Blood Glucose, Appetite, Therapeutic Uses, Hormones
Conditions
Brief summary
The purpose of the study is to determine whether the sweet taste receptors in the gut are involved in sensing sweet substances and controlling appetite and the amount we eat. Lactisole is a substance commonly used in food products to reduce the perceived sweetness of certain sugars and sweeteners. The aim of this study is to investigate whether the responses to a glucose solution, intragastrically administered to healthy male and female volunteers, is affected by the presence of lactisole in the gut. Understanding the mechanisms by which nutrients are initially detected in the gut and how they influence food intake is critical to the development of novel food products that could reduce food consumption.
Detailed description
Obesity is epidemically prevalent and a major risk factor for chronic diseases making it fundamental to understand the pathways controlling food intake. During the course of a meal and afterwards the gut and brain communicate to control how full the eater feels and thus control the amount of food eaten. The information relayed from the gut to the brain regarding ingested nutrients is of increasing importance and understanding the mechanisms by which nutrient molecules are initially detected in the gut and how they signal to the brain to influence food intake is critical to the development of novel food products that could induce fullness and reduce food consumption. Increasing our understanding of how nutrients are sensed in the gut and how this may influence subsequent food intake provides promising targets for obesity prevention and treatment. Recent discoveries have shown that sweet taste receptors similar to those located in the tongue are present in the gut. It is suggested that theses receptors are involved in the way nutrients are sensed and may play an important role in appetite control and food intake.
Interventions
OTHERLactisole
A pre-infusion of lactisole solution (0.25mg/ml) is administered as a bolus (1ml/kg bodyweight)via intragastric tube. After 15 minutes a 1M glucose solution is administered as a bolus via intragastric tube.
Sponsors
University of Manchester
Northern Care Alliance NHS Foundation Trust
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* Aged between 18-45 years * BMI between 18-25kg/m2 * General good health
Exclusion criteria
* Underweight or Overweight (Body Mass Index \<19 or \>25 kg.m-2) * Females who are pregnant or breastfeeding * Currently taking medication (except females taking oral contraceptive) * Smokers * Currently dieting or have experienced a weight change +/- 3kg in past 6 months * Metabolic disorders (eg. Type 2 diabetes) * History of gastrointestinal disorders * Participation in other research in past 3 months
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Blood glucose | Blood samples will be collected at baseline and 5, 15 and 30 minute intervals until 150 minutes after the glucose infusion |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Subjective appetite ratings | 30 minute intervals | Participants will be asked to complete visual analogue scale questionnaire (VAS) up to a total of 6 times for the duration of each study |
| Gastric emptying rate | Breath samples are collected at 5, 15 and 30 minute intervals up to a total of 10 times until 150 minutes | In order to assess gastric emptying, a stable isotope of carbon, in the form of 13Csodium acetate will be added to the test meal. This is absorbed only once it has passed through the stomach into the duodenum. It is then metabolised and exhaled in the breath as 13Clabelled carbon dioxide (CO2) where it can be measured. |
| Energy intake | — | Energy intake will be assessed by an ad libitum test meal provided at the end of each study and food diaries completed for the remainder of the day |
| Gut hormones | Blood samples will be collected at baseline, 5, 15 and 30 minute intervals until 150 minutes after glucose infusion. | Blood samples will be processed to examine hormone levels of GLP-1, PYY, and insulin. |
Countries
United Kingdom
Outcome results
None listed