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The effect of high intensity interval training on cardioprotection against ischemia-reperfusion injury in wistar rats.

Rahimi M, Shekarforoush S, Asgari AR, Khoshbaten A, Rajabi H, Bazgir B, Mohammadi MT, Sobhani V, Shakibaee A - EXCLI J (2015)

Bottom Line: In comparison of sedentary group, IS significantly decreased in EX-IR1 and EX-IR7 groups (50 and 35 %, respectively), but not in EX-IR14 group (19 %).There were no significant changes in ischemia-induced arrhythmia between exercised and sedentary rats.This protective effect can be sustained for at least one week following the cessation of the training.

View Article: PubMed Central - PubMed

Affiliation: Exercise Physiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

ABSTRACT
The aims of the present study were to determine whether short term high intensity interval training (HIIT) could protect the heart against ischemia reperfusion (IR) injury; and if so, to evaluate how long the exercise-associated protection can be lasted. Sixty-three rats were randomly assigned into sedentary (n = 15), sham (n = 7), and exercise groups (n = 41). Rats in the exercise groups performed 5 consecutive days of HIIT on treadmill: 5 min warm up with 50 % VO2max, 6×2 min with 95-105 % VO2max (about 40 to 45 m/min), 5×2 min recovery with 65-75 % VO2max (about 28 to 32 m/min), and 3 min cool down with 50 % VO2max, all at 0 % grade. Animals exposed to an in vivo cardiac IR surgery, performed at days 1, 7, and 14 following the final exercise session. Ischemia-induced arrhythmias, myocardial infarct size (IS), plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities were measured in all animals. Compared to sedentary rats, exercised animals sustained less IR injury as evidenced by a lower size of infarction and lower levels of LDH and CK at day one and day 7 post exercise. In comparison of sedentary group, IS significantly decreased in EX-IR1 and EX-IR7 groups (50 and 35 %, respectively), but not in EX-IR14 group (19 %). The exercise-induced cardioprotection disappeared 14 days following exercise cessation. There were no significant changes in ischemia-induced arrhythmia between exercised and sedentary rats. The results clearly demonstrate that HIIT protects the heart against myocardial IR injury. This protective effect can be sustained for at least one week following the cessation of the training.

No MeSH data available.


Related in: MedlinePlus

The ratio of myocardial area at risk to left ventricle area (AAR/LV %) and infarct size to area at risk (IS/AAR %) in rats subjected to 30 min ischemia and 90 min of reperfusion. Red areas indicate myocardium within the area at risk for infarction and whitish areas indicate infarcted tissue. CO-IR, control + ischemia–reperfusion; EX-IR1, exercise + IR performed after a day of rest; EX-IR7, exercise + IR performed after 7 days of rest; EX-IR14, exercise + IR performed after 14 days of rest. *P < 0.05 and **P < 0.01 vs CO-IR group
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Figure 2: The ratio of myocardial area at risk to left ventricle area (AAR/LV %) and infarct size to area at risk (IS/AAR %) in rats subjected to 30 min ischemia and 90 min of reperfusion. Red areas indicate myocardium within the area at risk for infarction and whitish areas indicate infarcted tissue. CO-IR, control + ischemia–reperfusion; EX-IR1, exercise + IR performed after a day of rest; EX-IR7, exercise + IR performed after 7 days of rest; EX-IR14, exercise + IR performed after 14 days of rest. *P < 0.05 and **P < 0.01 vs CO-IR group

Mentions: The effects of HIIT on post-exercise infarct size at each time point are presented in Figure 2(Fig. 2). Thirty minutes of ischemia followed by 90 min of reperfusion resulted in a marked myocardial infarction in both sedentary and exercised rats. Exercise was associated with a decrease in infarct area in all exercised groups regardless of detraining time. The result demonstrated that mean of AAR did not differ significantly among groups (p = 0.74), whereas there was significant difference in IS result (p = 0.001). The result of Tukey test indicated that IS was decreased significantly in the EX-IR1 (p = 0.001) and EX-IR7 (p = 0.02) groups, but not in EX-IR14 (p = 0.33), compared with the CO-IR group. In comparision of control group, IS decreased 50, 35, and 19 % in EX-IR1, EX-IR7, and EX-IR14 respectively.


The effect of high intensity interval training on cardioprotection against ischemia-reperfusion injury in wistar rats.

Rahimi M, Shekarforoush S, Asgari AR, Khoshbaten A, Rajabi H, Bazgir B, Mohammadi MT, Sobhani V, Shakibaee A - EXCLI J (2015)

The ratio of myocardial area at risk to left ventricle area (AAR/LV %) and infarct size to area at risk (IS/AAR %) in rats subjected to 30 min ischemia and 90 min of reperfusion. Red areas indicate myocardium within the area at risk for infarction and whitish areas indicate infarcted tissue. CO-IR, control + ischemia–reperfusion; EX-IR1, exercise + IR performed after a day of rest; EX-IR7, exercise + IR performed after 7 days of rest; EX-IR14, exercise + IR performed after 14 days of rest. *P < 0.05 and **P < 0.01 vs CO-IR group
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4555214&req=5

Figure 2: The ratio of myocardial area at risk to left ventricle area (AAR/LV %) and infarct size to area at risk (IS/AAR %) in rats subjected to 30 min ischemia and 90 min of reperfusion. Red areas indicate myocardium within the area at risk for infarction and whitish areas indicate infarcted tissue. CO-IR, control + ischemia–reperfusion; EX-IR1, exercise + IR performed after a day of rest; EX-IR7, exercise + IR performed after 7 days of rest; EX-IR14, exercise + IR performed after 14 days of rest. *P < 0.05 and **P < 0.01 vs CO-IR group
Mentions: The effects of HIIT on post-exercise infarct size at each time point are presented in Figure 2(Fig. 2). Thirty minutes of ischemia followed by 90 min of reperfusion resulted in a marked myocardial infarction in both sedentary and exercised rats. Exercise was associated with a decrease in infarct area in all exercised groups regardless of detraining time. The result demonstrated that mean of AAR did not differ significantly among groups (p = 0.74), whereas there was significant difference in IS result (p = 0.001). The result of Tukey test indicated that IS was decreased significantly in the EX-IR1 (p = 0.001) and EX-IR7 (p = 0.02) groups, but not in EX-IR14 (p = 0.33), compared with the CO-IR group. In comparision of control group, IS decreased 50, 35, and 19 % in EX-IR1, EX-IR7, and EX-IR14 respectively.

Bottom Line: In comparison of sedentary group, IS significantly decreased in EX-IR1 and EX-IR7 groups (50 and 35 %, respectively), but not in EX-IR14 group (19 %).There were no significant changes in ischemia-induced arrhythmia between exercised and sedentary rats.This protective effect can be sustained for at least one week following the cessation of the training.

View Article: PubMed Central - PubMed

Affiliation: Exercise Physiology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

ABSTRACT
The aims of the present study were to determine whether short term high intensity interval training (HIIT) could protect the heart against ischemia reperfusion (IR) injury; and if so, to evaluate how long the exercise-associated protection can be lasted. Sixty-three rats were randomly assigned into sedentary (n = 15), sham (n = 7), and exercise groups (n = 41). Rats in the exercise groups performed 5 consecutive days of HIIT on treadmill: 5 min warm up with 50 % VO2max, 6×2 min with 95-105 % VO2max (about 40 to 45 m/min), 5×2 min recovery with 65-75 % VO2max (about 28 to 32 m/min), and 3 min cool down with 50 % VO2max, all at 0 % grade. Animals exposed to an in vivo cardiac IR surgery, performed at days 1, 7, and 14 following the final exercise session. Ischemia-induced arrhythmias, myocardial infarct size (IS), plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities were measured in all animals. Compared to sedentary rats, exercised animals sustained less IR injury as evidenced by a lower size of infarction and lower levels of LDH and CK at day one and day 7 post exercise. In comparison of sedentary group, IS significantly decreased in EX-IR1 and EX-IR7 groups (50 and 35 %, respectively), but not in EX-IR14 group (19 %). The exercise-induced cardioprotection disappeared 14 days following exercise cessation. There were no significant changes in ischemia-induced arrhythmia between exercised and sedentary rats. The results clearly demonstrate that HIIT protects the heart against myocardial IR injury. This protective effect can be sustained for at least one week following the cessation of the training.

No MeSH data available.


Related in: MedlinePlus