title: Axillary 5 alpha-androst-16-en-3-one, cholesterol and squalene in men; preliminary evidence for 5 alpha-androst-16-en-3-one being a product of bacterial action.
abstract: Twenty-four hour axillary levels of the odorous steroid 5 alpha-androst-16-en-3-one, have been measured in six men by radioimmunoassay. Initially, no control of bacterial activity was made and conditions attempting a normal axillary environment were maintained. The level of 5 alpha-androst-16-en-3-one was significantly higher (P = 0.028) in one axilla ("superior") than the other ("inferior") and levels showed considerable variation both between and within individuals. This difference between axillae was also observed for cholesterol (P = 0.0013) but not for squalene (P = 0.18). This suggests that the presence of 5 alpha-androst-16-en-3-one in the axilla does not correlate with sebum secretion. The effect of a general germicidal agent was tested by shaving and applying Povidone-iodine to the "superior" axilla whilst treating the "inferior" axilla as a control. A highly significant drop in the level of 5 alpha-androst-16-en-one in the "superior" axilla below that in the control axilla was obtained (P = 0.000014, double tailed, as calculated using the Fisher Exact test). Squalene and cholesterol were measured in an attempt to monitor glandular activity and their levels were not significantly affected by Povidone-iodine. It is likely, therefore, that the production of 5 alpha-androst-16-en-3-one is from metabolism of a percursor in the axillae by skin micro-organisms.
mesh_terms: D000736:Androstenes / Q000032:analysis*; D001365:Axilla / Q000187:drug effects / Q000378:metabolism / Q000382:microbiology*; D002784:Cholesterol / Q000032:analysis*; D006801:Humans; D008297:Male; D011206:Povidone-Iodine / Q000494:pharmacology; D013185:Squalene / Q000032:analysis; D013542:Sweat / Q000032:analysis*
chemical_list: D000736:Androstenes; C000214:androst-16-en-3-one; D013185:Squalene; D011206:Povidone-Iodine; D002784:Cholesterol