The skin forms a barrier that protects us against dehydration and external threats. This barrier function is provided mainly by the outer skin layer, called the epidermis. This layer is constantly renewed; cells that are shed from the outer layer, the stratum corneum, are replaced by newly formed cells from the inner layer of the epidermis.
This constant renewal is important for the quality of the barrier and keeps the skin smooth and even. The epidermal turnover time is about 1 month. But between our thirties and eighties the turnover rate reduces by 30% to 50% leading to a much longer turnover time. The consequence of the slowdown of the renewal in elderly people is a dry, rough, uneven and dull skin.
Responsible for the constant renewal are epidermal stem cells that are dispersed in the inner layer of the epidermis. Only these cells have the potential to generate new cells for tissue renewal. But the rate of propagation of these cells is known to be reduced in elderly people. This is the principal reason for the reduced turnover rate and thus for the slowdown of the epidermis renewal with advancing age.
PhytoCellTec Symphytum activates the propagation rate of our epidermal stem cells. It thus restores the renewal potential of aged skin. PhytoCellTec Symphytum is an extract of comfrey stem cells. Comfrey is a perennial shrub with purple or pink flowers, native to Europe, growing in damp, grassy places. Comfrey is used as herbal medicine, mainly for skin treatments. Comfrey ointments are applied for wound-healing and the treatment of bone fractures.
The positive effect of the comfrey cell extract on the propagation rate of epidermal stem cells was discovered in a novel cell culture assay. To mimic the tissue environment of aged skin, a cell culture medium was developed that contained the essential elements but was devoid of protecting and stimulating compounds. The proliferation of isolated epidermal stem cells cultured in this ageing medium was clearly reduced compared to a normal medium. But epidermal stem cells cultured in the ageing medium supplemented with low amounts of the comfrey cell extract proliferated much more than in the control culture without comfrey cell extract. The comfrey cell extract was also found to improve morphology and hyaluronic acid content in epidermis models formed in the ageing medium.
Next, the comfrey cell extract was formulated into a vehicle cream and was tested in a clinical trial with 20 women, aged between 40 and 60. After 4 weeks’ application, a significant increase in the skin renewal rate was found. Concomitant, skin smoothness analysis by PRIMOS showed a 12% improvement.
As we get older, the skin renewal slows down leading to an uneven surface and the formation of scales. This has a negative influence on skin complexion and makes the skin look dull and grey. Instead of using irritating peeling procedures, Mibelle Biochemistry Group proposes PhytoCellTec Symphytum to get down to the root of the trouble