Background: It is well known that male-pattern baldness (MPB) is not started from occipital, but frontal or scalp of head. We can assume that distribution of androgenic steroids is different for each region of the head.
Objective: We hypothesize that the levels of androgenic steroids are different not only between vertex hair with MPB and controls but also between occipital hair with MPB and controls. Moreover, we want to search for the biochemical indicator in plasma and hair sample (baldness: 22, non-baldness: 13) obtained from dermatology of medical center. After then, we desire to present fundamental data regarding diagnosis, medical cure, and prevention for premature MPB.
Methods: After hair and plasma were hydrolyzed, and then extracted with organic solvent. To assess androgenic steroids levels, we used gas chromatography-mass spectrometry (GC-MS) system in selected ion monitoring mode.
Results: The level of dihydrotestosterone (DHT) and the ratio of testosterone to epitestosterone (T/E ratio) in vertex hair from premature baldness subjects were higher than in the sample of non-baldness subjects (P<0.001, 0.001), whereas the levels of androgens in occipital hair from the same baldness group were not different. In addition, we discovered the levels of DHT, testosterone, and DHT/T ratio in plasma from premature MPB were higher than in those of control subjects (P<0.001, 0.001, 0.005).
Conclusion: We verified that the distribution of androgenic steroids is unlike in various regions of individual subjects. Moreover, the increased DHT/T ratio in balding plasma indirectly confirms the high activity of 5alpha-reductase type II.