title: The effect of l-thyroxine treatment on skin accumulation of acid glycosaminoglycans in primary myxoedema.
abstract: We assessed skin accumulation of acid glycosaminoglycans in ten patients with primary myxoedema (median age 70 years) before and during l-thyroxine treatment (median 7 months). Eight subjects matched for sex and age served as controls. Acid glycosaminoglycans were determined biochemically on small skin biopsies. Hyaluronic acid was elevated in untreated myxoedema, median 0.60, range 0.39-0.90 microgram hexosamine/mg dried defatted tissue compared to a median control value of 0.52, range 0.43-0.65 microgram hexosamine/mg dried defatted tissue, P less than 0.02. Chondroitin-4,6-sulphate and dermatan sulphate showed no elevation, while heparan sulphate was actually reduced in myxoedema, P less than 0.01. l-thyroxine treatment induced a significant reduction in hyaluronic acid, median 0.41, range 0.24-0.71 microgram hexosamine/mg dried defatted tissue, while no consistent changes occurred in the remaining three acid glycosamine glycans. The accumulation of hyaluronic acid might contribute to the peculiar non-pitting oedema of the skin in myxoedema, due to the strong water-binding capacity of the substance.
mesh_terms: D000328:Adult; D000368:Aged; D002809:Chondroitin Sulfates / Q000378:metabolism; D003871:Dermatan Sulfate / Q000378:metabolism; D005260:Female; D006025:Glycosaminoglycans / Q000378:metabolism*; D006497:Heparan Sulfate / Q000378:metabolism; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009230:Myxedema / Q000188:drug therapy* / Q000378:metabolism; D012867:Skin / Q000378:metabolism*; D013974:Thyroxine / Q000627:therapeutic use*
chemical_list: D002809:Chondroitin Sulfates; D003871:Dermatan Sulfate; D006025:Glycosaminoglycans; D006497:Heparan Sulfate; D006820:Hyaluronic Acid; D013974:Thyroxine