Effect of a novel steroid (PM-9) on the inhibition of 5α-reductase present in Penicillium crustosum broths

The conversion of testosterone (T) to 5-dihydrotestosterone (DHT) has been demonstrated in Penicillium crustosumbroth obtained from fermented pistachios, lemons and corn tortillas. Furthermore, the presence of 5-reductase enzyme, which is responsible for this conversion, has been established by electrophoretical techniques in these cultures. 5-Reductase enzyme is also present in animal and human androgen-dependent tissues as well as in prostate and seminal vesicles. The increase of the conversion of T to DHT in prostate gland, has been related to some illnesses such as benign prostate hyperplasia and prostate cancer. Furthermore, treatment with 5-reductase inhibitors such as finasteride reduces the prostate growth. These data have stimulated research for the synthesis of new molecules with antiandrogenic activity, whose biological effect needs to be demonstrated. The purpose of this study is to determine the inhibition pattern of 5-reductase in P. crustosum by finasteride and the new steroidal compound PM-9. Km and Vmax values for T, were determined in the broths by Lineweaver–Burk plots using different testosterone concentrations. The inhibition pattern of finasteride and PM-9 was also determined by Lineweaver–Burk using different concentrations of T and inhibitors. Results show that finasteride and PM-9 inhibit 5 -reductase present in the broth in a competitive manner. © 2002 Elsevier Science Inc. All rights reserved.