Official website of the Johns Hopkins Antibiotic (ABX), HIV, Diabetes, and Psychiatry Guides, powered by Unbound Medicine. Johns Hopkins Guide App for iOS, iPhone, iPad, and Android included. Explore these free sample topics:
-- The first section of this topic is shown below --
- Testosterone (T) and estradiol (E2) have important metabolic actions which are gender-specific (sex-dimorphic).
- Most T and E2 circulate bound to sex hormone-binding globulin (SHBG), a glycoprotein that regulates the amount of sex steroids available for biological action.
- Of total T, 54% weakly bound to albumin and other proteins, 44% bound to SHBG, 2% unbound (free T).
- In reproductive age women, one third of T is secreted by the ovary, whereas two thirds arise from the peripheral conversion of androstenedione to T.
- Androstenedione is directly produced by the ovary but also from peripheral conversion of adrenal dehydroepiandrosterone sulfate (DHEA-S).
- Male Hypogonadism (for example, with androgen deprivation therapy for prostate cancer) is linked to the metabolic syndrome, type 2 diabetes and an increased risk for cardiovascular disease.
- Hyperandrogenism in women (for example, with polycystic ovarian syndrome) is linked to the metabolic syndrome, type 2 diabetes and cardiovascular disease. High T in postmenopausal women is also linked to an increased risk of type 2 diabetes.
- High endogenous E2 is associated with an increased risk for type 2 diabetes in males and postmenopausal women.
- Low SHBG is a risk factor for type 2 diabetes in both males and females.
- A recent study suggested that women under the age of 45 years who have type 2 diabetes have three times the risk of early menopause compared to women without diabetes.
- Low total T may be associated with more advanced atherosclerotic disease markers in middle-aged men with type 2 diabetes.