The process of cumulus mucification in pig preovulatory follicles was examined by scanning electron microscopy. The localization of extracellular material and changes in the granulosa cell surface were observed at 0, 16, 20 and 40 h after hCG injection. At 0 h the pig oocyte cumulus complex was closely attached to the parietal layer of granulosa cells. Cumulus and parietal granulosa cells had m...

Acrylamide (ACR) is a chemical compound with severe neurotoxicity, genotoxicity, carcinogenicity and reproductive toxicity. Recent studies showed that ACR impairs the function of reproductive organs, e.g., epididymis and testes. In vitro maturation of mouse oocyte is a sensitive assay to identify potential chemical hazard to female fertility. The aim of this study was to evaluate the adverse ef...

Paracrine factors secreted by the oocyte regulate a broad range of cumulus cell functions. Characteristically, cumulus cells have a low incidence of apoptosis and we proposed that this is due to oocyte-secreted factors acting in an anti-apoptotic manner. Bovine cumulus-oocyte complexes (COC) were aspirated from abattoir-derived ovaries and oocytectomized (OOX) by microsurgical removal of the oo...

OBJECTIVE To test whether angiotensin II (AngII) could modulate apoptosis of human granulosa-lutein (GL) cells from gonadotropin-stimulated follicles. DESIGN In vitro assays on mural and cumulus granulosa cells. SETTING University laboratory and private IVF practice. PATIENT(S) One hundred six consecutive women undergoing 113 IVF cycles. INTERVENTION(S) Purified human GL mural or cumulu...

The present study was conducted to investigate the effects of ovarian morphology on oocyte quantity and quality, as well as the effect of preincubated granulosa cells (PGCs) on in vitro maturation of buffalo oocytes and steroid hormone production. A total of 52 ovarian pairs were grouped into 3 types: Type I (with functional corpus luteum), Type II (with regressed corpus luteum), or Type III (w...

A better understanding of the paracrine and autocrine regulatory loops within the cumulus-oocyte complex (COC) is fundamental for the improvement of in vitro maturation (IVM) outcomes in humans and domestic species. This review presents the most important local regulators identified in the COC to date with special attention to those secreted by the oocyte and acting on cumulus cells, as well as...

There is increasing evidence supporting the role of vitamin D in telomere biology and thus potential need for normal status to develop a competent oocyte. The unreliable results obtained with immunoassay-based methods have supported use liquid chromatography-tandem mass spectrometry (LC-MS/MS) other metabolites measurement. We previously reported that 24,25-dihydroxyvitamin D3 (24,25(OH)2D3), m...

BACKGROUND Supplementation of bovine oocyte-cumulus complexes during in vitro maturation (IVM) with 1 μM of docosahexaenoic acid (DHA), C22:6 n-3 polyunsaturated fatty acid, was reported to improve in vitro embryo development. The objective of this paper was to decipher the mechanisms of DHA action. RESULTS Transcriptomic analysis of 1 μM DHA-treated and control cumulus cells after 4 h IVM sh...

STUDY QUESTION Is the activity of sirtuin 3 (SIRT3) altered in granulosa and cumulus cells from young women with reduced ovarian reserve or women of advanced maternal age? SUMMARY ANSWER SIRT3 mRNA and active protein in granulosa and cumulus cells were decreased in women with reduced ovarian reserve and advanced maternal age. WHAT IS KNOWN ALREADY Young women with reduced ovarian reserve or...

OBJECTIVE By focussing on differences in the mural granulosa cell (MGC) and cumulus cell (CC) transcriptomes from follicles resulting in competent (live birth) and non-competent (no pregnancy) oocytes the study aims on defining a competence classifier expression profile in the two cellular compartments. DESIGN A case-control study. SETTING University based facilities for clinical services a...