- Hi Bernie.
I hope you're well during these crazy times. I was trying to post on the forum but couldn't find how to do it, I apologize if this has come through to the wrong place! I did your training a few years back. I have a question that was asked to me by a student and I'm having difficulty finding a clear answer, I'm wondering if the science has changed?
In the manual from your course (I think I trained in 2016) and in the old version of your book "the complete guide to Yin yoga", it states that HA is manufactured /secreted by fibroblasts (and that collagen is also secreted by fibroblasts). However in your new book version, it talks about fasciacytes producing water hugging molecules, and wikepedia also talks about fasciacytes and HA too.
So my question is: Which cells create/secrete/produce HA? Do fibroblasts produce collagen/elastin, and fasciacytes produce HA? Or perhaps both fibroblasts and fasciacytes produce HA? Does the HA move around the collagen in the extra cellular matrix, or does it move within collagen fibres? Does the production of more collagen stimulate the production of HA, how can I understand their influence on one another? The more I research the more I'm getting confused! I also had a look on the forum and found articles on HA but as they were dated from 2017 I was hoping to get a more recent answer to be sure I'm up to date with the latest science.
Many thanks for all that you do, you are an inspiration. Gemma
It is nice to hear from you. Yes, science ever marches on. Researchers are continually refining what we know. I believe it was Carla Stecco who “discovered” fasciacytes. (See Hyaluronan within fascia in the etiology of myofascial pain.) They live in the epimysium, which is the layer of fascia surrounding the whole muscle bundles, which is where the most lubrication is needed. (You can check out her research paper The fasciacytes: A new cell devoted to fascial gliding regulation .) But, just because fasciacytes produce hyaluronic acid (HA), doesn’t mean other cells don’t produce it. It is just that fasciacytes seem particularly adept at it. Another study Quantification of hyaluronan in human fasciae: variations with function and anatomical site, by Catarina Fede, who is a coworker of Carla Stecco, talks about how the amounts of HA varies from place to place within the body.
While it only adds up to about 15 grams of an average person’s body mass of 70 Kilograms, it is everywhere! It is in the vitreous fluid of your eyes, in your blood serum, skin, joints and of course, in our fascia and muscles. So, just because fasciacytes in our fascia produce HA, don’t think that other cells don’t produce it. They can and do. Indeed, 50% is in the skin and 25% in the bones and joints. (See Biology of hyaluronan: Insights from genetic disorders of hyaluronan metabolism.)
Unlike most glycosaminoglycans (water loving molecules like chondroitin sulphate) which are produced in the cell’s golgi apparatus, HA is produced by the cell membranes. All mammalian cells can produce it. (See Genetic basis for hyper production of hyaluronic acid in natural and engineered microorganisms
.) Hopefully, this answers your first questions: all cells can produce HA, but some cells specialize in its production and where it is needed the most, you will find a lot of those cells.
The HA doesn’t go inside collagen: think of it as a lubricating layer between fibers which helps them slide and glide over each other. But, like a lot of things in life, you can have too much of a good thing. Carla’s brother Antonio Stecco (who is also a fascia researcher) reports that too much HA creates an aggregate stickiness that is unhealthy and binds the tissues so they no longer glide. However, if you warm up the tissues to about 40C, it will “melt” a bit and desegregate—which may be why hot yoga works so well to loosen you up. Long held stresses (yin yoga!) may do the same.
I hope this helps