title: Inducible nitric oxide synthase and heme oxygenase 1 are expressed in human cumulus cells and may be used as biomarkers of oocyte competence.
abstract: The interplay between oocyte and surrounding cumulus cells (CCs) during follicular growth influences oocyte competence to undergo fertilization and sustain embryo development. The expression of many genes and proteins in CCs has been suggested as potential biomarker of oocyte competence in human in vitro fertilization (IVF). In the present study, we analyzed 90 human cumulus-oocyte complexes obtained during IVF procedure: 30 CCs were analyzed using quantitative real-time polymerase chain reaction and 60 CCs using Western blotting analysis to detect gene and protein expression of some enzymes related to oxidative stress, that is, the 3 nitric oxide synthase (NOS) isoforms and heme oxygenase 1 (HO-1). In the group of 60 CCs, we also investigated the expression and phosphorylation of IkBα, a known inhibitor of the nuclear factor κB (NF-κB) pathway, which controls several redox-sensitive genes. The expression of the messenger RNAs (mRNAs) was related to the oocyte morphological analysis performed by polarized light microscopy and to the occurrence of normal fertilization after intracytoplasmic sperm injection. We observed that the amount of iNOS and HO-1 mRNAs and proteins is significantly higher, and that in the meanwhile the NF-κB pathway is activated, in CCs corresponding to oocytes that were not fertilized in comparison to CCs whose corresponding oocyte showed normal fertilization. Instead, no correlation between the fertilization and the oocytes' morphological data was observed. These results suggest that the increase in iNOS and HO-1 mRNAs expression in CCs is a negative index of oocyte fertilizability and might be an useful tool for oocyte selection.
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy Department of Public Health and Pediatrics, University of Torino, Torino, Italy loredana.bergandi@unito.it.
authors.forename: Loredana
authors.initials: L
authors.lastname: Bergandi
authors.affiliation: Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy.
authors.forename: Gemma
authors.initials: G
authors.lastname: Basso
authors.affiliation: Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Evangelista
authors.affiliation: Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Canosa
authors.affiliation: Department of Public Health and Pediatrics, University of Torino, Torino, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Dalmasso
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Aldieri
authors.affiliation: Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Revelli
authors.affiliation: Department of Surgical Sciences, University of Torino, S. Anna Hospital, Torino, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Benedetto
authors.affiliation: Department of Oncology, University of Torino, Torino, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Ghigo
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002478:Cells, Cultured; D054885:Cumulus Cells / Q000201:enzymology*; D005260:Female; D005298:Fertility; D005307:Fertilization in Vitro; D015971:Gene Expression Regulation, Enzymologic; D051547:Heme Oxygenase-1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D000072000:NF-KappaB Inhibitor alpha; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism*; D009865:Oocytes / Q000502:physiology*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation
chemical_list: D020672:I-kappa B Proteins; C000606204:NFKBIA protein, human; D012333:RNA, Messenger; D000072000:NF-KappaB Inhibitor alpha; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; C496541:HMOX1 protein, human; D051547:Heme Oxygenase-1
keywords: heme oxygenase 1; human cumulus cells; human in vitro fertilization; nitric oxide synthase (iNOS, eNOS, and nNOS) isoforms