In mouse studies, researchers found that exercising prior to developing cancer was associated with slower tumour growth and helped reduce the effects of a cachexia, a cancer complication also known as wasting syndrome.
Cachexia is a metabolic wasting disorder that affects up to 80% of patients with advanced cancer and is associated with about a third of all deaths from cancer. Cachexia is characterised by severe progressive muscle wasting, a decline in heart structure and function and an overall poorer quality of life.
“Most exercise, especially aerobic exercise, is easily accessible and affordable,” said Louisa Tichy, a graduate student in Traci Parry’s lab at the University of North Carolina at Greensboro. “Therefore, engaging in consistent aerobic exercise such as running is a cost-effective way to reduce the risk of cancer and cancer complications.”
Tichy presented the research at the American Society for Investigative Pathology annual meeting.
Previous research has shown that exercise could have anti-inflammatory effects and might positively impact cancer cachexia by slowing its development and preserving cardiac structure and function. However, very few studies have focused on preconditioning.
“Our preclinical study indicated that preconditioning – or exercise prior to tumour bearing – appears to play an important cardioprotective role during cancer cachexia by preserving cardiac structure and function,” said Tichy. “It also helped stunt tumour growth, even when animals did not exercise during the tumour-bearing period.”
For the new study, the researchers studied mice that exercised on a treadmill for eight weeks and non-exercising mice. After the eight weeks, the researchers induced cancer in some of the exercised mice and some sedentary mice while keeping some mice from both groups cancer-free to act as controls.
Mice with cancer and a sedentary lifestyle were found to have poorer heart function – as measured with echocardiography – than the mice that exercised prior to cancer induction. Also, exercising mice had a smaller tumour volume and a 60% smaller tumour mass than the sedentary mice.
“This data is crucial in identifying the significance of exercise and the best timing of exercise as a protective and preventative measure against the detrimental effects of cancer cachexia,” said Tichy.
Understanding how the underlying proteins and pathways are affected by cancer and exercise can be used to inform exercise interventions. The researchers say that devising safe and effective exercise interventions for cancer patients would require evaluating the best intensity, duration and timing of exercise in preclinical models before human tests.
Source: EurekAlert!
