AzTrials
AzTrials

ObesityPhase 1NCT00065377

Effects of Oral Glucosamine on Insulin and Blood Vessel Activity in Normal and Obese People

A Phase 1 study testing Glucosamine Hydrochloride in people with Obesity and Insulin Resistance, run by National Center for Complementary and Integrative Health (NCCIH) 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

This study will examine whether glucosamine affects the way the body responds to insulin. Insulin is a hormone that causes the body to use glucose (sugar). Insulin does not work as well in overweight people, causing a condition called insulin resistance. Read more about this study

Who is it for?
Ages 21 to 65 yearsHealthy volunteers can take part
Conditions the study is for
Obesity, Insulin Resistance
What is being tested?
Glucosamine Hydrochloride
How many people
60 participants
Where
1 siteUnited States
Study dates
Jul 2003to Jun 2006
Phase
Phase 1
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 21 to 65 years
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • HEALTHY VOLUNTEERS:
  • Males or females in good general health with no significant underlying illnesses, on no medication, between the ages of 21-65 years of age with HbA1C less than 6.5, fasting blood glucose less than 100 mg/dl, blood pressure less than 130/85, and BMI between 20-26 kg/m(2). Subjects should have never smoked tobacco or not smoked within the previous 2 years.
  • OBESE SUBJECTS:
  • Males or females in good general health with no significant underlying illnesses, on no medication, between the ages of 21-65 years of age with HbA1C less than 6.5, fasting blood glucose less than 110 mg/dl, blood pressure less than 130/85, and BMI between 30-40 kg/m(2).

Who cannot join

  • Subjects will be excluded if they have diabetes, hypertension, pregnancy, liver disease, pulmonary disease, renal insufficiency, coronary heart disease, heart failure, peripheral vascular disease, coagulopathy, actively smoking within last two years, in treatment for any form of cancer, positive tests for HIV, hepatitis B or C, or take systemic corticosteroids.
  • Subjects will also be excluded if they have an allergy to shellfish since glucosamine is derived from shellfish. Subjects will be excluded if they have taken glucosamine within the last three months. Subjects with allergies to blood products or eggs or known hypersensitivity to albumin will also be excluded from participating because of potential adverse effects from microbubble contrast agent. Subjects will be excluded from this study because children do not typically take glucosamine or have osteoarthritis.

Trial locations and contacts

1 site in 1 country.

United States1 site
  • National Center for Complementary and Alternative Medicine (NCCAM)

    Bethesda, Maryland, 20892

Other trials in United States

About this study

Official title: An Exploratory Study of the Effects of Oral Glucosamine Administration on Insulin Sensitivity and Capillary Recruitment in Normal and Obese Subjects

This study will examine whether glucosamine affects the way the body responds to insulin. Insulin is a hormone that causes the body to use glucose (sugar). Insulin does not work as well in overweight people, causing a condition called insulin resistance. Insulin also increases the flow of blood into muscle by opening inactive blood vessels. This study will test whether glucosamine, a nutritional supplement that many people take to treat arthritis, can cause or worsen insulin resistance or change how blood vessels react to insulin in normal weight and overweight people.

Healthy normal weight and overweight volunteers between 21 and 65 years of age may be eligible for this study. Candidates will be screened with a brief physical examination, medical history, and blood and urine tests. After screening, participants will have three additional outpatient clinic visits for the following procedures:

Read more

Visit 1

  • Glucose clamp test to measure the body's response to insulin: For this procedure, a needle is placed in a vein of each arm, one for drawing blood samples, and one for infusing glucose and a potassium solution. The glucose is infused continuously during this 4-hour test and blood is drawn frequently to monitor glucose and insulin levels. After the test, blood glucose levels are monitored for another 2 hours to make sure they remain at an adequate level to prevent hypoglycemia (low blood sugar).
  • Blood flow measurement: Blood flow in the brachial artery of the arm is measured to assess how many capillaries (very small blood vessels) are being used to supply nutrients and oxygen to the muscle in the forearm. This test is done at the same time as the glucose clamp test. Blood flow is measured using a technique called contrast ultrasound. A small amount of contrast agent consisting of gas-filled bubbles the size of red blood cells is infused over 10 minutes through one of the catheters placed in the vein for the glucose clamp test. The contrast agent is infused twice, once at the beginning of the glucose clamp test and once at the end of the test. The contrast material creates a signal in response to ultrasound that provides information about the distribution of capillaries in the forearm.
  • Assignment to medication group: Participants are randomly assigned to take either glucosamine or placebo three times a day by mouth for 6 weeks. At the end of the 6 weeks, no study drug is taken for 1 week, and then participants "cross-over" medications, those who took glucosamine for the first 6 weeks take placebo for the next 6 weeks and vice versa.

Visits 2 and 3

For these visits, the glucose clamp test and blood flow measurements are repeated. Visit 2 is scheduled at the end of the first 6-week treatment period, and Visit 3 is scheduled at the end of the second 6-week treatment period.

Read the detailed description

Glucosamine is a popular over-the-counter nutritional supplement that many people use for the treatment of osteoarthritis. Intravenous administration of glucosamine to animals or humans causes significant metabolic insulin resistance and vascular endothelial dysfunction. Moreover, experiments with various cell lines have implicated elevated glucosamine levels in the development of insulin resistance. However, there are no published studies examining the potential effects of oral glucosamine administration to modulate insulin sensitivity or capillary recruitment in humans. This is a significant concern because insulin resistance and vascular dysfunction contribute importantly to major public health problems including diabetes, obesity, hypertension, and cardiovascular diseases. Normal healthy volunteers and obese insulin resistant subjects will be enrolled in a randomized double-blind, placebo-controlled, crossover study to evaluate the effects of oral glucosamine to modulate insulin sensitivity and insulin-stimulated capillary recruitment. The reference standard hyperinsulinemic isoglycemic glucose clamp technique will be used to assess insulin sensitivity before treatment, after placebo or oral glucosamine (500 mg p.o. TID for 6 weeks), and after completion of the crossover. In addition, insulin-stimulated capillary recruitment will be measured at the same time as the glucose clamp studies by using the ultrasound microbubble contrast technique to assess blood flow in the brachial artery and capillary recruitment in forearm skeletal muscle in response to hyperinsulinemia. Finally, plasma glucosamine levels will be measured just prior to each glucose clamp study using an HPLC method. The results of this study will determine if oral glucosamine administration causes significant insulin resistance and impairment in insulin-stimulated capillary recruitment in healthy volunteers or worsens insulin resistance and capillary recruitment in obese subjects. In addition, our study will provide important information about how plasma glucosamine levels change with commonly used oral doses of glucosamine.

Being tested
Glucosamine Hydrochloride
Keywords
Diabetes, Insulin Resistance, Capillary Blood Flow, Osteoarthritis, Endothelial Dysfunction, Obesity, Healthy Volunteer, HV
Medical subject headings
Obesity, Insulin Resistance, Diabetes Mellitus, Osteoarthritis

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Glucosamine HydrochlorideDrug

Timeline

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

  1. First posted22 Jul 2003 (estimated)
  2. Study startJul 2003
  3. Study completionJun 2006

Resources

More details

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

Study design
Study type
Interventional
Phase
Phase 1
Primary purpose
Treatment
Enrolment
60 participants
IDs, dates and publications
ClinicalTrials.gov ID
NCT00065377
Sponsor's protocol ID
030251
Other IDs
03-AT-0251
Status last verified
Jun 2006
First submitted
21 Jul 2003
Last updated
26 Jun 2006
Results posted
No

Publications

  • Barclay TS, Tsourounis C, McCart GM. Glucosamine. Ann Pharmacother. 1998 May;32(5):574-9. doi: 10.1345/aph.17235.

    PubMed 9606479
  • Muniyappa R, Karne RJ, Hall G, Crandon SK, Bronstein JA, Ver MR, Hortin GL, Quon MJ. Oral glucosamine for 6 weeks at standard doses does not cause or worsen insulin resistance or endothelial dysfunction in lean or obese subjects. Diabetes. 2006 Nov;55(11):3142-50. doi: 10.2337/db06-0714.

    PubMed 17065354

Questions about this trial

What is this clinical trial studying?

A Phase 1 study testing Glucosamine Hydrochloride in people with Obesity and Insulin Resistance, run by National Center for Complementary and Integrative Health (NCCIH) 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 4 inclusion and 2 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 26 Jun 2006. 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.

What does this phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

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.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00065377, which also lists 2 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 26 Jun 2006.

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