Exercise Training Attenuates Ubiquitin-Proteasome Pathway and Increases the Genes Related to Autophagy on the Skeletal Muscle of Patients With Inflammatory Myopathies.

BACKGROUND/OBJECTIVE: The aim of this study was to evaluate the effects of exercise training on the ubiquitin-proteasome system (UPS) and genes related to autophagy on the skeletal muscle of patients with dermatomyositis (DM) and immune-mediated necrotizing myopathies (IMNMs). METHODS: Seven DM patients and 6 IMNM patients were treated for 12 weeks with a twice-weekly aerobic and resistance training exercise program. Aerobic capacity, muscle strength, and expression of genes in the skeletal muscle related to UPS and to autophagy were evaluated at the baseline and after the intervention. Moreover, only at the baseline, 10 healthy control individuals were also evaluated. RESULTS: The age of DM and IMNM patients was 49.8 and 58.5 years, respectively. Genes related to UPS were upregulated, whereas genes related to autophagy and antioxidative systems were downregulated only in the DM group when compared with control group. After completion of the exercise training program, several genes related to UPS were downregulated, whereas genes related to autophagy, mitochondrial pathways, and antioxidative systems were upregulated in both the DM and IMNM groups. CONCLUSIONS: Exercise training can increase genes related to autophagy, mitophagy, and lysosomal biogenesis in the skeletal muscle of patients. These results suggest an increase in the recycling of damaged proteins and organelles, which may also contribute to the performance and endurance of skeletal muscles in these patients. Furthermore, in patients with myositis, exercise training led to a decrease in genes related to UPS and an increase in genes related to antioxidative capacity. Therefore, this may also contribute to an attenuation of skeletal muscle loss and of the deleterious effects of oxidative stress on the skeletal muscle of these patients.

Safety of Atorvastatin in Patients With Stable Systemic Autoimmune Myopathies: A Pilot Longitudinal Study.

BACKGROUND/OBJECTIVE: Patients with systemic autoimmune myopathies (SAMs) have high prevalence of dyslipidemia and, consequently, possible endothelial dysfunction and vascular stiffness. Our objective was to evaluate the possible benefits on endothelial function and vascular stiffness, as well as adverse effects of atorvastatin in SAMs. METHODS: A pilot longitudinal, double-blind, randomized, placebo-controlled study was conducted. Twenty-four of 242 patients were randomized at a 2:1 ratio to receive atorvastatin (20 mg/d) or placebo for a period of 12 weeks. Demographic data, comorbidities, and clinical and laboratory parameters, as well as endothelial function and arterial stiffness, were evaluated. RESULTS: Of the 24 randomized patients, 4 patients were excluded, with remaining 20 patients (14 in the atorvastatin group and 6 in the placebo group). The mean age of the patients was 49.0 years, and 75% of the patients were female. At baseline, the demographic data, disease status, treatment, cardiovascular comorbidities, and risk factors were comparable between the atorvastatin and placebo groups. After 12 weeks of follow-up of atorvastatin therapy, no improvements were observed for endothelial function and arterial stiffness in either group (p > 0.05). As expected, a significant reduction in total and low-density lipoprotein cholesterol levels was observed. During the study, no clinical intercurrences or disease relapses were observed in either group. CONCLUSIONS: The atorvastatin drug attenuated low-density lipoprotein cholesterol without worsening clinical outcomes in SAMs. No change was observed for endothelial function and arterial stiffness. Additional studies, with long-term follow-up time and different atorvastatin dosage, are needed to corroborate the results of this study.

Feasibility, safety and efficacy of exercise training in immune-mediated necrotising myopathies: a quasi-experimental prospective study.

OBJECTIVES: To evaluate the feasibility, safety and efficacy of exercise training in patients with immune-mediated necrotising myopathies (IMNM). METHODS: Eight consecutive sedentary patients with IMNM (5 anti-signal recognition particle and 3 anti-hydroxy-methyl-glutaryl coenzyme A reductase) were engaged in this study. Disease status was based on International Myositis Assessment and Clinical Studies Group (IMACS) core set measures. Physical performance was evaluated by cardiopulmonary exercise test, repetition maximum (RM) protocol, handgrip dynamometry, sit-to-stand (STS) and timed up-and-go (TUG) tests. All these parameters were measured at baseline and after a 12-week, twice-a-week, supervised exercise training comprising aerobic and strength exercises. RESULTS: Patients (aged 61 years on average) were very disabled at the beginning of the disease (mean duration of 17.7 months), but after being aggressively treated with a treat-to-target approach, they presented only mild symptoms that were well-controlled with oral immunosuppression and low disease status scores by the time of the exercise intervention. No disease relapsing, worsening of the IMACS set scores or adverse events were observed throughout the training period. Patients also increased aerobic capacity (e.g. time to achieve anaerobic threshold and time to achieve exhaustion), muscle strength (e.g. 1RM bench press) and function (e.g. STS test). CONCLUSIONS: Supervised exercise training did not impair disease status and seemed to be feasible, safe and effective in patients with IMNM. Moreover, exercise training increased aerobic capacity, muscle strength and function, suggesting that this could be a novel potential coadjuvant therapy in IMNM.

Exercise training attenuates skeletal muscle fat infiltration and improves insulin pathway of patients with immune-mediated necrotizing myopathies and dermatomyositis.

Objectives: This study aims to evaluate the effects of exercise training on intramuscular lipid content and genes related to insulin pathway in patients with systemic autoimmune myopathies (SAMs). Patients and methods: Between January 2016 and May 2019, a total of seven patients with dermatomyositis (DM; 3 males, 4 females; mean age: 49.8±2.3 years; range, 43 to 54 years), six with immune mediated necrotizing myopathy (IMNM; 3 males, 3 females; mean age: 58.5±10.6 years; range, 46 to 74 years), and 10 control individuals (CTRL group; 4 males, 6 females; mean age: 48.7±3.9 years; range, 41 to 56 years) were included. The muscle biopsy before and after the intervention was performed to evaluate the intramuscular lipid content. Patients underwent a combined exercise training program for 12 weeks. Skeletal muscle gene expression was analyzed and the DM versus CTRL group, DM pre- and post-, and IMNM pre- and post-intervention were compared. Results: The DM group had a higher intramuscular lipid content in type II muscle fibers compared to the CTRL group. After the intervention, there was a reduction of lipid content in type I and II fibers in DM and IMNM group. The CTRL group showed a significantly higher expression of genes related to insulin and lipid oxidation pathways (AMPKß2, AS160, INSR, PGC1-α, PI3K, and RAB14) compared to the DM group. After exercise training, there was an increase gene expression related to insulin pathway and lipid oxidation in DM group (AMPKß2, AS160, INSR, PGC1-α, PI3K, and RAB14) and in IMNM group (AKT2, AMPKß2, RAB10, RAB14, and PGC1-α). Conclusion: Exercise training attenuated the amount of fat in type I and II muscle fibers in patients with DM and IMNM and increased gene expression related to insulin pathways and lipid oxidation in DM and IMNM. These results suggest that exercise training can improve the quality and metabolic functions of skeletal muscle in these diseases.

Exercise training attenuates insulin resistance and improves ß-cell function in patients with systemic autoimmune myopathies: a pilot study.

INTRODUCTION/OBJECTIVES: To assess the effects of exercise training on insulin resistance and ß-cell function in patients with systemic autoimmune myopathies (SAMs). METHOD: This quasi-experimental, prospective study includes 9 patients with SAMs (six with dermatomyositis, two with antisynthetase syndrome, and one with polymyositis). Patients were submitted to a 12-week, twice a week, exercise training program comprising aerobic and resistance exercises. Baseline and after the intervention, we evaluated disease status, aerobic capacity, muscle strength, body composition, insulin resistance, and ß-cell function parameters. RESULTS: The patients have a mean age of 46.7 years and stable disease. No clinical or laboratory parameter impairment was observed after the intervention. Compared with baseline, aerobic capacity, muscle strength, and function increased after 12 weeks (P < 0.05), while no changes were observed for body composition. Data from the oral glucose tolerance test showed that exercise did not change glucose area under the curve (AUC), whereas insulin and C-peptide AUC decreased significantly (P < 0.05). Furthermore, Matsuda index and HOMA2 percentage (both surrogates of insulin resistance) also improved (P < 0.05). CONCLUSION: Exercise training improved aerobic capacity, muscle strength, and muscle function in patients with SAMs. In addition, exercise training led to an attenuation of insulin resistance and improvements in ß-cell function parameters. These data indicate that exercise training can mitigate metabolic impairments, attenuating the cardiovascular risk in SAMs.Key Points• Exercise training improved aerobic capacity, muscle strength, and function without disease impairment• Exercise training was capable of improve insulin resistance and ß-cell function in patients with SAM• These results suggest that exercise can mitigate metabolic impairments in patients with SAM, attenuating the cardiovascular risk.

Physical exercise among patients with systemic autoimmune myopathies.

Systemic autoimmune myopathies (SAMs) are a heterogeneous group of rare systemic autoimmune diseases that primarily affect skeletal muscles. Patients with SAMs show progressive skeletal muscle weakness and consequent functional disabilities, low health quality, and sedentary lifestyles. In this context, exercise training emerges as a non-pharmacological therapy to improve muscle strength and function as well as the clinical aspects of these diseases. Because many have feared that physical exercise exacerbates inflammation and consequently worsens the clinical manifestations of SAMs, it is necessary to evaluate the possible benefits and safety of exercise training among these patients. The present study systematically reviews the evidence associated with physical training among patients with SAMs.