Exploring the links of skeletal muscle mitochondrial oxidative capacity, physical functionality, and mental well-being of cancer survivors

Physical impairments following cancer treatment have been linked with the toxic effects of these treatments on muscle mass and strength, through their deleterious effects on skeletal muscle mitochondrial oxidative capacity. Accordingly, we designed the present study to explore relationships of skeletal muscle mitochondrial oxidative capacity with physical performance and perceived cancer-related psychosocial experiences of cancer survivors. We assessed skeletal muscle mitochondrial oxidative capacity using in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS), measuring the postexercise phosphocreatine resynthesis time constant, τPCr, in 11 post-chemotherapy participants aged 34-70 years. During the MRS procedure, participants performed rapid ballistic knee extension exercise to deplete phosphocreatine (PCr); hence, measuring the primary study outcome, which was the recovery rate of PCr (τPCr). Patient-reported outcomes of psychosocial symptoms and well-being were assessed using the Patient-Reported Outcomes Measurement Information System and the 36-Item Short Form health survey (SF-36). Rapid bioenergetic recovery, reflected through a smaller value of τPCr was associated with worse depression (rho ρ = - 0.69, p = 0.018, and Cohen's d = - 1.104), anxiety (ρ = - 0.61, p = .046, d = - 0.677), and overall mental health (ρ = 0.74, p = 0.010, d = 2.198) scores, but better resilience (ρ = 0.65, p = 0.029), and coping-self efficacy (ρ = 0.63, p = 0.04) scores. This is the first study to link skeletal muscle mitochondrial oxidative capacity with subjective reports of cancer-related behavioral toxicities. Further investigations are warranted to confirm these findings probing into the role of disease status and personal attributes in these preliminary results.

Feasibility of DNA Methylation Age as a Biomarker of Symptoms and Resilience among Cancer Survivors with Multiple Chronic Conditions

This study aims to examine the feasibility of DNA methylation age as a biomarker for symptoms and resilience in cancer survivors with multiple chronic conditions (MCCs). We included ten participants from our parent study, an ongoing randomized control trial study. Participants' symptoms and resilience were assessed, and peripheral blood was collected. DNA methylation age calculation was performed using DNAge® analysis. Data were analyzed using Spearman's correlation analysis and the Mann-Whitney U test. Participants in the intervention group tended to have a decrease in DNA methylation age and age acceleration after completing an exercise program (mean difference = -0.83 ± 1.26). The change in DNA methylation age was significantly correlated with the change in resilience score (r = -0.897, p = 0.015). The preliminary results suggest that DNA methylation age can be a potential biomarker for improving resilience in cancer survivors with multiple chronic conditions. This finding is limited by the small sample size, and a larger study is needed.