What can we do with xenoestrogens?
1997887#0
Xenoestrogens are a type of xenohormone that imitates estrogen. They can be either synthetic or natural chemical compounds. Synthetic xenoestrogens include some widely used industrial compounds, such as PCBs, BPA, and phthalates, which have estrogenic effects on a living organism even though they differ chemically from the estrogenic substances produced internally by the endocrine system of any organism. Natural xenoestrogens include phytoestrogens which are plant-derived xenoestrogens. Because the primary route of exposure to these compounds is by consumption of phytoestrogenic plants, they are sometimes called "dietary estrogens". Mycoestrogens, estrogenic substances from fungi, are another type of xenoestrogen that are also considered mycotoxins.
Xenoestrogen
1997887#1
Xenoestrogens are clinically significant because they can mimic the effects of endogenous estrogen and thus have been implicated in precocious puberty and other disorders of the reproductive system.
Xenoestrogen
1997887#13
Another potential effect of xenoestrogens is on oncogenes, specifically in relation to breast cancer. Some scientists doubt that xenoestrogens have any significant biological effect, in the concentrations found in the environment. However, there is substantial evidence in a variety of recent studies to indicate that xenoestrogens can increase breast cancer growth in tissue culture.
Xenoestrogen
1997887#8
There is a concern that xenoestrogens may act as false messengers and disrupt the process of reproduction. Xenoestrogens, like all estrogens, can increase growth of the endometrium, so treatments for endometriosis include avoidance of products which contain them. Likewise, they are avoided in order to prevent the onset or aggravation of adenomyosis. Studies have implicated observations of disturbances in wildlife with estrogenic exposure. For example, discharge from human settlement including runoff and water flowing out of wastewater treatment plants release a large amount of xenoestrogens into streams, which lead to immense alterations in aquatic life. With a bioaccumulation factor of 10 –10, fish are extremely susceptible to pollutants. Streams in more arid conditions are thought to have more effects due to higher concentrations of the chemicals arising from lack of dilution. Xenoestrogen is not good for the health of the uterus. It reduces the flexibility of the uterine walls. Xenoestrogen makes the uterine walls thinner and fragile.
Xenoestrogen
1997887#17
The ubiquitous presence of such estrogenic substances is a significant health concern, both individually and for a population. Life relies on the transmission of biochemical information to the next generation, and the presence of xenoestrogens may interfere with this transgenerational information process through "chemical confusion" (Vidaeff and Sever), who state: "The results do not support with certainty the view that environmental estrogens contribute to an increase in male reproductive disorders, neither do they provide sufficient grounds to reject such a hypothesis."
Xenoestrogen
1997887#3
The potential ecological and human health impact of xenoestrogens is of growing concern. The word xenoestrogen is derived from the Greek words ξένο (xeno, meaning foreign), οἶστρος (estrus, meaning sexual desire) and γόνο (gene, meaning "to generate") and literally means "foreign estrogen". Xenoestrogens are also called "environmental hormones" or "EDC" (Endocrine Disrupting Compounds). Most scientists that study xenoestrogens, including The Endocrine Society, regard them as serious environmental hazards that have hormone disruptive effects on both wildlife and humans.
Xenoestrogen
41120978#2
Estrogen can be divided into four classes: 1) Animal Estrogens that includes estrone (E1), estradiol (E2), and estriol (E3); 2) Plant Estrogens (Phytoestrogens); 3) Fungi Estrogens (Mycoestrogens) and 4) Synthetic Estrogens (xenoestrogens). Xenoestrogens contain a large number of compounds that are synthesized or naturally exist. These estrogens imitate estrogen structure and can be designed to satisfy the need of new drugs. They may have a significant impact on neurodegenerative disease treatment due to their ease of synthesis and targeted specificity.
Estrogen and neurodegenerative diseases
1997887#31
BPA (Bisphenol A) is the monomer used to manufacture polycarbonate plastic and epoxy resins used as a lining in most food and beverage cans. BPA global capacity is in excess of per year and thus is one of the highest-volume chemicals produced worldwide. The ester bonds in the BPA-based polycarbonates could be subject to hydrolysis and leaching of BPA. But in the case of epoxypolymers formed from bisphenol A, it is not possible to release bisphenol A by such a reaction. It is also noteworthy that, of the bisphenols, bisphenol A is a weak xenoestrogen. Other compounds, such as bisphenol Z, have been shown to have stronger estrogenic effects in rats.
Xenoestrogen
1997887#12
The induction of CYP1A has been established to be a good bioindicator for xenoestrogen exposure. In addition, xenoestrogens stimulate vitellogenin (Vtg), which acts as a nutrient reserve, and Zona readiata proteins (Zrp), which forms eggshells. Therefore, Vtg and Zrp are biomarkers to exposure for fish.
Xenoestrogen
1997887#29
Non-human animal studies have shown that exposure to environmental contaminants with estrogenic activity can accelerate the onset of puberty. A potential mechanism has been described in rats exposed to DDT or beta-estradiol in which GnRH pulsatile secretion was found to be increased. Oral exposure of female rats to xenoestrogens has been shown to cause pseudo precocious puberty (early vaginal opening and early first estrus). A study of dioxin in immature female rats induced early follicular development and phthalates are known to decrease the anogenital distance in newborn rats. Although this article focuses on the effects of xenoestrogens and reproductive function in females, numerous animal studies also implicate environmental estrogens' and androgens' adverse effects on the male reproduction system. Administration of estrogens to developing male animals reduces testicular weight and decreases sperm production. The small phallus size of male alligators has been linked to contamination of their natural Florida habitat with DDT. Data from animal research is abundant demonstrating the adverse effects on reproduction of hormonally active compounds found in the environment.
Xenoestrogen