Evaluation of the exposure for 28 days to isoflavones in senescent rats: behavioral and neurochemical aspects

• Grant number: 16/09433-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2016
• End date: June 30, 2017
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Helenice de Souza Spinosa
• Grantee: Daniele Sillis Cardoso Bella
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Isoflavones (ISOs) are natural phytoestrogens found in plants, mainly in soy products. ISOs can act as agonist of estrogen receptors, promoting estrogenic effects, or as an antagonist, blocking or altering these receptors and thus preventing estrogenic activity. Currently, ISOs are considered natural selective estrogen receptor modulators, being used mainly in ovarian failure (menopause), where there is a drastic reduction in the production of endogenous estrogen. The literature points out several studies, in vivo, especially with ovariectomized rats, aiming to mimic menopause, that showed the benefits of hormone replacement therapy with ISOs, including the improvement of cognitive responses. Thus, the aim of the present study is to show these effects, in senescent rats, once surgical menopause is different when compared to the natural physiological menopause. Furthermore, the use of senescent rats are an excellent model to assess cognitive responses, since these animals have spontaneous cognitive deficits that is characteristic of the aging process. This study aims to evaluate the behavioral and neurochemical effects of exposure for 28 days with ISOs in rats who are starting the senescence process (12 months old). Therefore, rats with 12 months of age, will receive for 28 days, 100 and 200 mg / kg of a commercial preparation containing ISOs, being assessed: body weight every three days; water consumption and food weekly; behavior in the open field, elevated plus maze, Barnes maze and forced swimming; and levels of neurotransmitters and metabolites in the cerebral cortex, hippocampus and striatum. (AU)