CONCLUSIONS
In this model,
– TESTO is an active androgen by itself and is converted into DHT through the activity of type 1 5-alpha reductase. DHT direct androgenic activity is achieved at concentrations 10-fold lower than TESTO. Other metabolites are also formed such as –dione metabolites which exhibit a low but significant androgenic activity (> 10-fold less active than TESTO).
– DHEA is totally inactive by itself. It is not transformed into TESTO and 3bHSD expression was not detected. DHEA is very slowly metabolized into androsterone and other discrete species. Androsterone is moderately active by itself (> 10-fold less active than TESTO) and could explain the low activity of DHEA in long term assays.
– An excess of DHEA did not interfere with Testo metabolism and DHT production, nor with the androgenic activity of DHT, thus it cannot be considered as a “competitor” of TESTO.
REFERENCES
1 Barrault et al. (2015) J Steroid Biochem Mol Biol ;152:34-44
2 Bernard et al. (2000) Int J Cosmet Sci ;22:397-407
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