What Are Sirtuins and How Do They Support Healthy Aging?
For decades, scientists have sought to better understand why we age. Scientists believed that aging was simply a natural part of our human development and that little could be done to stem the tide of physical deterioration. However, in the 1990s, a groundbreaking discovery revealed that a specific family of genes and their resultant proteins regulate aging; further research indicates that modulation of these genes and proteins may improve the way we age. These genes are known as SIRT genes, and the proteins are called sirtuins. Read on to learn about sirtuins, how they support healthy aging, and what you can do to optimize your sirtuin activity.
What Are Sirtuins, and Why Should You Care About Them?
Sirtuins are a family of seven proteins that play regulatory roles in almost all cellular functions. Sirtuins impact the body’s inflammatory balance, cell growth, circadian rhythms, energy metabolism, neuronal function, and stress resistance.[1] At a biochemical level, their primary mechanism of action is removing acetyl groups from an amino acid called lysine found in proteins throughout the body. Removing this acetyl group in a process called “deacetylation” activates the target protein, allowing it to perform its vital functions in the body. Histones, the proteins around which our DNA is wound, are one group of proteins modified by histone deacetylation. Deacetylation of histones regulates gene expression, ensuring that your genes are turned “on” and “off” at the right time in your body.
Nicotinamide adenine dinucleotide (NAD+) is an essential cofactor required for the activation and function of sirtuins.[2] Without sufficient NAD+, sirtuins cannot effectively regulate the body’s inflammatory balance, metabolism, and stress response system, leading to a breakdown of bodily functions.
NAD+ levels naturally decline with age. In fact, age-related NAD+ depletion may play a role in age-related health concerns, such as declines in metabolic health and cognitive acuity.
The Car and the Driver: How Sirtuins Drive Our Body Functions
The concept of sirtuins can feel pretty abstract, even to those of us with years of science education! To better understand how sirtuins impact the body, let’s draw a quick analogy.
If we compare the human body to a car, then sirtuins sit squarely in the driver’s seat, deciding when and where to turn a corner, pump the breaks, or increase speed to squeeze through a yellow traffic light. In your own body, sirtuins similarly “drive” numerous body functions.
Using the same car analogy, we can compare NAD+ to a car’s gasoline. Gas provides fuel for the vehicle, enabling the driver to decide where, when, and how to drive the car. Similarly, NAD+ provides power for sirtuins, allowing them to perform their vital activities.
The car’s driver also makes decisions that impact how well the car ages. He or she determines when it’s time to take the car into the shop for repairs and how often the oil is changed, factors that significantly impact how long a car will last. If the driver doesn’t perform these tasks, the car will age poorly and soon be non-functional. Conversely, a conscientious driver can keep a car in good shape well over the 200,000-mile mark, allowing the car to age with grace. A growing body of research indicates that sirtuins act in the same way, exerting a powerful influence on how our bodies age.
Sirtuins Regulate the Way You Age
The aging process is characterized by declines in numerous body systems and function, including:
- Impaired blood sugar regulation
- Reduced cognitive acuity
- Decreased energy and stamina
- Impaired vision
- Reduced collagen production in the skin, leading to lackluster skin and wrinkles