Exercise, Neuroprotective Exerkines, and Parkinson's Disease: A Narrative Review

Abstract

Parkinson's disease (PD) is a prevalent neurodegenerative disease in which treatment often includes an exercise regimen. Exercise is neuroprotective in animal models of PD, and, more recently, human clinical studies have verified exercise's disease-modifying effect. Aerobic exercise and resistance training improve many of PD's motor and non-motor symptoms, while neuromotor therapy and stretching/flexibility exercises positively contribute to the quality of life in people with PD. Therefore, understanding the role of exercise in managing this complex disorder is crucial. Exerkines are bioactive substances that are synthesized and released during exercise and have been implicated in several positive health outcomes, including neuroprotection. Exerkines protect neuronal cells in vitro and rodent PD models in vivo. Aerobic exercise and resistance training both increase exerkine levels in the blood, suggesting a role for exerkines in the neuroprotective theory. Many exerkines demonstrate the potential for protecting the brain against pathological missteps caused by PD. Every person (people) with Parkinson's (PwP) needs a comprehensive exercise plan tailored to their unique needs and abilities. Here, we provide an exercise template to help PwP understand the importance of exercise for treating PD, describe barriers confronting many PwP in their attempt to exercise, provide suggestions for overcoming these barriers, and explore the role of exerkines in managing PD. In conclusion, exercise and exerkines together create a powerful neuroprotective system that should contribute to slowing the chronic progression of PD.

Keywords: Alzheimer’s disease; Parkinson’s disease; aerobic exercise; exercise; exerkines; myokines; neurodegenerative disease; neuroprotective theory; resistance training.

Figure 1

Etiology of Parkinson’s disease. The major causes of the disorder are given in alphabetical order. Abbreviation: CNS, central nervous system.

Figure 2

Overview of exercise and the role of neuroprotective exerkines. The molecular mechanisms underlying the protective/regenerative effects of exerkines are under active investigation. Abbreviations: ND, neurodegenerative; TBI, traumatic brain injury; PTSD, post-traumatic stress disorder.

Figure 3

Parkinson’s disease exercise pyramid. The pyramid consists of four types of exercise: aerobic exercise, resistance training, neuromotor therapy, and stretching/flexibility exercises. On the left side are the recommended days per week, a suggested % HRmax for aerobic exercise and a % max effort for resistance training (given for a participant with early-stage PD; please see the text for suggestions at other stages of PD). On the right side is a description of the kind of exercises best represented by each category.

Figure 4

Potential role of neuroprotective exerkines to slow the progression of Parkinson’s disease.