New target to prevent Alzheimer’s patients forgetting loved ones: Loss of social memory – recognizing friends and family – in Alzheimer’s could come down to specific structures around brain cells. When scientists kept these intact using existing drugs, mice were able to recognize familiar animals.

New target to prevent Alzheimer’s patients forgetting loved ones

New research has found that the loss of social memory – recognizing friends and family – in Alzheimer’s disease (AD) could come down to specific structures around brain cells. And targeting this delicate scaffolding may potentially prevent this heartbreaking stage in cognitive decline.

Sontheimer and team believed that disruptions in these perineural nets, which protect communicating nerve cells, result in the neurons being unable to form and store memories. While perineuronal nets were first discovered back in 1898 by Camillo Golgi, the UVA scientists believe these structures are a lot more important to our brain’s health than previously thought. These nets surround inhibitory neurons, which play a key role in regulating brain activity, slowing down the signals transmitted by excitatory nerve cells.

When the nets are damaged through AD, specialized support cells (astrocytes) cease being able to remove potassium or glutamate from the synapse that connects the neurons, which then causes glutamate to “spill over” into regions it shouldn’t be, potentially killing off neighboring neurons.

In a mouse model, the researchers found that damaged perineural nets resulted in the animals losing their “social memory,” unable to recognize mice they were familiar with – even though other parts of their memory and object recognition was intact. This is, of course, something that occurs as AD progresses, where patients can fail to identify loved ones yet retain “object memory” for some time. When the scientists kept the perineural nets intact, mice were able to recognize familiar animals.

The team used matrix metalloproteinase (MMP) inhibitors – which are predominantly being investigated in cancer research – to block the AD-driven damage to perineural nets in mice, and the treatment halted their destruction. While still early days, these existing drugs could be an entirely new way to protect the brain as the disease progresses.

For those interested, here’s the link to the peer reviewed journal article:

https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/alz.70813