Exercise Training as Therapeutic Approach in Cancer Cachexia: A Review of Potential Anti-inflammatory Effect on Muscle Wasting

Abstract

Cachexia is a multifactorial inflammatory syndrome with high prevalence in cancer patients. It is characterized by a metabolic chaos culminating in drastic reduction in body weight, mainly due to skeletal muscle and fat depletion. Currently, there is not a standard intervention for cachexia, but it is believed that a dynamic approach should be applied early in the course of the disease to maintain or slow the loss of physical function. The present review sought to explain the different clinical and experimental applications of different models of exercise and their contribution to a better prognosis of the disease. Here the advances in knowledge about the application of physical training in experimental models are elucidated, tests that contribute substantially to elucidate the cellular and biochemical mechanisms of exercise in different ways, as well as clinical trials that present not only the impacts of exercise in front cachexia but also the challenges of its application in clinical practice.

Keywords: aerobic; muscle atrophy; muscle wasting; neoplasms; resistance; systemic inflammation; therapeutic exercise; tumor.

FIGURE 1

Tumor-induced systemic inflammation and metabolism impact. Among the numerous cytokines released by the tumor, TNFα, IL-6, and IL-1β stand out. These, in turn, are capable of acting on different organs and systems, promoting inflammation, metabolic and immunological changes that directly and indirectly affect essential organs in the pathophysiology of cachexia, such as skeletal striated muscle and white and brown adipose tissue. Continuous arrows refer to mechanisms already described, and dotted arrows refer to mechanisms not yet known.

FIGURE 2

Main physiological effects of aerobic and anaerobic exercise training. Both types of exercise. Both different exercise types promote numerous physiological changes that result in improved physical capacities and health indicators, resulting in increased life expectancy (survival). Aerobic exercise is represented by the bicycle, and the dumbbells describe anaerobic exercise. LME, Local Muscular Endurance.

FIGURE 3

Effects of exercise training in cachexia markers. The effects of different physical training types on cachexia symptoms and markers are evident in the literature; however, in a majority way through tests on experimental models. The changes promoted in skeletal muscle and inflammation control are highlighted as the leading promoters of a better prognosis and increased life expectancy elevated by exercise training.