Loading...
  • testosterone
  • Medscape, 12/22/09 - 'The inescapable conclusion from these data is that the 50% increase in testosterone levels was trumped by the much more modest 20% reduction in estradiol levels, leading to negative skeletal effects of anastrozole therapy in aging men' - Note: I'm not sure that thought this though thoroughly. (qualitycounts.com)
  • Plus testosterone replacement increases estrogen but letrozole has the advantage of decreasing it. (qualitycounts.com)
  • tissues
  • Estradiol is responsible for the development of female secondary sexual characteristics such as the breasts, widening of the hips, and a feminine pattern of fat distribution in women and is important in the development and maintenance of female reproductive tissues such as the mammary glands, uterus, and vagina during puberty, adulthood, and pregnancy. (wikipedia.org)
  • Estradiol is produced especially within the follicles of the ovaries, but also in other tissues including the testicles, the adrenal glands, fat, liver, the breasts, and the brain. (wikipedia.org)
  • This reaction occurs in both the gonads and in certain other tissues, particularly adipose tissue, and estrone is subsequently secreted from these tissues. (wikipedia.org)
  • Estrogens are essential for development of the reproductive system in women, in whom they exert beneficial effects in a large number of tissues, including breast, bone, brain, and cardiovascular system. (biomedcentral.com)
  • Although estradiol is extensively converted into 2-hydroxyestradiol, circulating levels of 2-hydroxyestradiol and levels of 2-hydroxyestradiol in various tissues are very low. (wikipedia.org)
  • However, 2-hydroxyestradiol shows little or no tumorigenic activity in the male Syrian hamster kidney and there is evidence that 2-hydroxyestradiol may actually decrease tumorigenesis in estrogen-sensitive tissues. (wikipedia.org)
  • The main goal of our study was to assess estrogen contents of breast tumor tissues, having different estrogen receptor status, in relation to long-term follow-up of patients. (aacrjournals.org)
  • The estrogen receptor status of tissues was determined by both ligand binding and immunohistochemical assays. (aacrjournals.org)
  • A high performance liquid chromatography-based approach, jointly with gas chromatography/mass spectrometry, was used to identify and measure main estrogens, various hydroxyestrogens, and their methoxy derivatives in both normal and tumor tissues. (aacrjournals.org)
  • SHBG
  • Estrone is bound approximately 16% to sex hormone-binding globulin (SHBG) and 80% to albumin in the circulation, with the remainder (2.0 to 4.0%) circulating freely or unbound. (wikipedia.org)
  • As such, estrone is relatively poorly bound to SHBG. (wikipedia.org)
  • mammary
  • 16α-OH-estrone has been shown to be genotoxic and cause aberrant proliferation of mammary cells ( 21 , 22 ) and to covalently bind to the estrogen receptor ( 23 ). (aacrjournals.org)
  • whereas
  • For instance, 2-hydroxyestrone reportedly shows negligible uterotrophic effect in animals, whereas 4-hydroxy catechol estrogens show moderate changes in stimulating uterine weight. (wikipedia.org)
  • In females, estradiol induces breast development, widening of the hips, a feminine fat distribution (with fat deposited particularly in the breasts, hips, thighs, and buttocks), and maturation of the vagina and vulva, whereas it mediates the pubertal growth spurt (indirectly via increased growth hormone secretion) and epiphyseal closure (thereby limiting final height) in both sexes. (wikipedia.org)
  • reactive estrogen
  • 2-Hydroxyestradiol, as well as 2-hydroxyestrone and 4-hydroxyestradiol, can undergo metabolic redox cycling to generate free radicals like superoxide and reactive estrogen semiquinone/quinone intermediates. (wikipedia.org)
  • mainly
  • Estrone, as well as the other estrogens, are synthesized from cholesterol and secreted mainly from the gonads, though they can also be formed from adrenal androgens in adipose tissue. (wikipedia.org)
  • serum
  • High, Low Estradiol Levels and Mortality in Men With Systolic HF - Medscape, 5/19/09 - 'Both low and high serum levels of estradiol, compared with mid-range levels, are significantly and independently associated with increased all-cause mortality in men with chronic systolic heart failure' - Note: See my aromatization page for ways to reduce it. (qualitycounts.com)
  • Menopause
  • These changes are initiated at the time of puberty, most are enhanced during the reproductive years, and become less pronounced with declining estradiol support after menopause. (wikipedia.org)
  • Also, women past menopause experience an accelerated loss of bone mass due to a relative estrogen deficiency. (wikipedia.org)
  • primary sites on the estrogen molecule, either at the 2 carbon(C-2) position yielding 2-hydroxyestrone (2-OH) or at the After menopause, most endogenous estrogen is produced in the 16α carbon (C-16α) position yielding 16α-OH. (gotomydoctor.com)
  • Thus, estradiol is the most important estrogen in non-pregnant females who are between the menarche and menopause stages of life. (wikipedia.org)
  • dopamine
  • 2-Hydroxyestradiol is a catechol estrogen and in this regard bears some structural resemblance to the catecholamines dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline). (wikipedia.org)
  • potency
  • In relation to the fact that estrone can be metabolized into estradiol, most of its potency in vivo is actually due to conversion into estradiol. (wikipedia.org)
  • It has since been discontinued and is no longer available, having been superseded by other estrogens with greater potency and improved pharmacokinetics (namely oral bioavailability and duration). (wikipedia.org)
  • postmenopausal
  • The postmenopausal women were stratified into HT users (EPT and estrogen-only) and non-users (never HT). (biomedcentral.com)
  • Epidemiologic studies have also provided strong evidence that postmenopausal hormone therapy use, particularly the use of estrogen plus progestin (E+P), is associated with increased breast cancer risk ( 3 - 6 ). (aacrjournals.org)
  • genes
  • Reporter gene assay, Real time reverse transcription polymerase chain reaction (real time RT-PCR) and Western blot were used to assess the expression of estrogen metabolizing genes and enzymes. (jcancer.org)
  • The estrogen:ER complex binds to specific DNA sequences called a hormone response element to activate the transcription of target genes (in a study using an estrogen-dependent breast cancer cell line as model, 89 such genes were identified). (wikipedia.org)
  • vitro
  • According to one in vitro study, the relative binding affinity of estrone for the human ERα and ERβ was 4% and 3.5% of that estradiol, respectively, and the relative transactivational capacity of estrone at the ERα and ERβ was 2.6% and 4.3% of that of estradiol, respectively. (wikipedia.org)
  • 2002) stated that in vitro callus culture of immature wheat embryos is strongly stimulated by androsterone but regeneration is similar to control estrone and progesterone inhibits the first leaf and a callus growth of immature embryos in in vitro culture. (thefreedictionary.com)
  • progestin
  • Estrogen and progestin therapy (EPT) has been associated with increases in MD. Dense breast tissue is characterized by increased stromal tissue and (to a lesser degree) increased numbers of breast epithelial cells. (biomedcentral.com)
  • Hormone therapy, estrogen plus progestin (E+P) particularly, is associated with increased risk of breast cancer. (aacrjournals.org)
  • giving a progestin with an estrogen mitigates the risk. (wikipedia.org)
  • namely
  • Today, it is recognized that CCE can be generated by at least three distinct microsomal, P450-mediated enzymatic activities, namely 2-, 4-, and 2/4-hydroxylases, which produce both 2- and 4-OH derivatives of either E 2 or E 1 . (aacrjournals.org)
  • cancer
  • In this study we investigated the effect of TNF-α on the estrogen metabolic pathway in MCF-7, a breast cancer cell line. (jcancer.org)
  • It is well established that prolonged exposure to estrogens especially estradiol, is an important risk factor for genesis and promotion of breast cancer [ 2 , 3 ]. (jcancer.org)
  • However, there is conceivable evidence that estrogen induced breast cancer can also occur by a non ER-alpha mediated mechanism involving the estrogen metabolic pathway [ 5 ]. (jcancer.org)
  • Over the past 30 years a large number of case-control and cohort studies have been conducted that examined circulating levels of estrogens and/or their urinary excretion to detect any differences in estrogen concentrations that may contribute to cancer. (biomedcentral.com)
  • Estrogens are important in breast cancer development. (biomedcentral.com)
  • These enzymes are all known to be genetically variant in the human population, and additional studies to assess the role CYP1A2, CYP2C19 , and CYP3A5 in breast cancer risk are indicated. (aacrjournals.org)
  • The endogenous estrogens (E) estradiol (E 2 ) and estrone (E 1 ) contribute to breast cancer risk through their role as growth promoters ( 1 - 4 ). (aacrjournals.org)
  • Many studies have shown an association between the urinary ratio of 2-OH-estrone to 16α-OH-estrone and breast cancer risk, but other studies have not found such an association ( 24 - 27 ). (aacrjournals.org)
  • It is widely recognized that estrogens play a primary role in development and growth of human breast cancer. (aacrjournals.org)
  • endometrium
  • In the female, estradiol acts as a growth hormone for tissue of the reproductive organs, supporting the lining of the vagina, the cervical glands, the endometrium, and the lining of the fallopian tubes. (wikipedia.org)
  • In the luteal phase, estradiol, in conjunction with progesterone, prepares the endometrium for implantation. (wikipedia.org)
  • In these studies, prior to administration of estrone, amenorrhea, atrophy of the breasts (as well as flaccidity and small and non-erectile nipples), vagina, and endometrium, vaginal dryness, and subjective symptoms of ovariectomy (e.g., hot flashes, mood changes) were all present in the women. (wikipedia.org)
  • Treatment with estrone was found to dose- and time-dependently produce a variety of effects, including breast changes, reproductive tract changes of the vagina, cervix, and endometrium/uterus, and relief from the subjective symptoms of ovariectomy, as well as increased libido. (wikipedia.org)