CD Laboratory for Biotechnology of Skin Aging

It is well known that our skin cells age. But how exactly do these processes take place at the molecular biological level, how are they triggered and what accelerates or slows them down? Answers to these questions will also contribute to a better understanding of the biology of ageing in general.

The fact that cells only divide a limited number of times was already proven in cell cultures in the 1960s. The cells that were no longer able to divide were called senescent, i.e. "old" cells, as the number of divisions depends on the age of the donor and the lifespan of the species. Similarly, cells from patients suffering from premature signs of ageing (progeria) also have a shortened lifespan. Around the year 2000, it was finally shown that senescent cells do not only occur in Petri dishes, but also in living organisms. In the skin of older people, for example, it is estimated that up to 20% of cells are senescent.

These senescent cells are only able to function to a limited extent. In skin cells, for example, senescence leads to reduced elasticity, poorer wound healing and a deterioration in the skin's barrier function. The ability to defend against pathogens decreases and the release of signalling molecules that promote tumour formation is also possible.

The reasons for senescence lie in the genome of the cells (telomere shortening), but there are also stress-related triggers of premature senescence. UV light and free radicals are known stressors for skin cells, as are certain mutations in connection with cellular growth signalling.

This laboratory aims to understand how the molecular biological processes of skin ageing work in detail: Which molecules are released and when, where and how exactly do they work, what role do genes play and what other substances are involved?

As a result of a deeper understanding, proteins and micro-RNAs can then be sought that can delay senescence. We are also looking for substances - for example in plant extracts - that specifically render the senescent cells harmless while leaving the "young" cells that are still capable of dividing unaffected.

Methodologically, we mainly work with specially developed 3D cell cultures in which the ageing human skin and its horny layer (keratinocytes) are simulated in a petri dish. This model can be used to test the effects of plant extracts, proteins, enzymes, micro-RNAs and other factors in order to keep the skin youthful and healthy.