Sebaceous gland activity and urinary androgen levels in children

Sebum and 24-h urine samples were collected from 17 children, aged 10-17 years. Wax ester (WE) secretion rates were measured as the index for sebaceous gland activity. The fatty acid methyl esters were analyzed by capillary gas chromatography. Urinary testosterone as well as 17-ketosteroids (androsterone, dehydroepiandrosterone (DHEA), and etiocholanolone) were separated from the urine samples and analyzed by gas chromatography. WE secretion rates increased with age and there were correlated changes in the monounsaturated fatty acids of WEs. Straight chain types such as 14:1 and 16:1 tended to increase, while 18:1 tended to decrease. There was a negative correlation between iso even fatty acids and WE secretion rates. However the other chain types such as straight odd, iso odd and anteiso odd showed no statistically significant change in relation to WE secretion rates. WE secretion rates were correlated positively with testosterone levels in both sexes, with DHEA in males, and with etiocholanolone in females. The results suggest that sebaceous gland activity is stimulated by adrenocortical androgens in prepuberty, in addition to the strong effect of testosterone during puberty.