New research reveals mechanisms behind skin ageing
The doctoral dissertation highlights the consequences of UVB exposure on the enzyme catalase found in the skin barrier, as well as the effects on the tissue surrounding the enzyme.
Methods to measure enzyme activity in layers of the skin have been refined by doctoral student Michal Szczepanczyk. His studies contribute to a better understanding of the skin's antioxidant defences and how different factors, such as UV radiation, affect these protective mechanisms that promoting healthy skin.
Enzymes are a type of proteins that speed up chemical reactions in the body without being consumed themselves. A common cause of skin disorders is oxidative stress.
The results show that exposing the skin to ultraviolet radiation, which can inactivate antioxidant enzymes, radically weakens the skin's defence mechanism.
Michal Szczepanczyk
“Antioxidant enzymes work by protecting cells against damage caused by free radicals and reactive oxygen species (ROS) and are a natural defence against such oxidative stress,” explains Szczepanczyk.
In his thesis, Szczepanczyk investigated the protein catalase and its antioxidant function in the different layers of the skin; he also improved an electrochemical measurement method to make it more suitable for complex biological samples outside the body. He showed that the electrochemical method can be used to advantage for biological samples from the outer layer of the skin (stratum corneum) in the epidermis.
It is widely recognised that ultraviolet radiation (in this case UVB) can impair skin health, including causing premature skin ageing. However, the mechanisms underlying these skin damages from ultraviolet radiation are not fully understood.
In the thesis – Refinement of in vitro measurements of skin enzymes: Catalase function and UVB effects and regulation of ECM protein degradation by elastase and collagenase – the consequences of UVB exposure on the enzyme catalase found in the skin barrier and the effects on the tissue surrounding the enzyme are analysed.
“The results show that exposing the skin to ultraviolet radiation, which can inactivate antioxidant enzymes, radically weakens the skin's defence mechanism,” says Szczepanczyk.
The dermis is located between the epidermis (the outermost layer) and the hypodermis (the innermost layer) and contains collagen and elastin, which contribute to the skin's durability and elasticity. Increased activity of proteases (proteins that break down other proteins) can be harmful to the dermis and contributes to skin ageing.
One aim of the project was to develop simple models of collagen and elastin, similar to the extracellular matrix ECM, to investigate how the matrix is affected by proteolytic activity.
“The results show that collagen and elastin form biological thin films with different properties, collagen forms slightly thicker and softer films while elastin forms thin and rigid films. This is knowledge that in the future can contribute to a better understanding of different disease processes,” says Szczepanczyk.
ComBine
The research in this thesis was conducted within the project ComBine - the industrial graduate school of Biofilms and Biointerfaces, with funding from the Knowledge Foundation. An overall goal of ComBine is to train researchers with interdisciplinary knowledge in biofilms and biointerfaces. The thesis also includes unpublished results from research conducted in collaboration with Simris Group AB, with the aim of evaluating algae residues as a potential source of bioactive compounds that can promote skin health.
