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

• Sponsor: University of Minnesota (Other)
• Overall Status: Completed
• CT.gov ID: NCT00786825
• Collaborator: (none)
• Enrollment: 10
• Location: 1
• Arms: 2
• Actual Duration (Months): 156
• Patients Per Site Per Month: 0.1

Study Details

Study Description

Brief Summary

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 or Disease	Intervention/Treatment	Phase
Type 1 Diabetes	Drug: somatostatin	Phase 2

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.

Study Design

• Study Type: Interventional
• Actual Enrollment: 10 participants
• Allocation: Non-Randomized
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Other
• Official Title: Measurement of Glucose/Glycogen Metabolism in Humans Using Magnetic Resonance at 4 or 7 Tesla
• Actual Study Start Date: Dec 1, 2004
• Actual Primary Completion Date: Dec 1, 2017
• Actual Study Completion Date: Dec 1, 2017

Arms and Interventions

Arm	Intervention/Treatment
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

Outcome Measures

Primary Outcome Measures

1. Brain Glycogen Turnover Rate [1 month]

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years to 65 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

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

Locations

	Site	City	State	Country	Postal Code
1	University of Minnesota	Minneapolis	Minnesota	United States	55414

Sponsors and Collaborators

• University of Minnesota

Investigators

• Principal Investigator: Elizabeth R Seaquist, MD, University of Minnesota

Study Documents (Full-Text)

• Informed Consent Form - Apr 8, 2014
• Study Protocol and Statistical Analysis Plan - Sep 30, 2011

More Information

Publications

None provided.

• Responsible Party: University of Minnesota
• ClinicalTrials.gov Identifier: NCT00786825
• Other Study ID Numbers: 9412M09040
• First Posted: Nov 6, 2008
• Last Update Posted: Dec 18, 2019
• Last Verified: Dec 1, 2019

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No
• Keywords provided by University of Minnesota: Type 1 diabetes; Hypoglycemia unawareness
• Additional relevant MeSH terms: Diabetes Mellitus, Type 1; Somatostatin

Study Results

Participant Flow

Arm/Group Title	Somatostatin	Healthy Controls
Arm/Group Description	Type 1 diabetes and Hypoglycemia unawareness somatostatin: Somatostatin may be used to suppress endogenous insulin secretion	Healthy control subjects
Period Title: Overall Study
STARTED	5	5
COMPLETED	5	5
NOT COMPLETED	0	0

Baseline Characteristics

Arm/Group Title	Somatostatin	Healthy Controls	Total
Arm/Group Description	Type 1 diabetes and Hypoglycemia unawareness somatostatin: Somatostatin may be used to suppress endogenous insulin secretion	Healthy control subjects	Total of all reporting groups
Overall Participants	5	5	10
Age (Count of Participants)
<=18 years	0 0%	0 0%	0 0%
Between 18 and 65 years	5 100%	5 100%	10 100%
>=65 years	0 0%	0 0%	0 0%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	57 (4)	57 (3)	57 (3)
Sex: Female, Male (Count of Participants)
Female	1 20%	1 20%	2 20%
Male	4 80%	4 80%	8 80%
Race (NIH/OMB) (Count of Participants)
American Indian or Alaska Native	0 0%	0 0%	0 0%
Asian	0 0%	0 0%	0 0%
Native Hawaiian or Other Pacific Islander	0 0%	0 0%	0 0%
Black or African American	0 0%	0 0%	0 0%
White	5 100%	5 100%	10 100%
More than one race	0 0%	0 0%	0 0%
Unknown or Not Reported	0 0%	0 0%	0 0%
Region of Enrollment (participants) [Number]
United States	5 100%	5 100%	10 100%

Outcome Measures

1. Primary Outcome

Title	Brain Glycogen Turnover Rate
Time Frame	1 month

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Somatostatin	Healthy Controls
Arm/Group Description	Type 1 diabetes and Hypoglycemia unawareness somatostatin: Somatostatin may be used to suppress endogenous insulin secretion	Healthy control subjects
Measure Participants	5	5
Mean (Standard Deviation) [mg/kg/min]	0.31 (0.23)	0.28 (0.06)

Adverse Events

Time Frame	Course of study, 1 month
Arm/Group Title	Somatostatin		Healthy Controls
Arm/Group Description	Type 1 diabetes and Hypoglycemia unawareness somatostatin: Somatostatin may be used to suppress endogenous insulin secretion		Healthy control subjects
All Cause Mortality
	Somatostatin		Healthy Controls
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/5 (0%)		0/5 (0%)
Serious Adverse Events
	Somatostatin		Healthy Controls
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/5 (0%)		0/5 (0%)
Other (Not Including Serious) Adverse Events
	Somatostatin		Healthy Controls
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/5 (0%)		0/5 (0%)

Limitations/Caveats

[Not Specified]

More Information

Certain Agreements

Principal Investigators are NOT employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.