Updated: Jan 4
Today I would like to discuss my thoughts on some very recent research that challenges our understanding of a critical cellular component: the mitochondria. Now, you might have lost some of what you learned in school about mitochondria, so what I want to do today is talk briefly about what they are. Just as a reminder, this won't be so in depth that I bore you to death. Feel free to do your own research on the topic for a more inclusive analysis. I would like to talk to you about the mitochondrion itself, what we know about the role of the mitochondria in laser therapy, and then get into a more recent discovery about mitochondria and how it can affect the way that you're using laser therapy in practice.
The mitochondria is the powerhouse of the cell!
So, first of all, the mitochondria is a specific cellular organelle found in most cells. There are only a few cell types that don't have this but, in most cases, you're going to have between a few to 2000 mitochondria in every cell. The mitochondria’s main task is to generate ATP (Adenosine Triphosphate), which is your main source of fuel in the cell. Without ATP, the cell will die and cannot function. However, with good amounts of ATP production, the cell can replicate, divide, repair, and grow. This is why mitochondria are such a critical component of the cell. It also has important roles in cell signaling, but we'll get to that later on.
Cellular energy production
Let's break down how the mitochondria actually looks and functions.
You have a double membrane structure composed of an outer membrane and an inner membrane. Between the two of them is the intermembrane space that houses the matrix. Now, the outer membrane contains the inner membrane space, obviously, but it also has a lot of transport proteins. Those transport proteins are responsible for maintaining the environment of that intermembrane space because, in that space, there are specialized proteins like cytochrome C. Does that sound familiar?
If these specialized proteins leak out of that intermembrane space into the rest of the cell, then it actually signals cellular death or apoptosis. The environment of that intermembrane space is very important for the function of the inner membrane, the matrix, and the two's relationship because the inner membrane contains the electron transport chain. Additionally, it contains ATP synthase. Further, inside the inner membrane is the matrix which contains the citric acid cycle enzymes. This is how you start to talk about producing a potential within those membrane spaces so that work can be done to accomplish the process of creating ATP. This is done by producing a proton gradient across that membrane and pumping protons into the intermembrane space (which produces this thermodynamic state), that can therefore be utilized to perform oxidative phosphorylation. ADP is then phosphorylated to ATP, produced, and then pumped out into the cell.
This process is termed the Krebs Cycle of Electron Transport. What happens is different complexes pass those electrons along so that they gain more and more potential. The last step is complex IV, which is cytochrome C oxidase. This particular enzyme uses the electrons and hydrogen ions to reduce molecular oxygen to water to fuel this proton pump activity and is what allows us to produce ADP and water combined. Cytochrome C oxidase itself contains copper ions and heme groups which gives it the title cytochrome. The total meaning is that it is a chromophore and responds to light as well. This is an important distinction when we start talking about the ability of laser therapy to have a role in this mitochondrial production of energy.
Laser and mitochondria - in theory
Currently, everything discussed above is pretty well established in scientific knowledge. However, this next piece is fairly theoretical. While we think we know quite a bit, none of it has really been solidified. What we believe we know is that certain colors of light have an effect on cytochrome C oxidase as well as the mitochondrial bound water layers. This is important because if you can improve the efficiency of the cytochrome C oxidase functioning and you can improve transport of mitochondrial-bound water, then you can have more efficient, more effective mitochondrial function. This means more energy production, and more energy production means:
increased cellular vitality
increased cellular ability to repair
increased cellular ability to replicate
increased cellular ability to divide.
We know that certain colors of red and near-infrared light absolutely do speed up the production of ATP. So, if you can get light to these organelles, then you should be able to improve their function, which in turn improves their cellular function and cellular health.
I spy with my little mitochondrion eye...
Now, that brings me to the study that I want to talk to you about today. As you know, everything we do on this podcast is based on scientific studies (excluding the pieces where we talk about clinic development and so forth), and the research study we're talking about today is truly groundbreaking. The aforementioned study was published as of November of 2019 in the journal of The Federation of American Societies for Experimental Biology with the title, "Blood Contains Circulating Cell-Free Respiratory Competent Mitochondria."
Now, let's break that title down for just a minute before we go on here. Blood—just free blood—contains circulating, cell-free, respiratory-competent, functioning mitochondria. They're saying that not only are these important organelles contained within cells, but there are functional mitochondria in the bloodstream freely circulating. This is a lot different than what I was taught in school 10, 15 years ago now. At that time, we thought that, really, these were isolated to the cells, and more recent research has shown that maybe there's some in platelets as well. Yet, this study from 2019 talks about cell-free, functional mitochondria circulating freely in the blood.
A majority of this article talks about their methods of how they found these mitochondria, so I am going to jump into the discussion as I believe we have covered most of the basic sciences and processes above. They go on in the discussion to say that there are structurally intact, cell-free mitochondria in the blood circulation that are respiratory competent. They estimate between 200,000 and 3.7 million cell-free and intact mitochondria per milliliter of plasma. Furthermore, they've seen this in both healthy individuals as well as patients with mitochondrial disease. This is really intriguing because a lot of what we think about as clinicians when we're delivering laser therapy in particular is that we're trying to get light to the cells of the site of damage so that we can help those cells repair, right? That's a big function of what most of us think we are doing when it comes to light and laser therapy—providing light of the right type to those cells to assist the cells in repair by generating better mitochondrial function, better ATP production, and improved cellular signaling (such as the production of increased nitric oxide as well as even improved circulation).
What does this fact mean when it comes to medicine and light therapy in particular? Let me read you a little bit more from the study before I go into how this has to do with what we're doing with laser therapy in particular. The researchers say, "we believe that circulating, cell-free, intact mitochondria have crucial biological and physiological roles because mitochondria are already known as systemic messengers in cell-to-cell communication by transferring hereditary and non-hereditary constituents. Mitochondria were recently discovered to translocate from one cell to another, and it has been demonstrated that these organelles harbor many damaged associated molecular patterns, including DNA, lipids and metabolites, which are capable of activating immune cells and inducing an inflammatory response."
Laser, organelles, and systemic effects
This is fascinating because, not only are we talking about this process happening within a cell and immediately around that cell, but now we're taking this organelle, putting it into the bloodstream and freely circulating it. What could it be doing? What is the purpose of that freely circulating, intact mitochondria? Well, we just don't really know yet. Hopefully in the next year or two, we see some further studies on this because it could be a huge factor in many different disorders and many different therapies. But, let's talk about what it might mean for laser therapy. This is where I'm going to get a little bit speculative with you because we don't know yet. We don't have the research on this. So, let's play the guessing game! We know that laser therapy stimulates improved signaling and improved mitochondrial function. We also know that laser therapy does affect the tissues you are working on directly. Conjointly, it also has some kind of systemic effect in many cases where not only do you see results right where you are shining the light, but also in other locations throughout the system. Further, there have been some studies on blood irradiation by red and near-infrared light and how that might function as well.
Once you take all of these pieces and put them together, we know red and near-infrared light stimulates improved mitochondrial function in cell signaling. When we not only irradiate the target cells, but also the blood supply, we could see benefits and changes in not only the cells we're targeting, but in other areas distant to the site we are actually treating. I think this can explain quite a bit in terms of the general fatigue that we see after many laser treatments and body-wide aching for a short period of time. Those are about the only side effects we ever really see with light and laser therapy. If you're not only irradiating a particular tissue, but also the blood supply through that area, you could be looking at some significant systemic effects that could positively affect a patient's progress. Even in tissues that are difficult to reach: the brain, the organs, even deep muscles like the psoas. We're talking about maybe being able to affect those tissues simply by working on the blood supply. This is fascinating!
We don't know a lot of what could be possible here but, as new pieces get discovered, you can definitely count on LTI to bring you the latest in the research! Not only information on laser therapy, but also related research that can impact your patient's progress.
Clinical application of research with Laser Therapy Institute
I'd encourage you to keep listening to the podcast, visiting this blog, subscribing, and sharing these articles with others you might think would be interested. You probably have classmates that went through medical school or PT school or chiropractic school with you that would be interested. I think it's interesting that effects we've been seeing for years with laser therapy are finding science that actually supports what we've seen on the clinical level.
I appreciate you joining me this week, and I appreciate your reviews and your feedback and your suggestions. I hope you come back and join us again next week. We have a very special end of the year episode planned to talk about how to integrate laser therapy into your practice, some of the things you should be considering, and how to make sure that you're going to be successful for your patient's health.