A Tissue Model of Wrinkle Formation

A good tissue model tends to speed up research to the degree that it is less costly and easier to manage than animal models. This is especially true of age-related conditions, as the animal models tend to require a supply of aged animals, which is relatively expensive in terms of time and cost when compared with maintaining a supply of young animals. It is a little early to say whether the model of wrinkle formation noted here is a good tissue model, whether it adequately replicates the mechanisms of wrinkle formation in real tissue. There is sufficient interest in skin aging to ensure that the model will be assessed rigorously in the years ahead, however.

Despite the significance of biological wrinkle structures, much of the research in this area has relied on animal models including fruit flies, mice, and chickens, due to limitations in replicating wrinkle formation in vitro. As a result, the detailed processes behind wrinkle formation in living tissue remain largely unknown. Researchers addressed this limitation by developing an epithelial tissue model composed solely of human epithelial cells and extracellular matrix (ECM). By combining this model with a device capable of applying precise compressive forces, they successfully recreated and observed wrinkle structures in vitro that are typically seen in the gut, skin, and other tissues in vivo. This breakthrough allowed them, for the first time, to replicate both the hierarchical deformation of a single deep wrinkle caused by a strong compressive force and the formation of numerous small wrinkles under lighter compression.

The team also discovered that factors such as the porous structure of the underlying ECM, dehydration, and the compressive force applied to the epithelial layer are crucial to the wrinkle formation process. Their experiments revealed that compressive forces deforming the epithelial cell layer caused mechanical instability within the ECM layer, resulting in the formation of wrinkles. Additionally, they found that dehydration of the ECM layer was a key factor in the wrinkle formation process. These observations closely mirrored the effects seen in aging skin where dehydration of the underlying tissue layer leads to wrinkle development, providing a mechanobiological model for understanding wrinkle formation.

Link: https://www.postech.ac.kr/eng/the-mystery-of-human-wrinkles-what-do-the-cells-say/