title: Multi-centre assessment of nitroblue tetrazolium reactivity in human semen as a potential marker of oxidative stress.
abstract: The nitroblue tetrazolium (NBT) reaction as a tracer of oxidative stress was examined in 707 ejaculates from seven clinics. Semen was initially surveyed by classifying the NBT reaction using a pre-established rank for the Oxisperm® test based on three colourimetric levels: L1, low (n = 141 [20%]); L2, medium (n = 538 [76%]) and L3, high (n = 28 [4%]). L3 was indicative of a high level of superoxide anions. Halosperm® chromatin dispersion assay was used to analyse samples of ejaculates 30 min after ejaculation; no difference was found in DNA fragmentation of L1 or L3; L3 category semen samples incubated for 24 h at 37oC showed a significantly faster rate (P < 0.001) of DNA damage than those in L1. The NBT reaction was further characterized in the ejaculates of 100 patients to determine the relative contribution of seminal plasma, spermatozoa, or both. Seminal plasma was the most significant fraction of •O2-localization, whereas sperm fractions generated detectable reactive oxygen species in only 32% of the ejaculates. Formazan precipitates were primarily associated with the sperm mid-piece and seminal leukocytes; however, not all spermatozoa stained positive to formazan and not all leukocytes presented with equivalent production of superoxide anions.
authors.affiliation: Department of Biology, Universidad Autónoma de Madrid, Madrid, 28049, Spain.
authors.forename: Jaime
authors.initials: J
authors.lastname: Gosálvez
authors.affiliation: Tecnomed, Centro Medico Biologico, Nardò, Lecce, Italy.
authors.forename: Lamberto
authors.initials: L
authors.lastname: Coppola
authors.affiliation: Genetics Unit, INIBIC-Complejo Hospitalario Universitario A Coruña (CHUAC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Fernández
authors.affiliation: Department of Biology, Universidad Autónoma de Madrid, Madrid, 28049, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: López-Fernández
authors.affiliation: Centro de Fertilidad, Tuxpan 6. Col. Roma Sur. Mexico DF, Mexico.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Góngora
authors.affiliation: Invimed Fertility Clinics, Embryology Laboratories, Center of Biomedical Research, WULS, 36 Rakowiecka Street, 02-532 Warsaw, Poland.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Faundez
authors.affiliation: SJ Science Inc., 972-8, Shin Jung 4 Dong, Yang Chun Gu, Seoul, Republic of Korea.
authors.forename: John
authors.initials: J
authors.lastname: Kim
authors.affiliation: Arzt, Frauenarzt (Gynäkologe), Weiterbildungen: Reproduktionsmedizin, Ambulante Operationen, Brühlstr. 19, 30169 Hannover, Germany.
authors.forename: Nabil
authors.initials: N
authors.lastname: Sayme
authors.affiliation: Ginefiv, Calle José Silva, 18, 28043 Madrid, Spain.
authors.forename: Moises
authors.initials: M
authors.lastname: de la Casa
authors.affiliation: Genetics Unit, INIBIC-Complejo Hospitalario Universitario A Coruña (CHUAC), As Xubias, 84, 15006 A Coruña, Spain.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Santiso
authors.affiliation: Queensland Fertility Group, 55 Little Edward Street, Spring Hill 4000, Australia.
authors.forename: Keith
authors.initials: K
authors.lastname: Harrison
authors.affiliation: American Center for Reproductive Medicine, Cleveland Clinic Foundation, 10681 Carnegie Avenue, Cleveland, OH 44195, USA.
authors.forename: Ashok
authors.initials: A
authors.lastname: Agarwal
authors.affiliation: School of Agriculture and Food Sciences, The University of Queensland, Gatton 4343, Australia. Electronic address: s.johnston1@uq.edu.au.
authors.forename: Stephen
authors.initials: S
authors.lastname: Johnston
authors.affiliation: ANDROFERT, Andrology and Human Reproduction Clinic, Av. Dr. Heitor Penteado, 1464, Campinas, SP 13075-460, Brazil.
authors.forename: Sandro C
authors.initials: SC
authors.lastname: Esteves
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D006801:Humans; D008297:Male; D009580:Nitroblue Tetrazolium / Q000378:metabolism*; D018384:Oxidative Stress; D012661:Semen / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism
chemical_list: D015415:Biomarkers; D013481:Superoxides; D009580:Nitroblue Tetrazolium
keywords: Human spermatozoa; Nitroblue tetrazolium; Oxidative stress; Oxisperm®; •O(2)(−) generation