Estrogen Metabolism

Enzymes are key in estrogen production

Aromatase Enzyme Converts Androgens to Estrogens

ANDROSTENEDIONE ➔  ESTRONE (in women)

TESTOSTERONE ➔  ESTRADIOL.

Aromatase can be found in several tissues:

-   Tissues having beneficial estrogen presence.  Includes gonads, brain, adipose tissue (E.g. found in the breast), placenta, blood vessels, skin, bone, and endometrium.

-   Health conditions where inappropriately high levels of aromatase are present in tissues.   Endometriosis, uterine fibroids, breast cancer (enhanced aromatase activity found in breast fat)and endometrial cancer.

To see what substances increase or decrease aromatase production/activity:

Enzymes affecting steroid production/activity

Enzyme 17ß-HSD converts ESTRONE (E1) ➔  ESTRADIOL (E2)

-    E2 synthesis occurs principally through oxidation of ESTRONE (E1).    A reversible reaction;

-   ESTRADIOL (E2) /ESTRONE (E1) ratio.    Before menopause is > 1; After menopause E1 is the predominant estrogen;

-   Tissue enzymes (E.g sulfatases and 17B-HSD) originating in bowel bacterial flora and the intestinal mucosa, activate estrogens locally to ESTRADIOL (E2) and ESTRONE (E1).

Stanczyk F. Estrogens used for replacement therapy in postmenopausal women. Gynecol Endocrinol. 2001;15(suppl 4):17-25.

Both ESTRADIOL (E2) and ESTRONE (E1) can be metabolized to the biologically weaker ESTRIOL (E3) 

DIM Effect on Estrogen Metabolites

Estrogens are also metabolized to a number of other estrogen metabolites - some GOOD / some BAD:

WITH estrogen-lowering dietary components (E.g. antagonists such as DIM*, quercetin, phytoestrogens), efficient aerobic estrogen metabolism results in predominantly “GOOD” estrogen metabolites.     E.g. 2-hydroxy and 2-methoxyestrogens function as antioxidants, and have the power to eliminate damaged or cancerous cells throughout the body.

-    WITHOUT estrogen-lowering dietary components, INefficient anaerobic estrogen metabolism results in predominantly “BAD” estrogen metabolites.     E.g. 16-hydroxy ESTRONE and 4-hydroxy ESTRONE,    which function as damaging oxidants that can ultimately promote cancer.

* Diindolylmethane (DIM) is a stable indole found in cruciferous vegetables

DIM - Estrogen Blocker with Anti-Cancer Benefits