How daily exposure to blue light accelerates skin aging in impacting dermis mechanical properties ?

Light is necessary for life, but long exposure to artificial light is becoming a major health concern.

Humans are exposed to increased amounts of light in the blue spectrum produced by light-emitting diodes (LEDs) found in screens and smartphones which can interfere with biological processes.

The LED technologies are relatively new and the long-term effects of exposure to blue light across the lifespan are not yet understood.

DermoMeca®‘s solutions

DermoMeca® proposes to study physical behavior of fibroblasts, cells responsible for collagen and elastin synthesis, and dermis sustaining capacity.

Biological models :

• in vitro models : cells grown on collagen lattice
• ex vitro models : reconstructed skin models, skin explants, etc.

Readouts :

• Cell morphometry (area, perimeter, circularity, aspect ratio, etc.)
• Cell mechanical properties (stiffness, elastic modulus, traction force)
• Morphometric parameters of collagen network (fiber density, fiber thickness, fiber orientation)
• Morphometric parameters of collagen fibers (thickness, period measurement, etc.)
• Network mechanical properties (tension, strain stiffening)

Figure 1 : A. AFM topographical image of collagen I polymerized during 18h.

B. AFM topographical image of collagen I polymerized during 18h under blue light (800J/cm²).

C. Analysis of collagen I fibers tickness on both conditions.

D. Elastic modulus of collagen I lattice in both conditions.

CONCLUSION

Blue light irradiation has a significant effect on collagen network architecture in terms of structure and mechanical properties. Collagen fibers are thinners when they are exposed to blue light during polymerisation process. Moreover the stiffness of the collagen lattice increases as function of blue light long-time exposure.