In their study, the scientists compared mice with mild TBI to uninjured mice. They found that injured mice were much less able to stay awake for sustained periods of time. The scientists also found that the orexin neurons in the brains of injured mice were much less active than the same neurons in uninjured mice. Orexin neurons help to maintain wakefulness, in mice and in humans. Human studies have shown decreased orexin levels in the spinal fluid of people who have suffered a traumatic brain injury.
Based on prior research, the scientists gave the injured mice a dietary therapy of branched chain amino acids which humans get most often through foods high in protein, including red meat, poultry and eggs. Branched chain amino acids are the building blocks of neurotransmitters, the chemicals released by neurons in the brain. Like the oil in a car engine, branched chain amino acids keep neurons running smoothly and boost neuron excitability. The branched chain amino acids restored the orexin neurons in the injured mice to a normal activity level, and improved wakefulness.
"These results in an animal model provide a proof-of-principle for investigating this dietary intervention as a treatment for TBI patients," said Cohen. "If a dietary supplement can improve sleeping and waking patterns as well as cognitive problems, it could help brain-injured patients regain crucial functions."
The scientists note that human patients with a variety of disorders have been treated with branched chain amino acid therapy for up to two years without adverse effects, so with further study it may prove to be a viable therapy for sleep problems in TBI patien
|Contact: Todd Murphy|
Oregon Health & Science University