Figure 7.

Endocrine regulation of feeding behavior by myokine signaling. Dpp is an endocrine myokine that signals to the brain. In skeletal muscle, dpp expression is induced by nutrient sensing (mTOR signaling). Consistently, muscle-restricted dpp RNAi leads to higher pale/tyrosine hydroxylase (TH) expression in the brain and higher chance of foraging and feeding initiation, whereas muscle-restricted dpp overexpression elicits converse effects. Cell-autonomous decrease of Dpp receptor signaling in dopaminergic neurons leads to higher ple/TH expression and higher propensity for feeding initiation. These results highlight a muscle-to-brain signaling axis that regulates feeding behavior.