If you like to geek out on the science of longevity, then today’s video is going to be right up your alley.
We’re going to be taking a deep dive into the number 1 concept that you need to comprehend
in order to understand how the science of longevity works.
If you want to slow or even reverse the aging process, if you want to turn back the clock on aging…
then hit that subscribe button below and subscribe to this channel.
Leave a comment and let me know what you think of this channel
or suggest topics you’d like me to do a video on.
Hit the “Like” button, and hit the “Bell” to be notified when I post a new video.
And watch to the end of this video to find out how you can download this infographic
that summarizes everything we’re going to cover in this discussion about the mitochondria.
In 2013 a groundbreaking paper was published on “The Hallmarks of Aging.”
Of the nine causes of aging identified in this paper, six of them have one thing in common.
The dysfunction of the mitochondria.
The impact that the health of the mitochondria have on aging cannot be overstated.
Malfunctioning mitochondria are not only connected to 2/3 of the causes of aging,
they’re also implicated in most age-related chronic diseases.
So…this is the first in a series of videos that I’m going to be doing about the mitochondria.
We’ll start out by taking a look at what the mitochondria are,
we’ll take a look at their anatomy and we’ll discuss the functions of the mitochondria…what they actually do.
In the follow on videos, we’ll be covering mitochondrial health
and the impact that mitochondrial dysfunction has on aging.
And then we’ll talk about strategies that you can implement today,
to improve the health of your mitochondria.
And for you serious science geeks, I’ll be doing a video on cellular respiration.
OK, so…why this video? Why am I doing a video, in fact, a whole series of videos, on the mitochondria?
Because understanding how many of the strategies work to slow the aging process
takes a basic knowledge of how the mitochondria function,
and the impact that it has on aging when they malfunction.
The mitochondria produce almost all of the energy that your body uses,
and it does this by cranking out ATP…a form of stored chemical energy.
When you work out, or do anything strenuous,
the mitochondria respond by kicking the production of ATP into high gear.
But ATP is also required for every process that goes on in your body.
When ATP production drops, due to mitochondrial dysfunction, you have less energy,
your bodily functions slow down, or worse…they start to function improperly.
This causes cellular damage and this damage accumulates over time.
And this accumulated damage is the very definition of aging.
It’s also an underlying cause in most, if not all, age-related chronic diseases.
But there’s a second reason why I’m doing this series of videos.
In many of the videos that I do in the future,
I’ll be making the assumption that people have a pretty good understanding of the mitochondria,
and if they don’t…this is the series of videos that I’ll be referring them back to.
A good grasp of the mitochondria will be needed to fully comprehend many future videos.
So let’s start out at the 60,000 foot level.
The term “mitochondria” is the plural form of the singular “mitochondrion."
Most scientists believe that the mitochondria were once free-living bacteria
that could perform what we now call cellular respiration.
These bacteria became engulfed by other single-celled organisms
and formed a symbiotic relationship with them over a billion years ago.
Before that, cells weren’t very good at producing ATP,
so they had to absorb ATP that was created by other organisms in their environment.
But as these ATP-producing bacteria were incorporated, they gave their hosts a distinct advantage,
allowing them to survive in more environments
and making multi-celled organisms, including humans, possible.
The mitochondria make up 10% of our body’s mass, and half of our dry-body weight.
They’re usually described as being “bean-like”, but in fact they form a network throughout the cell.
Cells that have the most mitochondria are cells that have the highest energy demands.
So it should come as no surprise that cells of the muscle, the brain, the heart,
the liver and kidneys have the most mitochondria.
Although this number can be anywhere between 1 and 10,000, most cells have several hundred.
Unlike other organisms, mitochondria only appear to originate from other mitochondria.
They have their own DNA and their own transcriptional and translational machinery.
Mitochondrial DNA are found in small, circular chromosomes,
and in contrast to nuclear DNA which has 20,000 genes, mitochondrial DNA only encodes for 13 genes.
Mitochondrial DNA only comes from the mother,
as the mitochondria in the sperm are weeded out in the fertilization process.
Mitochondria are constantly undergoing fission and fusion.
As I mentioned earlier, the mitochondria form a network throughout the cell.
Fusion, where multiple mitochondria fuse into a single structure, leads to mitochondrial elongation.
This allows slightly damaged mitochondria to integrate their contents as a form of genetic complementation,
which in turn enables two mitochondrial genomes with different defects
to individually encode for what the other lacks.
Fusion is considered to be a “youthful” state.
On the other hand, fission leads to mitochondrial fragmentation.
However, fission is also how mitochondria replicate themselves.
Mitochondrial fragmentation plays a role in the degradation of malfunctioning mitochondria
and is considered to be a “dysfunctional” state.
And mitochondrial DNA mutates much faster than nuclear DNA, up to 10 times faster.
This is due to 2 things. First, the mitochondrial DNA is very close to where the production of ATP is happening.
This is along with it’s DNA-damaging by-product of free radicals.
Second, mitochondrial biogenesis, the creation of new mitochondria through fission,
happens much more often than mitosis…which is the division of cells into daughter cells.
And this mutation of mitochondrial DNA plays a huge role in mitochondrial dysfunction.
The mitochondria are organelles that are present in almost all cells.
They’re there in single-celled organisms, in plant cells and in animal cells.
They’re called an organelle because they perform many organ-like functions within the cell.
Let’s take a look at the anatomy of a mitochondria.
OK, so, a mitochondrion is an organelle that is located in most cells…
I think red blood cells are the only cell without any mitochondria.
Other organelles in the cell include the nucleus and the endoplasmic reticulum.
Zooming into the mitochondria, it’s got 2 membranes…the outer membrane and the inner membrane.
These membranes are separated by a fluid filled space called the inter membrane space.
Everything contained within the inner membrane is called the matrix.
This includes enzymes, special mitochondrial ribosomes, granules of ions,
tRNA (or translational ribonucleic acid), and mitochondrial DNA.
There are infoldings in the inner membrane and these are called cristae.
The infolding increases the surface area of the inner membrane
to about 5 times the surface area of the outer membrane.
Since much of cellular respiration occurs across the inner membrane,
this added surface area increases the mitochondria’s ability to produce ATP.
OK, that’s great! But what does the mitochondria actually do? Well, it does several things.
They play a vital role in autophagy, the process of cell death.
They’re instrumental in deciding which cells need to be destroyed.
They regulate cellular metabolism.
They can produce heat when you’re cold, through a process called non-shivering thermogenesis.
And they can store calcium. The body needs a lot of calcium for processes other than bone remodeling.
Calcium is necessary for the release of neurotransmitters from nerve cells
or hormones from endocrine cells.
It’s also necessary for muscle function, fertilization and blood clotting.
Since calcium is so critical to so many processes, the cells regulate it tightly.
So, the mitochondria play a part in this by quickly absorbing calcium ions and holding them until needed.
But the primary function of the mitochondria is to produce ATP.
ATP stands for adenosine triphosphate and it’s a molecule that stores chemical energy.
This chemical energy, and the ATP that stores it,
is the only source of energy that drives 90% of the processes in the human body.
When your brain thinks, when your heart beats, when you work out…
it’s the energy stored in ATP that drives all of this.
And all ATP is produced or recycled in the mitochondria through a process called cellular respiration.
Now, the topic of cellular respiration is so complicated that I decided to give it a video of it’s own.
There’s a link to that video in the description,
or you can click on this card up in the upper right corner of the video.
Cellular respiration takes all the food that we eat and combines it with all the oxygen that we breathe,
and converts them into carbon dioxide and water, creating ATP in the process.
A single sugar molecule gets combined with 6 molecules of oxygen,
and they’re converted into 6 molecules each of CO2 and H2O.
And 32-38 molecules of ATP gets produced or recycled in the process.
Go check out the video if you want to really geek out on how all of this happens.
So, this wraps up this video on the mitochondria.
Besides the video on cellular respiration, there are going to be 2 more videos about the mitochondria.
One on things that effectthe health of the mitochondria
and the impact that poor mitochondrial health has on aging,
and the other on strategies for improving mitochondrial health.
If they’ve been published when you see this video, they’re will be links to them in the description.
If you’d like to download this infographic that outlines everything that we just talked about,
click on the card in the upper right corner of this video, or look for the link in the description.
And if you enjoyed this video and would like more, then seriously,
think about hitting that subscribe button and subscribing to this channel. Hit the like button.
Thanks for watching, and I’ll see you next time.