Despite strenuous controversies, the field of sirtuin research is growing with an increasing number of recent studies revealing their promising connection to longevity. After many years of investigation, understanding of the activity of the silent information regulator 2 (Sir2) family (‘sirtuins’) has greatly expanded, proving its significant involvement in the regulation of many fundamental biological processes. Dr. Leonard Guarente, co-founder of Elysium Health and director of MIT’s Glenn Center for Biology of Aging, stands at the forefront of sirtuin research efforts.
A recent DNA repair discovery could potentially lead to the creation of drugs that can reverse aging, fight cancer, and help assist in eliminating the effects radiation exposure. While it has long been known that DNA repair is essential for cell vitality, cell survival, and cancer prevention, the decline in cells’ ability to repair damaged DNA with age has not been fully understood.
A team of scientists at Harvard Medical School has identified a critical step in assessing how cells repair damaged DNA. Published in the journal Science, the international team’s study pinpointed a vitamin called NAD+, which regulated the interactions that control DNA repair. When mice were given an NAD+ booster called NMN, experiments indicated that their cells were more effective in repairing DNA damage caused by aging, and radiation exposure. The mice’s DNA repair activities markedly shifted to ‘youthful levels,’ and further trials demonstrated that they were more resistant to radiation; therefore, they were more protected against cancer and aging itself.
Human trials of NMN therapy will begin in Boston, in the next six months. One of the lead professors on the team from Harvard discussed the potential for evaluating how people walk, their strength, and ultimately transitioning the molecule to a substance on the drug market, in order to treat diseases like cancer, Alzheimer’s, and diabetes. The results further shed light on a possible therapy to avert the unwanted side effects of environmental radiation, by restoring NAD levels by NMN treatment—in addition to radiation exposure from cancer treatments.
White matter tracts enable communication between areas of the brain, but like the rest of the body, they decline with age. However, research suggests that staying active may help to preserve the integrity of these tracts. Agnieszka Burzynska, a postdoctoral researcher at the University of Illinois, and colleagues used accelerometers to track physical activity in 88 healthy but “low-fit” participants aged 60 to 78. Results showed that older adults who engaged more often in light physical activity had greater structural integrity in the white-matter tracts of the temporal lobes, which play a key role in memory, language, and the processing of visual and auditory information. Conversely, those who spent more time sitting had lower structural integrity in the white-matter tracts connecting the hippocampus. “This relationship between the integrity of tracts connecting the hippocampus and sedentariness is significant even when we control for age, gender and aerobic fitness,” said Burzynska. “It suggests that the physiological effect of sitting too much, even if you still exercise at the end of the day for half an hour, will have a detrimental effect on your brain.”
Burzynska AZ, Chaddock-Heyman L, Voss MW, et al. Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults. PLoS One. 2014 Sep 17;9(9):e107413. For more visit http://www.eurekalert.org/pub_releases/2014-09/uoia-slp091614.php