Oestrogens effects

Tyler, C.R. and Routledge, E.J. (1998). Oestrogenic effects in fish in English rivers with evidence of their causation. Pure and Applied Chemistry 70, 1795-1804. 

PRINCE R L and DICK I (1997) Oestrogen effects on calcium membrane transport a new view of the inter-relationship between oestrogen deficiency and age-related osteoporosis. Osteoporosis Int 7, S150-S154. 

Alkylphenol ethoxylates (APEOs) are a class of surfactants that have been used widely in the drilling fluid industry. The popularity of these surfactants is based on their cost-effectiveness, availability, and range of obtainable hydrophilic-lipophilic balance values [693]. Studies have shown that APEOs exhibit oestrogenic effects and can cause sterility in some male aquatic species. This may have subsequent human consequences, and such problems have led to a banning of their use in some countries and agreements to phase out their use. Alternatives to products containing APEOs are available, and in some cases they show an even better technical performance. 

ZEA resembles the human 17P-oestradiol hormone produced by theovaries. Although almost non-toxic, in very small doses it has oestrogenic effects that can disrupt the human endocrine system (Benbrook, 2005). It is important to note that transformation products of ZEA can have three to four times higher endocrine disrupting activity than ZEA. 

Messinis IE, Templeton A (1990) Anti-oestrogen effect of clomiphene citrate in oestrogen-treated, hypogonadal women. Hum Reprod 5 150-152... 

Progestogens inhibit GnRH secretion and suppress LH release. They have anti-oestrogenic effects by reducing the number of oestrogen receptors and increasing oestradiol dehydrogenase. 

Vague, J., J. C. Garrigues, J. Berthet, and G. Favier. The oestrogenic effect of several plant oils. Ann Endocrinol 1959 18 745-751. 

In the case of some oestrogenic chemicals (that mimic the effects of the female hormone oestrogen) it has been shown that what should be added to predict the combined effect of a mixture is not the effects of the individual chemicals but their concentrations (Silva et al, 2002). This means that a substance present at a concentration at which on its own it has no oestrogenic effect will contribute to the total oestrogenic effect of a mixture containing other oestrogenic chemicals. For such substances there is in practice no real threshold concentration below which they do not have an effect. Such no-effect levels are a crucial part of chemicals risk assessment, as I will explain in Chapter 7. 

The piperazinyl derivative showed the greatest in vitro activity, with a mean IC5o value of 1.64 pM over all cell lines, that is, tenfold lower than cisplatin. It was particularly active against the hormone-dependent breast, cervix and ovarian cells, implicating an oestrogenic/anti-oestrogenic effect. This compound also activates caspase-3 in ovarian cells, suggesting that the mechanism of cell death is apoptosis rather than necrosis. 

The effect observed on ER+ breast cancer cells is again the result of the oestrogenic effect expected for these compounds, which all show an affinity for... 

ERa, minus the cytotoxic component observed on the ER-negative cancer cells. At a concentration of 1 pM, only the most cytotoxic complexes 4 and 5 are able to overpower the oestrogenic effect of these compounds. Complexes 7 and 8, which are the least cytotoxic on the MDA-MB-231 cells, show a clear proliferative effect. Compound 9 strikes a perfect balance between oestrogenic and cytotoxic effects and shows no overall effect on the MCF-7 cells at 1 pM. 

Aniseed contains volatile oil, furanocou-marins, flavonoids, fatty acids, phenylpro-panoids, sterols and proteins. Anethole has an observed oestrogenic effect, and the seeds as a whole are mildly oestrogenic. This effect may substantiate the herb s use as a stimulant of breast-milk production (http //www.herbs2000.com/herbs/herbs anise.htm). 

The volatile oil in aniseed provides the basis for its internal use to ease griping, intestinal colic and flatulence. It also has a marked expectorant and antispasmodic action and may be used in bronchitis and in tracheitis, where there is persistent irritable coughing, and to reduce the symptoms of whooping cough. Externally, the oil may be used in an ointment base for the treatment of scabies and lice infestations. Aniseed s mild oestrogenic effects, thought... 

Adverse oestrogen effects can include abdominal cramps, nausea, vomiting, headache, dizziness, depression, mood changes, hypertension, headache and fluid retention. Some major problems can occur with oestrogen therapy, including thromboembolism, seizures and risk of stroke. There is some evidence of a small increased incidence of breast, ovarian and endometrial cancer, which is related to the duration of HRT use. 

OPIOIDS OESTROGENS Effect of morphine may be 1 by combined oral contraceptives Hepatic metabolism of morphine ist Be aware that morphine dose may need to be t. Consider using an alternative opioid such as pethidine... 

Both aniseed and star-anise are used as spices and for distillation of anise oil. Besides the main ingredient anethole, it contains a polymeric product, dianethole, with oestrogenic effects. Aniseed has been reputed to increase milk secretion, promote menstruation, facilitate childbirth and increase libido. Aniseed is reported to be expectorant, carminative and exert sympathomimetic-type effects. These effects are attributed to anethole. The expectorant effect of aniseed oil is experimentally verified by measuring the amount of secretion from an upper respiratory tract and measuring its viscosity. In therapeutic doses, anethole is reported to cause minimal hepatotoxicity. 

Our present meagre understanding of normal endocrine processes in invertebrates makes the assessment of chemical endocrine disruption in the field difficult (LeBlanc 1999). Steroid roles differ between species and sometimes sexes, and their influence may vary at different developmental stages. In most studies of invertebrates, endocrine disruption appears to involve androgenization rather than oestrogenic effects (see Box 7.2). Arthropods (crustaceans and insects), annelids and molluscs use ecdysteroids, terpenoids and vertebratelike sex steroids for endocrine control. For example, the ecdysteroid ecdysone is naturally converted to 20-hydroxyecdysone (Fig. 7.10), which induces moulting (ecdysis) in both insect larvae and crustaceans. 

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