Measurement of Glucose/Glycogen Metabolism in Humans Using Magnetic Resonance at 4 or 7 Tesla

This study is currently recruiting participants. (see Contacts and Locations)
Verified May 2014 by University of Minnesota - Clinical and Translational Science Institute
Sponsor:
Information provided by (Responsible Party):
University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier:
NCT00786825
First received: November 5, 2008
Last updated: May 20, 2014
Last verified: May 2014
  Purpose

The long-range goal of this project is to determine the effects of diabetes and the hypoglycemic consequences of intensive therapy on in vivo brain glucose metabolism in humans. We will measure brain glycogen turnover and content in normal controls and subjects with diabetes under conditions of modest hyper-and hypoglycemia.


Condition Intervention
Type 1 Diabetes
Drug: somatostatin

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Official Title: Measurement of Glucose/Glycogen Metabolism in Humans Using Magnetic Resonance at 4 or 7 Tesla

Resource links provided by NLM:


Further study details as provided by University of Minnesota - Clinical and Translational Science Institute:

Primary Outcome Measures:
  • determine the effects of diabetes and the hypoglycemic consequences of intensive therapy on in vivo brain glucose metabolism [ Time Frame: 1 month ] [ Designated as safety issue: No ]

Estimated Enrollment: 15
Study Start Date: December 2004
Estimated Study Completion Date: June 2015
Estimated Primary Completion Date: June 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: somatostatin
Type 1 diabetes and Hypoglycemia unawareness
Drug: somatostatin
Somatostatin may be used to suppress endogenous insulin secretion
No Intervention: 2
Healthy control subjects

Detailed Description:

On the morning before the study subjects will report to the Clinical Research Center and will be asked to stay at the Clinical Research Center for up to 72 hours. You will be asked not to eat anything after midnight. Small plastic catheters will be placed in two veins in subjects arms for infusion of glucose and for measuring blood glucose levels every 15-30 minutes. While subjects are in the study they will continuously receive a small dose of glucose enriched with 13C label either through the catheter or by drinking a small amount of a sugar water solution every 15-60 minutes. Subjects will be asked to transfer to the Center for Magnetic Resonance Research every 6-8 hours (except at night) where they will be asked each time to conduct an MRI scan as follows: Subjects will be placed on the patient bed in the magnet room for one-to-two hours. A nurse will stay with the subject at all times during this study. During some of the scans subjects may be asked to perform a visual task such as watching a changing checkerboard pattern through a mirror placed in front of their eyes. After each scan subjects will receive a low carbohydrate meal for weight-maintenance.

Subjects may be asked to receive an infusion of glucose and/or insulin one-to-three times before and/or after the infusion of 13C-enriched glucose starts. During these infusions the subject's blood sugar will be maintained either higher or lower than normal levels for up to 3 hours. This will be done to assess the effect of hyper- or hypoglycemia on brain glycogen metabolism.

Subjects may also be asked several days prior to the study to report to the Clinical Research Center for a "mock" study to see if they are comfortable with the MRI scan and/or to test their body's response to either protocol (as described above, but carried out at the Clinical Research Center). If subjects would like to try the MRI procedure in advance, this test will not exceed 2 hours. If we need to test the subject's response to the infusion, this "pre-test" will involve only drawing blood and administering glucose and will be performed as described for either protocol above, but will last not more than 4 hours.

Magnetic resonance measurements will be performed in the magnet and are very similar to magnetic resonance imaging exams (MRI). Subjects will always have the possibility to signal when they feel claustrophobic and wish to be removed from the magnet. The magnetic resonance measurements will be associated with a regular clunking noise that subjects may initially find unpleasant. For their comfort they will be offered to wear ear plugs. During the measurements in the magnet subjects will be asked to lie still for most of the time.

  Eligibility

Ages Eligible for Study:   18 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Age 18-65
  • Healthy control
  • Must be able to provide informed consent
  • Type 1 diabetes with hypoglycemia unawareness with hemoglobin A1c < 7.5%
  • Poorly controlled diabetics with hemoglobin A1c > 7.5%
  • Subjects with hypoglycemia unawareness must report an inability to recognize at least some blood glucose values <58 mg/dL during the 3 months prior to the study.

Exclusion Criteria:

  • Over 300 pounds
  • Claustrophobic
  • History of ischemic heart disease, arrhythmia, of seizure disorder
  • Pregnant
  • On medications known to alter blood flow or carbohydrate metabolism
  • Have internally located pieces of metal
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00786825

Contacts
Contact: Anjali F Kumar, PA-C, MPAS 612-624-0470 kumar045@umn.edu
Contact: Elizabeth R Seaquist, MD 612-626-4833 seaqu001@umn.edu

Locations
United States, Minnesota
University of Minnesota Recruiting
Minneapolis, Minnesota, United States, 55414
Contact: Anjali F Kumar, PA-C    612-624-0470    kumar045@umn.edu   
Principal Investigator: Elizabeth R Seaquist, MD         
Sub-Investigator: Gulin Oz, PhD         
Sponsors and Collaborators
University of Minnesota - Clinical and Translational Science Institute
Investigators
Principal Investigator: Elizabeth R Seaquist, MD University of Minnesota - Clinical and Translational Science Institute
  More Information

No publications provided

Responsible Party: University of Minnesota - Clinical and Translational Science Institute
ClinicalTrials.gov Identifier: NCT00786825     History of Changes
Other Study ID Numbers: 9412M09040
Study First Received: November 5, 2008
Last Updated: May 20, 2014
Health Authority: United States: Food and Drug Administration

Keywords provided by University of Minnesota - Clinical and Translational Science Institute:
Type 1 diabetes
Hypoglycemia unawareness

Additional relevant MeSH terms:
Diabetes Mellitus
Diabetes Mellitus, Type 1
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Autoimmune Diseases
Immune System Diseases
Somatostatin
Hormones
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs
Pharmacologic Actions

ClinicalTrials.gov processed this record on September 11, 2014