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Smith KR, Moran TH. Gastrointestinal peptides in eating-related disorders. Physiol Behav 2021; 238:113456. [PMID: 33989649 DOI: 10.1016/j.physbeh.2021.113456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 04/19/2021] [Accepted: 05/04/2021] [Indexed: 12/13/2022]
Abstract
Food intake is tightly controlled by homeostatic signals sensitive to metabolic need for the regulation of body weight. This review focuses on the peripherally-secreted gastrointestinal peptides (i.e., ghrelin, cholecystokinin, glucagon-like peptide 1, and peptide tyrosine tyrosine) that contribute to the control of appetite and discusses how these peptides or the signals arising from their release are disrupted in eating-related disorders across the weight spectrum, namely anorexia nervosa, bulimia nervosa, and obesity, and whether they are normalized following weight restoration or weight loss treatment. Further, the role of gut peptides in the pathogenesis and treatment response in human weight conditions as identified by rodent models are discussed. Lastly, we review the incretin- and hormone-based pharmacotherapies available for the treatment of obesity and eating-related disorders.
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Affiliation(s)
- Kimberly R Smith
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States.
| | - Timothy H Moran
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, United States
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2
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Mhalhal TR, Washington MC, Heath JC, Sayegh AI. Effect of Vagotomy and Sympathectomy on the Feeding Responses Evoked by Intra-Aortic Cholecystokinin-8 in Adult Male Sprague Dawley Rats. Endocr Res 2021; 46:57-65. [PMID: 33426974 DOI: 10.1080/07435800.2020.1861621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The vagus nerve and the celiaco-mesenteric ganglia (CMG) are required for reduction of meal size (MS) and prolongation of the intermeal interval (IMI) by intraperitoneal (ip) sulfated cholecystokinin-8 (CCK-8). However, recently we have shown that the gut regulates these responses. Therefore, reevaluating the role of the vagus and the CMG in the feeding responses evoked by CCK is necessary because the gut contains the highest concentration of enteric, vagal and splanchnic afferents and CCK-A receptors, which are required for reduction of food intake by this peptide, compared to other abdominal organs. To address this necessity, we injected sulfated CCK-8 (0, 0.1, 0.5, 1 and 3 nmol/kg) in the aorta, near the gastrointestinal sites of action of the peptide, in three groups of free-feeding rats (n = 10 rats per group), subdiaphragmatic vagotomy (VGX), celiaco-mesenteric ganglionectomy (CMGX) and sham-operated, and recorded seven feeding responses. In the sham group, CCK-8 reduced MS (normal chow), prolonged the intermeal interval (IMI, time between first and second meals), increased satiety ratio (SR, IMI/MS), shortened duration of first meal, reduced total (24 hrs) food intake and reduced number of meals relative to saline vehicle. Vagotomy attenuated all of the previous responses except IMI length and SR, and CMGX attenuated all of those responses. In conclusion, the feeding responses evoked by sulfated CCK-8 require, independently, the vagus nerve and the CMG.
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Affiliation(s)
- Thaer R Mhalhal
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, 36088, USA
- Department of Anatomy and Histology, College of Veterinary Medicine, University of Basrah, Basrah, Iraq
| | - Martha C Washington
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, 36088, USA
| | - John C Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, 36088, USA
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, 36088, USA
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Wang C, Zhang C, Wu D, Guo L, Zhao F, Lv J, Fu L. Cholecystokinin octapeptide reduces myocardial fibrosis and improves cardiac remodeling in post myocardial infarction rats. Int J Biochem Cell Biol 2020; 125:105793. [PMID: 32554056 DOI: 10.1016/j.biocel.2020.105793] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 06/03/2020] [Accepted: 06/13/2020] [Indexed: 12/09/2022]
Abstract
BACKGROUND/AIMS Myocardial infarction (MI) increases myocardial fibrosis (MF) and subsequent cardiac remodeling. Cholecystokinin octapeptide (CCK-8) is expressed in cardiomyocytes and plays an important role in cardiovascular regulation. In this study, we intend to use a rat model of myocardial infarction to evaluate the effects of CCK-8 on myocardial fibrosis and cardiac remodeling. METHODS Male Sprague-Dawley rats were separated into 3 groups: sham operation, MI + NaCl, and MI + CCK-8. All rats were subjected to left coronary artery ligation to induce MI or sham operation and then treated with CCK-8 or saline for 28 days. After 4 weeks, echocardiography was performed to assess cardiac function and myocardial fibrosis was evaluated using H&E and Masson's Trichrome-stained sections. The levels of BNP, CCK-8 in the plasma of all rats were detected by ELISA; RNA sequencing (RNA-seq) analysis was also adapted to detect differentially expressed genes in myocardial tissues of each group. Myocardial expression of fibrosis markers was analyzed by western blotting, immunohistochemistry and qRT-PCR. RESULTS CCK-8 was demonstrated to improve left ventricular function and results of H&E staining, Masson's trichrome staining, immunohistochemistry and western blotting showed that CCK-8 attenuated MF. Gene expression profiles of the left ventricles were analysed by RNA-seq and validated by qRT-PCR. Cardiac fibrosis genes were downregulated by CCK-8 in the left ventricle. SIGNIFICANCE CCK-8 can alleviate fibrosis in the noninfarcted regions and delay the left ventricular remodeling and the progress of heart failure in a MI rat model.
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Affiliation(s)
- Can Wang
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Cuili Zhang
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Dongdong Wu
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Lu Guo
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Fali Zhao
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jinxin Lv
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Lu Fu
- Laboratory of Cardiovascular Internal Medicine Department, The First Affiliated Hospital of Harbin Medical University, Harbin, China.
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Dafalla AI, Mhalhal TR, Hiscocks K, Heath J, Sayegh AI. The Vagus Nerve and the Celiaco-mesenteric Ganglia Participate in the Feeding Responses Evoked by Non-sulfated Cholecystokinin-8 in Male Sprague Dawley Rats. Endocr Res 2020; 45:73-83. [PMID: 31573821 DOI: 10.1080/07435800.2019.1670673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We have shown that non-sulfated cholecystokinin-8 (NS CCK-8) reduces food intake in adult male Sprague Dawley rats by activating cholecystokinin-B receptor (CCK-BR). Here, we tested the hypothesis that the vagus nerve and the celiaco-mesenteric ganglia may play a role in this reduction. The hypothesis stems from the following facts. The vagus and the celiaco-mesenteric ganglia contain NS CCK-8, they express and have binding sites for CCK-BR, NS CCK-8 activates CCK-BR on afferent vagal and sympathetic fibers and the two structures link the gastrointestinal tract to central feeding nuclei in the brain, which also contain the peptide and CCK-BR. To test this hypothesis, three groups of free-feeding rats, vagotomy (VGX), celiaco-mesenteric ganglionectomy (CMGX) and sham-operated, received NS CCK-8 (0, 0.5 and 1 nmol/kg) intraperitoneally prior to the onset of the dark cycle and various feeding behaviors were recorded. We found that in sham-operated rats both doses of NS CCK-8 reduced meal size (MS), prolonged the intermeal interval (IMI, time between first and second meal), increased satiety ratio (SR = IMI/MS), reduced 24-h food intake and reduced the number of meals relative to saline control. In the VGX and the CMGX groups, all of the previous responses were attenuated. Consistent with our hypothesis, the findings of the current work suggest a role for the vagus nerve and the celiaco-mesenteric ganglia in the feeding responses evoked by NS CCK-8.
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Affiliation(s)
- Amged I Dafalla
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - Thaer R Mhalhal
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
- Department of Anatomy and Histology, College of Veterinary Medicine, Basra University, Basra, Iraq
| | - Kenneth Hiscocks
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - John Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL, USA
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Dafalla AI, Mhalhal TR, Hiscocks K, Heath J, Sayegh AI. Non-sulfated cholecystokinin-8 increases enteric and hindbrain Fos-like immunoreactivity in male Sprague Dawley rats. Brain Res 2018; 1708:200-206. [PMID: 30571983 DOI: 10.1016/j.brainres.2018.12.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 12/13/2022]
Abstract
Recently, we reported that non-sulfated cholecystokinin-8 (NS CCK-8) reduces food intake by cholecystokinin-B receptors (CCK-BR). To examine a possible site of action for this peptide, and based on the fact that both NS CCK-8 and CCK-BR are found centrally and peripherally, in the current study we hypothesized that NS CCK-8 increases Fos-like immunoreactivity (Fos-LI, a neuronal activation marker) in the dorsal vagal complex (DVC) of the hindbrain and the myenteric and submucosal plexuses of the small intestine. We found that intraperitoneal NS CCK-8 (0.5 nmol/kg) increases Fos-LI in the DVC, the myenteric and the submucosal plexuses of the duodenum and the myenteric plexus of the jejunum. The findings suggest, but does not prove, a potential role for the DVC and the enteric neurons in the feeding responses evoked by NS CCK-8.
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Affiliation(s)
- Amged I Dafalla
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee AL36088, United States
| | - Thaer R Mhalhal
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee AL36088, United States
| | - Kenneth Hiscocks
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee AL36088, United States
| | - John Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee AL36088, United States
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee AL36088, United States.
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Mhalhal TR, Washington MC, Newman KD, Heath JC, Sayegh AI. Combined gastrin releasing peptide-29 and glucagon like peptide-1 reduce body weight more than each individual peptide in diet-induced obese male rats. Neuropeptides 2018; 67:71-78. [PMID: 29180139 DOI: 10.1016/j.npep.2017.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 11/10/2017] [Accepted: 11/17/2017] [Indexed: 12/14/2022]
Abstract
To test the hypothesis that gastrin releasing peptide-29 (GRP-29) combined with glucagon like peptide-1 (7-36) (GLP-1 (7-36)) reduce body weight (BW) more than each of the peptides given individually, we infused the two peptides (0.5nmol/kg each) in the aorta of free feeding, diet-induced obese (DIO) male Sprague Dawley rats once daily for 25days and measured BW. We found that GRP-29 and GLP-1 reduce BW, GRP-29 reduced it more than GLP-1 and GRP-29+GLP-1 reduce BW more than each peptide given alone. This reduction was accompanied by decrease 24-hour food intake (normal rat chow), meal size (MS), duration of first meal and number of meals, and increase latency to the first meal, intermeal interval (IMI) and satiety ratio (IMI/MS, amount of food consumed per a unit of time). Furthermore, the peptides and their combination decreased 24-hour glucose levels. In conclusion, GRP-29+GLP-1 reduce BW more than each of the peptides given individually.
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Affiliation(s)
- Thaer R Mhalhal
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA; Department of Anatomy and Histology, College of Veterinary Medicine, University of Basrah, Basrah, Iraq
| | - Martha C Washington
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA
| | - Kayla D Newman
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA
| | - John C Heath
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA
| | - Ayman I Sayegh
- Gastroenterology Laboratory, Department of Biomedical Sciences, College of Veterinary Medicine, Tuskegee University, Tuskegee, AL 36088, USA.
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Medeiros AFD, Costa IDS, Carvalho FMCD, Kiyota S, Souza BBPD, Sifuentes DN, Serquiz RP, Maciel BLL, Uchôa AF, Santos EAD, Morais AHDA. Biochemical characterisation of a Kunitz-type inhibitor from Tamarindus indica L. seeds and its efficacy in reducing plasma leptin in an experimental model of obesity. J Enzyme Inhib Med Chem 2018; 33:334-348. [PMID: 29322840 PMCID: PMC6010142 DOI: 10.1080/14756366.2017.1419220] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A trypsin inhibitor isolated from tamarind seed (TTI) has satietogenic effects in animals, increasing the cholecystokinin (CCK) in eutrophy and reducing leptin in obesity. We purified TTI (pTTI), characterised, and observed its effect upon CCK and leptin in obese Wistar rats. By HPLC, and after amplification of resolution, two protein fractions were observed: Fr1 and Fr2, with average mass of [M + 14H]+ = 19,594,690 Da and [M + 13H]+ = 19,578,266 Da, respectively. The protein fractions showed 54 and 53 amino acid residues with the same sequence. pTTI presented resistance to temperature and pH variations; IC50 was 2.7 × 10−10 mol.L−1 and Ki was 2.9 × 10−11 mol.L−1. The 2-DE revealed spots with isoelectric points between pH 5 and 6, and one near pH 8. pTTI action on leptin decrease was confirmed. We conclude that pTTI is a Kunitz trypsin inhibitor with possible biotechnological health-related application.
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Affiliation(s)
- Amanda Fernandes de Medeiros
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil
| | - Izael de Sousa Costa
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil
| | | | - Sumika Kiyota
- b Laboratory of Protein and Peptide Biochemistry , CPDSA, Biological Institute , São Paulo , Brazil
| | - Beatriz Blenda Pinheiro de Souza
- c Postgraduate Biological Molecular, Institute of Biological Sciences , University of Brasília , Distrito Federal , Brasília , Brazil.,d Embrapa Genetic Resources and Biotechnology , Embrapa , Distrito Federal , Brasília , Brazil
| | | | - Raphael Paschoal Serquiz
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil
| | - Bruna Leal Lima Maciel
- e Postgraduate Nutrition Program, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil.,f Department of Nutrition, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil
| | - Adriana Ferreira Uchôa
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.,g Department of Cell Biology and Genetics, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil
| | - Elizeu Antunes Dos Santos
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.,h Department of Biochemistry, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil
| | - Ana Heloneida de Araújo Morais
- a Postgraduate Biochemistry Program, Biosciences Center , Federal University of Rio Grande do Norte , Natal , Brazil.,e Postgraduate Nutrition Program, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil.,f Department of Nutrition, Center for Health Sciences , Federal University of Rio Grande do Norte , Natal , Brazil
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Costa IS, Medeiros AF, Carvalho FMC, Lima VCO, Serquiz RP, Serquiz AC, Silbiger VN, Bortolin RH, Maciel BLL, Santos EA, Morais AHA. Satietogenic Protein from Tamarind Seeds Decreases Food Intake, Leptin Plasma and CCK-1r Gene Expression in Obese Wistar Rats. Obes Facts 2018; 11:440-453. [PMID: 30537704 PMCID: PMC6341364 DOI: 10.1159/000492733] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 08/07/2018] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE This study evaluated the effect of a protein, the isolated Trypsin Inhibitor (TTI) from Tamarindus indica L. seed, as a CCK secretagogue and its action upon food intake and leptin in obese Wistar rats. METHODS Three groups of obese rats were fed 10 days one of the following diets: Standard diet (Labina®) + water; High Glycemic Index and Load (HGLI) diet + water or HGLI diet + TTI. Lean animals were fed the standard diet for the 10 days. Food intake, zoometric measurements, plasma CCK, plasma leptin, relative mRNA expression of intestinal CCK-related genes, and expression of the ob gene in subcutaneous adipose tissue were assessed. RESULTS TTI decreased food intake but did not increase plasma CCK in obese animals. On the other hand, TTI treatment decreased CCK-1R gene expression in obese animals compared with the obese group with no treatment (p = 0.027). Obese animals treated with TTI presented lower plasma leptin than the non-treated obese animals. CONCLUSION We suggest that TTI by decreasing plasma leptin may improve CCK action, regardless of its increase in plasma from obese rats, since food intake was lowest.
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Affiliation(s)
- Izael S Costa
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Amanda F Medeiros
- Biochemistry Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Fabiana M C Carvalho
- Biochemistry Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Vanessa C O Lima
- Biochemistry Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Raphael P Serquiz
- Biochemistry Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil
| | | | - Vivian N Silbiger
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
- Department of Clinical and Toxicological Analysis, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Raul H Bortolin
- Department of Clinical and Toxicological Analysis, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Bruna L L Maciel
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Elizeu A Santos
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Ana H A Morais
- Nutrition Postgraduate Program, Center for Health Sciences, Federal University of Rio Grande do Norte, Natal, Brazil,
- Biochemistry Postgraduate Program, Biosciences Center, Federal University of Rio Grande do Norte, Natal, Brazil,
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Peptide Tyrosine Tyrosine 3-36 Reduces Meal Size and Activates the Enteric Neurons in Male Sprague-Dawley Rats. Dig Dis Sci 2017; 62:3350-3358. [PMID: 29030744 DOI: 10.1007/s10620-017-4788-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 10/04/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND Peptide tyrosine tyrosine 3-36 (peptide YY 3-36 or PYY 3-36) reduces food intake by unknown site(s). AIM To test the hypothesis that the gastrointestinal tract contains sites of action regulating meal size (MS) and intermeal interval (IMI) length by PYY 3-36. METHODS Peptide YY 3-36 (0, 1, 5, 10 and 20 nmol/kg) was injected in the aorta, the artery that supplies the gastrointestinal tract, prior to the onset of the dark cycle in free feeding male Sprague-Dawley rats and food intake was measured. Then, PYY 3-36 (25 nmol/kg) was injected intraperitoneally in these rats and Fos-like immunoreactivity (Fos-LI, a marker for neuronal activation) was quantified in the small intestinal enteric neurons, both myenteric and submucosal, and the dorsal vagal complex (DVC) of the hindbrain. RESULTS PYY 3-36 reduced first MS, decreased IMI length, shortened duration of first meal and increased Fos-LI in enteric and DVC neurons. However, PYY 3-36 failed to change the size of the second meal, satiety ratio, latency to first meal, number of meals and 24 h intake relative to saline control. CONCLUSION The gastrointestinal tract may contain sites of action regulating MS reduction by PYY 3-36.
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Mhalhal TR, Washington MC, Newman K, Heath JC, Sayegh AI. Exogenous glucagon-like peptide-1 reduces body weight and cholecystokinin-8 enhances this reduction in diet-induced obese male rats. Physiol Behav 2017. [DOI: 10.1016/j.physbeh.2017.06.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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