We have a lot of knowledge to share with you about stem cells and their value in skin care. We thought we would start with a current review of ongoing work in human stem cell science to give you some context. In the next few days we will be getting a lot more specific about wound healing, anti-aging, and related applications.
Human Stem Cells: Introduction
Future advances in many medical fields are thought to be dependent on continued progress in stem cell research. In this section, BTF briefly looks at the future of stem cell based therapies in the treatment of traumatic injury, degenerative diseases, and other ailments, and concludes with a review of current cell based therapies (stem cell and non-stem cell) in the field of skin care.
While the possible indications for stem cell based therapies are numerous, the field of stem cell science is young and years (or decades) may pass before today’s “promising” laboratory results translate into useful clinical treatments. Only time will tell whether successes evolve or remain frustratingly elusive. We do know that success is possible.
The first stem cell therapy was bone marrow transplantation, originally accomplished in the mid 1960’s. Last year, there were more than 50,000 such transplants worldwide. In earlier years, infusion of filtered bone marrow cells was performed with stem cells comprising but a very small part of the volume. Newer techniques have made it possible to separate cellular types to enable use of much higher concentrations of stem cells.
Much progress has been made in characterizing stem cells and understanding how they function. There is much more to the story than differentiation into tissue specific cells. Recent research shows that perhaps even more important is the fact that stem cells, especially certain types of stem cells, “communicate” with the cells around them by producing cellular signals called cytokines, of which there are hundreds.
Cytokines trigger specific receptors on cell membranes that result in precise responses. This phenomenon is considered an essential element in the healing response of all tissues. Identifying and characterizing the large number of cytokines is an important part of stem cell research.
Not every induced response is necessarily beneficial. It is the “symphony” of responses that is important. How to promote helpful responses while inhibiting non-beneficial ones is a continuing focus of cellular biochemical research as well as the basis upon which drug companies spend huge resources developing drugs to either trigger or block particular cytokine receptors. Good examples in the field of dermatology are EGFR (epidermal growth factor receptor) blocking compounds for use in treating susceptible cells, most notably cancers stimulated by EGF.
Stem cell therapies hold potential to treat many conditions and diseases that affect millions of people in the U.S.
From the Laboratory to the Bedside
Going from the research laboratory to the bedside takes time. Only one month ago, the FDA granted marketing approval for the first licensed stem cell product. Derived from donated umbilical cord blood, the product contains stem cells that can restore a recipient’s blood cell levels and function. In the chart below, the type of cells recovered from umbilical cord blood are those designated as “HSC” cell. They are the exact cells responsible for the success of bone marrow transplantation.
Of particular note are the cells designated in the chart as “MSC” or mesenchymal stem cells. MSC cells are the focus of intense research in the treatment of a number of conditions because this type of stem cell can differentiate into a variety of cell types including bone, cartilage, muscles, nerve, and skin (fibroblast.)
Recent announcements about stem cells being used to fabricate “replacement parts” (bone, cartilage, heart muscle) are based on MSC research. They truly are the “duct tape” of the body’s repair tool box”; a phrase coined because of their importance in the healing of injuries.
Research has shown MSC cells reside in a number of tissues, including the bone marrow. Through precise chemical signaling that originate from sites of injury, MSC cells have the ability to become mobile, enter the blood stream and travel through the circulation to the injury. Upon arrival, MSCs orchestrate the healing response. Local resident stem cells are also called into action, to produce more stem cells or to produce needed tissue specific cells. In large part, MSCs accomplish their tasks bio-chemically.
Secreted cytokines have been identified as the major mechanism by which MSCs perform their important reparative functions. There are hundreds of cytokines identified thus far. The healing response is an intricate and balanced process in which many cytokines participate.
Despite their inherent ability to differentiate into essentially any type of cell, embryonic stem cells are unlikely to be a major research focus in the foreseeable future. Ethical and political considerations limit the acceptability of their use. Federal regulations permit research only on existing cell lines which are few in number. It is difficult to see how this prohibition will end any time soon.
Getting Closer but Not There Yet
MSC (mesenchymal stem cell) therapies include use of cells and use of MSC factors, the cytokines or chemical messengers mentioned above. Methods of administration will likely include intravenous infusion, injections into tissues or body spaces, or development of drugs that activate or block certain cytokine effects. Drugs already in development include epidermal growth factor receptor (EGFR) blockers for use in cancer treatment.
Stem Cells and Skin Health
From fetal life to death, the numbers and activity of stem cells diminish. The chart at left shows how the population of mesenchymal stem cells in the bone marrow dwindles with age.
Knowing that stem cells are important in producing differentiated daughter cells (such as fibroblasts within the dermis) and are instrumental in “orchestrating” the body’s response to injury, it is easy to understand how skin damage from sun exposure, gravity, smoking, trauma, toxins, even repetitive facial movement, accumulates over time.
This is one line of evidence (we will look at others) that mesenchymal stem cells (or more specifically the relative lack of same) has a lot to do with aging. Skin aging included.
Products Claiming to “Activate” Skin Stem Cells
The number of skin products claiming to “activate” human skin stem cells is large and growing. As discussed previously on BFT, a whole slew of plant derived “stem cell” products are being marketing, NONE of which can actually or theoretically activate anything, especially not a human stem cell.
Other products claim to have essential nutrients or antioxidants or some other “magical” ingredient that will suddenly make stem cells take notice and unleash their regenerative power. It is highly unlikely, except in the most extreme case of malnourishment, that any nutrient or antioxidant is deficient enough to cause a cell not to function.
These and the botanical stem cell products are marketing ploys. Human stem cells deep within the dermis will never know whether or not these substances are applied. Moisturizers and other recognized ingredients in these products can be beneficial to skin appearance…but not because a stem cell is involved.
This is worse than junk science. This is scamming.