Abstract: In the present specification is disclosed a melanocyte-stimulating hormone inhibitory composition which comprises, as the active ingredient, a di- or tripeptide derivative having a certain naphthyl group or the salts thereof, or a melanocyte-stimulating hormone inhibitory compound having a 50% inhibitory concentration of cAMP production (IC50) of 100 nM or less, which composition can prevent pigmentation, or can prevent, improve or recover from immune abnormality or immunodeficiency, or regulate body weight by appetite control, and also can be used as cosmetics or external preparations for the skin, and in addition, can be produced easily, and are excellent in the stability during storage.

Abstract: Objects of the present invention are to provide an oxidative stress inhibitor which is capable of suppressing the expression of a cytotoxic protein and the activation of a gene transcriptional regulatory factor taking part such expression of a cytotoxic protein and exhibits good feeling upon use and safety; to provide a method for preventing, retarding, alleviating or treating a skin change due to aging or an undesirable aesthetic skin change, both caused or promoted by an oxidative stress; and to provide a cosmetic composition or dermatologic preparation for external use comprising the oxidative stress inhibitor as an effective ingredient, and for those purposes are employed an oxidative stress inhibiting agent which comprises, as an effective ingredient, at least one selected from cysteine or cystine derivatives and the salts thereof.

Abstract: Objects of the present invention are to provide an oxidative stress inhibitor which is capable of suppressing the expression of a cytotoxic protein and the activation of a gene transcriptional regulatory factor taking part such expression of a cytotoxic protein and exhibits good feeling upon use and safety; to provide a method for preventing, retarding, alleviating or treating a skin change due to aging or an undesirable aesthetic skin change, both caused or promoted by an oxidative stress; and to provide a cosmetic composition or dermatologic preparation for external use comprising the oxidative stress inhibitor as an effective ingredient, and for those purposes are employed an oxidative stress inhibiting agent which comprises, as an effective ingredient, at least one selected from cysteine or cystine derivatives and the salts thereof.

Abstract: Objects of the present invention are to provide an oxidative stress inhibitor which is capable of suppressing the expression of a cytotoxic protein and the activation of a gene transcriptional regulatory factor taking part such expression of a cytotoxic protein and exhibits good feeling upon use and safety; to provide a method for preventing, retarding, alleviating or treating a skin change due to aging or an undesirable aesthetic skin change, both caused or promoted by an oxidative stress; and to provide a cosmetic composition or dermatologic preparation for external use comprising the oxidative stress inhibitor as an effective ingredient, and for those purposes are employed an oxidative stress inhibiting agent which comprises, as an effective ingredient, at least one selected from cysteine or cystine derivatives and the salts thereof.

Abstract: Objects of the present invention are to provide an oxidative stress inhibitor which is capable of suppressing the expression of a cytotoxic protein and the activation of a gene transcriptional regulatory factor taking part such expression of a cytotoxic protein and exhibits good feeling upon use and safety; to provide a method for preventing, retarding, alleviating or treating a skin change due to aging or an undesirable aesthetic skin change, both caused or promoted by an oxidative stress; and to provide a cosmetic composition or dermatologic preparation for external use comprising the oxidative stress inhibitor as an effective ingredient, and for those purposes are employed an oxidative stress inhibiting agent which comprises, as an effective ingredient, at least one selected from cysteine or cystine derivatives and the salts thereof.

Abstract: Provided are an anti-inflammatory agent containing, as an active ingredient, at least one selected from amino acid derivatives represented by formula (I) wherein Ar represents an optionally substituted 2-hydroxyaryl group, n is 0 or 1, R2 represents a hydrogen atom or a side chain of an &agr;-amino acid or &bgr;-amino acid, X represents —O— or —NH—, R1 represents a hydrogen atom or a group that forms, together with R2 and an adjacent atoms, a cyclic structure of pyroglutamic acid, and R3 represents a hydrogen atom, an alkyl group having from 1 to 22 carbon atoms or an alkenyl group having from 2 to 22 carbon atoms, and salts thereof, and toiletries or skin external products containing the same. The anti-inflammatory agent of the invention inhibits expression of an inflammatory protein and activation of a gene transcription control factor that participates therein, and exhibits a good feeling upon use and a safety.

Abstract: Objects of the present invention are to provide an oxidative stress inhibitor which is capable of suppressing the expression of a cytotoxic protein and the activation of a gene transcriptional regulatory factor taking part such expression of a cytotoxic protein and exhibits good feeling upon use and safety; to provide a method for preventing, retarding, alleviating or treating a skin change due to aging or an undesirable aesthetic skin change, both caused or promoted by an oxidative stress; and to provide a cosmetic composition or dermatologic preparation for external use comprising the oxidative stress inhibitor as an effective ingredient, and for those purposes are employed an oxidative stress inhibiting agent which comprises, as an effective ingredient, at least one selected from cysteine or cystine derivatives and the salts thereof.