In the field of cosmetics or pharmaceuticals, and particularly to the dermatological field, disclosed are particles containing hyaluronic acid modified by hydrophobic groups and the use thereof as an agent for stimulating the epidermis and/or dermis. In particular, the assemblies are useful on the one hand, as a moisturising and/or plumping and/or volumising agent. On the other hand, the particles containing hydrophobised hyaluronic acid are useful for reactivating endogenous hyaluronic acid expression thereby making it possible to reduce and/or prevent skin imperfections such as filling in wrinkles and lines.
