251
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Hazell TJ, Islam H, Townsend LK, Schmale MS, Copeland JL. Effects of exercise intensity on plasma concentrations of appetite-regulating hormones: Potential mechanisms. Appetite 2016; 98:80-8. [DOI: 10.1016/j.appet.2015.12.016] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 12/15/2015] [Accepted: 12/16/2015] [Indexed: 01/05/2023]
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252
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Tak YJ, Yi YH, Lee SY, Kim YJ, Lee JG, Cho YH. Relationships Between Fasting Serum Amylase and Ghrelin or Peptide YY3-36 Levels in Healthy Men. Pancreas 2016; 45:376-380. [PMID: 26495778 DOI: 10.1097/mpa.0000000000000498] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
OBJECTIVES Appetite and carbohydrate metabolism are important contributors to the development of obesity. Recently, low serum amylase was shown to be associated with obesity and metabolic disorder. We investigated the relationship between amylase and ghrelin or peptide YY (PYY) levels in healthy men. METHODS Twenty-one men were enrolled in this cross-sectional study; all subjects were asymptomatic with no medical history. Fasting serum amylase, ghrelin, PYY3-36, anthropometry, and nutritional intake were measured. Linear regression analyses were performed to examine associations between amylase and ghrelin or PYY3-36. RESULTS The mean (SD) age and waist circumference of the subjects were 51.5 (10.9) years and 87.0 (4.4) cm, respectively. Amylase was found to be correlated with waist circumference (r = -0.438, P = 0.054), ghrelin (r = 0.533, P = 0.015), and PYY3-36 (r = -0.511, P = 0.021). Multivariate linear regression analysis revealed a negative association between amylase and PYY3-36 (β = -0.428, P = 0.045) but a nonsignificantly positive association between amylase and ghrelin (β = 0.260, P = 0.146). CONCLUSIONS Amylase levels were found to be associated with ghrelin and PYY3-36 in healthy men. Amylase, ghrelin, and PYY3-36 may play a role in obesity; further research is required to identify the underlying mechanism.
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Affiliation(s)
- Young Jin Tak
- From the *Department of Family Medicine, Pusan National University School of Medicine, Yangsan, South Korea; †Biomedical Research Institute, Pusan National University Hospital, Busan, South Korea; ‡Medical Education Unit, Pusan National University School of Medicine, Yangsan, South Korea; §Obesity, Nutrition and Metabolism Clinic, Department of Family Medicine, Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea; and ∥Biomedical Research Institute, Pusan National University Yangsan Hospital, Yangsan, South Korea
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253
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Breton J, Tennoune N, Lucas N, Francois M, Legrand R, Jacquemot J, Goichon A, Guérin C, Peltier J, Pestel-Caron M, Chan P, Vaudry D, do Rego JC, Liénard F, Pénicaud L, Fioramonti X, Ebenezer IS, Hökfelt T, Déchelotte P, Fetissov SO. Gut Commensal E. coli Proteins Activate Host Satiety Pathways following Nutrient-Induced Bacterial Growth. Cell Metab 2016; 23:324-34. [PMID: 26621107 DOI: 10.1016/j.cmet.2015.10.017] [Citation(s) in RCA: 220] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 07/01/2015] [Accepted: 10/27/2015] [Indexed: 01/07/2023]
Abstract
The composition of gut microbiota has been associated with host metabolic phenotypes, but it is not known if gut bacteria may influence host appetite. Here we show that regular nutrient provision stabilizes exponential growth of E. coli, with the stationary phase occurring 20 min after nutrient supply accompanied by bacterial proteome changes, suggesting involvement of bacterial proteins in host satiety. Indeed, intestinal infusions of E. coli stationary phase proteins increased plasma PYY and their intraperitoneal injections suppressed acutely food intake and activated c-Fos in hypothalamic POMC neurons, while their repeated administrations reduced meal size. ClpB, a bacterial protein mimetic of α-MSH, was upregulated in the E. coli stationary phase, was detected in plasma proportional to ClpB DNA in feces, and stimulated firing rate of hypothalamic POMC neurons. Thus, these data show that bacterial proteins produced after nutrient-induced E. coli growth may signal meal termination. Furthermore, continuous exposure to E. coli proteins may influence long-term meal pattern.
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Affiliation(s)
- Jonathan Breton
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Naouel Tennoune
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Nicolas Lucas
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Marie Francois
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Romain Legrand
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Justine Jacquemot
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Alexis Goichon
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Charlène Guérin
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Johann Peltier
- Microbiology Laboratory GRAM, EA2656, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Martine Pestel-Caron
- Microbiology Laboratory GRAM, EA2656, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France; Rouen University Hospital, CHU Charles Nicolle, Rouen 76183, France
| | - Philippe Chan
- PISSARO Proteomic Platform, Mont-Saint-Aignan 76821, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - David Vaudry
- PISSARO Proteomic Platform, Mont-Saint-Aignan 76821, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Jean-Claude do Rego
- Animal Behavior Platform (SCAC), Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France
| | - Fabienne Liénard
- Centre for Taste and Feeding Behaviour, UMR 6265-CNRS, 1324-INRA, Bourgogne Franche Comté University, Dijon F 21000, France
| | - Luc Pénicaud
- Centre for Taste and Feeding Behaviour, UMR 6265-CNRS, 1324-INRA, Bourgogne Franche Comté University, Dijon F 21000, France
| | - Xavier Fioramonti
- Centre for Taste and Feeding Behaviour, UMR 6265-CNRS, 1324-INRA, Bourgogne Franche Comté University, Dijon F 21000, France
| | - Ivor S Ebenezer
- Neuropharmacology Research Group, School of Pharmacy and Biomedical Sciences University of Portsmouth, Portsmouth PO 1 2DT, UK
| | - Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm 17176, Sweden
| | - Pierre Déchelotte
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France; Rouen University Hospital, CHU Charles Nicolle, Rouen 76183, France
| | - Sergueï O Fetissov
- Inserm UMR1073, Nutrition, Gut and Brain Laboratory, Rouen 76183, France; Institute for Research and Innovation in Biomedicine (IRIB), Rouen University, Normandy University, Rouen 76000, France.
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254
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Słupecka M, Romanowicz K, Woliński J. Maternal High-Fat Diet during Pregnancy and Lactation Influences Obestatin and Ghrelin Concentrations in Milk and Plasma of Wistar Rat Dams and Their Offspring. Int J Endocrinol 2016; 2016:5739763. [PMID: 27127509 PMCID: PMC4830745 DOI: 10.1155/2016/5739763] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/18/2016] [Accepted: 03/06/2016] [Indexed: 12/12/2022] Open
Abstract
The study aims to establish the effect of a maternal high-fat diet on obestatin concentration, total ghrelin, and ghrelin/obestatin ratio during pregnancy and lactation of Wistar rats and their offspring in the first 21 days of life. On the mating day, females were randomly allocated and fed either a high-fat diet (30% of fat; HF) or breeding diet (5% fat; BD) till the 21st day of lactation. Hormones were analyzed in the blood plasma and milk of rat dams as well as in the blood plasma of their offspring. HF resulted in a significant decrease in obestatin level on the 14th day of lactation and elevation on the 21st day. Plasma obestatin in HFD offspring was significantly higher than in BD ones. HF diet did not significantly affect dam plasma ghrelin until the 21st day of lactation. The ghrelin concentrations in milk after both diets were significantly lower than in blood plasma. Milk ghrelin in HF dams was significantly higher than in the BD ones. Plasma ghrelin from HF offspring was significantly higher than that from BD dams. Our results demonstrate that a maternal HF diet during pregnancy and lactation influences ghrelin and obestatin level in both dams and their offspring.
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Affiliation(s)
- Monika Słupecka
- Department of Endocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jabłonna, Poland
- *Monika Słupecka:
| | - Katarzyna Romanowicz
- Department of Endocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jabłonna, Poland
| | - Jarosław Woliński
- Department of Endocrinology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, 05-110 Jabłonna, Poland
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255
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Ma S, Ge Y, Gai X, Xue M, Li N, Kang J, Wan J, Zhang J. Transgenic n-3 PUFAs enrichment leads to weight loss via modulating neuropeptides in hypothalamus. Neurosci Lett 2015; 611:28-32. [PMID: 26610903 DOI: 10.1016/j.neulet.2015.11.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 11/20/2022]
Abstract
Body weight is related to fat mass, which is associated with obesity. Our study explored the effect of fat-1 gene on body weight in fat-1 transgenic mice. In present study, we observed that the weight/length ratio of fat-1 transgenic mice was lower than that of wild-type mice. The serum levels of triglycerides (TG), cholesterol (CT), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c) and blood glucose (BG) in fat-1 transgenic mice were all decreased. The weights of peri-bowels fat, perirenal fat and peri-testicular fat in fat-1 transgenic mice were reduced. We hypothesized that increase of n-3 PUFAs might alter the expression of hypothalamic neuropeptide genes and lead to loss of body weight in fat-1 transgenic mice. Therefore, we measured mRNA levels of appetite neuropeptides, Neuropeptide Y (NPY), Agouti-related peptides (AgRP), Proopiomelanocortin (POMC), Cocaine and amphetamine regulated transcript (CART), ghrelin and nesfatin-1 in hypothalamus by real-time PCR. Compared with wild-type mice, the mRNA levels of CART, POMC and ghrelin were higher, while the mRNA levels of NPY, AgRP and nesfatin-1 were lower in fat-1 transgenic mice. The results indicate that fat-1 gene or n-3 PUFAs participates in regulation of body weight, and the mechanism of this phenomenon involves the expression of appetite neuropeptides and lipoproteins in fat-1 transgenic mice.
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Affiliation(s)
- Shuangshuang Ma
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China
| | - Yinlin Ge
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China
| | - Xiaoying Gai
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China
| | - Meilan Xue
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China
| | - Ning Li
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China
| | - Jingxuan Kang
- Mathazhusazhu General Hospital, Harvard Medical College, Boston, USA
| | - Jianbo Wan
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, China
| | - Jinyu Zhang
- Department of Biochemistry and Molecular Biology, Medical College of Qingdao University, Qingdao, Shandong 266021, PR China.
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256
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Yuan D, Wei R, Wang T, Wu Y, Lin F, Chen H, Liu J, Gao Y, Zhou C, Chen D, Li Z. Appetite regulation in Schizothorax prenanti by three CART genes. Gen Comp Endocrinol 2015; 224:194-204. [PMID: 26316039 DOI: 10.1016/j.ygcen.2015.08.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 08/20/2015] [Accepted: 08/23/2015] [Indexed: 01/29/2023]
Abstract
In recent years, cocaine- and amphetamine-regulated transcript (CART) has received much attention as mediators of appetite regulation in mammals. However, the involvement of CART in the feeding behavior of teleosts has not been well understood. In this study, three distinct CARTs were cloned from the Schizothorax prenanti (S. prenanti). Real-time quantitative PCR were applied to characterize the tissue distribution and appetite regulatory effects of CARTs in S. prenanti. The S. prenanti CART-1, CART-2 and CART-3 full-length cDNA sequences were 597 bp, 694 bp and 749 bp in length, encoding the peptides of 125, 120 and 104 amino acid residues, respectively. All the S. prenanti CARTs consisted of three exons and two introns. Tissue distribution analysis showed that the high mRNA levels of S. prenanti CART-1 were observed in the telencephalon and eye, followed by the hypothalamus, myelencephalon, and mesencephalon. The S. prenanti CART-2 mRNA was mainly found in the mesencephalon, hypothalamus, telencephalon and myelencephalon. The S. prenanti CART-3 mRNA was widely distributed among the tissues, with the high levels in the hypothalamus and foregut. In the periprandial experiment, all three CARTs mRNA expressions in the hypothalamus were highly elevated after a meal, suggesting that CARTs are postprandial satiety signals. In the fasting experiment, all three CARTs mRNA expressions decreased after fasting and increased after refeeding, suggesting that CARTs might be involved in regulation of appetite in the S. prenanti.
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Affiliation(s)
- Dengyue Yuan
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China; Department of Aquaculture, College of Life Sciences, Neijiang Normal University, Neijiang, Sichuan 641000, China
| | - Rongbin Wei
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China; Department of Ophthalmology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200072, China
| | - Tao Wang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Yuanbing Wu
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Fangjun Lin
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Hu Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Ju Liu
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Yundi Gao
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Chaowei Zhou
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Defang Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China
| | - Zhiqiong Li
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan 610000, China.
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257
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Medicinal Plants and Their Inhibitory Activities against Pancreatic Lipase: A Review. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:973143. [PMID: 26640503 PMCID: PMC4657100 DOI: 10.1155/2015/973143] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 10/15/2015] [Indexed: 12/18/2022]
Abstract
Obesity is recognized as a major life style disorder especially in developing countries and it is prevailing at an alarming speed in new world countries due to fast food intake, industrialization, and reduction of physical activity. Furthermore, it is associated with a vast number of chronic diseases and disabilities. To date, relatively effective drugs, from either natural or synthetic sources, are generally associated with serious side effects, often leading to cessation of clinical trials or even withdrawal from the market. In order to find new compounds which are more effective or with less adverse effects compared to orlistat, the drug that has been approved for obesity, new compounds isolated from natural products are being identified and screened for antiobesity effects, in particular, for their pancreatic lipase inhibitory effect. Pancreatic lipase inhibitory activity has been extensively used for the determination of potential efficacy of natural products as antiobesity agents. In attempts to identify natural products for overcoming obesity, more researches have been focused on the identification of newer pancreatic lipase inhibitors with less unpleasant adverse effects. In this review, we consider the potential role of plants that have been investigated for their pancreatic lipase inhibitory activity.
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258
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Rebello CJ, Burton J, Heiman M, Greenway FL. Gastrointestinal microbiome modulator improves glucose tolerance in overweight and obese subjects: A randomized controlled pilot trial. J Diabetes Complications 2015; 29:1272-6. [PMID: 26424589 PMCID: PMC4656110 DOI: 10.1016/j.jdiacomp.2015.08.023] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/24/2015] [Accepted: 08/30/2015] [Indexed: 12/15/2022]
Abstract
OBJECTIVE The objective of this study was to examine the effects of a gastrointestinal microbiome modulator (GIMM) containing inulin, β-glucan, blueberry anthocyanins, and blueberry polyphenols on metabolic parameters, fecal markers of gut microbiota, and satiety. DESIGN AND METHODS Thirty overweight or obese individuals aged 18 to 70years, were enrolled in a randomized controlled trial. Participants consumed the test product or placebo daily for four weeks. Stool samples were collected and blood was drawn at baseline and week four for assessments of gut microbiota, satiety hormones, glucose control, and lipid measures. Subjective satiety was assessed weekly. Linear models were used to compare differences from baseline to week four. RESULTS GIMM consumption improved blood glucose tolerance (p=0.008), and increased satiety (p=0.03). There were no statistically significant differences in insulin sensitivity, fecal markers of gut microbiota, plasma satiety hormones, or serum lipid concentrations between the groups. However, plasma satiety hormones and fecal short chain fatty acid concentrations increased in the test group compared to the placebo. CONCLUSIONS GIMM consumption for four weeks, increases satiety, and improves glucose tolerance possibly through insulin-independent pathways.
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Affiliation(s)
- Candida J Rebello
- Pennington Biomedical Research Center, Louisiana State University System, 6400, Perkins Road Baton Rouge, LA 70808, USA; School of Nutrition and Food Sciences, Louisiana State University, Baton Rouge, LA 70803, USA.
| | - Jeffrey Burton
- Pennington Biomedical Research Center, Louisiana State University System, 6400, Perkins Road Baton Rouge, LA 70808, USA.
| | - Mark Heiman
- MicroBiome Therapeutics LLC, 1316 Jefferson Ave., New Orleans, LA 70115, USA.
| | - Frank L Greenway
- Pennington Biomedical Research Center, Louisiana State University System, 6400, Perkins Road Baton Rouge, LA 70808, USA.
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259
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Abstract
The contribution of intestinal bacterial strains (gut microbiota) to the development of obesity and obesity-related disorders is increasingly recognized as a potential diagnostic and pharmacologic target. Alterations in the intestinal bacterial composition have been associated with presence of chronic low-grade inflammation, a known feature of insulin resistance and type 2 diabetes mellitus. However, causality still needs to be proven. Fecal transplantation studies in germ-free mice have provided crucial insight into the causality of gut microbiota in development of obesity and obesity-related disorders. Moreover, fecal transplantation studies in conjunction with fecal sampling in prospectively followed cohorts will help identify causally involved intestinal bacterial strains in human obesity. Results from these studies will lead to characterization of novel diagnostic markers as well as therapeutic strategies that aim to treat obesity and obesity-related disorders.
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260
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Chambers ES, Viardot A, Psichas A, Morrison DJ, Murphy KG, Zac-Varghese SEK, MacDougall K, Preston T, Tedford C, Finlayson GS, Blundell JE, Bell JD, Thomas EL, Mt-Isa S, Ashby D, Gibson GR, Kolida S, Dhillo WS, Bloom SR, Morley W, Clegg S, Frost G. Effects of targeted delivery of propionate to the human colon on appetite regulation, body weight maintenance and adiposity in overweight adults. Gut 2015; 64:1744-54. [PMID: 25500202 PMCID: PMC4680171 DOI: 10.1136/gutjnl-2014-307913] [Citation(s) in RCA: 850] [Impact Index Per Article: 94.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 09/05/2014] [Accepted: 09/23/2014] [Indexed: 12/17/2022]
Abstract
OBJECTIVE The colonic microbiota ferment dietary fibres, producing short chain fatty acids. Recent evidence suggests that the short chain fatty acid propionate may play an important role in appetite regulation. We hypothesised that colonic delivery of propionate would increase peptide YY (PYY) and glucagon like peptide-1 (GLP-1) secretion in humans, and reduce energy intake and weight gain in overweight adults. DESIGN To investigate whether propionate promotes PYY and GLP-1 secretion, a primary cultured human colonic cell model was developed. To deliver propionate specifically to the colon, we developed a novel inulin-propionate ester. An acute randomised, controlled cross-over study was used to assess the effects of this inulin-propionate ester on energy intake and plasma PYY and GLP-1 concentrations. The long-term effects of inulin-propionate ester on weight gain were subsequently assessed in a randomised, controlled 24-week study involving 60 overweight adults. RESULTS Propionate significantly stimulated the release of PYY and GLP-1 from human colonic cells. Acute ingestion of 10 g inulin-propionate ester significantly increased postprandial plasma PYY and GLP-1 and reduced energy intake. Over 24 weeks, 10 g/day inulin-propionate ester supplementation significantly reduced weight gain, intra-abdominal adipose tissue distribution, intrahepatocellular lipid content and prevented the deterioration in insulin sensitivity observed in the inulin-control group. CONCLUSIONS These data demonstrate for the first time that increasing colonic propionate prevents weight gain in overweight adult humans. TRIAL REGISTRATION NUMBER NCT00750438.
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Affiliation(s)
- Edward S Chambers
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Imperial College London, 6th Floor Commonwealth Building, Hammersmith Hospital, London, UK
| | - Alexander Viardot
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Imperial College London, 6th Floor Commonwealth Building, Hammersmith Hospital, London, UK
- Diabetes and Metabolism Division, Garvan Institute of Medical Research, Darlinghurst, NSW 2010, Australia
| | - Arianna Psichas
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Imperial College London, 6th Floor Commonwealth Building, Hammersmith Hospital, London, UK
| | - Douglas J Morrison
- Stable Isotope Biochemistry Laboratory, Scottish Universities Environmental Research Centre, University of Glasgow, Glasgow, UK
| | - Kevin G Murphy
- Section of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | - Sagen E K Zac-Varghese
- Section of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | | | - Tom Preston
- Stable Isotope Biochemistry Laboratory, Scottish Universities Environmental Research Centre, University of Glasgow, Glasgow, UK
| | - Catriona Tedford
- School of Science, University of the West of Scotland, Hamilton, UK
| | | | - John E Blundell
- Institute of Psychological Sciences, University of Leeds, Leeds, UK
| | - Jimmy D Bell
- Metabolic and Molecular Imaging Research Group, MRC Clinical Science Centre, Imperial College London, Hammersmith Hospital, London, UK
| | - E Louise Thomas
- Metabolic and Molecular Imaging Research Group, MRC Clinical Science Centre, Imperial College London, Hammersmith Hospital, London, UK
| | - Shahrul Mt-Isa
- Imperial Clinical Trials Unit, School of Public Health, Imperial College London, London, UK
| | - Deborah Ashby
- Imperial Clinical Trials Unit, School of Public Health, Imperial College London, London, UK
| | - Glen R Gibson
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Sofia Kolida
- Department of Food and Nutritional Sciences, University of Reading, Reading, UK
| | - Waljit S Dhillo
- Section of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | - Stephen R Bloom
- Section of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, UK
| | - Wayne Morley
- Leatherhead Food Research, Randall's Road Leatherhead, Surrey, UK
| | - Stuart Clegg
- Leatherhead Food Research, Randall's Road Leatherhead, Surrey, UK
| | - Gary Frost
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Imperial College London, 6th Floor Commonwealth Building, Hammersmith Hospital, London, UK
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261
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Ritze Y, Hengelhaupt C, Bárdos G, Ernst B, Thurnheer M, D'Haese JG, Bischoff SC, Schultes B. Altered intestinal neuroendocrine gene expression in humans with obesity. Obesity (Silver Spring) 2015; 23:2278-85. [PMID: 26381270 DOI: 10.1002/oby.21253] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/01/2015] [Accepted: 07/12/2015] [Indexed: 12/16/2022]
Abstract
OBJECTIVE Gastrointestinal hormones are critically involved in the regulation of food intake and body weight. Previous studies support an interplay between gastrointestinal hormones and the serotonergic system. This study explored intestinal neuroendocrine expression patterns in humans with obesity versus nonobese humans. METHODS Jejunum samples were collected from 164 humans with obesity (120 women; BMI (mean ± SD): 43.5 ± 6.6 kg/m(2) ) while they underwent Roux-en-Y gastric bypass surgery and from 18 nonobese humans (7 women; BMI: 23.5 ± 3.0 kg/m(2) ) undergoing distinct intestinal surgeries. mRNA expression of cholecystokinin (CCK), peptide YY3-36 (PYY), nesfatin1, ghrelin, ghrelin O-acyltransferase (GOAT), leptin, leptin receptor (leptinR), glucagon-like-peptide 1 receptor (GLP1R), serotonin transporter (SERT), tryptophan hydroxylase 1 (TPH1), and serotonin receptor 3A (5HT3A R) was determined with qRT-PCR. Ghrelin and GOAT protein expression was quantified using immunohistological stainings. Statistical analyses were performed with SPSS. RESULTS Jejunum samples from humans with obesity showed a higher expression of GOAT (mRNA and protein), TPH1, and SERT mRNA compared with the nonobese humans (all P < 0.05). Positive correlations were observed between TPH1, CCK, PYY, and nesfatin1 in nonobese and GOAT, ghrelin, TPH1, SERT, CCK, and PYY in humans with obesity (all P < 0.01). CONCLUSIONS Our top-down approach substantiates the dysregulation of jejunal neuroendocrine hormones in obesity.
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Affiliation(s)
- Yvonne Ritze
- Department of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany
| | | | - Gyöngyi Bárdos
- Department of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany
| | - Barbara Ernst
- eSwiss Medical and Surgical Center, Interdisciplinary Obesity Center, St. Gallen, Switzerland
| | - Martin Thurnheer
- eSwiss Medical and Surgical Center, Interdisciplinary Obesity Center, St. Gallen, Switzerland
| | - Jan G D'Haese
- Department of Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Stephan C Bischoff
- Department of Nutritional Medicine, University of Hohenheim, Stuttgart, Germany
| | - Bernd Schultes
- eSwiss Medical and Surgical Center, Interdisciplinary Obesity Center, St. Gallen, Switzerland
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262
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Ralevski A, Horvath TL. Developmental programming of hypothalamic neuroendocrine systems. Front Neuroendocrinol 2015; 39:52-8. [PMID: 26391503 DOI: 10.1016/j.yfrne.2015.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 09/17/2015] [Accepted: 09/17/2015] [Indexed: 12/30/2022]
Abstract
There is increasing evidence to suggest that the perinatal environment may alter the developmental programming of hypothalamic neuroendocrine systems in a manner that predisposes offspring to the development of metabolic syndrome. Although it is unclear how these effects might be mediated, it has been shown that changes in neuroendocrine programing during critical periods of development, either via maternal metabolic programming or other factors, can alter a fetus's metabolic fate. This review summarizes the hypothalamic circuits that mediate energy homeostasis and discusses the various factors that may influence the development and functioning of these neural systems, as well as the possible cognitive impairments that may arise as a result of these metabolic influences.
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Affiliation(s)
- Alexandra Ralevski
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06510, USA.
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263
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Abstract
The connection between the gut microbiota and the aetiology of obesity and cardiometabolic disorders is increasingly being recognized by clinicians. Our gut microbiota might affect the cardiometabolic phenotype by fermenting indigestible dietary components and thereby producing short-chain fatty acids (SCFA). These SCFA are not only of importance in gut health and as signalling molecules, but might also enter the systemic circulation and directly affect metabolism or the function of peripheral tissues. In this Review, we discuss the effects of three SCFA (acetate, propionate and butyrate) on energy homeostasis and metabolism, as well as how these SCFA can beneficially modulate adipose tissue, skeletal muscle and liver tissue function. As a result, these SCFA contribute to improved glucose homeostasis and insulin sensitivity. Furthermore, we also summarize the increasing evidence for a potential role of SCFA as metabolic targets to prevent and counteract obesity and its associated disorders in glucose metabolism and insulin resistance. However, most data are derived from animal and in vitro studies, and consequently the importance of SCFA and differential SCFA availability in human energy and substrate metabolism remains to be fully established. Well-controlled human intervention studies investigating the role of SCFA on cardiometabolic health are, therefore, eagerly awaited.
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Affiliation(s)
- Emanuel E Canfora
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitssingel 50, 6229 ER, Maastricht, PO Box 616, 6200 MD, Maastricht, Netherlands
| | - Johan W Jocken
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitssingel 50, 6229 ER, Maastricht, PO Box 616, 6200 MD, Maastricht, Netherlands
| | - Ellen E Blaak
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Universiteitssingel 50, 6229 ER, Maastricht, PO Box 616, 6200 MD, Maastricht, Netherlands
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264
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Al-Saffar A, Nogueira da Costa A, Delaunois A, Leishman DJ, Marks L, Rosseels ML, Valentin JP. Gastrointestinal Safety Pharmacology in Drug Discovery and Development. Handb Exp Pharmacol 2015; 229:291-321. [PMID: 26091645 DOI: 10.1007/978-3-662-46943-9_12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although the basic structure of the gastrointestinal tract (GIT) is similar across species, there are significant differences in the anatomy, physiology, and biochemistry between humans and laboratory animals, which should be taken into account when conducting a gastrointestinal (GI) assessment. Historically, the percentage of cases of drug attrition associated with GI-related adverse effects is small; however, this incidence has increased over the last few years. Drug-related GI effects are very diverse, usually functional in nature, and not limited to a single pharmacological class. The most common GI signs are nausea and vomiting, diarrhea, constipation, and gastric ulceration. Despite being generally not life-threatening, they can greatly affect patient compliance and quality of life. There is therefore a real need for improved and/or more extensive GI screening of candidate drugs in preclinical development, which may help to better predict clinical effects. Models to identify drug effects on GI function cover GI motility, nausea and emesis liability, secretory function (mainly gastric secretion), and absorption aspects. Both in vitro and in vivo assessments are described in this chapter. Drug-induced effects on GI function can be assessed in stand-alone safety pharmacology studies or as endpoints integrated into toxicology studies. In silico approaches are also being developed, such as the gut-on-a-chip model, but await further optimization and validation before routine use in drug development. GI injuries are still in their infancy with regard to biomarkers, probably due to their greater diversity. Nevertheless, several potential blood, stool, and breath biomarkers have been investigated. However, additional validation studies are necessary to assess the relevance of these biomarkers and their predictive value for GI injuries.
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Affiliation(s)
- Ahmad Al-Saffar
- Faculty of Medicine, Department of Medical Sciences, Uppsala University, 751 85, Uppsala, Sweden
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265
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Abstract
Unhealthy dietary behaviours may contribute to obesity along with energy imbalance. Both positive and null associations of snacking and BMI have been reported, but the association between snacking and total adiposity or pattern of fat deposition remains unevaluated. The objective of this study was to investigate the associations between snacking frequency and detailed adiposity measurements. A total of 10 092 adults residing in Cambridgeshire, England, self-completed eating pattern snacking frequency, FFQ and physical activity questionnaires. Measurements included anthropometry, body composition using dual-energy X-ray absorptiometry scan and ultrasound and assessment of physical activity energy expenditure using heart rate and movement sensing. Linear regression analyses were conducted adjusted for age, socio-demographics, dietary quality, energy intake, PAEE and screen time by sex and BMI status. Among normal-weight individuals (BMI<25 kg/m2), each additional snack was inversely associated with obesity measures: lower total body fat in men and women (−0·41 (95 % CI −0·74, −0·07) %, −0·41 (−0·67, −0·15) %, respectively) and waist circumference (−0·52 (−0·90, −0·14) cm) in men. In contrast, among the overweight/obese (BMI≥25 kg/m2), there were positive associations: higher waist circumference (0·80 (0·34, 0·28) cm) and subcutaneous fat (0·06 (0·01, 0·110) cm) in women and waist circumference (0·37 (0·00, 0·73) cm) in men. Comparing intakes of snack-type foods showed that participants with BMI≥25 kg/m2 had higher intakes of crisps, sweets, chocolates and ice-creams and lower intakes of yoghurt and nuts compared with normal-weight participants. Adjusting for these foods in a model that included a BMI–snacking interaction term attenuated all the associations to null. Snacking frequency may be associated with higher or lower adiposity, with the direction of association being differential by BMI status and dependent on snack food choice. Improving snack choices could contribute to anti-obesity public health interventions.
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266
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Bleau C, Karelis AD, St-Pierre DH, Lamontagne L. Crosstalk between intestinal microbiota, adipose tissue and skeletal muscle as an early event in systemic low-grade inflammation and the development of obesity and diabetes. Diabetes Metab Res Rev 2015; 31:545-61. [PMID: 25352002 DOI: 10.1002/dmrr.2617] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 10/01/2014] [Accepted: 10/13/2014] [Indexed: 02/06/2023]
Abstract
Obesity is associated with a systemic chronic low-grade inflammation that contributes to the development of metabolic disorders such as cardiovascular diseases and type 2 diabetes. However, the etiology of this obesity-related pro-inflammatory process remains unclear. Most studies have focused on adipose tissue dysfunctions and/or insulin resistance in skeletal muscle cells as well as changes in adipokine profile and macrophage recruitment as potential sources of inflammation. However, low-grade systemic inflammation probably involves a complex network of signals interconnecting several organs. Recent evidences have suggested that disturbances in the composition of the gut microbial flora and alterations in levels of gut peptides following the ingestion of a high-fat diet may be a cause of low-grade systemic inflammation that may even precede and predispose to obesity, metabolic disorders or type 2 diabetes. This hypothesis is appealing because the gastrointestinal system is first exposed to nutrients and may thereby represent the first link in the chain of events leading to the development of obesity-associated systemic inflammation. Therefore, the present review will summarize the latest advances interconnecting intestinal mucosal bacteria-mediated inflammation, adipose tissue and skeletal muscle in a coordinated circuitry favouring the onset of a high-fat diet-related systemic low-grade inflammation preceding obesity and predisposing to metabolic disorders and/or type 2 diabetes. A particular emphasis will be given to high-fat diet-induced alterations of gut homeostasis as an early initiator event of mucosal inflammation and adverse consequences contributing to the promotion of extended systemic inflammation, especially in adipose and muscular tissues.
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MESH Headings
- Adipose Tissue, White/immunology
- Adipose Tissue, White/metabolism
- Animals
- Diabetes Mellitus, Type 2/etiology
- Diabetes Mellitus, Type 2/immunology
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/microbiology
- Diet, High-Fat/adverse effects
- Enteritis/etiology
- Enteritis/immunology
- Enteritis/microbiology
- Enteritis/physiopathology
- Gastrointestinal Hormones/metabolism
- Gastrointestinal Microbiome
- Humans
- Immunity, Mucosal
- Intestinal Mucosa/immunology
- Intestinal Mucosa/metabolism
- Intestinal Mucosa/microbiology
- Models, Biological
- Muscle, Skeletal/immunology
- Muscle, Skeletal/metabolism
- Myositis/etiology
- Myositis/immunology
- Myositis/microbiology
- Myositis/physiopathology
- Obesity/etiology
- Obesity/immunology
- Obesity/metabolism
- Obesity/microbiology
- Panniculitis/etiology
- Panniculitis/immunology
- Panniculitis/microbiology
- Panniculitis/physiopathology
- Systemic Vasculitis/etiology
- Systemic Vasculitis/immunology
- Systemic Vasculitis/microbiology
- Systemic Vasculitis/physiopathology
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Affiliation(s)
- Christian Bleau
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, Canada, H3C 3P8
| | - Antony D Karelis
- Department of Kinanthropology, Université du Québec à Montréal, Montreal, Canada, H3C 3P8
| | - David H St-Pierre
- Department of Kinanthropology, Université du Québec à Montréal, Montreal, Canada, H3C 3P8
| | - Lucie Lamontagne
- Department of Biological Sciences, Université du Québec à Montréal, Montreal, Canada, H3C 3P8
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267
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Singh AK, Kota SK. Bariatric surgery and diabetes remission: how far have we progressed? Expert Rev Endocrinol Metab 2015; 10:545-559. [PMID: 30298760 DOI: 10.1586/17446651.2015.1073586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Obesity and type 2 diabetes mellitus have been associated with higher morbidity and mortality. Bariatric surgery results in substantial and sustained weight loss in morbidly obese patients and improves obstructive sleep apnea. Furthermore, bariatric surgery improves diabetes control, hypertension, quality of life, stroke, myocardial infarction and reduces mortality. Interestingly, bariatric surgery induces high rates of short and long-term diabetes remission. While the exact mechanisms behind this are not completely understood, improved insulin action, β-cell function and a complex interplay of hormones in the entero-insular axis appear to play major roles. Insulin action improves proportionally to weight loss and it gets completely normalized especially after bilio-pancreatic diversion. β-Cell function also seems to improve after a variety of bariatric surgeries. Seemingly, baseline β-cell function is able to predict future diabetes remission. This article will review the effectiveness of bariatric procedures on the remission and improvement of diabetes and its implicated mechanisms.
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268
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Chambers ES, Morrison DJ, Tedford MC, Frost G. A novel dietary strategy to increase colonic propionate production in humans and improve appetite regulation and bodyweight management. NUTR BULL 2015. [DOI: 10.1111/nbu.12157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- E. S. Chambers
- Nutrition and Dietetic Research GroupSection of Investigative MedicineFaculty of MedicineImperial College London London UK
| | - D. J. Morrison
- Stable Isotope Biochemistry LaboratoryScottish Universities Environmental Research CentreUniversity of Glasgow Glasgow UK
| | - M. C. Tedford
- School of ScienceUniversity of the West of Scotland Hamilton UK
| | - G. Frost
- Nutrition and Dietetic Research GroupSection of Investigative MedicineFaculty of MedicineImperial College London London UK
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269
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Affiliation(s)
- R. Miller
- British Nutrition Foundation London UK
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270
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den Besten G, Gerding A, van Dijk TH, Ciapaite J, Bleeker A, van Eunen K, Havinga R, Groen AK, Reijngoud DJ, Bakker BM. Protection against the Metabolic Syndrome by Guar Gum-Derived Short-Chain Fatty Acids Depends on Peroxisome Proliferator-Activated Receptor γ and Glucagon-Like Peptide-1. PLoS One 2015; 10:e0136364. [PMID: 26292284 PMCID: PMC4546369 DOI: 10.1371/journal.pone.0136364] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 07/31/2015] [Indexed: 12/20/2022] Open
Abstract
The dietary fiber guar gum has beneficial effects on obesity, hyperglycemia and hypercholesterolemia in both humans and rodents. The major products of colonic fermentation of dietary fiber, the short-chain fatty acids (SCFAs), have been suggested to play an important role. Recently, we showed that SCFAs protect against the metabolic syndrome via a signaling cascade that involves peroxisome proliferator-activated receptor (PPAR) γ repression and AMP-activated protein kinase (AMPK) activation. In this study we investigated the molecular mechanism via which the dietary fiber guar gum protects against the metabolic syndrome. C57Bl/6J mice were fed a high-fat diet supplemented with 0% or 10% of the fiber guar gum for 12 weeks and effects on lipid and glucose metabolism were studied. We demonstrate that, like SCFAs, also guar gum protects against high-fat diet-induced metabolic abnormalities by PPARγ repression, subsequently increasing mitochondrial uncoupling protein 2 expression and AMP/ATP ratio, leading to the activation of AMPK and culminating in enhanced oxidative metabolism in both liver and adipose tissue. Moreover, guar gum markedly increased peripheral glucose clearance, possibly mediated by the SCFA-induced colonic hormone glucagon-like peptide-1. Overall, this study provides novel molecular insights into the beneficial effects of guar gum on the metabolic syndrome and strengthens the potential role of guar gum as a dietary-fiber intervention.
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Affiliation(s)
- Gijs den Besten
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
| | - Albert Gerding
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Theo H. van Dijk
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jolita Ciapaite
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Aycha Bleeker
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Top Institute Food and Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands
| | - Karen van Eunen
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Top Institute Food and Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands
| | - Rick Havinga
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Albert K. Groen
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Top Institute Food and Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands
| | - Dirk-Jan Reijngoud
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Laboratory Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Top Institute Food and Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands
| | - Barbara M. Bakker
- Center for Liver, Digestive and Metabolic Diseases, Department of Pediatrics & Systems Biology Center for Energy Metabolism and Ageing, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Netherlands Consortium for Systems Biology, Amsterdam, The Netherlands
- Top Institute Food and Nutrition, P.O. Box 557, 6700 AN Wageningen, The Netherlands
- * E-mail:
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271
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Wysokiński A, Sobów T, Kłoszewska I, Kostka T. Mechanisms of the anorexia of aging-a review. AGE (DORDRECHT, NETHERLANDS) 2015; 37:9821. [PMID: 26232135 PMCID: PMC5005824 DOI: 10.1007/s11357-015-9821-x] [Citation(s) in RCA: 131] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 07/22/2015] [Indexed: 05/05/2023]
Abstract
Many, even healthy, older people fail to adequately regulate food intake and experience loss of weight. Aging-associated changes in the regulation of appetite and the lack of hunger have been termed as the anorexia of aging. The etiology of the anorexia of aging is multi-factorial and includes a combination of physiological changes associated with aging (decline in smell and taste, reduced central and peripheral drive to eat, delayed gastric emptying), pathological conditions (depression, dementia, somatic diseases, medications and iatrogenic interventions, oral-health status), and social factors (poverty, loneliness). However, exact mechanisms of the anorexia of aging remain to be elucidated. Many neurobiological mechanisms may be secondary to age-related changes in body composition and not associated with anorexia per se. Therefore, further studies on pathophysiological mechanisms of the anorexia of aging should employ accurate measurement of body fat and lean mass. The anorexia of aging is associated with protein-energy malnutrition, sarcopenia, frailty, functional deterioration, morbidity, and mortality. Since this symptom can lead to dramatic consequences, early identification and effective interventions are needed. One of the most important goals in the geriatric care is to optimize nutritional status of the elderly.
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Affiliation(s)
- Adam Wysokiński
- Department of Old Age Psychiatry and Psychotic Disorders, Medical University of Lodz, Czechosłowacka 8/10, 92-216, Łódź, Poland,
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272
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Abedelmalek S, Denguezli M, Chtourou H, Souissi N, Tabka Z. Does Ramadan fasting affect acylated ghrelin and growth hormone concentrations during short-term maximal exercise in the afternoon? BIOL RHYTHM RES 2015. [DOI: 10.1080/09291016.2015.1048949] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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273
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Reviewing the Effects of L-Leucine Supplementation in the Regulation of Food Intake, Energy Balance, and Glucose Homeostasis. Nutrients 2015; 7:3914-37. [PMID: 26007339 PMCID: PMC4446786 DOI: 10.3390/nu7053914] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 04/30/2015] [Accepted: 05/12/2015] [Indexed: 12/18/2022] Open
Abstract
Leucine is a well-known activator of the mammalian target of rapamycin (mTOR). Because mTOR signaling regulates several aspects of metabolism, the potential of leucine as a dietary supplement for treating obesity and diabetes mellitus has been investigated. The objective of the present review was to summarize and discuss the available evidence regarding the mechanisms and the effects of leucine supplementation on the regulation of food intake, energy balance, and glucose homeostasis. Based on the available evidence, we conclude that although central leucine injection decreases food intake, this effect is not well reproduced when leucine is provided as a dietary supplement. Consequently, no robust evidence indicates that oral leucine supplementation significantly affects food intake, although several studies have shown that leucine supplementation may help to decrease body adiposity in specific conditions. However, more studies are necessary to assess the effects of leucine supplementation in already-obese subjects. Finally, although several studies have found that leucine supplementation improves glucose homeostasis, the underlying mechanisms involved in these potential beneficial effects remain unknown and may be partially dependent on weight loss.
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274
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Mortazavi S, Gonzalez R, Ceddia R, Unniappan S. Long-term infusion of nesfatin-1 causes a sustained regulation of whole-body energy homeostasis of male Fischer 344 rats. Front Cell Dev Biol 2015; 3:22. [PMID: 25905102 PMCID: PMC4389570 DOI: 10.3389/fcell.2015.00022] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 03/15/2015] [Indexed: 11/13/2022] Open
Abstract
Nesfatin-1, the N-terminal fragment of nucleobindin 2 (NUCB2), is an 82 amino-acid peptide that inhibits food intake and exerts weight-reducing effects. Nesfatin-1 has been proposed as a potential anti-obesity peptide. However, studies to date have mainly focused on the acute satiety effects of centrally administered nesfatin-1. The main objective of our studies was to characterize the long-term/chronic effects of peripheral administration of nesfatin-1 on whole-body energy balance and metabolic partitioning in male Fischer 344 rats. Short-term (1 day) subcutaneous infusion of nesfatin-1 (50 μg/kg body weight/day) using osmotic mini-pumps increased spontaneous physical activity and whole-body fat oxidation during the dark phase. This was accompanied by decreased food intake and basal metabolic rate compared to saline infused controls. On the seventh day of nesfatin-1 infusion, cumulative food intake, and total spontaneous physical activity during the dark phase were significantly reduced and elevated, respectively. Meanwhile, intraperitoneal injection of nesfatin-1 only caused a dark phase specific reduction in food intake and an increase in physical activity. NUCB2 mRNA expression in the brain and stomach, as well as serum NUCB2 concentrations were significantly reduced after 24 h fasting, while a post-prandial increase in serum NUCB2 was found in ad libitum fed rats. Collectively, our results indicate that chronic peripheral administration of nesfatin-1 at the dose tested, results in a sustained reduction in food intake and modulation of whole body energy homeostasis.
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Affiliation(s)
- Sima Mortazavi
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan Saskatoon, SK, Canada
| | - Ronald Gonzalez
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan Saskatoon, SK, Canada
| | - Rolando Ceddia
- School of Kinesiology and Health Sciences, York University Toronto, ON, Canada
| | - Suraj Unniappan
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan Saskatoon, SK, Canada
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275
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Liu Y, Luo J, Carlsson MA, Nässel DR. Serotonin and insulin-like peptides modulate leucokinin-producing neurons that affect feeding and water homeostasis in Drosophila. J Comp Neurol 2015; 523:1840-63. [PMID: 25732325 DOI: 10.1002/cne.23768] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 02/25/2015] [Accepted: 02/25/2015] [Indexed: 01/01/2023]
Abstract
Metabolic homeostasis and water balance is maintained by tight hormonal and neuronal regulation. In Drosophila, insulin-like peptides (DILPs) are key regulators of metabolism, and the neuropeptide leucokinin (LK) is a diuretic hormone that also modulates feeding. However, it is not known whether LK and DILPs act together to regulate feeding and water homeostasis. Because LK neurons express the insulin receptor (dInR), we tested functional links between DILP and LK signaling in feeding and water balance. Thus, we performed constitutive and conditional manipulations of activity in LK neurons and insulin-producing cells (IPCs) in adult flies and monitored food intake, responses to desiccation, and peptide expression levels. We also measured in vivo changes in LK and DILP levels in neurons in response to desiccation and drinking. Our data show that activated LK cells stimulate diuresis in vivo, and that LK and IPC signaling affect food intake in opposite directions. Overexpression of the dInR in LK neurons decreases the LK peptide levels, but only caused a subtle decrease in feeding, and had no effect on water balance. Next we demonstrated that LK neurons express the serotonin receptor 5-HT1B . Knockdown of this receptor in LK neurons diminished LK expression, increased desiccation resistance, and diminished food intake. Live calcium imaging indicates that serotonin inhibits spontaneous activity in abdominal LK neurons. Our results suggest that serotonin via 5-HT1B diminishes activity in the LK neurons and thereby modulates functions regulated by LK peptide, but the action of the dInR in these neurons remains less clear.
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Affiliation(s)
- Yiting Liu
- Department of Zoology, Stockholm University, S-10691, Stockholm, Sweden
| | - Jiangnan Luo
- Department of Zoology, Stockholm University, S-10691, Stockholm, Sweden
| | - Mikael A Carlsson
- Department of Zoology, Stockholm University, S-10691, Stockholm, Sweden
| | - Dick R Nässel
- Department of Zoology, Stockholm University, S-10691, Stockholm, Sweden
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276
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von Hausswolff-Juhlin Y, Brooks SJ, Larsson M. The neurobiology of eating disorders--a clinical perspective. Acta Psychiatr Scand 2015; 131:244-55. [PMID: 25223374 DOI: 10.1111/acps.12335] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/18/2014] [Indexed: 12/16/2022]
Abstract
OBJECTIVE To provide a neurobiological basis of eating disorders for clinicians and to enlighten how comparing neurobiology and eating disorders with neurobiology of other psychiatric illnesses can improve treatment protocols. METHOD A selective review on the neurobiology of eating disorders. The article focuses on clinical research on humans with consideration of the anatomical, neural, and molecular basis of eating disorders. RESULTS The neurobiology of people with eating disorders is altered. Many of the neurobiological regions, receptors, and chemical substrates that are affected in other mental illnesses also play an important role in eating disorders. More knowledge about the neurobiological overlap between eating disorders and other psychiatric populations will help when developing treatment protocols not the least regarding that comorbidity is common in patients with EDs. CONCLUSION Knowledge about the underlying neurobiology of eating disorders will improve treatment intervention and will benefit from comparisons with other mental illnesses and their treatments.
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Affiliation(s)
- Y von Hausswolff-Juhlin
- Center for Psychiatry Research, Karolinska Institute, Stockholm, Sweden; Stockholm Centre for Eating Disorders, Stockholm, Sweden
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277
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Abstract
Fat is a vital macronutrient, and its intake is closely monitored by an array of molecular sensors distributed throughout the alimentary canal. In the mouth, dietary fat constituents such as mono- and diunsaturated fatty acids give rise to taste signals that stimulate food intake, in part by enhancing the production of lipid-derived endocannabinoid messengers in the gut. As fat-containing chyme enters the small intestine, it causes the formation of anorexic lipid mediators, such as oleoylethanolamide, which promote satiety. These anatomically and functionally distinct responses may contribute to the homeostatic control and, possibly, the pathological dysregulation of food intake.
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Affiliation(s)
| | - Daniele Piomelli
- Departments of Anatomy and Neurobiology
- Department of Pharmacology, and
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, Irvine, California, USA
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy
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278
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Farzi A, Reichmann F, Holzer P. The homeostatic role of neuropeptide Y in immune function and its impact on mood and behaviour. Acta Physiol (Oxf) 2015; 213:603-27. [PMID: 25545642 DOI: 10.1111/apha.12445] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 11/10/2014] [Accepted: 12/21/2014] [Indexed: 12/18/2022]
Abstract
Neuropeptide Y (NPY), one of the most abundant peptides in the nervous system, exerts its effects via five receptor types, termed Y1, Y2, Y4, Y5 and Y6. NPY's pleiotropic functions comprise the regulation of brain activity, mood, stress coping, ingestion, digestion, metabolism, vascular and immune function. Nerve-derived NPY directly affects immune cells while NPY also acts as a paracrine and autocrine immune mediator, because immune cells themselves are capable of producing and releasing NPY. NPY is able to induce immune activation or suppression, depending on a myriad of factors such as the Y receptors activated and cell types involved. There is an intricate relationship between psychological stress, mood disorders and the immune system. While stress represents a risk factor for the development of mood disorders, it exhibits diverse actions on the immune system as well. Conversely, inflammation is regarded as an internal stressor and is increasingly recognized to contribute to the pathogenesis of mood and metabolic disorders. Intriguingly, the cerebral NPY system has been found to protect against distinct disturbances in response to immune challenge, attenuating the sickness response and preventing the development of depression. Thus, NPY plays an important homeostatic role in balancing disturbances of physiological systems caused by peripheral immune challenge. This implication is particularly evident in the brain in which NPY counteracts the negative impact of immune challenge on mood, emotional processing and stress resilience. NPY thus acts as a unique signalling molecule in the interaction of the immune system with the brain in health and disease.
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Affiliation(s)
- A. Farzi
- Research Unit of Translational Neurogastroenterology; Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - F. Reichmann
- Research Unit of Translational Neurogastroenterology; Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
| | - P. Holzer
- Research Unit of Translational Neurogastroenterology; Institute of Experimental and Clinical Pharmacology; Medical University of Graz; Graz Austria
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279
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Hill NE, Fallowfield JL, Delves SK, Ardley C, Stacey M, Ghatei M, Bloom SR, Frost G, Brett SJ, Wilson DR, Murphy KG. Changes in gut hormones and leptin in military personnel during operational deployment in Afghanistan. Obesity (Silver Spring) 2015; 23:608-14. [PMID: 25612171 DOI: 10.1002/oby.21000] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Accepted: 11/19/2014] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Understanding the mechanisms that drive weight loss in a lean population may elucidate systems that regulate normal energy homeostasis. This prospective study of British military volunteers investigated the effects of a 6-month deployment to Afghanistan on energy balance and circulating concentrations of specific appetite-regulating hormones. METHODS Measurements were obtained twice in the UK (during the Pre-deployment period) and once in Afghanistan, at Mid-deployment. Body mass, body composition, food intake, and appetite-regulatory hormones (leptin, active and total ghrelin, PYY, PP, GLP-1) were measured. RESULTS Repeated measures analysis of 105 volunteers showed body mass decreased by 4.9% ± 3.7% (P < 0.0001) during the first half of the deployment. Leptin concentrations were significantly correlated with percentage body fat at each time point. The reduction in percentage body fat between Pre-deployment and Mid-deployment was 8.6%, with a corresponding 48% decrease in mean circulating leptin. Pre-deployment leptin and total and active ghrelin levels correlated with subsequent change in body mass; however. no changes were observed in the anorectic gut hormones GLP-1, PP, or PYY. CONCLUSIONS These data suggest that changes in appetite-regulating hormones in front line military personnel occur in response to, but do not drive, reductions in body mass.
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Affiliation(s)
- Neil E Hill
- Academic Department of Military Medicine, Royal Centre for Defence Medicine, Birmingham, UK; Section of Investigative Medicine, Imperial College London, London, UK
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280
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Bailey DP, Smith LR, Chrismas BC, Taylor L, Stensel DJ, Deighton K, Douglas JA, Kerr CJ. Appetite and gut hormone responses to moderate-intensity continuous exercise versus high-intensity interval exercise, in normoxic and hypoxic conditions. Appetite 2015; 89:237-45. [PMID: 25700630 DOI: 10.1016/j.appet.2015.02.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 02/04/2015] [Accepted: 02/13/2015] [Indexed: 02/04/2023]
Abstract
This study investigated the effects of continuous moderate-intensity exercise (MIE) and high-intensity interval exercise (HIIE) in combination with short exposure to hypoxia on appetite and plasma concentrations of acylated ghrelin, peptide YY (PYY), and glucagon-like peptide-1 (GLP-1). Twelve healthy males completed four, 2.6 h trials in a random order: (1) MIE-normoxia, (2) MIE-hypoxia, (3) HIIE-normoxia, and (4) HIIE-hypoxia. Exercise took place in an environmental chamber. During MIE, participants ran for 50 min at 70% of altitude-specific maximal oxygen uptake (V˙O2max) and during HIIE performed 6 × 3 min running at 90% V˙O2max interspersed with 6 × 3 min active recovery at 50% V˙O2max with a 7 min warm-up and cool-down at 70% V˙O2max (50 min total). In hypoxic trials, exercise was performed at a simulated altitude of 2980 m (14.5% O2). Exercise was completed after a standardised breakfast. A second meal standardised to 30% of participants' daily energy requirements was provided 45 min after exercise. Appetite was suppressed more in hypoxia than normoxia during exercise, post-exercise, and for the full 2.6 h trial period (linear mixed modelling, p <0.05). Plasma acylated ghrelin concentrations were lower in hypoxia than normoxia post-exercise and for the full 2.6 h trial period (p <0.05). PYY concentrations were higher in HIIE than MIE under hypoxic conditions during exercise (p = 0.042). No differences in GLP-1 were observed between conditions (p > 0.05). These findings demonstrate that short exposure to hypoxia causes suppressions in appetite and plasma acylated ghrelin concentrations. Furthermore, appetite responses to exercise do not appear to be influenced by exercise modality.
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Affiliation(s)
- Daniel P Bailey
- Institute for Sport and Physical Activity Research, Department of Sport Science and Physical Activity, University of Bedfordshire, Polhill Avenue, Bedford, Bedfordshire MK41 9EA, UK.
| | - Lindsey R Smith
- Institute for Sport and Physical Activity Research, Department of Sport Science and Physical Activity, University of Bedfordshire, Polhill Avenue, Bedford, Bedfordshire MK41 9EA, UK
| | - Bryna C Chrismas
- Institute for Sport and Physical Activity Research, Department of Sport Science and Physical Activity, University of Bedfordshire, Polhill Avenue, Bedford, Bedfordshire MK41 9EA, UK
| | - Lee Taylor
- Institute for Sport and Physical Activity Research, Department of Sport Science and Physical Activity, University of Bedfordshire, Polhill Avenue, Bedford, Bedfordshire MK41 9EA, UK
| | - David J Stensel
- School of Sport, Exercise and Health Sciences, Loughborough University, Ashby Road, Loughborough, Leicestershire LE11 3TU, UK
| | - Kevin Deighton
- School of Sport, Exercise and Health Sciences, Loughborough University, Ashby Road, Loughborough, Leicestershire LE11 3TU, UK
| | - Jessica A Douglas
- School of Sport, Exercise and Health Sciences, Loughborough University, Ashby Road, Loughborough, Leicestershire LE11 3TU, UK
| | - Catherine J Kerr
- Department of Sport and Health Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Oxford OX3 OBP, UK
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Gulec Suyen G, Isbil-Buyukcoskun N, Cam B, Ozluk K. Effects of centrally injected glucagon-like peptide-2 on gastric mucosal blood flow in rats: possible mechanisms. Peptides 2015; 64:62-6. [PMID: 25596156 DOI: 10.1016/j.peptides.2014.12.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 10/30/2014] [Accepted: 12/01/2014] [Indexed: 01/02/2023]
Abstract
"Glucagon-like peptide-2" (GLP-2) is a peptide that is released from the enteroendocrine L cells in response to food in the gastrointestinal tract. Peripheral injection of GLP-2 has been shown to increase gastrointestinal blood flow, but effects of central GLP-2 on any vascular bed has not been studied yet. The aim of this study is to investigate the effects of various doses of intracerebroventricularly (i.c.v.)-injected GLP-2 on gastric mucosal blood flow (GMBF) and contribution of calcitonin gene related peptide (CGRP), nitric oxide synthase-nitric oxide (NOS-NO) and cyclooxygenase-prostaglandin (COX-PG) systems to the possible effect. The gastric chamber technique was used to determine GMBF. Urethane anesthesia was used throughout the recording procedure. Male Wistar rats were treated with GLP-2 (100, 150 ve 200ng/10μl; i.c.v.) or saline (10μl; i.c.v.) in order to find out the effective dose of i.c.v. GLP-2 on GMBF. Then, CGRP receptor antagonist CGRP-(8-37) (10μg/kg; s.c.), NOS inhibitor NG-nitro-l-arginine methyl ester (l-NAME; 30mg/kg; s.c.) or COX inhibitor indomethacin (5mg/kg; i.p.) was injected before the effective dose of i.c.v. GLP-2. GMBF was measured continuously for 35min following GLP-2 and recorded every fifth minute. Non-parametric Kruskal-Wallis test was used for statistical analysis. Differences were considered to be significant at p<0.05. GMBF increased rapidly following 100ng GLP-2 injection and did not fall to the basal levels during 35min. Other doses of i.c.v. GLP-2 did not produce any significant difference in GMBF. CGRP receptor antagonist, CGRP-(8-37) (10μg/kg; s.c.) and COX inhibitor indomethacin (5mg/kg; i.p.) significantly prevented the increase in GMBF due to GLP-2 (100ng; i.c.v.), while l-NAME (30mg/kg; s.c.) was ineffective. None of the drugs produced a significant change in GMBF when administered alone. Thus we suggest that, i.c.v. GLP-2 increases GMBF and CGRP and endogenous prostaglandins but not NO, contribute to this effect.
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Affiliation(s)
- Guldal Gulec Suyen
- Acibadem University, School of Medicine, Department of Physiology, Istanbul, Turkey.
| | | | - Betul Cam
- Uludağ University, School of Medicine, Department of Physiology, Bursa, Turkey
| | - Kasim Ozluk
- Uludağ University, School of Medicine, Department of Physiology, Bursa, Turkey
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282
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Jurowich CF, Otto C, Rikkala PR, Wagner N, Vrhovac I, Sabolić I, Germer CT, Koepsell H. Ileal Interposition in Rats with Experimental Type 2 Like Diabetes Improves Glycemic Control Independently of Glucose Absorption. J Diabetes Res 2015; 2015:490365. [PMID: 26185767 PMCID: PMC4491588 DOI: 10.1155/2015/490365] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 06/05/2015] [Accepted: 06/07/2015] [Indexed: 02/08/2023] Open
Abstract
Bariatric operations in obese patients with type 2 diabetes often improve diabetes before weight loss is observed. In patients mainly Roux-en-Y-gastric bypass with partial stomach resection is performed. Duodenojejunal bypass (DJB) and ileal interposition (IIP) are employed in animal experiments. Due to increased glucose exposition of L-cells located in distal ileum, all bariatric surgery procedures lead to higher secretion of antidiabetic glucagon like peptide-1 (GLP-1) after glucose gavage. After DJB also downregulation of Na(+)-d-glucose cotransporter SGLT1 was observed. This suggested a direct contribution of decreased glucose absorption to the antidiabetic effect of bariatric surgery. To investigate whether glucose absorption is also decreased after IIP, we induced diabetes with decreased glucose tolerance and insulin sensitivity in male rats and investigated effects of IIP on diabetes and SGLT1. After IIP, we observed weight-independent improvement of glucose tolerance, increased insulin sensitivity, and increased plasma GLP-1 after glucose gavage. The interposed ileum was increased in diameter and showed increased length of villi, hyperplasia of the epithelial layer, and increased number of L-cells. The amount of SGLT1-mediated glucose uptake in interposed ileum was increased 2-fold reaching the same level as in jejunum. Thus, improvement of glycemic control by bariatric surgery does not require decreased glucose absorption.
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Affiliation(s)
- Christian Ferdinand Jurowich
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital of Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany
| | - Christoph Otto
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital of Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany
| | - Prashanth Reddy Rikkala
- Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstraße 6, 97070 Würzburg, Germany
| | - Nicole Wagner
- Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstraße 6, 97070 Würzburg, Germany
| | - Ivana Vrhovac
- Molecular Toxicology Unit, Institute for Medical Research & Occupational Health, Ksaverska Cesta 2, 10000 Zagreb, Croatia
| | - Ivan Sabolić
- Molecular Toxicology Unit, Institute for Medical Research & Occupational Health, Ksaverska Cesta 2, 10000 Zagreb, Croatia
| | - Christoph-Thomas Germer
- Department of General, Visceral, Vascular and Paediatric Surgery, University Hospital of Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany
| | - Hermann Koepsell
- Institute of Anatomy and Cell Biology, University of Würzburg, Koellikerstraße 6, 97070 Würzburg, Germany
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs-Institute, University of Würzburg, Julius-von-Sachs-Platz 2, 97082 Würzburg, Germany
- *Hermann Koepsell:
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283
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Abstract
In recent years, there has been a renewed interest in the role of dietary fibre in obesity management. Much of this interest stems from animal and human studies which suggest that an increased intake of fermentable fibre can suppress appetite and improve weight management. A growing number of reports have demonstrated that the principal products of colonic fermentation of dietary fibre, SCFA, contribute to energy homeostasis via effects on multiple cellular metabolic pathways and receptor-mediated mechanisms. In particular, over the past decade it has been identified that a widespread receptor system exists for SCFA. These G-protein-coupled receptors, free fatty acid receptor (FFAR) 2 and FFAR3 are expressed in numerous tissue sites, including the gut epithelium and adipose tissue. Investigations using FFAR2- or FFAR3-deficient animal models suggest that SCFA-mediated stimulation of these receptors enhances the release of the anorectic hormones peptide tyrosine tyrosine and glucagon-like peptide-1 from colonic L cells and leptin from adipocytes. In addition, the SCFA acetate has recently been shown to have a direct role in central appetite regulation. Furthermore, the SCFA propionate is a known precursor for hepatic glucose production, which has been reported to suppress feeding behaviour in ruminant studies through the stimulation of hepatic vagal afferents. The present review therefore proposes that an elevated colonic production of SCFA could stimulate numerous hormonal and neural signals at different organ and tissue sites that would cumulatively suppress short-term appetite and energy intake.
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284
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Zhang Y, Liu J, Yao J, Ji G, Qian L, Wang J, Zhang G, Tian J, Nie Y, Zhang YE, Gold MS, Liu Y. Obesity: pathophysiology and intervention. Nutrients 2014; 6:5153-83. [PMID: 25412152 PMCID: PMC4245585 DOI: 10.3390/nu6115153] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 07/21/2014] [Accepted: 10/29/2014] [Indexed: 01/09/2023] Open
Abstract
Obesity presents a major health hazard of the 21st century. It promotes co-morbid diseases such as heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Excessive energy intake, physical inactivity, and genetic susceptibility are main causal factors for obesity, while gene mutations, endocrine disorders, medication, or psychiatric illnesses may be underlying causes in some cases. The development and maintenance of obesity may involve central pathophysiological mechanisms such as impaired brain circuit regulation and neuroendocrine hormone dysfunction. Dieting and physical exercise offer the mainstays of obesity treatment, and anti-obesity drugs may be taken in conjunction to reduce appetite or fat absorption. Bariatric surgeries may be performed in overtly obese patients to lessen stomach volume and nutrient absorption, and induce faster satiety. This review provides a summary of literature on the pathophysiological studies of obesity and discusses relevant therapeutic strategies for managing obesity.
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Affiliation(s)
- Yi Zhang
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Ju Liu
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Jianliang Yao
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Gang Ji
- Xijing Gastrointestinal Hospital, the Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
| | - Long Qian
- Department of Biomedical Engineering, Peking University, Beijing 100871, China.
| | - Jing Wang
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Guansheng Zhang
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Jie Tian
- School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710071, China.
| | - Yongzhan Nie
- Xijing Gastrointestinal Hospital, the Fourth Military Medical University, Xi'an, Shaanxi 710032, China.
| | - Yi Edi Zhang
- Department of Psychiatry & McKnight Brain Institute, University of Florida, 1149 South Newell Drive, Gainesville, FL 32610, USA.
| | - Mark S Gold
- Department of Psychiatry & McKnight Brain Institute, University of Florida, 1149 South Newell Drive, Gainesville, FL 32610, USA.
| | - Yijun Liu
- Department of Psychiatry & McKnight Brain Institute, University of Florida, 1149 South Newell Drive, Gainesville, FL 32610, USA.
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285
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Bala V, Rajagopal S, Kumar DP, Nalli AD, Mahavadi S, Sanyal AJ, Grider JR, Murthy KS. Release of GLP-1 and PYY in response to the activation of G protein-coupled bile acid receptor TGR5 is mediated by Epac/PLC-ε pathway and modulated by endogenous H2S. Front Physiol 2014; 5:420. [PMID: 25404917 PMCID: PMC4217307 DOI: 10.3389/fphys.2014.00420] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 10/11/2014] [Indexed: 12/19/2022] Open
Abstract
Activation of plasma membrane TGR5 receptors in enteroendocrine cells by bile acids is known to regulate gastrointestinal secretion and motility and glucose homeostasis. The endocrine functions of the gut are modulated by microenvironment of the distal gut predominantly by sulfur-reducing bacteria of the microbiota that produce H2S. However, the mechanisms involved in the release of peptide hormones, GLP-1 and PYY in response to TGR5 activation by bile acids and the effect of H2S on bile acid-induced release of GLP-1 and PYY are unclear. In the present study, we have identified the signaling pathways activated by the bile acid receptor TGR5 to mediate GLP-1 and PYY release and the mechanism of inhibition of their release by H2S in enteroendocrine cells. The TGR5 ligand oleanolic acid (OA) stimulated Gαs and cAMP formation, and caused GLP-1 and PYY release. OA-induced cAMP formation and peptide release were blocked by TGR5 siRNA. OA also caused an increase in PI hydrolysis and intracellular Ca2+. Increase in PI hydrolysis was abolished in cells transfected with PLC-ε siRNA. 8-pCPT-2′-O-Me-cAMP, a selective activator of Epac, stimulated PI hydrolysis, and GLP-1 and PYY release. L-Cysteine, which activates endogenous H2S producing enzymes cystathionine-γ-lyase and cystathionine-β-synthase, and NaHS and GYY4137, which generate H2S, inhibited PI hydrolysis and GLP-1 and PYY release in response to OA or 8-pCPT-2′-O-Me-cAMP. Propargylglycine, an inhibitor of CSE, reversed the effect of L-cysteine on PI hydrolysis and GLP-1 and PYY release. We conclude: (i) activation of Gαs-coupled TGR5 receptors causes stimulation of PI hydrolysis, and release of GLP-1 and PYY via a PKA-independent, cAMP-dependent mechanism involving Epac/PLC-ε/Ca2+ pathway, and (ii) H2S has potent inhibitory effects on GLP-1 and PYY release in response to TGR5 activation, and the mechanism involves inhibition of PLC-ε/Ca2+ pathway.
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Affiliation(s)
- Vanitha Bala
- Gastroenterology Division, Department of Internal Medicine, Virginia Commonwealth University Richmond, VA, USA
| | - Senthilkumar Rajagopal
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
| | - Divya P Kumar
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
| | - Ancy D Nalli
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
| | - Sunila Mahavadi
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
| | - Arun J Sanyal
- Gastroenterology Division, Department of Internal Medicine, Virginia Commonwealth University Richmond, VA, USA
| | - John R Grider
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
| | - Karnam S Murthy
- Department of Physiology, VCU Program in Enteric Neuromuscular Sciences, Virginia Commonwealth University Richmond, VA, USA
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Arslan N, Sayin O, Tokgoz Y. Evaluation of serum xenin and ghrelin levels and their relationship with nonalcoholic fatty liver disease and insulin resistance in obese adolescents. J Endocrinol Invest 2014; 37:1091-7. [PMID: 25200997 DOI: 10.1007/s40618-014-0160-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 08/10/2014] [Indexed: 01/06/2023]
Abstract
AIM Xenin is a peptide of the neurotensin/xenopsin/xenin family secreted from gastric cells and other tissues. The first aim of this study was to investigate the serum xenin and ghrelin levels in obese children and compare the patients with healthy controls. The second aim was to compare the xenin levels in patients with nonalcoholic fatty liver disease (NAFLD) and also with insulin resistance with the patients without these complications. METHODS 62 obese adolescents (27 with NAFLD) and 32 healthy controls were enrolled in the study. Obesity was defined as a body mass index exceeding the 95th percentile for the patients' age and sex. NAFLD was diagnosed via ultrasonographic examination. The insulin resistance was calculated by a homeostasis model assessment (HOMA-IR) index. Serum xenin and ghrelin levels were assessed by enzyme-linked immunosorbent assay. RESULTS The mean serum xenin concentration was significantly higher in obese adolescents than the healthy peers (68.15 ± 0.63 vs 16.54 ± 0.07 pg/mL, p = 0.000). Serum xenin levels were not different between the patients with and without NAFLD and also between the patients with and without IR (p > 0.05). There was a positive correlation between xenin levels and relative weight (r = 0.663, p < 0.001) and HOMA-IR (r = 0.612, p < 0.001). Ghrelin was negatively correlated with relative weight (r = -0.283, p < 0.05). CONCLUSION In this study, serum xenin levels of both groups of obese patients were found higher than controls. On the other hand, xenin levels were not different in patients with and without NAFLD. High levels of xenin may be in relation with obesity.
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Affiliation(s)
- N Arslan
- Division of Pediatric Gastroenterology, Nutrition and Metabolism, Department of Pediatrics, Dokuz Eylul University Faculty of Medicine, Izmir, Turkey,
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287
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Dietary sugars: their detection by the gut-brain axis and their peripheral and central effects in health and diseases. Eur J Nutr 2014; 54:1-24. [PMID: 25296886 PMCID: PMC4303703 DOI: 10.1007/s00394-014-0776-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 09/24/2014] [Indexed: 12/25/2022]
Abstract
Background Substantial increases in dietary sugar intake together with the increasing prevalence of obesity worldwide, as well as the parallels found between sugar overconsumption and drug abuse, have motivated research on the adverse effects of sugars on health and eating behaviour. Given that the gut–brain axis depends on multiple interactions between peripheral and central signals, and because these signals are interdependent, it is crucial to have a holistic view about dietary sugar effects on health. Methods Recent data on the effects of dietary sugars (i.e. sucrose, glucose, and fructose) at both peripheral and central levels and their interactions will be critically discussed in order to improve our understanding of the effects of sugars on health and diseases. This will contribute to the development of more efficient strategies for the prevention and treatment for obesity and associated co-morbidities. Results This review highlights opposing effects of glucose and fructose on metabolism and eating behaviour. Peripheral glucose and fructose sensing may influence eating behaviour by sweet-tasting mechanisms in the mouth and gut, and by glucose-sensing mechanisms in the gut. Glucose may impact brain reward regions and eating behaviour directly by crossing the blood–brain barrier, and indirectly by peripheral neural input and by oral and intestinal sweet taste/sugar-sensing mechanisms, whereas those promoted by fructose orally ingested seem to rely only on these indirect mechanisms. Conclusions Given the discrepancies between studies regarding the metabolic effects of sugars, more studies using physiological experimental conditions and in animal models closer to humans are needed. Additional studies directly comparing the effects of sucrose, glucose, and fructose should be performed to elucidate possible differences between these sugars on the reward circuitry.
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288
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Sommer CA, Mostoslavsky G. RNA-Seq analysis of enteroendocrine cells reveals a role for FABP5 in the control of GIP secretion. Mol Endocrinol 2014; 28:1855-65. [PMID: 25268051 DOI: 10.1210/me.2014-1194] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
In response to fat intake, enteroendocrine K cells release the hormone glucose-dependent insulinotropic polypeptide (GIP). GIP acts on adipocytes to increase lipid uptake and enhance adipokine secretion, promoting weight gain and insulin resistance. Modulation of intestinal GIP release could therefore represent a therapeutic strategy for the treatment and prevention of obesity and diabetes. However, the prospects of using drugs to effectively target specific enteroendocrine cell types have been tempered by the realization that these cells share similar transcriptional programs and frequently employ common mechanisms of hormone secretion. To gain novel insights into the regulation of GIP release, we generated knock-in mice expressing green fluorescent protein (GFP) under the control of the endogenous GIP promoter that enable the isolation of a purified population of small intestine K cells. Using RNA sequencing, we comprehensively characterized the transcriptomes of GIP(GFP) cells as well as the entire enteroendocrine lineage derived from Neurogenin3-expressing progenitors. Among the genes differentially expressed in GIP(GFP) cells, we identified and validated fatty acid-binding protein 5 (FABP5) as a highly expressed marker of GIP-producing cells that is absent in other enteroendocrine cell types. FABP5 promotes intracellular transport and inactivation of endocannabinoids, including anandamide, which inhibits GIP release. Remarkably, we found that circulating levels of GIP were significantly decreased in FABP5-deficient mice in the fasting state and in response to acute, oral fat diet administration. Our findings highlight the power of RNA sequencing to uncover molecular signatures of specific enteroendocrine cell types that can potentially be exploited for therapeutic purposes in the treatment of metabolic disorders.
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Affiliation(s)
- Cesar A Sommer
- Section of Gastroenterology, Department of Medicine, and Center for Regenerative Medicine, Boston University School of Medicine, Boston, Massachusetts 02118
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289
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Burgio E, Lopomo A, Migliore L. Obesity and diabetes: from genetics to epigenetics. Mol Biol Rep 2014; 42:799-818. [DOI: 10.1007/s11033-014-3751-z] [Citation(s) in RCA: 122] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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290
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Lutz TA, Bueter M. The physiology underlying Roux-en-Y gastric bypass: a status report. Am J Physiol Regul Integr Comp Physiol 2014; 307:R1275-91. [PMID: 25253084 DOI: 10.1152/ajpregu.00185.2014] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Obesity and its related comorbidities can be detrimental for the affected individual and challenge public health systems worldwide. Currently, the only available treatment options leading to clinically significant and maintained body weight loss and reduction in obesity-related morbidity and mortality are based on surgical interventions. This review will focus on two main clinical effects of Roux-en-Y gastric bypass (RYGB), namely body weight loss and change in eating behavior. Animal experiments designed to understand the underlying physiological mechanisms of these post-gastric bypass effects will be discussed. Where appropriate, reference will also be made to vertical sleeve gastrectomy. While caloric malabsorption and mechanical restriction seem not to be major factors in this respect, alterations in gut hormone levels are invariably found after RYGB. However, their causal role in RYGB effects on eating and body weight has recently been challenged. Other potential factors contributing to the RYGB effects include increased bile acid concentrations and an altered composition of gut microbiota. RYGB is further associated with remarkable changes in preference for different dietary components, such as a decrease in the preference for high fat or sugar. It needs to be noted, however, that in many cases, the question about the necessity of these alterations for the success of bariatric surgery procedures remains unanswered.
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Affiliation(s)
- Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty University of Zurich, Zurich, Switzerland; Center of Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Institute of Laboratory Animal Science, University of Zurich, Zurich, Switzerland; and
| | - Marco Bueter
- Center of Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Department of Surgery, Division of Visceral and Transplantation Surgery, University Hospital Zurich, Zurich, Switzerland
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291
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292
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Pool AH, Kvello P, Mann K, Cheung SK, Gordon MD, Wang L, Scott K. Four GABAergic interneurons impose feeding restraint in Drosophila. Neuron 2014; 83:164-77. [PMID: 24991960 DOI: 10.1016/j.neuron.2014.05.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2014] [Indexed: 10/25/2022]
Abstract
Feeding is dynamically regulated by the palatability of the food source and the physiological needs of the animal. How consumption is controlled by external sensory cues and internal metabolic state remains under intense investigation. Here, we identify four GABAergic interneurons in the Drosophila brain that establish a central feeding threshold which is required to inhibit consumption. Inactivation of these cells results in indiscriminate and excessive intake of all compounds, independent of taste quality or nutritional state. Conversely, acute activation of these neurons suppresses consumption of water and nutrients. The output from these neurons is required to gate activity in motor neurons that control meal initiation and consumption. Thus, our study reveals a layer of inhibitory control in feeding circuits that is required to suppress a latent state of unrestricted and nonselective consumption.
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Affiliation(s)
- Allan-Hermann Pool
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Pal Kvello
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Kevin Mann
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Samantha K Cheung
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Michael D Gordon
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Liming Wang
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA
| | - Kristin Scott
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, 16 Barker Hall, Berkeley, CA 94720, USA.
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293
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Ghrelin promotes hepatic lipogenesis by activation of mTOR-PPARγ signaling pathway. Proc Natl Acad Sci U S A 2014; 111:13163-8. [PMID: 25157160 DOI: 10.1073/pnas.1411571111] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Although ghrelin has been demonstrated to stimulate energy intake and storage through a central mechanism, its effect on hepatic lipid metabolism remains largely uncharacterized. Ghrelin receptor antagonism or gene deletion significantly decreased obesity-associated hepatic steatosis by suppression of de novo lipogenesis, whereas exogenous ghrelin stimulated lipogenesis, leading to hepatic lipid accumulation in mice. The effects of ghrelin were mediated by direct activation of its receptor on hepatocytes. Cultured hepatocytes responded to ghrelin with increased lipid content and expression of lipogenesis-related genes. Ghrelin increased phosphorylation of S6, the downstream target of mammalian target of rapamycin (mTOR) signaling in cultured hepatocytes, whereas ghrelin receptor antagonism reduced hepatic phosphorylation of S6 in db/db mice. Inhibition of mTOR signaling by rapamycin markedly attenuated ghrelin-induced up-regulation of lipogenesis in hepatocytes, whereas activation of hepatic mTOR signaling by deletion of TSC1 increased hepatic lipogenesis. By interacting with peroxisome proliferator-activated receptor-γ (PPARγ), mTOR mediates the ghrelin-induced up-regulation of lipogenesis in hepatocytes. The stimulatory effect of ghrelin on hepatic lipogenesis was significantly attenuated by PPARγ antagonism in cultured hepatocytes and in PPARγ gene-deficient mice. Our study indicates that ghrelin activates its receptor on hepatocytes to promote lipogenesis via a mechanism involving the mTOR-PPARγ signaling pathway.
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294
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Mäde V, Bellmann-Sickert K, Kaiser A, Meiler J, Beck-Sickinger AG. Position and length of fatty acids strongly affect receptor selectivity pattern of human pancreatic polypeptide analogues. ChemMedChem 2014; 9:2463-74. [PMID: 25156249 DOI: 10.1002/cmdc.201402235] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Indexed: 12/25/2022]
Abstract
Pancreatic polypeptide (PP) is a satiety-inducing gut hormone targeting predominantly the Y4 receptor within the neuropeptide Y multiligand/multireceptor family. Palmitoylated PP-based ligands have already been reported to exert prolonged satiety-inducing effects in animal models. Here, we suggest that other lipidation sites and different fatty acid chain lengths may affect receptor selectivity and metabolic stability. Activity tests revealed significantly enhanced potency of long fatty acid conjugates on all four Y receptors with a preference of position 22 over 30 at Y1 , Y2 and Y5 receptors. Improved Y receptor selectivity was observed for two short fatty acid analogues. Moreover, [K(30)(E-Prop)]hPP2-36 (15) displayed enhanced stability in blood plasma and liver homogenates. Thus, short chain lipidation of hPP at key residue 30 is a promising approach for anti-obesity therapy because of maintained selectivity and a sixfold increased plasma half-life.
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Affiliation(s)
- Veronika Mäde
- Institute of Biochemistry, Faculty of Biosciences, Pharmacy and Psychology, Universität Leipzig, Brüderstraße 34, 04103 Leipzig (Germany), Fax: (+49) 341-97-36909
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295
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Sala PC, Torrinhas RS, Giannella-Neto D, Waitzberg DL. Relationship between gut hormones and glucose homeostasis after bariatric surgery. Diabetol Metab Syndr 2014; 6:87. [PMID: 25152774 PMCID: PMC4141947 DOI: 10.1186/1758-5996-6-87] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 08/06/2014] [Indexed: 12/18/2022] Open
Abstract
Type 2 diabetes mellitus (T2D) is emerging as a worldwide public health problem, and is mainly associated with an increased incidence of obesity. Bariatric surgery is currently considered the most effective treatment for severely obese patients. After bariatric surgery, T2D patients have shown a significant improvement in glycemic control, even before substantial weight loss and often discontinuation of medication for diabetes control. A central role for enteroendocrine cells from the epithelium of the gastrointestinal tract has been speculated in this postoperative phenomenon. These cells produce and secrete polypeptides - gut hormones - that are associated with regulating energy intake and glucose homeostasis through modulation of peripheral target organs, including the endocrine pancreas. This article reviews and discusses the biological actions of the gut hormones ghrelin, cholecystokinin, incretins, enteroglucagon, and Peptide YY, all of which were recently identified as potential candidates for mediators of glycemic control after bariatric surgery. In conclusion, current data reinforce the hypothesis that T2D reversion after bariatric surgery may be related to glycemic homeostasis developed by the intestine.
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Affiliation(s)
- Priscila Campos Sala
- />Medical School, Department of Gastroenterology, Digestive Surgery Discipline (LIM 35), University of São Paulo, Av. Dr. Arnaldo, 455, Cerqueira César, CEP: 01246-903, São Paulo, Brazil
| | - Raquel Susana Torrinhas
- />Medical School, Department of Gastroenterology, Digestive Surgery Discipline (LIM 35), University of São Paulo, Av. Dr. Arnaldo, 455, Cerqueira César, CEP: 01246-903, São Paulo, Brazil
| | | | - Dan Linetzky Waitzberg
- />Medical School, Department of Gastroenterology, Digestive Surgery Discipline (LIM 35), University of São Paulo, Av. Dr. Arnaldo, 455, Cerqueira César, CEP: 01246-903, São Paulo, Brazil
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296
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Psichas A, Sleeth ML, Murphy KG, Brooks L, Bewick GA, Hanyaloglu AC, Ghatei MA, Bloom SR, Frost G. The short chain fatty acid propionate stimulates GLP-1 and PYY secretion via free fatty acid receptor 2 in rodents. Int J Obes (Lond) 2014; 39:424-9. [PMID: 25109781 PMCID: PMC4356745 DOI: 10.1038/ijo.2014.153] [Citation(s) in RCA: 496] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 06/03/2014] [Accepted: 06/25/2014] [Indexed: 12/24/2022]
Abstract
Background and Objectives: The gut hormones peptide YY (PYY) and glucagon-like peptide 1 (GLP-1) acutely suppress appetite. The short chain fatty acid (SCFA) receptor, free fatty acid receptor 2 (FFA2) is present on colonic enteroendocrine L cells, and a role has been suggested for SCFAs in appetite regulation. Here, we characterise the in vitro and in vivo effects of colonic propionate on PYY and GLP-1 release in rodents, and investigate the role of FFA2 in mediating these effects using FFA2 knockout mice. Methods: We used Wistar rats, C57BL6 mice and free fatty acid receptor 2 knockout (FFA−/−) mice on a C57BL6 background to explore the impact of the SCFA propionate on PYY and GLP-1 release. Isolated colonic crypt cultures were used to assess the effects of propionate on gut hormone release in vitro. We subsequently developed an in vivo technique to assess gut hormone release into the portal vein following colonic infusion of propionate. Results: Propionate stimulated the secretion of both PYY and GLP-1 from wild-type primary murine colonic crypt cultures. This effect was significantly attenuated in cultures from FFA2−/− mice. Intra-colonic infusion of propionate elevated PYY and GLP-1 levels in jugular vein plasma in rats and in portal vein plasma in both rats and mice. However, propionate did not significantly stimulate gut hormone release in FFA2−/− mice. Conclusions: Intra-colonic administration of propionate stimulates the concurrent release of both GLP-1 and PYY in rats and mice. These data demonstrate that FFA2 deficiency impairs SCFA-induced gut hormone secretion both in vitro and in vivo.
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Affiliation(s)
- A Psichas
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - M L Sleeth
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - K G Murphy
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - L Brooks
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - G A Bewick
- 1] Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK [2] Division of Diabetes & Nutritional Sciences, Kings College London, Yeovil, UK
| | - A C Hanyaloglu
- Department of Surgery and Cancer, Institute of Reproductive and Developmental Biology, Imperial College, London, UK
| | - M A Ghatei
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - S R Bloom
- Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
| | - G Frost
- Nutrition and Dietetic Research Group, Section of Investigative Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College, London, UK
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297
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Yuan D, Wang T, Zhou C, Lin F, Chen H, Wu H, Wei R, Xin Z, Li Z. Leptin and cholecystokinin in Schizothorax prenanti: molecular cloning, tissue expression, and mRNA expression responses to periprandial changes and fasting. Gen Comp Endocrinol 2014; 204:13-24. [PMID: 24852347 DOI: 10.1016/j.ygcen.2014.05.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 05/06/2014] [Accepted: 05/08/2014] [Indexed: 12/15/2022]
Abstract
In the present study, full-length cDNA sequences of leptin and cholecystokinin (CCK) were cloned from Schizothorax prenanti (S. prenanti), and applied real-time quantitative PCR to characterize the tissue distribution, and appetite regulatory effects of leptin and CCK in S. prenanti. The S. prenanti leptin and CCK full-length cDNA sequences were 1121 bp and 776 bp in length, encoding the peptide of 171 and 123 amino acid residues, respectively. Tissue distribution analysis showed that leptin mRNA was mainly expressed in the liver of S. prenanti. CCK was widely expressed, with the highest levels of expression in the hypothalamus, myelencephalon, telencephalon and foregut of S. prenanti. The CCK mRNA expression was highly elevated after feeding, whereas the leptin mRNA expression was not affected by single meal. These results suggested that CCK is a postprandial satiety signal in S. prenanti, but leptin might not be. In present study, leptin and CCK gene expression were both decreased after fasting and increased after refeeding, which suggested leptin and CCK might be involved in regulation of appetite in S. prenanti. This study provides an essential groundwork to further elucidate the appetite regulatory systems of leptin and CCK in S. prenanti as well as in other teleosts.
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Affiliation(s)
- Dengyue Yuan
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Tao Wang
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Chaowei Zhou
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Fangjun Lin
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Hu Chen
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Hongwei Wu
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Rongbin Wei
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Zhiming Xin
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China
| | - Zhiqiong Li
- Department of Aquaculture, College of Animal Science and Technology, Sichuan Agricultural University, Ya'an, China.
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298
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Buhmann H, le Roux CW, Bueter M. The gut-brain axis in obesity. Best Pract Res Clin Gastroenterol 2014; 28:559-71. [PMID: 25194175 DOI: 10.1016/j.bpg.2014.07.003] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 06/11/2014] [Accepted: 07/05/2014] [Indexed: 01/31/2023]
Abstract
Currently the only effective treatment for morbid obesity with a proven mortality benefit is surgical intervention. The underlying mechanisms of these surgical techniques are unclear, but alterations in circulating gut hormone levels have been demonstrated to be at least one contributing factor. Gut hormones seem to communicate information from the gastrointestinal tract to the regulatory appetite centres within the central nervous system (CNS) via the so-called 'Gut-Brain-Axis'. Such information may be transferred to the CNS either via vagal or non-vagal afferent nerve signalling or directly via blood circulation. Complex neural networks, distributed throughout the forebrain and brainstem, are in control of feeding and energy homoeostasis. This article aims to review how appetite is potentially regulated by these gastrointestinal hormones. Identification of the underlying mechanisms of appetite and weight control may pave the way to develop better surgical techniques and new therapies in the future.
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Affiliation(s)
- Helena Buhmann
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Switzerland
| | - Carel W le Roux
- Diabetes Complications Research Centre, Conway Institute, School of Medicine and Medical Sciences, University College Dublin, Ireland; Gastrosurgical Laboratory, University of Gothenburg, Sweden
| | - Marco Bueter
- Department of Surgery, Division of Visceral and Transplantation Surgery, University Hospital Zurich, Zurich, Switzerland; Center of Integrative Human Physiology, University of Zurich, Zurich, Switzerland.
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299
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Mechanism of programmed obesity: altered central insulin sensitivity in growth-restricted juvenile female rats. J Dev Orig Health Dis 2014; 4:239-48. [PMID: 25054843 DOI: 10.1017/s2040174413000019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Intrauterine growth-restricted (IUGR) offspring are at increased risk of adult obesity, as a result of changes in energy balance mechanisms. We hypothesized that impairment of hypothalamic insulin signaling contributes to hyperphagia in IUGR offspring. Study pregnant dams were 50% food restricted from days 10 to 21 to create IUGR newborns. At 5 weeks of age, food intake was measured following intracerebroventricular (icv) injection of vehicle or insulin (10 mU) in control and IUGR pups. At 6 weeks of age, with pups in fed or fasted (48 h) states, pups received icv vehicle or insulin after which they were decapitated, and hypothalamic arcuate (ARC) nucleus dissected for RNA and protein expression. IUGR rats consumed more food than controls under basal conditions, consistent with upregulated ARC phospho AMP-activated protein kinase (pAMPK) and neuropeptide Y (NPY). Insulin acutely reduced food intake in both control and IUGR rats. Consistent with anorexigenic stimulation, central insulin decreased AMP-activated protein kinase and NPY mRNA expression and increased proopiomelanocortin mRNA expression and pAkt, with significantly reduced responses in IUGR as compared with controls. Despite feeding, IUGR offspring exhibit a persistent state of orexigenic stimulation in the ARC nucleus and relative resistance to the anorexigenic effects of icv insulin. These results suggest that impaired insulin signaling contributes to hyperphagia and obesity in IUGR offspring.
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300
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Guan X. The CNS glucagon-like peptide-2 receptor in the control of energy balance and glucose homeostasis. Am J Physiol Regul Integr Comp Physiol 2014; 307:R585-96. [PMID: 24990862 DOI: 10.1152/ajpregu.00096.2014] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The gut-brain axis plays a key role in the control of energy balance and glucose homeostasis. In response to luminal stimulation of macronutrients and microbiota-derived metabolites (secondary bile acids and short chain fatty acids), glucagon-like peptides (GLP-1 and -2) are cosecreted from endocrine L cells in the gut and coreleased from preproglucagonergic neurons in the brain stem. Glucagon-like peptides are proposed as key mediators for bariatric surgery-improved glycemic control and energy balance. Little is known about the GLP-2 receptor (Glp2r)-mediated physiological roles in the control of food intake and glucose homeostasis, yet Glp1r has been studied extensively. This review will highlight the physiological relevance of the central nervous system (CNS) Glp2r in the control of energy balance and glucose homeostasis and focuses on cellular mechanisms underlying the CNS Glp2r-mediated neural circuitry and intracellular PI3K signaling pathway. New evidence (obtained from Glp2r tissue-specific KO mice) indicates that the Glp2r in POMC neurons is essential for suppressing feeding behavior, gastrointestinal motility, and hepatic glucose production. Mice with Glp2r deletion selectively in POMC neurons exhibit hyperphagic behavior, accelerated gastric emptying, glucose intolerance, and hepatic insulin resistance. GLP-2 differentially modulates postsynaptic membrane excitability of hypothalamic POMC neurons in Glp2r- and PI3K-dependent manners. GLP-2 activates the PI3K-Akt-FoxO1 signaling pathway in POMC neurons by Glp2r-p85α interaction. Intracerebroventricular GLP-2 augments glucose tolerance, suppresses glucose production, and enhances insulin sensitivity, which require PI3K (p110α) activation in POMC neurons. Thus, the CNS Glp2r plays a physiological role in the control of food intake and glucose homeostasis. This review will also discuss key questions for future studies.
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Affiliation(s)
- Xinfu Guan
- U.S. Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics; and Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, Texas
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