Mitochondrial ROS and Aging: Understanding Exercise as a Preventive Tool

Abstract

Sarcopenia, which is characterized by reduction in muscle mass and strength, contributes to several age-related conditions, including insulin resistance and frailty. Despite the importance of maintaining muscle mass for healthy aging, the mechanisms contributing to sarcopenia are not fully elucidated. Nevertheless, mitochondria appear to play a key role in the underlying condition, and importantly, respond robustly to exercise interventions. Mitochondria are intracellular organelles largely attributed to maintaining ATP concentrations, however, the importance of this organelle in overall cellular homeostasis has been expanded in the last decades to include redox signaling, calcium homeostasis, inflammation, and apoptosis. Several lines of evidence suggest that mitochondrial bioenergetics are altered in aged skeletal muscle, resulting in an increase in reactive oxygen species (ROS) production, while conversely genetic/pharmacological approaches that attenuate mitochondrial ROS promote healthy aging and maintenance of muscle mass. These observations suggest that increased free radicals are one of the bases of the aging process and related sarcopenia. Here, we reviewed the current knowledge regarding mitochondrial function and redox balance in aged human skeletal muscle, highlighting the implications of redox unbalance on skeletal muscle mass maintenance and muscle health. Additionally, we describe the benefits of exercise and nutrition interventions in the context of improving mitochondrial bioenergetics and functional outcomes regarding skeletal muscle mass and function.

How Soon Do Metabolic Alterations and Oxidative Distress Precede the Reduction of Muscle Mass and Strength in Wistar Rats?

“…metabolism, leading to increased protein consumption and increased anaerobic metabolism (Abdel-Mageid et al 2018). These ndings are related to the reduction of peripheral sensitivity to insulin, where with advancing age metabolic changes precede structural changes, and even loss of muscle mass, strength and/or function(Brunetta et al 2020;Romeu Montenegro et al 2021). In this sense, our ndings reinforce those changes in energy metabolism occur long before any structural and macroscopic changes in the muscle are noticed.…”

The effect of sumac supplementation on insulin resistance, inflammation, oxidative stress, and antioxidant capacity in adults with metabolic syndrome: A randomized crossover clinical trial

“…In the current randomized crossover clinical trial, we illustrated that sumac supplementation (500 mg, twice a day) for 6 weeks in and MetS (Lakka & Laaksonen, 2007;Pitsavos et al, 2006). The compromised mitochondrial function due to physical inactivity would also make a negative spiral (Brunetta et al, 2020). Therefore, physical activity is the best medicine for MetS, especially when it is accompanied with a healthy diet (Lakka & Laaksonen, 2007;Pitsavos et al, 2006).…”

“…Physical inactivity and high‐calorie, low‐nutrient dietary intakes would result in fat accumulation especially visceral fat accumulation and consequently stress oxidative, inflammation, insulin resistance, and MetS (Lakka & Laaksonen, 2007; Pitsavos et al, 2006). The compromised mitochondrial function due to physical inactivity would also make a negative spiral (Brunetta et al, 2020). Therefore, physical activity is the best medicine for MetS, especially when it is accompanied with a healthy diet (Lakka & Laaksonen, 2007; Pitsavos et al, 2006).…”

A systematic review and meta-analysis demonstrating Klotho as an emerging exerkine

“…Nevertheless, ~ 150 min per week seems to be the optimal volume to induce S-Klotho changes. This might be due to the transient increase in oxidative stress, leading to an upregulation of the antioxidant system and anti-inflammatory profile [64][65][66][67][68] . Considering that high exercise intensities might cause renal artery vasoconstriction 69 , the hypoxia induced by a limited blood-flow may promote a transient oxidative stress that would increase the antioxidant system, including S-Klotho.…”