Exercise-Boosted Mitochondrial Remodeling in Parkinson's Disease

Oxidative Stress: A New Pathophysiological Pathway in Parkinson's Disease and a Potential Target of the Brain-Sport Crosstalk

Oxidative stress (OS), a condition that occurs when the balance between reactive oxygen species production and antioxidant defense mechanisms is disrupted, has been implicated in the pathogenesis of several neurological conditions, including neurodegenerative and vascular disorders. Ferroptosis is a mechanism mediating OS-induced damage, with growing evidence of specific involvement in both Parkinson's disease (PD) and ischemic stroke. Regular physical activity may have an antioxidant effect by increasing the production and activity of nonenzymatic and enzymatic antioxidants. Among the biological mediators of physical activity, irisin may act as an agent capable of inducing systemic changes and crossing the brain-blood barrier. This review aims to describe the main role of OS in the pathophysiology of PD, highlighting putative neurodegenerative mechanisms and emphasizing the potential targeting by physical activity as a possible shared preventive and symptomatic treatment approach.

Ameliorating Mitochondrial Dysfunction for the Therapy of Parkinson's Disease

Parkinson's disease (PD) is currently the second most incurable central neurodegenerative disease resulting from various pathogenesis. As the "energy factory" of cells, mitochondria play an extremely important role in supporting neuronal signal transmission and other physiological activities. Mitochondrial dysfunction can cause and accelerate the occurrence and progression of PD. How to effectively prevent and suppress mitochondrial disorders is a key strategy for the treatment of PD from the root. Therefore, the emerging mitochondria-targeted therapy has attracted considerable interest. Herein, the relationship between mitochondrial dysfunction and PD, the causes and results of mitochondrial dysfunction, and major strategies for ameliorating mitochondrial dysfunction to treat PD are systematically reviewed. The study also prospects the main challenges for the treatment of PD.

Survey of the Knowledge, Attitudes, and Practices of Neurologists Regarding Exercise in Parkinson's Disease

BACKGROUND AND PURPOSE

Exercise and physiotherapy can exert potentially beneficial effects on the motor and nonmotor features of Parkinson's disease (PD). We conducted an e-mail survey to assess the knowledge, attitudes, and practices of neurologists regarding exercise among patients with PD.

METHODS

A total of 222 neurologists from the Korean Movement Disorder Society and the Korean Society of Neurologists completed the survey and were classified into 4 clusters using the k-means clustering algorithm based on their institute types, the proportions of PD patients in their clinics, and the number of years working as neurologists.

RESULTS

Specialists working at referral hospitals (Clusters 1 and 2) were more confident than general neurologists (Clusters 3 and 4) about exercise improving the general motor features of PD. Specialists recommended more-frequent intense exercise compared with physicians not working at referral hospitals. The specialists in Cluster 1, representing >50% of PD patients in the clinics at referral hospitals, recommended exercise regardless of the disease stage, whereas the general neurologists in Clusters 3 and 4 recommended low-intensity exercise at an early stage of disease. Although most of the respondents agreed with the need for PD patients to exercise, less than half had prescribed rehabilitation or physiotherapy. More than 90% of the respondents answered that developing an exercise/physiotherapy protocol for PD would be helpful.

CONCLUSIONS

Specialists were more confident than general neurologists about the effect of exercise and recommended more-intense activities regardless of the disease stage. These results highlight the need to develop clinical practice guidelines and PD-specialized exercise protocols to provide optimal care for PD patients.

Mitochondrial Dysfunction in Skeletal Muscle of Rotenone-Induced Rat Model of Parkinson's Disease: SC-Nanophytosomes as Therapeutic Approach

The development of new therapeutic options for Parkinson's disease (PD) requires formulations able to mitigate both brain degeneration and motor dysfunctions. SC-Nanophytosomes, an oral mitochondria-targeted formulation developed with Codium tomentosum membrane polar lipids and elderberry anthocyanin-enriched extract, promote significant brain benefits on a rotenone-induced rat model of PD. In the present work, the effects of SC-Nanophytosome treatment on the skeletal muscle tissues are disclosed. It is unveiled that the rotenone-induced PD rat model exhibits motor disabilities and skeletal muscle tissues with deficient activity of mitochondrial complexes I and II along with small changes in antioxidant enzyme activity and skeletal muscle lipidome. SC-Nanophytosome treatment mitigates the impairment of complexes I and II activity, improving the mitochondrial respiratory chain performance at levels that surpass the control. Therefore, SC-Nanophytosome competence to overcome the PD-related motor disabilities should be also associated with its positive outcomes on skeletal muscle mitochondria. Providing a cellular environment with more reduced redox potential, SC-Nanophytosome treatment improves the skeletal muscle tissue's ability to deal with oxidative stress stimuli. The PD-related small changes on skeletal muscle lipidome were also counteracted by SC-Nanophytosome treatment. Thus, the present results reinforces the concept of SC-Nanophytosomes as a mitochondria-targeted therapy to address the neurodegeneration challenge.

Investigating the impact of physical activity on mitochondrial function in Parkinson's disease (PARKEX): Study protocol for A randomized controlled clinical trial

Parkinson's disease (PD) is characterized by the progressive dopaminergic neuron degeneration, resulting in striatal dopamine deficiency. Mitochondrial dysfunction and oxidative stress are associated with PD pathogenesis. Physical activity (PA) has been shown to ameliorate neurological impairments and to impede age-related neuronal loss. In addition, skin fibroblasts have been identified as surrogate indicators of pathogenic processes correlating with clinical measures. The PARKEX study aims to compare the effects of two different PA programs, analyzing the impact on mitochondrial function in patients' skin fibroblasts as biomarkers for disease status and metabolic improvement. Early-stage PD patients (n = 24, H&Y stage I to III) will be randomized into three age- and sex-matched groups. Group 1 (n = 8) will undergo basic physical training (BPT) emphasizing strength and resistance. Group 2 (n = 8) will undergo BPT combined with functional exercises (BPTFE), targeting the sensorimotor pathways that are most affected in PD (proprioception-balance-coordination) together with cognitive and motor training (Dual task training). Group 3 (n = 8) will serve as control (sedentary group; Sed). Participants will perform three sessions per week for 12 weeks. Assessment of motor function, quality of life, sleep quality, cognitive aspects and humor will be conducted pre- and post-intervention. Patient skin fibroblasts will be collected before and after the intervention and characterized in terms of metabolic remodeling and mitochondrial bioenergetics. Ethical approval has been given to commence this study. This trial is registered at clinicaltrials.gov (NCT05963425). Trial registration. https://classic.clinicaltrials.gov/ct2/history/NCT05963425.

Targeting mitochondrial dysfunction to salvage cellular senescence for managing neurodegeneration

Aging is an inevitable phenomenon that causes a decline in bodily functions over time. One of the most important processes that play a role in aging is senescence. Senescence is characterized by accumulation of cells that are no longer functional but elude the apoptotic pathway. These cells secrete inflammatory molecules that comprise the senescence associated secretory phenotype (SASP). Several essential molecules such as p53, Rb, and p16INK4a regulate the senescence process. Mitochondrial regulation has been found to play an important role in senescence. Reactive oxygen species (ROS) generated from mitochondria can affect cellular senescence by inducing the persistent DNA damage response, thus stabilizing the senescence. Evidently, senescence plays a major contributory role to the development of age-related neurological disorders. In this chapter, we discuss the role of senescence in the progression and onset of several neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis. Moreover, we also discuss the efficacy of certain molecules like MitoQ, SkQ1, and Latrepirdine that could be proven therapeutics with respect to these disorders by regulating mitochondrial activity.

The Role of Exercise in Maintaining Mitochondrial Proteostasis in Parkinson's Disease

Parkinson's disease (PD) is the second most common rapidly progressive neurodegenerative disease and has serious health and socio-economic consequences. Mitochondrial dysfunction is closely related to the onset and progression of PD, and the use of mitochondria as a target for PD therapy has been gaining traction in terms of both recognition and application. The disruption of mitochondrial proteostasis in the brain tissue of PD patients leads to mitochondrial dysfunction, which manifests as mitochondrial unfolded protein response, mitophagy, and mitochondrial oxidative phosphorylation. Physical exercise is important for the maintenance of human health, and has the great advantage of being a non-pharmacological therapy that is non-toxic, low-cost, and universally applicable. In this review, we investigate the relationships between exercise, mitochondrial proteostasis, and PD and explore the role and mechanisms of mitochondrial proteostasis in delaying PD through exercise.

Mitochondria: It is all about energy

Mitochondria play a key role in both health and disease. Their function is not limited to energy production but serves multiple mechanisms varying from iron and calcium homeostasis to the production of hormones and neurotransmitters, such as melatonin. They enable and influence communication at all physical levels through interaction with other organelles, the nucleus, and the outside environment. The literature suggests crosstalk mechanisms between mitochondria and circadian clocks, the gut microbiota, and the immune system. They might even be the hub supporting and integrating activity across all these domains. Hence, they might be the (missing) link in both health and disease. Mitochondrial dysfunction is related to metabolic syndrome, neuronal diseases, cancer, cardiovascular and infectious diseases, and inflammatory disorders. In this regard, diseases such as cancer, Alzheimer's, Parkinson's, amyotrophic lateral sclerosis (ALS), chronic fatigue syndrome (CFS), and chronic pain are discussed. This review focuses on understanding the mitochondrial mechanisms of action that allow for the maintenance of mitochondrial health and the pathways toward dysregulated mechanisms. Although mitochondria have allowed us to adapt to changes over the course of evolution, in turn, evolution has shaped mitochondria. Each evolution-based intervention influences mitochondria in its own way. The use of physiological stress triggers tolerance to the stressor, achieving adaptability and resistance. This review describes strategies that could recover mitochondrial functioning in multiple diseases, providing a comprehensive, root-cause-focused, integrative approach to recovering health and treating people suffering from chronic diseases.