The circadian rhythm is the inherent 24-hour clock that exists in every living thing and keeps us ticking. The circadian rhythm, which is triggered by light, keeps our body on schedule by preparing us for our waking and sleeping hours.
Scientists demonstrate how they can counteract the effects of aging and reset our circadian rhythm to a healthy speed by increasing NAD+ levels in a Molecular Cell publication.
The researchers discovered that NAD+ boosters altered almost 50% of the entire circadian rhythm-related genetic program in the livers of mice. The changed genes are required for the proper functioning of stress and metabolic networks. BMAL1– a master gene that promotes rhythmic gene activity and regulates biological processes via DNA binding– was one of the genes that drew the researchers’ attention.
As we age, a core clock suppressor called PER2 increases and decreases the activity of our circadian rhythms by suppressing BMAL1. The level of NAD+ governs the breakdown of PER2, which in turn stimulates the activity of BMAL1, maintaining a healthy internal clock. However, the amount of NAD+ in our bodies decreases as we age. Aging has been linked to a slowed and less robust circadian rhythm. In elderly mice, decreased NAD+ results in an increase in PER2, which suppresses circadian rhythms. By supplementing elderly mice with NAD+, the researchers found a significant decrease in PER2 and an increase in BMAL1 activity, reversing the age-related decline.
Circadian Rhythm And Aging
Circadian rhythm disruption in the early evening is one of the hallmarks of aging in humans. As we age, we get weary earlier, go to bed earlier, and wake up earlier. Old mice with regenerated NAD+ do not experience the early evening or late afternoon decline. Unlike other aged mice, the NAD+-boosted animals spend their time running on wheels, comparable to youthful mice. Replenishing NAD+ in older animals can prevent age-related molecular and circadian deterioration.
By inhibiting PER2, it may be possible to aid in the synchronization of the internal clocks of patients with shift work problems and neurodegenerative disease-associated sleep loss. Additionally, the researchers propose that increasing NAD+ levels may be a potential therapeutic technique for “improving age-related declines in behavior and metabolism.”