Estrogens: types, functions and effects on the body

This group of sex hormones has various effects on the bodies of men and women.

The endocrine system consists of the set of organs and tissues of the body, which secrete a type of substances - hormones. Here we will learn about one type of female sex hormones, estrogens, as well as the different types of estrogens.as well as the different types of estrogens that exist.

Hormones are released into the bloodstream and regulate some of the body's functions. The main female sex hormones, naturally secreted by the body, are estradiol, estrone and estriol.

Characteristics of estrogens

Estrogens are steroid sex hormones, mainly female, although they are also secreted in men (to a lesser extent). (to a lesser extent). They are responsible for the development of female secondary sexual characteristics, such as breast growth.

The different types of estrogens are produced by the ovaries, the placenta (during pregnancy) and, to a lesser extent, by the adrenal glands. The hypothalamic-pituitary axis plays an essential role in their secretion. Specifically, in the ovaries are produced in response to signals from the brain and other organs.in both vertebrates and invertebrates.

Chemistry of these hormones

At the chemical level, the estrogen molecule is based on the phenanthrene structure. is based on the phenanthrene structure (chemical structure type). (type of chemical structure).

As for their biosynthesis, this involves the aromatization of testosterone by the enzyme aromatase. Aromatase is present in many tissues, including adipose and brain.

Types of estrogens

According to their type of synthesis or origin, we can speak of three types of estrogens:

1. Natural estrogens

These are those secreted by the body itself. The most important ones: estradiol, estrone and estriol..

2. Semi-synthetic estrogens

These are steroids derived from estradiol. There are three different ones:

• Ethinylestradiolof great estrogenic potency, it is very active orally.
• Mestranolis generally used together with progestogens.
• Quinestrol.

3. Synthetic non-steroidal estrogens

They are not steroids, and are orally active. They acquire a certain chemical similarity to steroids and are able to activate estrogenic receptors. are capable of activating potent estrogenic receptors, so they are very useful in theso they are of great therapeutic utility. The main ones are three:

• Dienestrolis or was used to treat menopausal symptoms.
• Diethylethylbestrol or ethylbestrol: it is the best known and classic.
• ChlorotrianiseneIn the body, it is transformed into a long-acting active estrogen (proestrogen).

Mechanism of action and functions

In humans (and all vertebrates), the three main natural estrogens are estrone, estradiol and estriol. Of these three, estradiol is the most potent, as it has the highest affinity for estrogen receptors.

These three main estrogens are secreted mainly by the developing follicles in the ovaries, the corpus luteum, the corpus luteum and the the ovaries, the corpus luteum of the placenta, adrenal cortex, brain, testes, liver and adipose tissue..

But how do estrogens operate in the body? The mechanism of action of estrogens has to do with the nuclear receptors of the cells. Their function is to regulate gene expression and promote the synthesis of specific mRNAs (messenger RNAs). (messenger RNA).

In addition, estrogens induce the synthesis of receptors for progesterone production in cells of different tissues.

Effects on men and women

The effects of estrogens are also noticeable in prenatal and postnatal prenatal and postnatal development in both males and females.. Thus, the specific relationship between estrogen and androgens (male sex hormones) is required for the proper differentiation and formation of the reproductive organs. If this relationship is disturbed, the reproductive organs may develop incompletely or abnormally.

In women, the function of these hormones is to prepare the uterus to accept the fertilized eggas well as to help with pregnancy and lactation. One author, Hileman (1994), proposed that estrogens decrease the risk of heart attacks and osteoporosis, but increase the risk of breast and uterine cancer.

In men, estrogens regulate spermatogenesis (sperm synthesis) in the male reproductive system. However, if estrogen concentration in men is high, it may inhibit sperm production.

Pharmacological actions

At the pharmacological level, estrogens have various actions. These actions can be specific (when they act on specific sites of action, for example on the breasts, genitals, vagina, tubes, etc.) or non-specific (for example in relation to prolactin, thyroid, adrenal, etc.).

Let's see some examples of non-specific pharmacological actions of estrogens:

1. prolactin

Estrogens increase the synthesis and release of prolactin, a hormone that stimulates the production of estrogens.a hormone that stimulates milk secretion, especially when a woman is pregnant.

Thyroid

The thyroid gland is an endocrine gland that regulates the body's metabolism and regulates regulates the body's metabolism and the body's sensitivity to other hormones.. In this case, estrogens at low doses increase its activity (hyperthyroidism), and at high doses, they inhibit it (hypothyroidism).

3. Protein anabolism

The presence of estrogens increases the protein anabolism, i.e, the synthesis of proteins from amino acids..

4. Coagulation

Some of the different types of estrogens also promote Blood coagulation. Coagulation involves the blood turning into a gel to form a clot.

Adverse effects

Depending on whether there is an excess or a low concentration of estrogens, we may encounter different adverse effects on the body:

1. by high concentration 2.

Some of the adverse effects of high estrogen concentration are an increase in cervical mucus (cervical discharge in women), as well as an increase in the size of the uterus. Excess estrogen also produces hypermenorrhea. (very heavy menstrual bleeding at regular intervals) and dysmenorrhea (pain before menstruation).

A possible cause of exposure to high concentrations of estrogens are drug treatments used for hormone replacement, menstrual cycle regulation or contraceptive methods.

2. Due to a decrease in concentration

There are mainly two adverse effects: metrorrhagia (unscheduled vaginal bleeding) and amenorrhea (absence of menstruation).

Other treatments in animals

Estrogens, in addition to contraceptive treatments in humans, are also used in hormonal therapies with are also used in hormonal therapies with animals (livestock for food production, and domestic animals).

Some of their therapeutic purposes are: the use of estradiol to induce and synchronize the estrus period in cows, or estriol for the treatment of urinary incontinence in bitches.

Bibliographic references:

• Hileman, B. (1994). Environmental Estrogens Linked to Reproductive Abnormalities, Cancer. Chemical & Engineering News, 72(5), 19-23.
• Ramirez-Sanchez, I., Martinez-Austria, P., Quiroz-Alfaro, M. and Bandala, E. (2015). Health and environmental effects of estrogens as emerging contaminants. Tecnología y Ciencias del Agua, 6(5), 31-42.