The effect of higher doses of LH during oocyte maturation in the lipid profile of murine oocytes

• Grant number: 13/11031-4
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2013
• End date: August 31, 2015
• Field of knowledge: Biological Sciences - Biology
• Principal Investigator: Renato Fraietta
• Grantee: Talitha Dinardo Oleinki
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

In assisted reproduction techniques of high complexity, patients undergo a medical stimulation of the ovaries in order to obtain a higher number of viable oocysts for treatment. There are some stimulus protocols using FSH (follicle stimulating hormone) associated with the LH (luteinizing hormone) can mimetize the physiological effect. The number of mature oocytes obtained with the stimulus is mainly affected by maternal age and ovarian response to gonadotropins used. Although only the FSH is required for the ovarian follicle growth, a minimal amount of LH is required to achieve the adequate follicle steroidogenesis, ovulation and corpus luteum formation (Balasch et al, 1995;. Couzinet et al., 1988). The role of LH in controlled ovarian hyperstimulation is still controversial. This study aims to evaluate the effect of higher doses LH during oocyte maturation in the lipid profile of the Mus musculus oocyte and quality of DNA from cumulus cells. Oocytes are matured by rFSH technique with recombinant LH (LH group). These oocytes are from mice C57 / black6 females who receive three different hormonal stimuli: (i) only PMSG; (ii) with PMSG and hCG microdose (iii) PMSG microdose recombinant LH. The oocytes are analyzed by mass spectrometry (MALDI-TOF) and cumulus cells by the alkaline comet technique for determine the degree of DNA fragmentation. With this result, it is expected to understand the processes by which the LH could influence possible changes in oocyte lipid composition and quality of cumulus cells. (AU)