15-07-2014, 07:11
From Wikipedia, 'Sex hormone-binding globulin'
"the relative binding affinity of various sex steroids for SHBG is dihydrotestosterone (DHT) > testosterone > androstenediol > estradiol > estrone.[2]"
"SHBG is produced mostly by the liver"
"SHBG has both enhancing and inhibiting hormonal influences. It decreases with high levels of insulin, growth hormone, insulin-like growth factor 1 (IGF-1), androgens, prolactin and transcortin. High estrogen, and thyroxine cause it to increase."
"Conditions associated with high or low levels
SHBG levels are decreased by androgens, administration of anabolic steroids,[17] polycystic ovary syndrome, hypothyroidism, obesity, Cushing's syndrome, and acromegaly. Low SHBG levels increase the probability of Type 2 Diabetes.[18] SHBG levels increase with estrogenic states (oral contraceptives), pregnancy, hyperthyroidism, cirrhosis, anorexia nervosa, and certain drugs. Long-term calorie restriction of more than 50 percent increases SHBG, while lowering free and total testosterone and estradiol. DHEA-S, which lacks affinity for SHBG, is not affected by calorie restriction.[19] Polycystic Ovarian Syndrome is associated with insulin resistance and excess insulin lowers SHBG, which increases free testosterone levels.[20]
In the womb the human fetus has a low level of SHBG allowing increased activity of sex hormones. After birth, the SHBG level rises and remains at a high level throughout childhood. At puberty the SHBG level halves in girls and goes down to a quarter in boys.[1] he change at puberty is triggered by growth hormone, and its pulsatility differs in boys and girls. In pregnant women in the last two thirds of pregnancy the SHBG level escalates to five to ten times the usual level for a woman. A hypothesis is that this protects against the effect of hormone produced by the fetus.[1]
Obese girls are more likely to have an early menarche due to lower levels of SHBG.[1] Anorexia or a lean physique in women leads to higher SHBG levels, which in turn can lead to amenorrhea.[1]"
"the relative binding affinity of various sex steroids for SHBG is dihydrotestosterone (DHT) > testosterone > androstenediol > estradiol > estrone.[2]"
"SHBG is produced mostly by the liver"
"SHBG has both enhancing and inhibiting hormonal influences. It decreases with high levels of insulin, growth hormone, insulin-like growth factor 1 (IGF-1), androgens, prolactin and transcortin. High estrogen, and thyroxine cause it to increase."
"Conditions associated with high or low levels
SHBG levels are decreased by androgens, administration of anabolic steroids,[17] polycystic ovary syndrome, hypothyroidism, obesity, Cushing's syndrome, and acromegaly. Low SHBG levels increase the probability of Type 2 Diabetes.[18] SHBG levels increase with estrogenic states (oral contraceptives), pregnancy, hyperthyroidism, cirrhosis, anorexia nervosa, and certain drugs. Long-term calorie restriction of more than 50 percent increases SHBG, while lowering free and total testosterone and estradiol. DHEA-S, which lacks affinity for SHBG, is not affected by calorie restriction.[19] Polycystic Ovarian Syndrome is associated with insulin resistance and excess insulin lowers SHBG, which increases free testosterone levels.[20]
In the womb the human fetus has a low level of SHBG allowing increased activity of sex hormones. After birth, the SHBG level rises and remains at a high level throughout childhood. At puberty the SHBG level halves in girls and goes down to a quarter in boys.[1] he change at puberty is triggered by growth hormone, and its pulsatility differs in boys and girls. In pregnant women in the last two thirds of pregnancy the SHBG level escalates to five to ten times the usual level for a woman. A hypothesis is that this protects against the effect of hormone produced by the fetus.[1]
Obese girls are more likely to have an early menarche due to lower levels of SHBG.[1] Anorexia or a lean physique in women leads to higher SHBG levels, which in turn can lead to amenorrhea.[1]"