The Current Market
The anti-aging market is currently a huge multi-billion dollar industry, with products and services ranging from lotions, creams, laser treatments, facials, medications, etc. Everyone, whether they admit it or not, is interested in discovering a method to reverse aging, and a recent study released by researchers, led by David Sinclair, Ph.D., from Harvard University suggests they might have found an important clue to the answer, nicotinamide adenine dinucleotide, also known as NAD+.
So what is NAD+ and why does it have the potential to actually reverse aging? NAD+ is a coenzyme found in all living cells. It is called a dinucleotide because it is made up of two nucleotides, adenine, and nicotinamide, that are connected through their phosphate groups. So what is its role? It is a vital molecule to life as it plays an important role in cellular respiration, the process by which living organisms, including humans, make energy through breathing. Without it, we would essentially lose our ability to effectively create ATP, our “energy molecule”, in our mitochondria. Obviously, it is an important molecule, but what does it have to do with aging? Well, NAD+ levels naturally decrease as we ago, which limits the ability to producing ATP. This leads to vascular aging of skeletal and cardiac muscle, further compounded by the decrease in physical activity that tends to occur as we age. With all of these important roles, NAD+ is a target molecule in research, with many teams trying to develop drugs to increase NAD+ production to not only prevent and reverse aging but also improve other physiological processes.
Sinclair and his team used mice in their study and found that NAD+, in addition to a protein called sirtuin1, or SIRT1, which has been found to delay aging in mice, reversed aging. A previous study by the same group found that NAD+ has a positive feedback interaction with SIRT1. They demonstrated that SIRT1 played an important role in musculature, exercise performance, and physiological response to exercise.
With these results in mind, the researchers utilized NMN, a NAD+ precursor, giving it to a group of mice over two months. These mice were 20 months old, which is an equivalent to around 70 years old in human years. This treatment improved blood capillary number and density, comparable to that seen in younger mice. It also increased blood flow to the muscles. The most surprising result was the change in the aging mice’s exercise ability. They demonstrated an improvement in exercise capacity 55 to 80 percent greater than the control, untreated mice group. They showed this through the mice’s ability to run; the NMN treated group was able to run an average of 430 meters, around 1,400 feet, compared to an average of 240 meters, 780 feet, in the untreated group.
NMN + SIRT1
The researchers also added a second compound, sodium hydrosulfide (NaHS), to see if these effects could be further improved. NaHS is a precursor to hydrogen sulfide, a molecule which increases the activity of SIRT1. A group of mice, 32-months-old which is comparable to 90 years old in human years, received a combination treatment of NMN and NaHS for four weeks. Miraculously, following the treatment, they were able to run an average twice as long compared to that of untreated mice. The researchers also found that the mice who only received NMN were able to run a distance 1.6 times greater than that of the untreated group. Considering the human equivalent age of these mice, it is truly interesting that the combination treatment was able to double their running capacity. The researchers also found an interesting result that the NMN treatment did not provide an improvement in vascular density or exercise capacity in young sedentary mice. However, it did show improvements for young mice that had been exercising regularly. These results demonstrate that age is a key factor in the effectiveness of this treatment, specifically targeting the loss of NAD+ and SIRT1, to address the problem of decrease in exercise effectiveness and capacity.
These results are promising and have tremendous potential in making great strides in the anti-aging field of medicine and research. The team hopes to replicate these findings in humans with the long-term goal of developing NMN-based drugs. Despite the right intentions, the team does note that it is important to consider the fact that neo-vascularization, the formation of new blood vessels, can also lead to negative health consequences, including the unintended growth of tumors. It may take a while before this research is utilized in a clinical study, but it looks like NAD+ may be an important player in the process of anti-aging.