Previous studies have suggested that sharply reducing calorie intake, by as much as 40% could slow aging in cells and may even prolong life span. Now, researchers say they have found a way to mimic the beneficial effects of calorie restriction on the brain with a drug.
The pill can activate an enzyme in brain cells, and the study showed the drug delayed both the cognitive impairment associated with aging and Alzheimer’s disease, and the loss of nerve cells that happens with ageing, ‘MyHealthNewsDaily’ reported. The new study done in mice suggests scientists could develop drugs that stave off decline in human brain function.
Researchers at the Massachusetts Institute of Technology focused on how calorie restriction affects brain cells. They showed that restricting the calorie intake of laboratory mice by 30% boosted levels of an enzyme in the brain, and delayed the loss of nerve cells that can accompany decline in brain function. The calorie-deprived mice also did better on memory tests, compared with their well-fed counterparts.
Researchers fed the mice a regular diet, but also gave them the enzyme-blocking drug.
These mice had better functioning brain cells, and did better on cognitive tests, just as the mice that were fed a calorie-restricted diet.
A ‘brain switch’ for changing behaviour found
Researchers have discovered a potential “switch” in the human brain which prompts us to change our behaviour instantly as per the situation. Investigators at the University of Michigan and Eli Lilly measured levels of a neurotransmitter called acetylcholine, which is involved in attention and memory, while rats monitored a screen for a signal.
At the end of each trial, the rat had to indicate if a signal had occurred. Researchers noticed that if a signal occurred after a long period of monitoring or “non-signal” processing, there was a spike in acetylcholine in the rat’s right prefrontal cortex. No such spike occurred for another signal occurring shortly afterwards.
“In other words, the increase in acetylcholine seemed to activate or ‘switch on’ the response to the signal, and to be unnecessary if that response was already activated,” said Cindy Lustig, one of the study’s senior authors.
Researchers repeated the study in humans using functional magnetic resonance imaging (fMRI), which measures brain activity, and also found a short increase in right prefrontal cortex activity for the first signal in a series. To connect the findings between rats and humans, they measured changes in oxygen levels, similar to the changes that produce the fMRI signal, in the brains of rats performing the task.