It is well established that age-related decline of the biological capacity of a woman to reproduce is primarily related to the poor developmental potential of her gametes. This renders female ageing the most significant determinant of success in IVF. Starting with a reference picture of the main molecular and cellular failures of aged oocytes, granulosa cells and follicular microenvironment, this review focuses on age-related biochemical mechanisms underlying these changes. According to the most relevant concept of ageing, age-associated malfuction results from physiological accumulation of irreparable damage to biomolecules as an unavoidable side effect of normal metabolism. More than a decade after the free radical theory of ovarian ageing, biological and clinical research supporting the involvement of oxidative injuries in follicle ageing is discussed. Looking for the aetiology of oxidative stress, we consider the effect of ageing on ovarian and follicular vascularization. Then, we propose a potential role of advanced glycation end-products known to be involved in the physiological ageing of most tissues and organs. We conclude that future investigation of age-related molecular damage in the different ovarian components will be imperative in order to evaluate the possibility to save or rescue the developmental potential of aged oocytes.
The presence of anti-thyroid antibodies in ovarian follicles, as demonstrated for the first time in this study, may play a critical role in female infertility related to thyroid autoimmunity.
In spite of the optimisation of cryopreservation protocols, post-thawing trauma to mammalian gametes cannot be completely avoided. Based on recent literature, cellular cryodamage in reproductive cells has been extensively characterised in terms of changes in the cell structure, whereas biochemical alterations have been poorly investigated. The present paper reviews the current knowledge about the involvement of oxidative stress in frozen-thawed cells by considering the most relevant studies in sperm and oocytes. Recognising that spermatozoa are highly susceptible to oxidative damage induced by cryopreservation, the need for further research is highlighted in order to understand whether changes in the redox state have a role in the reduced developmental potential of cryopreserved human reproductive cells.
Patients with endometriosis are characterized by the ability of the endometrium to implant and by the peritoneal response to the tissue; angiogenic factors may play a significant role in the aetiology of endometriosis supporting the implantation of ectopic endometrial cells. Vascular endothelial growth factor (VEGF) is a mitogen, morphogen and chemoactractant for endothelial cells and, in vivo, it is a powerful mediator for vessel permeability. Interleukin-8 (IL-8) is a chemoatractant for neutrophils and is a potent angiogenic factor. Women (n = 20) with ovarian endometriomata and 10 women with follicular cysts were enrolled in this study to investigate the role of VEGF and IL-8 in the development and maintenance of ovarian endometriomata. Cystic fluids were collected by laparoscopy, immediately centrifuged and stored until the enzyme-linked immunosorbent assays were performed. The VEGF and IL-8 concentrations were found to be significantly higher in the fluids of the ovarian endometriomata than in those of the follicular cysts of controls (P < 0.001 and P < 0.001 respectively); in addition, a significant inverse correlation between the VEGF cystic fluid concentrations and the diameter of the endometriotic adnexal masses was found (r = -0.56, P = 0.01). The evidence that the high concentrations of VEGF and IL-8 are present in the ovarian endometriomata indicates that angiogenesis could be a specific event both for the progression and maintenance of such cysts.
Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, chronic anovulation, polycystic ovaries at ultrasound evaluation, and quite frequently by insulin resistance or compensatory hyperinsulinemia. Attention has been given to the role of inositol-phosphoglycan (IPG) mediators of insulin action and growing evidences suggest that a deficiency of D-chiro-inositol (DCI) containing IPG might be at the basis of insulin resistance, frequent in PCOS patients. On such basis, we investigated the efficacy on insulin sensitivity and hormonal parameters of 8 weeks treatment with myo-inositol (MYO) (Inofert, ItalPharmaco, Milano, Italy) at the dosage of 2 g day in a group (n = 42) of obese PCOS patients,. After the treatment interval body mass index (BMI) and insulin resistance decreased together with luteinizing hormone (LH), LH/FSH and insulin. When subdividing the patients according to their fasting insulin levels, Group A (n = 15) insulin below 12 µU/ml and Group B (n = 27) insulin above 12 µU/ml, MYO treatment induced similar changes in both groups but only patients of Group B showed the significant decrease of both fasting insulin plasma levels (from 20.3 ± 1.8 to 12.9 ± 1.8 µU/ml, p < 0.00001) and of area under the curve (AUC) of insulin under oral glucose tolerance test (OGTT). In conclusion, our study supports the hypothesis that MYO administration is more effective in obese patients with high fasting insulin plasma levels.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.