Pilot Study of Mitochondrial Biology in Human Platelets
Pilot Study of Mitochondrial Biology in Human Platelets
Type II diabetes mellitus is rapidly becoming a global pandemic with a deleterious impact on
 cardiovascular morbidity and mortality. Understanding its pathophysiology is important for
 the development of future therapeutic interventions. Emerging evidence suggests interplay
 between mitochondrial dysfunction and the development of insulin resistance. Interestingly,
 mitochondrial dysfunction in skeletal muscle and adipose tissue are early events in the
 development of type II diabetes mellitus and are proposed to play a role in exacerbating
 insulin resistance. Although it has been demonstrated that skeletal muscle of
 insulin-resistant individuals has reduced mitochondria and mitochondrial dysfunction, whether
 this disruption of mitochondrial function is more widespread has not been explored. We
 hypothesize that this disruption of mitochondrial function is more systemic and thereby may
 contribute to the development of peripheral insulin resistance and possibly promote the
 myriad of complications associated with diabetes.

 To test these assumptions, we propose an initial proof of concept study to evaluate
 mitochondrial biology in human platelets in normal volunteers, pre-diabetic and diabetic
 subjects to assess whether mitochondrial disruption/dysfunction evolves with the progression
 to type II diabetes. In parallel, proteomic analysis will be performed to evaluate whether
 the development of insulin resistance and diabetes confers a specific modulation in the
 biological signature of human platelets with disease progression. To delineate these
 concepts, we will evaluate study subject's glucose tolerance and insulin sensitivity and draw
 blood in parallel to study their platelets. Biological readouts will include: 1) the
 quantification of the mitochondrial proteome and electron transfer chain content; 2) the
 evaluation of platelet mitochondrial respiratory function and 3) to determine the
 mitochondrial reactive oxygen species capacity and defenses. If this hypothesis is validated,
 this study will show that the mitochondrial disruption/dysfunction is a more generalized
 finding in type II diabetes. Additionally, it would propose the use of platelets as potential
 biomarkers for early detection of mitochondrial function and assessment of disease. Finally,
 this would establish a peripheral blood readout of the modification of mitochondrial function
 as a novel approach to monitor the prevention and/or reversal of insulin resistance and
 diabetes in response to therapeutic strategies.
Type II diabetes mellitus is rapidly becoming a global pandemic with a deleterious impact on
 cardiovascular morbidity and mortality. Understanding its pathophysiology is important for
 the development of future therapeutic interventions. Emerging evidence suggests interplay
 between mitochondrial dysfunction and the development of insulin resistance. Interestingly,
 mitochondrial dysfunction in skeletal muscle and adipose tissue are early events in the
 development of type II diabetes mellitus and are proposed to play a role in exacerbating
 insulin resistance. Although it has been demonstrated that skeletal muscle of
 insulin-resistant individuals has reduced mitochondria and mitochondrial dysfunction, whether
 this disruption of mitochondrial function is more widespread has not been explored. We
 hypothesize that this disruption of mitochondrial function is more systemic and thereby may
 contribute to the development of peripheral insulin resistance and possibly promote the
 myriad of complications associated with diabetes.

 To test these assumptions, we propose an initial proof of concept study to evaluate
 mitochondrial biology in human platelets in normal volunteers, pre-diabetic and diabetic
 subjects to assess whether mitochondrial disruption/dysfunction evolves with the progression
 to type II diabetes. In parallel, proteomic analysis will be performed to evaluate whether
 the development of insulin resistance and diabetes confers a specific modulation in the
 biological signature of human platelets with disease progression. To delineate these
 concepts, we will evaluate study subject's glucose tolerance and insulin sensitivity and draw
 blood in parallel to study their platelets. Biological readouts will include: 1) the
 quantification of the mitochondrial proteome and electron transfer chain content; 2) the
 evaluation of platelet mitochondrial respiratory function and 3) to determine the
 mitochondrial reactive oxygen species capacity and defenses. If this hypothesis is validated,
 this study will show that the mitochondrial disruption/dysfunction is a more generalized
 finding in type II diabetes. Additionally, it would propose the use of platelets as potential
 biomarkers for early detection of mitochondrial function and assessment of disease. Finally,
 this would establish a peripheral blood readout of the modification of mitochondrial function
 as a novel approach to monitor the prevention and/or reversal of insulin resistance and
 diabetes in response to therapeutic strategies.
-  ELIGIBILITY CRITERIA:

 Inclusion Criteria (young control group):

 1. Adults older than 21 years and less than 40 years.

 2. Insulin sensitivity with a fasting glucose less than 100 mg/dl and a 2-hour post oral
 glucose tolerance test blood glucose less than 140 mg/dl.

 3. Subject understands protocol and provides written, informed consent.

 Inclusion Criteria (young insulin-resistant group):

 1. Adults older than 21 years and less than 40 years.

 2. Insulin resistance as defined by a fasting blood sugar of greater than or equal to
 100mg/dl but less than 125 mg/dl and/or a 2-hour post oral glucose tolerance test
 blood glucose greater than 140 mg/dl and less than 200 mg/dl.

 3. Subject understands protocol and provides written, informed consent.

 Inclusion Criteria (middle age control group):

 1. Adults greater than or equal to 40 years and less than or equal to 60 years.

 2. Insulin sensitivity with a fasting blood glucose less than 100 mg/dl and a 2-hour post
 oral glucose tolerance test blood glucose less than 140 mg/dl.

 3. Subject understands protocol and provides written, informed consent.

 Inclusion Criteria (middle age insulin-resistant group):

 1. Adults greater than or equal to 40 years and less than or equal to 60 years.

 2. Insulin resistance as defined by a fasting blood sugar of greater than or equal to
 100mg/dl but less than 125 mg/dl and/or a 2-hour post oral glucose tolerance test
 blood glucose greater than 140 mg/dl and less than 200 mg/dl.

 3. Subject understands protocol and provides written, informed consent.

 Inclusion Criteria (middle age type II diabetes group):

 1. Adults greater than or equal to 40 years and less than or equal to 60 years.

 2. Type II diabetes as defined by a fasting blood sugar of greater than 125 mg/dl and/or
 a 2-hour post oral glucose tolerance test blood glucose greater than 200 mg/dl if
 untreated and/or if subjects are on oral hypoglycemic agent therapy where the HbA1c is
 greater than 6.7 percent.

 3. Subject understands protocol and provides written, informed consent.

 Exclusion Criteria (all study subjects) :

 1. Uncontrolled hypertension, heart failure, unstable coronary artery disease or
 symptomatic peripheral arterial disease requiring changes in medication or medical
 intervention in the preceding 3 months.

 2. Insulin-dependant diabetes mellitus or current use of thiazolidinediones.

 3. Women of childbearing age unless recent pregnancy test is negative and are not breast
 feeding.

 4. Serum creatinine greater than 2.5 mg/dl.

 5. Liver transaminase levels greater than 2.5 times upper limit of normal.

 6. History of cancer treated with chemotherapy or irradiation in the last 5 years.

 7. Active inflammatory disease, or infection, or abnormal white blood cell differential.

 8. Enrollment in any drug studies within the last 30 days.

 9. BMI greater than 35 for the middle age groups and greater than 30 for the younger
 subjects.

 10. Age greater than 60 years.

 11. Another member of a potential study subject's immediate family has been
 recruited/participated in this study.

 12. The use of anticoagulation therapy, thiazide diuretics, corticosteroids, or some
 psychiatric drugs that cannot be stopped for medical reasons for a few days for study
 participation.