The hippocampal system plays an important role in memory function. Neurohormones like androgens and estrogens that syntheses in hippocampus have an important role in learning and memory. Many biological effects of estrogens in the brain via estrogenic receptors (ERs) are investigated. The current research has conducted to assess the effect of estrogenic receptors on spatial discrimination in ra...

Estrogens, whether natural or synthetic, clearly influence reproductive development, senescence, and carcinogenesis. Pyrethroid insecticides are now the most widely used agents for indoor pest control, providing potential for human exposure. Using the MCF-7 human breast carcinoma cell line, we studied the estrogenic potential of several synthetic pyrethroid compounds in vitro using pS2 mRNA lev...

Estrogen's a Natural in Herbal Remedies Patricia Eagon, an associate professor of medicine at Pennsylvania's University of Pittsburgh, decided to consult an herbalist after she began to suspect that Premarin, the prescription estrogen she was taking for menopausal symptoms, was causing a rash on her leg. The herbalist, whom she had consulted before on other health matters, gave her a mixture of...

Chemical risk assessment procedures assign a major role to standardized toxicity tests, in which the response of a particular organism to a single test substance is determined under otherwise constant and favorable conditions in the laboratory. This approach fails to consider the potential for chemical interactions, as well as failing to consider how the toxicological response varies, depending...

Sewage, a complex mixture of organic and inorganic chemicals, is considered to be a major source of environmental pollution. A random screen of 20 organic man-made chemicals present in liquid effluents revealed that half appeared able to interact with the estradiol receptor. This was demonstrated by their ability to inhibit binding of 17 beta-estradiol to the fish estrogen receptor. Further stu...

conclusions these results show that zen and α-zol enhance the rate of cell division in er positive cells and therefore, exposure to this mycotoxin may increase the risk of breast cancer. results the results obtained from the present study demonstrated that both zen and α-zol enhance the cell viability of mcf-7 especially at low doses (1 - 500 ng/ml) and at a high dose of 125µg/ml after 24 and 4...

The methanolic extract of Flemingia macrophylla roots exhibited significant estrogenic activity in the transgenic plant assay system which was comparable to the activity of soybean extract. Utilizing estrogenic activity-guided fractionation, one new compound, fleminigin, together with 23 known compounds were isolated from F. macrophylla roots' methanolic extract. The structure of the new compou...

We previously demonstrated that estrogenic activity of bisphenol A (BPA) in the yeast estrogen screening assay was increased severalfold after incubation with rat liver S9 fraction in the presence of a NADPH-generating system. In this study, we investigated whether eight BPA-related compounds are similarly activated metabolically by rat liver S9 fraction. Three of the analogs exhibited an incre...

Most breast tumors show estrogen-dependent growth and are thus susceptible to antiestrogenic therapy. MCF-7 cells, obtained from a human estrogen-dependent breast carcinoma, are widely used for studying the modulation of estrogenic responses by different effectors. All-/r<ms-retinoic acid (RA) and 1,25-dihydroxyvitamin I), (Vit I),i inhibited estrogeninduced growth of MCF-7 cells and their effe...

Xenoestrogens are either natural or synthetic compounds that mimic the effects of endogenous estrogen. These compounds, such as bisphenol-A (BPA), and phthalates, are commonly found in plastic wares. Exposure to these compounds poses major risk to human health because of the potential to cause endocrine disruption. There is huge demand for a wide range of chemicals to be assessed for such poten...