The present invention relates to a peptide of general formula (I):R1-(AA)n-X1-Gly-Glu-Leu-Ser-X2-X3-(AA)p-R2, derived from human HMG-CoA reductase. The present invention also relates to a cosmetic or pharmaceutical composition comprising at least one peptide of general formula (I), in a physiologically suitable medium.The present invention further relates to the use of this novel peptide as an active principle that activates human HMG-CoA reductase in a cosmetic composition intended to strengthen the barrier function of the skin and to stimulate epidermal differentiation. The invention further applies to a cosmetic treatment method intended to prevent and/or combat the external stresses and signs of cutaneous aging.
