French cosmetic ingredients maker Gattefossé and research and product development firm BioMeca have collaborated to develop a 3D model of dermal microtissue to study elastic properties in vitro.
During ageing, human skin undergoes major biomechanical properties alterations, specifically a loss of elasticity that results in skin sagging.
Dermal elastic fibres, which support tissue resilience, undergo a decline in organisation and functionality over time, making them a primary anti-ageing target.
However, according to Gattefossé, existing 3D bioengineered skin substitutes are not effective for studying skin elasticity, as they typically contain exogenous and artificial matrices that can bias the measurement of biomechanical properties in reconstructed skin.
In response, 3D scaffold-free microtissues were developed by Gattefossé laboratories to mimic an elastic tissue in vitro.
To evaluate the elasticity of the microtissue, BioMeca provided analytical assessment.
“Characterising biological models is becoming a challenge to evaluate new formulas or active ingredients aiming to restore or maintain skin integrity,” commented the co-founder of BioMeca, Julien Chlasta.
“BioMeca offers state-of-the-art technologies to bring new insights biology. Second Generation Harmonic [SGH] microscopy highlights [the] fibres network while Atomic Force Microscopy [AFM] reveals tissue stiffness in both imaging and mechanically manipulating biological structures near physiological conditions overtime.
“With topographical mechanical measurement, quantitative nanomechanical quantification and tissue characterisation, BioMeca’s expertise represents a key for exploring elastic properties of skin models and opens a new door for skin care.”
3D scaffold-free spheroids take advantage of the ability of cells to secrete their own extracellular matrix to ultimately recreate their own microenvironment, which enabled Gattefossé to produce in vitro hundreds of 3D microtissues within a few days only using dermal fibroblasts aggregated in ultra-low affinity plates.
The elastic modulus (or Young modulus) was measured using AFM and the elastic fibres were visualised by Second Harmonic Generation (SHG) imaging microscopy.
Gattefossé and BioMeca therefore demonstrated the 3D spheroid microtissue to be a relevant and reliable model with a complex organisation, comprising a dense, mature elastic fibre network which can mimic dermal elastic mechanics.
“By combining two cutting-edge analytical techniques, ie Second Harmonic Generation microscopy and Atomic Force Microscopy, we have been able to accurately correlate both the presence and amounts of elastic fibres with elastic properties of microtissues, thus evidencing that newly formed elastic fibres were functional,” added Gattefossé’s Skin Biology Research Manager, Dr HDR Nicolas Bechetoille.
The new 3D model has been used to measure the efficacy of EleVastin, a novel active ingredient developed by Gattefossé to fight against age-related loss of skin elasticity, which is due to launch in April.
