Use of urea compounds (I) or their salts, solvates or isomers in a cosmetic composition containing a medium, to prevent and/or decrease the signs of ageing of the skin and/or of the mucous membranes. Use of urea compounds (I) of formula (R 1)(R 2)N-CO-N(R 3)(R 4) or their salts, solvates or isomers in a cosmetic composition (II) containing a medium, to prevent and/or decrease the signs of ageing of skin and/or mucous membranes. R 1-R 4H, 1-4C alkyl or 2-6C hydroxyalkyl group (containing 1-5 OH). Provided that at least one of R 1-R 4 is a hydroxyalkyl group. ACTIVITY : Dermatological. MECHANISM OF ACTION : Proteolytic enzyme stimulator； Acid protease stimulator； Matrix metaloproteinase inhibitor； Plasminiogen activator inhibitor. The ability of (I) to stimulate acid protease was tested. The results showed that N(2-hydroxyethyl)-urea increased the activity to a concentration of 1-2 M compared to the control.
