Here at Lux, we believe that consumers should be equipped with all the facts and data behind the products they use. Knowledge is power after all, which is why we want to empower you with the science behind the amazing benefits of red light therapy. But in addition to our values and our belief in informed consumerism, the science is just too cool not to share. So, let’s take a closer look at the cellular mechanisms that give red light its power, specifically a quirky enzyme called Cytochrome C oxidase.
let’s take a closer look at the cellular mechanisms that give red light its power, specifically a quirky enzyme called Cytochrome C oxidase.
Research into the biological effects of red light therapy strongly suggest that the benefits of red light arise from its impact on mitochondria. Mitochondria, as you might already know, are the site of cellular respiration, the process through which food and oxygen is converted into energy. Through its influence on the mitochondria, red light ramps up cellular respiration, which means more energy for the cell and an overall improvement in cell function.
cellular respiration, the process through which food and oxygen is converted into energy. Through its influence on the mitochondria, red light ramps up cellular respiration, which means more energy for the cell and an overall improvement in cell function.
There are several stages to cellular respiration, but we don’t need to get into the details of those now because when it comes to red light, it’s the last stage that matters most. This final stage of cellular respiration, called oxidative phosphorylation, is the process that creates the majority of a cell’s ATP. It’s driven by activity in what is known as the electron transport chain. The electron transport chain is a series of proteins and other organic molecules located in the inner membrane of mitochondria that serve exactly the function you might expect of something with that name- they transport electrons. As electrons are transported along the chain, a buildup of energy is created, almost like the charging of a battery. This energy is then used to fuel the process that creates ATP.
As electrons are transported along the chain, a buildup of energy is created, almost like the charging of a battery. This energy is then used to fuel the process that creates ATP.
The final stop along the electron transport chain is a tangled web of light-sensitive proteins called Cytochrome c oxidase (or CcO for short). CcO is assumed to be the means by which red light has its effects because it’s known to absorb (instead of reflect) red light (Hamblin et al, 2016). The ability for red light to influence CcO has been demonstrated empirically as well. For example, a recent study examined small chunks of tissue collected from human forearms following treatment with red light (don’t worry, the humans were cool with it).
the increase in CcO activity was accompanied by an increase in blood oxygenation
This study showed that CcO activity increased following exposure to red-light (Wang et al, 2016). Importantly, the increase in CcO activity was accompanied by an increase in blood oxygenation, which is what we would expect if CcO activity was truly ramped up. Other studies have shown that exposing CcO to red light enhanced activity in the electron transport chain, which resulted in an increase in ATP production (Farivar, 2014).
Electron Transport Chain
Based on these findings and others like them, the seemingly magical property of red light is thought to stem from its interaction with CcO. That is, when a part of your body is treated with red light, the light waves travel into your tissue, where they are absorbed by CcO. Absorption of red light by CcO enhances its activity, which leads to an increase in cellular respiration and ATP production, providing more energy to those cells.
The fact that mitochondria contain a photosensitive enzyme like CcO is an interesting quirk of evolution. The prevailing theory is that long ago, before the emergence of plants and animals, an ancient precursor to eukaryotic cells (the kind of cells that we’re made of) essentially ate a photosensitive bacterium, which would eventually evolve to be mitochondria as we know them today (Sommer 2020). This bacterium used sunlight to produce energy, much like plants do. The energy this bacterium produced was utilized by its new host cell, which, it turns out, is a sweet enough deal for the relationship between bacterium and host cell to persist for more than a billion years. This mutually beneficial relationship evolved over time and ultimately gave rise to life as we know it!
Thanks to the dining preferences of a prehistoric cell, proteins embedded in the membrane of our mitochondria can react to light, which opens the door for red light therapy.
Thanks to the dining preferences of a prehistoric cell, proteins embedded in the membrane of our mitochondria can react to light, which opens the door for red light therapy. Red light can be absorbed by CcO, which boosts cellular respiration in mitochondria, which leads to enhanced cell function and ultimately a whole plethora of health benefits for us.
Sources:
- Farivar, et al (2014). Biological effects of low level laser therapy. J Lasers Med Sci, 5(2):58-62 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4291815/pdf/jlms-5-58.pdf
- Hambin & Demidova (2006). Mechanisms for low-light therapy. Proc. of SPIE, 6140(1). https://www.litecure.com/wp-content/uploads/2016/09/MRH-2006-LLLT-rev.pdf
- Sommer (2020). Mitochondrial solar sensitivity: evolutionary and biomedical implications. Ann Transl Med, 8(5):161. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7154450/pdf/atm-08-05-161.pdf
- Wang, et al (2016). Interplay between up-regulation of cytochrome-c-oxidase and hemoglobin oxygenation induced by near-infrared laser. Scientific Reports, 6:30540. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4971496/
