Steroid hormones
Steroid hormones can be grouped into 2 classes: corticosteroids (typically made in the adrenal cortex) and sex steroids (typically made in the gonads or placenta).
Corticosteroids are subdivided in to the glucocorticoids (e.g. cortisol (=hydrocortisone) and cortisone; essential for metabolism of carbohydrates, proteins, and fats; anti-inflammatory activity) and the mineralocorticoids (principally aldosterone; maintenance of electrolyte and fluid balance). Corticosteroids are agonists of nuclear hormone receptors: glucocorticoids act via the glucocorticoid receptor and mineralocorticoids act via the mineralocorticoid receptor. These belong to a receptor family (3-ketosteroid receptors) which also includes the androgen receptor and progesterone receptor.
Sex steroids (or gonadal steroids) are those hormones which act via the androgen, estrogen or progesterone receptors (link to estrogen receptor family). Natural sex steroids are synthesized by the gonads, adrenal glands, or are converted from other sex steroids in the liver or adipose tissue.
Endocrine organ | Secreted hormone(s) | Effect(s) |
---|---|---|
Adrenal glands- cortex | glucocorticoids- zona fasciculata and zona reticularis cells | stimulates gluconeogenesis; stimulates fat breakdown in adipose tissue; inhibits protein synthesis and glucose uptake in muscle and adipose tissue; immunosuppressive; anti-inflammatory |
mineralocorticoids- zona glomerulosa cells | stimulates active sodium reabsorption and passive water reabsorption in kidneys (increasing blood volume and pressure); stimulates renal potassium and H+ excretion | |
androgens (secondary site of synthesis): DHEA and testosterone- zona fasciculata and zona reticularis cells | masculising effects in females; in males, effects are insignificant compared to those elicited by testicular androgens | |
Adipose tissue | estrogens (mainly estrone)- adipocytes | |
Reproductive organs- ovarian follicle and corpus luteum | progesterone- granulosa cells, theca cells | supports pregnancy |
androstendione- theca cells | metabolic precursor of both testosterone and estrone | |
estrogens (mainly estradiol)- granulosa cells | promotes development of secondary female sex characteristics; stimulates endometrial growth | |
Testes | androgens, principally testosterone | virilizing action (prenatal and pubertal); anabolic action; spermatogenesis |
Corticosteroids in the clinic
Cortisol and synthetic corticosteroids are used widely as anti-inflammatory agents. Corticosteroids are available in different forms, including tablets, injectable forms, inhalation forms and topical lotions and creams. They are used to treat a huge variety of inflammatory conditions including asthma, allergic rhinitis and hay fever, urticaria, atopic eczema, chronic obstructive pulmonary disease (COPD), painful and inflamed joints, muscles and tendons, lupus, inflammatory bowel disease (IBD; including Crohn's disease and ulcerative colitis) and multiple sclerosis (MS). In Addison's patients corticosteroids are used as hormone replacement therapy.
Corticosteroids are prescribed at the lowest effective dose for the shortest possible time due to the long-term side-effects (e.g. weight gain, acne, thinning of the skin, osteoporosis, hypertension and diabetes).
Example corticosteroids
Betamethasone- for short-term topical treatment of local inflammation (eyes, skin), inflammatory and allergic disorders and asthma
Beclometasone- for similar indications as betamethasone
Clobetasone and clobetasol propionate- used topically to treat eczema, psoriasis and other forms of dermatitis. Clobetasone used in eye drops to treat dry eyes in Sjögren's Syndrome.
Fluticasone- for asthma
Hydrocortisone (the approved name for cortisol)- used widely for mild inflammatory skin disorders such as eczemas.
Methylprednisolone- suppression of inflammatory and allergic disorders, treatment of local inflammation of joints and soft tissues, treatment of cerebral oedema associated with malignancy, treatment of graft rejection reactions,
Prednisolone- is widely used to suppress inflammatory and allergic reactions in a range of conditions including COPD (where increased breathlessness is interfering with daily activities), croup, acute asthma, idiopathic thrombocytopenic purpura, eczematous inflammation in otitis externa, ulcerative colitis, Crohn’s disease, rheumatoid arthritis, polymyalgia rheumatica and giant cell (temporal) arteritis.
Triamcinolone- intra-articular and peri-articular injection to treat local inflammation of joints and soft tissues
Aldosterone antagonists
Spironolactone is a potassium-sparing diuretic, which works by antagonising the effects of aldosterone. Used adjunctively to treat moderate to severe heart failure and resistant hypertension. Additional indicated conditions include Nephrotic syndrome, oedema in congestive heart failure, ascites in cirrhosis of the liver and malignant ascites.
Eplerenone works by the same mechanism as spironolactone. This drug is used adjunctively in heart failure patients with low left ventricular ejection fraction.
More information about these drug is contained in the Diuretics section of Cardiovascular system drugs.
Sex steroids in the clinic
The primary clinical use of testosterone is as hormone replacement therapy for males who produce sub-normal levels or no testosterone, which can cause hypogonadism. Testosterone production declines with age (the andropause). Testim®, Tostran® and Testogel® are testosterone medications used to treat hypogonadism due to testosterone deficiency.
Synthetic androgens are the anabolic steroids, often abused by athletes and other sportspeople to increase muscle strength and muscle mass, and possibly endurance. Nandrolone has been used clinically, but has been discontinued in the United States. It is approved in the UK to treat osteoporosis in postmenopausal women, but its use is not recommended.
Antiandrogens (or androgen receptor antagonists) are used to treat a variety of androgen-dependent conditions. In men they are most frequently used to treat prostate cancer, and also benign prostatic hyperplasia, and severe male sexual disorders (e.g. hypersexuality). In women they are used to reduce male hormone levels which cause hyperandrogenism and can be prescribed to treat acne, amenorrhea, seborrhea, hirsutism, androgenic alopecia, hidradenitis suppurativa.
Flutamide, nilutamide (not approved in the UK), bicalutamide and enzalutamide are non-steroidal antiandrogens. Combined androgen blockade and castration (orchidectomy) is used as a safe and effective prostate cancer therapy. Cyproterone acetate and abiraterone acetate are additional androgen receptor antagonists available to the prescriber. Abiraterone is primarily used in patients with metastatic castration-resistant prostate cancer.
5α-reductase inhibitors such as finasteride and dutasteride prevent the conversion of testosterone to dihydrotestosterone (DHT), so are indirectly antiandrogenic. 5α-reductase inhibitors are most often used to treat benign prostatic hyperplasia. The alpha-adrenoceotor antagonist tamsulosin can be used alongside 5α-reductase inhibitors to provide symptomatic relief in benign prostatic hyperplasia patients, as it acts to decrease urinary outflow resistance.
Progesterone receptor modulators
In the UK mifepristone is licensed to induce cervical ripening in preparation for mechanical termination of pregnancy procedures (up to 84 days gestation), to induce chemical termination of pregnancy (up to 49 days gestation; typically used with the prostaglandin E analogue misoprostol) or to induce labour in cases of fetal death in utero. Ulipristal acetate is used as emergency contraception (contained in the ellaOne morning after pill, which must be taken within 120 hours of sex) and for pre-operative and intermittent treatment of moderate to severe symptoms of uterine fibroids.
Synthetic progestogens (progestins) and estrogens are used in methods of hormonal contraception and to treat various reproductive and gynaecological conditions.
Progestins used in the clinic include:
Progesterone- used in assisted reproductive technology (ART) cycles to supplement the luteal phase and to treat infertility due to inadequate luteal phase, to provide progestogenic opposition of oestrogen HRT, and to treat premenstrual syndrome, dysfunctional menstrual bleeding and post-natal depression.
Medroxyprogesterone acetate is a long-acting progestin used in 'depo' contraceptives such as Depo-Provera®, given by injection every 12 weeks to maintain full protection. Such preparations can also be used to treat dysfunctional menstrual bleeding, secondary amenorrhoea, mild to moderate endometriosis, and to provide progestogenic opposition of oestrogen HRT. Medroxyprogesterone acetate is also used in treatment of endometrial, breast and renal cancers.
Etonogestrel- used in hormonal contraceptive implants (e.g. Nexplanon®) which are inserted subdermally into the lower surface of the upper arm and provide contraception for up to 3 years.
Norethisterone- a long-acting (8 weeks duration) progestin given by injection. It is used to stop bleeding in women with menorrhagia and dysfunctional menstrual bleeding, to treat endometriosis, dysmenorrhoea and premenstrual syndrome. Norethisterone can also be used to postpone menstruation and can be used in the treatment of breast cancer.
Desogestrel- used in hormonal contraceptives.
Megestrol acetate- used in the treatment of breast cancer.
Levonorgestrel- used in hormonal contraceptives, including as emergency contraception (e.g. Levonelle; one 1.5 mg dose taken as soon as possible after coitus, preferably within 12 hours but no later than after 72 hours). Levonorgestrel is the progestin used in progestogen-only intra-uterine devices such as Mirena®, Jaydess® and Levosert®. These IUDs are a good option for women with excessively heavy menses.
Synthetic estrogens
Synthetic estrogens are used clinically as a component of a large number of combined oral contraceptives, in estrogen replacement therapy for postmenopausal women, and hormone replacement therapy for trans women.
Ethinylestradiol is the most commonly used estrogenic compound contained in combined oral contraceptives. Estradiol (and its valerate salt) are also used in these birth control pills, as is mestranol (inactive prodrug of ethinylestradiol).