Everyone wants to cash in on the excitement surrounding stem cells. This week, Bryn Nelson reports on how this is playing out in high-end skin products (A superficial success).
Other stories about companies that market products directly to consumers include Stem-cell banking: lifeline or sub-prime? and several articles on the unregulated clinics offering more hope than evidence in their promises to cure serious diseases: (Stem cell researchers face down stem cell tourism, Offshore stem cell treatments and Stick to the guidelines and fewer get hurt).
I commissioned the cosmetics feature after receiving an advertisement for a ‘FROZEN STEM CELL FACIAL’ (Perhaps it works better in ALLCAPS). I called the spa and asked where the cells were from. “Paris,” came the reply. I was told they were “bovine” upon further query. Shortly thereafter, I received an e-mail from DeCouverte Cosmetique advertising a skin product that promised to give my skin the “post-conception glow” of pregnant women. The secret ingredient? Tropoelastin, a chemical from embryonic stem cells. (Never mind that since embryonic stem cells come from pre-implantation blastulas, pregnant women don’t receive any chemicals from these cells.) The advertisement continued, stating that “the product may cause some controversy because the active ingredient is sourced from human embryonic stem cells.” I’d asked Bryn to contact the spa as well as DeCouverte, but neither responded to multiple requests to talk to a reporter.
Intrigued by tropoelastin, I went to PubMed to see who had actually studied this mysterious compound. This led me quickly to Robert Mecham of Washington University in Saint Louis, Missouri, who kindly indulged my questions.
Q: Is there evidence that tropoelastin has antiaging properties? Is there any evidence that it is responsible for ‘post-conception glow’?
A: There is no evidence whatsoever that tropoelastin has antiaging properties. In tissues, tropoelastin gets rapidly cross-linked to form elastic fibres, which are what makes tissues like lung, blood vessels and, to a lesser degree, skin, elastic. Elastic fibres are completely insoluble and are not made after puberty. Adding tropoelastin to skin, etc. does not increase the amount of elastic fibres in the tissue. In fact, tropoelastin cannot even cross the skin epithelial layer. I’m not sure what ‘post-conception glow’ is, but it doubt that it has anything to do with elastin.
Q: Would tropoelastin produced by human embryonic stem cells be any different from tropoelastin produced by other mammalian cells?
A: No, there is only one tropoelastin gene, and it is the same in all cells. I also doubt that stem cells make enough tropoelastin to be of practical use in cosmetics — it is not expressed well in cultured cells and is difficult to purify. Furthermore, I doubt that stem cells even express elastin. In tissues like the lung, blood vessels and skin, elastin is not expressed until quite late in development. There is no reason that it should be expressed in early, undifferentiated cells.
As far as I know, there is no scientific proof that any of the extracellular matrix proteins (collagen, elastin, tropoelastin, glycosaminoglycans) that get included in skin creams have any effect whatsoever.
I’d be happy to see any evidence of efficacy, and I’m curious which people find funnier. A frozen stem cell facial or post-conception glow?