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From the Research
Metabolites of Testosterone
- 5α-dihydrotestosterone (5α-DHT) is a potent metabolite of testosterone, formed through the action of 5α-reductase enzymes 1, 2, 3
- Estradiol (E2) is another metabolite of testosterone, formed through aromatization 1, 2
- Androsterone and etiocholanolone are also metabolites of testosterone, which are excreted in urine and bile as glucuronides 4
- Dihydrotestosterone glucuronide (DHTG) is a major glucuronide metabolite of testosterone, which is primarily transported by MRP2 and MRP3 in human liver, intestine, and kidney 4
Formation and Transport of Metabolites
- The formation of 5α-DHT from testosterone is catalyzed by 5α-reductase enzymes, which are present in various tissues including the liver, kidney, and prostate 1, 2
- The transport of testosterone metabolites, such as glucuronides, is mediated by efflux transporters like MRP2, MRP3, MDR1, and BCRP 4
- The protein abundances of these efflux transporters vary in different tissues, including liver, intestine, and kidney, and influence the disposition of testosterone metabolites 4