Memory loss in animal brain cells reversed

Scientists have reversed memory loss in sea snail nerve cells - a breakthrough that may lead to treatments for nuero-degenerative brain diseases like Alzheimer's in humans.
Using sea snail nerve cells, neuroscientists at The University of Texas Health Science Center at Houston (UTHealth) reversed memory loss by determining when the cells were primed for learning.
They were able to help the cells compensate for memory loss by retraining them through the use of optimised training schedules.
"Although much works remains to be done, we have demonstrated the feasibility of our new strategy to help overcome memory deficits," said John "Jack" Byrne, the study's senior author, as well as director of the WM Keck Center for the Neurobiology of Learning and Memory.

Yili Zhang, the study's co-lead author, developed a sophisticated mathematical model that can predict when the biochemical processes in the snail's brain are primed for learning.
Her model is based on five training sessions scheduled at different time intervals ranging from 5 to 50 minutes. It can generate 10,000 different schedules and identify the schedule most attuned to optimum learning.

"The logical follow-up question was whether you could use the same strategy to overcome a deficit in memory," Byrne said in a statement.
"Memory is due to a change in the strength of the connections among neurons. In many diseases associated with memory deficits, the change is blocked," Byrne said.

To test whether their strategy would help with memory loss, Rong-Yu Liu, co-lead author, simulated a brain disorder in a cell culture by taking sensory cells from the sea snails and blocking the activity of a gene that produces a memory protein.
This resulted in a significant impairment in the strength of the neurons' connections, which is responsible for long-term memory.
To mimic training sessions, cells were administered a chemical at intervals prescribed by the mathematical model. After five training sessions, which like the earlier study were at irregular intervals, the strength of the connections returned to near normal in the impaired cells.

"This methodology may apply to humans if we can identify the same biochemical processes in humans. Our results suggest a new strategy for treatments of cognitive impairment. Mathematical models might help design therapies that optimise the combination of training protocols with traditional drug treatments," Byrne said.
The study was published in The Journal of Neuroscience.