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Effects of oophorectomy and dehydroepiandrosterone (DHEA) on the cardiac mass in rats

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Karina Santos Teixeira
Total Authors: 1
Document type: Master's Dissertation
Press: São Paulo.
Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
Defense date:
Examining board members:
Carla Roberta de Oliveira Carvalho; Eliana Hiromi Akamine; Marco Antonio de Carvalho Filho
Advisor: Carla Roberta de Oliveira Carvalho

The reduction of gonadal hormones by menopause, the natural process of failure in the human follicle, or by surgical removal, is associated with increased incidence of cardiovascular disease in postmenopause women. The aim of this study is to evaluate the effect of oophorectomy and the DHEA supplementation on the morphology of cardiomyocytes, on the expression of proteins involved in cell growth, on apoptosis (IGF-1R, IR, IRS-1, PI3K, AKT, MAPKp42/44, JAK2) and on the cardiac function. Oophorectomy enhances both the body mass e heart weight, however the left ventricle showed a reduction in cardiomyocyte thickness by 15% and in the number of nuclei by 20%. Moreover the immunoblotting showed a decrease from 25 to 50% in the expression of IR, IRS-1 and AKT proteins in the hearts of oophorectomized rats. The hemodynamic parameters were similar between groups. Treatment with DHEA reversed the reduction in the number of nuclei with no change in the other parameters evaluated. Our data allow us to conclude that the absence of gonadal steroids per se induces morphological changes in the cardiomyocytes that may be related to apoptosis with no change on the heart pump function. The DHEA supplementation is able to reverse the reduced number of nuclei. (AU)

FAPESP's process: 09/11984-6 - Effects of sexual hormones reduction due to oophorectomy and dehydroepiandrosterone (DHEA) on cardiac hypertrophy induced by the isoproterenol in young adult female rats.
Grantee:Karina Santos Teixeira
Support Opportunities: Scholarships in Brazil - Master