# EFFECT OF EXERCISE ON PROTEIN DEGRADATION

> **NIH NIH R01** · EAST CAROLINA UNIVERSITY · 1991 · $115,265

## Abstract

Although the major fuels used during exercise are carbohydrates and fats
the contribution made by protein is important.  The breakdown of protein
leads to amino acids that can replenish the citric acid cycle
intermediates that are lost by oxidative processes when the carbohydrate
stores are low.  The long term objectives of this research are to
determine how the rate of muscle protein degradation is affected by
exercise, the mechanism of exercise-induced protein degradation, and the
physiological regulation of protein degradation.  The effect of exercise
on protein degradation is controversial because a through study has not
been performed.  The differing results of previous studies can be
explained by the central hypothesis in this proposal.  This hypothesis is
that the effect of exercise on muscle protein degradation depends on the
type of muscle protein studied, the type of exercise performed, and the
time the measurements were made in relation to the time the exercise was
performed.  In the proposed studies the rate of total and myofibrillar
protein degradation will be determined by measuring the release of
tyrosine and 3-methylhistidine, respectively, from the perfused rat
hindlimb.  These measurements will be made before, during, and after
exercise.  The contribution of muscle damage to the effect of exercise on
muscle protein degradation will be determined by subjecting some of the
animals to muscle damaging eccentric exercise.  The mechanism off
exercise-induced protein degradation will be probed by measuring the
initial events in the degradation of muscle proteins, determining how
lysosomes are involved, and determining how the activity of muscle
proteinases and their inhibitors are altered during and after exercise.
The effect of physiological regulators on the exercise-induced changes in
the rate of protein degradation will be studied by changing the
concentrations of these regulators either directly or indirectly by the
use of inhibitors.  The regulators studied will include the energy
charge, H+, Ca2+, insulin, leucine, and PGE2.  The results of these
proposed studies will not only clear up the controversy concerning the
effect of exercise on protein metabolism, but will also yield important
basic information necessary for an understanding of the mechanism and
regulation of protein degradation in general.  This information could
find application in the treatment of muscle wasting conditions such as
fever, sepsis, traumatic injuries, and cancer.

## Key facts

- **NIH application ID:** 3159318
- **Project number:** 5R01AR039299-03
- **Recipient organization:** EAST CAROLINA UNIVERSITY
- **SAM.gov UEI:** HWPEKM8VFTJ9
- **Principal Investigator:** GEORGE J KASPEREK
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1991
- **Award amount:** $115,265
- **Award type:** 5
- **Project period:** 1989-06-15 → 1994-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3159318

## Citation

> US National Institutes of Health, RePORTER application 3159318, EFFECT OF EXERCISE ON PROTEIN DEGRADATION (5R01AR039299-03). Retrieved via MORVS 2026-10-24 from https://api.morvs.ai/grant/nih/3159318. Licensed CC0.

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