If there is an ‘it’ anti-aging ingredient for the past year, it is probably stem cells. Controversial in the fields of medicine and ethics, stems cells in cosmetics are equally complex. Anti-wrinkle serums based on stem cells may be derived from plants or humans. Some creams touting stem cells are simply being misleading. The Truth In Aging stem cell 101 tries to shed some light and stem (ahem) some of the misinformation.
A study on EGF taken from mice observed that it stimulated the growth of proteins in cells and hyaluronic acid in humans. However, it inhibited collagen production unless accompanied by vitamin C, in which case they “gave additive effects on growth and protein synthesis of the cells” (source). However, animal stem cells are not used in any of the cosmetics that I am aware of; they tend to come from either humans or plants.
Human fibroblast conditioned media
Human fibroblast conditioned media, or human adipose stem cells, or epidermal growth proteins appear in serums such as ReLuma’s or Osmosis StemFactor. So what are they and what is the process that got them into a cream.
The progenitor cells of the human fibroblast are typically taken from newborn baby foreskins (I can’t help thinking that there is a nice little sideline for rabbis here) or human fat – adipose - cells. In any case, they are called adult stem cells to differentiate them from embryonic stem cells, which are not used in cosmetics. From the progenitor cell, many thousands of new cells have been grown in the lab. Understanding this may help dispel myths (and fears) that new human cells are extracted for each batch of cosmetics and that they may be diseased or cancerous. The progenitor cell is supposedly pristine and then is cloned in a laboratory.
Conditioned media is, in fact, the solution (sugars, amino acids and such) that is put in the petri dish in which the cells are grown. Conditioned media might typically be thrown away by a lab that is using the cells for something else and this has led some people to worry (or to stir up rumors) that this ingredient is in fact waste. However, cosmetic companies such as SkinMedica or Reluma are not gathering up byproducts that are about to be thrown away. The conditioned media contains proteins that have been secreted by the cells and these proteins are what makes it into our serums.
ReLuma's formula uses adipose stem cells and conditioned media (as well as some other proprietary process). Osmosis StemFactor has conditioned media only.
There are many different proteins and, although they all send signals to cells, their roles differ. You’ll see that the various stem cell serums make claims about the number of proteins in serums and which are the most important. Osmosis claims over 100, and ReLuma counters with more than 300. In the end, I suspect that this is marketing speak and that what they really contain are families or groups of proteins (in which there may be 100s of sub proteins).
E’shee, for example, dotes on FGF-1 a family of growth factors involved in angiogenesis and wound healing. ReLuma is big on the TGF-b family (transforming growth factor-beta), saying it is considered the most important growth factor group because the majority of skin cells recognize their signals. TGF-b stimulates collagen production, promotes the synthesis of extracellular matrix proteins, and inhibits matrix degradation (thinning of your skin). ReLuma uses other growth factors including PDGF (Platelet-derived growth factor) and GM-CSF.
Mostly, these proteins are repairers and much of the research on them has been on wounds.
Plant stem cells
This year there are more and more anti-aging products with apple stem cells. But other plants are also being used for extracting growth factors, such as barley (Bioeffect). As far as I can make out, they are different from the proteins described above. There isn’t much research on what they do when in contact with human skin. As I wrote in my post on Juice Beauty’s new plant-derived stem cell formula, what makes plant derived stem cells so enticing is that they live forever.
According to Wikipedia, “plant stem cells never undergo aging process but immortally give rise to new specialized and unspecialized cells, and they have the potential to grow into any organ, tissue, or cell in the body”. British scientists found that plant stem cells were much more sensitive to DNA damage than other cells. And once they sense damage, they trigger death of these cells. Even so, harvesting their potent power is tricky; plant stem cells have to be taken from the meristem and some researchers concede that they aren’t that easy to locate.
The key question for me is how plant and human cells could possibly interact. From the reading I have done, they seem to have more in common than one might think. For example, one gene that is conserved between plants and animals has a central role in deciding whether a cell continues to divide or differentiates. (source). In animals, growth factor receptor kinases play key roles in cell differentiation and development, either by stimulating or inhibiting cell growth (source). EGF taken from animals has been shown to stimulate plant growth.
Faux stem cell serums
Jumping on the stem cell bandwagon are a number of potions and lotions that have never seen a whiff of the ingredients discussed in this post. One of these would be Stem Cell Therapy, and another called Amatokin claims it has a peptide that stimulates stem cells.
So if you see a potion touting stem cells, take a good look at the ingredients; there may not even be so much as a rose stem, let alone stem cells.