Cranberry supplementation reduces accumulated oxidative damage
Many nutraceuticals and pharmaceuticals have been shown to promote health span and lifespan. However, the mechanisms underlying the beneficial effects of prolongevity interventions and the time points at which interventions should be implemented to achieve beneficial effects are not well characterized, report researchers of this new study.
In this new study Dr. Yaning Sun, PhD, Visiting Fellow, Functional Genomics Unit, of the National Institute on Aging and lead author along with colleagues examined the mechanism underlying lifespan extension induced by cranberry and the effects of short-term or life stage-specific interventions with cranberry on lifespan in Drosophila. Drosophila, a type of fruit flies widely used for biological research in studies of genetics, physiology, microbial pathogenesis and life history evolution.
For the study, researchers placed 100 to 200 flies in separate vials and fed the flies a high sugar diet supplemented with cranberry extract during the flies three biological stages; health span (3 to 30 days), transition span (31–60 days) and senescence span (61 days to the end when all flies died). In humans these stages are related to young adulthood, middle age and old age. Control flies did not receive the extract.
All flies were placed in new vials between the biological stages and recorded the number of dead flies at each transfer until all flies were expired.
The results showed that lifespan extension induced by cranberry was associated with reduced phosphorylation of ERK, a component of oxidative stress response MAPK signaling, and slightly increased phosphorylation of AKT, a component of insulin-like signaling. Lifespan extension was also associated with a reduced level of 4-hydroxynonenal protein adducts, a biomarker of lipid oxidation. Moreover, lifespan extension induced by cranberry was partially suppressed by knockdown of SOD2, a major mitochondrial superoxide scavenger.
Flies during the health span who received cranberry supplementation had a 25% longer life span compared to the control group.
Flies in the transition and senescence phases who received the supplementation had a 30% longer life span compared to the control group.
In their conclusion the researchers write “Cranberry supplementation during any of these life stages extended the remaining lifespan relative to the non-supplemented and life stage-matched controls. These findings suggest that cranberry supplementation is sufficient to promote longevity when implemented during any life stage, likely through reducing oxidative damage.”
According to Dr. Sun “The long-lasting effect of cranberry supplementation is probably due to its ability to change signaling pathways and epigenetic status.” “Our findings suggest that cranberry as an abundant and popular fruit is a potentially viable option for aging interventions in humans of different ages.”
“The complex nature of life stages poses a major challenge to develop effective interventions for promoting health span and lifespan,” write the researchers.
The team concludes “To our knowledge, cranberry is the first case showing that a pharmaceutical or nutraceutical can promote longevity when administered during any of the three distinct life stages.” “Future studies are warranted to determine how cranberry extends lifespan during different life stages. Such studies are important because different mechanisms may be involved during different life stages.”
This study appears in the February 2014 edition of Experimental Gerontology.