Lower basal and postprandial muscle protein synthesis after 2 weeks single‐leg immobilization in older men: No protective effect of anti‐inflammatory medication

Abstract

Abstract Muscle inactivity may reduce basal and postprandial muscle protein synthesis (MPS) rates in humans. Anti‐inflammatory treatment alleviates the MPS impairments in younger individuals. The present study explored the influence of nonsteroidal anti‐inflammatory drugs (NSAIDs) upon MPS during a period of inactivity in older humans. Eighteen men (age 60–80 years) were allocated to ibuprofen (1200 mg/day, Ibu) or control (Plc) groups. One lower limb was cast immobilized for 2 weeks. Postabsorptive and postprandial MPS was measured before and after the immobilization by L‐[ring‐13C6]‐phenylalanine infusion. The protein expression of select anabolic signaling molecules was investigated by western blot. Basal (0.038 ± 0.002%/h and 0.039 ± 0.005%/h, Plc and Ibu, respectively) and postprandial (0.064 ± 0.004%/h and 0.067 ± 0.010%/h, Plc and Ibu, respectively) MPS rate were higher pre‐immobilization compared to basal (0.019 ± 0.005%/h and 0.020 ± 0.010%/h, Plc and Ibu, respectively) and postprandial (0.033 ± 0.005%/h and 0.037 ± 0.006%/h, Plc and Ibu, respectively) MPS rate post‐immobilization (p 0.05). The anabolic signaling were in general reduced after immobilization (p 0.05). Basal and postprandial MPS dropped markedly after 2 weeks of lower limb immobilization. NSAID treatment neither influenced the reduction in MPS nor the anabolic signaling after immobilization in healthy older individuals.

Keywords

• anabolic resistance
• ibuprofen
• muscle disuse
• muscle inactivity
• muscle protein synthesis signaling
• myofibrillar FSR