P&G investigates gene expression in aging skin

Genomic analysis, looking at how genes are expressed, between young and old, sun-protected and sun-aged skin showed similar changes, according to P&G’s Dr Rosemarie Osborne.

“In both photoaged and intrinsically aged skin there is a decrease in antioxidant pathways, but there is an increase in pathways that generate oxidative stress,”​ she told CosmeticsDesign.

However, the changes to these pathways are more pronounced in photoaged skin than in naturally aged skin, she explained.

The research looked at the antioxidant response element (ARE) a family of enzymes and proteins under the control of the transcription factor NRF2 that help protect cells against oxidative damage.

This family of proteins can protect against the damage by increasing the concentration of antioxidants within cells and by up-regulating proteins that repair the damage done by reactive oxidative species.

According to the company, the transcription factor NRF2 was down-regulated in aging skin. In addition, markers of oxidative stress such as ceruloplasmin and clusterin were up-regulated as were genes related to hydrogen peroxide production.

Although in general the changes in gene expression were the same, just slightly less pronounced in intrinsically aged skin compared to photo-aged skin, there were some differences. And for Osborne this is where genomics analysis can really benefit as it allows researchers to understand the pathways in much more detail than has previously been possible.

It is even possible to tease out exactly how individual cell types will react to the aging process, she said.

Olive oil can help protect against oxidative damage​

The researchers then went on to investigate the effect of a number of topically applied ingredients on NRF2.

Olive oil derivatives (olive oil fatty acids modified with PEG-7 and olive oil blended with jojoba oil) and yeast ferment filtrate up-regulated the NRF-2 transcription factor in a dose-dependant way, according to the results which were presented at the recent annual meeting of the American Academy of Dermatology.

The company also found that combining the yeast ferment filtrate with the modified olive oil fatty acids enhanced the effects and concludes that research should focus on the complementary nature of these materials.