Abstract
Sarcopenia, defined by loss of muscle mass and function, is a common complication of chronic kidney disease (CKD). Evidence suggests that mitochondrial dysfunction is one of the underlying causes of sarcopenia in CKD. This study recruited participants with moderate to severe non-dialysis CKD. Participants underwent an exercise intervention consisting of home-based video supervised and self-directed exercise sessions, 3 times a week, for 12 weeks. Exercise consisted of body weight high-intensity interval training, strength training and moderate intensity walking. Before and after the exercise intervention period, physical function and mitochondrial function were assessed. Mitochondrial function was measured ex vivo on vastus lateralis muscle biopsy samples and peripheral blood mononuclear cells (PBMC)s by high resolution respirometry using an Oroboros O2k FluoroRespirometer. Reactive oxygen species (ROS) production was also assessed in skeletal muscle homogenate alongside respiration using Amplex UltraRed to detect H2O2 in the Oroboros O2k FluoroRespirometer. We found that the home-based exercise intervention improved physical functioning as measured by the six-minute walk test. Respiration in PBMCs decreased after the exercise intervention. In skeletal muscle homogenate, there was an increase in respiration and no change in hydrogen peroxide production after the exercise intervention, resulting in a decrease in the H2O2/O2 ratio. These data indicate that a home-based video supervised exercise intervention can improve physical functioning and respiratory capacity of skeletal muscle without increasing ROS production in CKD patients.