Break it down to build it up ... The key to proper skin barrier function.
When it comes to skin, breaking it down to build it up might seem counterintuitive at first. But think about it - keeping in mind the skin is an organ and the largest one we have …
Muscles for example. If you want to have defined muscles, what do you do? You break it down into small sections and choose targeted exercises.
Plants for example. If you want bushy leaves, what do you do? Trim them back, right?!
Rooftops for example. If the shingles on a roof aren’t laid in an organized fashion or are clogged with debris from nature, it will cause issues, right?!
It is similar to skin ….
The stratum corneum is the outermost layer of the epidermis and marks the final stage of keratinocyte maturation and development. Keratinocytes at the basal layer of the epidermis are proliferative, and as the cells mature up the epidermis, they slowly lose proliferative potential and undergo programmed destruction.
It is an amazing organ, view it as your body suit. This is a fascinating tissue in all of biology.
What is the distinguishing feature of the stratum corneum? Simply said it’s dead!
Even though we have this dead tissue on the surface of the skin, that dead tissue is incredibly important. Even though it is overall dead, there is biochemistry occurring in the stratum corneum.
The skin itself is about as thin as 11 sheets of paper. 10 of those pieces of paper are in the deeper level, called the dermis. Above that is the epidermis, which might be as thin as 1 piece of paper and then the stratum corneum - the barrier - is as thin as 1/10th piece of paper. Thats pretty thin.
That stratum corneum layer, as thin as it is and as dead as it is, holds everything in place. If we didn’t have a stratum corneum barrier, we would just be scattered all over the place. Therefore it is incredibly important. Not only does it act as a barrier, it also protects the tissue underneath.
Keeping the stratum corneum healthy is the key to keeping your skin healthy. When the stratum corneum barrier is not as healthy as should be we get sensitive skin, we get dry skin, we can get hyperpigmentation, we can have bacteria assault issues, we can have all kinds of health issues just by not having a healthy strong stratum corneum.
Did I paint the picture?
Understanding how to build a strong healthy barrier stratum corneum is the very essence of good skin care. There are various ways in how to go about it.
First, lets talk about how the stratum corneum is built.
We have these layers starting at the bottom with the dermis. The dermis is made up of stem cells, then those stem cells give birth to skin cells. The technical term for skin cells is keratinocyte. Keratinocyte (keratin) is a hard protein that these cells manufacture. So Keratinocytes are born at the basal layer (the basal layer is the innermost layer of the epidermis), round, plump, and juicy. And one of the coolest processes is that this keratinocyte rises up to the top. And as it rises up from the basal layer to the stratum corneum it becomes shape-shifting. It is changing shape from round and plump and juicy to flatten and dead at the end. As it rises from bottom to top, it loses its contents and biochemical changes are occurring inside that keratinocyte.
It is so amazing how this is happening. There is a lot of chemistry that has to go right for this to occur.
Almost all skin diseases (psoriasis, acne, eczema, dry skin, hyperpigmentation) can be resolved by defects in the movement of cells as they are rising from the bottom to the top.
Because they are taking on a different shape as they are rising from the bottom to the top, we call this process differentiation. The differentiation process is the key to healthy beautiful skin because as the shape-shifting is occurring, as the cell is differentiating and dumping its content overboard and its changing chemistry inside the cell, it's making a perfect stratum corneum cell, which is called the corneocyte.
The content that is thrown overboard will go on to form fats that coat the surface of the skin (we often refer to it as oil). Inside the keratinocyte, as it's rising from the bottom to the top biochemical changes are occurring that are going to produce natural moisturizing factor molecules in the corneocyte to trap water. And then the shape-shifting itself is creating a flat dead cell that is perfect for functioning as a barrier. All the stratum corneum barrier elements are produced as the cell rises from the bottom to the top. Which makes this differentiation process key.
As we get older, we don’t differentiate as quickly. Our cells don’t rise from the bottom to the top as quickly and this accounts for stratum corneum defects. Today, the stratum corneum barrier defects are epidemic.
Almost anyone not taking care of their skin will have some degree of stratum corneum defect. This is where excema shows up, psoriasis, acne, dry skin, hyperpigmentation, and sensitive skin.
Hence, building the stratum corneum barrier is the very essence of anti-aging skincare.
How do we do that?
As you now know, speeding up or stimulating the movement of the cells from the bottom to the top is very important. That is helping the cells to go from the stem cell level to the keratinocyte level and rise up to the stratum corneum. That is where exfoliation comes in. Exfoliation is like exercise. This is going to be your main weapon to turn on the growth of your cells from the bottom to the top. Exfoliation has stimulating effects on the dermis and fibroblasts and collagen and elastin and hyaluronic acid and such. If you will, it keeps your muscle building, your plants nice and bushy and your rooftop intact.
If you have a defective stratum corneum you have to be careful. You want to stimulate, but if you have a defective stratum corneum, you don’t want to overstimulate. It's an art form and you want to do it just right. You don’t want to overstimulate, but you want to stimulate somewhat. Start off slowly, take days off, kind of like an exercise program. If you just got out of the hospital you are not going to start benching 25 lbs, but that doesn’t mean you don’t want to start somewhere. Same with an exfoliation program.
Again, did I paint the picture?
One of the very effective options is alpha hydroxy acid. Not only do they turn on the growth of cells by virtue of their ability to disrupt the stratum corneum, but they also dissolve the glue that holds the corneocytes together. That in turn sends down a signal to the bottom to get some more cells going, and alpha hydroxy acids do a couple of other very interesting functions.
Number one, they deliver acids in a form of protons to the cells underneath. That has an extra stimulating effect at the level of the keratinocyte. This means you get a stimulating effect by virtue of the dissolution or disturbance of the corneocyte, but then get an extra benefit by protons and by acids, which further stimulate the keratinocyte.
Also, the skin is acidic. That is the nature of the stratum corneum. Until we age or our skin is unhealthy the skin pH becomes alkaline. Alkalinity creates an unhealthy environment for the skin microbiome, it creates an unhealthy environment for the skin cells, it creates overall disturbances in skin health.
Alpha hydroxy acids have an acidifying effect. In fact, AHA’s are actually in the stratum corneum anyway. That’s why we refer to the acidic skin with its AHA content as the acid mantle. The acid mantle is made up of AHA’s, lactic acid, amino acids, and fatty acids. AHA’s restore the acidity of the skin surface, stimulate the keratinocyte by delivering protons or pieces of acids and they have an exfoliating effect on the corneocytes, which also triggers the growth of cells.
There are also other ingredients that turn on the growth of cells, but for now, we’ll leave it at that.
Put intention into your skincare routine. Maintaining your skin is a lifelong commitment. Taking care of your skin is just like taking care of your body–it is part of a lifestyle.
Skin Fit Rox was founded to provide a European standard of full-spectrum skincare using home care coupled with skincare services with an emphasis on client safety - delivering superior client results in an inviting, contemporary environment.
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