A combination of two natural nutritional supplements, vitamin A and methyl donor S-adenosylmethionine (SAM), can treat Post-Traumatic Stress Disorder (PTSD) in mice. The corresponding study was published in Molecular Psychiatry by researchers from Bar-Ilan University in Israel and McGill University in Canada.
PTSD is an incapacitating mental disorder that occurs following traumatic events. Research from the last two decades has found that our experiences, including those that are traumatic, may produce epigenetically modify our genes, making them work differently than before. These changes may 'embed' PTSD-like patterns in the brain and nervous system, which go on to present as PTSD.
In the current study, researchers sought to find whether epigenetic changes that occur following trauma cause PTSD. To do so, they studied mapped epigenetic DNA methylation marks in the nucleus accumbens, a part of the brain important for PTSD that plays a key role in reward and motivation, in animal models.
They found that the brains of animals exposed to trauma that did not develop PTSD-like behavior were markedly different from those exposed to trauma that did develop the condition.
Further examination found that animals more susceptible to PTSD had lower levels of DNMT3A, an epigenetic enzyme that transfers methyl groups onto DNA. They also found that one group of genes altered by PTSD is controlled by the retinoic acid receptor, which is activated by vitamin A.
Later experiments found that delivering DNMT3A and retinoic acid orphan receptor genes into animals' brains reverses PTSD-like symptoms. However, as injecting these genes into the brain is not feasible for therapy, the authors also tested whether nutritional supplements that mimic the activity of these genes could have similar effects.
To do so, they administered methyl donor SAM, a natural product that donates methyl groups, alongside vitamin A to animals models of PTSD. Both supplements, when used together, reversed PTSD-like behaviors.
"Since these nutritional supplements are relatively nontoxic, they offer hope for a nontoxic treatment of PTSD that reverses the underlying genomic cause of the disease," said Gal Yadid, lead author of the study.