Androgens are hormones that are mainly responsible for the generation and development of male sexual characteristics. However, unlike popular belief, androgens are present in both men and women. The action of androgens start right in the fetal stage where they play a major role in the development of male sexual organs. Hormonal imbalances resulting from higher or lower levels of androgen lead to Hirsutism in women and infertility and lack of libido in men.
What are androgens?
Androgens are steroid sex hormones. In conjunction with androgen receptors, they play a vital role in the development of male sexual characteristics right from the fetal stage. They are instrumental in the transformation of sexual organs during puberty.
Types of androgens
There are various types of androgens in both men and women. In men, they are produced to a large extent in the testes and in smaller quantities in the adrenal cortex of adrenal glands. In the testes, they are produced in the Leydig cells in the form of testosterone (testosterone is a form of androgen). Types of androgens include:
Dihydrotestosterone (DHT)
This is a metabolic byproduct of testosterone and enzymes. This hormone is vital for sexual differentiation in the fetal stages. This hormone is responsible for the formation of male sexual organs during fetal stages, and sexual maturation during puberty. They are also responsible for the maintenance of prostate glands.
Imbalances in the levels of DHT is known to cause male pattern baldness, enlargement of prostate glands, and adult acne when the levels of DHT are on the higher side. When DHT levels reduce in men, it leads to improper genital development.
Dehydroepiandrosterone (DHEA)
This is an adrenal androgen. It is produced in the adrenal cortex. DHEA is a steroid hormone that is synthesized from cholesterol and is also produced in the brain and the gonads. Though DHEA is termed as a weak androgen, it is responsible for sexual maturation, and body characteristics that show up with sexual maturation in men.
Androsterone
This is another steroid hormone and a weak androgen when compared to testosterone. Androsterone is produced as a byproduct of other androgens (testosterone & DHT) and is known to have pheromone activity. It is present in the skin, and sebaceous glands and has a musky odor and can change behavior patterns when it is smelled.
Androstenedione
This is a steroid hormone that changes into testosterone with the action of enzymes. It is produced in the testes and adrenal cortex.
Androstenediol
This is yet another weak androgen and a byproduct of DHEA. It assists in the production of testosterone. This hormone is used as a medication for enhancing growth, sexual arousal, and increase the production of testosterone.
Functions of Androgens
Androgens are important hormones in both men and women. In men, they help in formation, and maturity of male sexual organs. Its action is both vital in the fetal and puberty stages. It is vital for the production of sperms where it works along with luteinizing hormone and the follicle-stimulating hormone. They act on the Sertoli cells of the testes and improve sperm production.
Other functions of androgens include:
- Formation of muscle mass.
- Restricting fat formation in men
- Causing behavioral patterns/changes in men when it circulates in the brain.
Androgen Imbalance
Hormonal imbalances and other actions tend to create androgen excess/deficit. In men, sexual maturation during puberty is characterized by an excess level of adrenal androgens. This is called adrenarche. It leads to:
- Presence of pubic and chest hair
- Thickening of vocal cords
- Increased muscle and bone growth
- Increased activity of sweat glands
In women, hormonal disorders result due to excess androgens. This causes PCOS and other menstrual disorders. In men, androgens are associated with male pattern baldness, aggressive behavior, and sexual drive.
Androgen Deficiency
Reduced levels of androgens in men is called androgen deficiency. Also known as hypogonadism, this condition is characterized by a reduction in the level of testosterone and manifests in various symptoms including:
- Reduced sexual drive
- Inability to sustain erections
- Inability to achieve orgasm
- Sweating and hot flushes
- Gynecomastia
- Lethargy
- Reduced muscle mass
- Reduced bone mass
- Depression
This condition is more common among older men, who over a period of time, lose their testosterone levels. Androgen deficiency in older men is also referred to as andropause. This condition is generally treated by testosterone therapy after careful diagnosis as most symptoms are generic and can be present in other conditions like diabetes.
In people who have both other medical conditions like diabetes, testosterone replacement therapy is considered after treating other medical conditions.
Androgen Deficiency can also occur in prepubescent boys and these children require a consultation with a pediatric endocrinologist.
Causes of androgen deficiency
- Conditions of the hypothalamus in the brain can cause androgen deficiency. Presence of tumors, and other abnormalities cause imbalances and leads to reduced production of gonadotropin-releasing hormone. This causes further hormonal imbalances and leads to low testosterone.
- Conditions of the pituitary hormone like pituitary adenoma are also known to cause low testosterone levels as it interferes with the function of the anterior pituitary gland to produce luteinizing hormone and follicle-stimulating hormone thus leading to low levels of testosterone.
- Testicular problems are the most likely causes of low testosterone levels causing androgen deficiency. Genetic disorders like Klinefelter’s syndrome are known to cause androgen deficiency. Undescended testicles in children, testicular torsion, trauma to the testicles, and treatments like chemotherapy are some other causes of androgen deficiency.
Treatment for androgen deficiency is given through testosterone replacement therapy. However, this therapy does have some side effects like weight gain, breast development, androgenic alopecia, and increased aggression. Testosterone replacement therapy should be done only under the guidance and consultation of an endocrinologist.
