naphthoquinones and Pruritus

Topics: Adult; Allergens; Cymbopogon; Dermatitis, Allergic Contact; False Negative Reactions; Female; Humans; Naphthoquinones; Oils, Volatile; Patch Tests; Phenylenediamines; Pruritus; Skin; Tattooing

The antipruritic effects of orally administered 1,4-naphthoquinone derivatives and related compounds on compound 48/80-induced scratching behavior in mice were studied. 2-Hydroxy-3-(2-hydroxyethyl)-1,4-naphthoquinone, ferulic acid, 2,2'-methylenebis(3-hydroxy-1,4-naphthoquinone), and 2,2'-ethylidenebis(3-hydroxy-1,4-naphthoquinone) (impatienol) all exhibited significant antipruritic activity. However, 2-methoxy-3-(2-hydroxyethyl)-1,4-naphthoquinone (balsaquinone), which was isolated from a natural source for the first time, did not show any activity. The present results indicate that these compounds are promising for treating allergic diseases with chronic and severe pruritus.

Topics: Animals; Antipruritics; Magnetic Resonance Spectroscopy; Male; Mice; Naphthoquinones; p-Methoxy-N-methylphenethylamine; Plants, Medicinal; Pruritus; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet

We examined the effects of a 35% ethanol extract (IB) from the petals of Impatiens balsamina L. and the principal active compounds from IB on chronic and serious pruritus and the development of dermatitis using NC mice, a model of atopic dermatitis. IB at 100 mg/kg significantly inhibited serious scratching behaviour in the NC mouse with established dermatitis when administered i.v. 1 h before, or p.o. 24 h before the measurement. A 10 microg/kg dose of kaempferol 3-rutinoside and 2-hydroxy-1,4-naphthoquinone (lawsone) isolated from IB also inhibited scratching behaviour in the NC mouse with established dermatitis. When 4-week-old NC mice with no symptoms were administered orally 100 mg/kg/day of IB until 13 weeks of age, protection was also noted against scratching behaviour during the development of dermatitis. IB was effective for the prevention and treatment of atopic dermatitis.

Topics: Animals; Antipruritics; Behavior, Animal; China; Dermatitis, Atopic; Disease Models, Animal; Drugs, Chinese Herbal; Glucosides; Impatiens; Male; Mice; Mice, Inbred Strains; Naphthoquinones; Phytotherapy; Plant Extracts; Plant Structures; Plants, Medicinal; Pruritus; Quercetin

Topics: Administration, Topical; Adult; Anti-Inflammatory Agents; Coloring Agents; Dermatitis, Allergic Contact; Humans; Hydrocortisone; Male; Naphthoquinones; Patch Tests; Phenylenediamines; Pruritus; Tattooing