Omega 3 has a beneficial effect on ischemia/reperfusion injury, but cannot reverse the effect of stressful forced exercise.
OBJECTIVE
The beneficial effects of exercise in reducing the incidence of cardiovascular diseases are well known. Several studies have demonstrated that forced exercise (FE) could activate a stress response similar to a restrain stress. Previous studies suggest that heart protection to ischemic events would be improved by an omega 3 free fatty acid (omega3-FFA)-enriched diet. Here, we investigate the impact of stressful FE and an omega 3-FFA-enriched diet on cardiac tolerance to ischemic events over one month.


RESULTS
Twenty-four Wistar rats were randomly assigned to one of the following protocols: 1) Sedentary (SED) animals who were regularly fed; 2) sedentary animals who were given 1ml/day of fish oil for one month; 3) FE+omega3-FFA rats who were given 1ml/day of fish oil and forced to run on a motorized wheel for 30min every day, both for one month; and 4) FE animals were forced to exercise as group 3 and fed with a regular diet. At the end of the treatments an isolated heart preparation was performed. After a 30min global ischemic event and 2h reperfusion, hearts of sedentary-omega3 animals recovered about 37% of left ventricular developed pressure, whereas FE, omega3+FE and CTRL-SED animals recovered only about 15%, 5% and 8% respectively. Similarly, heart infarct size was significantly lower in sedentary-omega3 animals compared to animals in the three other groups.


CONCLUSIONS
Results indicate that one month of treatment with an omega3-FFA-enriched diet improves cardioprotection upon ischemic events, whereas FE leads to a reduced heart tolerance to ischemic events, which cannot be reversed by an omega3-FFA diet.
Mancardi
Daniele
D
Dipartimento di Scienze Cliniche e Biologiche, Università di Torino, Orbassano, Torino, Italy. daniele.mancardi@unito.it
Tullio
Francesca
F
Crisafulli
Antonio
A
Rastaldo
Raffaella
R
Folino
Anna
A
Penna
Claudia
C
Pagliaro
Pasquale
P
D000818:Animals; D004032:Diet; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D008297:Male; D009200:Myocardial Contraction; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D005082:Physical Exertion / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000502:physiology*
D015525:Fatty Acids, Omega-3