Letrozole: an emerging array of hope for infertile women

Ovulation induction has been a major breakthrough in the management of female infertility since many decades. Letrozole, an aromatase inhibitor has been used as a potential therapy for ovulation induction. A large number of clinical evidences have been emerging which cite the beneficial role of Letrozole in conditions like anovulatory infertility, polycystic ovary syndrome (PCOS), unexplained infertility and an incipient role in endometriosis- related infertility with regards to higher live-birth rates. Letrozole is a superior alternative to Clomiphene citrate (CC) which has been used conventionally as ovulation inducer. Clomiphene citrate has certain well-defined disadvantages, whereas Letrozole overcomes these limitations to a reasonable extent. The peripheral anti-estrogenic effect of CC leads to prolonged depletion of estrogens receptors, adversely affecting endometrial growth and development as well as quantity and quality of cervical mucus. Persistent blockade of estrogen receptor leads to CC resistance and is associated with reduced ovulation and pregnancy rates. Available evidences suggest Letrozole is superior to CC owing to the lack of persistent anti-estrogenic action due to its short half- life and lack of action on estrogen receptors. This typically leads to monofollicular growth and also higher live birth rates. The current evidences suggest that Letrozole can be placed as first line therapy for the management of infertility due to PCOS and unexplained infertility.

Mudanças comportamentais e fisiológicas determinadas pelo ciclo biológico feminino ­ climatério à menopausa / Behavioral and physiological changes determined by the female biological cycle ­ climacteric to menopause

A menopausa, período da falência ovariana, aparece como um marco corporal desencadeando sinais e sintomas que necessitam de controle e avaliação para garantir qualidade de vida no processo do envelhecimento feminino. O objetivo deste trabalho foi investigar as ações do estrogênio no período que caracteriza o climatério/menopausa, a partir de uma revisão integrativa, cujos descritores foram: ações do estrogênio, sinais/sintomas do climatério/menopausa e terapia de reposição hormonal. O estrogênio apresenta receptores em todos os órgãos e, portanto, atua nas características anatômicas, fisiológicas e emocionais; estimula o crescimento da massa óssea e muscular; atua como antioxidante; exerce ação cardioprotetora e neuroprotetora; contribui na vitalidade emocional e sexual. Com isso, percebe-se que no climatério ocorre uma redução drástica nos níveis de estrogênio, que culmina com a ausência estrogênica na menopausa e esse fato acarreta desequilíbrio de diferentes sistemas, até atingir uma nova adaptação.(AU)

Menopause appears as a body landmark in the aging process, where along with ovarian failure, it can trigger signs and symptoms that require control and evaluation to ensure a good quality of life. The objective of this work was to investigate how the estrogen actions in the period that characterize the climacteric / menopause. From an integrative review, the descriptors were: estrogenic effects, signs and symptoms of climacteric and menopause and hormone replacement therapy. Estrogen has receptors in all organs and, therefore, acts on anatomical, physiological and emotional characteristics; in determining bone and muscle mass growth; action as antioxidant; as cardioprotective and neuroprotective; contribution to emotional and sexual vitality. It was verified that in the climacteric occurs a reduction of the hormonal levels that culminates with the menopause and that the estrogen absence causes in disequilibrium of different systems, until reaching a new adaptation.(AU)

Effects of acacetin on T47D cell proliferation / 中国药理学通报

Aim To investigate the effect of acacetin on cell proliferation and the influence of acacetin on estrogen receptor expression in vitro.Methods The proliferation rates and the cell cycle changes of acace-tin-treated T47D cells were measured by sulforhodam-ine B(SRB)assay and flow cytometry,respectively. Moreover,the mRNA expressions of estrogen receptor-alpha(ERα),estrogen receptor-beta(ERβ)and pro-liferating antigen(Ki67)were determined by quantita-tive real time PCR (qPCR).Western blot was em-ployed to detect the ERαand ERβprotein expression. Results Acacetin significantly promoted the prolifera-tion and increased the amount of cells arrested in S and G2 /M phase under the concentration of 0.001 ~1 0μmol·L -1 .Ki67 mRNA level and the ERαprotein level in T47D cells were remarkably upregulated after acacetin treatment.To clarify which estrogen receptors played a role in acacetin induced the proliferation of T47D cells,the combination treatment of acacetin and ERαinhibitor (MPP)/ERβ inhibitor (PHTPP) was employed.We found that MPP could reverse the cell proliferation,the cell arrested in S and G2 /M phase and the increased Ki67 mRNA level induced by acace-tin.PHTPP also alleviated the T47D cell proliferation induced by acacetin,whereas no significant changes were found in cell cycle and Ki67 mRNA level.Con-clusion Acacetin stimulates the cell proliferation of T47D cells in the concentration from 0.001 μmol · L -1 to 1 0 μmol·L -1 ,which is mainly mediated by ERα.

A Review of Environmental Estrogenic Effects of Alkylphenols / 环境与健康杂志

Alkylphenols(APs) , the second most widely used commercial non-ionic surfactants in the world, are the main degradated productions of alkylphenol ethoxylates (APEs). The structure, biodegradation, transportation and distribution in environment, environmental monitoring and management are reviewed in this paper. Many meaurement methods of APs show that APs possess estrogenoid effects, that mainly disturb endocrinal and reproductive system, especially, estrogen-dependent organs. APs are associated with decreased fertility, reproductive disfunction, inferbility and cancer formation. APs are able to bind estrogen receptors, to imitate or antagonize estrogen effects, to disturb formation and metabolism of endogenous hormones and receptors. APs are also able to change the structure, quantity and function of cells and to disturb the kinetics of cellcycle at cytological and molecular levels. The more work on epidemiological study and mechanism of APs are needed. Management program for controlling environmental pollution caused by APs is being speedily investigated and put into practice progressively. It is necessary to restrict the use of APEs.