Can Cod Protein Improve Skeletal Muscle Repair Following Injury?

It has been recently shown that cod protein can modulate the production of pro‐inflammatory cytokines. We therefore postulated that it may regulate muscle regeneration and promote muscle mass recovery. The aim of this study was to determine the effects of dietary cod protein on skeletal muscle repair after injury compared with casein. Sixty four male Wistar rats were assigned to isoenergetic diets composed of either dietary cod protein or casein. After 21 d of ad libitum feeding, one tibialis anterior muscle (TA) was injured by bupivacaine injection (100μl) at the half proximal region while the contra‐lateral TA was injected with saline and served as sham. TA muscles collected at time 0 served as control. At day 14 post‐injury, values for muscle weight in both contra‐lateral (0.017) and injured groups (0.014) were higher in rats fed the cod protein diet, indicating better muscle mass recovery than in those fed the casein diet. Conversely, the cod protein diet led to lower pro‐inflammatory ED1+ macrophage density in both injured (P=0.008) and contra‐lateral sham (P=0.029) at day 24 post‐injury, suggesting that cod protein modulates the time course of inflammatory cell trafficking. Globally these data suggest that cod protein favors muscle growth and influences the inflammatory response, which potentially impact on recovery following injury. Supported by The Natural Sciences and Engineering Research Council of Canada.