Mitochondria: More than Just Powerhouses

Healthy Aging

A Thousand Tiny Batteries Per Cell

The ability to reverse aging is no longer science fiction. Sounds too good to be true? In this series, we are talking about the latest peer-reviewed science on how slowing, and even reversing aging is becoming a reality.

This week, let’s talk about another hot age-reversing target: mitochondrial dysfunction.

Great! Wait – what is mitochondrial dysfunction?

Mitochondrial dysfunction is when the powerhouses of our cells stop working properly. As we get older, more and more of our mitochondria peter out, resulting in less cellular energy, more cellular stress, and advanced aging-related breakdown.

Aside from being powerhouses of our cells, what else do mitochondria do?

While popular drawings of cells typically include one giant, kidney-shaped mitochondrion, in reality, each of our cells contain thousands of mitochondria. Yes – thousands. These microbatteries have many important functions, including:

• Maintaining intracellular homeostasis. Mitochondria are constantly reading the “cellular room” to turn energy up and down as needed, helping to keep our cells healthy and balanced. When our mitochondrial sensors go awry, our cells become unbalanced – along with our whole body health.
• Metabolizing nutrients. Mitochondria turn nutrients into energy, especially dietary fatty acids. When the function of our mitochondria are compromised, these nutrients start backing up in our cells.
• Communicating with the nucleus. The nucleus and mitochondria have direct lines to each other, in which mitochondria ask the nucleus, “Are we okay?” And the nucleus responds, “We are okay.” Until our cells are not okay.

Mitochondria have a kill switch.

When our mitochondria are happy, our cells are happy. When our mitochondria go awry, however, they stop making energy and start making reactive oxygen species (aka ROS), which damages our cells.

As we age, this mitochondrial kill switch is increasingly triggered, contributing to our age-related breakdown. As described by Haas in a Special Issue on Mitochondrial Dysfunction in Aging and Diseases of Aging, dysfunctional mitochondria can contribute to the development and worsening of:

• Immune malfunction
• Poor wound healing
• Poor retinal health
• Diabetes
• Cancer
• Cardiovascular disease
• Neurodegenerative disorders

Taming misbehaving mitochondria.

Mitochondrial-targeted antioxidants are popular supplements that attempt to mitigate the negative effects of dysfunctional mitochondria by decreasing ROS damage. In a recent publication, Mason et al. reviewed 19 clinical trials and concluded that mitochondrial-targeted antioxidants had limited evidence in supporting clinically relevant health indices. As such, while the intent of these interventions are good, mitochondrial-targeted antioxidants may not be the ultimate healthy aging fix.