Mitochondria: The Key Component in Aging

Are you finding that as you get older you aren’t feeling as energetic as you once did? Tasks that were normally a breeze are now requiring more effort and you are reaching for more caffeine to get through the day?

Well, you are not alone.

The solution to this problem lies within the mitochondria in your cells. These energy factories are responsible for making all the energy your body needs but over time they become damaged and don’t function as well. Therefore, understanding how your mitochondria work and ensuring they are healthy is vital to feeling like your best self.

Mitochondria are Highly Dynamic Energy Factories

Mitochondria are often depicted as singular entities sat alone within the cell. This could not be further from the truth. It is now understood that mitochondria are highly dynamic organelles that form networks which can change size, shape, and mass. Each cell can contain hundreds and thousands of mitochondria. If the cell is very active such as the brain, heart, liver and muscle cells then the number of mitochondria is generally higher. Furthermore, they are highly sensitive to environmental stress such as exercise, calorie restriction, and oxidative stress (the creation of damaging products within the cell). As the energy factories of our cells they are vitally important.

Mitochondria contain their own DNA (often called mtDNA). This is because mitochondria are evolved from bacteria. As a result, their DNA is circular compared to the chromosome (linear) structure of human DNA. This is important as it means new mitochondria cannot be made from scratch within the body (de novo) but instead must be made from existing mitochondria.

Mitochondria are Damaged by Free Radicals

The mitochondria are essential for many functions in the cell and are at the heart of age-related dysfunction. The progressive dysfunction of the mitochondria leads to decreased ATP production, causing the lethargy associated with aging. Mitochondrial damage occurs as, during normal metabolism, the mitochondria produce damaging substances called free radicals. Consequently, the cell has developed protective mechanisms to mop up these free radicals. SIRT3 regulates one of these mechanisms. SIRT3 stimulates antioxidant pathways and stress response pathways to repair any damage and protect the cell.

The issue is that levels of sirtuins and NAD+ decline as we age. This impairs the repair and protect pathways from functioning. Ultimately, resulting in the build-up of these free radicals. Which contributes to the deterioration of the mitochondria, the lack of energy production and enhances aging.

Sirtuins Link the Mitochondria to the Nucleus

Another key aspect is the communication between the mitochondria and the nucleus. We know that the cell is constantly monitoring its environment including nutrient availability, free radicals, and energy levels. In this context the mitochondria and the nucleus are like a perfect partnership. They communicate with each other very well and respond to what the other needs. As we age this communication breaks down, further contributing to the decreased energy production and damage.

So, you may be wondering how SIRT3 fits into this relationship? Well sirtuins are the messengers between the nucleus and the mitochondria. As mentioned previously there are sirtuins located in various places within the cell; some in the nucleus, some in the mitochondria and some in the cytoplasm (the fluid within the cell) to enable this communication. The breakdown in communication is partly due to the lack of NAD+ in the cell. NAD levels decline and because they are needed for sirtuins to function they cannot perform these essential tasks.

So, what can you do to slow this process? Well, one way is to restore your NAD+ levels as you age. Boosting the cell’s ability to manufacture and recycle NAD+ increases the activation of your sirtuins. This ensures your cells are working optimally. The mitochondria are protected from damage and the communication between the mitochondria and the nucleus is intact. Supporting your cells to function like they are young and make all the energy you need.

Find out more about sirtuins and how they are activated.

Find out more about what happens to NAD as you age.