Methods and compositions for improving the appearance of skin

A method for stimulating collagen synthesis in skin cells in need of such treatment by topically applying a composition comprising at least one extract from Laminaria genus, at least one extract from the Narcissus genus, and at least one peptide of the formula (I):

• R1-(AA)n-X1-X2-X3-X4-X5-X6-(AA)p-R2, in which
• X1 is glycine or threonine or histidine;
• X2 is alanine or glutamine or glycine;
• X3 is glycine or asparagine or serine;
• X4 is valine or isoleucine or leucine;
• X5 is serine or aspartic acid or phenylalanine;
• X6 is alanine or glutamic acid or lysine;
• wherein
• when X1 is glycine, then X2 is alanine and X3 is glycine;
• when X1 is threonine, then X3 is asparagine;
• when X1 is histidine, then X2 is glycine;
• AA represents any amino acid and n and p are integers between 0 and 2;
• R1 represents the primary amino function of the N-terminal amino acid, free or substituted by an acyl type group having either an alkyl chain from C1-30, saturated or unsaturated, that may be an acetyl group, or an aromatic group that may be chosen from among a benzoyl, tosyl or benzyloxycarbonyl type group;
• and
• R2 represents the hydroxyl group of the carboxyl function of the C-terminal amino acid, free or substituted by a group that may be chosen from among an alkyl chain from C1-30, or an NH2, NHY or NYY group with Y representing an alkyl chain from C1-4 wherein the extract from the Laminaria genus is present at 0.001 to 1%, the extract from Narcissus genus is present at 0.001 to 1.5% and the peptide is present from 0.0001 to 1%, with all percentages by weight of the total composition.