The ability to repair DNA damage decreases over time, causing an accumulation of mutations that can affect cellular function, viability, and an increase in the aging process. In a new study, mice engineered to age quickly were tested to see which compounds were best at promoting DNA repair.
Nicotinamide Riboside (NR) shown to increase lifespan of mice by 25%
Only two compounds in this study were shown to have an effect on lifespan in mice engineered to age quickly. Both are considered NAD+ precursors. Nicotinamide Riboside (NR) and Nicotinic Acid (NA).
Nicotinamide Riboside showed the most significant effect, extending lifespan by 25 percent. Nicotinic Acid also had an effect, but only slightly.
Although both have been shown to elevate NAD+ by a similar amount in the body, these two compounds follow different pathways in synthesizing into NAD+ and clearly differ in their effectiveness as shown here.
“NA and NR follow different pathways of being synthesized into NAD, and their oral bioavailability is likely to differ” (1)
Other popular anti-aging compounds were not effective
The following compounds were tested and NONE were shown to significantly alter lifespan or features of neurodegeneration in the mice tested. These compounds were tested for:
Nutrient sensing, reduction in inflammation, enhancement of mitochondrial processes, influence on glucose homeostasis, and nicotinamide adenine dinucleotide (NAD+) metabolism. Compounds tested:
- Metformin
- Acarbose
- Resveratrol
- Aspirin
- Ibuprofen
- Idebenone
- Sodium nitrate
- Dichloroacetate
- Trehalose
- GlcNAc
Difficulty in evaluating interventions that extend health and lifespan
The ability to properly evaluate interventions that can extend health and lifespan have been hampered in the past due to the large number of animals involved, expense, and labor-intensive, lengthy experiments. There has also been difficulty in connecting compounds used in experiments with those that have a beneficial, anti-aging effect.
Few interventions delay or reduce DNA damage
There have been few interventions proven to delay or reduce DNA damage accumulation, which is known to be a major driver of aging. Using mice engineered to age quickly as a screening tool for potential anti-aging compounds was shown to be a good way to show the effectiveness of various compounds to extend lifespan in mice.
More study needed to conclude drug effectiveness
The study also concluded that:
“further studies of promising compounds with different dosages and increased numbers of animals are required to conclude drug effectiveness with more confidence” (1)
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