Muscle Perfusion and Protein Metabolism in Elderly

NCT00945256 | Completed Phase 1 Results

• 2 other identifiers: 03-213R01AG021539
• Study Type: interventional
• Target: 62
• Locations: 0 countries
• Sites: N/A

Brief Summary

The purpose of this study was to examine the role skeletal muscle perfusion plays in mediating muscle protein synthesis in healthy older and younger individuals. The investigators hypothesized that normalization of muscle perfusion in older men and women via exercise or infusion of a vasodilator would enhance nutritive flow and skeletal muscle protein synthesis in the elderly similar to that of their younger counterparts.

Conditions

Aging

Keywords

metabolism; exercise; sodium nitroprusside

Outcome Measures

Primary Outcomes (1)

• Mixed Muscle Fractional Synthesis Rate (FSR)

  The rate at which the body makes new muscle was assessed by determining the fractional synthesis rate (FSR). This technique determines how quickly new amino acids are used to make muscle. In this technique, a special (but natural and non-radioactive) version of an amino acid is infused into the blood. This special version of the amino acid is heavier than the most common version the same amino acid. This property allows it to be identified in a muscle sample. By determining how much of the special amino acid has accumulated over time in a muscle sample, the fractional synthesis rate can be determined. For example, if the rate were such that 1 of every 100 amino acids were of the special type after 1 day, the fractional synthesis rate would be 1% per day. In other words, 1/100 of the muscle would be newly made each day.

  Acute ( 8 hours)

Study Arms (5)

Young Aerobic Exercise

ACTIVE COMPARATOR

45 minutes of treadmill walking at 40% VO2 peak

Other: Aerobic Exercise

Elderly Aerobic Exercise

ACTIVE COMPARATOR

45 minutes of treadmill walking at 40% VO2 peak

Other: Aerobic Exercise

Young Sodium Nitroprusside

ACTIVE COMPARATOR

Sodium Nitroprusside given in a constant infusion for 180 minutes at a rate of 0.114 ug/kg/min

Drug: Sodium Nitroprusside

Elderly Sodium Nitoprusside

ACTIVE COMPARATOR

Sodium Nitroprusside given in a constant infusion for 180 minutes at a rate of 0.114 ug/kg/min

Drug: Sodium Nitroprusside

Elderly Sodium Nitroprusside and Amino Acid Drink

ACTIVE COMPARATOR

Sodium Nitroprusside given in a constant infusion for 180 minutes at a rate of 0.114 ug/kg/min and 7.5g amino acid drink taken orally

Drug: Sodium Nitroprusside; Dietary Supplement: Amino Acid Drink

Interventions

Aerobic Exercise OTHER

45 minuties of treadmill walking was completed at 40% VO2 peak

Elderly Aerobic Exercise; Young Aerobic Exercise

Sodium Nitroprusside DRUG

Sodium Nitroprusside was given in a constant infusion for 180 minutes at a rate of 0.114 ug/kg/min

Also known as: Nitropress

Elderly Sodium Nitoprusside; Elderly Sodium Nitroprusside and Amino Acid Drink; Young Sodium Nitroprusside

Amino Acid Drink DIETARY_SUPPLEMENT

7.5 gram Amino Acid drink

Elderly Sodium Nitroprusside and Amino Acid Drink

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age: young 18-40 yrs; elderly 60-85 yrs.
• Availability of transportation (i.e., subjects must be able to provide their own transportation to UTMB).
• Ability to sign informed consent (score \>24 on 30 item mini-mental status exam and no errors on assessment of judgment).

You may not qualify if:

• Patients with limiting or unstable angina or who demonstrate cardiac abnormalities such as \> 0.2 mV horizontal or downsloping ST segment depression, frequent arrhythmias (\>10 PVC/min), or valvular disease.
• Any patient with atrial fibrillation, history of syncope, angina, or congestive heart failure.
• Patients with vascular disease, as determined by the presence of risk factors of peripheral atherosclerosis (i.e., hypertension, obesity, uncontrolled diabetes, and evidence of venous or arterial insufficiency upon palpation of femoral, popliteal, and pedal arteries).
• Peripheral vascular disease as determined by history or abnormal ankle-brachial index by Doppler (\< 1.0).
• Any subject with blood pressure on three consecutive measurements taken at rest on separate occasions that has a systolic pressure \>170 mm Hg or a diastolic blood pressure \>100 mm Hg will be excluded. Subjects will not be included if they are taking blood pressure medication and have a blood pressure above these criteria.
• Any person HIV-seropositive, with active hepatitis, or any other immunosuppressive or autoimmune disease.
• Any patient taking beta blockers, vasodilators, angiotensin-converting enzyme inhibitors, calcium channel blockers, or alpha blockers.
• Any patient with uncontrolled metabolic diseases including any patient with liver or renal disease.
• Glucose intolerance: fasting plasma glucose concentration 110-126 mg/dL (6.1-7 mmol/L) and/or 2-h plasma glucose 140-200 mg/dL (7.8-11.1 mmol/L) during oral glucose tolerance test (OGTT).
• Currently in muscle strengthening program.
• Total knee replacement or moderate to severe degenerative joint disease of knees.
• Anemia (hemoglobin \<13 g/dL in males or \<12 g/dL in females).
• Any history of hypo- or hyper-coagulation disorders, including patients taking Coumadin or with a history of deep venous thrombosis (DVT) or pulmonary embolism (PE) at any point in their lifetimes.
• Currently taking aspirin and cannot stop for 7 days (i.e., medical indication for continued aspirin such as transient ischemic attacks).
• Presence of acute illness or metabolically unstable chronic illness.

Sponsors & Collaborators

• The University of Texas Medical Branch, Galveston: lead
• National Institute on Aging (NIA): collaborator

MeSH Terms

Conditions

Motor Activity

Interventions

Exercise; Nitroprusside

Condition Hierarchy (Ancestors)

Behavior

Intervention Hierarchy (Ancestors)

Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena; Ferricyanides; Cyanides; Anions; Ions; Electrolytes; Inorganic Chemicals; Ferric Compounds; Iron Compounds; Hydrogen Cyanide; Nitrogen Compounds

Results Point of Contact

• Title: Dr Melinda Sheffield-Moore, Professor of Medicine
• Organization: University of Texas Medical Branch

melmoore@utmb.edu

409-772-8707

Study Officials

• Melinda Sheffield-Moore, PhD

  UTMB

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: NONE
• Intervention Model: FACTORIAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 22, 2009
• First Posted: July 24, 2009
• Study Start: May 1, 2003
• Primary Completion: May 1, 2008
• Study Completion: May 1, 2009
• Last Updated: February 3, 2016
• Results First Posted: January 5, 2016

Record last verified: 2014-04