Estrogen mimic

Other classes of commonly used compounds are also under suspicion as hormone mimics. These include alkylphenols and their reaction products with ethylene oxide, which are used as detergents, as well as phthalates, which are used as plasticizers.59 These detergents might be replaced with alkyl polyglycosides that can be made from renewable sugars and fats (see Chap. 12). Di-/ -butyl 

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Coumestans, such as coumestrol, are found in high concentrations in alfalfa and clover and have been recognized, along with formononetin, as the cause of infertility in grazing herbivores. Whereas coumestrol acts as an estrogen mimic directly, formononetin has to be metabolized to the estrogenically active compounds diadzein, equol, or >-demethylangolensein. 

A developing area of research has been endocrine disruption. Apparently, a wide variety of materials can interfere with or mimic endocrine function. Estrogen mimics and the possible modes of action of these materials are discussed with particular emphasis on dioxins and the polychlorinated biphenyls (PCBs). Other classes of compounds and modes of action are also summarized in this section. 

The pesticide DDT is an estrogen mimic that affects the body by elevating hormone levels. This, however, is not its only effect. DDE, the metabolite of DDT, is a fat soluble species that persists for long periods of time in the human body that has the opposite effect of DDT. DDE depletes hormones by accelerating their breakdown and elimination. This leaves the body with a short supply of not just estrogen, but testosterone and other steroid hormones as wellJ18 ... 

A number of structurally different xenobiotic chemicals are estrogen mimics. These compounds include pesticides, industrial chemicals, and components of many plastics, including polystyrene and polycarbonate. Some are listed in Table 22.2. 

Fig. 1. Estrogen and estrogen mimics. Many natural plant compounds (e.g. coumestrol) and synthetic chemicals (e.g. ethynylestradiol, diethylstilbestrol, 4-nonylphenol, o,p DDT, and kepone) act as endocrine disruptors by mimicking or blocking normal estrogen function via estrogen receptor dependent or independent mechanisms.

Tollefsen, K.E., R. Mathisen and J. Stenersen. Estrogen mimics bind with similar affinity and specificity to the hepatic estrogen receptor in Atlantic Salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). Gen. Comp. Endocrinol. 126 14-22, 2002. 

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