Many obese elderly persons have impaired physical function associated with an increased chronic inflammatory response. We evaluated 12 wk of exercise (aerobic and resistance) or 12 wk of weight loss (∼7% reduction) on skeletal muscle mRNAs for toll-like receptor-4 (TLR-4), mechanogrowth factor (MGF), TNF-α, and IL-6 in 16 obese (body mass index 38 ± 2 kg/m 2) older (69 ± 1 yr) physically frail individuals. Vastus lateralis muscle biopsies were obtained at 0 and 12 wk and analyzed by real-time RT-PCR. Body composition was assessed by dual-energy x-ray absorptiometry. Body weight decreased (-7.5 ± 1.2 kg, P = 0.001) in the weight loss group but not in the exercise group (-0.3 ± 0.8 kg, P = 0.74). Fat-free mass (FFM) decreased (-2.9 ± 0.6 kg, P = 0.010) in the weight loss group and increased (1.6 ± 0.6 kg, P = 0.03) in the exercise group. Exercise resulted in a 37% decrease in TLR-4 mRNA (P < 0.05) while weight loss had no significant effect. Additionally, exercise led to a significant (50%) decrease in IL-6 and TNF-α mRNA (P < 0.05) while weight loss had no effect. Exercise increased MGF mRNA (∼2 fold, P < 0.05), but weight loss had no effect. In conclusion, exercise but not weight loss had a beneficial effect on markers of muscle inflammation and anabolism in frail obese elderly individuals.
- Growth factors
- Weight loss