DNA Methyltransferase (DNMT) Could Reduce PTSD & Anxiety, and Boost Memory

Researchers at the Interdisciplinary Center for Neurosciences of Heidelberg University are working on the possibility of creating epigenetic therapies to decrease or eliminate traumatic memories and/or improve cognitive ability.

In the recent past, scientists have discovered immune-suppressing drugs that may inhibit HDACs - Histone deacetylase inhibitors - in order to stop bad memories. HDAC inhibitors – HDACi - HDIs are chemicals that decrease histone deacetylase, and have been used in neurology as anti-epileptics and in psychiatry to stabilize moods. In addition, studies show that histone acetylation might play a role in memory plasticity.

DNA Methyltransferase is an epigenetic enzyme that shows promise in reducing anxiety and PTSD – Post Traumatic Stress disorder by erasing harsh memories. In addition, it may improve learning, long-term memory, and cognition thereby helping patients with Alzheimer’s disease.

DNA methyltransferases are critical components in the epigenetic DNA methylation modification, which changes genetic expression without changing the genetic sequence. Professor Hilmar Bading, Ph.D and his team focused research on the epigenetics of DNA methylation and found that a key DNA methyltransferase (DNMT) known as DNMT3A2 may significantly improve cognitive ability, memory formation, and harsh memory extinction.

In previous studies, the Heidelberg researchers looked at the brains of older mice and found decreased levels of DNMT3A2 protein. However, when injected with a virus that increased production of the DNMT3A2 protein their memories were increased. Similarly, they found a boost in the memories of younger mice when injected; creating an over-expression in the hippocampus. The excess DNA methyltransferase improved memory formation, improved plasticity, and reduced fear based or bad memories.

DNMTs are enzymes that add a methyl group to DNA using SAM - S-adenosyl methionine as the methyl donor. DNMT3A2 can methylate cytosines. Alternatively, some DNA methyltransferases add a methyl group to DNA to maintain methylation when some strands are already methylated. Epigenetically DNA modification can be facilitated by DNMT3A2 to synthesize the proteins needed to consolidate or eliminate memories.

The researchers likened the outcomes of this type of therapy with conventional confrontational therapy used to disrupt disturbing associations with PTSD patients. They felt that the mice with higher brain levels of DNMT3A2 had a greater ability to do away with painful memories.

While still at an early stage, it appears the information in these studies strongly indicates that DNA methyltransferases may be a key to creating new drugs capable of treating cognitive decline and impaired memory as is commonly seen in anxiety, Alzheimer’s or senile dementia.  

Interestingly, the lead researcher Professor Bading felt that development of this type of drug might also lead to misuse in healthy people to improve mental abilities. More research, tests and trials are needed before safely releasing any new drug of this type to the marketplace