A cosmetic and/or dermatological and/or pharmaceutical composition includes, as the active ingredient, at least one peptide with sequence X.sub.1-Y-Phe-Thr-X.sub.2-Ala-Thr-Z-Ile-X.sub.3-Leu-X.sub.4-Phe-Leu-X.sub- .5; wherein: X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5=Arg, Lys, His; Y=Asp, Glu; Z=Asn, Gln. The invention also relates to the use of said composition in order to treat, inter alia, the signs of cutaneous ageing. Moreover, the invention relates to the cosmetic skin treatment method using the peptide.