Study: NMN’s Role in Restoring Liver Health in Aging

Understanding NMN’s Role in Liver Health During Aging

Aging, a universal biological process, brings numerous challenges to our bodies, including the liver, a vital organ. Among various aging theories, the free radical theory. This theory declares that free radicals, which are “unstable” molecules, might be the primary cause behind the deterioration of health as we age. However, not all experts are convinced by this theory.

Think about the concept of adaptive homeostasis. This idea suggests that while young animals have a robust mechanism to defend themselves against various stresses, this defense capability decreases as they age. A protein named Nrf2 is central to this defense mechanism. In this blog, we’ll explore the role of Nrf2 in the aging process of mouse livers and investigate whether NMN (Nicotinamide Mononucleotide) holds the potential to rejuvenate these aging livers.

Key Study Highlights

• Reduction in Oxidative Stress: The study found that NMN treatment reduced signs of oxidative stress in aged mouse livers, suggesting its potential in protecting against age-related liver damage.
• Enhanced Liver Injury Resistance: Mice treated with NMN showed improved resistance to acetaminophen-induced liver injury, highlighting NMN’s protective role against common liver stressors in the elderly.
• NMN’s Mode of Action: The research revealed that NMN works through enhancing the activities of Sirt3 and influencing Nrf2, key players in the body’s defense against oxidative stress. This dual mechanism is crucial for NMN’s protective effects on the liver.

Purpose of the Study

The study starts by highlighting a critical aspect of aging – the disruption of redox homeostasis. This balance, crucial for overall health and longevity, is often compromised as we age. The liver, being a vital organ, is particularly susceptible to these changes. The research explores how NMN, a precursor of NAD+ (Nicotinamide adenine dinucleotide), impacts the aging process, specifically examining its potential to restore redox homeostasis in aged mouse liver.

The Study

Researchers started this study with two types of mice: the regular C57BL/6 wild-type and another group that was deficient in a protein called Sirt3. Sirt3 is not just any protein, it’s known to play a fundamental  role in regulating cellular energy and stress responses.

To understand the effects of aging on the liver, the researchers administered either NMN or a control solution (PBS) to both young and aged mice. The main objective was to observe any differences in the liver proteins between these two groups. To accomplish this, the researchers used a sophisticated technique known as quantitative proteomic analysis. This method allowed them to find differences in protein amounts between the livers of young and old mice.

But the study didn’t end there. The researchers wanted a detailed understanding of the liver’s condition. To do so, they used numerous methods, including immunohistochemical staining, western blotting, and a unique technique known as oil red O staining. Each of these methods offered insights on different aspects of liver health and protein expression.

What they discovered

The results from the experiment were intriguing. As mice age, their liver proteins go through significant changes. The proteins that were most activated were those involved in the oxidation−reduction process. In simpler terms, these proteins were working overtime to protect the liver from potential damage.

Furthermore, the study revealed that NMN had a rejuvenating effect on the livers of aged mice. It effectively reduced oxidative stress and decreased the levels of nuclear Nrf2, a protein that helps protect the body from damage.

But the revelations didn’t stop there. When the mice were given an overdose of Acetaminophen (APAP), a common painkiller that can damage the liver in excessive amounts, the mice that had been treated with NMN showed significant resistance against liver damage. This finding suggests NMN might help bring back the liver’s natural defenses that weaken as we get older.

The Crucial Sirt3 Connection

The story became even more interesting when the researchers turned their attention to mice with Sirt3 deficiency. They discovered that the protective effects of NMN on the liver depended on the presence of Sirt3. This discovery highlighted how crucial Sirt3 is in the way NMN helps revitalize the liver.

Read another promising study on NMN and Liver Health here.

Conclusion

Aging is an inevitable journey, but studies like this offer hope. The research shows the potential of NMN supplementation in protecting the liver from damage caused by aging. It works by teaming up with the body’s natural protective proteins, especially Nrf2 and Sirt3. While more studies are needed, these results are a promising step towards finding strategies to combat age-related liver problems.

Learn more about Sirtuins here.

References

https://pubs.acs.org/doi/abs/10.1021/acs.jproteome.2c00167