A peptide of general formula (I) R1-Wp-Xn-AA1-AA2-AA3-AA4-Ym-R2 (I) its stereoisomers, mixtures thereof and / or their cosmetically or pharmaceutically acceptable salts, characterized in that at least one of the amino acids AA1, AA2 or AA4 is not encoded, and because: AA1 is selected from the group consisting of -Arg-, -Phg- and -Nle-, or is a bond; AA2 is selected from the group consisting of -Ala-, -Phg-, -Cit- and -Nle-; AA3 is selected from the group consisting of -Trp-, -Val- and -Tyr-; AA4 is selected from the group consisting of -Phg- and -Gly-; W, X and Y are independently selected from the group consisting of encoded or uncoded amino acids; p, n and m ranges between 0 and 1; R1 is selected from the group consisting of H, substituted or unsubstituted non-cyclic aliphatic group, substituted or unsubstituted alicyclyl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted heteroarylalkyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl and R5 -CO-; R2 is selected from the group consisting of -NR3R4, -OR3 and -SR3; wherein R3 and R4 are independently selected from the group consisting of H, substituted or unsubstituted aliphatic group, substituted or unsubstituted alicyclyl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted heteroarylalkyl, substituted or unsubstituted aryl and aralkyl substituted or unsubstituted; wherein R5 is selected from the group consisting of H, substituted or unsubstituted non-cyclic aliphatic group, substituted or unsubstituted alicyclyl, substituted or unsubstituted aryl, substituted or unsubstituted aralkyl, substituted or unsubstituted heterocyclyl and substituted or unsubstituted heteroarylalkyl replaced; and with the proviso that when AA1 is a link, AA2 is -Phg- and AA3 is -Trp-.Un péptido de fórmula general (I) R1-Wp-Xn-AA1-AA2-AA3-AA4-Ym-R2 (I) sus estereoisómeros, mezclas de los mismos y/o sus sales cosmética o farmacéuticamente aceptables, caracterizado por que al