Dermal-epidermal junction: a key target for anti-ageing

It also behaves as a selective permeability barrier controlling cell migration (immune cells, for example), and molecular exchanges (growth factors and nutrients, stress signals). Epidermal cells’ interaction with the DEJ regulates their proliferation, differentiation and migration, which is critical for epidermal renewal, barrier function setup, and wound healing. 

Intrinsic and extrinsic ageing are associated with important DEJ structural modifications including flattening (loss of rete ridges),¹ duplication and thinning (Fig. 3b). At a molecular level, there is a decreased expression of the main DEJ constituent-proteins: collagens type IV, VII and XVII, laminin 5, and integrin b4.^2,3 All these changes likely participate in structural and functional changes associated with ageing skin (elasticity loss, higher fragility, decreased resilience to stress, impaired wound healing). In photoaged skin, degradation of some specific DEJ constituents such as heparan sulfate causes permeability modifications that were reported to participate in age spots formation.⁴ 

Therefore a large array of cosmetic benefits can be expected from DEJ protection and repair. Here we describe the properties of an original bioavailable rhamnose derivative, its mechanism of action, and clinical improvements obtained after four weeks of treatment.