Zapping the brain with electrical current could prevent dementia symptoms for up to 20 years before they start, a study in mice suggests.
Researchers in Tel Iviv, Israel, found that they could halt the decay of brain cells and prevent memory loss and cognitive decline if they targeted the areas of rodents’ brains damaged during Alzheimer’s disease.
Using electrodes surgically attached to their brains, the team delivered low-level electrical waves to prevent harmful proteins from forming in the brain and the brain’s memory center from shrinking.
They found that the electrical currents prevented deterioration that could be a sign of Alzheimer’s disease, which they believed had been happening in humans for 10 to 20 years before diagnosis.
Alzheimer’s disease is the most common form of dementia, an umbrella term used to describe a range of progressive neurological conditions that affect memory, thinking and behavior. According to the Alzheimer’s Association, more than six million Americans have the condition and 73 percent are 75 or older
Study author Dr Inna Slutsky said: ‘This indicates a potential for predicting the disease in the dormant state, before the onset of cognitive decline.’
The team analyzed changes in the brain that occur during sleep, which they say is often when the first signs of the condition develop.
To test this, the researchers put the mice to sleep under anesthesia to study changes in the hippocampus, the memory center of the brain.
The team used anesthesia based on data suggesting that anesthetics can lead to a buildup of toxic proteins that can lead to Alzheimer’s disease.
Study author Dr. Inna Slutsky said these signs of decline can occur years before symptoms of dementia. “Anesthesia reveals a pathophysiology in brain activity in the animal model,” she said.
‘We think there are mechanisms that compensate for the same pathology while awake and thus prolong the pre-symptomatic period of the disease.’
The researchers found that the mice experienced “silent seizures” in the hippocampus while sleeping, which look like seizures on brain scans but don’t cause any outward symptoms. However, healthy mice had reduced activity.
They said the silent seizures could be signs that the brain is deteriorating.
To prevent this excessive activity, the team used deep brain stimulation (DBS), a surgical procedure in which electrodes are placed in specific parts of the brain. These electrodes are connected via wires to a device that is placed under the skin near the chest.
The device sends electrical pulses whenever the brain produces abnormal signals, such as signals that result in memory problems, balance problems and speech problems.
The team noted that patients with Alzheimer’s disease show several signs of deterioration in their brains. This includes the build-up of the proteins amyloid beta and tau, which can destroy brain cells responsible for memory.
In addition, the memory and learning center of the brain – the hippocampus – shrinks and there is increased activity during sleep. This leads to memory loss.
The researchers focused on finding protective measures against this decline.
Shiri Shoob, lead author of the study and PhD candidate at Tel Aviv University, said: ‘For ten to twenty years before the appearance of the well-known symptoms of memory impairment and cognitive decline, physiological changes are slowly and gradually occurring in the brain of the elderly. patient. .’
In the study, published in November in the journal Nature communicationMs. Shoob’s team found that DBS suppressed that excessive activity, preventing cognitive decline for 20 years before the onset of Alzheimer’s disease.
In the study, researchers connected the electrodes to the nucleus reuniens, a small part of the brain that connects the hippocampus to the thalamus, which regulates sleep. It is unclear how often the mice were provided with electrical impulses.
DBS is also used in the US to treat neurological disorders such as Parkinson’s disease, epilepsy, essential tremor, dystonia and obsessive-compulsive disorder.
“When we tried to stimulate the nucleus reuniens at high frequencies, as is done for example in the treatment of Parkinson’s, we found that this worsened hippocampal damage and silent seizures,” said Ms Shoob.
‘Only after we changed the stimulation pattern to a lower frequency were we able to suppress the seizures and prevent cognitive impairment.’
‘We showed that the nucleus reuniens had the ability to fully control these seizures. By stimulating it we can increase or decrease the attacks.’
The team plans to conduct human clinical trials next.
Alzheimer’s disease is the most common form of dementia, an umbrella term used to describe a range of progressive neurological conditions (affecting the brain) that affect memory, thinking and behavior.
Common symptoms include memory loss, poor judgment, confusion, repetitive questions, communication problems, taking longer to complete normal daily tasks, acting impulsively and mobility problems.
According to the Alzheimer’s Association, more than six million Americans suffer from the condition and 73 percent are 75 years or older.