• Clinical science

Estrogen and associated diseases

Abstract

Estrogen is a female sex hormone that is produced in the ovaries and, to a lesser degree, in the adrenal glands and adipose tissues. It is essential for the development of primary and secondary sex characteristics, as well as function of the reproductive organs. Estrogen also plays a role in several other processes, including bone metabolism and liver function. While ovarian insufficiency, aromatase deficiency, and hyperprolactinemia result in pathologically low estrogen levels, a decrease in estrogen is a normal feature of menopause. Possible symptoms of estrogen deficiency include menopausal symptoms, vaginal and endometrial atrophy, and osteoporosis. Increased estrogen levels may also have adverse effects, including gynecomastia, thrombosis, and an increased risk of breast and endometrial cancer.

Biochemistry

  • Estrogen synthesis primarily takes place in the ovarian granulosa cells
    • LH stimulates androgen synthesis in ovarian theca cells.
    • FSH stimulates conversion of androgens to estrogens.
    • Conversion of androgens to estrogens is catalyzed by the aromatase enzyme.
  • Estrogen is also produced in other aromatase-containing tissues:
  • Types of estrogen: estradiol, estrone, estriol

Obesity increases the risk for postmenopausal breast cancer. It is hypothesized that this is due to estrogen production in adipose tissue!

References:[1][1][2][3][4][5]

Effects

Estrogen is a steroid hormone that promotes female sexual development and stimulates the growth and maturation of primary and secondary sex characteristics.

Genitalia/sex characteristics

Extragenital tissue

References:[1][1][6][7][8][9][10][11][12]

Adverse effects

Adverse effects of estrogen can arise from high levels secondary to increased endogenous production or medication. :

Although estrogen is a risk factor for the development of some types of cancer, it reduces the risk of colon cancer!

High estrogen levels increase the risk of thrombosis!

References:[1][1][13][13][14][3][15][12][16][17]

Estrogen deficiency

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last updated 11/19/2018
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