The Production of Hyaluronidase (Hyaluronate Lyase) by Corynebacterium Acnes

This paper presents evidence of the production of hyaluronidase by Corynebacterium acnes. In a study of seven random isolates of C. acnes from lesions of cystic acne and from normal skin, hyaluronidase activity ranged from less than one turbidity reducting unit (TRU) to 72 TRU per mg of extracellular protein. These findings raise the interesting possibility that C. acnes hyaluronidase may play a role in the development of acne by contributing to the inflammatory phase through an increased permeability of the follicular epithelium to free fatty acids and other irritants

Effect of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin on Murine Skin

The effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on skin of congenic haired and hairless newborn and adult HRS/J mice was studied. In all adult animals topical application of TCDD caused an involution of sebaceous glands. Epidermal/epithelial hyperplasia and hyperkeratinization was induced in the hairless, but not the haired mice. Transglutaminase (TG) activity was stimulated in both haired and hairless animals. A single application of 1 μg of TCDD did not stimulate significant ornithine decarboxylase activity in the skin in either strain. Other than a reduction in the density of the inflammatory cell infiltrate in the dermis, topical treatment with antiinflammatory agents fluocinolone acetonide and indomethacin did not affect the cutaneous response to TCDD. Skin of newborn mice treated topically with TCDD over a 2-wk period reacted much the same as adult skin in that sebaceous glands were reduced in size and TG activity was stimulated in both haired and hairless neonates; but epidermal hyperplasia occurred only in the hairless, not the haired newborns