临床营养与代谢杂志

Traumatic Brain Injury and Branched-Chain Amino Acids

 João Luís Pinheiro, Armando Rocha and João Pinheiro

Introduction: Traumatic brain injury is a major cause of death and disability in the youth population. It is not a common injury in sports practice but it is more frequent in modalities involving high energy movements at the cranial and cervical spine levels. Its neurological consequences can be serious, such as motor deficits and changes in the learning process and memory. This article discusses the role of branched-chain amino acids in improving cognitive functions after traumatic brain injury.

Methods: We conducted a literature search in PubMed / Medline, PEDro and Cochrane, up to 2016 with no limit on the starting date. Additional search were performed on other editors.

Results: A total of 23 articles were reviewed and various clinical elements were extracted to meet the objectives proposed.

Discussion and conclusion: After traumatic brain injury there is a decrease in the level of branched-chain amino acids in the central nervous system as well as an imbalance between excitatory and inhibitory potentials in the dentate gyrus in the cornu ammonis (CA) 1 and 3, with consequent impairment of neurocognitive functions. They are neurotransmitter precursors responsible for the balance of the hippocampal synaptic network. They are vital elements in metabolic reactions essential for neurotransmitters formation, and the cohesion of the synaptic network.

Human studies have demonstrated its efficacy in improving cognitive functions after traumatic brain injury. The impact of these amino acids may also be developed for other sequelae resulting from traumatic brain injuries, namely motor or sleep disorders.