Concentration of sex steroids in adipose tissue after menopause.
نویسندگان
چکیده
Adipose tissue is a site of uptake, storage, action, and metabolism of sex steroids. After menopause aromatization of androgens to estrogens in adipose tissue is one of the most important sources of estrogen in the circulation and for peripheral tissues. The aim of this study was to estimate local sex steroid concentrations in breast and abdominal subcutaneous (s.c.) adipose tissue, to compare them with plasma concentrations and to investigate possible correlations with body mass index (BMI). The patients were postmenopausal women undergoing surgery for non-oncological reasons (Group A; n = 35) and breast cancer patients (group B; n = 19). The concentrations of estrone, 17 beta-estradiol, estrone sulfate, 17 beta-estradiol sulfate, androstenedione, androstenediol (androst-5-ene-3 beta, 17 beta-diol), testosterone and dehydroepiandrosterone were measured. The method was based on frozen tissue homogenization, extraction with ethanol: acetone, delipidation, extraction of estrogens with ether, and of androgens with iso-octane in toluene, followed by RIA. The mean levels of steroids were higher in fat than in plasma, apart from testosterone. Levels of sulfates of estrogens and androstenediol were higher in breast than abdominal adipose tissue, and levels of estradiol lower. Positive correlations were found between BMI and tissue and plasma concentration of both estrone and androstenedione.
منابع مشابه
Leptin in Breast Cancer: Its Relationship with Insulin, Estrogens and Oxidative Stress
Breast cancer is the most common cancer in women. Several risk factors such as age, family history of breast cancer, marital status, early menarche and late menopause are related to breast cancer. Obesity is also a main health problem associated with breast cancer incidence and subsequent mortality. Association between obesity and expansion of breast cancer may be due to excessive sex steroid h...
متن کاملConditional deletion of hypothalamic Y2 receptors reverts gonadectomy-induced bone loss in adult mice.
Reduction in levels of sex hormones at menopause in women is associated with two common, major outcomes, the accumulation of white adipose tissue, and the progressive loss of bone because of excess osteoclastic bone resorption exceeding osteoblastic bone formation. Current antiresorptive therapies can reduce osteoclastic activity but have only limited capacity to stimulate osteoblastic bone for...
متن کاملTestosterone and secondary hypertension: new pieces to the puzzle.
The absence of estrogen, in males or after menopause in women, is independently associated with increased cardiovascular risk. A number of factors have been implicated as the underlying cause, including effects at the cell-organ level (eg, inflammatory activation, increased oxidative stress, and increased vasoconstriction), as well as changes in cardiovascular physiology (eg, sympathetic activa...
متن کاملSteroid sulfatase activity in subcutaneous and visceral adipose tissue: a comparison between pre- and postmenopausal women.
OBJECTIVE Adipose tissue is an important extragonadal site for steroid hormone biosynthesis. After menopause, estrogens are synthesized exclusively in peripheral tissues from circulating steroid precursors, of which the most abundant is dehydroepiandrosterone sulfate (DHEAS). Our aim was to study activity of steroid sulfatase, an enzyme hydrolyzing DHEAS, and expression of steroid-converting en...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Steroids
دوره 63 5-6 شماره
صفحات -
تاریخ انتشار 1998