What are estrogen
Estrogens are a group of sex hormones typical of the female body. They are secreted mainly by the ovary in response to the stimulation of a pituitary hormone called LH or luteinizing . A small amount of estrogen is also produced by the adrenal glands and by the conversion of other hormones; in modest quantities they are also present in the male organism.
They belong to the category of steroid hormones, a group of natural and artificial substances characterized by a structure with four condensed hydrocarbon rings.
The best known and most important estrogen is estradiol and, as shown in the figure, is processed by the ovaries starting from testosterone during the fertile age of the woman; in pregnancy , on the other hand, there are high concentrations of another estrogen, called estriol , produced in high quantities by the placenta ; in menopause estrone prevails , which derives for the most part from the transformation of androstenedione in the adipose tissue.
|· In addition to estrogen, the ovary produces powerful androgens (male sex hormones) responsible for hair growth and also important for libido.
· The tissues most sensitive to estrogenic activity are the ovary, uterus and breast. However, as we will see more in the next section, estrogen also acts on other structures by regulating numerous bodily functions.
Functions in women
Both natural and synthetic estrogens perform very important physiological functions.
First of all, they regulate sexual maturation by intervening in the development of the genital system .
Their massive secretion in puberty induces the closure of the conjugation cartilages of the long bones , effectively ending the phase of statural growth .
Estrogen stimulates breast stromal development and the maintenance of secondary female characteristics (breast growth, hair distribution, voice, height , bone, fat distribution).
They allow fertilization and pregnancy, intervening in the regulation of the menstrual cycle
They regulate the distribution of body fat , favoring its deposit in the hips, buttocks, thighs and abdomen below the navel .
They maintain bone trophism and therefore have a protective action against osteoporosis
They stimulate the synthesis of triglycerides and the increase of high density lipoproteins (HDL or good cholesterol ) protecting the vessel walls from arteriosclerotic damage. Since women have much more estrogen than men until menopause, the risk of developing cardiovascular disease is considerably lower.
They stimulate lipolysis in muscle and adipose tissue. For this reason, estrogens improve the performance of endurance sports by saving muscle glycogen at the expense of fatty acids.
They regulate many brain functions including attention and memory.
They stimulate the hepatic synthesis of numerous enzymes and proteins ( SHBG , angiotensinogen).
Some natural foods such as soy contain substances that mimic the effects of estrogen.
SOME ESTROGENS USED IN THERAPY:
|Estradiol||In menstrual disorders due to endocrine imbalance, in symptoms of estrogen deficiency, resulting from physiological or surgical menopause|
|Estriol||in menstrual disorders due to endocrine imbalance, in the treatment of menopause disorders|
|Ethinylestradiol||in menstrual disorders due to endocrine imbalance, in the treatment of menopause disorders|
|Promestriene||in urogenital atrophy, in estrogen deficiency vaginitis .|
|Ethinylestradiol + cyproterone||in androgenic acne and female androgenetic alopecia|
|Ethinylestradiol-progestogen combinations||prevention of conception|
|Estradiol + progestin combinations||symptoms of estrogen deficiency|
Despite all these beneficial properties, an excess of estrogen is dangerous both from an aesthetic and health point of view. If on the one hand these hormones favor the accumulation of adipose tissue and the appearance of water retention , on the other hand they expose the woman to a high risk of developing some forms of cancer such as breast cancer, insulin resistance , infertility and ovarian disease.
The most effective way to keep estrogen levels normal is to keep your body weight under control . In the female body, about two thirds of estrogen production takes place in adipose tissue thanks to an enzyme that converts the androgens produced by the adrenal glands into estrogen.
Functions in Man
In humans, the amount of estrogen secreted by the testis is particularly modest, although biologically important. However, as we age, especially in the case of reduced physical activity and obesity, a natural decline in testosterone production is associated with an increase in its conversion into estrogen.
This phenomenon is linked to unpleasant side effects such as gynecomastia , decreased sexual desire, erection problems and decreased fertility.