Leucine role in mitochondrial and muscle health

Research from the University of Cologne, published in Nature Cell Biology, has identified a mechanism by which the amino acid leucine supports muscle health and mitochondrial function. The studies indicate that leucine acts as a metabolic signal through the mTOR complex to trigger muscle protein synthesis, which is particularly relevant for combating sarcopenia in aging populations.

Further investigation into the leucine-GCN2-SEL1L axis reveals that leucine helps stabilize proteins on the outer membrane of mitochondria. By reducing the activity of the SEL1L protein—which typically functions as a quality control inspector for damaged proteins—leucine prevents the degradation of these proteins, thereby maintaining cellular respiration and energy production.

While these findings offer potential therapeutic strategies for metabolic disorders and aging, researchers noted that certain genetic modifications related to leucine metabolism appeared to favor tumor survival in human lung cancer cell lines. Additionally, studies using Caenorhabditis elegans demonstrated that altered leucine metabolism can lead to decreased mitochondrial performance and fertility defects.