Growth Factors and Stem Cells: Scientific Innovation or Pure Hype?
Just as our world changes rapidly, so does the beauty realm and the science behind cosmetology and skincare. As the future of beauty is revealed, you may have heard about the idea of using growth factors and stem cells in products to slow the effects of aging, whether natural or environmental aging occurs. There are two types of aging—intrinsic which is the progression of aging through the natural process of time and loss of collagen and elastin and extrinsic, which is the progression of aging due to environmental factors like toxins, pollution and smoking. To battle this aging process, beauty companies promise to infuse the inside and outside of the skin with growth factors and stem cells that slow skin aging by promoting cell turnover, increasing the extracellular matrix protein, enhancing collagen and the production of ECT (a natural preservative).
Wave of the Future
So where did the idea for this technology come from? As space age as it may sound, the process of using growth factors and stem cells to treat damaged tissue isn’t new. In fact, using growth factors and stem cell related factors originated from the treatment of wounds and burns in the medical field. Clinical studies have proven positive effects of growth factors/stem cell therapies in expediting the healing process of wound/burnt victims. These therapies are currently also used in treating patients with neurological disorders and cancer. So, in theory, it sounds like a relatable and good idea to apply to the treatment of aging and skincare, right?
When it comes to skincare, however, it might not be that easy. You see, the skin barrier which usually only allows in minute molecules is impaired in wounded or burned skin. This wounded skin then allows the penetration of large molecules (like growth factors) through the impaired barrier. With daily skincare products, they are applied to the intact skin in most cases and this is where the problem comes in. That’s not it, either. Current research has shown that the dominant factors controlling aging come from the local dermal or systemic environmental causes (extrinsic), rather than natural (intrinsic) stem cell alterations. And to date, the reports on the effectiveness of growth factors/stem cells are scarce (most coming from skin care companies which sell those products). Let’s investigate their use a little further to really decide if their use is valid or just a lot of beauty hype.
Part 1. Growth Factors
When it comes to understanding the new age of skincare, growth factors are a great place to start. A growth factor is a naturally occurring substance, usually a protein or steroid hormone, that encourages cellular growth, proliferation, healing, and cellular differentiation. Growth factors are important for regulating a variety of cellular processes, including division and differentiation. They sound amazing, right? And they are, they’ve been found to help aid in anemia, kidney treatment, cancer, and aids. So why not add them to your skincare regimen? Before you do, let’s uncover a few problems with the growth factors in beauty care debate.
Problem 1: Growth factors are BIG.
And when it comes to molecule size, they’re really big—making them almost impenetrable to the skin barrier. A molecule’s atomic mass unit or its molecular mass is measured in what’s known as Da’s. A growth factor has a molecular size generally greater than 15,000 Da which means they are too large to break through the protective covering of the skin. In fact, molecules larger than 500 Da cannot easily penetrate the skin barrier.
Problem 2: Faulty Storage Abounds
For growth factors to be stored and transported, the proper conditions must exist. Unfortunately, research is showing that the protein degrades at a faster rate than is acceptable for pharmaceutical products. All around, it’s just hard to keep growth factors active in our current skincare manufacturing and storage conditions. What does this mean for your beauty products that boast about including a coveted growth hormone? By the time they reach you, they’ve already lost their effectiveness.
Problem 3: Growth Factors are Socially Awkward
These proteins exert their functions through binding to their corresponding receptors on the cell surface and activating certain signaling pathways within the cell. The signaling pathways regulated by growth factors form a comprehensive network by interacting with each other, so adding or withdrawing one growth factor can trigger many unpredictable changes. Let’s take the well-established growth hormone replacement therapy as an example. Well-controlled studies of the effects of recombinant human growth hormone treatment in endocrinologically normal elderly subjects report small improvements in body composition and a number of undesirable side effects in sharp contrast to major benefits of GH therapy in patients with GH deficiency. What have we learned from these clinical studies? The natural decline of growth hormones in the endocrine system most likely contributes to unwelcome effects of aging on body composition, skin characteristics and functional changes contributing to the general quality of life, but at the same time may offer protection from cancer and other age-related diseases. Thus, growth hormone replacement therapy is almost certain to involve both risks and benefits. Here is another example, one important cytokine that can induce collagen production is TGFβ. However, too much TGFβ will lead to fibrosis, an undesirable medical condition, and we currently do not know what the appropriate dosage of TGFβ is to induce collagen production without causing fibrosis.
With this knowledge, you may start questioning the skincare products infused with so-called growth factors. What growth factors are in there? Do they contain sufficient amount of growth factors to elicit any positive effect? Will there be any side effect?
Part 2: Understanding Stem Cells
You may have heard the buzz about stem cells, whether it be the benefits of banking cord blood or the production of the sheep, Dolly. Stem cells are pluripotent cells that can produce offspring cells and regenerate tissues. Both plants and animals contain stem cells. Research has been taking off in the field of stem cell research and is seeing no possibility of slowing down anytime soon. The possibilities that stem cells open up for treating everything from cancer to AIDS to degenerative disease, is exciting and ongoing. There are different types of stem cells and that’s important for the diseases or problems they seek to treat. When it comes to adding stem cells to your beauty routine to counteract the effects of aging, there’s a lot you need to know.
Our epidermal stem cells reside in the stem cell niche in the basal layer of the epidermis. During the aging process, the number of functions of stem cells remains constant whereas the local dermal and systemic environments have changed. These changes weaken the communication between stem cells and the outside world, leaving them insensitive to messages for help. In adults, stem cells basically function as a repairman of damaged epidermal cells. They get a warning message that says a cell has been damaged and needs repair. Thus, they go to work. Adding stem cells medium or extracts (whether from a plant or animal source) in turn does not activate stem cells because the environment is not permissive, but instead, the cytokines and other components in the medium or extracts may temporarily increase the activity of differentiated cells. This leaves behind the same problems as with the growth factor. They are too big to penetrate the skin barrier of the undamaged skin, they don’t store or transport well and they are complicated to understand and hard to train to do a job other than their own. Research just isn’t caught up with just how to make these stem cells do what they need to do in terms of aging.
Looking Ahead-On the Horizon
So does all of this mean there’s no hope for ever using growth factors and stem cells as a perpetual fountain of youth? Absolutely not. Research in this area is fresh and new, innovative and cutting edge. In fact, researchers have made great attempts at understanding if it may be possible for the larger molecules of the growth factors and stem cells derived factors to make it through the skin barrier after such procedures as laser resurfacing or micro-needling. There’s also research that shows these growth hormones and stem cells can enter through larger hair follicles and the sweat glands. There are also smaller molecules, called matrikines, as well as, matrikine-like peptides that may give the same results promised with the growth factor and with an easier ability to penetrate the skin barrier.
Though the results may not be all they’re cracked up to be, the research in the field of growth factor and stem cells are an exciting and wide-open beauty frontier. As science progresses and we learn more about the interactions of these proteins, we can better understand how to cater them to reduce and heal the signs of aging.