PGC-1 and Mitochondrial Dysfunction in Diabetes

NCT ID: NCT01724515

Last Updated: 2014-05-12

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 16 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2012-09-30
• Study Completion Date: 2014-03-31

Brief Summary

The purpose of this study is determine if you have too much fat in your body that it will decrease the conversion of food energy into energy that your body can use.

Detailed Description

The investigators' prior research has focused on defining the changes in expression of nuclear encoded mitochondrial genes that predict changes in insulin sensitivity in skeletal muscle, with the goal of defining the molecular mechanisms underlying the connection between mitochondrial dysfunction and insulin resistance in skeletal muscle.

The purpose of this study is to determine whether experimental lipid oversupply decreases mitochondrial respiratory function. We will use mitochondrial respiration studies in vitro and mass spectrometry and proteomics analysis to test the hypothesis that experimental lipid oversupply:

1. Decreases mitochondrial respiration in response to lipid fuels.

2. Reduces abundance of mitochondrial proteins.

3. Alters phosphorylation of proteins in the electron transport chain.

Three groups of subjects will be studied: lean, healthy control subjects (n=12), obese non-diabetic subjects (n=12) and patients with type 2 Diabetes Mellitus (n=12) for a total of 36 subjects. Twenty subjects have completed the study at Arizona State University; the remaining 16 subjects will be accrued at the Mayo Clinic in Arizona.

Subjects will come to the Mayo Clinic 2 times. On study Day 1 subjects will be screened with a medical history and physical exam, and a 75 g oral glucose tolerance test, measure body fat percentage, and an electrocardiogram (EKG). On Study Day 2, subjects will report to the clinic after an overnight fast. Female subjects will take a urine pregnancy test. A muscle biopsy will be performed to take a small sample from one thigh. A lipid infusion will be performed for 5 hours (60 ml/hr), with blood samples taken at 8 intervals during the infusion. At the end of the 5 hour period, a second muscle biopsy will be taken from the other thigh. The fat infusion will stop, subjects will be given lunch and allowed to leave the clinic.

Conditions

Diabetes; Obese

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Obese Non-Diabetic Subjects

All subjects on this arm will undergo lipid infusion and muscle biopsies.

Group Type: EXPERIMENTAL

Lipid infusion and muscle biopsies

Intervention Type: OTHER

Subjects will undergo a baseline muscle biopsy, a lipid infusion for 5 hours (60 ml/hr), and a muscle biopsy after the lipid infusion.

Type 2 Diabetic Subjects

All subjects on this arm will undergo lipid infusion and muscle biopsies.

Group Type: EXPERIMENTAL

Lipid infusion and muscle biopsies

Intervention Type: OTHER

Subjects will undergo a baseline muscle biopsy, a lipid infusion for 5 hours (60 ml/hr), and a muscle biopsy after the lipid infusion.

Healthy Control Subjects

All subjects on this arm will undergo lipid infusion and muscle biopsies.

Group Type: EXPERIMENTAL

Lipid infusion and muscle biopsies

Intervention Type: OTHER

Subjects will undergo a baseline muscle biopsy, a lipid infusion for 5 hours (60 ml/hr), and a muscle biopsy after the lipid infusion.

Interventions

Lipid infusion and muscle biopsies

Subjects will undergo a baseline muscle biopsy, a lipid infusion for 5 hours (60 ml/hr), and a muscle biopsy after the lipid infusion.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

1. Subjects must be able to communicate meaningfully with the investigator and must be legally competent to provide written informed consent.

2. Subjects may be of either sex with age as described in each protocol. Female subjects must be non-lactating and will be eligible only if they have a negative pregnancy test throughout the study period.

3. Subjects must range in age as described in each specific protocol.

4. Subjects must have the following laboratory values:

1. Hematocrit ≥ 35 vol%

2. Serum creatinine ≤ 1.6 mg/dl

3. Aspartate Aminotransferase (AST) (SGOT) < 2 times upper limit of normal

4. Alanine Aminotransferase (ALT) (SGPT) < 2 times upper limit of normal

5. Alkaline phosphatase < 2 times upper limit of normal

6. Triglycerides < 150 mg/dl.

7. Prothrombin Time (PT) 11.7 - 14.3 seconds (during Intralipid/heparin infusion, PT will be determined to insure that it is < 1.5-2.0 times the normal value.)

8. Partial Thromboplastin Time (PTT) 23.0-37.0 seconds.

Exclusion Criteria

1. Subjects must not be receiving any of the following medications: thiazide or furosemide diuretics, beta-blockers, or other chronic medications with known adverse effects on glucose tolerance levels unless the patient has been on a stable dose of such agents for the past three months before entry into the study. Subjects may be taking a stable dose of estrogens or other hormonal replacement therapy, if the subject has been on these agents for the prior three months. Subjects taking systemic glucocorticoids are excluded.

2. Subjects with a history of clinically significant heart disease (New York Heart Classification greater than grade II; more than non-specific ST-T wave changes on the EKG), peripheral vascular disease (history of claudication), or pulmonary disease (dyspnea on exertion of one flight or less; abnormal breath sounds on auscultation) will not be studied.

3. Recent systemic or pulmonary embolus, untreated high-risk proliferative retinopathy, recent retinal hemorrhage, uncontrolled hypertension, systolic BP>180, diastolic BP>105, autonomic neuropathy, resting heart rate >100, electrolyte abnormalities.

• Minimum Eligible Age: 21 Years
• Maximum Eligible Age: 55 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

NIH

Sponsor Role: collaborator

Mayo Clinic

OTHER

Sponsor Role: lead

Responsible Party

Lawrence Mandarino

PI

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Lawrence Mandarino, Ph.D

Role: PRINCIPAL_INVESTIGATOR

Mayo Clinic

Locations

Mayo Clinic in Arizona

Scottsdale, Arizona, United States

Countries

United States

Other Identifiers

R01DK066483

Identifier Type: NIH

Identifier Source: secondary_id

View Link

11-006065 Aim 5

Identifier Type: -

Identifier Source: org_study_id