Effects of the addition of insulin-transferrin-selenium (ITS) and/or metformin to the maturation of porcine oocytes on cytoplasmic maturation and embryo development.

Context: One of the main problems of porcine in vitro maturation (IVM) is incomplete cytoplasmatic maturation. Nuclear and cytoplasmic maturation will determine the future success of fertilisation and embryo development. Insulin-transferrin-selenium (ITS) has insulin-like and antioxidant effects, and metformin (M) is an insulin-sensitiser and antioxidant drug.

Obesity modifies the implantation window and disrupts intrauterine embryo positioning in rats.

Obesity is a chronic disease that impairs female reproduction. When gestation is achieved, maternal obesity can cause offspring's health complications. We intended to evaluate the effects of maternal pre-conceptional obesity on uterine contractile activity, embryo implantation and offspring development.

Effects of gonadotrophins and insulin on glucose uptake in the porcine cumulus-oocyte complex during IVM.

The combination of gonadotrophins (LH and FSH) and insulin is frequently used in porcine oocyte IVM, but the individual effects of gonadotrophins and insulin have not been completely studied. The aim of this study was to investigate the mechanisms involved in glucose metabolism in the swine cumulus-oocyte complex (COC), analysing the effects of gonadotrophins (10IUmL-1 LH+10IUmL-1 FSH) and 0.4μUmL-1 insulin, during 44h of IVM, on glucose transport and consumption, as well as on nuclear maturation and sperm penetration.

Obesity alters the uterine environment before pregnancy.

Obesity is a metabolic disorder that predisposes to numerous diseases and has become a major global public health concern. Cafeteria diet (CAF) is the animal model used for the study of obesity that more closely reflects Western diet habits. Previously, we described that CAF administration for 60 days induces obesity in female rats and their fetuses develop macrosomia.

Metformin decreases the incidence of ovarian hyperstimulation syndrome: an experimental study.

Background: In assisted reproduction cycles, gonadotropins are administered to obtain a greater number of oocytes. A majority of patients do not have an adverse response; however, approximately 3-6% develop ovarian hyperstimulation syndrome (OHSS). Metformin reduces the risk of OHSS but little is known about the possible effects and mechanisms of action involved.

Link between metformin and the peroxisome proliferator-activated receptor γ pathway in the uterine tissue of hyperandrogenized prepubertal mice.

Chronic hyperandrogenism alters the peroxisome proliferator-activated receptor γ (PPARγ) pathway in the uterine tissue of prepubertal mice. The gene and protein expression of PPARγ is not modified, but the gene and protein expression of 12-lipoxygenase (12-LOX), an enzyme that synthesizes PPARγ ligands, is decreased. The antihyperglycemic drug metformin can prevent this adverse effect.

Peroxisome proliferator-activated receptor gamma and early folliculogenesis during an acute hyperandrogenism condition.

Acute hyperandrogenism decreases serum P levels and induces early apoptosis of antral follicles by a mechanism mediated by the peroxisome proliferator-activated receptor gamma system and independent of the steroidogenic acute regulator protein.

The effects of metformin on uterine tissue of hyperandrogenized BALB/c mice.

The present study investigated the role of the N, N'-dimethylbiguanide metformin (50 mg/kg body weight in 0.05 ml water, given orally with a canulla) in preventing the adverse effects generated by hyperandrogenism on uterine function. Daily injection of dehydroepiandrosterone (DHEA: 6 mg/100 g body weight in 0.

Detrimental effects of hyperandrogenism on uterine functions.

The aim of the present work was to study some of the adverse effects produced by hyperandrogenism on the uterine function. Daily injection of dehydroepiandrosterone (DHEA: 6 mg/ 100 g body weight, sc) for 20 consecutive days induced polycystic ovaries in BALB/c mice. In this model, we found that DHEA produced alterations on uterine histology closely related to the development of tumour structures.

Role of the N, N'-dimethylbiguanide metformin in the treatment of female prepuberal BALB/c mice hyperandrogenized with dehydroepiandrosterone.

The present study investigated the role of the N, N{'}-dimethylbiguanide metformin (50 mg/100 g body weight in 0.05 ml water, given orally with a canulla) in the prevention of endocrine and immune disorders provoked by the hyperandrogenization with dehydroepiandrosterone (DHEA) in prepuberal BALB/c mice. The treatment with DHEA (6 mg/100 g body weight in 0.

The influence of dehydroepiandrosterone on early pregnancy in mice.

The aim of the present report was to study the role of high levels of dehydroepiandrosterone (DHEA) on the ovarian function and embryonic resorption during early pregnancy in BALB/c mice. Pregnant animals were injected with DHEA following both the post-implantatory (DHEA-2) and peri-implantatory (DHEA-6) models. Morphological studies of implantation sites showed 40% of embryonic resorption in the DHEA-2 group while 100% of resorption was observed in the DHEA-6 group.