Hairloss Study Abstract: Inhibition of 5 alpha-reductase activity in human skin by zinc and azelaic acid.
Title
Inhibition of 5 alpha-reductase activity in human skin by zinc and azelaic acid.
Author
Stamatiadis D; Bulteau-Portois MC; Mowszowicz I
Address
Laboratoire de Biochimie B, Hôpital Necker-Enfants-Malades, Paris, France.
Source
Br J Dermatol, 119: 5, 1988 Nov, 627-32
Abstract
The effects of zinc sulphate and azelaic acid on 5 alpha-reductase activity in human
skin were studied using an in vitro assay with 1,2[3H]-testosterone as substrate. When
added at concentrations of 3 or 9 mmol/l, zinc was a potent inhibitor of 5 alpha-reductase
activity. At high concentrations, zinc could completely inhibit the enzyme activity.
Azelaic acid was also a potent inhibitor of 5 alpha-reductase; inhibition was detectable
at concentrations as low as 0.2 mmol/l and was complete at 3 mmol/l. An additive effect of
the two inhibitors was observed. Vitamin B6 potentiated the inhibitory effect of zinc, but
not of azelaic acid, suggesting that two different mechanisms are involved. When the three
substances were added together at very low concentrations which had been shown to be
ineffective alone, 90% inhibition of 5 alpha-reductase activity was obtained. If this
inhibition is confirmed in vivo, zinc sulphate combined with azelaic acid could be an
effective agent in the treatment of androgen related pathology of human skin.