AzTrials
AzTrials

DiabetesNCT00233298

A Study of the Function of Hormones Present In Taste Buds

An observational study of Diabetes and Obesity, run by National Institute on Aging (NIA) at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

The purpose of this study is to find out whether the hormones in the taste buds are affected by tasting and eating food, and also whether these hormone levels are affected by an increase in body weight or type 2 diabetes. Read more about this study

Who is it for?
Ages 12 to 50 yearsHealthy volunteers can take part
Conditions the study is for
Diabetes, Obesity, Pre-Diabetes
How many people
225 participants
Where
1 siteUnited States
Study dates
26 May 2005to 2 Jan 2015
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 12 to 50 years
  • All sexes
  • Healthy volunteers accepted
  • Child, Adult

Who may be able to join

  • Males or females age 20 to 50
  • body weight > 50 kg (110 pounds)
  • Group A
  • BMI < 25 kg/m(2)
  • healthy
  • Group B
Show all 24Show fewer
  • BMI greater than or equal to 30 kg/ m(2)
  • healthy
  • Group C
  • Pre-diabetes
  • Pre-diabetes is defined as having either impaired fasting glucose (IFG) (fasting plasma glucose (FPG) greater than or equal to100 mg/dl but < 126 mg/dl) and/or impaired glucose tolerance (IGT) (2-hour OGTT glucose greater than or equal to140 mg/dl but < 200 mg/dl).
  • BMI greater than or equal to 30 kg/m(2)
  • Group D
  • Type 2 diabetes (on diet or oral agents management only except for thiazolidinediones)
  • Type 2 diabetes is defined as FPG 126 mg/dl and/or 2-hour OGTT glucose
  • 200
  • BMI greater than or equal to 30 kg/m(2)
  • Screening laboratory evaluations with no significant abnormal results:
  • comprehensive metabolic panel
  • complete blood count with differential and platelets
  • fasting plasma glucose < 100 mg/dl for healthy groups only (Group A and B)
  • 2-hour 75-gram OGTT glucose < 140 mg/dl for healthy groups only (Group A and B)
  • Negative pregnancy test for women of child-bearing potential
  • Able to complete an informed consent

Who cannot join

  • Pregnancy (pregnancy has been shown to be associated with decrease in insulin sensitivity
  • Group A and B subjects cannot have FPG greater than or equal to 100 mg/dl or 2-hr OGTT greater than or equal to 140 mg/dl
  • Group D subjects cannot have FPG > 240 mg/dl during the screening visit
  • Group D subjects cannot have their morning fasting finger-stick glucose > 240 mg/dl during the 5 days (3 days for glucophage) prior to the visit when their oral hypoglycemic agent(s) are discontinued
  • Subjects with type 2 diabetes on insulin therapy
  • Hematocrit < 36% for women and < 38% for men
Show all 12Show fewer
  • Peanut allergy
  • Presence of other medical conditions that could affect glucose homeostasis
  • Use of medications known to impair glucose homeostasis (i.e., amiloride shown to inhibit certain taste responses in hamsters)
  • History of liver or renal disease
  • History of gastrointestinal or endocrine disorders except for treated hypo- or hyperthyroidism
  • Long-term glucocorticoid use (over one month), or other immunosuppressive agents within the past 5 years

Trial locations and contacts

1 site in 1 country.

United States1 site

  • National Institute of Aging, Clinical Research Unit

    Baltimore, Maryland, 21224

Other trials in United States

About this study

The purpose of this study is to find out whether the hormones in the taste buds are affected by tasting and eating food, and also whether these hormone levels are affected by an increase in body weight or type 2 diabetes.

Read the detailed description

Cephalic phase of insulin secretion is regulated by autonomic and endocrine responses to food-related sensory stimulation such as sight, smell, and taste. Human taste perception comprises of at least five distinct qualities: bitterness, saltiness, sourness, sweetness, and umami, the sensation elicited by glutamate, commonly found in protein (meat, fish, and legumes) and flavor enhancer such as monosodium glutamate (MSG).

Both the sweet and umami taste stimuli had been shown to illicit cephalic-phase insulin release in rats. Oral sensory stimulation in human with modified sham feeding (MSF where food is smelled, chewed, but not swallowed) had been shown to enhance insulin release during the cephalic phase, lower postprandial glucose level, and improve glucose tolerance in healthy subjects. The loss of pre-absorptive insulin response has been shown to impair glucose tolerance. Furthermore, patients with type 2 diabetes and their first degree relatives had been shown to have impairment of sweet taste.

Recently, glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) have been found in the taste cells located in the taste buds of mice (unpublished data). These new findings raise several interesting questions of whether strict tasting of food without ingestion may stimulate secretion of GLP-1 and PYY from the taste cells, whether their secretion is involved in the afferent input of the cranial nerves, and whether this secretion is impaired in obesity and in patients with pre-diabetes or type 2 diabetes. We also want to investigate whether different tastants, such as sweet versus umami, and different food contents such as percent fat versus carbohydrate compositions, would elicit different hormonal responses.

Keywords
Hypoglycemia, Blood Sugar, Blood Glucose Level, Insulin Sensitivity, Metabolism, Type 2 Diabetes, Healthy
Medical subject headings
Diabetes Mellitus, Obesity, Glucose Intolerance, Metabolic Syndrome, Hypoglycemia, Insulin Resistance, Diabetes Mellitus, Type 2

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Whether CLP-1 and PYY are involved in the cephalic phase response during feeding

    Measured: 12 months

  2. Differences in response among healthy, healthy obese, pre-diabetic or 3 diabetes

    Measured: 12 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted5 Oct 2005 (estimated)
  2. Study start26 May 2005
  3. Study completion2 Jan 2015

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Time perspective
Prospective
Enrolment
225 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT00233298
Sponsor's protocol ID
999905254
Other IDs
05-AG-N254
Status last verified
2 Jan 2015
First submitted
3 Oct 2005
Last updated
5 Apr 2018
Results posted
No

Publications

  • Ahren B. Autonomic regulation of islet hormone secretion--implications for health and disease. Diabetologia. 2000 Apr;43(4):393-410. doi: 10.1007/s001250051322.

    PubMed 10819232

  • Lindemann B. Taste reception. Physiol Rev. 1996 Jul;76(3):719-66. doi: 10.1152/physrev.1996.76.3.719.

    PubMed 8757787

  • Niijima A, Togiyama T, Adachi A. Cephalic-phase insulin release induced by taste stimulus of monosodium glutamate (umami taste). Physiol Behav. 1990 Dec;48(6):905-8. doi: 10.1016/0031-9384(90)90247-2.

    PubMed 2087524

Questions about this trial

What is this clinical trial studying?

An observational study of Diabetes and Obesity, run by National Institute on Aging (NIA) at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 24 inclusion and 12 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 5 Apr 2018. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Whether CLP-1 and PYY are involved in the cephalic phase response during feeding (time frame: 12 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00233298, which also lists 3 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 5 Apr 2018.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in