The invention relates to a method of treating with furanone derivatives and the pharmaceutically acceptable salts thereof, one or more conditions of the skin, in particular regulating skin condition, regulating signs of skin aging, treating a number of conditions such as contact dermatitis, skin irritation, rosacea, acne, psoriasis, and preventing and protecting skin tissue against age-related damage or damage resulting from insults such as harmful (UV) radiation or environmental pollution, stress and fatigue.