Ignite Creation Date:
2024-05-05 @ 4:54 PM
Last Modification Date:
2024-10-26 @ 9:25 AM
Study NCT ID:
NCT00341406
Status:
COMPLETED
Last Update Posted:
2020-08-17
First Post:
2006-06-19
Brief Title:
Fat Cell Size in Insulin Resistance
Sponsor:
National Institute of Diabetes and Digestive and Kidney Diseases NIDDK
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Adipose Cell Size In Human Insulin Resistance
Status:
COMPLETED
Status Verified Date:
2020-08
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
This study conducted at Stanford University in Palo Alto California will examine how insulin metabolism and cardiovascular risk are altered in response to weight loss Insulin is a natural hormone that causes cells to remove glucose sugar from the blood People who are insulin-sensitive remove glucose efficiently People who are insulin-resistant require more insulin to remove glucose from the blood
Adult volunteers will be recruited for this study through advertisements in local newspapers in communities around Stanford University
Participants will undergo the following tests and procedures
Insulin sensitivity testing Before beginning the study participants will be tested for insulin sensitivity For the test two small catheters plastic tubes are placed into two veins - one for infusing glucose insulin and sandostatin a drug that blocks insulin secretion from the pancreas and one for drawing blood samples The infusions are done over 3 hours Blood samples are collected before during and at the end of the study to measure how well the cells remove glucose from the blood in response to insulin
Research diet Participants are assigned to a low-calorie diet tailored to the individuals metabolic rate The diets contain either 40 or 60 percent of total calories as carbohydrates 40 or 20 percent as fat and the rest as protein People with type 2 diabetes who are taking diabetes medicine with have a diet of 45 to 50 percent carbohydrates 35 to 40 percent fat and the rest protein
Meal profile Before beginning the diet and after 4 months on the diet participants are tested for the effects of the various study diets on control of blood sugar and fats On the day of each test participants have a physical examination and provide a medical history Then a small catheter is placed in a vein Blood samples are drawn before breakfast and then hourly for up to 8 hours
Participants who are diabetic are randomly assigned to take one of three diabetes medications - rosiglitazone glucophage or a sulfonylurea compound - to help control blood glucose levels
Magnetic resonance imaging This diagnostic test uses a strong magnetic field and radio waves to show structural and chemical changes in tissues During the scan the participant lies on a table in a narrow cylinder containing a magnetic field wearing ear plugs to muffle loud knocking and thumping sounds that occur during the scanning process He or she can speak with a staff member via an intercom system at all times during the procedure
In addition to these procedures patients may be asked to have a fat cell biopsy This is done to determine whether insulin-resistant people have fewer fat cells but more fat per cell than insulin-sensitive people For this test a small piece of fat tissue is surgically removed under local anesthetic from an area of the lower abdomen With the participants consent genetic testing may be done on the fat tissue sample to look for genes that may link central obesity to insulin resistance
Some participants may be asked to be followed for an additional 3 months after completion of the study for a continued weight loss program The follow-up includes weekly visits for weight measurements and a review of food records
Adult volunteers will be recruited for this study through advertisements in local newspapers in communities around Stanford University
Participants will undergo the following tests and procedures
Insulin sensitivity testing Before beginning the study participants will be tested for insulin sensitivity For the test two small catheters plastic tubes are placed into two veins - one for infusing glucose insulin and sandostatin a drug that blocks insulin secretion from the pancreas and one for drawing blood samples The infusions are done over 3 hours Blood samples are collected before during and at the end of the study to measure how well the cells remove glucose from the blood in response to insulin
Research diet Participants are assigned to a low-calorie diet tailored to the individuals metabolic rate The diets contain either 40 or 60 percent of total calories as carbohydrates 40 or 20 percent as fat and the rest as protein People with type 2 diabetes who are taking diabetes medicine with have a diet of 45 to 50 percent carbohydrates 35 to 40 percent fat and the rest protein
Meal profile Before beginning the diet and after 4 months on the diet participants are tested for the effects of the various study diets on control of blood sugar and fats On the day of each test participants have a physical examination and provide a medical history Then a small catheter is placed in a vein Blood samples are drawn before breakfast and then hourly for up to 8 hours
Participants who are diabetic are randomly assigned to take one of three diabetes medications - rosiglitazone glucophage or a sulfonylurea compound - to help control blood glucose levels
Magnetic resonance imaging This diagnostic test uses a strong magnetic field and radio waves to show structural and chemical changes in tissues During the scan the participant lies on a table in a narrow cylinder containing a magnetic field wearing ear plugs to muffle loud knocking and thumping sounds that occur during the scanning process He or she can speak with a staff member via an intercom system at all times during the procedure
In addition to these procedures patients may be asked to have a fat cell biopsy This is done to determine whether insulin-resistant people have fewer fat cells but more fat per cell than insulin-sensitive people For this test a small piece of fat tissue is surgically removed under local anesthetic from an area of the lower abdomen With the participants consent genetic testing may be done on the fat tissue sample to look for genes that may link central obesity to insulin resistance
Some participants may be asked to be followed for an additional 3 months after completion of the study for a continued weight loss program The follow-up includes weekly visits for weight measurements and a review of food records
Detailed Description:
Little is known about the turnover of adipose cells in the fat depots of normal animals and human subjects However microarray analysis of adipose cell gene expression in high risk insulin-resistant human subjects suggests that a reduced rate of adipose cell turnover is associated with enhanced adipose cell size and systemic insulin resistance New technology now permits a detailed analysis of adipose cell size including the detection of smaller cells which may be in the process of active differentiation We propose to examine the relationship between adipose cell size distribution and systemic insulin resistance in obese human subjects Adipose tissue biopsies will be obtained at Stanford University under protocols and consent forms approved by the Stanford University IRB Only procedures already being performed on subjects under these protocols will be used
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
None
Is a FDA Regulated Device?:
None
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 03-DK-N290 | None | None | None |