Scientists have discovered a way to counteract the effects of aging in mice: the study shows how a protein, present in abundant quantities in young mice, plays a vital role in keeping them healthy.
The decline in the levels of this protein also corresponds to the progressive drop in subjects: vision problems, cognitive decline, weight gain, insulin resistance.
Providing doses of this protein to elderly specimens slowed the decay of function and lengthened their survival by 16%.
As reported in the journal Cell Metabolism, the protein circulating in mice (an enzyme called eNAMPT) plays a key role in the process that provides cells with energy. Over the years, the latter they become less and less efficient in the production of this "fuel" (called NAD) necessary for his health.
By integrating eNAMPT into the diet of older mice, NAD production is maintained at good levels and aging is put on hold.
More activities, more quality sleep
“We have identified a completely new path against aging,” says the study author, Shin-ichiro Imai, professor of developmental biology at Washington University in St. Louis. “Taking the eNAMPT protein from the blood of younger mice and providing it to older mice has seen great benefits, including more intense physical activity and better sleep quality: even the hair shines like that of young people again.”
Research supported by the National Institute on Aging, the American Federation for Aging Research, and the Tanaka Fund shows also differences of sex in protein levels, with specimens very female most equipped with eNAMPT.
Unlike studies involving blood transfusions, transfer only one component considerably improves the processes: another element capable of increasing NAD in tissues of the body it is a molecule, called NMN, to be administered orally. NMN is already at a later stage and has been tested on humans for a few months.
“We believe the body has many systems for maintaining good levels of NAD, which is important in regulating how long and how healthy we live,” says Imai. “In worms, fruit flies, mice and humans, the presence of NAD is fundamental and decreases over the years.”
eNAMPT in action
Imai's research shows that the hypothalamus exerts the greater control on aging processes through the management of eNAMPT, which is released into the blood through fatty tissues. The hypothalamus manages processes vital as body temperature, sleep and circadian cycle, hormone levels and even thirst.
Tiny particles, so-called extracellular vesicles carry eNAMPT in the blood: eNAMPT levels decline in parallel with the decline of the hypothalamus, and reduce away time away of survival of a subject. Simply, in the mouse study, more eNAMPT means more days of life, less eNAMPT means fewer days to live: 1029 days against 881, to be precise.
"We can even predict a guy's lifespan based on his circulating eNAMPT levels," explains Imai. “We don't know how strong this link is in humans, but it is certain that human extracellular vesicles also transport the protein: the phenomenon needs to be studied.”