Evaluation of estrogenic, antiestrogenic and genotoxic activity of nemorosone, the major compound found in brown Cuban propolis

Background: Brown propolis is the major type of propolis found in Cuba; its principal component is nemorosone, the major constituent of Clusia rosea floral resins. Nemorosone has received increasing attention due to its strong in vitro anti-cancer action. The citotoxicity of nemorosone in several human cancer cell lines has been reported and correlated to the direct action it has on the estrogen receptor (ER). Breast cancer can be treated with agents that target estrogen-mediated signaling, such as antiestrogens. Phytoestrogen can mimic or modulate the actions of endogenous estrogens and the treatment of breast cancer with phytoestrogens may be a valid strategy, since they have shown anti-cancer activity.Methods: The aim of the present investigation was to assess the capacity of nemorosone to interact with ERs, by Recombinant Yeast Assay (RYA) and E-screen assays, and to determine by comet assay, if the compound causes DNA-damaging in tumoral and non-tumoral breast cells.Results: Nemorosone did not present estrogenic activity, however, it inhibited the 17-β-estradiol (E2) action when either of both methods was used, showing their antiestrogenicity. The DNA damage induced by the benzophenone in cancer and normal breast cells presented negative results.Conclusion: These findings suggest that nemorosone may have therapeutic application in the treatment of breast cancer. © 2013 Camargo et al.; licensee BioMed Central Ltd.

Involvement of pituitary gonadotropins, gonadal steroids and breeding season in sex change of protogynous dusky grouper, Epinephelus marginatus (Teleostei: Serranidae), induced by a non-steroidal aromatase inhibitor

Two experiments were performed using the aromatase inhibitor (AI) letrozole (100mg/kg) to promote sex change, from female-to-male, in protogynous dusky grouper. One experiment was performed during the breeding season (spring) and the other at the end of the breeding season (summer). During the spring, AI promoted sex change after 9weeks and the sperm produced was able to fertilize grouper oocytes. During the summer, the sex change was incomplete; intersex individuals were present and sperm was not released by any of the animals. Sex changed gonads had a lamellar architecture; cysts of spermatocytes and spermatozoa in the lumen of the germinal compartment. In the spring, after 4weeks, 11ketotestosterone (11KT) levels were higher in the AI than in control fish, and after 9weeks, coincident with semen release, testosterone levels increased in the AI group, while 11KT returned to the initial levels. Estradiol (E2) levels remained unchanged during the experimental period. Instead of decreasing throughout the period, as in control group, 17 α-OH progesterone levels did not change in the AI-treated fish, resulting in higher values after 9weeks when compared with control fish. fshβ and lhβ gene expression in the AI animals were lower compared with control fish after 9weeks. The use of AI was effective to obtain functional males during the breeding season. The increase in androgens, modulated by gonadotropins, triggered the sex change, enabling the development of male germ cells, whereas a decrease in E2 levels was not required to change sex in dusky grouper. © 2013 Elsevier Inc.

Perfil metabólico de cálcio e ósseo de pacientes soropositivos para HIV em uso ou não da terapia antirretroviral

Pós-graduação em Alimentos e Nutrição - FCFAR

Efeito da metformina em mulheres obesas com a síndrome de hiperandrogenismo-resistência insulínica-acantose nigricans

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Variação do ciclo estral de novilhas Bos taurus indicus (Nelore) em diferentes estações do ano

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Medicina Veterinária - FCAV

Inseminação artificial intrauterina por videolaparoscopia em veado catingueiro (Mazama gouazoubira) com sêmen congelado

Pós-graduação em Medicina Veterinária - FCAV

Restabelecimento da atividade ovariana em vacas nelore (Bos taurus indicus) tratadas com implante subcutâneo de agonista de GnRH (deslorelina) durante 70 dias

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação dos distúrbios metabólicos de pacientes obesas, grau III, antes e depois da cirurgia bariátrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência do uso de drogas ilícitas na análise seminal e hormonal

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos da bupropiona sobre o comportamento sexual, parâmetros espermáticos e fertilidade de ratos machos e sobre a contratilidade do ducto epididimático in vitro

Pós-graduação em Biologia Geral e Aplicada - IBB

Desenvolvimento reprodutivo de ratos machos expostos ao agente hipolipemiante rosuvastatina

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)