Exercise responses in muscle myostatin, cytokines, and body composition were significantly greater in prediabetes than in rheumatoid arthritis (RA), consistent with impaired muscle remodeling in RA, according to a recent study. Previously sedentary persons with either RA (n=12) or prediabetes (n=9) completed a 10-week supervised high-intensity interval training program. At baseline and after training, participants underwent body composition and cardiopulmonary exercise testing, plasma collection, and vastus lateralis biopsies. An independent cohort of patients with RA (n=47) and age-, gender-, and body mass index (BMI)-matched non-RA controls (n=23) were used for additional analyses of galectin-3 inter-relationships. Researchers found:
- Exercise training did not reduce mean concentration of galectin-3, muscle cytokines, or muscle myostatin in persons with either RA or prediabetes.
- However, training-induced alterations varied among individuals and were associated with cardiorespiratory fitness and body composition changes.
- Improved cardiorespiratory fitness (increased absolute peak maximal oxygen consumption, or VO2) correlated with reductions in galectin-3.
- The association between increased lean mass and decreased muscle IL-6 association was stronger in prediabetes compared with RA; in prediabetes but not RA, lean mass increases occurred in conjunction with reductions in muscle myostatin.
Andonian BJ, Bartlett DB, Huebner JL, et al. Effect of high-intensity interval training on muscle remodeling in rheumatoid arthritis compared to prediabetes. Arthritis Care Res. 2018;20(1):283. doi:10.1186/s13075-018-1786-6.
Decreased skeletal muscle mass was associated with increased disability and mortality in patients with rheumatoid arthritis (RA). In this study, 12 previously sedentary patients with RA and 9 with pre-diabetes without overt diabetes or cardiovascular disease exercised 3 times per week for 10 weeks on graded treadmills. Following exercise, needle muscle biopsy was performed. Researchers found that increased muscle mass was related to reductions in muscle IL-6 and TNF-α. Plasma galectin-3 concentrations were also higher in RA patients than in healthy controls and associated with increased fat and decreased muscle mass, perhaps reflecting non-traditional cardiovascular disease risk factors.—Harold E. Paulus, M.D.; Emeritus Professor; University of California, Los Angeles; Division of Rheumatology.