Globulin that binds sex hormones – what is it?

In the body of men and women there is a glycoprotein, which is responsible for the binding and transmission of sex hormones in the circulatory system. Speaking in a language understandable to the reader, this globulin acts as a shuttle for the sex hormones of men (androgens) and women (estrogens).

This globulin is referred to in the analysis results as SHBG. In addition, the following abbreviations may be used:

• SHBG (Sex hormone-binding globulin).

• TeBG (Testosterone-estrogen-binding globulin).

• Sex globulin.

• ASG – androgen-binding globulin.

• SSSG is a sex steroid-binding globulin.

• PSSH is sex steroid-binding globulin.

• TESH stands for testosterone-estradiol-binding globulin.

This globulin, regardless of its name, is produced in the liver. The rate and amount of globulin produced is influenced by a person’s age, as well as the level of sex hormones in the blood. Estrogens contribute to an increase in its level, and androgens, on the contrary, reduce this indicator.

Normal levels of SHBG in the blood of men and women

In men, globulin that binds sex hormones is two times less than in women. An analysis for this protein is carried out when a decrease in the level of androgens is found in a man. Women are advised to donate blood for SHBG with an increase in the amount of estrogen in the blood.

SHBG is determined by ELISA (enzymatic immunoassay), or by ICLA (chemiluminescent immunoassay). The latest study is more recent.

The level of sex hormone-binding globulin can vary depending on the following factors:

• The gender of a person.

• The age of the person.

• The amount of sex hormones in the body.

• The presence or absence of obesity.

• Presence or absence of liver disease.

• Acceptance of hormonal drugs.

• The quality of functioning of the adrenal and thyroid glands, which also produce hormones.

When interpreting the results of the analyzes, it is required to focus on the norms given in the table.

Blood SHBG level:

In childhood, the level of hormone-carrying globulin is increased compared to adults. As a person ages, the amount of this globulin begins to grow again, which falls on the period of extinction of human sexual functions. In men, a similar situation is observed against the background of age-related androgen deficiency, in which the level of free testosterone begins to fall.

Testosterone and SHBG

Testosterone is called the main male hormone. It is produced in the testes and testicles from Ledwig cells. In women, testosterone is also present in the body, but normally, it is very small. It is produced by the adrenal glands and ovaries. Also, testosterone in humans in a small amount appears as a result of metabolic processes between corticosteroids.

Testosterone is responsible for the formation of sexual characteristics in adult men, for the formation of the genital organs in the male fetus, for the normal orientation of a person. After the onset of puberty, this main hormone of the male body ensures its sexual functions, makes it possible to continue its race.

The following transformations can occur with testosterone in the blood:

• Approximately 2% of free testosterone is always present in human blood. It binds to receptors that are found on target tissue cells. Then enzymes act on it, and testosterone is transformed into dihydrotestosterone, which has a pronounced effect on the body.

• A small amount of testosterone binds to other blood proteins, such as albumin or globulin, which is responsible for attaching to cortisol. If the level of SHBG falls for any reason, then it is these compounds that ensure the transport of the hormone to the desired cells. It should be noted that the relationship of testosterone with albumin and other proteins (except for SHBG) is not strong.

• The main transport function of testosterone to target cells is performed by globulin, which binds sex hormones. Such a connection is stable and most reliable.

All testosterone that is present in human blood (unbound, bound to SHBG or other globulins and proteins) is total testosterone. After the testosterone molecule is attached to the carrier substance, it loses its activity, but is not destroyed. Free testosterone and bound testosterone in the blood balance each other, since both forms contain biologically active substances. In general, bound and free testosterone are referred to as bioavailable testosterone.

Since testosterone performs significant functions in the human body, SHBG is also considered a very important globulin. It is directly involved in the transport function of androgens, providing a normal human hormonal background.

SHBG and the health of the male reproductive system

SHBG is responsible for the balance of androgens in the male body. If necessary, it takes on excess free testosterone. The level of sex hormone-binding globulin affects the level of available testosterone in the blood.

SHBG regulates in the male body not only the level of testosterone, but also estrogen. They are produced in men very little, while about 20% of the total amount of estrogens is carried by SHBG. The situation with hormones is somewhat different in men over the age of 60. They have more female sex hormones in their blood, but SHBG does not take them on itself, since it is mainly involved in the transport of testosterone.

SHBG defines men’s health. Its level is influenced by the age of a man, since at different periods of life, the amount of sex hormones in the blood varies.

In addition to SHBG and testosterone, another indicator affects the sexual health of men – the free androgen index (ISA). It characterizes the level of a biologically active substance or free testosterone in the blood. To determine its indicator, you must use the following formula: total testosterone in nmol / l must be divided by sex hormone-binding globulin in nmol / l and multiplied by 100% (T_general : SHBG x 100% = ISA).

Normally, the level of ISA in healthy men should be 50%. If this value is below this limit, then hypogonadism or chronic inflammatory processes in the prostate should be suspected. The level of ISA also decreases in men in old age, which is associated with reduced activity of sexual functions.

The level of SHBG is of great importance in the detection of various diseases of the reproductive system. This analysis is prescribed as an auxiliary study in determining the level of total testosterone in the blood, when calculating the level of ISA.

Reasons for increasing and decreasing SHBG

If the level of globulin that carries sex hormones decreases or increases, then this is reflected in the state of the hormonal background as a whole. Such a situation cannot go unnoticed.

If SHBG is elevated, it will promote the growth of prostate tissue, which entails the risk of the formation of cancerous tumors.

Diseases that can lead to an increase in SHBG levels:

• Hepatitis.

• Hyperthyroidism.

• HIV.

In women, during gestation, the level of this hormone can also be increased, but this is a variant of the norm.

Pathologies in which PSPG can be lowered:

• Nephrotic syndrome, in which proteins are excreted by the kidneys in large volumes.

• Collagen diseases.

• Itsenko-Cushing’s disease.

• High levels of male sex hormones in the female body.

• Polycystic ovary syndrome.

• Hypothyroidism.

• Benign neoplasms of the pituitary gland.

• Diabetes mellitus of the second type.

The risk of developing type XNUMX diabetes increases with a fall in PSPG levels. An additional factor contributing to the manifestation of the disease is the pathology of the pancreas. It does not matter whether such violations occur in the body of a woman or in the body of a man.

Symptoms of high and low PSBG levels

If a person in the body decreases or increases the level of PSPG, then this will be characterized by the following symptoms:

• Disorders in the sexual sphere.

• Increased fatigue and weakness.

• Depressive moods, excessive irritability and aggressiveness.

• Inattention.

• Hot flashes.

• Increased bone fragility.

• If you have a diagnosis of diabetes, the body will be less able to absorb insulin.

• Sudden weight loss or obesity.

• Deterioration of the body’s natural defenses.

• Hair loss, oily dandruff and acne.

• Violation of the menstrual cycle.

• The growth of the mammary glands in a man.

If a man finds such symptoms in himself, then he should consult a doctor. The doctor will prescribe tests that will assess the hormonal background of the patient. An andrologist should be engaged in the diagnosis of “male diseases”, if there is no opportunity to contact such a narrow specialist, then an endocrinologist or urologist should be visited. Women need to go to see a gynecologist.

An analysis to determine the level of SHBG is prescribed to the following categories of citizens:

• People who cannot conceive a child.

• Men suffering from impotence at a young age.

• Women suffering from menstrual irregularities.

• Women who have male-pattern body hair growth.

• Men aged, in the period of extinction of sexual functions.

Special preparation for blood donation to determine the level of SHBG is not required. Blood is taken in the morning. The maximum concentration of the hormone in the blood is observed between 8-11 am. It is not recommended to smoke, worry, overwork before the procedure. Donate blood on an empty stomach.

Video: about SHBG for men: