Depigmentary effect of lichen compounds

Context: Lichens are evolutionary conserved symbiotic organisms of fungi and algae. These poorly studied organisms develop and survive under harsh climate including UV-exposure. Lichens present various colours: white, black red according to the species and metabolite localizations. Researchers made the hypothesis that lichens may produce original compounds that may modulate pigmentation.

Results: Extract from the lichen, Cetrariaislandica was proved to modulate pigmentation. One active molecule has been identified to down regulate pigmentation. It is a unique lichen structure : aliphatic lactone.

This aliphatic lactone can be synthetized in 7 steps. Starting from this active compound, derived molecules have been synthetized in an enantioselective manner. Two of them induce higher depigmentation. These tests have been performed using pigmented cell lines (MNT1, B16) and cultured  human skin explants (Nativskin® ).

No toxicity has been detected

Depigmentation effect was higher than the one induced by control molecules (hydroquinone, arbutin) with a 20% reduction of the melanin content.

Electronic microscopy imaging demonstrate that the molecule acts on melanosomes, the melanin producing organelle. Structure/function analysis predicts that this molecule may interact with a melanosomal receptor.

Application: This molecule presents high skin depigmentation activity and is proposed to be active for skin whitening and for treating hyper-pigmented disorders like melasma.