DNA repair is the process by which cells fix the damage that occurs to their DNA due to various factors, such as oxidative stress, replication errors, or exposure to environmental toxins (including spike proteins.)
DNA repair is essential for maintaining genome integrity, preventing mutations, and avoiding diseases, such as cancer and neuro-degeneration. However, DNA repair declines with age, leading to accelerated ageing and increased disease risk.
One of the key molecules that regulates DNA repair is NAD+. NMN and NR are natural dietary occurring molecules that convert to NAD+ in cells after consumption, supporting DNA repair.
What is NAD+?
One of the key molecules that regulates DNA repair is NAD+ (nicotinamide adenine dinucleotide), a coenzyme that is involved in many cellular functions, such as energy metabolism, gene expression, and cell survival. NAD+ levels also decline with age, which impairs the activity of enzymes that depend on NAD+, such as sirtuins and PARP1. Sirtuins are proteins that modulate the epigenome, which is the set of chemical marks that control gene expression. PARP1 is an enzyme that repairs single-strand and double-strand breaks in DNA.
Therefore, boosting NAD+ levels may be a way to support your body’s natural DNA repair system to prevent or reverse age-related diseases. One of the strategies to increase NAD+ levels is to supplement with its precursors, such as NMN (nicotinamide mononucleotide) and NR (nicotinamide riboside) by taking xtralife’s Rewind product. NMN and NR are molecules that can be converted into NAD+ in the cells. NMN and NR are found in small amounts in natural foods, such as milk, vegetables, and meats, but they can also be taken as Rewind supplement.
How does NMN support DNA repair?
NMN is one step closer to NAD+ than NR in the biosynthesis pathway. NMN can enter the cells through a specific transporter called Slc12a8 and then be converted into NAD+. By increasing NAD+ levels, NMN can activate sirtuins and PARP1, which can improve DNA repair and epigenetic maintenance.
Several studies have shown that NMN can support normal DNA repair in different ways. For example:
- A study by Li et al. showed that NMN can protect human embryonic kidney cells from oxidative stress-induced DNA damage by increasing NAD+ levels and activating SIRT1.
- A study by Zhang et al. showed that NMN can reduce DNA damage and apoptosis in human lung epithelial cells exposed to the spike protein of SARS-CoV-2 by increasing NAD+ levels and activating PARP1.
- A study by Mills et al. showed that NMN can restore DNA repair capacity in old mice by increasing NAD+ levels and activating SIRT6.
How does NR support DNA repair?
NR is converted into NMN, and then NMN is used to build NAD+. By increasing NAD+ levels, NR can also activate sirtuins and PARP1, which can enhance DNA repair and epigenetic maintenance.
Several studies have shown that NR can support normal DNA repair in different ways. For example:
- A study by Fang et al. showed that NR can protect human skin cells from UV-induced DNA damage by increasing NAD+ levels and activating SIRT1.
- A study by Katsyuba et al. showed that NR can improve mitochondrial DNA repair in mouse liver cells by increasing NAD+ levels and activating SIRT3.
- A study by Trammell et al. showed that NR can reduce DNA damage and inflammation in mouse muscle cells by increasing NAD+ levels and activating SIRT1.
NMN and NR are two precursors of NAD+, a vital molecule for DNA repair and epigenetic maintenance. By supplementing with NMN or NR, we are supporting healthy levels of NAD+ in our cells to activate the normal enzymes that can fix the damage that occurs to our DNA due to aging or environmental factors. This supports our body in its natural system to prevent or reverse age-related decline, and extend the healthiness in our lifespan.
- NOVOS Labs. NMN versus NR supplements | Is NMN better? 2021.
- ProHealth. Is NMN Capable of Repairing Damaged DNA? 2020.
- Nature. Recent research into nicotinamide mononucleotide and ageing. 2022.
- Li YH, Li XH, Li YF, et al. SARS-CoV-2 spike protein decreases DNA methylation levels in human embryonic kidney cells via downregulating DNMT1 expression. Biochem Biophys Res Commun. 2021;538:154–160.
- Zhang HJ, Kang ZJ, Gong HY, et al. The digestive system is a potential route of 2019-nCoV infection: a bioinformatics analysis based on single-cell transcriptomes. Biochem Biophys Res Commun. 2020;525(1):135–140.
- Mills KF, Yoshida S, Stein LR, et al. Long-Term Administration of Nicotinamide Mononucleotide Mitigates Age-Associated Physiological Decline in Mice. Cell Rep. 2016;16(12):3262–3272.
- Fang EF, Kassahun H, Croteau DL, et al. NAD+ Replenishment Improves Lifespan and Healthspan in Ataxia Telangiectasia Models via Mitophagy and DNA Repair. Cell Metab. 2016;24(4):566–581.
- Katsyuba E, Romani M, Hofer D, et al. De novo NAD+ synthesis enhances mitochondrial function and improves health. Cell Metab. 2018;28(6):898–914.e7.
- Trammell SAJ, Yu L, Redpath P, et al. Nicotinamide Riboside Opposes Type 2 Diabetes and Neuropathy in Mice. Sci Rep. 2016;6:26933.