title: Gene expression profile of rat left ventricles reveals persisting changes following chronic mild exercise protocol: implications for cardioprotection.
abstract: BACKGROUND
  Epidemiological studies showed that physical exercise, specifically moderate lifelong training, is protective against cardiovascular morbidity and mortality. Most experimental work has focused into the effects and molecular mechanisms underlying intense, rather than mild exercise, by exploring the acute effect of training. Our study aims at investigating the cardioprotective effect of mild chronic exercise training and the gene expression profile changes at 48 hrs after the exercise cessation. Rats were trained at mild intensity on a treadmill: 25 m/min, 10%incline, 1 h/day, 3 days/week, 10 weeks; about 60% of the maximum aerobic power. By Affymetrix technology, we investigated the gene expression profile induced by exercise training in the left ventricle (LV) of trained (n = 10) and control (n = 10) rats. Cardioprotection was investigated by ischemia/reperfusion experiments (n = 10 trained vs. n = 10 control rats).
  
  
  RESULTS
  Mild exercise did not induce cardiac hypertrophy and was cardioprotective as demonstrated by the decreased infarct size (p = 0.02) after ischemia/reperfusion experiments in trained with respect to control rats. Ten genes and 2 gene sets (two pathways) resulted altered in LV of exercised animals with respect to controls. We validated by real-time PCR the increased expression of four genes: similar to C11orf17 protein (RGD1306959), caveolin 3, enolase 3, and hypoxia inducible factor 1 alpha. Moreover, caveolin 3 protein levels were higher in exercised than control rats by immunohistochemistry and Western Blot analysis. Interestingly, the predicted gene similar to C11orf17 protein (RGD1306959) was significantly increased by exercise. This gene has a high homology with the human C11orf17 (alias: protein kinase-A interacting protein 1 or breast cancer associated gene 3). This is the first evidence that this gene is involved in the response to the exercise training.
  
  
  CONCLUSIONS
  Our data indicated that few, but significant, genes characterize the gene expression profile of the rat LV, when examined 48 hrs since the last training section and that mild exercise training determines cardioprotection without the induction of hypertrophy.
authors: Department of Medical and Surgical Critical Care and Center of Research, Transfer and High Education, DENOTHE, University of Florence, Florence, Italy. betti.giusti@unifi.it
authors: Betti
authors: B
authors: Giusti
authors: Marina
authors: M
authors: Marini
authors: Luciana
authors: L
authors: Rossi
authors: Ilaria
authors: I
authors: Lapini
authors: Alberto
authors: A
authors: Magi
authors: Andrea
authors: A
authors: Capalbo
authors: Rosa
authors: R
authors: Lapalombella
authors: Simona
authors: S
authors: di Tullio
authors: Michele
authors: M
authors: Samaja
authors: Fabio
authors: F
authors: Esposito
authors: Vittoria
authors: V
authors: Margonato
authors: Maria
authors: M
authors: Boddi
authors: Rosanna
authors: R
authors: Abbate
authors: Arsenio
authors: A
authors: Veicsteinas
mesh_terms: D000818:Animals; D006332:Cardiomegaly / Q000235:genetics; D020869:Gene Expression Profiling; D006352:Heart Ventricles / Q000378:metabolism*; D008297:Male; D023421:Models, Animal; D015428:Myocardial Reperfusion Injury / Q000235:genetics; D010805:Physical Conditioning, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors