5.23.2013
Caloric Restriction in Mice Preserves Cognitive Function
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Activating an enzyme known to play a role in the anti-aging benefits of calorie restriction delays the loss of brain cells and preserves cognitive function in mice, a new study has found.
The findings could one day guide researchers to discover drug alternatives that slow the progress of age-associated impairments in the brain.
Previous studies have shown that reducing calorie consumption extends the lifespan of a variety of species and decreases the brain changes that often accompany aging and neurodegenerative diseasessuch as Alzheimer's.
There is also evidence that caloric restriction activates an enzyme called Sirtuin 1 (SIRT1), which studies suggest offers some protection against age-associated impairments in the brain.
In the current study, Li-Huei Tsai, PhD, Johannes Graff, PhD, and others at the Picower Institute For Learning and Memory, Massachusetts Institute of Technology, and Howard Hughes Medical Institute, tested whether reducing caloric intake would delay the onset of nerve cell loss that is common in neurodegenerative disease, and if so, whether SIRT1 activation was driving this effect.
The group not only confirmed that caloric restriction delays nerve cell loss, but also found that a drug that activates SIRT1 produces the same effects.
"There has been great interest in finding compounds that mimic the benefits of caloric restriction that could be used to delay the onset of age-associated problems and/or diseases," Luigi Puglielli, MD, PhD, who studies aging at the University of Wisconsin, Madison, and was not involved in this study, said.
"If proven safe for humans, this study suggests such a drug could be used as a preventive tool to delay the onset of neurodegeneration associated with several diseases that affect the aging brain," Puglielli added.
In the study, Tsai's team first decreased by 30 percent the normal diets of mice genetically engineered to rapidly undergo changes in the brain associated with neurodegeneration.
Following three months on the diet, the mice completed several learning and memory tests.
"We not only observed a delay in the onset of neurodegeneration in the calorie-restricted mice, but the animals were spared the learning and memory deficits of mice that did not consume reduced-calorie diets," Tsai said.
The study is published in The Journal of Neuroscience. (ANI)
Labels: howard-hughes-medical-institute, johannes-graff, li-huei-tsai, MIT, picower-institute, sirt1