Figure 7. Schematic representation of the exercise- and PGC-1α-induced cross-talk between muscle and macrophages.

PGC-1α increases BNP expression by co-activating ERRα and/or AP1. BNP subsequently induces a chemokine cocktail in muscle fibers, and activates macrophages in a local, paracrine manner, which then may contribute to the enhanced repair and regeneration potential of trained muscles.