Acute exercise protects against doxorubicin cardiotoxicity

Area of Science:

• Cardiology
• Exercise Physiology
• Pharmacology

Background:

• Doxorubicin (DOX) is a potent chemotherapeutic agent with dose-limiting cardiotoxicity.
• Existing methods to mitigate DOX cardiotoxicity have shown limited success.
• While chronic exercise is known to be cardioprotective, the effects of acute exercise on DOX-induced cardiac dysfunction are less understood.

Purpose of the Study:

• To investigate the cardioprotective effects of a single bout of acute endurance exercise prior to doxorubicin administration.
• To determine if acute exercise can prevent or reduce cardiac dysfunction induced by doxorubicin.

Main Methods:

• Male Sprague-Dawley rats were divided into groups: sedentary (SED) or acute exercise (EX) on a treadmill 24 hours before receiving doxorubicin (DOX) or saline (SAL).
• Cardiac function was assessed 5 days post-injection using an isolated perfused heart model (Langendorff).
• Myocardial lipid peroxidation was measured to assess oxidative stress.

Main Results:

• Doxorubicin treatment significantly impaired cardiac function (reduced pressures and contractility) and increased lipid peroxidation compared to saline controls.
• Rats that performed acute exercise before DOX treatment exhibited significantly preserved cardiac function compared to sedentary, DOX-treated rats.
• Lipid peroxidation levels in the exercise + DOX group were similar to the saline control group, indicating reduced oxidative stress.

Conclusions:

• A single bout of acute endurance exercise 24 hours before doxorubicin administration confers significant cardioprotection against DOX-induced cardiac dysfunction.
• Exercise-induced cardioprotection may be mediated, in part, by a reduction in reactive oxygen species generation.
• Acute exercise represents a potential strategy to mitigate the cardiotoxic side effects of doxorubicin chemotherapy.