Clinical trial NCT01891617: Exercise Effects on Insulin, Gut Peptides, and Appetite
Official title: The Exercise Effects on Appetite and Gut Peptides While on High-fat Diet
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Endocrine and Metabolic Responses to Exercise and Diets
Keywords: exercise
high carbohydrate and high fat diets
insulin
gut peptides
appetite
metabolism
glucose
Lead sponsor: University of Michigan
Sponsor class: OTHER
Collaborators: name: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
First posted: 2013-07-03
Enrollment: 16
Sex: FEMALE
Minimum age (years): 50
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Determine whether the mid-day suppression of hunger and amplified increase in the release of glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide 1 (GLP-1) following morning exercise is due to increased fat content of the diet per se or a combination of high fat diet after morning exercise. The action of gut peptides, particularly GLP-1, on gastric emptying is likely to be important in mediating its effects on postprandial appetite and glycemia (Nauck et al. 1997). Our hypothesis is that exercise amplifies gut peptide secretion when diet is enriched with fat, and that this stimulus suppresses the hunger sensation.

Detailed description: Specific aim: Determine whether a change in macronutrient composition from 60% carbohydrate and 25% fat to 30% carbohydrate and 45% fat is responsible by itself for suppression of hunger and increased secretory response of glucose-dependent insulinotropic hormone (GIP) and glucagon-like peptide-1 (GLP-1), or whether these changes depend on preceding exercise. We will measure (a) concentrations of plasma GIP and GLP-1 by chemiluminescent multiplex assay, (b) concentrations of plasma ancetaminophen to assess the gastric emptying rate, (c) concentrations of plasma insulin, and glucagon by radioimmunoassay, and glucose, ketone bodies, and free fatty acids with appropriate spectrophotometric methods, (d) hourly appetite responses with visual analog scale under two conditions: sedentary (SED) and exercise (EX).

Hypothesis: Hunger suppression and secretion of GIP and GLP-1 after the morning meal will be greater with slower gastric emptying rate when a meal consisting of 45% fat and 30% carbohydrate follows three hours after a 2-hour bout of moderate-intensity exercise than in the absence of exercise.

Eligibility criteria: Inclusion Criteria:

* Postmenopausal status
* Age 50 to 65 years
* BMI between 20 and 30 kg/m2.
* Good health status (normotensive, fasting glucose \< 100 mg/dl, , hematocrit \> 32%, hemoglobin \>12 mg/dl)
* Absence of restricted food intake
* Absence of endocrine and metabolic disorders requiring medication other than hormonally corrected hypothyroidism
* Absence of musculoskeletal disabilities that would prevent walking

Exclusion Criteria:

* Presence of endocrine and metabolic disease requiring medication, other than hormonally corrected hypothyroidism
* Presence of musculoskeletal disabilities that would prevent walking
* Smoking
* Active dieting
* Absence of listed inclusion criteria
* Unwillingness to follow study protocol.

Primary outcomes:
measure: Plasma insulin concentration
timeFrame: 36 hours
measure: Plasma glucagon concentration
timeFrame: 36 hours
measure: Plasma concentration of glucose-dependent insulinotropic peptide (GIP)
timeFrame: 36 hours
measure: Plasma concentration of free fatty acids
timeFrame: 36 hours
measure: Plasma concentration of beta-hydroxybutyrate
timeFrame: 36 hours
measure: Plasma glucose concentration
timeFrame: 36 hours
measure: daytime hourly appetite ratings
timeFrame: 36 hours
Secondary outcomes:
measure: Plasma concentrations of glucagon-like peptide-1 (GLP-1)
timeFrame: 36 hours
measure: Plasma concentrations of peptide tyrosine tyrosine (PYY)
timeFrame: 36 hours
Other outcomes:
Locations:
city: Ann Arbor
country: United States
facility: Michigan Clinical Research Unit
state: Michigan
Study officials:
affiliation: University of Michigan
name: Katarina Borer, PhD
role: PRINCIPAL_INVESTIGATOR
References: