ENDOCRINE hormones are chemical "messengers" used for intercellular communication, released by glands directly into the bloodstream. There are 3 types of endocrine hormones, namely, amines, polypeptides, steroid hormones. For basic information on hormones:
Hormones 101 -"Feel Good, Look Good"
STEROID hormones (subset of endocrine hormones) are fat-soluble hormones produced from cholesterol. They include: glucocorticoids, mineralocorticoids, sex steroid hormones and vitamin D sterols
SEX STEROID HORMONES (subset of steroid hormones) produce sex differences or support reproduction. These are the:
- Androgens - include: DHEA, ANDROSTENEDIONE, TESTOSTERONE, DHT
- Estrogens - include: estradiol, ESTRONE, ESTRIOL;
- progestagens. Include: PROGESTERONE, PREGNENOLONE
PROGESTERONE - "Precursor to Androgens, Estrogens and COrticoids"
All steroid hormones are produced/secreted by the ovaries (ovarian follicle /Corpus luteum), testes, prostate, and adrenal cortex. In addition, further conversions, break-downs and secretions occur inthe liver, extragonadal sites (E.g. adipose tissue, skin fibroblasts, bone, placenta) and in other target tissues.
Production requires certain enzymes
For more information, on these required enzymes, see:
Enzymes affecting Steroid Production /Activity
Steroid sex hormones are largely ignored until we hit puberty. But then, as these hormones "kick in", your body is no longer your own . . .
- Physical changes. Pimples, pubic hair,girls' breasts swell and hips become rounder, boys' facial hair begins to grow and their voices become deeper
- Weight Maintenance becomes an issue. Sex steroids are involved in adipogenesis (fat formation)
- Emotions run high. Angst, anger, confusion, depression, strong sexual urges.
- PMS. At certain times of the month you have irrational feelings. E.g. feel weepy, have cravings, snap at people.
- Pregnancy. Cravings, breast tenderness, weight gain, feeling tired, heightened sexual feelings, depression, an acute sense of smell, nausea, gray hair, straight hair gone curly, curly hair gone straight.
- Cardiovascular disease;
- Neurodegenerative disease
- Cancer formation
- Bone formation
Most sex steroid hormones are bound to carrier proteins to make them water-soluble in the blood. Only a small fraction circulates "free"/ unbound (considered to be biologically active).
- Bioavailability of ESTRADIOL or TESTOSTERONE is determined by level of Sex hormone binding globulin (SHBG);
- Bioavailability of PROGESTERONE (also CORTISOL and corticosteroidS) is determined by level of Corticosteroid-binding protein (CBG)
Drinking alcohol reduces availability of some sex steroid hormones:
Alcohol consumption affects serum levels of sex steroid hormones