Omega-3 Fatty Acids and Muscle Protein Synthesis

Condition(s) targeted: Healthy

Intervention: omega-3 fatty acids (Dietary Supplement); corn oil (Dietary Supplement)

Phase: N/A

Status: Recruiting

Sponsored by: Washington University School of Medicine

Official(s) and/or principal investigator(s):
Bettina Mittendorfer, PhD, Principal Investigator, Affiliation: Washington University School of Medicine

Overall contact:
Gordon I Smith, PhD, Phone: 362-4375, Email: gsmith@dom.wustl.edu

The purpose of this study is to determine whether omega-3 fatty acid supplementation influences muscle protein synthesis rates in young and older adults.

Official title: Omega-3 Fatty Acids and Muscle Protein Synthesis

Study design: Prevention, Randomized, Single Blind (Subject), Placebo Control, Parallel Assignment, Efficacy Study

Primary outcome: Evaluate the effect of omega-3 fatty acid supplementation on skeletal muscle protein synthesis rates both in the basal, postabsorptive state and in response to infusion of insulin and amino acids in young and older adults

Secondary outcome:

Evaluate the effect of omega-3 fatty acid supplementation on anabolic signaling pathways in skeletal muscle

Evaluate the effect of omega-3 fatty acid supplementation on inflammatory cytokines in the systemic circulation and inflammatory signaling pathways in skeletal muscle

Compare muscle protein synthesis rates between men and women in the basal, postabsorptive state and in response to insulin and amino acid infusion

Detailed description: Loss of muscle mass is a normal consequence of aging. The decline in muscle mass is estimated to be 0. 2-0. 5% per year from 60 years old onwards in healthy subjects with the decline worsened by chronic illness, poor appetite and diet, and reduced physical activity in the elderly. Increased morbidity is demonstrable with as little as a 5% loss of muscle

mass - therefore, treatments that can prevent or slow the progression of muscle loss with

aging are much desired.

A major cause for loss of muscle mass in advanced age appears to be an impaired ability to stimulate the synthesis of muscle protein in response to increased levels of amino acids (the building blocks of proteins) and insulin as occurs after eating because of low-grade inflammation and insulin resistance in muscle of old persons. We propose that long-chain omega-3 polyunsaturated fatty acids (fish oil) slow the loss of muscle mass because fish oil has anti-inflammatory properties and increases the sensitivity of muscle protein synthesis to insulin and amino acids. We will test this by studying the effect of fish oil supplementation on the muscle protein synthesis process in young and older adults.

Please note we have completed recruitment for the younger (18 to 45 year old) group and are therefore currently only recruiting individuals aged between 65 and 85 years.

Minimum age: 18 Years. Maximum age: 85 Years. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Body mass index (BMI) < 30 kg/m2;

- Age 18-45 yr; or

- Age 65-85 yr

Exclusion Criteria:

- Those taking medications known to affect substrate metabolism or medications that may

confound the findings from our study (synthetic steroids, glucocorticoids etc.);

- Those with evidence of significant organ system dysfunction (e. g. diabetes mellitis,

cirrhosis, hypo- or hyperthyroidism; hypertension);

- Body mass index > 30 kg/m2

- Age <18 yr, 45-65 yr or > 85 yr

- Those performing >1. 5h of exercise/wk

Gordon I Smith, PhD, Phone: 362-4375, Email: gsmith@dom.wustl.edu

Washington University in Saint Louis, Saint Louis, Missouri 63110, United States; Recruiting
Gordon I Smith, PhD, Phone: 314-362-4375, Email: gsmith@dom.wustl.edu
Bettina Mittendorfer, PhD, Principal Investigator

Starting date: June 2007
Ending date: December 2009
Last updated: August 3, 2009