None listed
Conditions
Brief summary
The GI tract is the source of a large number of signals and mechanisms purported to be involved in the control of satiety, and which are generated by various types of mechanical or chemical stimuli. Mechanical stimulation is provided by distension of the luminal wall as foods transit the length of the gut, whilst chemical stimulation is provided by the nutrients entering the small and possibly also the large intestine. These stimuli then result in release of GI peptides and/or the activation of neural signals which may alter appetite-related sensations and eating behaviour. Secretion of GI peptides, when combined with neural signals from the stomach and small intestine generated by GI distension during and after meal ingestion, may lead to meal termination (=satiation) or may influence hunger and fullness between meals (=satiety). The ileum, or distal small intestine, has become the focus of recent studies which have hypothesised that stimulation of the ileum as a consequence of nutrient arrival may generate a range of satiety signals which enhance fullness, suppress hunger and decrease food intake. The mechanism by which this may occur has been termed the ‘Ileal Brake’. There are a range of feeding studies (Burns et al., 2000; Burns et al., 2001; Burns et al., 2002; Diepvens et al., 2007; Chan et al., 2010; Smit et al., 2010) which have shown appetite suppression in which the authours have attributed the effect to the delivery of nutrients to the ileum which in turn has stimulated the ileal brake. Studies conducted to date have focused on the delivery of dietary lipids, in particular lipid emulsions (Read et al., 1984a; Van Citters & Lin, 1999). Long-chain fatty acids are potent triggers of the ileal brake & several studies have demonstrated that the ileal brake may be activated by small amounts of fat or free fatty acids. The ileal brake has also been identified as a potentially important mechanism following delivery of CHO's.
Interventions
This is a gastrointestinal infusion study where a CHO load or saline control will be infused directly into the distal ileum and the proximal duodenum using an extended naso-gastric (NG) feeding tube (catheter). Introduction of an NG catheter is a commonly used clinical procedure in enterally fed patients.
The objective of this study is to determine whether direct infusion of dietary CHO into the distal small intestine (terminal ileum) alters appetite-related sensations and food intake in a gro
This is a gastrointestinal infusion study where a CHO load or saline control will be infused directly into the distal ileum and the proximal duodenum using an extended naso-gastric (NG) feeding tube (catheter). Introduction of an NG catheter is a commonly used clinical procedure in enterally fed patients. The objective of this study is to determine whether direct infusion of dietary CHO into the distal small intestine (terminal ileum) alters appetite-related sensations and food intake in a group of lean healthy men. The study aims to determine the effect of CHO infused into the ileum using a naso-ileal (NI) tube on: (i) subjective VAS-rated feelings of hunger, fullness and associated measures of satiety (ii) energy intake at a subsequent lunch and dinner meal (iii) gut peptides associated with satiety including cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) The primary hypotheses are: 1. Infusion of a CHO load into the ileum will increase satiety and decrease subsequent food intake when compared with a duodenal infusion 2. Infusion of a CHO load into the ileum will increase circulating levels of the appetite-related gut peptides CCK, GLP-1 and PYY. This is a 5 day residential study. Infusions: Four treatments comprising: 1. Saline control – infused into the duodenum 2. Glucose - infused into the duodenum 3. Saline control - infused into the ileum 4. Glucose - infused into the ileum The CHO dose will be a 15g bolus of glucose The infusions wil be administered over a duration of 1.5 hours. Participants will receive all 4 infusion treatments in a random order
Sponsors
Foundation for Science and Research (FRST)Ministry of Science Innovation
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
Male
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
Male Age 18-60 years Lean, as defined by BMI <25kg/m2 Healthy, as ascertained by self-report and blood test
Exclusion criteria
Overweight Any medical conditions or medications known to affect appetite -related parameters, including depression Low iron status, hence unsuitable for cannulation studies Participation in an active diet program and/or loss/gain of >10% body weight within the last 6 months Smoker or ex-smoker who quit within the last 6 months Hypersensitivities or allergies to any foods or ingredients included in the study Dislike and/or unwilling to consume items listed as study foods Unwilling/unable to comply with study protocol Participating in another clinical intervention trial
Outcome results
None listed