tegmental area (VTA) control these behaviors, and Nts directly modulates the activity of DA neurons via Nts receptor-1. While Nts sources to the VTA have been described in starlings and rats, the endogenous sources of Nts to the VTA of mice remain incompletely understood, impeding determination of which Nts circuits orchestrate specific behaviors in this model. To overcome this obstacle we injected the retrograde tracer Fluoro-Gold into the VTA of mice that express GFP in Nts neurons. Identification of GFP-Nts cells that accumulate Fluoro-Gold revealed the Nts afferents to the VTA in mice. Similar to rats, most Nts afferents to the VTA of mice arise from the medial and lateral preoptic areas (POA) and the lateral hypothalamic area (LHA), brain regions that are critical for coordination of feeding and reproduction. Additionally, the VTA receives dense input from Nts neurons in the nucleus accumbens shell (NAsh) of mice, and minor Nts projections from the amygdala and periaqueductal gray area. Collectively, our data reveal multiple populations of Nts neurons that provide direct afferents to the VTA and which may regulate specific aspects of motivated behavior. This work lays the foundation for understanding endogenous Nts actions in the VTA, and how circuit-specific Nts modulation may be useful to correct motivational and affective deficits in neuropsychiatric disease.
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Affiliation(s)
| | - Juliette A Brown
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Hannah M Batchelor
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Raluca Bugescu
- Department of Physiology, Michigan State University, East Lansing, MI, USA
| | - Gina M Leinninger
- Department of Physiology, Michigan State University, East Lansing, MI, USA.
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12
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Abstract
Xenin is a gastrointestinal hormone that belongs to the neurotensin family. Central administration of xenin to obese mice reduces food intake and body weight gain and causes alterations in the expression of lipid metabolism-related genes and proteins in white adipose tissue (WAT). However, it has not been tested whether or not xenin directly acts on adipose tissue and alters lipid metabolism. The present study was performed to address this possibility by examining the effect of xenin treatment on the levels of glycerol and free fatty acids (FFA) and expression levels of lipolysis marker proteins ex vivo in cultured mouse WAT. Xenin treatment significantly increased concentrations of glycerol and FFA in culture media and increased phosphorylation of hormone sensitive lipase (HSL) in ex vivo cultured WAT. These findings support the hypothesis that xenin directly acts on adipose tissues and stimulates lipolysis. Thus, enhancement of xenin action and its downstream signaling may offer a novel and effective therapy for obese patients by reducing the amount of stored fat in adipose tissue.
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13
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Maryanovich AT, Kormilets DY, Polyanovsky AD. Xenin: the oldest after insulin? Mol Biol Rep 2018; 45:143-150. [PMID: 29340900 DOI: 10.1007/s11033-018-4147-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 01/10/2018] [Indexed: 11/25/2022]
Abstract
Xenin is a regulatory peptide first isolated from the human gastric mucosa. Using an open-access protein database MEDLINE (33 million molecules; 11 billion amino acid residues) and our original computer program, we conducted a search for the xenin motifs in the primary structure of proteins across almost the entire taxonomic range of evolution. Motifs with 40% homology to human xenin are already present in prokaryotes. Homology reaches 84-96% in single-cell algae and plants, becoming complete since bony fishes. We suppose that this regulatory peptide is more ancient and significant than is usually thought.
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Affiliation(s)
| | | | - Andrey D Polyanovsky
- Sechenov Institute of Evolutionary Physiology and Biochemistry, St. Petersburg, Russia
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14
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Abstract
The maintenance of the body weight at a stable level is a major determinant in keeping the higher animals and mammals survive. Th e body weight depends on the balance between the energy intake and energy expenditure. Increased food intake over the energy expenditure of prolonged time period results in an obesity. Th e obesity has become an important worldwide health problem, even at low levels. The obesity has an evil effect on the health and is associated with a shorter life expectancy. A complex of central and peripheral physiological signals is involved in the control of the food intake. Centrally, the food intake is controlled by the hypothalamus, the brainstem, and endocannabinoids and peripherally by the satiety and adiposity signals. Comprehension of the signals that control food intake and energy balance may open a new therapeutic approaches directed against the obesity and its associated complications, as is the insulin resistance and others. In conclusion, the present review summarizes the current knowledge about the complex system of the peripheral and central regulatory mechanisms of food intake and their potential therapeutic implications in the treatment of obesity.
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Bhavya S, Lew PS, Mizuno TM. Central action of xenin affects the expression of lipid metabolism-related genes and proteins in mouse white adipose tissue. Neuropeptides 2017; 63:67-73. [PMID: 28190525 DOI: 10.1016/j.npep.2017.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/17/2016] [Accepted: 01/06/2017] [Indexed: 12/18/2022]
Abstract
Xenin is a gastrointestinal hormone that reduces food intake when administered centrally and it has been hypothesized that central action of xenin participates in the regulation of whole-body metabolism. The present study was performed to address this hypothesis by investigating the central effect of xenin on the expression of genes and proteins that are involved in the regulation of lipid metabolism in white adipose tissue (WAT). Male obese ob/ob mice received intracerebroventricular (i.c.v.) injections of xenin (5μg) twice 12h apart. Food intake and body weight change during a 24-h period after the first injection were measured. Epididymal WAT was collected at the end of the 24-h treatment period and levels of lipid metabolism-related genes and proteins were measured. Xenin treatment caused significant reductions in food intake and body weight compared to control vehicle treatment. Levels of fatty acid synthase (FASN) protein were significantly reduced by xenin treatment, while levels of adipose triglyceride lipase (Atgl) and beta-3 adrenergic receptor (Adrb3) mRNA and phosphorylated hormone sensitive lipase (Ser660-pHSL and Ser563-pHSL) were significantly increased by xenin treatment. These findings suggest that central action of xenin causes alterations in lipid metabolism in adipose tissue toward reduced lipogenesis and increased lipolysis, possibly contributing to xenin-induced body weight reduction. Thus, enhancing central action of xenin and its downstream targets may be possible targets for the treatment of obesity by reducing the amount of stored fat in adipose tissue.
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Affiliation(s)
- Sharma Bhavya
- Division of Endocrinology and Metabolic Disease, Department of Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Pei San Lew
- Division of Endocrinology and Metabolic Disease, Department of Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Tooru M Mizuno
- Division of Endocrinology and Metabolic Disease, Department of Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada.
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16
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Vallöf D, Ulenius L, Egecioglu E, Engel JA, Jerlhag E. Central administration of the anorexigenic peptide neuromedin U decreases alcohol intake and attenuates alcohol-induced reward in rodents. Addict Biol 2017; 22:640-651. [PMID: 26769653 PMCID: PMC6680249 DOI: 10.1111/adb.12355] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 10/26/2015] [Accepted: 12/01/2015] [Indexed: 01/24/2023]
Abstract
By investigating the neurochemical mechanisms through which alcohol activates the brain reward systems, novel treatment strategies for alcohol use disorder (AUD), a chronic relapsing disease, can be developed. In contrast to the common view of the function of gut-brain peptides, such as neuromedin U (NMU), to regulate food intake and appetite, a novel role in reinforcement mediation has been implied. The anorexigenic effects of NMU are mediated via NMU2 receptors, preferably in the arcuate nucleus and paraventricular nucleus. The expression of NMU2 receptors is also expressed in several reward-related areas in the brain, suggesting a role in reward regulation. The present experiments were therefore set up to investigate the effect of intracerebroventricular administration of NMU on alcohol-mediated behaviors in rodents. We found that central administration of NMU attenuated alcohol-induced locomotor stimulation, accumbal dopamine release and the expression of conditioned place preference in mice. In addition, NMU dose dependently decreased alcohol intake in high, but not in low, alcohol-consuming rats. Central NMU administration did not alter the blood alcohol concentrations nor change the corticosterone levels in rodents. Given that AUD is a major health-care challenge causing an enormous cost to society and novel treatment strategies are warranted, our data suggest that NMU analogues deserve to be evaluated as novel treatment of AUD in humans.
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Affiliation(s)
- Daniel Vallöf
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Lisa Ulenius
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Emil Egecioglu
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Jörgen A. Engel
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
| | - Elisabet Jerlhag
- Department of Pharmacology, Institute of Neuroscience and PhysiologyThe Sahlgrenska Academy at the University of GothenburgGothenburgSweden
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17
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Sterl K, Wang S, Oestricker L, Wallendorf MJ, Patterson BW, Reeds DN, Wice BM. Metabolic responses to xenin-25 are altered in humans with Roux-en-Y gastric bypass surgery. Peptides 2016; 82:76-84. [PMID: 27288245 PMCID: PMC4958565 DOI: 10.1016/j.peptides.2016.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/02/2016] [Accepted: 06/07/2016] [Indexed: 12/25/2022]
Abstract
Xenin-25 (Xen) is a neurotensin-related peptide secreted by a subset of enteroendocrine cells located in the proximal small intestine. Many effects of Xen are mediated by neurotensin receptor-1 on neurons. In healthy humans with normal glucose tolerance (NGT), Xen administration causes diarrhea and inhibits postprandial glucagon-like peptide-1 (GLP-1) release but not insulin secretion. This study determines (i) if Xen has similar effects in humans with Roux-en-Y gastric bypass (RYGB) and (ii) whether neural pathways potentially mediate effects of Xen on glucose homeostasis. Eight females with RYGB and no history of type 2 diabetes received infusions with 0, 4 or 12pmol Xen/kg/min with liquid meals on separate occasions. Plasma glucose and gastrointestinal hormone levels were measured and insulin secretion rates calculated. Pancreatic polypeptide and neuropeptide Y levels were surrogate markers for parasympathetic input to islets and sympathetic tone, respectively. Responses were compared to those in well-matched non-surgical participants with NGT from our earlier study. Xen similarly increased pancreatic polypeptide and neuropeptide Y responses in patients with and without RYGB. In contrast, the ability of Xen to inhibit GLP-1 release and cause diarrhea was severely blunted in patients with RYGB. With RYGB, Xen had no statistically significant effect on glucose, insulin secretory, GLP-1, glucose-dependent insulinotropic peptide, and glucagon responses. However, insulin and glucose-dependent insulinotropic peptide secretion preceded GLP-1 release suggesting circulating GLP-1 does not mediate exaggerated insulin release after RYGB. Thus, Xen has unmasked neural circuits to the distal gut that inhibit GLP-1 secretion, cause diarrhea, and are altered by RYGB.
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Affiliation(s)
- Karin Sterl
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO 63110
| | - Songyan Wang
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO 63110
| | - Lauren Oestricker
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO 63110
| | - Michael J Wallendorf
- Department of Internal Medicine, Divsion of Biostatistics, Washington University School of Medicine, Saint Louis, MO 63110
| | - Bruce W Patterson
- Department of Internal Medicine, Division of Nutritional Science, Washington University School of Medicine, Saint Louis, MO 63110
| | - Dominic N Reeds
- Department of Internal Medicine, Division of Nutritional Science, Washington University School of Medicine, Saint Louis, MO 63110
| | - Burton M Wice
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO 63110
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18
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Kim ER, Lew PS, Spirkina A, Mizuno TM. Xenin-induced feeding suppression is not mediated through the activation of central extracellular signal-regulated kinase signaling in mice. Behav Brain Res 2016; 312:118-26. [PMID: 27316340 DOI: 10.1016/j.bbr.2016.06.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 06/09/2016] [Accepted: 06/13/2016] [Indexed: 10/21/2022]
Abstract
Xenin is a gut hormone that reduces food intake by partly acting through the hypothalamus via neurotensin receptor 1 (Ntsr1). However, specific signaling pathways that mediate xenin-induced feeding suppression are not fully understood. Activation of Ntsr1 leads to the activation of the extracellular signal-regulated kinase (ERK). Hypothalamic ERK participates in the regulation of food intake by mediating the effect of hormonal signals. Therefore, we hypothesized that the anorectic effect of xenin is mediated by hypothalamic ERK signaling. To address this hypothesis, we compared levels of phosphorylation of ERK1/2 (pERK1/2) in the hypothalamus of both control and xenin-treated mice. The effect of xenin on ERK1/2 phosphorylation was also examined in mouse hypothalamic neuronal cell lines with or without Ntsr1. We also examined the effect of the blockade of central ERK signaling on xenin-induced feeding suppression in mice. The intraperitoneal (i.p.) injection of xenin caused a significant increase in the number of pERK1/2-immunoreactive cells in the hypothalamic arcuate nucleus. The majority of pERK1/2-positive cells expressed neuronal nuclei (NeuN), a marker for neurons. Xenin treatment increased pERK1/2 levels in one cell line expressing Ntsr1 but not another line without Ntsr1 expression. Both i.p. and intracerebroventricular (i.c.v.) injections of xenin reduced food intake in mice. The i.c.v. pre-treatment with U0126, a selective inhibitor of ERK1/2 upstream kinases, did not affect xenin-induced reduction in food intake. These findings suggest that although xenin activates ERK signaling in subpopulations of hypothalamic neurons, xenin does not require the activation of hypothalamic ERK signaling pathway to elicit feeding suppression.
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Affiliation(s)
- Eun Ran Kim
- Division of Endocrinology & Metabolic Disease, Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada
| | - Pei San Lew
- Division of Endocrinology & Metabolic Disease, Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada
| | - Alexandra Spirkina
- Division of Endocrinology & Metabolic Disease, Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada
| | - Tooru M Mizuno
- Division of Endocrinology & Metabolic Disease, Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, MB, Canada.
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19
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Chowdhury S, Wang S, Dunai J, Kilpatrick R, Oestricker LZ, Wallendorf MJ, Patterson BW, Reeds DN, Wice BM. Hormonal Responses to Cholinergic Input Are Different in Humans with and without Type 2 Diabetes Mellitus. PLoS One 2016; 11:e0156852. [PMID: 27304975 PMCID: PMC4909255 DOI: 10.1371/journal.pone.0156852] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/20/2016] [Indexed: 12/14/2022] Open
Abstract
Peripheral muscarinic acetylcholine receptors regulate insulin and glucagon release in rodents but their importance for similar roles in humans is unclear. Bethanechol, an acetylcholine analogue that does not cross the blood-brain barrier, was used to examine the role of peripheral muscarinic signaling on glucose homeostasis in humans with normal glucose tolerance (NGT; n = 10), impaired glucose tolerance (IGT; n = 11), and type 2 diabetes mellitus (T2DM; n = 9). Subjects received four liquid meal tolerance tests, each with a different dose of oral bethanechol (0, 50, 100, or 150 mg) given 60 min before a meal containing acetaminophen. Plasma pancreatic polypeptide (PP), glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), glucose, glucagon, C-peptide, and acetaminophen concentrations were measured. Insulin secretion rates (ISRs) were calculated from C-peptide levels. Acetaminophen and PP concentrations were surrogate markers for gastric emptying and cholinergic input to islets. The 150 mg dose of bethanechol increased the PP response 2-fold only in the IGT group, amplified GLP-1 release in the IGT and T2DM groups, and augmented the GIP response only in the NGT group. However, bethanechol did not alter ISRs or plasma glucose, glucagon, or acetaminophen concentrations in any group. Prior studies showed infusion of xenin-25, an intestinal peptide, delays gastric emptying and reduces GLP-1 release but not ISRs when normalized to plasma glucose levels. Analysis of archived plasma samples from this study showed xenin-25 amplified postprandial PP responses ~4-fold in subjects with NGT, IGT, and T2DM. Thus, increasing postprandial cholinergic input to islets augments insulin secretion in mice but not humans. Trial Registration: ClinicalTrials.gov NCT01434901
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Affiliation(s)
- Sara Chowdhury
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Songyan Wang
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Judit Dunai
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Rachel Kilpatrick
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Lauren Z. Oestricker
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Michael J. Wallendorf
- Division of Biostatistics, Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Bruce W. Patterson
- Department of Internal Medicine, Division of Nutritional Science, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Dominic N. Reeds
- Department of Internal Medicine, Division of Nutritional Science, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
| | - Burton M. Wice
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research Washington University School of Medicine, Saint Louis, MO, United States of America
- * E-mail:
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20
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Feifel D, Shilling PD, Fazlinejad AA, Melendez G. Antipsychotic drug-like facilitation of latent inhibition by a brain-penetrating neurotensin-1 receptor agonist. J Psychopharmacol 2016; 30:312-7. [PMID: 26783230 DOI: 10.1177/0269881115625360] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Latent inhibition (LI) is a measure of cognitive gating and refers to reduced conditioned learning when there is pre-exposure to the conditioned stimulus (CS) before it is paired with the unconditioned stimulus (US). Dysregulation of LI is associated with some neuropsychiatric disorders, including schizophrenia, and the ability to facilitate LI in rodents is a reasonably good predictive test for antipsychotic drugs. Converging evidence supports neurotensin-1 receptor (NTS1) agonists as novel drugs for schizophrenia. Therefore, we investigated the ability of a brain-penetrating, selective NTS1 agonist, PD149163, to facilitate LI in heterozygous Brattleboro rats, a strain that exhibits naturally low LI. Conditioned taste aversion to flavored water (FW; 0.1% saccharin) was induced by pairing it with malaise-inducing injections of lithium chloride (LiCl). Prior to LiCl-FW pairing, rats received subcutaneous injections of saline, or PD149163 (100 µg/kg or 200 µg/kg). Half the rats in each drug group had been allowed to drink FW the day before the LiCl-FW pairing (pre-exposed rats). Two days after pairing, the amount of FW each rat consumed was recorded. LI, defined as significantly greater FW drinking in the pre-exposed group compared with the non pre-exposed group, was exhibited only among rats that received 200 µg/kg of PD149163. These results further support NTS1 agonists as potentially novel drugs for the treatment of schizophrenia.
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Affiliation(s)
- D Feifel
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - P D Shilling
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - A A Fazlinejad
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - G Melendez
- Department of Psychiatry, University of California, San Diego, CA, USA
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21
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Posovszky C, Wabitsch M. Regulation of appetite, satiation, and body weight by enteroendocrine cells. Part 1: characteristics of enteroendocrine cells and their capability of weight regulation. Horm Res Paediatr 2015; 83:1-10. [PMID: 25471008 DOI: 10.1159/000368898] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 09/23/2014] [Indexed: 11/19/2022] Open
Abstract
The gastrointestinal tract is the gateway for food in our body. Food ingestion and the ensuing digestive processes depend on the composition and amount of ingested nutrients. This complex process of nutrient digestion and absorption is effectively regulated by the enteroendocrine system. Enteroendocrine cells (EECs) reside scattered throughout the intestinal epithelium. They express nutrient receptors that face the lumen and secrete peptide hormones in response to food. Besides regulating digestion, gastrointestinal endocrine cells are involved in the regulation of appetite and satiety. The first part of this review describes the anatomical and biological characteristics of EECs and discusses the capability of their hormones to influence appetite, satiety, and body weight. In the second part, we then discuss the therapeutic potential of EECs in the treatment of obesity.
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Affiliation(s)
- Carsten Posovszky
- University Outpatient Clinic for Pediatric Gastroenterology, and Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany
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22
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Zhang S, Wang S, Puhl MD, Jiang X, Hyrc KL, Laciny E, Wallendorf MJ, Pappan KL, Coyle JT, Wice BM. Global biochemical profiling identifies β-hydroxypyruvate as a potential mediator of type 2 diabetes in mice and humans. Diabetes 2015; 64:1383-94. [PMID: 25368100 PMCID: PMC4375086 DOI: 10.2337/db14-1188] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 are incretins secreted by respective K and L enteroendocrine cells after eating and amplify glucose-stimulated insulin secretion (GSIS). This amplification has been termed the "incretin response." To determine the role(s) of K cells for the incretin response and type 2 diabetes mellitus (T2DM), diphtheria toxin-expressing (DT) mice that specifically lack GIP-producing cells were backcrossed five to eight times onto the diabetogenic NONcNZO10/Ltj background. As in humans with T2DM, DT mice lacked an incretin response, although GLP-1 release was maintained. With high-fat (HF) feeding, DT mice remained lean but developed T2DM, whereas wild-type mice developed obesity but not diabetes. Metabolomics identified biochemicals reflecting impaired glucose handling, insulin resistance, and diabetes complications in prediabetic DT/HF mice. β-Hydroxypyruvate and benzoate levels were increased and decreased, respectively, suggesting β-hydroxypyruvate production from d-serine. In vitro, β-hydroxypyruvate altered excitatory properties of myenteric neurons and reduced islet insulin content but not GSIS. β-Hydroxypyruvate-to-d-serine ratios were lower in humans with impaired glucose tolerance compared with normal glucose tolerance and T2DM. Earlier human studies unmasked a neural relay that amplifies GIP-mediated insulin secretion in a pattern reciprocal to β-hydroxypyruvate-to-d-serine ratios in all groups. Thus, K cells may maintain long-term function of neurons and β-cells by regulating β-hydroxypyruvate levels.
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Affiliation(s)
- Sheng Zhang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO
| | - Songyan Wang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO
| | - Matthew D Puhl
- Laboratory for Psychiatric and Molecular Neuroscience, Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, MA
| | - Xuntian Jiang
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO Diabetic Cardiovascular Disease Center, Washington University School of Medicine, St. Louis, MO
| | - Krzysztof L Hyrc
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO
| | - Erin Laciny
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO
| | - Michael J Wallendorf
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO
| | | | - Joseph T Coyle
- Laboratory for Psychiatric and Molecular Neuroscience, Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, MA
| | - Burton M Wice
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO
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23
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Tortorella A, Brambilla F, Fabrazzo M, Volpe U, Monteleone AM, Mastromo D, Monteleone P. Central and peripheral peptides regulating eating behaviour and energy homeostasis in anorexia nervosa and bulimia nervosa: a literature review. EUROPEAN EATING DISORDERS REVIEW 2014; 22:307-20. [PMID: 24942507 DOI: 10.1002/erv.2303] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 05/14/2014] [Accepted: 05/15/2014] [Indexed: 02/03/2023]
Abstract
A large body of literature suggests the occurrence of a dysregulation in both central and peripheral modulators of appetite in patients with anorexia nervosa (AN) and bulimia nervosa (BN), but at the moment, the state or trait-dependent nature of those changes is far from being clear. It has been proposed, although not definitively proved, that peptide alterations, even when secondary to malnutrition and/or to aberrant eating behaviours, might contribute to the genesis and the maintenance of some symptomatic aspects of AN and BN, thus affecting the course and the prognosis of these disorders. This review focuses on the most significant literature studies that explored the physiology of those central and peripheral peptides, which have prominent effects on eating behaviour, body weight and energy homeostasis in patients with AN and BN. The relevance of peptide dysfunctions for the pathophysiology of eating disorders is critically discussed.
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24
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Elucidating the role of neurotensin in the pathophysiology and management of major mental disorders. Behav Sci (Basel) 2014; 4:125-153. [PMID: 25379273 PMCID: PMC4219245 DOI: 10.3390/bs4020125] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/15/2014] [Accepted: 05/21/2014] [Indexed: 12/30/2022] Open
Abstract
Neurotensin (NT) is a neuropeptide that is closely associated with, and is thought to modulate, dopaminergic and other neurotransmitter systems involved in the pathophysiology of various mental disorders. This review outlines data implicating NT in the pathophysiology and management of major mental disorders such as schizophrenia, drug addiction, and autism. The data suggest that NT receptor analogs have the potential to be used as novel therapeutic agents acting through modulation of neurotransmitter systems dys-regulated in these disorders.
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Melander O, Belting M, Manjer J, Maisel AS, Hedblad B, Engström G, Nilsson P, Struck J, Hartmann O, Bergmann A, Orho-Melander M. Validation of plasma proneurotensin as a novel biomarker for the prediction of incident breast cancer. Cancer Epidemiol Biomarkers Prev 2014; 23:1672-6. [PMID: 24925674 DOI: 10.1158/1055-9965.epi-13-1200] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND High fasting plasma proneurotensin concentration was associated with the development of breast cancer in the Malmö Diet and Cancer Study (MDCS). Here, we aimed at replicating the initial finding in an independent second cohort. METHODS The Malmö Preventive Project (MPP) is a population study and comprised 18,240 subjects when examined in 2002-2006. Of women without history of breast cancer at examination, we included all who developed breast cancer during follow-up (n = 130) until December 31, 2010, and a random sample of women without breast cancer until the end of follow-up (n = 1,439) for baseline plasma proneurotensin assessment (mean age, 70.0 ± 4.4 years). Proneurotensin was measured in fasting plasma samples and was related to the risk of later breast cancer development using multivariate logistic regression. RESULTS Proneurotensin [odds ratio (OR) per standard deviation (SD) increment of LN-transformed proneurotensin] was significantly related to incident breast cancer [OR, 2.09; 95% confidence interval (CI), 1.79-2.44; P < 0.001; adjusted for age, body mass index (BMI), smoking, and hormone replacement therapy]. The effect estimate in the MPP was larger than in the discovery cohort (MDCS), with the main difference between the two cohorts being that women of the MPP study were on the average about 10 years older and follow-up time was shorter than that of the MDCS. CONCLUSION As initially found in the MDCS, fasting plasma proneurotensin was significantly associated with the development of breast cancer in the MPP study as well. IMPACT Measurement of plasma proneurotensin warrants further investigation as a blood-based marker for early breast cancer detection.
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Affiliation(s)
- Olle Melander
- Department of Clinical Sciences, Lund University, Malmö; Center of Emergency Medicine, Departments of
| | - Mattias Belting
- Section of Oncology, Lund University, Lund; Oncology, Skane University Hospital, Lund and Malmö, Sweden
| | - Jonas Manjer
- Department of Clinical Sciences, Lund University, Malmö; Surgery and
| | - Alan S Maisel
- Veterans Affairs San Diego Healthcare Systems, San Diego, California
| | - Bo Hedblad
- Department of Clinical Sciences, Lund University, Malmö; Center of Emergency Medicine, Departments of
| | | | - Peter Nilsson
- Department of Clinical Sciences, Lund University, Malmö; Center of Emergency Medicine, Departments of
| | | | | | - Andreas Bergmann
- Sphingotec GmbH, Hennigsdorf; and Waltraut Bergmann Foundation, Hohen Neuendorf, Germany
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Impaired suppression of feeding by the gut hormone xenin in type I interleukin-1 receptor-deficient mice. Behav Brain Res 2014; 261:60-4. [DOI: 10.1016/j.bbr.2013.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/10/2013] [Accepted: 12/02/2013] [Indexed: 11/19/2022]
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Chowdhury S, Reeds DN, Crimmins DL, Patterson BW, Laciny E, Wang S, Tran HD, Griest TA, Rometo DA, Dunai J, Wallendorf MJ, Ladenson JH, Polonsky KS, Wice BM. Xenin-25 delays gastric emptying and reduces postprandial glucose levels in humans with and without type 2 diabetes. Am J Physiol Gastrointest Liver Physiol 2014; 306:G301-9. [PMID: 24356886 PMCID: PMC3920124 DOI: 10.1152/ajpgi.00383.2013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Xenin-25 (Xen) is a neurotensin-related peptide secreted by a subset of glucose-dependent insulinotropic polypeptide (GIP)-producing enteroendocrine cells. In animals, Xen regulates gastrointestinal function and glucose homeostasis, typically by initiating neural relays. However, little is known about Xen action in humans. This study determines whether exogenously administered Xen modulates gastric emptying and/or insulin secretion rates (ISRs) following meal ingestion. Fasted subjects with normal (NGT) or impaired (IGT) glucose tolerance and Type 2 diabetes mellitus (T2DM; n = 10-14 per group) ingested a liquid mixed meal plus acetaminophen (ACM; to assess gastric emptying) at time zero. On separate occasions, a primed-constant intravenous infusion of vehicle or Xen at 4 (Lo-Xen) or 12 (Hi-Xen) pmol · kg(-1) · min(-1) was administered from zero until 300 min. Some subjects with NGT received 30- and 90-min Hi-Xen infusions. Plasma ACM, glucose, insulin, C-peptide, glucagon, Xen, GIP, and glucagon-like peptide-1 (GLP-1) levels were measured and ISRs calculated. Areas under the curves were compared for treatment effects. Infusion with Hi-Xen, but not Lo-Xen, similarly delayed gastric emptying and reduced postprandial glucose levels in all groups. Infusions for 90 or 300 min, but not 30 min, were equally effective. Hi-Xen reduced plasma GLP-1, but not GIP, levels without altering the insulin secretory response to glucose. Intense staining for Xen receptors was detected on PGP9.5-positive nerve fibers in the longitudinal muscle of the human stomach. Thus Xen reduces gastric emptying in humans with and without T2DM, probably via a neural relay. Moreover, endogenous GLP-1 may not be a major enhancer of insulin secretion in healthy humans under physiological conditions.
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Affiliation(s)
- Sara Chowdhury
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Dominic N. Reeds
- 2Division of Nutritional Science, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Dan L. Crimmins
- 3Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri;
| | - Bruce W. Patterson
- 2Division of Nutritional Science, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Erin Laciny
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Songyan Wang
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Hung D. Tran
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Terry A. Griest
- 3Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri;
| | - David A. Rometo
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Judit Dunai
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
| | - Michael J. Wallendorf
- 4Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri; and
| | - Jack H. Ladenson
- 3Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri;
| | - Kenneth S. Polonsky
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri; ,5Division of the Biological Sciences and Pritzker School of Medicine, The University of Chicago, Chicago, Illinois
| | - Burton M. Wice
- 1Division of Endocrinology, Metabolism and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri;
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Tetens J, Thaller G, Krattenmacher N. Genetic and genomic dissection of dry matter intake at different lactation stages in primiparous Holstein cows. J Dairy Sci 2014; 97:520-31. [DOI: 10.3168/jds.2013-7301] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 09/23/2013] [Indexed: 11/19/2022]
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Chowdhury S, Wang S, Patterson BW, Reeds DN, Wice BM. The combination of GIP plus xenin-25 indirectly increases pancreatic polypeptide release in humans with and without type 2 diabetes mellitus. ACTA ACUST UNITED AC 2013; 187:42-50. [PMID: 24183983 DOI: 10.1016/j.regpep.2013.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/07/2013] [Accepted: 10/23/2013] [Indexed: 12/25/2022]
Abstract
Xenin-25 (Xen) is a 25-amino acid neurotensin-related peptide that activates neurotensin receptor-1 (NTSR1). We previously showed that Xen increases the effect of glucose-dependent insulinotropic polypeptide (GIP) on insulin release 1) in hyperglycemic mice via a cholinergic relay in the periphery independent from the central nervous system and 2) in humans with normal or impaired glucose tolerance, but not type 2 diabetes mellitus (T2DM). Since this blunted response to Xen defines a novel defect in T2DM, it is important to understand how Xen regulates islet physiology. On separate visits, subjects received intravenous graded glucose infusions with vehicle, GIP, Xen, or GIP plus Xen. The pancreatic polypeptide response was used as an indirect measure of cholinergic input to islets. The graded glucose infusion itself had little effect on the pancreatic polypeptide response whereas administration of Xen equally increased the pancreatic polypeptide response in humans with normal glucose tolerance, impaired glucose tolerance, and T2DM. The pancreatic polypeptide response to Xen was similarly amplified by GIP in all 3 groups. Antibody staining of human pancreas showed that NTSR1 is not detectable on islet endocrine cells, sympathetic neurons, blood vessels, or endothelial cells but is expressed at high levels on PGP9.5-positive axons in the exocrine tissue and at low levels on ductal epithelial cells. PGP9.5 positive nerve fibers contacting beta cells in the islet periphery were also observed. Thus, a neural relay, potentially involving muscarinic acetylcholine receptors, indirectly increases the effects of Xen on pancreatic polypeptide release in humans.
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Affiliation(s)
- Sara Chowdhury
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, MO, United States
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Opland D, Sutton A, Woodworth H, Brown J, Bugescu R, Garcia A, Christensen L, Rhodes C, Myers M, Leinninger G. Loss of neurotensin receptor-1 disrupts the control of the mesolimbic dopamine system by leptin and promotes hedonic feeding and obesity. Mol Metab 2013; 2:423-34. [PMID: 24327958 DOI: 10.1016/j.molmet.2013.07.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 07/24/2013] [Accepted: 07/25/2013] [Indexed: 01/04/2023] Open
Abstract
Neurons of the lateral hypothalamic area (LHA) control motivated behaviors such as feeding and ambulatory activity, in part by modulating mesolimbic dopamine (DA) circuits. The hormone, leptin, acts via the long form of the leptin receptor (LepRb) in the brain to signal the repletion of body energy stores, thereby decreasing feeding and promoting activity. LHA LepRb neurons, most of which contain neurotensin (Nts; LepRb(Nts) neurons) link leptin action to the control of mesolimbic DA function and energy balance. To understand potential roles for Nts in these processes, we examined mice null for Nts receptor 1 (NtsR1KO). While NtsR1KO mice consume less food than controls on a chow diet, they eat more and become obese when fed a high-fat, high-sucrose palatable diet; NtsR1KO mice also exhibit augmented sucrose preference, consistent with increased hedonic feeding in these animals. We thus sought to understand potential roles for NtsR1 in the control of the mesolimbic DA system and LHA leptin action. LHA Nts cells project to DA-containing midbrain areas, including the ventral tegmental area (VTA) and the substantia nigra (SN), where many DA neurons express NtsR1. Furthermore, in contrast to wild-type mice, intra-LHA leptin treatment increased feeding and decreased VTA Th expression in NtsR1KO mice, consistent with a role for NtsR1 signaling from LHA LepRb neurons in the suppression of food intake and control of mesolimbic DA function. Additionally, these data suggest that other leptin-regulated LHA neurotransmitters normally oppose aspects of Nts action to promote balanced responses to leptin.
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Key Words
- DA, dopamine
- Dopamine
- LHA, lateral hypothalamic area
- LepRb, long form of the leptin receptor
- MCH, melanin concentrating hormone
- NAc, nucleus accumbens
- Neurotensin
- Nts, neurotensin
- NtsR1, neurotensin receptor-1
- NtsR1KO, neurotensin receptor-1 knock out
- NtsR2, neurotensin receptor-2
- OX, Orexin/hypocretin
- Obesity
- Orexin
- PD, palatable diet
- SN, substantia nigra
- TH, tyrosine hydroxylase
- VTA, ventral tegmental area
- pSTAT3, phosphorylation of signal transducer and activator of transcription 3
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Affiliation(s)
- Darren Opland
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
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Boules M, Li Z, Smith K, Fredrickson P, Richelson E. Diverse roles of neurotensin agonists in the central nervous system. Front Endocrinol (Lausanne) 2013; 4:36. [PMID: 23526754 PMCID: PMC3605594 DOI: 10.3389/fendo.2013.00036] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 03/06/2013] [Indexed: 01/10/2023] Open
Abstract
Neurotensin (NT) is a tridecapeptide that is found in the central nervous system (CNS) and the gastrointestinal tract. NT behaves as a neurotransmitter in the brain and as a hormone in the gut. Additionally, NT acts as a neuromodulator to several neurotransmitter systems including dopaminergic, sertonergic, GABAergic, glutamatergic, and cholinergic systems. Due to its association with such a wide variety of neurotransmitters, NT has been implicated in the pathophysiology of several CNS disorders such as schizophrenia, drug abuse, Parkinson's disease (PD), pain, central control of blood pressure, eating disorders, as well as, cancer and inflammation. The present review will focus on the role that NT and its analogs play in schizophrenia, endocrine function, pain, psychostimulant abuse, and PD.
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Affiliation(s)
- Mona Boules
- Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic FloridaJacksonville, FL, USA
- *Correspondence: Mona Boules, Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA. e-mail:
| | - Zhimin Li
- Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic FloridaJacksonville, FL, USA
| | - Kristin Smith
- Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic FloridaJacksonville, FL, USA
| | - Paul Fredrickson
- Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic FloridaJacksonville, FL, USA
| | - Elliott Richelson
- Neuropsychopharmacology Laboratory, Department of Neuroscience, Mayo Clinic FloridaJacksonville, FL, USA
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Zhang S, Hyrc K, Wang S, Wice BM. Xenin-25 increases cytosolic free calcium levels and acetylcholine release from a subset of myenteric neurons. Am J Physiol Gastrointest Liver Physiol 2012; 303:G1347-55. [PMID: 23086920 PMCID: PMC3532549 DOI: 10.1152/ajpgi.00116.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Xenin-25 (Xen) is a 25 amino acid neurotensin-related peptide reportedly produced with glucose-dependent insulinotropic polypeptide (GIP) by a subset of K cells in the proximal gut. We previously showed exogenously administered Xen, with GIP but not alone, increases insulin secretion in humans and mice. In mice, this effect is indirectly mediated via a central nervous system-independent cholinergic relay in the periphery. Xen also delays gastric emptying, reduces food intake, induces gall bladder contractions, and increases gut motility and secretion from the exocrine pancreas, suggesting that some effects of Xen could be mediated by myenteric neurons (MENs). To determine whether Xen activates these neurons, MENs were isolated from guinea pig proximal small intestines. Cells expressed neuronal markers and exhibited typical neuron-like morphology with extensive outgrowths emanating from cell bodies. Cytosolic free Ca(2+) levels ([Ca(2+)](i)) were measured using Fura-2. ATP/UTP, KCl, and forskolin increased [Ca(2+)](i) in 99.6%, 92%, and 23% of the MENs imaged, respectively, indicating that they are functional and activated by nucleotide receptor signaling, direct depolarization, and cAMP. [Ca(2+)](i) increased in only 12.7% of MENs treated with Xen. This rise was blocked by pretreatment with EGTA, diazoxide, SR48692, and neurotensin. Thus the Xen-mediated increase in [Ca(2+)](i) involves influx of extracellular Ca(2+) and activation of neurotensin receptor-1 (NTSR1). Xen also increased acetylcholine release from MENs. Amylin, produced by β-and enteroendocrine cells, delays gastric emptying and increased [Ca(2+)](i) almost exclusively in Xen-responsive MENs. Immunohistochemistry demonstrated NTSR1 expression in human duodenal MENs. Thus myenteric rather than central neurons could mediate some effects of Xen and amylin.
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Affiliation(s)
- Sheng Zhang
- Department of Internal Medicine, Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, Saint Louis, Missouri 63110, USA
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Wice BM, Reeds DN, Tran HD, Crimmins DL, Patterson BW, Dunai J, Wallendorf MJ, Ladenson JH, Villareal DT, Polonsky KS. Xenin-25 amplifies GIP-mediated insulin secretion in humans with normal and impaired glucose tolerance but not type 2 diabetes. Diabetes 2012; 61:1793-800. [PMID: 22522617 PMCID: PMC3379667 DOI: 10.2337/db11-1451] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) potentiates glucose-stimulated insulin secretion (GSIS). This response is blunted in type 2 diabetes (T2DM). Xenin-25 is a 25-amino acid neurotensin-related peptide that amplifies GIP-mediated GSIS in hyperglycemic mice. This study determines if xenin-25 amplifies GIP-mediated GSIS in humans with normal glucose tolerance (NGT), impaired glucose tolerance (IGT), or T2DM. Each fasting subject received graded glucose infusions to progressively raise plasma glucose concentrations, along with vehicle alone, GIP, xenin-25, or GIP plus xenin-25. Plasma glucose, insulin, C-peptide, and glucagon levels and insulin secretion rates (ISRs) were determined. GIP amplified GSIS in all groups. Initially, this response was rapid, profound, transient, and essentially glucose independent. Thereafter, ISRs increased as a function of plasma glucose. Although magnitudes of insulin secretory responses to GIP were similar in all groups, ISRs were not restored to normal in subjects with IGT and T2DM. Xenin-25 alone had no effect on ISRs or plasma glucagon levels, but the combination of GIP plus xenin-25 transiently increased ISR and plasma glucagon levels in subjects with NGT and IGT but not T2DM. Since xenin-25 signaling to islets is mediated by a cholinergic relay, impaired islet responses in T2DM may reflect defective neuronal, rather than GIP, signaling.
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Affiliation(s)
- Burton M. Wice
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
- Corresponding author: Kenneth S. Polonsky, , or Burton M. Wice,
| | - Dominic N. Reeds
- Division of Nutritional Science, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Hung D. Tran
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Dan L. Crimmins
- Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Bruce W. Patterson
- Division of Nutritional Science, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Judit Dunai
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Michael J. Wallendorf
- Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri
| | - Jack H. Ladenson
- Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Dennis T. Villareal
- Division of Geriatrics, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
- Department of Geriatrics, University of New Mexico School of Medicine and New Mexico Veterans Affairs Health Care System, Albuquerque, New Mexico
| | - Kenneth S. Polonsky
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
- Division of Biological Sciences and Pritzker School of Medicine, The University of Chicago, Chicago, Illinois
- Corresponding author: Kenneth S. Polonsky, , or Burton M. Wice,
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Good DJ. Extending the reach of Exendin-4: new pathways in the control of body weight and glucose homeostasis. Endocrinology 2012; 153:2051-3. [PMID: 22523329 PMCID: PMC3339655 DOI: 10.1210/en.2012-1149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 02/29/2012] [Indexed: 12/11/2022]
Affiliation(s)
- Deborah J Good
- Department of Human Nutrition, Foods and Exercise, Virginia Tech, Blacksburg, Virginia 24061, USA.
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Rao SM, Auger JL, Gaillard P, Weissleder R, Wada E, Torres R, Kojima M, Benoist C, Mathis D, Binstadt BA. The neuropeptide neuromedin U promotes autoantibody-mediated arthritis. Arthritis Res Ther 2012; 14:R29. [PMID: 22314006 PMCID: PMC3392824 DOI: 10.1186/ar3732] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/20/2011] [Accepted: 02/07/2012] [Indexed: 12/17/2022] Open
Abstract
Introduction Neuromedin U (NMU) is a neuropeptide with pro-inflammatory activity. The primary goal of this study was to determine if NMU promotes autoantibody-induced arthritis. Additional studies addressed the cellular source of NMU and sought to define the NMU receptor responsible for its pro-inflammatory effects. Methods Serum containing arthritogenic autoantibodies from K/BxN mice was used to induce arthritis in mice genetically lacking NMU. Parallel experiments examined whether NMU deficiency impacted the early mast-cell-dependent vascular leak response induced by these autoantibodies. Bone-marrow chimeric mice were generated to determine whether pro-inflammatory NMU is derived from hematopoietic cells or stromal cells. Mice lacking the known NMU receptors singly and in combination were used to determine susceptibility to serum-transferred arthritis and in vitro cellular responses to NMU. Results NMU-deficient mice developed less severe arthritis than control mice. Vascular leak was not affected by NMU deficiency. NMU expression by bone-marrow-derived cells mediated the pro-arthritogenic effect. Deficiency of all of the known NMU receptors, however, had no impact on arthritis severity and did not affect the ability of NMU to stimulate intracellular calcium flux. Conclusions NMU-deficient mice are protected from developing autoantibody-induced inflammatory arthritis. NMU derived from hematopoietic cells, not neurons, promotes the development of autoantibody-induced inflammatory arthritis. This effect is mediated by a receptor other than the currently known NMU receptors.
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Affiliation(s)
- Sindhuja M Rao
- Center for Immunology and Department of Pediatrics, University of Minnesota, Medical Biosciences Building, 2101 6th St SE Minneapolis, MN, 55414, USA
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Mazella J, Béraud-Dufour S, Devader C, Massa F, Coppola T. Neurotensin and its receptors in the control of glucose homeostasis. Front Endocrinol (Lausanne) 2012; 3:143. [PMID: 23230428 PMCID: PMC3515879 DOI: 10.3389/fendo.2012.00143] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 11/05/2012] [Indexed: 01/05/2023] Open
Abstract
The pharmacological roles of the neuropeptide neurotensin through its three known receptors are various and complex. Neurotensin is involved in several important biological functions including analgesia and hypothermia in the central nervous system and also food intake and glucose homeostasis in the periphery. This review focuses on recent works dealing with molecular mechanisms regulating blood glucose level and insulin secretion upon neurotensin action. Investigations on crucial cellular components involved in the protective effect of the peptide on beta cells are also detailed. The role of xenin, a neurotensin-related peptide, on the regulation of insulin release by glucose-dependent insulinotropic polypeptide is summarized. The last section comments on the future research areas which should be developed to address the function of new effectors of the neurotensinergic system in the endocrine pancreas.
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Affiliation(s)
- Jean Mazella
- *Correspondence: Jean Mazella and Thierry Coppola, Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275, Centre National de la Recherche Scientifique, Université de Nice-Sophia Antipolis, 660 route des Lucioles, Sophia Antipolis, 06560 Valbonne, France. e-mail: ;
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Kalafatakis K, Triantafyllou K. Contribution of neurotensin in the immune and neuroendocrine modulation of normal and abnormal enteric function. ACTA ACUST UNITED AC 2011; 170:7-17. [DOI: 10.1016/j.regpep.2011.04.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 03/22/2011] [Accepted: 04/16/2011] [Indexed: 12/19/2022]
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Mustain WC, Rychahou PG, Evers BM. The role of neurotensin in physiologic and pathologic processes. Curr Opin Endocrinol Diabetes Obes 2011; 18:75-82. [PMID: 21124211 DOI: 10.1097/med.0b013e3283419052] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE OF REVIEW Neurotensin is a 13-amino acid peptide found in the central nervous system central nervous system and the gastrointestinal tract. Since its initial discovery in 1973, neurotensin has been shown to play a role in a wide range of physiologic and pathologic processes throughout the body. Ongoing research efforts continue to clarify the role of neurotensin in various central nervous system and gastrointestinal processes, as well as how disruption of these normal mechanisms may lead to diseases ranging from schizophrenia to colorectal cancer. The goal of this review is to provide an overview of the most recent advances in the field of neurotensin research, in the context of what has been previously published. RECENT FINDINGS Because of the seemingly unrelated functions of neurotensin in the central nervous system and the periphery, the scope of the articles reviewed is rather broad. Contributions continue to be made to our understanding of the downstream effects of neurotensin signaling and the complex feedback loops between neurotensin and other signaling molecules. By selective targeting or blockade of specific neurotensin receptors, investigators have identified potential drugs for use in the treatment of schizophrenia, alcoholism, chronic pain, or cancer. Neurotensin-based pharmacologic agents are being used successfully in animal models for a number of these conditions. SUMMARY The review highlights the wide array of biological processes in which neurotensin has a role, and summarizes the most recent advances in various fields of neurotensin research. The knowledge gained through this research has led to the development of first-in-class drugs for the treatment of various medical conditions, and it is clear that in the coming years some of these agents will be ready to move from the bench to the bedside in clinical trials.
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Affiliation(s)
- W Conan Mustain
- Department of Surgery, University of Kentucky, Lexington, Kentucky, USA
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Current world literature. Curr Opin Endocrinol Diabetes Obes 2011; 18:83-98. [PMID: 21178692 DOI: 10.1097/med.0b013e3283432fa7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Comprehensive copy number variant (CNV) analysis of neuronal pathways genes in psychiatric disorders identifies rare variants within patients. J Psychiatr Res 2010; 44:971-8. [PMID: 20398908 DOI: 10.1016/j.jpsychires.2010.03.007] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 03/12/2010] [Accepted: 03/16/2010] [Indexed: 01/11/2023]
Abstract
BACKGROUND Copy number variations (CNV) have become an important source of human genome variability noteworthy to consider when studying genetic susceptibility to complex diseases. As recent studies have found evidences for the potential involvement of CNVs in psychiatric disorders, we have studied the dosage effect of structural genome variants as a possible susceptibility factor for different psychiatric disorders in a candidate gene approach. METHODS After selection of 68 psychiatric disorders' candidate genes overlapping with CNVs, MLPA assays were designed to determine changes in copy number of these genes. The studied sample consisted of 724 patients with psychiatric disorders (accounting for anxiety disorders, mood disorders, eating disorders and schizophrenia) and 341 control individuals. RESULTS CNVs were detected in 30 out of the 68 genes screened, indicating that a considerable proportion of neuronal pathways genes contain CNVs. When testing the overall burden of rare structural genomic variants in the different psychiatric disorders compared to control individuals, there was no statistically significant difference in the total amount of gains and losses. However, 14 out of the 30 changes were only found in psychiatric disorder patients but not in control individuals. These genes include GRM7, previously associated to major depression disorder and bipolar disorder, SLC6A13, in anxiety disorders, and S100B, SSTR5 and COMT in schizophrenia. CONCLUSIONS Although we have not been able to found a clear association between the studied CNVs and psychiatric disorders, the rare variants found only within the patients could account for a step further towards understanding the pathophysiology of psychiatric disorders.
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Kim ER, Mizuno TM. Xenin delays gastric emptying rate and activates the brainstem in mice. Neurosci Lett 2010; 481:59-63. [PMID: 20599589 DOI: 10.1016/j.neulet.2010.06.055] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Revised: 05/24/2010] [Accepted: 06/21/2010] [Indexed: 11/15/2022]
Abstract
Xenin, a 25-amino acid gastrointestinal peptide, inhibits feeding by acting through the central nervous system. Gastrointestinal hormones reduce food intake partly by activating the brainstem and inhibiting gastric emptying. Therefore, we hypothesized that xenin delays gastric emptying through the activation of the brainstem cells. To address this hypothesis, we examined the effect of intraperitoneal (i.p.) injection of xenin on gastric emptying rate and brainstem Fos expression in mice. Gastric emptying rate was reduced by about 93% in xenin-treated mice compared to saline-treated control mice. The i.p. xenin injection significantly increased Fos-immunoreactive cells in the nucleus of the solitary tract (NTS) of the brainstem, but not area postrema (AP) and dorsal motor nucleus of the vagus (DMV). These findings support the hypothesis that xenin-induced anorexia is at least partly due to delayed gastric emptying and the activation of the NTS cells.
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Affiliation(s)
- Eun Ran Kim
- Department of Physiology, University of Manitoba, Winnipeg, MB R3E0J9, Canada
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