Dysfunction of Nutritive Blood Flow as a Determinant of Anabolic Resistance With Age; the Role of Amino Acids in Modulating Muscle Metabolism

Old Age (Focus; Not a Recognized Condition) Clinical Trial

— Ajinomoto1A  

Official title:

Dysfunction of Nutritive Blood Flow as a Determinant of Anabolic Resistance in Older People; The Role of Essential Amino Acids in Modulating Muscle Protein Metabolism; Bolus vs. Pulse Feeding Strategies and the Ability of Arginine to Rejuvenate Microvascular Responsiveness.

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT01735539
• Other study ID #: UNottingham F/3/2009
• Status: Active, not recruiting
• Phase: N/A
• First received: November 22, 2012
• Last updated: January 16, 2014
• Start date: December 2011
• Est. completion date: January 2014

Study information

• Verified date: January 2014
• Source: University of Nottingham
• Contact: n/a
• Is FDA regulated: No
• Health authority: UK: University of Nottingham Medical School Research Ethics CommitteeUK: University of Nottingham HTA Compliance Group
• Study type: Interventional

Clinical Trial Summary

The investigators plan to measure changes in muscle protein metabolism in response to feeding, comparing between a single large essential amino acid (EAA) feed (the normal building blocks of protein) and the provision of the same dose in 4 smaller feeds at 45min intervals. The investigators will perform this study in healthy older (65-75y) and younger (18-28) men. The investigators will also explore how feeding affects muscle blood flow as this is important in the delivery of the nutrients we eat to the muscle where they are used.

The investigators plan to supplement the feed with arginine, a safe and widely found non-essential amino acid, to explore if this can improve muscle blood flow.

Description:

We will provide a 15g mixed essential amino acid feed or 4 x 3.75g.

There is sexual dimorphism thus initially we will just recruit males. Powering calculations dictate n=8 in each group.

We will use well established stable isotope tracer techniques (with 13C6 Phenylalanine) to measure muscle protein synthesis and breakdown by Gas Chromatography - combustion - isotope ratio mass spectroscopy.

We will measure leg blood flow by phase shift Doppler and muscle microvascular flow by contrast enhanced ultrasound.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 40
• Est. completion date: January 2014
• Est. primary completion date: January 2014
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Male
• Age group: 18 Years to 75 Years

Eligibility

Inclusion Criteria:

• age 65-75 or 18-28

Exclusion Criteria:

• BMI >30

• Diabetes

• Beta blocker or steroid use

• Established cerebrovascular, peripheral vascular or ischaemic heart disease.

Study Design

Allocation: Non-Randomized, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Old Age (Focus; Not a Recognized Condition)

Intervention

Dietary Supplement:
• 15g EAA bolus
Oral; in aqueous solution
• 4 x 3.75g Mixed EAA Pulses
Oral; in aqueous solution
• 15g EAA Bolus supplemented with 3g Arginine
Oral; in aqueous solution

Locations

Country	Name	City	State
United Kingdom	University of Nottingham School of Graduate Entry Medicine and Health	Derby

Sponsors (1)

Lead Sponsor	Collaborator
University of Nottingham

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Muscle Protein Synthesis (FSR, fractional synthetic rate, %/hr)	We measure FSR when fasted and again 0-90, 90-180 and 180-240 post feed.	Across 6hr study	No
Secondary	Muscle Protein Breakdown (MPB)	MBP is measured during fasting and 0-90, 90-180 and 180-240mins post feed.	Across 6hr study	No
Secondary	Whole leg blood flow	We measure common femoral blood flow by doppler ultrasound when fasted and again 0-90, 90-180 and 180-240 post feed.	Across a 6hr study	No
Secondary	Muscle Microvascular Blood flow	We measure muscle microvascular flow using contrast enhanced ultrasound when fasted and again 0-90, 90-180 and 180-240 post feed.	Across a 6hr study	No