Does mitochondria hold the secret to youthful looking skin?
We all want to have healthier, younger-looking skin. But with so many products offering miracle treatments to improve our skin, how can we know what really works, and what is just good ad copy? Understanding the science behind how our skin ages is the first step to learning what keeps skin looking young and healthy for longer.
The powerhouse of the cell
You probably remember from school that mitochondria is the powerhouse of the cell, but do you remember what that really means? What is mitochondria, and what does it do? More importantly, what the heck has it got to do with the signs of aging?!
Mitochondria are tiny organelles found inside the cells of almost all living things. Their primary function is to produce adenosine triphosphate (ATP), an organic compound that cells use as fuel. This is called “cellular respiration.” Without ATP, your cells will die, and that makes mitochondria important to your overall health, not just your cells.
Each mitochondria has two membranes. The outer membrane is smooth, and gives the mitochondria its rounded or oval shape. Inside is a second membrane that is folded, rather like an intestine. This increases the surface area of the membrane, and makes the mitochondria more efficient at creating ATP.
Between the membranes is a gel-like substance that holds mitochondrial DNA (mtDNA), RNA, and ribosomes. The mtDNA contains all the genetic information the mitochondria needs to function and replicate. The RNA and ribosomes convert that information into actions, a bit like a computer reading data to run a program.
That means mitochondria is super important to cellular function, and mtDNA is the blueprint that makes it all work.
When mitochondria go wrong
Turning food into ATP is a complex chemical reaction, and it often goes wrong. When that happens, it leads to the production of Reactive Oxygen Species (ROS), a variety of free radical molecules.
Free radicals are chemical compounds that contain a single electron. Because electrons always want to be in pairs, the molecule will “steal” an electron from other compounds to solve the imbalance. That destabilizes the other compounds, and can lead to damage and mutations.
Think of free radicals like car pollution. Newer cars produce less pollution, just as younger cells contain less free radicals. But as our cells age, that damage can build up and become problematic. If free radicals get out of control, they can even cause cells to die. This is known as oxidative stress.
Oxidative stress is a big problem for mitochondria because they create free radicals as a byproduct of their normal function. The highest number of Reactive Oxygen Species in cells are found in the mitochondria, making them more prone to mutations. In fact, mtDNA mutates at a rate 10 times higher than that of nuclear DNA, mostly because of its increased exposure to ROS.
While some mutations are good — that’s how evolution works — within mitochondria, they’re bad. As mtDNA undergoes more and more mutations, it begins to break down, making the mitochondria less effective at producing the ATP that powers the cell. It can even stop production completely. When this happens, the cell dies.
What happens to our skin when cells die?
Cell death (“apoptosis”) is a normal part of the function of our bodies. Adult humans lose more than 50 billion cells each day, which are replaced by new cells that continue to maintain our bodies and keep us healthy. However oxidative stress causes cells to die prematurely, leading to organ malfunctions, cancer, and degenerative diseases.
While all that sounds scary — and it is! — a good place to look for signs of mitochondrial health (or degeneration) is your skin. Your skin is your largest organ, and is exposed to the harshest conditions of any in your body. Its function is to protect all your internal organs from temperature extremes, UV damage, pollutants, and bacteria and viruses. Skin is tough, and it goes through a lot every day, and that means it is constantly renewing.
However all that renewal can be a problem. High levels of growth mean there are more chances of mutations, both through oxidative stress and the replication process. When 50 billion cells are being replaced each day, that's a lot of opportunities for error! And because skin is thin and very visible, it's easy to see the changes caused by mutations. If oxidative stress causes mitochondria functions to slow or stop, it shows up in the signs of aging like lines, wrinkles, and age spots.
UV damage and its effect on mitochondria and skin health
As well as oxidative stress, skin cells come under another type of damage that mutates mtDNA — sunlight. The mitochondria in cells that produce keratin are particularly sensitive to ultraviolet radiation. MtDNA mutates at a rate 10 times that of nuclear DNA, but when exposed to sunlight, that rate increases astronomically, up to 10-fold again on top. That means the mtDNA in sun-exposed skin cells can mutate 100 times more than regular DNA.
This is bad news for our skin, because UV sunlight is everywhere, and it doesn’t take much to damage mtDNA. Just two weeks of sun exposure can increase mtDNA mutations by as much as 40 percent. And that damage doesn’t go away once those cells have regenerated: the same study revealed that it took the mitochondrial DNA 16 months to heal.
How to keep mitochondria healthy and reduce the effects of premature aging
The secret to healthy, youthful-looking skin lies at the smallest cellular level, with mitochondria. The more we can protect mtDNA from damage caused by UV light and oxidative stress, the better our cells function. One of the most important steps to protecting our skin is to use UVA/UVB sunscreen on a daily basis. This is effective at preventing signs of premature aging, burns, and even cancer.
Most of us remember to pack on the SPF when we’re at the beach, but it's important to use sunscreen all the time. Even on cloudy or cold days, UV light still reaches us. Many moisturizers and foundations now include SPF, so it’s easy to incorporate sunscreen into your daily skincare routine.
Another way to protect your mitochondria is to combat oxidative stress with antioxidants. These are molecules that seek out free radicals and neutralize them, preventing them from destabilizing surrounding molecules such as mtDNA. You can get antioxidants through your diet, from foods like fruit and vegetables. Some skincare products also contain antioxidants. Studies have shown that applying these products can reduce Reactive Oxygen Species and protect mitochondria from mutations.
In conclusion…
Maintaining youthful, healthy-looking skin is a balancing act of diet, environment, and good skincare habits. We can help ourselves by eating antioxidant rich foods, and using skincare products with antioxidants and SPF. Supporting our mitochondria shows in healthier, clearer skin.
Understanding and nourishing your skin at the cellular level is what Qyral does best.
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Sources:
- “Mitochondrial Dysfunction in Aging and Diseases of Aging,” by Richard H. Haas, Biology (Basel). 2019 Jun; 8(2): 48.
- “Programmed Cell Death and Inflammation: Winter Is Coming,” by Joseph P. Kolb et. al., Trends Immunol. 2017 Oct;38(10):705-718.
- “In human keratinocytes the Common Deletion reflects donor variabilities rather than chronologic aging and can be induced by ultraviolet A irradiation,” by H. Koch et. al., J Invest Dermatol. 2001 Oct;117(4):892-7.
- “Induction of the photoaging-associated mitochondrial common deletion in vivo in normal human skin,” by Mark Berneburg et. al., J Invest Dermatol. 2004 May;122(5):1277-83.