Effects of intragastric administration of L-tryptophan on appetite and gut hormone release in healthy, normal weight and obese subjects.

Not Applicable

Completed

• Conditions: Obesity; Type 2 Diabetes; Healthy Human Gastrointestinal Physiology; Diet and Nutrition - Obesity; Oral and Gastrointestinal - Normal oral and gastrointestinal development and function; Metabolic and Endocrine - Diabetes

• Registration Number: ACTRN12617001563358
• Lead Sponsor: Prof. Christine Feinle-Bisset

Brief Summary

Intragastric TRP has a potent energy intake-suppressant effect in both lean men and men with obesity, and is associated with sustained post-meal fullness and reductions in hunger, despite the substantially lower energy intake.

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2017-11-20
• Study Completion: 2019-10-30
• Last Update Posted: 24 February 2020

Recruitment & Eligibility

• Status: Completed
• Sex: Male
• Target Recruitment: 25

Inclusion Criteria

Healthy lean (BMI 19-25 kg/m2), and healthy obese (BMI 30-37 kg/m2), male subjects aged between 18 - 55 years, non-smoker, and without significant illness will be included in the study.

Exclusion Criteria

Significant gastrointestinal symptoms, disease or surgery;
Current gallbladder or pancreatic disease;
Cardiovascular or respiratory diseases;
Diagnosed type 2 diabetes;
Any other illnesses as assessed by the investigator (including chronic illnesses not explicitly listed above);
Use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may affect energy metabolism, gastrointestinal function, body weight or appetite (eg domperidone, cisapride, anticholinergic drugs (eg atropine), metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, Astragalus, St Johns Wort etc.);
Individuals with low ferritin (less than 30 ug/L) or iron (less than 8 umol/L) levels, or who have donated blood in the 12 weeks prior to taking part in the study;
Lactose intolerance/other food allergy(ies);
Vegetarians;
Current intake of greater than 2 standard drinks on greater than 5 days per week;
Current smokers of cigarettes/cigars/marijuana;
Current intake of any illicit substance;
High performance athletes;
Inability to comprehend study protocol;
Inability to tolerate naso-gastric tube;

Healthy subjects only:
Restrained eaters (score >12 on the three factor eating questionnaire).

Obese subjects only:
HbA1c <6.5%

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Energy intake at the buffet meal quantified using the computer software program FoodWorks.[A buffet meal will be presented during each study visit (t = 0-30). The subject will be allowed to freely consume food until comfortably full for 30 minutes.]