Endocrine Abstracts

The results concerning the role of leptin in mediating effect of food restriction on ovarian functions, in controlling these functions, as well as the endocrine and intracellular mechanisms of leptin action are reviewed.In our experiments, food restriction resulted in a reduction in rabbit and chicken plasma leptin, GH, IGF1 and gonadal steroid hormone levels and ovulation rate. Malnutrition (serum deprivation) inhibited hormone release and the expressio...

We are the first who studied the control and the role of transcription factors in the regulation of reproductive functions. Our presentation represents a short review of original data concerning external (temperature, calories restriction) and internal (hormones, protein kinases, RNA interference) in control of selected transcription factors (p53, NFkB, STAT1, CREB1), as well as their role in control of basic ovarian cell functions (proliferation, apoptosis, secretory activity...

Progress in reproductive medicine, assisted reproduction, veterinary medicine and animal production and biotechnology is promoted by discovery and application of the new extra- and intracellular regulators of reproductive functions. This is the review of original data concerning the role of some metabolic hormones (GH, leptin, ghrelin and obestatin), growth factors (IGF1, IGFBPs, EGF and thrombopoietin), intracellular mediators of their action (cyclic nucleotides, protein kina...

The recent original data concerning interrelationships between ghrelin and feeding, action of ghrelin on ovarian functions (proliferation, apoptosis, secretory activity, response to gonadotropins, oocyte maturation) and intracellular mechanisms of its action in different species (rabbit, pig, human, chicken) are reviewed. It was shown, that ghrelin can control proliferation, apoptosis, suppress release of ovarian hormones and inhibit response of ovarian cells to gonadotropin, ...

In our in-vitro experiments we examined the involvement of insulin-like growth factor type II (IGF-II) in the control of ovarian function in domestic fowl, together with the intracellular mechanisms of IGF-II action. Fragments of ovarian follicles were cultured with and without IGF-II (1-100 ng/ml), blockers of protein kinase A (PAK, KT5820, 10 mg/ml), tyrosine kinase (TK, AG1024, 1mg/ml), mitogen-activated protein konase (MAPK, PD98059, 10 mg/ml), cyclin-dependent protein kin...

Quercetin and resveratrol, powerful antioxidants and blockers of intracellular mTOR signalling system, are widely distributed in edible plants. Their action on ovarian cell functions and the interrelationships with gonadotropin are studied insufficiently. We examined the effect of FSH, quercetin, resveratrol and their combinations on proliferation and apoptosis of cultured porcine ovarian granulosa cells. Accumulation of marker of proliferation (PCNA) and marker of apoptosis (...

The aim of por in-vitro studies was to examine the involvement of transcription factor NF-kB (p50/p50, p65/p65) and FSH in control of porcine ovarian granulosa cells functions and the possible role of dimers p50/p50, p65/p65 in mediating FSH actions on these cells. Monolayer of primary granulosa cells was transfected with plasmids encoding human p50 cDNA and p65 cDNA, and cultured with or without addition of FSH (0, 1, 10 or 100 ng/ml). The accumulation of proteins p50 and p65...

The aim of our study was to examine the role of mTOR-dependent intracellular signalling pathway in tle control of ovarian functions. For this purpose we have examine the effect of two mTOR inhibitors (resveratrol and rapamycin) on the release of hormones by cultured rabbit ovarian fragments. The secretion of hormones (progesterone, testosterone, estradiol and prolactin) by fragments of rabbit ovaries cultured during 48 h with and without addition of resveratrol or rapamycine (...

The aim of the present study was to examine the role of steroid hormones in control of growth and obesity. We have measured plasma level of progesterone (P4), testosteron (T) and estradiol (E2) in 301 adolescent girls at different stages of their ovarian cycle, and compared they with standard morphometric indexes of their growth and obesity – body height, body mass, abdomen and hip circumstances and waist to hip ratio (WHR). The ovarian cycle-depende...

This study examined the action of GH on secretory activity and apoptosis (A) in porcine ovarian granulosa cells, as well as the role of protein kinase A (PKA), mitogen-activated protein kinase (MAPK), tyrosine kinase (TK), protein kinase G (PKG) and cyclin-dependent cdc2/p34 kinase in the mediation of its actions. The effects of exogenous pGH, with or without blockers of PKA (KT5720, Rp-cAMPS), MAPK (PD98059), TK (genistein, lavendustin), PKG (Rp-Br-PET-cGMPS, KT5823) and cdc2...