Better diet and brain glucose uptake lead to longer life in fruit flies

Tokyo, Japan – Researchers from Tokyo Metropolitan University have found that fruit flies have a much longer lifespan with genetic modifications to increase glucose uptake. Looking at the brain cells of aging flies, they found that improved glucose uptake compensates for age-related decline in motor functions, leading to longer life . The effect was more pronounced when combined with dietary restriction. This suggests that healthier eating and better brain glucose uptake may lead to a better life.

The brain is a special part of the energy of our bodies, consuming 20% ​​of the oxygen we absorb and 25% of the glucose. That’s why it’s so important to be able to stay energized, using glucose to make adenosine triphosphate (ATP), the body’s “energy messenger”. This chemical process, called glycolysis, occurs both in the intracellular stream and in part of cells called the mitochondria. But as we get older, our brain cells will be less able to make ATP, something that is largely linked to less glucose. Maybe that suggests that more food for more glucose may be a good thing. On the other hand, a healthier diet is known to lead to a longer life. Unraveling the mystery surrounding the two opposing pieces of information could lead to a better understanding of healthier and longer-term lifestyles.

A team led by Professional Professor Kanae Ando investigated this problem using Drosophila fruit flies. First, they found that older flies had lower brain levels of ATP in brain cells, and less glucose. These were specifically linked to lower levels of the enzymes required for glycolysis. To counteract this effect, they genetically modified flies to produce more glucose-carrying proteins called hGut3. Surprisingly, this increase in glucose uptake was all that was needed to significantly improve the amount of ATP in cells. In particular, they found that increased hGut3 led to a lesser decrease in enzyme production, reversing the decline with age. While this did not cause an improvement in age-related damage to mitochondria, they also suffered less of a decline in locomotor functions.

But that’s not it. In another version, the team placed the flies with improved glucose uptake under dietary restrictions, to see how the effects interact. Now, the flies had a longer life. Ironically, an increase in glucose did not improve glucose levels in brain cells. The results highlight the importance of not only the level of glucose, but how effective it is once it is absorbed into cells to convert the energy. which the brain needs to do.

While the anti-aging benefits of a restricted diet have been demonstrated in many species, this team was able to combine it with improved glucose uptake to reap both benefits for even life expectancy. longer in an organism model. Further study may provide important evidence on how we can keep our brains healthier for longer.

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This work was supported by a research award from the Japan Foundation for Aging and Health, JSPS KAKENHI Grant-In-Aid for Scientific Research on Challenge Research (Study) (19K21593), NIG-JOINT (71A2018, 25A2019), Grant-in-Aid for JSPS Research Fellows (18J21936) and Research Funding for Lifelong Science (19-7) from the National Center for Geriatrics and Gerontology, Japan.