Schematic summary of findings. Leucine supplementation promotes hepatic cell glucose uptake by upregulating solute carrier family member2 (SLC2A2) expression via myostatin (MSTN). MSTN activity leads to the activation of AMP- activated protein kinase (AMPK) and inhibition of glycogen synthesis. Furthermore, activation of MSTN leads to overexpression of genes involved in glucose uptake, which is further responsible for triglyceride synthesis. Moreover, leucine supplementation alters the expression of several small RNA species including miR-143, miR-335 and miR-92b*, which target main gene regulators of these effects.