tretinoin and Amyloidosis

Topics: Administration, Topical; Amyloidosis; Azathioprine; Clinical Trials as Topic; Colchicine; Dimethyl Sulfoxide; Double-Blind Method; Etretinate; Humans; Skin Diseases; Tretinoin

Lichen amyloidosis and macular amyloidosis are commonly therapy-resistant. Tocoretinate is a hybrid compound of retinoic acid and tocopherol that is commonly used for the treatment of skin ulcers. Although beneficial effect of oral retinoic acid on lichen amyloidosis is reported, tocoretinate has not been reported to be useful for the treatment of lichen amyloidosis or macular amyloidosis. We evaluated the effects of topical tocoretinate on lichen amyloidosis and macular amyloidosis lesions. Tocoretinate was topically applied daily to the lesions and clinical improvement and histological changes were evaluated. The outcome was very good for four, good for two, moderate for two and poor for two of 10 treated patients. Epidermal hypertrophy was reduced and expression of involucrin, keratin 1 and keratin 10 was decreased by tocoretinate treatment, suggesting the normalization of epidermal differentiation. Amyloid deposits remained histologically detectable, even in clinically responsive patients. Together, topical application of tocoretinate reduced the clinical symptoms of lichen amyloidosis and macular amyloidosis, and normalized disturbed epidermal differentiation.

Topics: Administration, Topical; Adult; Aged; Amyloidosis; Dermatologic Agents; Drug Combinations; Female; Humans; Male; Middle Aged; Treatment Outcome; Tretinoin; Vitamin E; Young Adult

Male Syrian golden hamsters received 12 weekly intratracheal exposures to 0.5% N-methyl-N-nitrosourea with a special catheter. Following exposures, animals were randomized into 4 groups of 63 hamsters and placed on diets of lab meal or meal with 120 mg 13-cis-retinoid acid (CRA)/kg, 327 mg ethyl retinamide (ER)/kg, or 343 mg N-(2-hydroxyethyl)retinamide (HR)/kg for 6 months at which time all hamsters were killed. The observed incidences of tracheal epithelial neoplasms (No. of animals with tumors/total No. of animals) were 10/63 (lab meal), 22/61 (CRA), 24/63 (ER), and 17/62 (HR). The incidence of carcinomas (No. of animals with tumors/total No. of animals) were 4/63 (lab meal), 12/61 (CRA), 12/63 (ER), and 11/62 (HR). The weight loss and mortality relative to those in the group fed the lab meal were significantly in the group fed HR but not in the other retinoid-treated groups.

Topics: Amyloidosis; Animals; Carcinoma; Cricetinae; Isotretinoin; Male; Mesocricetus; Methylnitrosourea; Neoplasms, Experimental; Precancerous Conditions; Probability; Tracheal Neoplasms; Tretinoin