Abstract: Topically applicable dermocosmetic compositions for combating the clinical signs of skin aging and/or for improving the appearance of the skin, the scalp or the hair, comprise an anti-free-radical effective amount of at least one novel melatonin derivative having the structural formula (I): ##STR1## in which R.sub.1 is a lower alkyl radical, R.sub.2 is a hydrogen atom or a lower alkyl radical, and R.sub.3 is a hydrogen atom or a lower acyl radical, with the proviso that the hydroxyl radical is in the 4-, 6- or 7-position on the indole ring system, or a physiologically acceptable salt, solvate or bioprecursor/prodrug thereof, formulated into a topically applicable, cosmetically/dermatologically acceptable vehicle, carrier or diluent therefor.

Abstract: Topically applicable dermocosmetic compositions for improving or maintaining the appearance of human skin or the scalp, comprise a minor antioxidant effective amount of melatonin or analog thereof, formulated into a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor, such minor antioxidant effective amount being less than 10.sup.-4 % by weight relative to the total weight thereof, e.g., no greater than 0.5.times.10.sup.-4 % or ranging from 10.sup.-12 % to 10.sup.-15 % by weight thereof.

Abstract: Topically applicable dermocosmetic compositions for whitening/depigmenting human skin, comprise a skin-whitening/depigmenting effective amount of at least one melatonin derivative having the structural formula (I): in which R.sub.1 is a lower alkyl radical, R.sub.2 is a hydrogen atom or a lower alkyl radical, and R.sub.3 is a hydrogen atom or a lower acyl radical, with the proviso that the hydroxyl radical is in the 4-, 6- or 7-position on the indole ring system, or a physiologically acceptable salt, solvate or bioprecursor/prodrug thereof, formulated into a topically applicable, cosmetically/dermatologically acceptable vehicle, carrier or diluent therefor.

Abstract: A cosmetic or dermatological composition containing a mixture of at least one type-III ceramide in the form of a single stereoisomer and of at least one type-V ceramide. This mixture is in particular a mixture having a melting point which is much lower than that of the type-III ceramide. This composition is intended in particular for moisturizing dry skins.

Abstract: Moisturizing composition for the simultaneous treatment of the surface layers and deep layers of the skin, and use thereof. The composition of the invention comprises a first dispersion of lipid vesicles which are capable of penetrating into the deep layers of the skin and which contain at least one active agent selected from the group consisting of polyols, sugars, proteins, vitamins and the derivatives thereof, ceramides, essential fatty acids, and sterols, for treating these deep layers, and a second dispersion of lipid vesicles which are capable of penetrating into the surface layers of the skin and which contain at least one active agent selected from the group consisting of polyols, nitrogen-containing carboxylic acid derivatives, keratolytic agents, inorganic salts and lipoamino acids, for treating these surface layers.