Study finds increased life span in mice supplemented with resveratrol
Friday, March 8, 2013. In an article published online on November 7, 2012 in the journal AGE, researchers in Barcelona, Spain report a life extension benefit for resveratrol, a polyphenol found in grapes, in a mouse model of Alzheimer's disease as well as in a group of normal mice. Resveratrol also reduced some of the signs of Alzheimer's disease in animals that received the compound.
The research team utilized an age-accelerated strain of mice (SAMP8) that exhibit memory and learning deficits as well as other neurologic impairments, in addition to such brain pathologies as increased amyloid beta levels and tau hyperphosphorylation. A related strain of animals (SAMR1) was used as a control group.
Beginning at two months of age, the mice were divided to receive a standard diet, or a diet supplemented with resveratrol. In SAMP8 mice fed a standard diet, the median life expectancy was 10.4 months in comparison with the SAMR1 group which survived a median of 17.8 months. However, in SAMP8 mice given resveratrol, median life expectancy increased to 14 months, and SAMR1 mice that received the compound experienced a median life span of 21.8 months. Maximum life span, determined by the longest-lived 20 percent of animals in each group, was also greater in animals that received resveratrol. Analysis of the animals' brains revealed higher levels of SIRT1, a protein activated during calorie restriction, in the resveratrol-fed groups.
To study resveratrol's effect on neurodegeneration, SAMP8 mice were examined after seven months of a standard or resveratrol-enhanced diet. In addition to less memory impairment, animals that received resveratrol had reduced amyloid beta accumulation and phosphorylated tau in comparison with those that did not receive the compound.
"We found that resveratrol supplements increased mean life expectancy and maximal life span in SAMP8 and in their control, the related strain SAMR1," David Porquet and his coauthors write. "It also reduces cognitive impairment and has a neuroprotective role, decreasing the amyloid burden and reducing tau hyperphosphorylation."
They recommend further studies in order to clarify resveratrol's role in life span extension.