The role of leucine in the activation of cellular metabolism: a large integrative review

Abstract

This review addressed the signaling of cellular activation by leucine, discussed the risks of excessive signaling by proteins in the Western diet, and explored the potential of leucine stimulation in tissue regeneration. As result, amino acids are, in addition to building blocks of macromolecules, cellular activation signals. Essential amino acids are not produced by animals and leucine appears to be the main signaling amino acid. Mammals adjusted the cell activation and growth rate of their young by the leucine concentration of the milk produced. Several studies demonstrate the benefits of leucine supplementation in preventing sarcopenia, improving muscle and liver performance, as well as a possible neuroprotective role in head trauma and dementia. However, its excess, so common in the Western diet, is related to obesity, type II diabetes, neurodegenerative diseases, and cancer. The mTORC1 kinase integrates cellular activation stimuli from macro protein synthesis to epigenetic regulation. Controlling mTORC1 activity by consuming leucine can prevent, treat, or cause disease. A greater understanding of the regulatory effects of leucine and mTOR in unstable tissues such as tumors or fragile tissues such as the CNS are areas of great relevance and with extensive fields still to be explored.