Modulation of Muscle Protein Metabolism by Essential Amino Acids
- Conditions
- Old Age
- Interventions
- Dietary Supplement: 15g Mixed Essential Amino AcidsDietary Supplement: 3g LeucineDietary Supplement: 15g Mixed Essential Amino Acid REFEED
- Registration Number
- NCT01890369
- Lead Sponsor
- University of Nottingham
- Brief Summary
The investigators plan to explore the ability of amino acids, the building blocks of proteins in our bodies and in the food we eat, to stimulate muscles to grow and stay strong. The investigators will investigate how rapidly after one meal the human body is ready to make use of a second meal and look at the molecular mechanisms underlying this. The investigators will look at these phenomena in older men as this group is known to be subject to a gradual loss of muscle mass and strength.
- Detailed Description
Muscles can stay very constant in size for much of adult life yet dramatic wasting is seen in advanced age and ill health. A better understanding of how muscles regulate their size will help design treatments to slow wasting in disease and to promote active aging. We plan to study a group of older men, \~70yrs, the age at which muscle bulk starts to decrease, to observe how the muscles respond to feeding. We will provide a drink that contains the digested products of proteins from which muscles are built. Taking blood samples and some tiny biopsies of muscle (done under local anaesthesia) will allow us to measure muscle turnover and we will be able to measure for how long after a meal muscles actively take in nutrients before becoming "full". We will also measure how long the muscle remains "full" before it returns to a state where it can again be stimulated to take in nutrients. We will also explore if leucine, one of the component parts of protein (especially in meat and dairy products) and a food widely used supplement, can promote the early re-stimulation of muscle by eating.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- Male
- Target Recruitment
- 32
- Male
- 65-75yrs
- BMI 18-28
- Type 2 Diabetes mellitus
- Neurological Disease
- Significant cardiac, hepatic or renal disease
- Active malignancy
- Medication inc. Corticosteroids, NSAID use, Beta adrenoblockers.
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Early leucine refeed 15g Mixed Essential Amino Acids 15g Mixed Essential Amino Acids. 90 min delay. 3g Leucine Early leucine refeed 3g Leucine 15g Mixed Essential Amino Acids. 90 min delay. 3g Leucine Early EAA refeed 15g Mixed Essential Amino Acids 15g Mixed Essential Amino Acids. 90 min delay. 15g Mixed Essential Amino Acid REFEED Early EAA refeed 15g Mixed Essential Amino Acid REFEED 15g Mixed Essential Amino Acids. 90 min delay. 15g Mixed Essential Amino Acid REFEED Mid latency EAA refeed 15g Mixed Essential Amino Acids 15g Mixed Essential Amino Acids. 150 min delay. 15g Mixed Essential Amino Acid REFEED Mid latency EAA refeed 15g Mixed Essential Amino Acid REFEED 15g Mixed Essential Amino Acids. 150 min delay. 15g Mixed Essential Amino Acid REFEED Late latency EAA refeed 15g Mixed Essential Amino Acids 15g Mixed Essential Amino Acids. 210 min delay. 15g Mixed Essential Amino Acid REFEED Late latency EAA refeed 15g Mixed Essential Amino Acid REFEED 15g Mixed Essential Amino Acids. 210 min delay. 15g Mixed Essential Amino Acid REFEED
- Primary Outcome Measures
Name Time Method Myofibrillar Fractional Synthetic Rate 6-10hrs Assessed by gas-chromatography-combustion-mass spectrometry, using incorporation of a stable isotope tracer (13-C-6 Phe)
- Secondary Outcome Measures
Name Time Method Muscle Protein Breakdown 6-10hrs By Arteriovenous limb balance
mTORC1 and AKT phosphorylation 6-10hrs Western Immunoblotting
Leg blood flow 6-10hrs Common femoral bulk flow (Doppler USS)
Trial Locations
- Locations (1)
School of Graduate Entry Medicine
🇬🇧Derby, United Kingdom