The present invention relates to the use, especially the cosmetic and/or therapeutic use, of the protein DJ-1, of polypeptides derived from this protein or of analogs thereof, of a nucleic acid sequence coding for such a polypeptide or of a modulator of the activity, stability or expression of such a polypeptide, especially for preventing and/or treating the signs of skin dryness. The invention also relates to the use of the protein DJ-1, of polypeptides derived from this protein or of analogs thereof or of a nucleic acid sequence coding for such a polypeptide, as a marker for evaluating the state of dryness of an epithelium.