Inhibition of glucose-6-phosphate dehydrogenase activity by betamethasone and three of its esters with dermatological importance.

Betamethasone, betamethasone-17-valerate, betamethasone-17-benzoate, and betamethasone-17,21-diproprionate were investigated for their inhbitory action on glucose-beta-phosphate dehydrogenase (G-6-PDH) activity (pure enzyme from yeast, enzyme from human skin homogenate). Between these four compounds, marked differences were encountered which could not be attributed to the presence of an esterified or unesterified steroid. According to these data it does not seem to be justified to consider betamethasone esters simply as the transport forms of the topically inactive betamethasone but one must consider the betamethasone esters having biochemical actions of their own.