What Are Memories Made Of?

When thinking of memories, we conjure up childhood parties, weddings or maybe your child’s birth.  Charles Hoeffer, assistant professor of integrative physiology at CU Boulder has been working for 5 years to better understand a protein called AKT.  His answer would be, he thinks about proteins.  AKT is ubiquitous in brain tissue and instrumental in enabling the brain to adapt to new experiences to lay down new memories.

Scientists know very little about what it does to the brain, but there is now a new paper funded by the National Institutes of Health by Hoeffer and his co-authors.  They are showing that AKT comes in three distinct varieties residing in different kinds of brain cells and affecting our brain health in very distinct ways.  This could lead to new and more targeted treatments for everything from glioblastoma to Alzheimer’s disease and schizophrenia.

AKT is a central protein that has been implicated in many neurological diseases that we know little about.  This is the first comprehensive examine outlining what the different forms are doing in the brain and where.

Oncogene, one that can promote cancer when mutated was discovered in the 1970s,  AKT has recently been identified as a key player in promoting synaptic elasticity, which is the brain’s ability to strengthen cellular connections in response to experience.  When you see something that scares you, your brain wants to form a memory of it.  You make new proteins to encode that memory.  AKT is one of the first proteins to come online as a central switch that turns on the memory factory.  Not all AKTs are created equal.  AKT2 is found exclusively in astroglia, the star-shaped cells in the brain and spinal cord often impacted in brain cancer and injury.

If a drug could be developed that targeted only AKT2 without impacting other forms, it might be more effective in treating certain issues with fewer side-effects.  They also found that AKT1 is ubiquitous in neurons and appears to be the most important form in promoting the strengthening of synapses in response to memory formation.  AKT3 plays a key role in brain growth.

Pan-AKT inhibitors have been developed for cancer treatment, but they envision a day when drugs could be developed to target more specific versions of the protein, leaving the other forms untouched, preventing side-effects.  Animal research is currently underway to determine what happens to behavior when different forms of the protein go awry.  The brain’s immune system may be the key to better treatments for psychiatric disorders.

Dr Fredda Branyon