Possible role or SIRT 1in human ovarian granulosa cells

"In mammals, Sirt1, a member of the sirtuin family, functions as a nicotinamide adenine dinucleotide-dependent protein deacetylase, and has important physiological roles, including the stress response. The involvement of SIRT1 in the stress response is attributed to interaction with transcription factors belonging to the FOXO family, which play a key role in cellular processes such as cell cycle arrest, differentiation, detoxification of ROS, DNA repair and apoptosis . Despite the fact that SIRT1 knockout mice have impaired gametogenesis and embryogenesis, reduced informations are present in the literature on the role of sirtuins in the female gonad. In this work, we investigated the expression of SIRT1 and FOXO3A, the transcription factor that plays an important role for the survival of ovarian follicles, in human granulosa cells. For this purpose have been used samples from women aged between 28 and 42 years subjected to PMA with a primary indication of male infertility. The stimulation was performed on all patients with long protocol and administration of analogo rFSH and rLH and oocyte maturation was induced by rHCG. Granulosa cells, isolated by follicular fluid, were lysed and subjected to Western blotting. We were highlighted the presence of bands with molecular weight of about 110 kDa and 70 kDa, in all samples analyzed, using the antiSIRT1 and antiFOXO3A antibody respectively. This result is the first evidence of the expression of these proteins in human granulosa cells of periovulatory follicles. This represents an important starting point for defining the cellular pathway involved in the response to stress condition associated in ovarian aging and dysfunction."