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Aliyu AI, Nixon A, Hoad CL, Marciani L, Corsetti M, Aithal GP, Cordon SM, Macdonald IA, Alhussain MH, Inoue H, Yamada M, Taylor MA. A comparative, randomised MRI study of the physiological and appetitive responses to gelling (alginate) and non-gelling nasogastric tube feeds in healthy men. Br J Nutr 2023; 130:1316-1328. [PMID: 36746392 PMCID: PMC10511685 DOI: 10.1017/s0007114523000302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/13/2023] [Accepted: 01/25/2023] [Indexed: 02/08/2023]
Abstract
Inclusion in nasogastric tube feeds (NGTF) of acid-sensitive, seaweed-derived alginate, expected to form a reversible gel in the stomach, may create a more normal intragastric state and modified gastrointestinal responses. This may ameliorate NGTF-associated risk of diarrhoea, upper gastrointestinal symptoms and appetite suppression. In a randomised, crossover, comparison study, undertaken in twelve healthy males, an alginate-containing feed (F + ALG) or one that was alginate-free (F-ALG) (300 ml) was given over 1 h with a 7-14-d washout period between treatments. Baseline and for 4-h post-feed initiation, MRI measurements were made to establish small bowel water content (SBWC), gastric contents volume (GCV) and appearance, and superior mesenteric artery blood flux. Blood glucose and gut peptides were measured. Subjective appetite and upper gastrointestinal symptoms scores were obtained. Ad libitum pasta consumption 3-h post-feeding was measured. F + ALG exhibited a gastric appearance consistent with gelling surrounded by a freely mobile water halo. Significant main effects of feed were seen for SBWC (P = 0·03) and peptide YY (PYY) (P = 0·004) which were attributed to generally higher values for SBWC with F + ALG (max difference between adjusted means 72 ml at 210 min) and generally lower values for PYY with F + ALG. GCV showed a faster reduction with F + ALG, less between-participant variation and a feed-by-time interaction (P = 0·04). Feed-by-time interactions were also seen with glucagon-like-peptide 1 (GLP-1) (P = 0·02) and glucose-dependent insulinotropic polypeptide (GIP) (P = 0·002), both showing a blunted response with F + ALG. Apparent intragastric gelling with F + ALG and subsequent differences in gastrointestinal and endocrine responses have been demonstrated between an alginate-containing and alginate-free feed.
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Affiliation(s)
- Abdulsalam I. Aliyu
- Department of Human Physiology, College of Medical Sciences, Gombe State University, Gombe, Nigeria
- The David Greenfield Human Physiology Unit, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
| | - Aline Nixon
- The David Greenfield Human Physiology Unit, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
| | - Caroline L. Hoad
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
| | - Luca Marciani
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
- Nottingham Digestive Diseases Centre, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, UK
| | - Maura Corsetti
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
- Nottingham Digestive Diseases Centre, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, UK
| | - Guruprasad P. Aithal
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
- Nottingham Digestive Diseases Centre, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, UK
| | - Sally M. Cordon
- The David Greenfield Human Physiology Unit, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
| | - Ian A. Macdonald
- The David Greenfield Human Physiology Unit, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
- Nestlé Institute of Health Sciences, Nestlé Research, Société des Produits Nestlé S.A, Lausanne, Switzerland
| | - Maha H. Alhussain
- Department of Food Science and Nutrition, King Saud University, Riyadh, Saudi Arabia
| | - Hiroaki Inoue
- Global Planning Group, Medical Solutions Vehicle, KANEKA CORPORATION, Osaka, Japan
| | - Masahiko Yamada
- Regenerative Medicine and Cell Therapy Laboratories, KANEKA CORPORATION, Kobe, Japan
| | - Moira A. Taylor
- The David Greenfield Human Physiology Unit, Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
- NIHR Nottingham Biomedical Research Centre at Nottingham University Hospitals NHS Trust and University of Nottingham, Nottingham, UK
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Camilleri M, Staiano A. Insights on Obesity in Children and Adults: Individualizing Management. Trends Endocrinol Metab 2019; 30:724-734. [PMID: 31395427 PMCID: PMC6779521 DOI: 10.1016/j.tem.2019.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/16/2019] [Accepted: 07/18/2019] [Indexed: 12/24/2022]
Abstract
For the management of obesity in childhood and adolescence, nonoperative approaches have limited efficacy, including community-based and behavioral interventions and pharmacotherapy approved for use in adults. Roux-en-Y gastric bypass (RYGB) and laparoscopic sleeve gastrectomy are efficacious in reducing weight, body mass index, and comorbidities in adolescents. Understanding the phenotype associated with obesity provides an opportunity to individualize patients' treatments directed at the brain-gut axis. These phenotypes include rapid gastric emptying, increased fasting gastric volume, reduced postprandial incretins, and central mechanisms that impact appetite and satiation including hedonic eating and affective disorders. Further studies are required in adolescents. Identifying phenotypes could enhance the efficacy of behavioral, dietary, and pharmacotherapeutic interventions alone or in combination in children and adolescents.
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Affiliation(s)
- Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research (CENTER), Mayo Clinic, Rochester, MN, USA.
| | - Annamaria Staiano
- Department of Translational Medical Science, Section of Pediatrics, University 'Federico II', Naples, Italy
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Mishra PK, Ekielski A, Mukherjee S, Sahu S, Chowdhury S, Mishra M, Talegaonkar S, Siddiqui L, Mishra H. Wood-Based Cellulose Nanofibrils: Haemocompatibility and Impact on the Development and Behaviour of Drosophila melanogaster. Biomolecules 2019; 9:biom9080363. [PMID: 31412664 PMCID: PMC6722666 DOI: 10.3390/biom9080363] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 08/02/2019] [Accepted: 08/06/2019] [Indexed: 02/06/2023] Open
Abstract
Wood-based cellulose nanofibrils (CNF) offer an excellent scaffold for drug-delivery formulation development. However, toxicity and haemocompatibility of the drug carrier is always an important issue. In this study, toxicity-related issues of CNF were addressed. Different doses of CNF were orally administered to Drosophila and different tests like the developmental cycle, trypan blue exclusion assay, larva crawling assay, thermal sensitivity assay, cold sensitivity assay, larval light preference test, climbing behaviour, nitroblue tetrazolium (NBT) reduction assay, adult phenotype, and adult weight were conducted to observe the impact on its development and behaviour. A haemocompatibility assay was done on the blood taken from healthy Wistar rats. In Drosophila, the abnormalities in larval development and behaviour were observed in the behavioural assays. However, the cytotoxic effect could not be confirmed by the gut staining and level of reactive oxygen species. The larvae developed into an adult without any abnormality in the phenotype. The CNF did cause loss of weight in the adult flies and did not cause much toxicity within the body since there was no phenotypic defect. Hemolysis data also suggested that CNF was safe at lower doses, as the data was well within acceptable limits. All these results suggest that cellulose nanofibres have no significant cytotoxic effects on Drosophila. However, the developmental and behavioural abnormalities suggest that CNF may act as a behavioural teratogen.
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Affiliation(s)
- Pawan Kumar Mishra
- Department of Wood Processing Technology, Mendel University in Brno, 61300 Brno, Czech Republic.
| | - Adam Ekielski
- Department of Production Management and Engineering, Warsaw University of Life Sciences, 02-787 Warsaw, Poland
| | - Sumit Mukherjee
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Technology, Rourkela, Odisha 76908, India
| | - Swetapadma Sahu
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Technology, Rourkela, Odisha 76908, India
| | - Saptarshi Chowdhury
- Biotechnology Department, Heritage Institute of Technology, Kolkata 700107, West Bengal, India
| | - Monalisa Mishra
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Technology, Rourkela, Odisha 76908, India
| | - Sushama Talegaonkar
- Department of Pharmaceutics, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi 110062, India
| | - Lubna Siddiqui
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, Govt. of NCT of Delhi 110017, New Delhi, India
| | - Harshita Mishra
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, Govt. of NCT of Delhi 110017, New Delhi, India
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Günter EA, Khramova DS, Markov PA, Popeyko OV, Melekhin AK, Beloserov VS, Martinson EA, Litvinets SG, Popov SV. Swelling behavior and satiating effect of the gel microparticles obtained from callus cultures pectins. Int J Biol Macromol 2019; 123:300-307. [DOI: 10.1016/j.ijbiomac.2018.11.081] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Revised: 09/11/2018] [Accepted: 11/12/2018] [Indexed: 10/27/2022]
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Keto Y, Hirata T, Takemoto Y, Yamano M, Yokoyama T. Influence of gastric acid on gastric emptying and gastric distension-induced pain response in rats--effects of famotidine and mosapride. Neurogastroenterol Motil 2012; 24:147-53, e88. [PMID: 22066725 DOI: 10.1111/j.1365-2982.2011.01809.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Gastroduodenal acidification has been reported to aggravate upper abdominal discomfort and pain that are symptoms suffered by functional dyspepsia (FD) patients. Delayed gastric emptying and hypersensitivity to gastric distension (GD) contribute importantly to the pathophysiology of FD. METHODS In the present study, we determined the influence of pentagastrin-stimulated endogenous gastric acid on gastric emptying and GD-induced pain responses using rat model systems. Moreover, we evaluated the effects of famotidine and mosapride on changes in gastric emptying and the GD-induced pain response to gastric acid hypersecretion. Gastric emptying was measured by excretion of glass beads that had been intragastrically administered with a liquid nutrient, and gastric pain response was evaluated by observing whether a GD-induced increase in mean blood pressure occurred. KEY RESULTS Pentagastrin (2 mg kg(-1), s.c.) which markedly and continuously stimulated gastric acid secretion, significantly delayed and enhanced respectively, gastric emptying and pain compared with saline-injected groups. Oral famotidine (0.1-3 mg kg(-1)) and mosapride (0.3-3 mg kg(-1)) administration in a dose-dependent manner accelerated the delay of gastric emptying. Furthermore, famotidine (0.3-3 mg kg(-1)) significantly alleviated the aggravation of the GD-induced pain response, but mosapride (10 mg kg(-1)) did not. CONCLUSIONS & INFERENCES We established rat models to evaluate the effect of gastric acid hypersecretion on gastric emptying and the GD-induced pain response. In these models, acid hypersecretion delayed gastric emptying and aggravated the pain response. Furthermore, we showed that famotidine ameliorated both delayed gastric emptying and gastric hypersensitivity, whereas mosapride only improved delayed gastric emptying.
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Affiliation(s)
- Y Keto
- Applied Pharmacology Research Laboratories, Drug Discovery Research, Astellas Pharma Inc., Tsukuba, Ibaraki, Japan.
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Van Kleef E, Van Trijp JCM, Van Den Borne JJGC, Zondervan C. Successful development of satiety enhancing food products: towards a multidisciplinary agenda of research challenges. Crit Rev Food Sci Nutr 2012; 52:611-28. [PMID: 22530713 PMCID: PMC3662086 DOI: 10.1080/10408398.2010.504901] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the context of increasing prevalence of overweight and obesity in societies worldwide, enhancing the satiating capacity of foods may help people control their energy intake and weight. This requires an integrated approach between various food-related disciplines. By structuring this approach around the new product development process, this paper aims to present the contours of such an integrative approach by going through the current state of the art around satiety enhancing foods. It portrays actual food choice as the end result of a complex interaction between internal satiety signals, other food benefits, and environmental cues. Three interrelated routes to satiating enhancement are to change the food composition to develop stronger physiological satiation and satiety signals, anticipate and build on smart external stimuli at the moment of purchase and consumption, and improve palatability and acceptance of satiety enhanced foods. Key research challenges in achieving these routes in the field of nutrition, food technology, consumer, marketing, and communication are outlined.
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Affiliation(s)
- E Van Kleef
- Wageningen University, Marketing & Consumer Behaviour Group, Wageningen, The Netherlands.
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Wanders AJ, van den Borne JJGC, de Graaf C, Hulshof T, Jonathan MC, Kristensen M, Mars M, Schols HA, Feskens EJM. Effects of dietary fibre on subjective appetite, energy intake and body weight: a systematic review of randomized controlled trials. Obes Rev 2011; 12:724-39. [PMID: 21676152 DOI: 10.1111/j.1467-789x.2011.00895.x] [Citation(s) in RCA: 137] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dietary fibres are believed to reduce subjective appetite, energy intake and body weight. However, different types of dietary fibre may affect these outcomes differently. The aim of this review was to systematically investigate the available literature on the relationship between dietary fibre types, appetite, acute and long-term energy intake, and body weight. Fibres were grouped according to chemical structure and physicochemical properties (viscosity, solubility and fermentability). Effect rates were calculated as the proportion of all fibre-control comparisons that reduced appetite (n = 58 comparisons), acute energy intake (n = 26), long-term energy intake (n = 38) or body weight (n = 66). For appetite, acute energy intake, long-term energy intake and body weight, there were clear differences in effect rates depending on chemical structure. Interestingly, fibres characterized as being more viscous (e.g. pectins, β-glucans and guar gum) reduced appetite more often than those less viscous fibres (59% vs. 14%), which also applied to acute energy intake (69% vs. 30%). Overall, effects on energy intake and body weight were relatively small, and distinct dose-response relationships were not observed. Short- and long-term effects of dietary fibres appear to differ and multiple mechanisms relating to their different physicochemical properties seem to interplay. This warrants further exploration.
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Affiliation(s)
- A J Wanders
- Division of Human Nutrition, Wageningen University, the Netherlands.
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Cameron KM, Speakman JR. Reduction of dietary energy density reduces body mass regain following energy restriction in female mice. J Nutr 2011; 141:182-8. [PMID: 21169228 DOI: 10.3945/jn.110.129056] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Restriction of energy intake induces a loss of body mass that is often regained when the restriction ends. We aimed to determine whether dietary energy density (independent of macronutrient composition) modulates postrestriction regain of body mass. Fifteen female mice consumed ad libitum a standard rodent diet (with 20% added cellulose). They were then subjected to a 20% energy restriction on this diet for 10 d. Following restriction, mice consumed ad libitum the same diet with either 0 or 40% added cellulose. The study utilized a crossover design so all mice consumed both diets. Body temperature, physical activity, and digestibility were all lower when consuming the 40% cellulose diet (P < 0.001). Mice regained less mass (9%) when consuming the 40% than the 0% cellulose diet, because net energy intake was reduced by 26% (P < 0.001), despite having a greater gross energy intake (P < 0.001) (29%). To test whether there might be a constraint on intake and digestibility of the 40% cellulose diet, 20 different female mice consumed this diet at room temperature and were then transferred to the cold (7°C) to determine whether they would increase intake of this diet in response to increased energy demands. It took up to 5 d after transfer for body mass, food intake, and digestibility to increase. This suggests a digestion constraint might have limited intake of the low-energy density diet immediately following restriction. Modulation of dietary energy density in the postrestriction phase may be a valuable strategy for maintaining mass loss achieved on energy-restricted diets.
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Affiliation(s)
- Kerry M Cameron
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, UK.
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Ström A, Melnikov SM, Boers HM, Mela DJ, Peters HPF. Odunsi et al. Results for CM3 cannot be extrapolated to alginates in general. Obesity (Silver Spring) 2010; 18:2069; author reply 2070. [PMID: 20978479 DOI: 10.1038/oby.2010.61] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Odunsi ST, Vázquez-Roque MI, Camilleri M, Papathanasopoulos A, Clark MM, Wodrich L, Lempke M, McKinzie S, Ryks M, Burton D, Zinsmeister AR. Effect of alginate on satiation, appetite, gastric function, and selected gut satiety hormones in overweight and obesity. Obesity (Silver Spring) 2010; 18:1579-84. [PMID: 19960001 PMCID: PMC2911486 DOI: 10.1038/oby.2009.421] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Lack of control of food intake, excess size, and frequency of meals are critical to the development of obesity. The stomach signals satiation postprandially and may play an important role in control of calorie intake. Sodium alginate (based on brown seaweed Laminaria digitata) is currently marketed as a weight loss supplement, but its effects on gastric motor functions and satiation are unknown. We evaluated effects of 10 days treatment with alginate or placebo on gastric functions, satiation, appetite, and gut hormones associated with satiety in overweight or obese adults. We conducted a randomized, 1:1, placebo-controlled, allocation-concealed study in 48 overweight or obese participants with excluded psychiatric comorbidity and binge eating disorder. All underwent measurements of gastric emptying (GE), fasting, and postprandial gastric volumes (GVs), postprandial satiation, calorie intake at a free choice meal and selected gut hormones after 1 week of alginate (three capsules vs. matching placebo per day, ingested 30 min before the main meal). Six capsules were ingested with water 30 min before the GE, GV, and satiation tests on days 8-10. There were no treatment group effects on GE or volumes, gut hormones (ghrelin, cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1), peptide YY (PYY)), satiation, total and macronutrient calorie intake at a free choice meal. There was no difference detected in results between obese and overweight patients. Alginate treatment for a period of 10 days showed no effect on gastric motor functions, satiation, appetite, or gut hormones. These results question the use of short-term alginate treatment for weight loss.
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Affiliation(s)
- Suwebatu T Odunsi
- Division of Biomedical Statistics and Bioinformatics, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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Papathanasopoulos A, Camilleri M. Dietary fiber supplements: effects in obesity and metabolic syndrome and relationship to gastrointestinal functions. Gastroenterology 2010; 138:65-72.e1-2. [PMID: 19931537 PMCID: PMC2903728 DOI: 10.1053/j.gastro.2009.11.045] [Citation(s) in RCA: 199] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Dietary fiber is a term that reflects a heterogeneous group of natural food sources, processed grains, and commercial supplements. Several forms of dietary fiber have been used as complementary or alternative agents in the management of manifestations of the metabolic syndrome, including obesity. Not surprisingly, there is a great variation in the biological efficacy of dietary fiber in the metabolic syndrome and body weight control. Diverse factors and mechanisms have been reported as mediators of the effects of dietary fiber on the metabolic syndrome and obesity. Among this array of mechanisms, the modulation of gastric sensorimotor influences appears to be crucial for the effects of dietary fiber but also quite variable. This report focuses on the role, mechanism of action, and benefits of different forms of fiber and supplements on obesity and the metabolic syndrome, glycemia, dyslipidemia, and cardiovascular risk and explores the effects of dietary fiber on gastric sensorimotor function and satiety in mediating these actions of dietary fiber.
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Berthold HK, Giesen TAH, Gouni-Berthold I. The stable isotope ketoisocaproic acid breath test as a measure of hepatic decarboxylation capacity: a quantitative analysis in normal subjects after oral and intravenous administration. Liver Int 2009; 29:1356-64. [PMID: 19555399 DOI: 10.1111/j.1478-3231.2009.02072.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND AIMS There is no generally accepted kinetic evaluation method for the stable isotope [(13)C]ketoisocaproic acid (KIC) breath test. Differences found in the results between women and men are contradictory. METHODS Oral and intravenous breath tests using 1 mg/kg stable isotope-labelled KIC were performed in healthy male and female volunteers. A power exponential function was fitted to the mass spectrometric data of breath (13)CO(2) enrichment, allowing mathematical analysis of time-to-peak-excretion, half-excretion time, percent label recovery and parameters describing the shape of the curve. Body composition was determined using bioelectrical impedance analysis. RESULTS After oral administration, total label recovery after 3 h was about 22% and was not different between men (n=7) and women (n=8). The time to maximal label excretion was 0.67 +/- 0.12 h in men and 0.9 +/- 0.32 h in women (P=0.028) and the excretion curve showed an initially slower rise in women compared with men. Adjusting for lean body mass or body water abrogated the sex differences. Total label recovery after intravenous administration was about 9%, suggesting that the substrate was rapidly catabolized in the muscle compartment after intravenous administration. CONCLUSIONS The modified power exponential function described allows standardized estimates of the KIC breath test results. When corrected for body composition, there are no differences in breath test results between men and women. The comparison between oral and intravenous results provides robust evidence that the KIC breath test measures predominantly hepatic and not muscle decarboxylation and is thus a highly specific liver function test.
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Affiliation(s)
- Heiner K Berthold
- Department of Clinical Pharmacology, University of Bonn, Bonn, Germany.
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